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1

The Independent Investigation Method.  

ERIC Educational Resources Information Center

The Independent Investigation Method is presented, a model developed to enable gifted students to grow in their independence as they move through a research assignment. The seven-step process guides elementary students from beginning to end in the research process, including topic, goal setting, research, organizing, goal evaluation, product, and…

Morse, Virginia; Nottage, Cindy

2001-01-01

2

Investigation of Near Shannon Limit Coding Schemes.  

National Technical Information Service (NTIS)

Turbo codes can deliver performance that is very close to the Shannon limit. This report investigates algorithms for convolutional turbo codes and block turbo codes. Both coding schemes can achieve performance near Shannon limit. The performance of the sc...

S. C. Kwatra J. Kim F. Mo

1999-01-01

3

Independent peer review of nuclear safety computer codes  

SciTech Connect

A structured process of independent computer code peer review has been developed to assist the US Nuclear Regulatory Commission (NRC) and the US Department of Energy in their nuclear safety missions. This paper focuses on the process that evolved during recent reviews of NRC codes.

Boyack, B.E.; Jenks, R.P.

1993-02-01

4

Independent peer review of nuclear safety computer codes  

SciTech Connect

A structured process of independent computer code peer review has been developed to assist the US Nuclear Regulatory Commission (NRC) and the US Department of Energy in their nuclear safety missions. This paper focuses on the process that evolved during recent reviews of NRC codes.

Boyack, B.E.; Jenks, R.P.

1993-01-01

5

Reward Sharpens Orientation Coding Independently of Attention  

PubMed Central

It has long been known that rewarding improves performance. However it is unclear whether this is due to high level modulations in the output modules of associated neural systems or due to low level mechanisms favoring more “generous” inputs? Some recent studies suggest that primary sensory areas, including V1 and A1, may form part of the circuitry of reward-based modulations, but there is no data indicating whether reward can be dissociated from attention or cross-trial forms of perceptual learning. Here we address this issue with a psychophysical dual task, to control attention, while perceptual performance on oriented targets associated with different levels of reward is assessed by measuring both orientation discrimination thresholds and behavioral tuning functions for tilt values near threshold. We found that reward, at any rate, improved performance. However, higher reward rates showed an improvement of orientation discrimination thresholds by about 50% across conditions and sharpened behavioral tuning functions. Data were unaffected by changing the attentional load and by dissociating the feature of the reward cue from the task-relevant feature. These results suggest that reward may act within the span of a single trial independently of attention by modulating the activity of early sensory stages through a improvement of the signal-to-noise ratio of task-relevant channels.

Baldassi, Stefano; Simoncini, Claudio

2011-01-01

6

Getting Students to be Successful, Independent Investigators  

NSDL National Science Digital Library

Middle school students often struggle when writing testable problems, planning valid and reliable procedures, and drawing meaningful evidence-based conclusions. To address this issue, the author created a student-centered lab handout to facilitate the inquiry process for students. This handout has reduced studentsâ frustration and helped them become more independent and successful investigators.

Thomas, Jeffery D.

2010-02-01

7

An Investigation of Different String Coding Methods.  

ERIC Educational Resources Information Center

Investigates techniques for automatic coding of English language strings which involve titles drawn from bibliographic files, but do not require prior knowledge of source. Coding methods (basic, maximum entropy principle), results of test using 6,260 titles from British National Bibliography, and variations in code element ordering are…

Goyal, Pankaj

1984-01-01

8

Color coding information: assessing alternative coding systems using independent brightness and hue dimensions.  

PubMed

Can independent dimensions of brightness and hue be used in a combined digital information code? This issue was addressed by developing 2 color-coding systems and testing them on informed and naive participants in signal beam detection and classification experiments for simulated sonar displays. Each coding system's results showed both groups efficiently used encoded information that varied simultaneously along the 2 dimensions of brightness and hue. Findings support the proposed procedures for developing color information codes and the validity of such information codes across different populations. Applied significance of these results is provided by the test of principled methods of color-code construction and the demonstration that extending the information content of user interfaces beyond 1 dimension is feasible in practice. PMID:11477979

Jameson, K A; Kaiwi, J L; Bamber, D

2001-06-01

9

Independent accident investigation: a modern safety tool.  

PubMed

Historically, safety has been subjected to a fragmented approach. In the past, every department has had its own responsibility towards safety, focusing either on working conditions, internal safety, external safety, rescue and emergency, public order or security. They each issued policy documents, which in their time were leading statements for elaboration and regulation. They also addressed safety issues with tools of various nature, often specifically developed within their domain. Due to a series of major accidents and disasters, the focus of attention is shifting from complying with quantitative risk standards towards intervention in primary operational processes, coping with systemic deficiencies and a more integrated assessment of safety in its societal context. In The Netherlands recognition of the importance of independent investigations has led to an expansion of this philosophy from the transport sector to other sectors. The philosophy now covers transport, industry, defense, natural disaster, environment and health and other major occurrences such as explosions, fires, and collapse of buildings or structures. In 2003 a multi-sector covering law will establish an independent safety board in The Netherlands. At a European level, mandatory investigation agencies are recognized as indispensable safety instruments for aviation, railways and the maritime sector, for which EU Directives are in place or being progressed [Transport accident and incident investigation in the European Union, European Transport Safety Council, ISBN 90-76024-10-3, Brussel, 2001]. Due to a series of major events, attention has been drawn to the consequences of disasters, highlighting the involvement of rescue and emergency services. They also have become subjected to investigative efforts, which in return, puts demands on investigation methodology. This paper comments on an evolutionary development in safety thinking and of safety boards, highlighting some consequences for strategic perspectives in a further development of independent accident investigation. PMID:15231346

Stoop, John A

2004-07-26

10

On Network Coding of Independent and Dependent Sources in Line Networks  

Microsoft Academic Search

We investigate the network coding capacity for line networks. For independent sources and a special class of dependent sources, we fully characterize the capacity region of line networks for all possible demand structures (e.g., multiple unicast, mixtures of unicasts and multicasts, etc.) Our achievability bound is derived by first decomposing a line network into single-demand components and then adding the

Mayank Bakshi; Michelle Effros; WeiHsin Gu; Ralf Koetter

2007-01-01

11

Independent coding of object motion and position revealed by distinct contingent aftereffects  

Microsoft Academic Search

Despite several findings of perceptual asynchronies between object features, it remains unclear whether independent neuronal populations necessarily code these perceptually unbound properties. To examine this, we investigated the binding between an object’s spatial frequency and its rotational motion using contingent motion aftereffects (MAE). Subjects adapted to an oscillating grating whose direction of rotation was paired with a high or low

Paul F. Bulakowski; Kami Koldewyn; David Whitney

2007-01-01

12

Independent population coding of speech with sub-millisecond precision.  

PubMed

To understand the strategies used by the brain to analyze complex environments, we must first characterize how the features of sensory stimuli are encoded in the spiking of neuronal populations. Characterizing a population code requires identifying the temporal precision of spiking and the extent to which spiking is correlated, both between cells and over time. In this study, we characterize the population code for speech in the gerbil inferior colliculus (IC), the hub of the auditory system where inputs from parallel brainstem pathways are integrated for transmission to the cortex. We find that IC spike trains can carry information about speech with sub-millisecond precision, and, consequently, that the temporal correlations imposed by refractoriness can play a significant role in shaping spike patterns. We also find that, in contrast to most other brain areas, the noise correlations between IC cells are extremely weak, indicating that spiking in the population is conditionally independent. These results demonstrate that the problem of understanding the population coding of speech can be reduced to the problem of understanding the stimulus-driven spiking of individual cells, suggesting that a comprehensive model of the subcortical processing of speech may be attainable in the near future. PMID:24305831

Garcia-Lazaro, Jose A; Belliveau, Lucile A C; Lesica, Nicholas A

2013-12-01

13

Independent source coding for control over noiseless channels  

Microsoft Academic Search

By focusing on a class of source coding schemes built around entropy coded dithered quantizers, we develop a framework to deal with average data-rate constraints in a tractable manner that combines ideas from both information and control theories. We focus on a situation where a noisy linear system has been designed assuming transparent feedback and, due to implementation constraints, a

Eduardo I. Silva; Milan S. Derpich; J. stergaard

2010-01-01

14

Two independent transcription initiation codes overlap on vertebrate core promoters.  

PubMed

A core promoter is a stretch of DNA surrounding the transcription start site (TSS) that integrates regulatory inputs and recruits general transcription factors to initiate transcription. The nature and causative relationship of the DNA sequence and chromatin signals that govern the selection of most TSSs by RNA polymerase II remain unresolved. Maternal to zygotic transition represents the most marked change of the transcriptome repertoire in the vertebrate life cycle. Early embryonic development in zebrafish is characterized by a series of transcriptionally silent cell cycles regulated by inherited maternal gene products: zygotic genome activation commences at the tenth cell cycle, marking the mid-blastula transition. This transition provides a unique opportunity to study the rules of TSS selection and the hierarchy of events linking transcription initiation with key chromatin modifications. We analysed TSS usage during zebrafish early embryonic development at high resolution using cap analysis of gene expression, and determined the positions of H3K4me3-marked promoter-associated nucleosomes. Here we show that the transition from the maternal to zygotic transcriptome is characterized by a switch between two fundamentally different modes of defining transcription initiation, which drive the dynamic change of TSS usage and promoter shape. A maternal-specific TSS selection, which requires an A/T-rich (W-box) motif, is replaced with a zygotic TSS selection grammar characterized by broader patterns of dinucleotide enrichments, precisely aligned with the first downstream (+1) nucleosome. The developmental dynamics of the H3K4me3-marked nucleosomes reveal their DNA-sequence-associated positioning at promoters before zygotic transcription and subsequent transcription-independent adjustment to the final position downstream of the zygotic TSS. The two TSS-defining grammars coexist, often physically overlapping, in core promoters of constitutively expressed genes to enable their expression in the two regulatory environments. The dissection of overlapping core promoter determinants represents a framework for future studies of promoter structure and function across different regulatory contexts. PMID:24531765

Haberle, Vanja; Li, Nan; Hadzhiev, Yavor; Plessy, Charles; Previti, Christopher; Nepal, Chirag; Gehrig, Jochen; Dong, Xianjun; Akalin, Altuna; Suzuki, Ana Maria; van IJcken, Wilfred F J; Armant, Olivier; Ferg, Marco; Strähle, Uwe; Carninci, Piero; Müller, Ferenc; Lenhard, Boris

2014-03-20

15

Independent verification and benchmark testing of the UNSAT-H computer code, Version 2.0  

SciTech Connect

Independent testing of the UNSAT-H computer code, Version 2.0, was conducted to establish confidence that the code is ready for general use in performance assessment applications. Verification and benchmark test problems were used to check the correctness of the FORTRAN coding, computational efficiency and accuracy of the numerical algorithm, and code, capability to simulate diverse hydrologic conditions. This testing was performed using a structured and quantitative evaluation protocol. The protocol consisted of: blind testing, independent applications, maintaining test equivalence and use of graduated test cases. Graphical comparisons and calculation of the relative root mean square (RRMS) values were used as indicators of accuracy and consistency levels. Four specific ranges of RRMS values were chosen for in judging the quality of the comparison. Four verification test problems were used to check the computational accuracy of UNSAT-H in solving the uncoupled fluid flow and heat transport equations. Five benchmark test problems, ranging in complexity, were used to check the code`s simulation capability. Some of the benchmark test cases include comparisons with laboratory and field data. The primary findings of this independent testing is that the UNSAT-H is fully operationaL In general, the test results showed that computer code produced unsaturated flow simulations with excellent stability, reasonable accuracy, and acceptable speed. This report describes the technical basis, approach, and results of the independent testing. A number of future refinements to the UNSAT-H code are recommended that would improve: computational speed and accuracy, code usability and code portability. Aspects of the code that warrant further testing are outlined.

Baca, R.G.; Magnuson, S.O.

1990-02-01

16

Independent verification and benchmark testing of the UNSAT-H computer code, Version 2. 0  

SciTech Connect

Independent testing of the UNSAT-H computer code, Version 2.0, was conducted to establish confidence that the code is ready for general use in performance assessment applications. Verification and benchmark test problems were used to check the correctness of the FORTRAN coding, computational efficiency and accuracy of the numerical algorithm, and code, capability to simulate diverse hydrologic conditions. This testing was performed using a structured and quantitative evaluation protocol. The protocol consisted of: blind testing, independent applications, maintaining test equivalence and use of graduated test cases. Graphical comparisons and calculation of the relative root mean square (RRMS) values were used as indicators of accuracy and consistency levels. Four specific ranges of RRMS values were chosen for in judging the quality of the comparison. Four verification test problems were used to check the computational accuracy of UNSAT-H in solving the uncoupled fluid flow and heat transport equations. Five benchmark test problems, ranging in complexity, were used to check the code's simulation capability. Some of the benchmark test cases include comparisons with laboratory and field data. The primary findings of this independent testing is that the UNSAT-H is fully operationaL In general, the test results showed that computer code produced unsaturated flow simulations with excellent stability, reasonable accuracy, and acceptable speed. This report describes the technical basis, approach, and results of the independent testing. A number of future refinements to the UNSAT-H code are recommended that would improve: computational speed and accuracy, code usability and code portability. Aspects of the code that warrant further testing are outlined.

Baca, R.G.; Magnuson, S.O.

1990-02-01

17

Pcigale: Porting Code Investigating Galaxy Emission to Python  

NASA Astrophysics Data System (ADS)

We present pcigale, the port to Python of CIGALE (Code Investigating Galaxy Emission) a Fortran spectral energy distribution (SED) fitting code developed at the Laboratoire d'Astrophysique de Marseille. After recalling the specifics of the SED fitting method, we show the gains in modularity and versatility offered by Python, as well as the drawbacks compared to the compiled code.

Roehlly, Y.; Burgarella, D.; Buat, V.; Boquien, M.; Ciesla, L.; Heinis, S.

2014-05-01

18

Independent coding of object motion and position revealed by distinct contingent aftereffects.  

PubMed

Despite several findings of perceptual asynchronies between object features, it remains unclear whether independent neuronal populations necessarily code these perceptually unbound properties. To examine this, we investigated the binding between an object's spatial frequency and its rotational motion using contingent motion aftereffects (MAE). Subjects adapted to an oscillating grating whose direction of rotation was paired with a high or low spatial frequency pattern. In separate adaptation conditions, we varied the moment when the spatial frequency change occurred relative to the direction reversal. After adapting to one stimulus, subjects made judgments of either the perceived MAE (rotational movement) or the position shift (instantaneous phase rotation) that accompanied the MAE. To null the spatial frequency-contingent MAE, motion reversals had to physically lag changes in spatial frequency during adaptation. To null the position shift that accompanied the MAE, however, no temporal lag between the attributes was required. This demonstrates that perceived motion and position can be perceptually misbound. Indeed, in certain conditions, subjects perceived the test pattern to drift in one direction while its position appeared shifted in the opposite direction. The dissociation between perceived motion and position of the same test pattern, following identical adaptation, demonstrates that distinguishable neural populations code for these object properties. PMID:17280696

Bulakowski, Paul F; Koldewyn, Kami; Whitney, David

2007-03-01

19

Category-dependent and category-independent goal-value codes in human ventromedial prefrontal cortex  

PubMed Central

To choose between manifestly distinct options, it is suggested that the brain assigns values to goals using a common currency. Although previous studies have reported activity in ventromedial prefrontal cortex (vmPFC) correlating with the value of different goal stimuli, it remains unclear whether such goal-value representations are independent of the associated stimulus categorization, as required by a common currency. Using multivoxel pattern analyses on functional magnetic resonance imaging (fMRI) data, we found a region of medial prefrontal cortex to contain a distributed goal-value code that is independent of stimulus category. More ventrally in the vmPFC, we found spatially distinct areas of the medial orbitofrontal cortex to contain unique category-dependent distributed value codes for food and consumer items. These results implicate the medial prefrontal cortex in the implementation of a common currency and suggest a ventral versus dorsal topographical organization of value signals in the vmPFC.

McNamee, Daniel; Rangel, Antonio; O'Doherty, John P

2013-01-01

20

Hundreds of conserved non-coding genomic regions are independently lost in mammals  

PubMed Central

Conserved non-protein-coding DNA elements (CNEs) often encode cis-regulatory elements and are rarely lost during evolution. However, CNE losses that do occur can be associated with phenotypic changes, exemplified by pelvic spine loss in sticklebacks. Using a computational strategy to detect complete loss of CNEs in mammalian genomes while strictly controlling for artifacts, we find >600 CNEs that are independently lost in at least two mammalian lineages, including a spinal cord enhancer near GDF11. We observed several genomic regions where multiple independent CNE loss events happened; the most extreme is the DIAPH2 locus. We show that CNE losses often involve deletions and that CNE loss frequencies are non-uniform. Similar to less pleiotropic enhancers, we find that independently lost CNEs are shorter, slightly less constrained and evolutionarily younger than CNEs without detected losses. This suggests that independently lost CNEs are less pleiotropic and that pleiotropic constraints contribute to non-uniform CNE loss frequencies. We also detected 35 CNEs that are independently lost in the human lineage and in other mammals. Our study uncovers an interesting aspect of the evolution of functional DNA in mammalian genomes. Experiments are necessary to test if these independently lost CNEs are associated with parallel phenotype changes in mammals.

Hiller, Michael; Schaar, Bruce T.; Bejerano, Gill

2012-01-01

21

Hundreds of conserved non-coding genomic regions are independently lost in mammals.  

PubMed

Conserved non-protein-coding DNA elements (CNEs) often encode cis-regulatory elements and are rarely lost during evolution. However, CNE losses that do occur can be associated with phenotypic changes, exemplified by pelvic spine loss in sticklebacks. Using a computational strategy to detect complete loss of CNEs in mammalian genomes while strictly controlling for artifacts, we find >600 CNEs that are independently lost in at least two mammalian lineages, including a spinal cord enhancer near GDF11. We observed several genomic regions where multiple independent CNE loss events happened; the most extreme is the DIAPH2 locus. We show that CNE losses often involve deletions and that CNE loss frequencies are non-uniform. Similar to less pleiotropic enhancers, we find that independently lost CNEs are shorter, slightly less constrained and evolutionarily younger than CNEs without detected losses. This suggests that independently lost CNEs are less pleiotropic and that pleiotropic constraints contribute to non-uniform CNE loss frequencies. We also detected 35 CNEs that are independently lost in the human lineage and in other mammals. Our study uncovers an interesting aspect of the evolution of functional DNA in mammalian genomes. Experiments are necessary to test if these independently lost CNEs are associated with parallel phenotype changes in mammals. PMID:23042682

Hiller, Michael; Schaar, Bruce T; Bejerano, Gill

2012-12-01

22

Proof-of-principle experiment of reference-frame-independent quantum key distribution with phase coding.  

PubMed

We have demonstrated a proof-of-principle experiment of reference-frame-independent phase coding quantum key distribution (RFI-QKD) over an 80-km optical fiber. After considering the finite-key bound, we still achieve a distance of 50?km. In this scenario, the phases of the basis states are related by a slowly time-varying transformation. Furthermore, we developed and realized a new decoy state method for RFI-QKD systems with weak coherent sources to counteract the photon-number-splitting attack. With the help of a reference-frame-independent protocol and a Michelson interferometer with Faraday rotator mirrors, our system is rendered immune to the slow phase changes of the interferometer and the polarization disturbances of the channel, making the procedure very robust. PMID:24402550

Liang, Wen-Ye; Wang, Shuang; Li, Hong-Wei; Yin, Zhen-Qiang; Chen, Wei; Yao, Yao; Huang, Jing-Zheng; Guo, Guang-Can; Han, Zheng-Fu

2014-01-01

23

A code to investigate complex metabolic models for dose calculation.  

PubMed

A code, DOSEDAY/DOSEYEAR, was developed as a research tool for calculating dose in humans from internally deposited radionuclides, using the International Commission on Radiation Protection (ICRP) Publication 30 compartmental scheme as a framework and ICRP Publication 30 values for default compartmental rate constants. This framework can be varied to investigate new rate constants, fractionation, recycling pathways, and other metabolic information. The compartmental model described in ICRP Publication 30 cannot easily be solved analytically; approximate solutions are generally used. The code calculates the numerical solution to a system of 70 simultaneous, stiff differential equations describing the compartmental model. Step sizes for numerical integration were determined internally by the code to insure stability, and a material balance was calculated for comparison with inputs, which provided a self-contained verification system. The code contains modules for calculating activity and decay in each compartment and for converting these values to dose. Using numerical integration techniques allowed researchers to use recycling compartments (i.e., as proposed for I) and to calculate dose over any time period. DOSEDAY/DOSEYEAR calculates dose for inhalation, ingestion, and injection intake pathways. Chronic intake may also be calculated, using a selected equational form to describe intake (i.e., sinusoidal, representing diurnal Rn exposure; linear, representing 1-d exposure to a constant source; etc.). The code is operational on any personal computer which supports compiled BASIC and thus provides researchers with a readily implemented problem-solving tool to investigate metabolic models. PMID:2606703

Clary, C L; Kirstein, B E

1989-01-01

24

Board Governance of Independent Schools: A Framework for Investigation  

ERIC Educational Resources Information Center

Purpose: This paper develops a theoretical framework to guide future inquiry into board governance of independent schools. Design/methodology/approach: The authors' approach is to integrate literatures related to corporate and educational boards, motivation, leadership and group processes that are appropriate for conceptualizing independent school…

McCormick, John; Barnett, Kerry; Alavi, Seyyed Babak; Newcombe, Geoffrey

2006-01-01

25

A Comparative Investigation on Model Selection in Independent Factor Analysis  

Microsoft Academic Search

With uncorrelated Gaussian factors extended to mutually independent factors beyond Gaussian, the conventional factor analysis is extended to what is recently called independent factor analysis. Typically, it is called binary factor analysis (BFA) when the factors are binary and called non-Gaussian factor analysis (NFA) when the factors are from real non-Gaussian distributions. A crucial issue in both BFA and NFA

Yujia An; Xuelei Hu; Lei Xu

2006-01-01

26

Evaluation of coding-independent functions of the transcribed bovine aromatase pseudogene CYP19P1  

PubMed Central

Background CYP19A1 encodes the aromatase which catalyzes the final reaction of estrogen biosynthesis. The bovine genome also contains a non-coding copy of CYP19A1, the transcribed pseudogene CYP19P1. Whereas CYP19A1 is transcribed in all estrogen-producing tissues, mainly in the placenta and gonads, the CYP19P1 transcript so far was detected in the placenta. Strikingly, one sequence segment of both transcripts exhibits an exceptional high identity of 98%, which implies selective pressure and suggests some kind of function. Only recently, indeed, coding-independent functions of several transcribed pseudogenes were reported. Therefore, we analyzed CYP19P1 and CYP19A1 transcripts with the aim to detect clues for gene–pseudogene interference. Findings The CYP19P1 transcript was first examined in silico for the presence of microRNA coding sequences and microRNA targets. Further, to identify tissues where CYP19P1 and CYP19A1 transcripts are co-expressed, as a pre-requisite for transcript interference, expression profiling was performed in a variety of bovine tissues. Our in silico analyses did neither reveal potential microRNA coding sequences, nor microRNA targets. Co-expression of the CYP19 loci was demonstrated in placental cotyledons and granulosa cells of dominant follicles. However, in granulosa cells of dominant follicles the concentration of CYP19P1 mRNA was very low compared to CYP19A1 mRNA. Conclusions CYP19P1 and CYP19A1 transcripts might interfere in placental cotyledons. However, in granulosa cells of dominant follicles relevant interference between gene and pseudogene transcripts is unlikely to occur because of the very low CYP19P1/CYP19A1 transcript ratio.

2014-01-01

27

C: a language for high-level, efficient, and machine-independent dynamic code generation  

Microsoft Academic Search

Dynamic code generation allows specialized code sequences to be created using runtime information. Since this information is by definitionnot available statically, the use of dynamic code generation can achieve performance inherently beyond that of static code generation. Previous attempts to support dynamic code generation have been low-level, expensive, or machine- dependent. Despite the growing use of dynamic code genera- tion,

Dawson R. Engler; Wilson C. Hsieh; M. Frans Kaashoek

1996-01-01

28

Independence.  

ERIC Educational Resources Information Center

Discusses the four planes of development and the periods of creation and crystallization within each plane. Identifies the type of independence that should be achieved by the end of the first two planes of development. Maintains that it is through individual work on the environment that one achieves independence. (KB)

Stephenson, Margaret E.

2000-01-01

29

The investigation of bandwidth efficient coding and modulation techniques  

NASA Technical Reports Server (NTRS)

The New Mexico State University Center for Space Telemetering and Telecommunications systems has been, and is currently, engaged in the investigation of trellis-coded modulation (TCM) communication systems. In particular, TCM utilizing M-ary phase shift keying is being studied. The study of carrier synchronization in a TCM environment, or in MPSK systems in general, has been one of the two main thrusts of this grant. This study has involved both theoretical modelling and software simulation of the carrier synchronization problem.

1992-01-01

30

RELAP5/MOD3 code manual: Summaries and reviews of independent code assessment reports. Volume 7, Revision 1  

SciTech Connect

Summaries of RELAP5/MOD3 code assessments, a listing of the assessment matrix, and a chronology of the various versions of the code are given. Results from these code assessments have been used to formulate a compilation of some of the strengths and weaknesses of the code. These results are documented in the report. Volume 7 was designed to be updated periodically and to include the results of the latest code assessments as they become available. Consequently, users of Volume 7 should ensure that they have the latest revision available.

Moore, R.L.; Sloan, S.M.; Schultz, R.R.; Wilson, G.E. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States)

1996-10-01

31

Investigation of dynamic models of independently rotating wheels of wagons  

Microsoft Academic Search

The article deals with the modelling of independently rotating wheels (IRW) systems for wagons. The research work of the intensity of rolling stock wheels rims and flanges is observed. The main performance objectives of IRW are to reduce winding of wheel?sets, to enable railway rolling stocks to achieve higher speeds, to decrease wear of rail and wheel rolling surface, to

Gintautas Bureika; Leonas Povilas Lingaitis; Šar?nas Mikali?nas

2004-01-01

32

A 2.9 ps equivalent resolution interpolating time counter based on multiple independent coding lines  

NASA Astrophysics Data System (ADS)

We present the design, operation and test results of a time counter that has an equivalent resolution of 2.9 ps, a measurement uncertainty at the level of 6 ps, and a measurement range of 10 s. The time counter has been implemented in a general-purpose reprogrammable device Spartan-6 (Xilinx). To obtain both high precision and wide measurement range the counting of periods of a reference clock is combined with a two-stage interpolation within a single period of the clock signal. The interpolation involves a four-phase clock in the first interpolation stage (FIS) and an equivalent coding line (ECL) in the second interpolation stage (SIS). The ECL is created as a compound of independent discrete time coding lines (TCL). The number of TCLs used to create the virtual ECL has an effect on its resolution. We tested ECLs made from up to 16 TCLs, but the idea may be extended to a larger number of lines. In the presented time counter the coarse resolution of the counting method equal to 2 ns (period of the 500 MHz reference clock) is firstly improved fourfold in the FIS and next even more than 400 times in the SIS. The proposed solution allows us to overcome the technological limitation in achievable resolution and improve the precision of conversion of integrated interpolators based on tapped delay lines.

Szplet, R.; Jachna, Z.; Kwiatkowski, P.; Rozyc, K.

2013-03-01

33

Do comments explain codes adequately?: investigation by text filtering  

Microsoft Academic Search

Comment lines in the software source code include descriptions of codes, usage of codes, copyrights, unused codes, comments, and so on. It is required for comments to explain the content of written code adequately, since the wrong description in the comment may causes further bug and confusion in maintenance. In this paper, we try to clarify a research question: \\

Yukinao Hirata; Osamu Mizuno

2011-01-01

34

Investigating language independence in HMM PoS\\/MSD-tagging  

Microsoft Academic Search

The paper presents an investigation of functional dependencies in morphosyntactic tagging using hidden Markov models. Starting from a well known fact that the HMM tagging paradigm relies on lexical knowledge acquired from training corpora and stored in form of transition and emission matrices, also called a language model, in the experiment, we apply the TnT trigram tagger on creating language

Z. Agic; M. Tadic; Z. Dovedan

2008-01-01

35

Investigation of Navier-Stokes Code Verification and Design Optimization  

NASA Technical Reports Server (NTRS)

With rapid progress made in employing computational techniques for various complex Navier-Stokes fluid flow problems, design optimization problems traditionally based on empirical formulations and experiments are now being addressed with the aid of computational fluid dynamics (CFD). To be able to carry out an effective CFD-based optimization study, it is essential that the uncertainty and appropriate confidence limits of the CFD solutions be quantified over the chosen design space. The present dissertation investigates the issues related to code verification, surrogate model-based optimization and sensitivity evaluation. For Navier-Stokes (NS) CFD code verification a least square extrapolation (LSE) method is assessed. This method projects numerically computed NS solutions from multiple, coarser base grids onto a freer grid and improves solution accuracy by minimizing the residual of the discretized NS equations over the projected grid. In this dissertation, the finite volume (FV) formulation is focused on. The interplay between the xi concepts and the outcome of LSE, and the effects of solution gradients and singularities, nonlinear physics, and coupling of flow variables on the effectiveness of LSE are investigated. A CFD-based design optimization of a single element liquid rocket injector is conducted with surrogate models developed using response surface methodology (RSM) based on CFD solutions. The computational model consists of the NS equations, finite rate chemistry, and the k-6 turbulence closure. With the aid of these surrogate models, sensitivity and trade-off analyses are carried out for the injector design whose geometry (hydrogen flow angle, hydrogen and oxygen flow areas and oxygen post tip thickness) is optimized to attain desirable goals in performance (combustion length) and life/survivability (the maximum temperatures on the oxidizer post tip and injector face and a combustion chamber wall temperature). A preliminary multi-objective optimization study is carried out using a geometric mean approach. Following this, sensitivity analyses with the aid of variance-based non-parametric approach and partial correlation coefficients are conducted using data available from surrogate models of the objectives and the multi-objective optima to identify the contribution of the design variables to the objective variability and to analyze the variability of the design variables and the objectives. In summary the present dissertation offers insight into an improved coarse to fine grid extrapolation technique for Navier-Stokes computations and also suggests tools for a designer to conduct design optimization study and related sensitivity analyses for a given design problem.

Vaidyanathan, Rajkumar

2004-01-01

36

Independent Investigation  

NSDL National Science Digital Library

This is an activity about constructing and conducting an experiment. Learners will choose a question of their individual design about light and the light spectrum, design an experiment to answer the question, present this design for peer review, make revisions, conduct the experiment, and present their findings. This activity is lesson 6 in a collection titled, In a Different Light.

37

The GUISurfer tool: towards a language independent approach to reverse engineering GUI code  

Microsoft Academic Search

Graphical user interfaces (GUIs) are critical components of today's software. Developers are dedicating a larger portion of code to implementing them. Given their increased importance, correctness of GUIs code is becoming essential. This paper describes the latest results in the development of GUISurfer, a tool to reverse engineer the GUI layer of interactive computing systems. The ultimate goal of the

João Carlos Silva; Carlos C. Silva; Rui D. Gonçalo; João Saraiva; José Creissac Campos

2010-01-01

38

Investigation of a panel code for airframe/propeller integration analyses  

NASA Technical Reports Server (NTRS)

The Hess panel code was investigated as a procedure to predict the aerodynamic loading associated with propeller slipstream interference on the airframe. The slipstream was modeled as a variable onset flow to the lifting and nonlifting bodies treated by the code. Four sets of experimental data were used for comparisons with the code. The results indicate that the Hess code, in its present form, will give valid solutions for nonuniform onset flows which vary in direction only. The code presently gives incorrect solutions for flows with variations in velocity. Modifications to the code to correct this are discussed.

Miley, S. J.

1982-01-01

39

Investigation of the Use of Erasures in a Concatenated Coding Scheme.  

National Technical Information Service (NTIS)

A new method for declaring erasures in a concatenated coding scheme is investigated. This method is used with the rate 1/2 K = 7 convolutional code and the (255, 223) Reed Solomon code. Errors and erasures Reed Solomon decoding is used. The erasure method...

S. C. Kwatra P. J. Marriott

1997-01-01

40

Empirical validation of the triple-code model of numerical processing for complex math operations using functional MRI and group Independent Component Analysis of the mental addition and subtraction of fractions  

Microsoft Academic Search

The suitability of a previously hypothesized triple-code model of numerical processing, involving analog magnitude, auditory verbal, and visual Arabic codes of representation, was investigated for the complex mathematical task of the mental addition and subtraction of fractions. Functional magnetic resonance imaging (fMRI) data from 15 normal adult subjects were processed using exploratory group Independent Component Analysis (ICA). Separate task-related components

Vincent J. Schmithorst; Rhonda Douglas Brown

2004-01-01

41

Memory for Pictures and Sounds: Independence of Auditory and Visual Codes  

Microsoft Academic Search

Three experiments examined the mnemonic independence of auditory and visual nonverbal stimuli in free recall. Stimulus lists consisted of (1) pictures, (2) the corresponding environmental sounds, or (3) picture-sound pairs. In Experiment 1, free recall was tested under three learning conditions: standard intentional, intentional with a rehearsal-inhibiting distracter task, or incidental with the distracter task. In all three groups, recall

VALERIE A. THOMPSON; ALLAN PAIVIO

1994-01-01

42

Modality-independent coding of spatial layout in the human brain.  

PubMed

In many nonhuman species, neural computations of navigational information such as position and orientation are not tied to a specific sensory modality [1, 2]. Rather, spatial signals are integrated from multiple input sources, likely leading to abstract representations of space. In contrast, the potential for abstract spatial representations in humans is not known, because most neuroscientific experiments on human navigation have focused exclusively on visual cues. Here, we tested the modality independence hypothesis with two functional magnetic resonance imaging (fMRI) experiments that characterized computations in regions implicated in processing spatial layout [3]. According to the hypothesis, such regions should be recruited for spatial computation of 3D geometric configuration, independent of a specific sensory modality. In support of this view, sighted participants showed strong activation of the parahippocampal place area (PPA) and the retrosplenial cortex (RSC) for visual and haptic exploration of information-matched scenes but not objects. Functional connectivity analyses suggested that these effects were not related to visual recoding, which was further supported by a similar preference for haptic scenes found with blind participants. Taken together, these findings establish the PPA/RSC network as critical in modality-independent spatial computations and provide important evidence for a theory of high-level abstract spatial information processing in the human brain. PMID:21620708

Wolbers, Thomas; Klatzky, Roberta L; Loomis, Jack M; Wutte, Magdalena G; Giudice, Nicholas A

2011-06-01

43

Modality-independent coding of spatial layout in the human brain  

PubMed Central

Summary In many non-human species, neural computations of navigational information such as position and orientation are not tied to a specific sensory modality [1, 2]. Rather, spatial signals are integrated from multiple input sources, likely leading to abstract representations of space. In contrast, the potential for abstract spatial representations in humans is not known, as most neuroscientific experiments on human navigation have focused exclusively on visual cues. Here, we tested the modality independence hypothesis with two fMRI experiments that characterized computations in regions implicated in processing spatial layout [3]. According to the hypothesis, such regions should be recruited for spatial computation of 3-D geometric configuration, independent of a specific sensory modality. In support of this view, sighted participants showed strong activation of the parahippocampal place area (PPA) and the retrosplenial cortex (RSC) for visual and haptic exploration of information-matched scenes but not objects. Functional connectivity analyses suggested that these effects were not related to visual recoding, which was further supported by a similar preference for haptic scenes found with blind participants. Taken together, these findings establish the PPA/RSC network as critical in modality-independent spatial computations and provide important evidence for a theory of high-level abstract spatial information processing in the human brain.

Wolbers, Thomas; Klatzky, Roberta L.; Loomis, Jack M.; Wutte, Magdalena G.; Giudice, Nicholas A.

2011-01-01

44

Investigation of Bandwidth-Efficient Coding and Modulation Techniques  

NASA Technical Reports Server (NTRS)

The necessary technology was studied to improve the bandwidth efficiency of the space-to-ground communications network using the current capabilities of that network as a baseline. The study was aimed at making space payloads, for example the Hubble Space Telescope, more capable without the need to completely redesign the link. Particular emphasis was placed on the following concepts: (1) what the requirements are which are necessary to convert an existing standard 4-ary phase shift keying communications link to one that can support, as a minimum, 8-ary phase shift keying with error corrections applied; and (2) to determine the feasibility of using the existing equipment configurations with additional signal processing equipment to realize the higher order modulation and coding schemes.

Osborne, William P.

1992-01-01

45

Geoelectric variations related to earthquakes observed during a 3-year independent investigation  

NASA Astrophysics Data System (ADS)

We present observations of the geoelectric field prior to some earthquakes. The data were collected during a three year (1992-1994) independent experimental investigation of VAN at the University of Patras Seismological Center. The recorded signals were: a) Gradual Variations of the Electric Field (GVEF), b) Periodic Variation of the Electric Field (PVEF), and c) Seismic Electric Signals (SES).

Tselentis, G.-Akis; Ifantis, Apostolos

46

Investigations with methanobacteria and with evolution of the genetic code  

NASA Technical Reports Server (NTRS)

Mycoplasma capricolum was found by Osawa et al. to use UGA as the code of tryptophan and to contain 75% A + T in its DNA. This change could have been from evolutionary pressure to replace C + G by A + T. Numerous studies have been reported of evolution of proteins as measured by amino acid replacements that are observed when homologus proteins, such as hemoglobins from various vertebrates, are compared. These replacements result from nucleotide substitutions in amino acid codons in the corresponding genes. Simultaneously, silent nucleotide substitutions take place that can be studied when sequences of the genes are compared. These silent evolutionary changes take place mostly in third positions of codons. Two types of nucleotide substitutions are recognized: pyrimidine-pyrimidine and purine-purine interchanges (transitions) and pyriidine-purine interchanges (transversions). Silent transitions are favored when a corresponding transversion would produce an amino acid replacement. Conversely, silent transversions are favored by probability when transitions and transversions will both be silent. Extensive examples of these situations have been found in protein genes, and it is evident that transversions in silent positions predominate in family boxes in most of the examples studied. In associated research a streptomycete from cow manure was found to produce an extracellular enzyme capable of lysing the pseudomurein-contining methanogen Methanobacterium formicicum.

Jukes, T. H.

1986-01-01

47

Investigation of cubic particles with uniaxial anisotropy using M^3 - a Matlab based micromagnetic code  

Microsoft Academic Search

We have developed a Matlab based micromagnetic code (M^3) to simulate three dimensional magnetic structures. We find that the mathematical notation and the multidimensional capabilities of Matlab greatly simplify code development and maintenance compared to other programming languages. Here we report on the investigation of the magnetic states of cubic particles with a reduced size L and a uniaxial anisotropy

Angelique Montgomery; Claudia Mewes; Tim Mewes

2010-01-01

48

An investigation of factors influencing public opinion of property bias in Canadian Criminal Code maximum sentences  

Microsoft Academic Search

TheCriminal Code of Canada (Code) provides many statutory maximum sentences (maxima) that are more severe for property offenses than for offenses, against people. Past research has shown that, at least in the abstract, people consider offenses against the person as more serious and deserving of more severe sentences than property offenses. The present research investigated whether these results would be

Kevin S. Douglas; James R. P. Ogloff

1996-01-01

49

Final report of the independent counsel for Iran/Contra matters. Volume 1: Investigations and prosecutions  

SciTech Connect

In October and November 1986, two secret U.S. Government operations were publicly exposed, potentially implicating Reagan Administration officials in illegal activities. These operations were the provision of assistance to the military activities of the Nicaraguan contra rebels during an October 1984 to October 1986 prohibition on such aid, and the sale of U.S. arms to Iran in contravention of stated U.S. policy and in possible violation of arms-export controls. In late November 1986, Reagan Administration officials announced that some of the proceeds from the sale of U.S. arms to Iran had been diverted to the contras. As a result of the exposure of these operations, Attorney General Edwin Meese III sought the appointment of an independent counsel to investigate and, if necessary, prosecute possible crimes arising from them. This is the final report of that investigation.

Walsh, L.E.

1993-08-04

50

User's manual for three dimensional FDTD version A code for scattering from frequency-independent dielectric materials  

NASA Technical Reports Server (NTRS)

The Finite Difference Time Domain Electromagnetic Scattering Code Version A is a three dimensional numerical electromagnetic scattering code based upon the Finite Difference Time Domain Technique (FDTD). This manual provides a description of the code and corresponding results for the default scattering problem. In addition to the description, the operation, resource requirements, version A code capabilities, a description of each subroutine, a brief discussion of the radar cross section computations, and a discussion of the scattering results.

Beggs, John H.; Luebbers, Raymond J.; Kunz, Karl S.

1991-01-01

51

INVESTIGATIONS OF NEUTRONICS OF SUBCRITICAL SYSTEMS WITH THE USE OF MCNP CODE  

Microsoft Academic Search

As the tool particularly appropriate for investigations of neutronics of subcritical systems, the MCNP code (4b version) has been chosen in view of its great advantages of universality and wide spread. Two simplified models of the systems have been assumed in calculations - a full-scale spherical assembly and a smaller cylindrical experimental one. The neutron multiplication process has been examined

S. TACZANOWSKI; M. KOPE

52

User's manual for two dimensional FDTD version TEA and TMA codes for scattering from frequency-independent dielectic materials  

NASA Astrophysics Data System (ADS)

The Penn State Finite Difference Time Domain Electromagnetic Scattering Code Versions TEA and TMA are two dimensional numerical electromagnetic scattering codes based upon the Finite Difference Time Domain Technique (FDTD) first proposed by Yee in 1966. The supplied version of the codes are two versions of our current two dimensional FDTD code set. This manual provides a description of the codes and corresponding results for the default scattering problem. The manual is organized into eleven sections: introduction, Version TEA and TMA code capabilities, a brief description of the default scattering geometry, a brief description of each subroutine, a description of the include files (TEACOM.FOR TMACOM.FOR), a section briefly discussing scattering width computations, a section discussing the scattering results, a sample problem set section, a new problem checklist, references and figure titles.

Beggs, John H.; Luebbers, Raymond J.; Kunz, Karl S.

1991-07-01

53

User's manual for two dimensional FDTD version TEA and TMA codes for scattering from frequency-independent dielectric materials  

NASA Astrophysics Data System (ADS)

The Penn State Finite Difference Time Domain Electromagnetic Scattering Code Versions TEA and TMA are two dimensional electromagnetic scattering codes based on the Finite Difference Time Domain Technique (FDTD) first proposed by Yee in 1966. The supplied version of the codes are two versions of our current FDTD code set. This manual provides a description of the codes and corresponding results for the default scattering problem. The manual is organized into eleven sections: introduction, Version TEA and TMA code capabilities, a brief description of the default scattering geometry, a brief description of each subroutine, a description of the include files (TEACOM.FOR TMACOM.FOR), a section briefly discussing scattering width computations, a section discussing the scattering results, a sample problem setup section, a new problem checklist, references, and figure titles.

Beggs, John H.; Luebbers, Raymond J.; Kunz, Karl S.

1991-11-01

54

User's manual for two dimensional FDTD version TEA and TMA codes for scattering from frequency-independent dielectric materials  

NASA Technical Reports Server (NTRS)

The Penn State Finite Difference Time Domain Electromagnetic Scattering Code Versions TEA and TMA are two dimensional electromagnetic scattering codes based on the Finite Difference Time Domain Technique (FDTD) first proposed by Yee in 1966. The supplied version of the codes are two versions of our current FDTD code set. This manual provides a description of the codes and corresponding results for the default scattering problem. The manual is organized into eleven sections: introduction, Version TEA and TMA code capabilities, a brief description of the default scattering geometry, a brief description of each subroutine, a description of the include files (TEACOM.FOR TMACOM.FOR), a section briefly discussing scattering width computations, a section discussing the scattering results, a sample problem setup section, a new problem checklist, references, and figure titles.

Beggs, John H.; Luebbers, Raymond J.; Kunz, Karl S.

1991-01-01

55

User's manual for two dimensional FDTD version TEA and TMA codes for scattering from frequency-independent dielectic materials  

NASA Technical Reports Server (NTRS)

The Penn State Finite Difference Time Domain Electromagnetic Scattering Code Versions TEA and TMA are two dimensional numerical electromagnetic scattering codes based upon the Finite Difference Time Domain Technique (FDTD) first proposed by Yee in 1966. The supplied version of the codes are two versions of our current two dimensional FDTD code set. This manual provides a description of the codes and corresponding results for the default scattering problem. The manual is organized into eleven sections: introduction, Version TEA and TMA code capabilities, a brief description of the default scattering geometry, a brief description of each subroutine, a description of the include files (TEACOM.FOR TMACOM.FOR), a section briefly discussing scattering width computations, a section discussing the scattering results, a sample problem set section, a new problem checklist, references and figure titles.

Beggs, John H.; Luebbers, Raymond J.; Kunz, Karl S.

1991-01-01

56

User's manual for three dimensional FDTD version C code for scattering from frequency-independent dielectric and magnetic materials  

NASA Technical Reports Server (NTRS)

The Penn State Finite Difference Time Domain Electromagnetic Scattering Code Version C is a three-dimensional numerical electromagnetic scattering code based on the Finite Difference Time Domain (FDTD) technique. The supplied version of the code is one version of our current three-dimensional FDTD code set. The manual given here provides a description of the code and corresponding results for several scattering problems. The manual is organized into 14 sections: introduction, description of the FDTD method, operation, resource requirements, Version C code capabilities, a brief description of the default scattering geometry, a brief description of each subroutine, a description of the include file (COMMONC.FOR), a section briefly discussing radar cross section computations, a section discussing some scattering results, a new problem checklist, references, and figure titles.

Beggs, John H.; Luebbers, Raymond J.; Kunz, Karl S.

1992-01-01

57

User's manual for three dimensional FDTD version C code for scattering from frequency-independent dielectric and magnetic materials  

NASA Technical Reports Server (NTRS)

The Penn State Finite Difference Time Domain Electromagnetic Scattering Code Version C is a three dimensional numerical electromagnetic scattering code based upon the Finite Difference Time Domain Technique (FDTD). The supplied version of the code is one version of our current three dimensional FDTD code set. This manual provides a description of the code and corresponding results for several scattering problems. The manual is organized into fourteen sections: introduction, description of the FDTD method, operation, resource requirements, Version C code capabilities, a brief description of the default scattering geometry, a brief description of each subroutine, a description of the include file (COMMONC.FOR), a section briefly discussing Radar Cross Section (RCS) computations, a section discussing some scattering results, a sample problem setup section, a new problem checklist, references and figure titles.

Beggs, John H.; Luebbers, Raymond J.; Kunz, Karl S.

1991-01-01

58

User's manual for three dimensional FDTD version A code for scattering from frequency-independent dielectric materials  

NASA Technical Reports Server (NTRS)

The Penn State Finite Difference Time Domain (FDTD) Electromagnetic Scattering Code Version A is a three dimensional numerical electromagnetic scattering code based on the Finite Difference Time Domain technique. The supplied version of the code is one version of our current three dimensional FDTD code set. The manual provides a description of the code and the corresponding results for the default scattering problem. The manual is organized into 14 sections: introduction, description of the FDTD method, operation, resource requirements, Version A code capabilities, a brief description of the default scattering geometry, a brief description of each subroutine, a description of the include file (COMMONA.FOR), a section briefly discussing radar cross section (RCS) computations, a section discussing the scattering results, a sample problem setup section, a new problem checklist, references, and figure titles.

Beggs, John H.; Luebbers, Raymond J.; Kunz, Karl S.

1992-01-01

59

Investigating the Magnetorotational Instability with Dedalus, and Open-Souce Hydrodynamics Code  

SciTech Connect

The magnetorotational instability is a fluid instability that causes the onset of turbulence in discs with poloidal magnetic fields. It is believed to be an important mechanism in the physics of accretion discs, namely in its ability to transport angular momentum outward. A similar instability arising in systems with a helical magnetic field may be easier to produce in laboratory experiments using liquid sodium, but the applicability of this phenomenon to astrophysical discs is unclear. To explore and compare the properties of these standard and helical magnetorotational instabilities (MRI and HRMI, respectively), magnetohydrodynamic (MHD) capabilities were added to Dedalus, an open-source hydrodynamics simulator. Dedalus is a Python-based pseudospectral code that uses external libraries and parallelization with the goal of achieving speeds competitive with codes implemented in lower-level languages. This paper will outline the MHD equations as implemented in Dedalus, the steps taken to improve the performance of the code, and the status of MRI investigations using Dedalus.

Burns, Keaton J; /UC, Berkeley, aff SLAC

2012-08-31

60

Investigation of Coded Source Neutron Imaging at the North Carolina State University PULSTAR Reactor  

SciTech Connect

A neutron imaging facility is located on beam-tube #5 of the 1-MWth PULSTAR reactor at the North Carolina State University. An investigation has been initiated to explore the application of coded imaging techniques at the facility. Coded imaging uses a mosaic of pinholes to encode an aperture, thus generating an encoded image of the object at the detector. To reconstruct the image recorded by the detector, corresponding decoding patterns are used. The optimized design of coded masks is critical for the performance of this technique and will depend on the characteristics of the imaging beam. In this work, Monte Carlo (MCNP) simulations were utilized to explore the needed modifications to the PULSTAR thermal neutron beam to support coded imaging techniques. In addition, an assessment of coded mask design has been performed. The simulations indicated that a 12 inch single crystal sapphire filter is suited for such an application at the PULSTAR beam in terms of maximizing flux with good neutron-to-gamma ratio. Computational simulations demonstrate the feasibility of correlation reconstruction methods on neutron transmission imaging. A gadolinium aperture with thickness of 500 m was used to construct the mask using a 38 34 URA pattern. A test experiment using such a URA design has been conducted and the point spread function of the system has been measured.

Xiao, Ziyu [North Carolina State University] [North Carolina State University; Mishra, Kaushal [North Carolina State University] [North Carolina State University; Hawari, Ayman [North Carolina State University] [North Carolina State University; Bingham, Philip R [ORNL] [ORNL; Bilheux, Hassina Z [ORNL] [ORNL; Tobin Jr, Kenneth William [ORNL] [ORNL

2010-01-01

61

ALS beamlines for independent investigators: A summary of the capabilities and characteristics of beamlines at the ALS  

SciTech Connect

There are two mods of conducting research at the ALS: To work as a member of a participating research team (PRT). To work as a member of a participating research team (PRT); to work as an independent investigator; PRTs are responsible for building beamlines, end stations, and, in some cases, insertion devices. Thus, PRT members have privileged access to the ALS. Independent investigators will use beamline facilities made available by PRTs. The purpose of this handbook is to describe these facilities.

Not Available

1992-08-01

62

RACE, CODE OF THE STREET, AND VIOLENT DELINQUENCY: A MULTILEVEL INVESTIGATION OF NEIGHBORHOOD STREET CULTURE AND INDIVIDUAL NORMS OF VIOLENCE*  

PubMed Central

The study outlined in this article drew on Elijah Anderson’s (1999) code of the street perspective to examine the impact of neighborhood street culture on violent delinquency. Using data from more than 700 African American adolescents, we examined 1) whether neighborhood street culture predicts adolescent violence above and beyond an adolescent’s own street code values and 2) whether neighborhood street culture moderates individual-level street code values on adolescent violence. Consistent with Anderson’s hypotheses, neighborhood street culture significantly predicts violent delinquency independent of individual-level street code effects. Additionally, neighborhood street culture moderates individual-level street code values on violence in neighborhoods where the street culture is widespread. In particular, the effect of street code values on violence is enhanced in neighborhoods where the street culture is endorsed widely.

Stewart, Eric A.; Simons, Ronald L.

2011-01-01

63

Flight Investigation of Prescribed Simultaneous Independent Surface Excitations for Real-Time Parameter Identification  

NASA Technical Reports Server (NTRS)

Near real-time stability and control derivative extraction is required to support flight demonstration of Intelligent Flight Control System (IFCS) concepts being developed by NASA, academia, and industry. Traditionally, flight maneuvers would be designed and flown to obtain stability and control derivative estimates using a postflight analysis technique. The goal of the IFCS concept is to be able to modify the control laws in real time for an aircraft that has been damaged in flight. In some IFCS implementations, real-time parameter identification (PID) of the stability and control derivatives of the damaged aircraft is necessary for successfully reconfiguring the control system. This report investigates the usefulness of Prescribed Simultaneous Independent Surface Excitations (PreSISE) to provide data for rapidly obtaining estimates of the stability and control derivatives. Flight test data were analyzed using both equation-error and output-error PID techniques. The equation-error PID technique is known as Fourier Transform Regression (FTR) and is a frequency-domain real-time implementation. Selected results were compared with a time-domain output-error technique. The real-time equation-error technique combined with the PreSISE maneuvers provided excellent derivative estimation in the longitudinal axis. However, the PreSISE maneuvers as presently defined were not adequate for accurate estimation of the lateral-directional derivatives.

Moes, Timothy R.; Smith, Mark S.; Morelli, Eugene A.

2003-01-01

64

Investigation of Beam-RF Interactions in Twisted Waveguide Accelerating Structures Using Beam Tracking Codes  

SciTech Connect

Investigations of the RF properties of certain twisted waveguide structures show that they support favorable accelerating fields. This makes them potential candidates for accelerating cavities. Using the particle tracking code, ORBIT, We examine the beam - RF interaction in the twisted cavity structures to understand their beam transport and acceleration properties. The results will show the distinctive properties of these new structures for particle transport and acceleration, which have not been previously analyzed.

Holmes, Jeffrey A [ORNL] [ORNL; Zhang, Yan [ORNL] [ORNL; Kang, Yoon W [ORNL] [ORNL; Galambos, John D [ORNL] [ORNL; Hassan, Mohamed H [ORNL] [ORNL; Wilson, Joshua L [ORNL] [ORNL

2009-01-01

65

Two mitochondrial genomes from the families Bethylidae and Mutillidae: Independent rearrangement of protein-coding genes and higher-level phylogeny of the Hymenoptera.  

PubMed

In animal mitochondrial genomes, gene arrangements are usually conserved across major lineages but might be rearranged within derived groups, and might provide valuable phylogenetic characters. Here, we sequenced the mitochondrial genomes of Cephalonomia gallicola (Chrysidoidea: Bethylidae) and Wallacidia oculata (Vespoidea: Mutillidae). In Cephalonomia at least 11 tRNA and 2 protein-coding genes were rearranged, which is the first report of protein-coding gene rearrangements in the Aculeata. In the Hymenoptera, three types of protein-coding gene rearrangement events occur, i.e. reversal, transposition and reverse transposition. Venturia (Ichneumonidae) had the greatest number of common intervals with the ancestral gene arrangement pattern, whereas Philotrypesis (Agaonidae) had the fewest. The most similar rearrangement patterns are shared between Nasonia (Pteromalidae) and Philotrypesis, whereas the most differentiated rearrangements occur between Cotesia (Braconidae) and Philotrypesis. It is clear that protein-coding gene rearrangements in the Hymenoptera are evolutionarily independent across the major lineages but are conserved within groups such as the Chalcidoidea. Phylogenetic analyses supported the sister-group relationship of Orrussoidea and Apocrita, Ichneumonoidea and Aculeata, Vespidae and Apoidea, and the paraphyly of Vespoidea. The Evaniomorpha and phylogenetic relationships within Aculeata remain controversial, with discrepancy between analyses using protein-coding and RNA genes. PMID:24704304

Wei, Shu-Jun; Li, Qian; van Achterberg, Kees; Chen, Xue-Xin

2014-08-01

66

Geochemical and isotopic investigations on groundwater residence time and flow in the Independence Basin, Mexico  

NASA Astrophysics Data System (ADS)

The Independence Basin in the semi-arid Guanajuato state of central Mexico is facing serious groundwater resources deficiency due to an increasing demand linked to a rapid population growth and agricultural development. This problem is aggravated by an inadequate evaluation of groundwater resources in the region. Geochemistry and isotopic tracers were used in order to investigate the groundwater flow system and estimate the groundwater residence time. The groundwater is characterized by low salinity with some exceptions associated to a contribution of more saline groundwater from deep formations. The predominant reactions are CO 2 gas dissolution, carbonate dissolution, albite weathering, kaolinite and chalcedony precipitation. Six principal hydrochemical zones were recognized, which provided information on plausible recharge sources and groundwater chemical evolution. The 14C concentration varies between 19 and 94 pmc. The high 14C values indicating recent recharge are observed at the basin margins and a trend to lower 14C values is observed along the modern groundwater flow paths. The groundwater residence time according to radiocarbon estimations ranges between recent and ˜11 ka. The residence time distribution matches the regional important discharge zones west in the basin center (from Dolores Hidalgo and southwest from Doctor Mora). Hydrochemical tracers are in general agreement with the predeveloped and current hydraulic-head configuration, however, show some inconsistencies with the predeveloped head in the downgradient areas, which means that the impact by gradually increasing groundwater extraction during the last decades is reflected on radiocarbon age distribution. Geochemical evidences imply that the recharge input from the northern basin area is insignificant.

Mahlknecht, J.; Gárfias-Solis, J.; Aravena, R.; Tesch, R.

2006-06-01

67

An investigation on the capabilities of the PENELOPE MC code in nanodosimetry  

SciTech Connect

The Monte Carlo (MC) method has been widely implemented in studies of radiation effects on human genetic material. Most of these works have used specific-purpose MC codes to simulate radiation transport in condensed media. PENELOPE is one of the general-purpose MC codes that has been used in many applications related to radiation dosimetry. Based on the fact that PENELOPE can carry out event-by-event coupled electron-photon transport simulations following these particles down to energies of the order of few tens of eV, we have decided to investigate the capacities of this code in the field of nanodosimetry. Single and double strand break probabilities due to the direct impact of {gamma} rays originated from Co{sup 60} and Cs{sup 137} isotopes and characteristic x-rays, from Al and C K-shells, have been determined by use of PENELOPE. Indirect damage has not been accounted for in this study. A human genetic material geometrical model has been developed, taking into account five organizational levels. In an article by Friedland et al. [Radiat. Environ. Biophys. 38, 39-47 (1999)], a specific-purpose MC code and a very sophisticated DNA geometrical model were used. We have chosen that work as a reference to compare our results. Single and double strand-break probabilities obtained here underestimate those reported by Friedland and co-workers by 20%-76% and 50%-60%, respectively. However, we obtain RBE values for Cs{sup 137}, Al{sub K} and C{sub K} radiations in agreement with those reported in previous works [Radiat. Environ. Biophys. 38, 39-47 (1999)] and [Phys. Med. Biol. 53, 233-244 (2008)]. Some enhancements can be incorporated into the PENELOPE code to improve its results in the nanodosimetry field.

Bernal, M. A.; Liendo, J. A. [Departamento de Fisica, Universidad Simon Bolivar, P.O. Box 89000, Caracas (Venezuela, Bolivarian Republic of)

2009-02-15

68

An investigation on the capabilities of the PENELOPE MC code in nanodosimetry.  

PubMed

The Monte Carlo (MC) method has been widely implemented in studies of radiation effects on human genetic material. Most of these works have used specific-purpose MC codes to simulate radiation transport in condensed media. PENELOPE is one of the general-purpose MC codes that has been used in many applications related to radiation dosimetry. Based on the fact that PENELOPE can carry out event-by-event coupled electron-photon transport simulations following these particles down to energies of the order of few tens of eV, we have decided to investigate the capacities of this code in the field of nanodosimetry. Single and double strand break probabilities due to the direct impact of gamma rays originated from Co60 and Cs137 isotopes and characteristic x-rays, from Al and C K-shells, have been determined by use of PENELOPE. Indirect damage has not been accounted for in this study. A human genetic material geometrical model has been developed, taking into account five organizational levels. In an article by Friedland et al. [Radiat. Environ. Biophys. 38, 39-47 (1999)], a specific-purpose MC code and a very sophisticated DNA geometrical model were used. We have chosen that work as a reference to compare our results. Single and double strand-break probabilities obtained here underestimate those reported by Friedland and co-workers by 20%-76% and 50%-60%, respectively. However, we obtain RBE values for Cs137, AlK and CK radiations in agreement with those reported in previous works [Radiat. Environ. Biophys. 38, 39-47 (1999)] and [Phys. Med. Biol. 53, 233-244 (2008)]. Some enhancements can be incorporated into the PENELOPE code to improve its results in the nanodosimetry field. PMID:19292002

Bernal, M A; Liendo, J A

2009-02-01

69

Investigation of in-band transmission of both spectral amplitude coding/optical code division multiple-access and wavelength division multiplexing signals  

NASA Astrophysics Data System (ADS)

The transmission of both optical code division multiple-access (OCDMA) and wavelength division multiplexing (WDM) users on the same band is investigated. Code pulses of spectral amplitude coding (SAC)/optical code division multiple-access (CDMA) are overlaid onto a multichannel WDM system. Notch filters are utilized in order to suppress the WDM interference signals for detection of optical broadband CDMA signals. Modified quadratic congruence (MQC) codes are used as the signature codes for the SAC/OCDMA system. The proposed system is simulated and its performance in terms of both the bit-error rate and Q-factor are determined. In addition, eavesdropper probability of error-free code detection is evaluated. Our results are compared to traditional nonhybrid systems. It is concluded that the proposed hybrid scheme still achieves acceptable performance. In addition, it provides enhanced data confidentiality as compared to the scheme with SAC/OCDMA only. It is also shown that the performance of the proposed system is limited by the interference of the WDM signals. Furthermore, the simulation illustrates the tradeoff between the performance and confidentiality for authorized users.

Ashour, Isaac A. M.; Shaari, Sahbudin; Shalaby, Hossam M. H.; Menon, P. Susthitha

2011-06-01

70

A Longitudinal Investigation of Field Dependence-Independence and the Development of Formal Operational Thought.  

ERIC Educational Resources Information Center

A longitudinal study among American adolescents revealed (1) an insignificant impact of field dependence-independence on the development of formal operational thought; (2) continuous development of combinatorial reasoning and propositional logic abilities, but little increase in comprehension of proportionality; and (3) sex differences in formal…

Flexer, B.K.; Roberge, J.J.

1983-01-01

71

After a Long-Term Placement: Investigating Educational Achievement, Behaviour, and Transition to Independent Living  

ERIC Educational Resources Information Center

This study describes the transition towards independent living of 123 former fostered young people reared for long periods in a private French organisation, SOS Children's Villages. Three generations of care leavers were analysed through a postal survey and interviews. Their narratives show typical pathways after leaving care. Two-thirds became…

Dumaret, Annick-Camille; Donati, Pascale; Crost, Monique

2011-01-01

72

Investigation of Cool and Hot Executive Function in ODD/CD Independently of ADHD  

ERIC Educational Resources Information Center

Background: Children with oppositional defiant disorder/conduct disorder (ODD/CD) have shown deficits in "cool" abstract-cognitive, and "hot" reward-related executive function (EF) tasks. However, it is currently unclear to what extent ODD/CD is associated with neuropsychological deficits, independently of attention deficit hyperactivity disorder…

Hobson, Christopher W.; Scott, Stephen; Rubia, Katya

2011-01-01

73

An Investigation of Independent Child Behavior in the Open Classroom: The Classroom Attitude Observation Schedule (CAOS).  

ERIC Educational Resources Information Center

The Classroom Attitude Observation Schedule was developed and field tested for study of independent child behavior in the open classroom. Eight Head Start classrooms were used for field testing, six of which used the Tucson Early Education Model curriculum and two of which, for comparison, used local curricula. Procedures involved observing and…

Goldupp, Ocea

74

Independent Investigations of Reliability and Validity of Learning Behaviors Scale Scores: Implications for Practitioners and Future Directions  

Microsoft Academic Search

Abstract This presentation reports on the results of four independent studies that investigated the reliability and validity of Learning Behaviors Scale (LBS; McDermott, Green, Francis, & Stott, 1999) scores. The LBS is a cost and time effective, nationally normed, and unobtrusive observation measure of key learning behavior variables that influence student learning. Study 1 examined the replication of the short-term

Gary L. Canivez

75

Investigation on series of length of coding and non-coding DNA sequences of bacteria using multifractal detrended cross-correlation analysis.  

PubMed

In the framework of multifractal detrended cross-correlation analysis, we investigate characteristics of series of length of coding and non-coding DNA sequences of some bacteria and archaea. We propose the use of a multifractal cross-correlation series that can be defined for any pair of equal lengths data sequences (or time series) and that can be characterized by the full set of parameters that are attributed to any time series. Comparison between characteristics of series of length of coding and non-coding DNA sequences and of their associated multifractal cross-correlation series for selected groups is used for the identification of class affiliation of certain bacteria and archaea. The analysis is carried out using the dependence of the generalized Hurst exponent on the size of fluctuations, the shape of the singularity spectra, the shape and relative disposition of the curves of the singular measures scaling exponent and the values of the associated parameters. Empirically, we demonstrate that the series of lengths of coding and non-coding sequences as well as the associated multifractal cross-correlation series can be approximated as universal multifractals. PMID:23313335

Stan, Cristina; Cristescu, Monica Teodora; Luiza, Buimaga Iarinca; Cristescu, C P

2013-03-21

76

3D PiC code investigations of Auroral Kilometric Radiation mechanisms  

NASA Astrophysics Data System (ADS)

Efficient (~1%) electron cyclotron radio emissions are known to originate in the X mode from regions of locally depleted plasma in the Earths polar magnetosphere. These emissions are commonly referred to as the Auroral Kilometric Radiation (AKR). AKR occurs naturally in these polar regions where electrons are accelerated by electric fields into the increasing planetary magnetic dipole. Here conservation of the magnetic moment converts axial to rotational momentum forming a horseshoe distribution in velocity phase space. This distribution is unstable to cyclotron emission with radiation emitted in the X-mode. Initial studies were conducted in the form of 2D PiC code simulations [1] and a scaled laboratory experiment that was constructed to reproduce the mechanism of AKR. As studies progressed, 3D PiC code simulations were conducted to enable complete investigation of the complex interaction dimensions. A maximum efficiency of 1.25% is predicted from these simulations in the same mode and frequency as measured in the experiment. This is also consistent with geophysical observations and the predictions of theory.

Gillespie, K. M.; McConville, S. L.; Speirs, D. C.; Ronald, K.; Phelps, A. D. R.; Bingham, R.; Cross, A. W.; Robertson, C. W.; Whyte, C. G.; He, W.; Vorgul, I.; Cairns, R. A.; Kellett, B. J.

2014-05-01

77

Independent forensic autopsies in an armed conflict: investigation of the victims from Racak, Kosovo  

Microsoft Academic Search

In January 1999, a team of Finnish forensic experts under the mandate of the European Union (EU forensic expert team, EU-FET) performed forensic investigations in a sovereign state, in Kosovo, the Federal Republic of Yugoslavia (FRY). The team served as a neutral participant in the forensic investigation of victims of an incident at Racak, which was receiving considerable international attention.

J. Rainio; K. Lalu; A. Penttilä

2001-01-01

78

Investigation of insulin resistance in narcoleptic patients: dependent or independent of body mass index?  

PubMed Central

Background: Narcolepsy is a severe sleep-wake cycle disorder resulting in most cases from a lack of orexin, the energy balance-regulating hormone. Narcoleptic patients have been reported to suffer from an excess morbidity of Type 2 diabetes, even after correction for their often elevated body mass index. Methods: To explore whether narcolepsy is specifically associated with a propensity to develop insulin resistance, we measured fasting glucose, insulin, and intact proinsulin levels in 43 narcoleptic patients and 47 controls matched for body mass index and age. The proinsulin-to-insulin ratio was calculated. Insulin resistance was determined using the homeostatic model assessment method. Results: Narcoleptic patients did not show elevated insulin resistance parameters. Conclusion: In contrast with earlier reports, we found no evidence that narcolepsy specifically elevates the risk of insulin resistance (and consequently of type 2 diabetes) independently of body mass index.

Engel, Alice; Helfrich, Jana; Manderscheid, Nina; Musholt, Petra B; Forst, Thomas; Pfutzner, Andreas; Dahmen, Norbert

2011-01-01

79

Long non-coding RNA HOTAIR is an independent prognostic marker of metastasis in estrogen receptor-positive primary breast cancer.  

PubMed

Expression of HOX transcript antisense intergenic RNA (HOTAIR)--a long non-coding RNA--has been examined in a variety of human cancers, and overexpression of HOTAIR is correlated with poor survival among breast, colon, and liver cancer patients. In this retrospective study, we examine HOTAIR expression in 164 primary breast tumors, from patients who do not receive adjuvant treatment, in a design that is paired with respect to the traditional prognostic markers. We show that HOTAIR expression differs between patients with or without a metastatic endpoint, respectively. Survival analysis shows that high HOTAIR expression in primary tumors is significantly associated with worse prognosis independent of prognostic markers (P = 0.012, hazard ratio (HR) 1.747). This association is even stronger when looking only at estrogen receptor (ER)-positive tumor samples (P = 0.0086, HR 1.985). In ER-negative tumor samples, we are not able to detect a prognostic value of HOTAIR expression, probably due to the limited sample size. These results are successfully validated in an independent dataset with similar associations (P = 0.018, HR 1.825). In conclusion, our findings suggest that HOTAIR expression may serve as an independent biomarker for the prediction of the risk of metastasis in ER-positive breast cancer patients. PMID:24258260

Sørensen, Kristina P; Thomassen, Mads; Tan, Qihua; Bak, Martin; Cold, Søren; Burton, Mark; Larsen, Martin J; Kruse, Torben A

2013-12-01

80

Culture-Dependent and -Independent Investigations of Microbial Diversity on Urinary Catheters  

PubMed Central

Catheter-associated urinary tract infection is caused by bacteria, which ascend the catheter along its external or internal surface to the bladder and subsequently develop into biofilms on the catheter and uroepithelium. Antibiotic-treated bacteria and bacteria residing in biofilm can be difficult to culture. In this study we used culture-based and 16S rRNA gene-based culture-independent methods (fingerprinting, cloning, and pyrosequencing) to determine the microbial diversity of biofilms on 24 urinary catheters. Most of the patients were catheterized for <30 days and had undergone recent antibiotic treatment. In addition, the corresponding urine samples for 16 patients were cultured. We found that gene analyses of the catheters were consistent with cultures of the corresponding urine samples for the presence of bacteria but sometimes discordant for the identity of the species. Cultures of catheter tips detected bacteria more frequently than urine cultures and gene analyses; coagulase-negative staphylococci were, in particular, cultured much more often from catheter tips, indicating potential contamination of the catheter tips during sampling. The external and internal surfaces of 19 catheters were separately analyzed by molecular methods, and discordant results were found in six catheters, suggesting that bacterial colonization intra- and extraluminally may be different. Molecular analyses showed that most of the species identified in this study were known uropathogens, and infected catheters were generally colonized by one to two species, probably due to antibiotic usage and short-term catheterization. In conclusion, our data showed that culture-independent molecular methods did not detect bacteria from urinary catheters more frequently than culture-based methods.

Xu, Yijuan; Moser, Claus; Al-Soud, Waleed Abu; S?rensen, S?ren; H?iby, Niels; Nielsen, Per Halkjaer

2012-01-01

81

Final Report of the Independent Counsel for Iran/Contra Matters. Volume 1. Investigations and Prosecutions.  

National Technical Information Service (NTIS)

Table of Contents: Letter of Transmittal; Executive Summary; Summary of Prosecutions; Part I-The Underlying Facts; Part II-History of the Investigation; Chronology of Key Public Developments; Part III-The Operational Conspiracy: A Legal Analysis; Part IV-...

L. E. Walsh

1993-01-01

82

Nye County Nuclear Waste Repository Project Office independent scientific investigations program annual report, May 1997--April 1998  

SciTech Connect

This annual summary report, prepared by the Nye County Nuclear Waste Repository Project Office (NWRPO), summarizes the activities that were performed during the period from May 1, 1997 to April 30, 1998. These activities were conducted in support of the Independent Scientific Investigation Program (ISIP) of Nye County at the Yucca Mountain Site (YMS). The Nye County NWRPO is responsible for protecting the health and safety of the Nye County residents. NWRPO`s on-site representative is responsible for designing and implementing the Independent Scientific Investigation Program (ISIP). Major objectives of the ISIP include: Investigating key issues related to conceptual design and performance of the repository that can have major impact on human health, safety, and the environment; identifying areas not being addressed adequately by the Department of Energy (DOE). Nye County has identified several key scientific issues of concern that may affect repository design and performance which were not being adequately addressed by DOE. Nye County has been conducting its own independent study to evaluate the significance of these issues. This report summarizes the results of monitoring from two boreholes and the Exploratory Studies Facility (ESF) tunnel that have been instrumented by Nye County since March and April of 1995. The preliminary data and interpretations presented in this report do not constitute and should not be considered as the official position of Nye County. The ISIP presently includes borehole and tunnel instrumentation, monitoring, data analysis, and numerical modeling activities to address the concerns of Nye County.

NONE

1998-07-01

83

Culture-Dependent and -Independent Methods To Investigate the Microbial Ecology of Italian Fermented Sausages  

PubMed Central

In this study, the microbial ecology of three naturally fermented sausages produced in northeast Italy was studied by culture-dependent and -independent methods. By plating analysis, the predominance of lactic acid bacteria populations was pointed out, as well as the importance of coagulase-negative cocci. Also in the case of one fermentation, the fecal enterocci reached significant counts, highlighting their contribution to the particular transformation process. Yeast counts were higher than the detection limit (>100 CFU/g) in only one fermented sausage. Analysis of the denaturing gradient gel electrophoresis (DGGE) patterns and sequencing of the bands allowed profiling of the microbial populations present in the sausages during fermentation. The bacterial ecology was mainly characterized by the stable presence of Lactobacillus curvatus and Lactobacillus sakei, but Lactobacillus paracasei was also repeatedly detected. An important piece of evidence was the presence of Lactococcus garvieae, which clearly contributed in two fermentations. Several species of Staphylococcus were also detected. Regarding other bacterial groups, Bacillus sp., Ruminococcus sp., and Macrococcus caseolyticus were also identified at the beginning of the transformations. In addition, yeast species belonging to Debaryomyces hansenii, several Candida species, and Willopsis saturnus were observed in the DGGE gels. Finally, cluster analysis of the bacterial and yeast DGGE profiles highlighted the uniqueness of the fermentation processes studied.

Rantsiou, Kalliopi; Urso, Rosalinda; Iacumin, Lucilla; Cantoni, Carlo; Cattaneo, Patrizia; Comi, Giuseppe; Cocolin, Luca

2005-01-01

84

A model-independent investigation on quasi-degenerate neutrino mass models and their significance  

NASA Astrophysics Data System (ADS)

The prediction of possible hierarchy of neutrino masses mostly depends on the model chosen. Dissociating the ?-? interchange symmetry from discrete flavor symmetry based models, makes the neutrino mass matrix less predictive and motivates one to seek the answer from different phenomenological frameworks. This insists on proper parametrization of the neutrino mass matrices concerning individual hierarchies. In this work, an attempt has been made to study the six different cases of quasi-degenerate (QDN) neutrino models with mass matrices, mLL? parametrized with two free parameters (?,?), standard Wolfenstein parameter (?) and input mass scale, m0˜0.08 eV. We start with a ?-? symmetric neutrino mass matrix followed by a correction from charged lepton sector. The parametrization emphasizes on the existence of four independent texture zero building blocks common to all the QDN models under ?-? symmetric framework and is found to be invariant under any choice of solar angle. In our parametrization, solar angle is controlled from neutrino sector whereas the charged lepton sector drives the reactor and atmospheric mixing angles. The individual models are tested in the framework of oscillation experiments, cosmological observation and future experiments involving ?-decay and 0??? experiments, and any reason to discard the QDN mass models with relatively lower mass is unfounded. Although the QDNH-Type IA model shows strong preference for sin2?12=0.32, yet this is not sufficient to rule out the other models. The present work leaves a scope to extend the search of most favorable QDN mass model from observed baryon asymmetry of the Universe.

Roy, Subhankar; Singh, N. Nimai

2013-12-01

85

Independent forensic autopsies in an armed conflict: investigation of the victims from Racak, Kosovo.  

PubMed

In January 1999, a team of Finnish forensic experts under the mandate of the European Union (EU forensic expert team, EU-FET) performed forensic investigations in a sovereign state, in Kosovo, the Federal Republic of Yugoslavia (FRY). The team served as a neutral participant in the forensic investigation of victims of an incident at Racak, which was receiving considerable international attention. The Finnish team performed forensic autopsies, monitored forensic autopsies performed by local experts and verified findings of earlier executed autopsies. The victims had sustained varying numbers of gunshot wounds, which were established to be the cause of death. The manner of death remained undetermined by the EU-FET, because the scene investigation and the chain of custody for the bodies from the site of the incident to the autopsy were impossible to verify by the team. The events at Racak were the first of those leading to charges by the International Criminal Tribunal for the former Yugoslavia (ICTY) against the highest authorities in power in the FRY for crimes against humanity and violations of the laws or customs of war. PMID:11182269

Rainio, J; Lalu, K; Penttilä, A

2001-02-15

86

Further Investigation of Acoustic Propagation Codes for Three-Dimensional Geometries  

NASA Technical Reports Server (NTRS)

The ability to predict fan noise within complex three-dimensional aircraft engine nacelle geometries is a valuable tool in designing and assessing low-noise concepts. This work begins a systematic study to identify the areas of the design space in which propagation codes of varying fidelity may be used effectively to provide efficient design and assessment. An efficient lower-fidelity code is used in conjunction with two higher-fidelity, more computationally intensive methods to solve benchmark problems of increasing complexity. The codes represent a small sampling of the current propagation codes available or under development. Results of this initial study indicate that the lower-fidelity code provides satisfactory results for cases involving low to moderate attenuation rates, whereas, the two higher-fidelity codes perform well across the range of problems.

Nark, Douglas M.; Watson, Willie R.; Jones, Michael G.

2006-01-01

87

Investigation of Different Constituent Encoders in a Turbo-code Scheme for Reduced Decoder Complexity  

NASA Technical Reports Server (NTRS)

A large number of papers have been published attempting to give some analytical basis for the performance of Turbo-codes. It has been shown that performance improves with increased interleaver length. Also procedures have been given to pick the best constituent recursive systematic convolutional codes (RSCC's). However testing by computer simulation is still required to verify these results. This thesis begins by describing the encoding and decoding schemes used. Next simulation results on several memory 4 RSCC's are shown. It is found that the best BER performance at low E(sub b)/N(sub o) is not given by the RSCC's that were found using the analytic techniques given so far. Next the results are given from simulations using a smaller memory RSCC for one of the constituent encoders. Significant reduction in decoding complexity is obtained with minimal loss in performance. Simulation results are then given for a rate 1/3 Turbo-code with the result that this code performed as well as a rate 1/2 Turbo-code as measured by the distance from their respective Shannon limits. Finally the results of simulations where an inaccurate noise variance measurement was used are given. From this it was observed that Turbo-decoding is fairly stable with regard to noise variance measurement.

Kwatra, S. C.

1998-01-01

88

Investigation of independence in inter-animal tumor-type occurrences within the NTP rodent-bioassay database  

SciTech Connect

Statistically significant elevation in tumor incidence at multiple histologically distinct sites is occasionally observed among rodent bioassays of chemically induced carcinogenesis. If such data are to be relied on (as they have, e.g., by the US EPA) for quantitative cancer potency assessment, their proper analysis requires a knowledge of the extent to which multiple tumor-type occurrences are independent or uncorrelated within individual bioassay animals. Although difficult to assess in a statistically rigorous fashion, a few significant associations among tumor-type occurrences in rodent bioassays have been reported. However, no comprehensive studies of animal-specific tumor-type occurrences at death or sacrifice have been conducted using the extensive set of available NTP rodent-bioassay data, on which most cancer-potency assessment for environmental chemicals is currently based. This report presents the results of such an analysis conducted on behalf of the National Research Council`s Committee on Risk Assessment for Hazardous Air Pollutants. Tumor-type associations among individual animals were examined for {approximately}2500 to 3000 control and {approximately}200 to 600 treated animals using pathology data from 62 B6C3F1 mouse studies and 61 F/344N rat studies obtained from a readily available subset of the NTP carcinogenesis bioassay database. No evidence was found for any large correlation in either the onset probability or the prevalence-at-death or sacrifice of any tumor-type pair investigated in control and treated rats and niece, although a few of the small correlations present were statistically significant. Tumor-type occurrences were in most cases nearly independent, and departures from independence, where they did occur, were small. This finding is qualified in that tumor-type onset correlations were measured only indirectly, given the limited nature of the data analyzed.

Bogen, K.T. [Lawrence Livermore National Lab., CA (United States); Seilkop, S. [Analytical Sciences, Inc., Durham, NC (United States)

1993-05-01

89

Performance Investigation of STBC-OFDM With Code-Division Multiplexing in Time-Varying Channels  

Microsoft Academic Search

Orthogonal frequency division multiplexing (OFDM) is sensitive to carrier frequency offset and channel estimation error, which destroy the subcarrier orthogonality and give rise to intercarrier interference (ICI). This paper addresses the performance degradation due to imperfect parameters in an orthogonal frequency and code division multiplexing (OFDM-CDM) system with multiple transmit antennas. For the performance evaluation, the average bit error rate

Younghwan You; Mi-Jeong Kim; Sung-Kwon Hong; Intae Hwang; Hyoungkyu Song

2004-01-01

90

Investigating the semantic interoperability of laboratory data exchanged using LOINC codes in three large institutions.  

PubMed

LOINC codes are seeing increased use in many organizations. In this study, we examined the barriers to semantic interoperability that still exist in electronic data exchange of laboratory results even when LOINC codes are being used as the observation identifiers. We analyzed semantic interoperability of laboratory data exchanged using LOINC codes in three large institutions. To simplify the analytic process, we divided the laboratory data into quantitative and non-quantitative tests. The analysis revealed many inconsistencies even when LOINC codes are used to exchange laboratory data. For quantitative tests, the most frequent problems were inconsistencies in the use of units of measure: variations in the strings used to represent units (unrecognized synonyms), use of units that result in different magnitudes of the numeric quantity, and missing units of measure. For non-quantitative tests, the most frequent problems were acronyms/synonyms, different classes of elements in enumerated lists, and the use of free text. Our findings highlight the limitations of interoperability in current laboratory reporting. PMID:22195138

Lin, Ming-Chin; Vreeman, Daniel J; Huff, Stanley M

2011-01-01

91

Preliminary investigation of acoustic bar codes for short-range underwater communications  

NASA Astrophysics Data System (ADS)

In March 2005, underwater acoustic communications experiments were carried out from the DRDC Atlantic research vessel CFAV QUEST. A battery-operated BATS20 transmitter and a broadband barrel-stave flextensional transducer were used to broadcast noise containing acoustic bar code (ABC) information. The ABCs are silent frequency bands of fixed duration that resemble retail bar codes when viewed in a spectrogram. Two sites were selected for the experiments. The first was a shallow-water area west of the Berry Islands in the Bahamas, and the second was a deep-water site south of the Western Bank on the Scotian Shelf. Two receiver systems were deployed; autonomous, variable-buoyancy Stealth Buoys resting on the bottom at the shallow site, and drifting AN/SSQ-53F sonobuoys fitted with GPS at the deep site. Results from these experiments will be presented and future work will be discussed.

Jones, Dennis F.

2005-09-01

92

Investigating the impact of the cielo cray XE6 architecture on scientific application codes.  

SciTech Connect

Cielo, a Cray XE6, is the Department of Energy NNSA Advanced Simulation and Computing (ASC) campaign's newest capability machine. Rated at 1.37 PFLOPS, it consists of 8,944 dual-socket oct-core AMD Magny-Cours compute nodes, linked using Cray's Gemini interconnect. Its primary mission objective is to enable a suite of the ASC applications implemented using MPI to scale to tens of thousands of cores. Cielo is an evolutionary improvement to a successful architecture previously available to many of our codes, thus enabling a basis for understanding the capabilities of this new architecture. Using three codes strategically important to the ASC campaign, and supplemented with some micro-benchmarks that expose the fundamental capabilities of the XE6, we report on the performance characteristics and capabilities of Cielo.

Rajan, Mahesh; Barrett, Richard; Pedretti, Kevin Thomas Tauke; Doerfler, Douglas W.; Vaughan, Courtenay Thomas

2010-12-01

93

An Investigation of Two Acoustic Propagation Codes for Three-Dimensional Geometries  

NASA Technical Reports Server (NTRS)

The ability to predict fan noise within complex three-dimensional aircraft engine nacelle geometries is a valuable tool in studying low-noise designs. Recent years have seen the development of aeroacoustic propagation codes using various levels of approximation to obtain such a capability. In light of this, it is beneficial to pursue a design paradigm that incorporates the strengths of the various tools. The development of a quasi-3D methodology (Q3D-FEM) at NASA Langley has brought these ideas to mind in relation to the framework of the CDUCT-LaRC acoustic propagation and radiation tool. As more extensive three dimensional codes become available, it would seem appropriate to incorporate these tools into a framework similar to CDUCT-LaRC and use them in a complementary manner. This work focuses on such an approach in beginning the steps toward a systematic assessment of the errors, and hence the trade-offs, involved in the use of these codes. To illustrate this point, CDUCT-LaRC was used to study benchmark hardwall duct problems to quantify errors caused by wave propagation in directions far removed from that defined by the parabolic approximation. Configurations incorporating acoustic treatment were also studied with CDUCT-LaRC and Q3D-FEM. The cases presented show that acoustic treatment diminishes the effects of CDUCT-LaRC phase error as the solutions are attenuated. The results of the Q3D-FEM were very promising and matched the analytic solution very well. Overall, these tests were meant to serve as a step toward the systematic study of errors inherent in the propagation module of CDUCT-LaRC, as well as an initial test of the higher fidelity Q3D-FEM code.

Nark, D. M.; Watson, W. R.; Jones, M. G.

2005-01-01

94

Versatile code DLAYZ for investigating population kinetics and radiative properties of plasmas in non-local thermodynamic equilibrium  

NASA Astrophysics Data System (ADS)

A versatile code DLAYZ based on collisional-radiative model is developed for investigating the population kinetics and radiative properties of plasmas in non-local thermodynamic equilibrium. DLAYZ is implemented on the detailed level accounting (DLA) approach and can be extended to detailed configuration accounting (DCA) and hybrid DLA/DCA approaches. The code can treat both steady state and time-dependent problems. The implementation of the main modules of DLAYZ is discussed in detail including atomic data, rates, population distributions and radiative properties modules. The complete set of basic atomic data is obtained using relativistic quantum mechanics. For dense plasmas, the basic atomic data with plasma screening effects can be obtained. The populations are obtained by solving the coupled rate equations, which are used to calculate the radiative properties. A parallelized version is implemented in the code to treat the large-scale rate equations. Two illustrative examples of a steady state case for carbon plasmas and a time-dependent case for the relaxation of a K-shell excited argon are employed to show the main features of the present code.

Gao, Cheng; Zeng, Jiaolong; Li, Yongqiang; Jin, Fengtao; Yuan, Jianmin

2013-09-01

95

Investigation on Coding Method of Dental X-ray Image for Integrated Hospital Information System  

NASA Astrophysics Data System (ADS)

Recently, medical information system in dental field goes into digital system. In the system, X-ray image can be taken in digital modality and input to the system directly. Consequently, it is easy to combine the image data with alpha-numerical data which are stored in the conventional medical information system. It is useful to manipulate alpha-numerical data and image data simultaneously. The purpose of this research is to develop a new coding method for dental X-ray image. The method enables to reduce a disk space to store the images and transmit the images through Internet or LAN lightly. I attempt to apply multi-resolution analysis (wavelet transform) to accomplish the purpose. Proposed method achieves low bit-rate compared with conventional method.

Seki, Takashi; Hamamoto, Kazuhiko

96

Investigation of mixing in a turbofan exhaust duct. II Computer code application and verification  

NASA Technical Reports Server (NTRS)

A three-dimensional analysis of turbofan forced mixer nozzle aerodynamics demonstrates that the complex flow structure is dominated by geometrically induced secondary flow rather than by turbulence. The test apparatus consisted of a fixed upstream model section and a rotating shroud. The Mach number of the fan and core streams at the mixing plane (lobe exit) was 0.45, the bypass ratio was about 4, and the Reynolds number based on the shroud radius was 1,100,000. The three velocity components near the exit plane of the lobes were measured using flow angularity probes to provide information about the mixer inflow conditions for turbulent computations. The validity of a previous computer code was demonstrated in a comparison of the nozzle exit temperature data with the computed temperature distributions. The mechanism most responsible for the generation of secondary flow within the lobes is due to the turning of the fan and core streams in opposite radial directions.

Povinelli, L. A.; Anderson, B. H.

1984-01-01

97

MDMC2: A molecular dynamics code for investigating the fragmentation dynamics of multiply charged clusters  

NASA Astrophysics Data System (ADS)

MDMC2 is a parallel code for performing molecular dynamics simulations on multiply charged clusters. It is a valuable complement to MCMC2, a Monte Carlo program devoted to Monte Carlo simulations of multiply charged clusters in the NVT ensemble (Bonhommeau and Gaigeot, 2013). Both MCMC2 and MDMC2 codes employ a mesoscopic coarse-grained simplified representation of the clusters (or droplets): these clusters are composed of neutral and charged spherical particles/grains that may be polarisable. One grain can be either neutral or charged. The interaction potential is a sum of 2-body Lennard-Jones potentials (main cohesive contribution) and electrostatic terms (repulsive contribution), possibly supplemented by N-body polarisation interactions. There is no restriction imposed on the values of the particle charges and/or polarisabilities. An external field can also be applied to the whole system. The derivatives of the potential energy-surface are determined analytically which ensures an accurate integration of classical equations of motion by a velocity Verlet algorithm. Conservation rules, such as energy conservation or centre-of-mass linear momentum conservation, can be steadily checked during the simulation. The program also provides some statistical information on the run and configuration files that can be used for data post-treatment. MDMC2 is provided with a serial conjugate gradient program, called CGMC2, that uses the same analytical derivatives as MDMC2 and was found useful to probe the minima of the energy landscape explored during Monte Carlo or molecular dynamics simulations performed on multiply charged clusters.

Bonhommeau, David A.; Gaigeot, Marie-Pierre

2014-02-01

98

Investigating What Undergraduate Students Know About Science: Results from Complementary Strategies to Code Open-Ended Responses  

NASA Astrophysics Data System (ADS)

This paper presents new findings from an ongoing study of undergraduate student science literacy. Using data drawn from a 22 year project and over 11,000 student responses, we present how students' word usage in open-ended responses relates to what it means to study something scientifically. Analysis of students' responses show that they easily use words commonly associated with science, such as hypothesis, study, method, test, and experiment; but do these responses use scientific words knowledgeably? As with many multifaceted disciplines, demonstration of comprehension varies. This paper presents three different ways that student responses have been coded to investigate their understanding of science; 1) differentiating quality of a response with a coding scheme; 2) using word counting as an indicator of overall response strength; 3) responses are coded for quality of students' response. Building on previous research, comparison of science literacy and open-ended responses demonstrates that knowledge of science facts and vocabulary does not indicate a comprehension of the concepts behind these facts and vocabulary. This study employs quantitative and qualitative methods to systematically determine frequency and meaning of responses to standardized questions, and illustrates how students are able to demonstrate a knowledge of vocabulary. However, this knowledge is not indicative of conceptual understanding and poses important questions about how we assess students' understandings of science.

Tijerino, K.; Buxner, S.; Impey, C.; CATS

2013-04-01

99

Investigating protein-coding sequence evolution with probabilistic codon substitution models.  

PubMed

This review is motivated by the true explosion in the number of recent studies both developing and ameliorating probabilistic models of codon evolution. Traditionally parametric, the first codon models focused on estimating the effects of selective pressure on the protein via an explicit parameter in the maximum likelihood framework. Likelihood ratio tests of nested codon models armed the biologists with powerful tools, which provided unambiguous evidence for positive selection in real data. This, in turn, triggered a new wave of methodological developments. The new generation of models views the codon evolution process in a more sophisticated way, relaxing several mathematical assumptions. These models make a greater use of physicochemical amino acid properties, genetic code machinery, and the large amounts of data from the public domain. The overview of the most recent advances on modeling codon evolution is presented here, and a wide range of their applications to real data is discussed. On the downside, availability of a large variety of models, each accounting for various biological factors, increases the margin for misinterpretation; the biological meaning of certain parameters may vary among models, and model selection procedures also deserve greater attention. Solid understanding of the modeling assumptions and their applicability is essential for successful statistical data analysis. PMID:18922761

Anisimova, Maria; Kosiol, Carolin

2009-02-01

100

Theoretical models and simulation codes to investigate bystander effects and cellular communication at low doses  

NASA Astrophysics Data System (ADS)

Astronauts in space are continuously exposed to low doses of ionizing radiation from Galactic Cosmic Rays During the last ten years the effects of low radiation doses have been widely re-discussed following a large number of observations on the so-called non targeted effects in particular bystander effects The latter consist of induction of cytogenetic damage in cells not directly traversed by radiation most likely as a response to molecular messengers released by directly irradiated cells Bystander effects which are observed both for lethal endpoints e g clonogenic inactivation and apoptosis and for non-lethal ones e g mutations and neoplastic transformation tend to show non-linear dose responses This might have significant consequences in terms of low-dose risk which is generally calculated on the basis of the Linear No Threshold hypothesis Although the mechanisms underlying bystander effects are still largely unknown it is now clear that two types of cellular communication i e via gap junctions and or release of molecular messengers into the extracellular environment play a fundamental role Theoretical models and simulation codes can be of help in elucidating such mechanisms In the present paper we will review different available modelling approaches including one that is being developed at the University of Pavia The focus will be on the different assumptions adopted by the various authors and on the implications of such assumptions in terms of non-targeted radiobiological damage and more generally low-dose

Ballarini, F.; Alloni, D.; Facoetti, A.; Mairani, A.; Nano, R.; Ottolenghi, A.

101

National evaluation of the benefits and risks of greater structuring and coding of the electronic health record: exploratory qualitative investigation  

PubMed Central

Objective We aimed to explore stakeholder views, attitudes, needs, and expectations regarding likely benefits and risks resulting from increased structuring and coding of clinical information within electronic health records (EHRs). Materials and methods Qualitative investigation in primary and secondary care and research settings throughout the UK. Data were derived from interviews, expert discussion groups, observations, and relevant documents. Participants (n=70) included patients, healthcare professionals, health service commissioners, policy makers, managers, administrators, systems developers, researchers, and academics. Results Four main themes arose from our data: variations in documentation practice; patient care benefits; secondary uses of information; and informing and involving patients. We observed a lack of guidelines, co-ordination, and dissemination of best practice relating to the design and use of information structures. While we identified immediate benefits for direct care and secondary analysis, many healthcare professionals did not see the relevance of structured and/or coded data to clinical practice. The potential for structured information to increase patient understanding of their diagnosis and treatment contrasted with concerns regarding the appropriateness of coded information for patients. Conclusions The design and development of EHRs requires the capture of narrative information to reflect patient/clinician communication and computable data for administration and research purposes. Increased structuring and/or coding of EHRs therefore offers both benefits and risks. Documentation standards within clinical guidelines are likely to encourage comprehensive, accurate processing of data. As data structures may impact upon clinician/patient interactions, new models of documentation may be necessary if EHRs are to be read and authored by patients.

Morrison, Zoe; Fernando, Bernard; Kalra, Dipak; Cresswell, Kathrin; Sheikh, Aziz

2014-01-01

102

Groundwater flow analyses in preliminary site investigations. Modelling strategy and computer codes.  

National Technical Information Service (NTIS)

The analyses of groundwater flow comprised a part of the preliminary site investigations which were carried out by Teollisuuden Voima Oy (TVO) for five areas in Finland during 1987 -1992. The main objective of the flow analyses was to characterize groundw...

V. Taivassalo L. Koskinen K. Meling

1994-01-01

103

Histone H4 acetylation distinguishes coding regions of the human genome from heterochromatin in a differentiation-dependent but transcription-independent manner.  

PubMed Central

By immunoprecipitation of chromatin fragments from cultured human HL-60 cells with antibodies specific for H4 acetylated at specific lysine residues we have defined the level of H4 acetylation within transcriptionally active and inactive regions of the genome. H4 within or adjacent to coding regions had a similar level of overall acetylation to input (bulk) chromatin and a similar pattern of acetylation of individual lysines (i.e. 16 > 8, 12 > 5). The acetylation of H4 in coding (and adjacent) regions was not correlated with transcriptional activity and did not vary with position along the constitutively active c-myc gene. Turnover of H4 acetates was not selectively increased in transcriptionally active chromatin. H4 associated with centric heterochromatin or with the CCCTAA repeat of telomeric heterochromatin was infrequently acetylated (< 1%) at all lysines. We conclude that nucleosomes containing acetylated H4 are scattered infrequently and possibly randomly through coding and adjacent regions and are essentially absent from heterochromatin. Induction of differentiation of HL-60 cells by exposure to dimethylsulfoxide or 12-o-tetradecanoylphorbol 13-acetate (TPA) did not alter the level of H4 acetylation within either the c-myc or c-fos genes or other coding regions, but did induce a transient increase in H4 acetylation within centric heterochromatin. Images

O'Neill, L P; Turner, B M

1995-01-01

104

Investigation of Nuclear Data Libraries with TRIPOLI-4 Monte Carlo Code for Sodium-cooled Fast Reactors  

NASA Astrophysics Data System (ADS)

The Sodium-cooled fast neutron reactor ASTRID is currently under design and development in France. Traditional ECCO/ERANOS fast reactor code system used for ASTRID core design calculations relies on multi-group JEFF-3.1.1 data library. To gauge the use of ENDF/B-VII.0 and JEFF-3.1.1 nuclear data libraries in the fast reactor applications, two recent OECD/NEA computational benchmarks specified by Argonne National Laboratory were calculated. Using the continuous-energy TRIPOLI-4 Monte Carlo transport code, both ABR-1000 MWth MOX core and metallic (U-Pu) core were investigated. Under two different fast neutron spectra and two data libraries, ENDF/B-VII.0 and JEFF-3.1.1, reactivity impact studies were performed. Using JEFF-3.1.1 library under the BOEC (Beginning of equilibrium cycle) condition, high reactivity effects of 808 ± 17 pcm and 1208 ± 17 pcm were observed for ABR-1000 MOX core and metallic core respectively. To analyze the causes of these differences in reactivity, several TRIPOLI-4 runs using mixed data libraries feature allow us to identify the nuclides and the nuclear data accounting for the major part of the observed reactivity discrepancies.

Lee, Y.-K.; Brun, E.

2014-04-01

105

Combining independent component analysis and Granger causality to investigate brain network dynamics with fNIRS measurements.  

PubMed

In this study a new strategy that combines Granger causality mapping (GCM) and independent component analysis (ICA) is proposed to reveal complex neural network dynamics underlying cognitive processes using functional near infrared spectroscopy (fNIRS) measurements. The GCM-ICA algorithm implements the following two procedures: (i) extraction of the region of interests (ROIs) of cortical activations by ICA, and (ii) estimation of the direct causal influences in local brain networks using Granger causality among voxels of ROIs. Our results show that the use of GCM in conjunction with ICA is able to effectively identify the directional brain network dynamics in time-frequency domain based on fNIRS recordings. PMID:24298421

Yuan, Zhen

2013-01-01

106

Manipulation of independent synthesis and degradation of polyphosphate in Escherichia coli for investigation of phosphate secretion from the cell.  

PubMed

The genes involved in polyphosphate metabolism in Escherichia coli were cloned behind different inducible promoters on separate plasmids. The gene coding for polyphosphate kinase (PPK), the enzyme responsible for polyphosphate synthesis, was placed behind the Ptac promoter. Polyphosphatase, a polyphosphate depolymerase, was similarly expressed by using the arabinose-inducible PBAD promoter. The ability of cells containing these constructs to produce active enzymes only when induced was confirmed by polyphosphate extraction, enzyme assays, and RNA analysis. The inducer concentrations giving optimal expression of each enzyme were determined. Experiments were performed in which ppk was induced early in growth, overproducing PPK and allowing large amounts of polyphosphate to accumulate (80 mumol in phosphate monomer units per g of dry cell weight). The ppx gene was subsequently induced, and polyphosphate was degraded to inorganic phosphate. Approximately half of this polyphosphate was depleted in 210 min. The phosphate released from polyphosphate allowed the growth of phosphate-starved cells and was secreted into the medium, leading to a down-regulation of the phosphate-starvation response. In addition, the steady-state polyphosphate level was precisely controlled by manipulating the degree of ppx induction. The polyphosphate content varied from 98 to 12 mumol in phosphate monomer units per g of dry cell weight as the arabinose concentration was increased from 0 to 0.02% by weight. PMID:9143103

Van Dien, S J; Keyhani, S; Yang, C; Keasling, J D

1997-05-01

107

Chromatographic separation and multicollection-ICPMS analysis of iron. Investigating mass-dependent and -independent isotope effects.  

PubMed

A procedure was developed that allows precise determination of Fe isotopic composition. Purification of Fe was achieved by ion chromatography on AG1-X8 strongly basic anion-exchange resin. No isotopic fractionation is associated with column chemistry within 0.02 per thousand /amu at 2sigma. The isotopic composition was measured with a Micromass IsoProbe multicollection inductively coupled plasma hexapole mass spectrometer. The Fe isotopic composition of the Orgueil CI1 carbonaceous chondrite, which best approximates the solar composition, is indistinguishable from that of IRMM-014 (-0.005 +/- 0.017 per thousand /amu). The IRMM-014 reference material is therefore used for normalization of the isotopic ratios. The protocol for analyzing mass-dependent variations is validated by measuring geostandards (IF-G, DTS-2, BCR-2, AGV-2) and heavily fractionated Fe left after vacuum evaporation of molten wüstite (FeO) and solar (MgO-Al(2)O(3)-SiO(2)-CaO-FeO in chondritic proportions) compositions. It is shown that the isotopic composition of Fe during evaporation of FeO follows a Rayleigh distillation with a fractionation factor alpha equal to (m(1)/m(2)()1/2), where m(1) and m(2) are the masses of the considered isotopes. This agrees with earlier measurements and theoretical expectations. The isotopic composition of Fe left after vacuum evaporation of solar composition also follows a Rayleigh distillation but with a fractionation factor (1.013 22 +/- 0.000 67 for the (56)Fe/(54)Fe ratio) that is lower than the square root of the masses (1.018 35). The protocol for analyzing mass-independent variations is validated by measuring terrestrial rocks that are not expected to show departure from mass-dependent fractionation. After internal normalization of the (57)Fe/(54)Fe ratio, the isotopic composition of Fe can be measured accurately with precisions of 0.2epsilon and 0.5epsilon at 2sigma for (56)Fe/(54)Fe and (58)Fe/(54)Fe ratios, respectively (epsilon refers to relative variations in parts per 10 000). For (58)Fe, this precision is an order of magnitude better than what had been achieved before. The method is applied to rocks that could potentially exhibit mass-independent effects, meteorites and Archaean terrestrial samples. The isotopic composition of a 3.8-Ga-old banded iron formation from Isua (IF-G, Greenland), and quartz-pyroxene rocks from Akilia and Innersuartuut (GR91-26 and SM/GR/171770, Greenland) are normal within uncertainties. Similarly, the Orgueil (CI1), Allende (CV3.2), Eagle Station (ESPAL), Brenham (MGPAL), and Old Woman (IIAB) meteorites do not show any mass-independent effect. PMID:15456307

Dauphas, Nicolas; Janney, Philip E; Mendybaev, Ruslan A; Wadhwa, Meenakshi; Richter, Frank M; Davis, Andrew M; van Zuilen, Mark; Hines, Rebekah; Foley, C Nicole

2004-10-01

108

Investigation of combined effects of independent variables on extraction of pectin from banana peel using response surface methodology  

Microsoft Academic Search

Combined effects of key factors (pH value, extraction temperature, extraction time, salting out time) on extraction of pectin from banana peel was investigated by response surface methodology (RSM). When enriched in pectin, this research can be useful for preparation of banana products. Results showed that extraction temperature and time had the most significant combined effect on the improvement of extraction

Li-ping Qiu; Guang-lei Zhao; Hui Wu; Lu Jiang; Xiao-feng Li; Jun-juan Liu

2010-01-01

109

A novel bandwidth efficient coding scheme employing turbo codes  

Microsoft Academic Search

We have investigated a novel bandwidth efficient channel coding scheme that has a code structure similar to binary turbo codes but employs Ungerboeck codes as component codes. The combination of turbo codes with powerful bandwidth efficient component codes leads to a straightforward encoder structure and allows iterative decoding in analogy to the binary turbo decoder. However, certain special conditions need

Patrick Robertson; Thomas Worz

1996-01-01

110

Independent Technical Investigation of the Puna Geothermal Venture Unplanned Steam Release, June 12 and 13, 1991, Puna, Hawaii  

SciTech Connect

On June 24, 1991, a third-party investigation team consisting of Richard P. Thomas, Duey E. Milner, James L. Moore, and Dick Whiting began an investigation into the blowout of well KS-8, which occurred at the Puna Geothermal Venture (PGV) site on June 12, 1991, and caused the unabated release of steam for a period of 31 hours before PGV succeeded in closing in the well. The scope of the investigation was to: (a) determine the cause(s) of the incident; (b) evaluate the adequacy of PGVs drilling and blowout prevention equipment and procedures; and (c) make recommendations for any appropriate changes in equipment and/or procedures. This report finds that the blowout occurred because of inadequacies in PGVs drilling plan and procedures and not as a result of unusual or unmanageable subsurface geologic or hydrologic conditions. While the geothermal resource in the area being drilled is relatively hot, the temperatures are not excessive for modem technology and methods to control. Fluid pressures encountered are also manageable if proper procedures are followed and the appropriate equipment is utilized. A previous blowout of short duration occurred on February 21, 1991, at the KS-7 injection well being drilled by PGV at a depth of approximately 1600'. This unexpected incident alerted PGV to the possibility of encountering a high temperature, fractured zone at a relatively shallow depth. The experience at KS-7 prompted PGV to refine its hydrological model; however, the drilling plan utilized for KS-8 was not changed. Not only did PGV fail to modify its drilling program following the KS-7 blowout, but they also failed to heed numerous ''red flags'' (warning signals) in the five days preceding the KS-8 blowout, which included a continuous 1-inch flow of drilling mud out of the wellbore, gains in mud volume while pulling stands, and gas entries while circulating muds bottoms up, in addition to lost circulation that had occurred earlier below the shoe of the 13-3/8-hch casing.

Thomas, Richard; Whiting, Dick; Moore, James; Milner, Duey

1991-07-01

111

CYP2B6 Non-Coding Variation Associated with Smoking Cessation Is Also Associated with Differences in Allelic Expression, Splicing, and Nicotine Metabolism Independent of Common Amino-Acid Changes  

PubMed Central

The Cytochrome P450 2B6 (CYP2B6) enzyme makes a small contribution to hepatic nicotine metabolism relative to CYP2A6, but CYP2B6 is the primary enzyme responsible for metabolism of the smoking cessation drug bupropion. Using CYP2A6 genotype as a covariate, we find that a non-coding polymorphism in CYP2B6 previously associated with smoking cessation (rs8109525) is also significantly associated with nicotine metabolism. The association is independent of the well-studied non-synonymous variants rs3211371, rs3745274, and rs2279343 (CYP2B6*5 and *6). Expression studies demonstrate that rs8109525 is also associated with differences in CYP2B6 mRNA expression in liver biopsy samples. Splicing assays demonstrate that specific splice forms of CYP2B6 are associated with haplotypes defined by variants including rs3745274 and rs8109525. These results indicate differences in mRNA expression and splicing as potential molecular mechanisms by which non-coding variation in CYP2B6 may affect enzymatic activity leading to differences in metabolism and smoking cessation.

Bloom, A. Joseph; Martinez, Maribel; Chen, Li-Shiun; Bierut, Laura J.; Murphy, Sharon E.; Goate, Alison

2013-01-01

112

Independence Is.  

ERIC Educational Resources Information Center

This workbook is designed to help participants of the Independence Training Program (ITP) to achieve a definition of "independence." The program was developed for teenage girls. The process for developing the concept of independence consists of four steps. Step one instructs the participant to create an imaginary situation where she is completely…

Stickney, Sharon

113

Evaluation of the rodent Hershberger bioassay on intact juvenile males--testing of coded chemicals and supplementary biochemical investigations.  

PubMed

Under the auspices of the Organization for Economic Cooperation and Development (OECD) the Hershberger assay on juvenile intact male rats is being validated as a screen for compounds with anti-androgenic potential. We participated in the testing of coded chemicals. Compounds included the positive control flutamide (FLUT, 3 mg/kg), linuron (LIN, 10, 100 mg/kg), p,p'-DDE (16, 160 mg/kg), and two negative substances, 4-nonylphenol (NP, 160 mg/kg) and 2,4-dinitrophenol (DNP, 10 mg/kg). Compounds were administered for 10 consecutive days by gavage to testosterone propionate (TP, 1 mg/kgs.c.)-supplemented rats. Uncoding revealed these results: compared to vehicle controls, treatment with TP resulted in increased androgen-sensitive tissue (AST) weights of ventral prostate (VP), seminal vesicles (SV), levator ani and bulbocavernosus muscles (LABC), Cowper's glands, and epididymides, and in decreased testes weight. When assessing anti-androgenic potential in TP-supplemented rats, FLUT decreased all AST weights, and increased testes weight. p,p'-DDE at the high dose, decreased final body weight and all AST weights, whereas the low dose only affected SV weight. LIN slightly decreased final body weight and decreased absolute SV and LABC and relative SV weights only at the high dose. NP decreased final body weight and only absolute SV weights, DNP was ineffective. Investigations not requested by OECD included measurement of liver enzymes and revealed strong induction of testosterone-metabolizing and phase II conjugating enzymes by p,p'-DDE. Our findings suggest that in principle the juvenile intact male rat can be used in the Hershberger assay to screen for anti-androgenic potential thereby contributing to a refinement of the assay in terms of animal welfare. However, in our hands this animal model was somewhat less sensitive than the peripubertal castrated rat. Final conclusions, however, can only be drawn on the basis of all available validation data. Results obtained with the negative reference compound NP suggest that a treatment-related decrement in body weights may affect AST weights and represent a confounding factor when screening for anti-androgenic properties. Finally, p,p'-DDE may affect AST weights by several mechanisms including enhanced testosterone metabolism. PMID:19467291

Freyberger, A; Schladt, L

2009-08-01

114

Supporting the cybercrime investigation process: Effective discrimination of source code authors based on byte-level information  

Microsoft Academic Search

Source code authorship analysis is the particular field that attempts to identify the author of a computer program by treating each program as a linguistically analyzable entity. This is usually based on other undisputed program samples from the same author. There are several cases where the application of such a method could be of a major benefit, such as tracing

Georgia Frantzeskou; Efstathios Stamatatos; Stefanos Gritzalis

2005-01-01

115

Investigations on boron carbide oxidation for nuclear reactors safety—General modelling for ICARE\\/CATHARE code applications  

Microsoft Academic Search

The present paper deals with the problem of boron carbide pellet oxidation which might occur during a severe accident. A basic correlation, involving global variables, has been developed for the simulation of boron carbide oxidation with the ICARE\\/CATHARE code. This modelling has been based on available experimental data, including the VERDI separate effects experiments performed by IRSN at low pressures

N. Seiler; F. Bertrand; O. Marchand; G. Repetto; S. Ederli

2008-01-01

116

On Symmetrical Multilevel Diversity Coding  

Microsoft Academic Search

Symmetrical multilevel diversity coding with independent data streams has been studied by Roche et al. (1992), and the admissible coding rate region was determined for the case of three levels. In particular, it was shown that coding by superposition is optimal, which means that optimality can be achieved by very simple coding. However, it is very difficult to generalize their

Raymond W. Yeung; Zhen Zhang

1999-01-01

117

Speech coding  

SciTech Connect

Speech is the predominant means of communication between human beings and since the invention of the telephone by Alexander Graham Bell in 1876, speech services have remained to be the core service in almost all telecommunication systems. Original analog methods of telephony had the disadvantage of speech signal getting corrupted by noise, cross-talk and distortion Long haul transmissions which use repeaters to compensate for the loss in signal strength on transmission links also increase the associated noise and distortion. On the other hand digital transmission is relatively immune to noise, cross-talk and distortion primarily because of the capability to faithfully regenerate digital signal at each repeater purely based on a binary decision. Hence end-to-end performance of the digital link essentially becomes independent of the length and operating frequency bands of the link Hence from a transmission point of view digital transmission has been the preferred approach due to its higher immunity to noise. The need to carry digital speech became extremely important from a service provision point of view as well. Modem requirements have introduced the need for robust, flexible and secure services that can carry a multitude of signal types (such as voice, data and video) without a fundamental change in infrastructure. Such a requirement could not have been easily met without the advent of digital transmission systems, thereby requiring speech to be coded digitally. The term Speech Coding is often referred to techniques that represent or code speech signals either directly as a waveform or as a set of parameters by analyzing the speech signal. In either case, the codes are transmitted to the distant end where speech is reconstructed or synthesized using the received set of codes. A more generic term that is applicable to these techniques that is often interchangeably used with speech coding is the term voice coding. This term is more generic in the sense that the coding techniques are equally applicable to any voice signal whether or not it carries any intelligible information, as the term speech implies. Other terms that are commonly used are speech compression and voice compression since the fundamental idea behind speech coding is to reduce (compress) the transmission rate (or equivalently the bandwidth) And/or reduce storage requirements In this document the terms speech and voice shall be used interchangeably.

Ravishankar, C., Hughes Network Systems, Germantown, MD

1998-05-08

118

Randomized Distributed Network Coding.  

National Technical Information Service (NTIS)

A network and a method for transmitting processes in a network are disclosed, where a randomized coding approach is provided. Network nodes transmit on each outgoing link a linear combination of incoming signals, specified by independently and randomly ch...

D. Karger M. Effros M. Medard R. Koetter T. Ho

2004-01-01

119

The effects of left or right hemispheric epilepsy on language networks investigated with semantic decision fMRI task and independent component analysis  

PubMed Central

Chronic and progressive brain injury, as seen in epilepsy, may alter brain networks that underlie cognitive functions. To evaluate the effect of epilepsy on language functions we investigated the neuroanatomical basis of semantic processing in patients with left (LHE) or right (RHE) hemispheric onset epilepsy using semantic decision fMRI paradigm and group independent component analysis (ICA); we then compared the results of our investigations to language network in healthy subjects examined with the same language task (1). Group ICA is a data-driven technique capable of revealing the functional organization of the human brain based on fMRI data. In addition to providing functional connectivity information, ICA can also provide information about the temporal dynamics of underlying networks subserving specific cognitive functions. In this study, we implemented two complementary analyses to investigate group differences in underlying network dynamics based on associated independent component (IC) time courses (a priori defined criterion or a posteriori identified maximum likelihood descriptor). We detected several differences between healthy controls and patients with epilepsy not previously observed with standard fMRI analysis methods. Our analyses confirmed the presence of different effects of LHE or RHE on the behavior of the language network. In particular, a major difference was noted in the nodes subserving verbal encoding and retrieval in the bilateral medial temporal regions; these effects were dependent on the side of the epilepsy onset i.e., effects were different with left or right hemispheric epilepsy. These findings may explain the differences in verbal and non-verbal memory abilities between the left and right hemispheric epilepsy patients. Further, while the effects on other nodes of the network were more subtle, several deviations from normal network function were observed in patients with LHE (e.g., alterations in the functions of the primarily left fronto-temporal network module) or in patients with RHE (e.g., differences in the medial retrosplenial module responsible for mental imagery or in the anterior cingulate module subserving attention control). These findings highlight the negative effects of epilepsy not only on the main left hemispheric language network nodes in patients with LHE but also document the effects of epilepsy on other language network nodes whether exerted by LHE or RHE. Further, these results document the advantages of using group ICA for investigating the effects of disease state (e.g., epilepsy) on the network subserving cognitive processing and provide an interesting avenue for further exploration.

Karunanayaka, Prasanna; Kim, Kwang Ki; Holland, Scott K.; Szaflarski, Jerzy P.

2011-01-01

120

Transionospheric Propagation Code (TIPC)  

Microsoft Academic Search

The Transionospheric Propagation Code is a computer program developed at Los Alamos National Lab to perform certain tasks related to the detection of VHF signals following propagation through the ionosphere. The code is written in FORTRAN 77, runs interactively and was designed to be as machine independent as possible. A menu format in which the user is prompted to supply

Robert Roussel-Dupre; Thomas A. Kelley

1990-01-01

121

Runlength codes from source codes  

Microsoft Academic Search

A class of binary runlength codes, also known as (d,k) codes, is analyzed. These codes are developed by constructing a lossless source code that maps runlengths into unconstrained binary sequences. The source code is constructed for the maxentropic distribution on runlengths. The inverse of the source code, which outputs runlengths guided toward the ideal maxentropic distribution, is the (d,k) code.

Kenneth J. Kerpez

1991-01-01

122

Independent Safety Organization.  

National Technical Information Service (NTIS)

Brookhaven National Laboratory has conducted a study on the need and feasibility of an independent organization to investigate significant safety events for the Office for Analysis and Evaluation of Operational Data, USNRC. The study consists of three par...

W. Y. Kato E. V. Weinstock J. F. Carew R. J. Cerbone J. G. Guppy

1985-01-01

123

Hermitian Codes as Generalized Reed-Solomon Codes  

Microsoft Academic Search

Hermitian codes obtained from Hermitian curves are shown to be concatenated generalized Reed-Solomon codes. This interpretation of Hermitian codes is used to investigate their structure. An efficient encoding algorithm is given for Hermitian codes. A new general decoding algorithm is given and applied to Hermitian codes to give a decoding algorithm capable of decoding up to the full error correcting

Tomik Yaghoobian; Ian F. Blake

1992-01-01

124

Combined Fountain Code with Network Coding in Cooperative Communication  

Microsoft Academic Search

In this paper, we will investigate the block error rate (BLER) performance in cooperative communication, through combining fountain code with network coding. Contrast to the fixed-rate code, the rate of fountain code is not determined in advance, since that varies according to the instant channel state information. Under the error-free channel condition, network coding can get the maximum possible rate

Jing Yang; Jianping An; Xiangming Li; Lei Yuan

2010-01-01

125

MORSE Monte Carlo code  

SciTech Connect

The MORSE code is a large general-use multigroup Monte Carlo code system. Although no claims can be made regarding its superiority in either theoretical details or Monte Carlo techniques, MORSE has been, since its inception at ORNL in the late 1960s, the most widely used Monte Carlo radiation transport code. The principal reason for this popularity is that MORSE is relatively easy to use, independent of any installation or distribution center, and it can be easily customized to fit almost any specific need. Features of the MORSE code are described.

Cramer, S.N.

1984-01-01

126

Tokamak Systems Code  

SciTech Connect

The FEDC Tokamak Systems Code calculates tokamak performance, cost, and configuration as a function of plasma engineering parameters. This version of the code models experimental tokamaks. It does not currently consider tokamak configurations that generate electrical power or incorporate breeding blankets. The code has a modular (or subroutine) structure to allow independent modeling for each major tokamak component or system. A primary benefit of modularization is that a component module may be updated without disturbing the remainder of the systems code as long as the imput to or output from the module remains unchanged.

Reid, R.L.; Barrett, R.J.; Brown, T.G.; Gorker, G.E.; Hooper, R.J.; Kalsi, S.S.; Metzler, D.H.; Peng, Y.K.M.; Roth, K.E.; Spampinato, P.T.

1985-03-01

127

Residential wire codes: reproducibility and relation with measured magnetic fields  

PubMed Central

OBJECTIVES: To investigate the reproducibility of wire codes to characterise residential power line configurations and to determine the extent to which wire codes provide a proxy measure of residential magnetic field strength in a case-control study of childhood leukaemia conducted in nine states within the United States. METHODS: Misclassification of wire codes was assessed with independent measurements by two technicians for 187 residences. The association between categories of wire code and measured level of magnetic field was evaluated in 858 residences with both a wire code measurement and a 24 hour measurement of the magnetic field in the bedroom. The strength of the association between category of wire code and risk of leukaemia was examined in two regions with different average levels of magnetic field in homes with high categories of wire code. RESULTS: The reproducibility of any of three different classifications of wire codes was excellent (kappa > or = 0.89). Mean and median magnetic fields, and the percentage of homes with high magnetic fields increased with increasing category for each of the wire code classification schemes. The size of the odds ratios for risk of leukaemia and high categories of wire code did not reflect the mean levels of the magnetic field in those categories in two study regions. CONCLUSION: Misclassification of categories of wire code is not a major source of bias in the study. Wire codes provide a proxy measure of exposure to residential magnetic fields. If magnetic fields were a risk factor for leukaemia, however, there would be some attenuation of risk estimates based on wire codes because of misclassification of exposure to magnetic fields at both extremes of the wire code range. The lack of an association between high categories of wire code and risk of leukaemia cannot be explained by a failure of the wire code classification schemes to estimate exposure to magnetic fields in the study area.  

Tarone, R. E.; Kaune, W. T.; Linet, M. S.; Hatch, E. E.; Kleinerman, R. A.; Robison, L. L.; Boice, J. D.; Wacholder, S.

1998-01-01

128

Code Motion and Code Placement: Just Synonyms?  

Microsoft Academic Search

We prove that there is no difference between code motion (CM ) and code placement (CP) in the traditional syntactic setting, however, a dramatic difference in thesemantic setting. We demonstrate this by re-investigating semantic CM under theperspective of the recent development of syntactic CM. Besides clarifying and highlighteningthe analogies and essential differences between the syntactic and the semanticapproach, this leads

Jens Knoop; Oliver Riithing; Bernhard Steffen

1998-01-01

129

Application of a multi-block CFD code to investigate the impact of geometry modeling on centrifugal compressor flow field predictions  

SciTech Connect

CFD codes capable of utilizing multi-block grids provide the capability to analyze the complete geometry of centrifugal compressors. Attendant with this increased capability is potentially increased grid setup time and more computational overhead with the resultant increase in wall clock time to obtain a solution. If the increase in difficulty of obtaining a solution significantly improves the solution from that obtained by modeling the features of the tip clearance flow or the typical bluntness of a centrifugal compressor`s trailing edge, then the additional burden is worthwhile. However, if the additional information obtained is of marginal use, then modeling of certain features of the geometry may provide reasonable solutions for designers to make comparative choices when pursuing a new design. In this spirit a sequence of grids were generated to study the relative importance of modeling versus detailed gridding of the tip gap and blunt trailing edge regions of the NASA large low-speed centrifugal compressor for which there is considerable detailed internal laser anemometry data available for comparison. The results indicate: (1) There is no significant difference in predicted tip clearance mass flow rate whether the tip gap is gridded or modeled. (2) Gridding rather than modeling the trailing edge results in better predictions of some flow details downstream of the impeller, but otherwise appears to offer no great benefits. (3) The pitchwise variation of absolute flow angle decreases rapidly up to 8% impeller radius ratio and much more slowly thereafter. Although some improvements in prediction of flow field details are realized as a result of analyzing the actual geometry there is no clear consensus that any of the grids investigated produced superior results in every case when compared to the measurements. However, if a multi-block code is available, it should be used, as it has the propensity for enabling better predictions than a single block code.

Hathaway, M.D. [Vehicle Technology Center, Cleveland, OH (United States); Wood, J.R. [NASA Lewis Research Center, Cleveland, OH (United States)

1997-10-01

130

Developing Research Skills: Independent Research Projects on Animals and Plants for Building the Research Skills of Report Writing, Mind Mapping, and Investigating through Inquiries. Revised Edition.  

ERIC Educational Resources Information Center

This book presents a collection of motivating, independent activities that involve animals and plants for use in developing the research skills of students in grades 2-6. Projects included in the book cover various levels of difficulty and are designed to promote higher-level thinking skills. Research components included in the activities in the…

Banks, Janet Caudill

131

'Independence' Panorama  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site] Click on the image for 'Independence' Panorama (QTVR)

This is the Spirit 'Independence' panorama, acquired on martian days, or sols, 536 to 543 (July 6 to 13, 2005), from a position in the 'Columbia Hills' near the summit of 'Husband Hill.' The summit of 'Husband Hill' is the peak near the right side of this panorama and is about 100 meters (328 feet) away from the rover and about 30 meters (98 feet) higher in elevation. The rocky outcrops downhill and on the left side of this mosaic include 'Larry's Lookout' and 'Cumberland Ridge,' which Spirit explored in April, May, and June of 2005.

The panorama spans 360 degrees and consists of 108 individual images, each acquired with five filters of the rover's panoramic camera. The approximate true color of the mosaic was generated using the camera's 750-, 530-, and 480-nanometer filters. During the 8 martian days, or sols, that it took to acquire this image, the lighting varied considerably, partly because of imaging at different times of sol, and partly because of small sol-to-sol variations in the dustiness of the atmosphere. These slight changes produced some image seams and rock shadows. These seams have been eliminated from the sky portion of the mosaic to better simulate the vista a person standing on Mars would see. However, it is often not possible or practical to smooth out such seams for regions of rock, soil, rover tracks or solar panels. Such is the nature of acquiring and assembling large panoramas from the rovers.

2005-01-01

132

Coding for reliable satellite communications  

NASA Technical Reports Server (NTRS)

Several error control coding techniques for reliable satellite communications were investigated to find algorithms for fast decoding of Reed-Solomon codes in terms of dual basis. The decoding of the (255,223) Reed-Solomon code, which is used as the outer code in the concatenated TDRSS decoder, was of particular concern.

Lin, S.

1984-01-01

133

CIGALE: Code Investigating GALaxy Emission  

NASA Astrophysics Data System (ADS)

We present CIGALE (Burgarella et al. 2005; Noll et al. 2009), a software developed at the Laboratoire d'Astrophysique de Marseille to fit galaxy spectral energy distributions from the rest-frame far-UV to far-IR wavelength range, and to derive some of their physical parameters. We also give some examples of scientific results obtained with CIGALE.

Roehlly, Y.; Burgarella, D.; Buat, V.; Giovannoli, É.; Noll, S.; Serra, P.

2012-09-01

134

Permutation codes for sources.  

NASA Technical Reports Server (NTRS)

Source encoding techniques based on permutation codes are investigated. For a broad class of distortion measures it is shown that optimum encoding of a source permutation code is easy to instrument even for very long block lengths. Also, the nonparametric nature of permutation encoding is well suited to situations involving unknown source statistics. For the squared-error distortion measure a procedure for generating good permutation codes of a given rate and block length is described. The performance of such codes for a memoryless Gaussian source is compared both with the rate-distortion function bound and with the performance of various quantization schemes. The comparison reveals that permutation codes are asymptotically ideal for small rates and perform as well as the best entropy-coded quantizers presently known for intermediate rates. They can be made to compare favorably at high rates, too, provided the coding delay associated with extremely long block lengths is tolerable.

Berger, T.; Jelinek, F.; Wolf, J. K.

1972-01-01

135

Synthesizing Certified Code  

NASA Technical Reports Server (NTRS)

Code certification is a lightweight approach to demonstrate software quality on a formal level. Its basic idea is to require producers to provide formal proofs that their code satisfies certain quality properties. These proofs serve as certificates which can be checked independently. Since code certification uses the same underlying technology as program verification, it also requires many detailed annotations (e.g., loop invariants) to make the proofs possible. However, manually adding theses annotations to the code is time-consuming and error-prone. We address this problem by combining code certification with automatic program synthesis. We propose an approach to generate simultaneously, from a high-level specification, code and all annotations required to certify generated code. Here, we describe a certification extension of AUTOBAYES, a synthesis tool which automatically generates complex data analysis programs from compact specifications. AUTOBAYES contains sufficient high-level domain knowledge to generate detailed annotations. This allows us to use a general-purpose verification condition generator to produce a set of proof obligations in first-order logic. The obligations are then discharged using the automated theorem E-SETHEO. We demonstrate our approach by certifying operator safety for a generated iterative data classification program without manual annotation of the code.

Whalen, Michael; Schumann, Johann; Fischer, Bernd

2002-01-01

136

22 CFR 228.03 - Identification of the authorized principal geographic procurement codes.  

Code of Federal Regulations, 2013 CFR

...purposes of procurements under the Support for Economic and Democratic Development of the Independent States of the Former Soviet Union, 22 U.S.C. 2295b, the authorized principal geographic codes are Code 937 and Code 110 (New Independent...

2013-04-01

137

Code Status  

MedlinePLUS

... Home Clinical Critical Care Information for Patients | | More Code Status Information for Patients Introduction General Information Common ... Approaches in Critical Care Commonly Asked Questions Credits "Code status" are the words used by hospital staff ...

138

Code Stabilization  

Microsoft Academic Search

Dijkstra's concept of self-stabilization assumes that faults can only a! ect the variables of a program. We study the notion of self-stabilization if faults can also a! ect (i.e., augment) the program code of a system. A code stabilizing sys- tem automatically recovers from (almost) arbitrary perturbations of its program code. We prove some lower bounds for code stabilizing systems

Felix C. Freiling; Sukumar Ghosh

2005-01-01

139

Comet assay in reconstructed 3D human epidermal skin models--investigation of intra- and inter-laboratory reproducibility with coded chemicals  

PubMed Central

Reconstructed 3D human epidermal skin models are being used increasingly for safety testing of chemicals. Based on EpiDerm™ tissues, an assay was developed in which the tissues were topically exposed to test chemicals for 3h followed by cell isolation and assessment of DNA damage using the comet assay. Inter-laboratory reproducibility of the 3D skin comet assay was initially demonstrated using two model genotoxic carcinogens, methyl methane sulfonate (MMS) and 4-nitroquinoline-n-oxide, and the results showed good concordance among three different laboratories and with in vivo data. In Phase 2 of the project, intra- and inter-laboratory reproducibility was investigated with five coded compounds with different genotoxicity liability tested at three different laboratories. For the genotoxic carcinogens MMS and N-ethyl-N-nitrosourea, all laboratories reported a dose-related and statistically significant increase (P < 0.05) in DNA damage in every experiment. For the genotoxic carcinogen, 2,4-diaminotoluene, the overall result from all laboratories showed a smaller, but significant genotoxic response (P < 0.05). For cyclohexanone (CHN) (non-genotoxic in vitro and in vivo, and non-carcinogenic), an increase compared to the solvent control acetone was observed only in one laboratory. However, the response was not dose related and CHN was judged negative overall, as was p-nitrophenol (p-NP) (genotoxic in vitro but not in vivo and non-carcinogenic), which was the only compound showing clear cytotoxic effects. For p-NP, significant DNA damage generally occurred only at doses that were substantially cytotoxic (>30% cell loss), and the overall response was comparable in all laboratories despite some differences in doses tested. The results of the collaborative study for the coded compounds were generally reproducible among the laboratories involved and intra-laboratory reproducibility was also good. These data indicate that the comet assay in EpiDerm™ skin models is a promising model for the safety assessment of compounds with a dermal route of exposure.

Pfuhler, Stefan

2013-01-01

140

Material-dependent and material-independent selection processes in the frontal and parietal lobes: an event-related fMRI investigation of response competition  

NASA Technical Reports Server (NTRS)

The present study used the flanker task [Percept. Psychophys. 16 (1974) 143] to identify neural structures that support response selection processes, and to determine which of these structures respond differently depending on the type of stimulus material associated with the response. Participants performed two versions of the flanker task while undergoing event-related functional magnetic resonance imaging (fMRI). Both versions of the task required participants to respond to a central stimulus regardless of the responses associated with simultaneously presented flanking stimuli, but one used colored circle stimuli and the other used letter stimuli. Competition-related activation was identified by comparing Incongruent trials, in which the flanker stimuli indicated a different response than the central stimulus, to Neutral stimuli, in which the flanker stimuli indicated no response. A region within the right inferior frontal gyrus exhibited significantly more competition-related activation for the color stimuli, whereas regions within the middle frontal gyri of both hemispheres exhibited more competition-related activation for the letter stimuli. The border of the right middle frontal and inferior frontal gyri and the anterior cingulate cortex (ACC) were significantly activated by competition for both types of stimulus materials. Posterior foci demonstrated a similar pattern: left inferior parietal cortex showed greater competition-related activation for the letters, whereas right parietal cortex was significantly activated by competition for both materials. These findings indicate that the resolution of response competition invokes both material-dependent and material-independent processes.

Hazeltine, Eliot; Bunge, Silvia A.; Scanlon, Michael D.; Gabrieli, John D E.

2003-01-01

141

Is ADHD a Risk Factor Independent of Conduct Disorder for Illicit Substance Use? A Meta-Analysis and Meta-Regression Investigation  

ERIC Educational Resources Information Center

Objective: To investigate meta-analytically if the association between ADHD and illicit substance use (ISU) is maintained when controlling for conduct disorder/oppositional-defiant disorder (CD/ODD). Method: A systematic literature review was conducted through Medline from 1980 to 2008. Data extracted and selections made by one author were…

Serra-Pinheiro, Maria Antonia; Coutinho, Evandro S. F.; Souza, Isabella S.; Pinna, Camilla; Fortes, Didia; Araujo, Catia; Szobot, Claudia M.; Rohde, Luis A.; Mattos, Paulo

2013-01-01

142

Extension of the supercritical carbon dioxide brayton cycle to low reactor power operation: investigations using the coupled anl plant dynamics code-SAS4A/SASSYS-1 liquid metal reactor code system.  

SciTech Connect

Significant progress has been made on the development of a control strategy for the supercritical carbon dioxide (S-CO{sub 2}) Brayton cycle enabling removal of power from an autonomous load following Sodium-Cooled Fast Reactor (SFR) down to decay heat levels such that the S-CO{sub 2} cycle can be used to cool the reactor until decay heat can be removed by the normal shutdown heat removal system or a passive decay heat removal system such as Direct Reactor Auxiliary Cooling System (DRACS) loops with DRACS in-vessel heat exchangers. This capability of the new control strategy eliminates the need for use of a separate shutdown heat removal system which might also use supercritical CO{sub 2}. It has been found that this capability can be achieved by introducing a new control mechanism involving shaft speed control for the common shaft joining the turbine and two compressors following reduction of the load demand from the electrical grid to zero. Following disconnection of the generator from the electrical grid, heat is removed from the intermediate sodium circuit through the sodium-to-CO{sub 2} heat exchanger, the turbine solely drives the two compressors, and heat is rejected from the cycle through the CO{sub 2}-to-water cooler. To investigate the effectiveness of shaft speed control, calculations are carried out using the coupled Plant Dynamics Code-SAS4A/SASSYS-1 code for a linear load reduction transient for a 1000 MWt metallic-fueled SFR with autonomous load following. No deliberate motion of control rods or adjustment of sodium pump speeds is assumed to take place. It is assumed that the S-CO{sub 2} turbomachinery shaft speed linearly decreases from 100 to 20% nominal following reduction of grid load to zero. The reactor power is calculated to autonomously decrease down to 3% nominal providing a lengthy window in time for the switchover to the normal shutdown heat removal system or for a passive decay heat removal system to become effective. However, the calculations reveal that the compressor conditions are calculated to approach surge such that the need for a surge control system for each compressor is identified. Thus, it is demonstrated that the S-CO{sub 2} cycle can operate in the initial decay heat removal mode even with autonomous reactor control. Because external power is not needed to drive the compressors, the results show that the S-CO{sub 2} cycle can be used for initial decay heat removal for a lengthy interval in time in the absence of any off-site electrical power. The turbine provides sufficient power to drive the compressors. Combined with autonomous reactor control, this represents a significant safety advantage of the S-CO{sub 2} cycle by maintaining removal of the reactor power until the core decay heat falls to levels well below those for which the passive decay heat removal system is designed. The new control strategy is an alternative to a split-shaft layout involving separate power and compressor turbines which had previously been identified as a promising approach enabling heat removal from a SFR at low power levels. The current results indicate that the split-shaft configuration does not provide any significant benefits for the S-CO{sub 2} cycle over the current single-shaft layout with shaft speed control. It has been demonstrated that when connected to the grid the single-shaft cycle can effectively follow the load over the entire range. No compressor speed variation is needed while power is delivered to the grid. When the system is disconnected from the grid, the shaft speed can be changed as effectively as it would be with the split-shaft arrangement. In the split-shaft configuration, zero generator power means disconnection of the power turbine, such that the resulting system will be almost identical to the single-shaft arrangement. Without this advantage of the split-shaft configuration, the economic benefits of the single-shaft arrangement, provided by just one turbine and lower losses at the design point, are more important to the overall cycle performance. Therefore, the single-shaft

Moisseytsev, A.; Sienicki, J. J. (Nuclear Engineering Division)

2012-05-10

143

Suboptimum decoding of block codes  

NASA Technical Reports Server (NTRS)

This paper investigates a class of decomposable codes, their distance and structural properties. it is shown that this class includes several classes of well known and efficient codes as subclasses. Several methods for constructing decomposable codes or decomposing codes are presented. A two-stage soft decision decoding scheme for decomposable codes, their translates or unions of translates is devised. This two-stage soft-decision decoding is suboptimum, and provides an excellent trade-off between the error performance and decoding complexity for codes of moderate and long block length.

Lin, Shu; Kasami, Tadao

1991-01-01

144

Improvement in elastographic signal-to-noise ratio and resolution using coded excitation in elastography  

Microsoft Academic Search

Coded excitation has been used in conventional sonography to improve the sonographic signal-to-noise ratio independently of resolution. In elastography, a tradeoff exists between spatial resolution and the elastographic signal-to-noise ratio (SNRe). In the present work, the use of coded excitation was investigated to remove this ambiguity in elastography. Both numerical simulations and phantom experiments were carried out to estimate the

Remi Souchon; Jean-Christophe Bera; Agnes Pousse; Jean-Yves Chapelon

2001-01-01

145

Computer Code  

NASA Technical Reports Server (NTRS)

COSMIC MINIVER, a computer code developed by NASA for analyzing aerodynamic heating and heat transfer on the Space Shuttle, has been used by Marquardt Company to analyze heat transfer on Navy/Air Force missile bodies. The code analyzes heat transfer by four different methods which can be compared for accuracy. MINIVER saved Marquardt three months in computer time and $15,000.

1985-01-01

146

Nested codes for secure transmission  

Microsoft Academic Search

Abstract—This paper investigates the problem of ensuring secure communication through error-correcting coding methods. A practical structured secure coding design is considered for a general wiretap channel, in which the main channel and the eavesdropper channel are binary-input symmetric-output memoryless (BISOM) channels. The proposed secure error- correcting code has a nested code structure. The nesting is based on cosets of a

Ruoheng Liu; H. Vincent Poor; Predrag Spasojevic; Yingbin Liang

2008-01-01

147

Behavioral correlates for the Minnesota Multiphasic Personality Inventory 4-9, 9-4 code types: A case of the emperor's new clothes?  

Microsoft Academic Search

Attempted to demonstrate behavioral correlates of 2 related MMPI code types (4-9, 9-4) with 2 large independent samples of inpatients from state psychiatric facilities (N = 2,869). Sample size permitted subanalyses of the effects of sex, race, and separate code type on results. While earlier investigations have typically found that this code type is given by sociopaths who are irritable,

Malcolm D. Gynther; Harold Altman; Robert W. Warbin

1973-01-01

148

Development and Application of a Two-Dimensional Computer Code for the Investigation of the Transient Behaviour of a Steam Reformer with Segmental Baffles.  

National Technical Information Service (NTIS)

This study deals with the theoretical description of heat transport and flow distribution in a helium-heated steam reformer with segmental baffles. For this purpose a two-dimensional, transient computer code is developed, which is described in detail. A f...

H. Brab

1987-01-01

149

Error Correction Coding With LDPC Codes for Patterned Media Storage  

Microsoft Academic Search

Recently, the ldquomultiple islands per read headrdquo model has been proposed for patterned media storage systems. In this paper, we investigated the applications of nonbinary low-density parity-check (LDPC) codes to such channels. Different nonbinary LDPC codes are designed for different read head models. We have also investigated the iterative decoding\\/detection algorithms for such coded systems. Simulation results show that significant

Xingcheng Liu; Chunhua Shi; Man Teng; Xiao Ma

2009-01-01

150

Profile Guided Code Positioning  

Microsoft Academic Search

This paper presents the results of our investigation of code positioning techniques using execution profile data as input into the compilation process. The primary objective of the positioning is to reduce the overhead of the instruction memory hierarchy. After initial investigation in the literature, we decided to implement two prototypes for the Hewlett-Packard Precision Architecture (PA-RISC). The first, built on

Karl Pettis; Robert C. Hansen

1990-01-01

151

Getting Students to be Successful, Independent Investigators  

ERIC Educational Resources Information Center

Middle school students often struggle when writing testable problems, planning valid and reliable procedures, and drawing meaningful evidence-based conclusions. To address this issue, the author created a student-centered lab handout to facilitate the inquiry process for students. This handout has reduced students' frustration and helped them…

Thomas, Jeffrey D.

2010-01-01

152

Digital holographic interferometry compared to a 3D Euler code in investigating the supersonic flow around an axisymmetric re-entry model  

NASA Astrophysics Data System (ADS)

The flow field around an axi-symmetric blunt nose cylinder-flare model has been studied experimentally using a holographic interferometry system with digital image post-processing. The model was placed in a supersonic flow field at a Mach number of 2.95 and at angles of incidence between 0 degree(s) and 20 degree(s). The results have been compared to inviscid flow calculations with a 3D Euler code.

Timmerman, Brenda H.; Lanen, Theo A.

1993-12-01

153

Quality assurance and verification of the MACCS (MELCOR Accident Consequence Code System) code, Version 1. 5  

Microsoft Academic Search

An independent quality assurance (QA) and verification of Version 1.5 of the MELCOR Accident Consequence Code System (MACCS) was performed. The QA and verification involved examination of the code and associated documentation for consistent and correct implementation of the models in an error-free FORTRAN computer code. The QA and verification was not intended to determine either the adequacy or appropriateness

C. A. Dobbe; E. R. Carlson; N. H. Marshall; E. S. Marwil; J. E. Tolli

1990-01-01

154

Coding for reliable satellite communications  

NASA Technical Reports Server (NTRS)

This research project was set up to study various kinds of coding techniques for error control in satellite and space communications for NASA Goddard Space Flight Center. During the project period, researchers investigated the following areas: (1) decoding of Reed-Solomon codes in terms of dual basis; (2) concatenated and cascaded error control coding schemes for satellite and space communications; (3) use of hybrid coding schemes (error correction and detection incorporated with retransmission) to improve system reliability and throughput in satellite communications; (4) good codes for simultaneous error correction and error detection, and (5) error control techniques for ring and star networks.

Gaarder, N. T.; Lin, S.

1986-01-01

155

Residential area deprivation predicts smoking habit independently of individual educational level and occupational social class. A cross sectional study in the Norfolk cohort of the European Investigation into Cancer (EPIC-Norfolk)  

PubMed Central

Objectives: To investigate the independent association between individual and area based measures of socioeconomic status and cigarette smoking habit. Design and setting: Cross sectional, population based study. Participants and methods: 12 579 men and 15 132 women aged 39–79 years living in the general community participating in the EPIC-Norfolk Study in 1993–1997. The association between social class, educational status, Townsend residential deprivation level, and cigarette smoking status was examined. Main outcome measures: Cigarette smoking status at baseline survey. Results: Social class, educational level, and residential deprivation level independently related to cigarette smoking habit in both men and women. Multivariate age adjusted odds ratios for current smoking in men were 1.62 (95% CI 1.45 to 1.81) for manual compared with non-manual social class, 1.32 (95% CI 1.17 to 1.48) for those with educational level less than O level compared with those with O level qualifications or higher and 1.84 (95% CI 1.62 to 2.08) for high versus low area deprivation level. For women, the odds ratios for current smoking for manual social class were 1.14 (95% CI 1.03 to 1.27); 1.31 (95% CI 1.18 to 1.46) for low educational level and 1.68 (95% CI 1.49 to 1.90) for high residential deprivation respectively. Conclusions: Residential deprivation level using the Townsend score, individual social class, and educational level all independently predict smoking habit in both men and women. Efforts to reduce cigarette smoking need to tackle not just individual but also area based factors. Understanding the specific factors in deprived areas that influence smoking habit may help inform preventive efforts.

Shohaimi, S; Luben, R; Wareham, N; Day, N; Bingham, S; Welch, A; Oakes, S; Khaw, K

2003-01-01

156

Constructions for finite-state codes  

NASA Technical Reports Server (NTRS)

A class of codes called finite-state (FS) codes is defined and investigated. These codes, which generalize both block and convolutional codes, are defined by their encoders, which are finite-state machines with parallel inputs and outputs. A family of upper bounds on the free distance of a given FS code is derived from known upper bounds on the minimum distance of block codes. A general construction for FS codes is then given, based on the idea of partitioning a given linear block into cosets of one of its subcodes, and it is shown that in many cases the FS codes constructed in this way have a d sub free which is as large as possible. These codes are found without the need for lengthy computer searches, and have potential applications for future deep-space coding systems. The issue of catastropic error propagation (CEP) for FS codes is also investigated.

Pollara, F.; Mceliece, R. J.; Abdel-Ghaffar, K.

1987-01-01

157

Coordinated design of coding and modulation systems  

NASA Technical Reports Server (NTRS)

The joint optimization of the coding and modulation systems employed in telemetry systems was investigated. Emphasis was placed on formulating inner and outer coding standards used by the Goddard Spaceflight Center. Convolutional codes were found that are nearly optimum for use with Viterbi decoding in the inner coding of concatenated coding systems. A convolutional code, the unit-memory code, was discovered and is ideal for inner system usage because of its byte-oriented structure. Simulations of sequential decoding on the deep-space channel were carried out to compare directly various convolutional codes that are proposed for use in deep-space systems.

Massey, J. L.; Ancheta, T.; Johannesson, R.; Lauer, G.; Lee, L.

1976-01-01

158

Comparative investigation of the long non-coding M-F genome region of wild-type and vaccine measles viruses.  

PubMed

The sequence of the 300 nucleotides region of the measles virus genome was determined that includes a part of the 3'-untranslated region of the matrix (M) gene, the intergenic region and a part of the 5'-untranslated region of the fusion (F) gene [M-F region] for vaccine strain Leningrad-16 and 14 wild-type isolates. The data obtained demonstrate the variability of this long non-coding M-F region. No mutations in this region of the genome were found which seem to be specific for vaccine strains of measles virus (MV). PMID:9672611

Heider, A; Santibanez, S; Tischer, A; Gerike, E; Tikhonova, N; Ignatyev, G; Mrazova, M; Enders, G; Schreier, E

1997-01-01

159

Code Cracker  

NSDL National Science Digital Library

Whether it's the genetic code, an ancient language, or patterns of light in a distant galaxy, scientists often have to play the role of decoder. In this activity, learners create a code to send secret messages for other learners to decode. When learners set up a free account at Kinetic City, they can answer bonus questions at the end of the activity as a quick assessment. As a larger assessment, learners can complete the Bug Blaster game after they've completed several activities.

Science, American A.

2009-01-01

160

Procedure Codes for SEER-Medicare Analyses  

Cancer.gov

The tables below contain codes for procedures that are frequently included in SEER-Medicare analyses. Please note that NCI provides these codes to assist researchers in analyses. Codes may change or may not be complete. NCI does not accept responsibility for the completeness or currency of the information below. Investigators should check that all relevant codes are included in their analysis.

161

Cyclic unequal error protection codes constructed from cyclic codes of composite length  

NASA Technical Reports Server (NTRS)

The distance structure of cyclic codes of composite length was investigated. A lower bound on the minimum distance for this class of codes is derived. In many cases, the lower bound gives the true minimum distance of a code. Then the distance structure of the direct sum of two cyclic codes of composite length were investigated. It was shown that, under certain conditions, the direct-sum code provides two levels of error correcting capability, and hence is a two-level unequal error protection (UEP) code. Finally, a class of two-level UEP cyclic direct-sum codes and a decoding algorithm for a subclass of these codes are presented.

Lin, Shu

1987-01-01

162

Quantum coding  

Microsoft Academic Search

A theorem is proven for quantum information theory that is analogous to the noiseless coding theorem of classical information theory. In the quantum result, the von Neumann entropy S of the density operator describing an ensemble of pure quantum signal states is equal to the number of spin-1\\/2 systems (``quantum bits'' or ``qubits'') necessary to represent the signal faithfully. The

Benjamin Schumacher

1995-01-01

163

Video coding  

US Patent & Trademark Office Database

Digitalized video images are compressed in several steps in order to provide a system for transmitting moving video pictures via narrow band channels, such as the telephone network. The system is based on any extension of the bit-plane coding technique to video sequences and lossy conditions. The compression technique can also be advantageously used in a lossless compression system. The system involves the steps of bit plane representation and skipping the least significant bit plane(s), shifting the pixels, coding with a Gray code, the use of segmentation, and motion-estimation/motion compensation and application of a transmit/not transmit/motion compensate (TX/NT/MC) procedure, exploiting of the temporal redundancy of two corresponding bit planes via an XOR operation on two successive images, and a plane-by-plane application of an extended RLEID technique. The RLEID technique includes coding a run of like binary symbols with one word, the run including a transition between the penultimate and ultimate binary symbol.

2001-03-27

164

CTEP Highlights — Site Code Policy  

Cancer.gov

The Site Code Working Group had released a final draft version of the Site Code Policy. The Site Code Working Group participants included staff from the Cooperative Groups, CTEP’s Pharmaceutical Management Branch (PMB), Clinical Trials Monitoring Branch (CTMB), and Clinical Investigations Branch (CIB), from the Division of Cancer Prevention (DCP), from contractors supporting the Cancer Trials Support Unit (CTSU), Enterprise Core Unit (ECU), AdEERs, and CDUS.

165

Multiple wavelet-tree-based image coding and robust transmission  

NASA Astrophysics Data System (ADS)

In this paper, we present techniques based on multiple wavelet-tree coding for robust image transmission. The algorithm of set partitioning in hierarchical trees (SPIHT) is a state-of-the-art technique for image compression. This variable length coding (VLC) technique, however, is extremely sensitive to channel errors. To improve the error resilience capability and in the meantime to keep the high source coding efficiency through VLC, we propose to encode each wavelet tree or a group of wavelet trees using SPIHT algorithm independently. Instead of encoding the entire image as one bitstream, multiple bitstreams are generated. Therefore, error propagation is limited within individual bitstream. Two methods based on subsampling and human visual sensitivity are proposed to group the wavelet trees. The multiple bitstreams are further protected by the rate compatible puncture convolutional (RCPC) codes. Unequal error protection are provided for both different bitstreams and different bit segments inside each bitstream. We also investigate the improvement of error resilience through error resilient entropy coding (EREC) and wavelet tree coding when channels are slightly corruptive. A simple post-processing technique is also proposed to alleviate the effect of residual errors. We demonstrate through simulations that systems with these techniques can achieve much better performance than systems transmitting a single bitstream in noisy environments.

Cao, Lei; Chen, Chang Wen

2004-10-01

166

Cooperative Space-Time Codes with Opportunistic Network Coding  

Microsoft Academic Search

Cooperative communications has emerged as one of the most efficient way of exploiting spatial diversity in wire- less communications. Cooperative communications is a strategy where users, besides transmitting their own information, also relay re-encoded version of other users' information to a common destination. In this paper, we investigate a scheme called space- time (ST) coded cooperation with opportunistic network coding,

Gordhan Das Menghwar; Bujar Krasniqi; Asif Ali Shah; Christoph F. Mecklenbrauker

167

Profile guided code positioning  

Microsoft Academic Search

This paper presents the results of our investigation of code positioning techniques using execution profile data as input into the compilation process. The primary objective of the positioning is to reduce the overhead of the instruction memory hierarchy.After initial investigation in the literature, we decided to implement two prototypes for the Hewlett-Packard Precision Architecture (PA-RISC). The first, built on top

Karl Pettis; Robert C. Hansen; Jack W. Davidson

2004-01-01

168

Discriminant Independent Component Analysis  

Microsoft Academic Search

A conventional linear model based on Negentropy maximization extracts statistically independent latent variables which may not be optimal to give a discriminant model with good classification performance. In this paper, a single-stage linear semisupervised extraction of discriminative independent fea- tures is proposed. Discriminant independent component analysis (dICA) presents a framework of linearly projecting multivariate data to a lower dimension where

Chandra Shekhar Dhir; Soo-Young Lee

2011-01-01

169

The Gray-Code Filter Kernels  

Microsoft Academic Search

In this paper, we introduce a family of filter kernels, the gray-code kernels (GCK) and demonstrate their use in image analysis. Filtering an image with a sequence of gray-code kernels is highly efficient and requires only two operations per pixel for each filter kernel, independent of the size or dimension of the kernel. We show that the family of kernels

Gil Ben-Artzi; Hagit Hel-Or; Yacov Hel-Or

2007-01-01

170

Content Independence in Multimedia Databases.  

ERIC Educational Resources Information Center

Investigates the role of data management in multimedia digital libraries, and its implications for the design of database management systems. Introduces the notions of content abstraction and content independence. Proposes a blueprint of a new class of database technology, which supports the basic functionality for the management of both content…

de Vries, Arjen P.

2001-01-01

171

Seals Code Development Workshop  

NASA Technical Reports Server (NTRS)

Seals Workshop of 1995 industrial code (INDSEAL) release include ICYL, GCYLT, IFACE, GFACE, SPIRALG, SPIRALI, DYSEAL, and KTK. The scientific code (SCISEAL) release includes conjugate heat transfer and multidomain with rotordynamic capability. Several seals and bearings codes (e.g., HYDROFLEX, HYDROTRAN, HYDROB3D, FLOWCON1, FLOWCON2) are presented and results compared. Current computational and experimental emphasis includes multiple connected cavity flows with goals of reducing parasitic losses and gas ingestion. Labyrinth seals continue to play a significant role in sealing with face, honeycomb, and new sealing concepts under investigation for advanced engine concepts in view of strict environmental constraints. The clean sheet approach to engine design is advocated with program directions and anticipated percentage SFC reductions cited. Future activities center on engine applications with coupled seal/power/secondary flow streams.

Hendricks, Robert C. (Compiler); Liang, Anita D. (Compiler)

1996-01-01

172

Implementation issues in source coding  

NASA Technical Reports Server (NTRS)

An edge preserving image coding scheme which can be operated in both a lossy and a lossless manner was developed. The technique is an extension of the lossless encoding algorithm developed for the Mars observer spectral data. It can also be viewed as a modification of the DPCM algorithm. A packet video simulator was also developed from an existing modified packet network simulator. The coding scheme for this system is a modification of the mixture block coding (MBC) scheme described in the last report. Coding algorithms for packet video were also investigated.

Sayood, Khalid; Chen, Yun-Chung; Hadenfeldt, A. C.

1989-01-01

173

Cascaded Coding Scheme for Error Control.  

National Technical Information Service (NTIS)

A cascaded coding scheme for error control was investigated. The scheme employs a combination of hard and soft decisions in decoding. Error performance is analyzed. If the inner and outer codes are chosen properly, extremely high reliability can be attain...

T. Kasami S. Lin

1985-01-01

174

Role of long non-coding RNA HULC in cell proliferation, apoptosis and tumor metastasis of gastric cancer: a clinical and in vitro investigation.  

PubMed

Long non-coding RNAs (lncRNAs) are emerging as key molecules in human cancer. Highly upregulated in liver cancer (HULC), an lncRNA, has recently been revealed to be involved in hepatocellular carcinoma development and progression. It remains unclear, however, whether HULC plays an oncogenic role in human gastric cancer (GC). In the present study, we demonstrated that HULC was significantly overexpressed in GC cell lines and GC tissues compared with normal controls, and this overexpression was correlated with lymph node metastasis, distant metastasis and advanced tumor node metastasis stages. In addition, a receiver operating characteristic (ROC) curve was constructed to evaluate the diagnostic values and the area under the ROC curve of HULC was up to 0.769. To uncover its functional importance, gain- and loss-of-function studies were performed to evaluate the effect of HULC on cell proliferation, apoptosis and invasion in vitro. Overexpression of HULC promoted proliferation and invasion and inhibited cell apoptosis in SGC7901 cells, while knockdown of HULC in SGC7901 cells showed the opposite effect. Mechanistically, we discovered that overexpression of HULC could induce patterns of autophagy in SGC7901 cells; more importantly, autophagy inhibition increased overexpression of HULC cell apoptosis. We also determined that silencing of HULC effectively reversed the epithelial-to-mesenchymal transition (EMT) phenotype. In summary, our results suggest that HULC may play an important role in the growth and tumorigenesis of human GC, which provides us with a new biomarker in GC and perhaps a potential target for GC prevention, diagnosis and therapeutic treatment. PMID:24247585

Zhao, Yan; Guo, Qinhao; Chen, Jiejing; Hu, Jun; Wang, Shuwei; Sun, Yueming

2014-01-01

175

Allele coding in genomic evaluation  

PubMed Central

Background Genomic data are used in animal breeding to assist genetic evaluation. Several models to estimate genomic breeding values have been studied. In general, two approaches have been used. One approach estimates the marker effects first and then, genomic breeding values are obtained by summing marker effects. In the second approach, genomic breeding values are estimated directly using an equivalent model with a genomic relationship matrix. Allele coding is the method chosen to assign values to the regression coefficients in the statistical model. A common allele coding is zero for the homozygous genotype of the first allele, one for the heterozygote, and two for the homozygous genotype for the other allele. Another common allele coding changes these regression coefficients by subtracting a value from each marker such that the mean of regression coefficients is zero within each marker. We call this centered allele coding. This study considered effects of different allele coding methods on inference. Both marker-based and equivalent models were considered, and restricted maximum likelihood and Bayesian methods were used in inference. Results Theoretical derivations showed that parameter estimates and estimated marker effects in marker-based models are the same irrespective of the allele coding, provided that the model has a fixed general mean. For the equivalent models, the same results hold, even though different allele coding methods lead to different genomic relationship matrices. Calculated genomic breeding values are independent of allele coding when the estimate of the general mean is included into the values. Reliabilities of estimated genomic breeding values calculated using elements of the inverse of the coefficient matrix depend on the allele coding because different allele coding methods imply different models. Finally, allele coding affects the mixing of Markov chain Monte Carlo algorithms, with the centered coding being the best. Conclusions Different allele coding methods lead to the same inference in the marker-based and equivalent models when a fixed general mean is included in the model. However, reliabilities of genomic breeding values are affected by the allele coding method used. The centered coding has some numerical advantages when Markov chain Monte Carlo methods are used.

2011-01-01

176

Image subband coding using arithmetic coded trellis coded quantization  

Microsoft Academic Search

A method is presented for encoding memoryless sources using trellis coded quantization (TCQ) with uniform thresholds. The trellis symbols are entropy-coded using arithmetic coding. The performance of the arithmetic coded uniform threshold TCQ, for encoding the family of generalized Gaussian densities, is compared with uniform threshold quantization (UTQ) and the Shannon lower bound (SLB). At high rates, the method performs

Rajan L. Joshi; Valerie J. Crump; Thomas R. Fischer

1995-01-01

177

Investigation of Plant Control Strategies for the Supercritical C0(Sub 2) Brayton Cycle for a Sodium-Cooled Fast Reactor Using the Plant Dynamics Code.  

National Technical Information Service (NTIS)

The development of a control strategy for the supercritical CO(sub 2) (S-CO(sub 2)) Brayton cycle has been extended to the investigation of alternate control strategies for a Sodium-Cooled Fast Reactor (SFR) nuclear power plant incorporating a S-CO(sub 2)...

A. Moisseytsev J. Sienicki

2011-01-01

178

Joint Source and Channel Coding using Punctured Ring Convolutional Coded CPM  

Microsoft Academic Search

In this paper, a novel trellis source encoding scheme based on punctured ring convolutional codes is presented. Joint source and channel coding (JSCC) using trellis coded continuous phase modulation (CPM) with punctured convolutional codes over rings is investigated. The channels considered are the additive white gaussian noise (AWGN) channel and the Rayleigh fading channel. Optimal soft decoding for the proposed

Zihuai Lin; Tor Aulin

2008-01-01

179

On the error probability of general tree and trellis codes with applications to sequential decoding  

NASA Technical Reports Server (NTRS)

An upper bound on the average error probability for maximum-likelihood decoding of the ensemble of random binary tree codes is derived and shown to be independent of the length of the tree. An upper bound on the average error probability for maximum-likelihood decoding of the ensemble of random L-branch binary trellis codes of rate R = 1/n is derived which separates the effects of the tail length T and the memory length M of the code. It is shown that the bound is independent of the length L of the information sequence. This implication is investigated by computer simulations of sequential decoding utilizing the stack algorithm. These simulations confirm the implication and further suggest an empirical formula for the true undetected decoding error probability with sequential decoding.

Johannesson, R.

1973-01-01

180

The investigation of tethered satellite system dynamics  

NASA Technical Reports Server (NTRS)

The analysis of the rotational dynamics of the satellite was focused on the rotational amplitude increase of the satellite, with respect to the tether, during retrieval. The dependence of the rotational amplitude upon the tether tension variation to the power 1/4 was thoroughly investigated. The damping of rotational oscillations achievable by reel control was also quantified while an alternative solution that makes use of a lever arm attached with a universal joint to the satellite was proposed. Comparison simulations between the Smithsonian Astrophysical Observatory and the Martin Marietta (MMA) computer code of reteival maneuvers were also carried out. The agreement between the two, completely independent, codes was extremely close, demonstrating the reliability of the models. The slack tether dynamics during reel jams was analytically investigated in order to identify the limits of applicability of the SLACK3 computer code to this particular case. Test runs with SLACK3 were also carried out.

Lorenzini, E. C.

1986-01-01

181

Factors Affecting Coding Errors.  

National Technical Information Service (NTIS)

This Memorandum describes experiments which sought to identify the factors that contribute to coding errors. The experiments used code-stimulus materials: numeric codes, consisting only of numbers; alpha codes, consisting only of letters; alpha-numeric co...

S. Owsowtiz, A. Sweetland

1965-01-01

182

Codes with special correlation.  

NASA Technical Reports Server (NTRS)

Uniform binary codes with special correlation including transorthogonality and simplex code, Hadamard matrices and difference sets uniform binary codes with special correlation including transorthogonality and simplex code, Hadamard matrices and difference sets

Baumert, L. D.

1964-01-01

183

Federal Building and Fire Safety Investigation of the World Trade Center Disaster: Comparison of Codes, Standards, and Practices in Use at the Time of the Design and Construction of World Trade Center 1, 2, and 7. NIST NCSTAR 1-1E.  

National Technical Information Service (NTIS)

This report was prepared to support the goals and objectives of the analysis of building and fire codes and practices of the National Institute of Standards and Technology World Trade Center (WTC) Investigation. The report provides a comparison and summar...

J. C. Razza R. A. Grill

2005-01-01

184

Production code control system for hydrodynamics simulations  

SciTech Connect

We describe how the Production Code Control System (pCCS), written in Perl, has been used to control and monitor the execution of a large hydrodynamics simulation code in a production environment. We have been able to integrate new, disparate, and often independent, applications into the PCCS framework without the need to modify any of our existing application codes. Both users and code developers see a consistent interface to the simulation code and associated applications regardless of the physical platform, whether an MPP, SMP, server, or desktop workstation. We will also describe our use of Perl to develop a configuration management system for the simulation code, as well as a code usage database and report generator. We used Perl to write a backplane that allows us plug in preprocessors, the hydrocode, postprocessors, visualization tools, persistent storage requests, and other codes. We need only teach PCCS a minimal amount about any new tool or code to essentially plug it in and make it usable to the hydrocode. PCCS has made it easier to link together disparate codes, since using Perl has removed the need to learn the idiosyncrasies of system or RPC programming. The text handling in Perl makes it easy to teach PCCS about new codes, or changes to existing codes.

Slone, D.M.

1997-08-18

185

Investigating the Influence of the Added Mass Effect to Marine Hydrokinetic Horizontal-Axis Turbines Using a General Dynamic Wake Wind Turbine Code  

SciTech Connect

This paper describes a recent study to investigate the applicability of a horizontal-axis wind turbine (HAWT) structural dynamics and unsteady aerodynamics analysis program (FAST and AeroDyn respectively) to modeling the forces on marine hydrokinetic (MHK) turbines. This paper summarizes the added mass model that has been added to AeroDyn. The added mass model only includes flow acceleration perpendicular to the rotor disc, and ignores added mass forces caused by blade deflection. A model of the National Renewable Energy Laboratory's (NREL) Unsteady Aerodynamics Experiment (UAE) Phase VI wind turbine was analyzed using FAST and AeroDyn with sea water conditions and the new added mass model. The results of this analysis exhibited a 3.6% change in thrust for a rapid pitch case and a slight change in amplitude and phase of thrust for a case with 30{sup o} of yaw.

Maniaci, D. C.; Li, Y.

2011-10-01

186

Symmetric Distributed Source Coding using LDPC Code  

Microsoft Academic Search

Distributed source coding is a promising enabling technology for sensor network applications. Symmetric distributed source coding can achieve the entire Slepian-Wolf rate region and offer sensor network applications a wide range of options to compress and transmit data. In this paper, we design a new symmetric distributed coding scheme that realize the benefits of both simplified code construction and bit

Baochun Bai; Yang Yang; Pierre Boulanger; Janelle J. Harms

2008-01-01

187

Longwave infrared (LWIR) coded aperture dispersive spectrometer.  

PubMed

We describe a static aperture-coded, dispersive longwave infrared (LWIR) spectrometer that uses a microbolometer array at the detector plane. The two-dimensional aperture code is based on a row-doubled Hadamard mask with transmissive and opaque openings. The independent column code nature of the matrix makes for a mathematically well-defined pattern that spatially and spectrally maps the source information to the detector plane. Post-processing techniques on the data provide spectral estimates of the source. Comparative experimental results between a slit and coded aperture for emission spectroscopy from a CO(2) laser are demonstrated. PMID:19532832

Fernandez, C; Guenther, B D; Gehm, M E; Brady, D J; Sullivan, M E

2007-04-30

188

Small Wind Independent Testing.  

National Technical Information Service (NTIS)

This fact sheet describes the Small Wind Independent Testing at the NWTC and the Regional Test Center's project. NREL and the U.S. Department of Energy's (DOE) Wind and Water Power Program established the Small Wind Independent Testing project in 2008 and...

2010-01-01

189

Central bank Financial Independence  

Microsoft Academic Search

Central bank independence is a multifaceted institutional design. The financial component has been seldom analysed. This paper intends to set a comprehensive conceptual background for central bank financial independence. Quite often central banks are modelled as robot like maximizers of some goal. This perspective neglects the fact that central bank functions are inevitably deployed on its balance sheet and have

J. Ramon Martinez-Resano

2004-01-01

190

American Independence. Fifth Grade.  

ERIC Educational Resources Information Center

This fifth grade teaching unit covers early conflicts between the American colonies and Britain, battles of the American Revolutionary War, and the Declaration of Independence. Knowledge goals address the pre-revolutionary acts enforced by the British, the concepts of conflict and independence, and the major events and significant people from the…

Crosby, Annette

191

New coding advances for deep space communications  

NASA Technical Reports Server (NTRS)

Advances made in error-correction coding for deep space communications are described. The code believed to be the best is a (15, 1/6) convolutional code, with maximum likelihood decoding; when it is concatenated with a 10-bit Reed-Solomon code, it achieves a bit error rate of 10 to the -6th, at a bit SNR of 0.42 dB. This code outperforms the Voyager code by 2.11 dB. The use of source statics in decoding convolutionally encoded Voyager images from the Uranus encounter is investigated, and it is found that a 2 dB decoding gain can be achieved.

Yuen, Joseph H.

1987-01-01

192

Collaborative decoding of interleaved Reed-Solomon codes and concatenated code designs  

Microsoft Academic Search

Interleaved Reed-Solomon codes are applied in numerous data processing, data transmission, and data storage systems. They are generated by interleaving several codewords of ordinary Reed-Solomon codes. Usually, these codewords are decoded independently by classical algebraic decoding methods. However, by collaborative algebraic decoding approaches, such interleaved schemes allow the correction of error patterns beyond half the minimum distance, provided that the

Georg Schmidt; Vladimir R. Sidorenko; Martin Bossert

2009-01-01

193

Collaborative Decoding of Interleaved Reed-Solomon Codes and Concatenated Code Designs  

Microsoft Academic Search

Interleaved Reed-Solomon codes are applied in numerous data processing, data transmission, and data storage systems. They are generated by interleaving several codewords of ordinary Reed-Solomon codes. Usually, these codewords are decoded independently by classical algebraic decoding methods. However, by collaborative algebraic decoding approaches, such interleaved schemes allow the correction of error patterns beyond half the minimum distance, provided that the

Georg Schmidt; Vladimir R. Sidorenko; Martin Bossert

2006-01-01

194

Exceptional error minimization in putative primordial genetic codes  

PubMed Central

Background The standard genetic code is redundant and has a highly non-random structure. Codons for the same amino acids typically differ only by the nucleotide in the third position, whereas similar amino acids are encoded, mostly, by codon series that differ by a single base substitution in the third or the first position. As a result, the code is highly albeit not optimally robust to errors of translation, a property that has been interpreted either as a product of selection directed at the minimization of errors or as a non-adaptive by-product of evolution of the code driven by other forces. Results We investigated the error-minimization properties of putative primordial codes that consisted of 16 supercodons, with the third base being completely redundant, using a previously derived cost function and the error minimization percentage as the measure of a code's robustness to mistranslation. It is shown that, when the 16-supercodon table is populated with 10 putative primordial amino acids, inferred from the results of abiotic synthesis experiments and other evidence independent of the code's evolution, and with minimal assumptions used to assign the remaining supercodons, the resulting 2-letter codes are nearly optimal in terms of the error minimization level. Conclusion The results of the computational experiments with putative primordial genetic codes that contained only two meaningful letters in all codons and encoded 10 to 16 amino acids indicate that such codes are likely to have been nearly optimal with respect to the minimization of translation errors. This near-optimality could be the outcome of extensive early selection during the co-evolution of the code with the primordial, error-prone translation system, or a result of a unique, accidental event. Under this hypothesis, the subsequent expansion of the code resulted in a decrease of the error minimization level that became sustainable owing to the evolution of a high-fidelity translation system. Reviewers This article was reviewed by Paul Higgs (nominated by Arcady Mushegian), Rob Knight, and Sandor Pongor. For the complete reports, go to the Reviewers' Reports section.

2009-01-01

195

Speaker Verification Using Coded Speech  

Microsoft Academic Search

The implementation of a pseudo text-independent Speaker Verifica- tion system is described. This system was designed to use only information ex- tracted directly from the coded parameters embedded in the ITU-T G.729 bit- stream. Experiments were performed over the YOHO database (1). The feature vector as a short-time representation of speech consists of 16 LPC-Cepstral co- efficients, as well as

Antonio Moreno-daniel; Biing-Hwang Juang; Juan Arturo Nolazco-flores

2004-01-01

196

Coding schemes for confidential communications  

Microsoft Academic Search

In this paper, the hybrid automatic retransmission request (HARQ) coding scheme is revisited for a block-fading wire-tap channel, in which two legitimate users communicate over a block-fading channel in the presence of a passive eavesdropper who intercepts the transmissions through an independent block-fading channel. In this model, the transmitter obtains a 1-bit ACK\\/NACK feedback from the legitimate receiver via an

Xiaojun Tang; Ruoheng Liu; P. Spasojevic; H. V. Poor

2008-01-01

197

A construction for low density parity check convolutional codes based on quasi-cyclic block codes  

Microsoft Academic Search

A set of convolutional codes with low density parity check matrices is derived from a class of quasi-cyclic low density parity check block codes. Their performance when decoded using the belief propagation algorithm is investigated.

Arvind Sridharan; Daniel J. Costello Jr; R. M. Tanner

2002-01-01

198

Pulsed Inductive Thruster (PIT): Modeling and Validation Using the MACH2 Code  

NASA Technical Reports Server (NTRS)

Numerical modeling of the Pulsed Inductive Thruster exercising the magnetohydrodynamics code, MACH2 aims to provide bilateral validation of the thruster's measured performance and the code's capability of capturing the pertinent physical processes. Computed impulse values for helium and argon propellants demonstrate excellent correlation to the experimental data for a range of energy levels and propellant-mass values. The effects of the vacuum tank wall and massinjection scheme were investigated to show trivial changes in the overall performance. An idealized model for these energy levels and propellants deduces that the energy expended to the internal energy modes and plasma dissipation processes is independent of the propellant type, mass, and energy level.

Schneider, Steven (Technical Monitor); Mikellides, Pavlos G.

2003-01-01

199

Frequency Independent Antennas.  

National Technical Information Service (NTIS)

The basic principles of frequency independent operation are reviewed. The connection between the self-complementary condition for planar structures and the dipole arrays with switched connections is an interesting point. The vital importance of radiation ...

V. H. Rumsey

1965-01-01

200

Media independent interface  

NASA Technical Reports Server (NTRS)

The work done on the Media Independent Interface (MII) Interface Control Document (ICD) program is described and recommendations based on it were made. Explanations and rationale for the content of the ICD itself are presented.

1987-01-01

201

Homological stabilizer codes  

SciTech Connect

In this paper we define homological stabilizer codes on qubits which encompass codes such as Kitaev's toric code and the topological color codes. These codes are defined solely by the graphs they reside on. This feature allows us to use properties of topological graph theory to determine the graphs which are suitable as homological stabilizer codes. We then show that all toric codes are equivalent to homological stabilizer codes on 4-valent graphs. We show that the topological color codes and toric codes correspond to two distinct classes of graphs. We define the notion of label set equivalencies and show that under a small set of constraints the only homological stabilizer codes without local logical operators are equivalent to Kitaev's toric code or to the topological color codes. - Highlights: Black-Right-Pointing-Pointer We show that Kitaev's toric codes are equivalent to homological stabilizer codes on 4-valent graphs. Black-Right-Pointing-Pointer We show that toric codes and color codes correspond to homological stabilizer codes on distinct graphs. Black-Right-Pointing-Pointer We find and classify all 2D homological stabilizer codes. Black-Right-Pointing-Pointer We find optimal codes among the homological stabilizer codes.

Anderson, Jonas T., E-mail: jonastyleranderson@gmail.com

2013-03-15

202

ROBUST INDEPENDENT COMPONENT ANALYSIS  

Microsoft Academic Search

ABSTRACT: Independent component,analysis (ICA) aims at decomposing,an observed random,vector into statistically independent vari- ables. Deflation-based implementations, such as the popula r one-unit FastICA algorithm and its variants, extract the i ndependent components one after another. A novel method for deflationar y ICA, referred to as RobustICA, is put forward in this paper. This

Vicente Zarzoso; Pierre Comon

2009-01-01

203

Encyclopedia of Sparse Graph Codes  

Microsoft Academic Search

Evaluation of Gallager codes for low error tolerance, short block length andhigh rate applications.Sparse graph codes include Gallager codes, Tanner codes, MN codes Repeat--Accumulate codes (RA codes), and turbo codes, all of which have near--Shannonlimit performance.This paper (which is still in preparation) describes empirical properties of a wideselection of these codes, comparing in particular the codes\\

David J. C. Mackay

1999-01-01

204

Linear Congruential Trellis Source Codes: Design and Analysis  

Microsoft Academic Search

Rate-distortion trellis source codes are developed for quantizing memoryless independent and identically distributed (i.i.d.) sources. The codes are generated by simple linear congruential recursions. The method generates codes at a variety of rates including fractional ones; reproducer sets can be large, a crucial advantage with certain sources. Axioms for good code construction are developed that are based on recursion properties

Tomas Eriksson; John B. Anderson; Norbert Goertz

2007-01-01

205

Correlated algebraic-geometric codes  

NASA Astrophysics Data System (ADS)

We define a new family of error-correcting codes based on algebraic curves over finite fields, and develop efficient list decoding algorithms for them. Our codes extend the class of algebraic-geometric (AG) codes via a (nonobvious) generalization of the approach in the recent breakthrough work of Parvaresh and Vardy (2005). Our work shows that the PV framework applies to fairly general settings by elucidating the key algebraic concepts underlying it. Also, more importantly, AG codes of arbitrary block length exist over fixed alphabets Sigma , thus enabling us to establish new trade-offs between the list decoding radius and rate over a bounded alphabet size. The work of Parvaresh and Vardy (2005) was extended in Guruswami and Rudra (2006) to give explicit codes that achieve the list decoding capacity (optimal trade-off between rate and fraction of errors corrected) over large alphabets. A similar extension of this work along the lines of Guruswami and Rudra could have substantial impact. Indeed, it could give better trade-offs than currently known over a fixed alphabet (say, GF(2^{12}) ), which in turn, upon concatenation with a fixed, well-understood binary code, could take us closer to the list decoding capacity for binary codes. This may also be a promising way to address the significant complexity drawback of the result of Guruswami and Rudra, and to enable approaching capacity with bounded list size independent of the block length (the list size and decoding complexity in their work are both n^{Omega(1/\\varepsilon)} where \\varepsilon is the distance to capacity). Similar to algorithms for AG codes from Guruswami and Sudan (1999) and (2001), our encoding/decoding algorithms run in polynomial time assuming a natural polynomial-size representation of the code. For codes based on a specific ``optimal'' algebraic curve, we also present an expected polynomial time algorithm to construct the requisite representation. This in turn fills an important void in the literature by presenting an efficient construction of the representation often assumed in the list decoding algorithms for AG codes.

Guruswami, Venkatesan; Patthak, Anindya C.

2008-03-01

206

Layered Low-Density Generator Matrix Codes for Super High Definition Scalable Video Coding System  

NASA Astrophysics Data System (ADS)

In this paper, we introduce layered low-density generator matrix (Layered-LDGM) codes for super high definition (SHD) scalable video systems. The layered-LDGM codes maintain the correspondence relationship of each layer from the encoder side to the decoder side. This resulting structure supports partial decoding. Furthermore, the proposed layered-LDGM codes create highly efficient forward error correcting (FEC) data by considering the relationship between each scalable component. Therefore, the proposed layered-LDGM codes raise the probability of restoring the important components. Simulations show that the proposed layered-LDGM codes offer better error resiliency than the existing method which creates FEC data for each scalable component independently. The proposed layered-LDGM codes support partial decoding and raise the probability of restoring the base component. These characteristics are very suitable for scalable video coding systems.

Tonomura, Yoshihide; Shirai, Daisuke; Nakachi, Takayuki; Fujii, Tatsuya; Kiya, Hitoshi

207

Utilizing sequence intrinsic composition to classify protein-coding and long non-coding transcripts  

PubMed Central

It is a challenge to classify protein-coding or non-coding transcripts, especially those re-constructed from high-throughput sequencing data of poorly annotated species. This study developed and evaluated a powerful signature tool, Coding-Non-Coding Index (CNCI), by profiling adjoining nucleotide triplets to effectively distinguish protein-coding and non-coding sequences independent of known annotations. CNCI is effective for classifying incomplete transcripts and sense–antisense pairs. The implementation of CNCI offered highly accurate classification of transcripts assembled from whole-transcriptome sequencing data in a cross-species manner, that demonstrated gene evolutionary divergence between vertebrates, and invertebrates, or between plants, and provided a long non-coding RNA catalog of orangutan. CNCI software is available at http://www.bioinfo.org/software/cnci.

Sun, Liang; Luo, Haitao; Bu, Dechao; Zhao, Guoguang; Yu, Kuntao; Zhang, Changhai; Liu, Yuanning; Chen, Runsheng; Zhao, Yi

2013-01-01

208

A Generalization of the Parallel Error Correcting Codes by Allowing Some Random Errors  

Microsoft Academic Search

SUMMARY This paper generalizes parallel error correcting codes pro- posed by Ahlswede et al. over a new type of multiple access channel called parallel error channel. The generalized parallel error correcting codes can handle with more errors compared with the original ones. We show con- struction methods of independent and non-independent parallel error cor- recting codes and decoding methods. We

Hideki Yagi; Toshiyasu Matsushima; Shigeichi Hirasawa

2007-01-01

209

An introduction to QR Codes: linking libraries and mobile patrons.  

PubMed

QR codes, or "Quick Response" codes, are two-dimensional barcodes that can be scanned by mobile smartphone cameras. These codes can be used to provide fast access to URLs, telephone numbers, and short passages of text. With the rapid adoption of smartphones, librarians are able to use QR codes to promote services and help library users find materials quickly and independently. This article will explain what QR codes are, discuss how they can be used in the library, and describe issues surrounding their use. A list of resources for generating and scanning QR codes is also provided. PMID:21800986

Hoy, Matthew B

2011-01-01

210

Independent Component Analysis in Spiking Neurons  

PubMed Central

Although models based on independent component analysis (ICA) have been successful in explaining various properties of sensory coding in the cortex, it remains unclear how networks of spiking neurons using realistic plasticity rules can realize such computation. Here, we propose a biologically plausible mechanism for ICA-like learning with spiking neurons. Our model combines spike-timing dependent plasticity and synaptic scaling with an intrinsic plasticity rule that regulates neuronal excitability to maximize information transmission. We show that a stochastically spiking neuron learns one independent component for inputs encoded either as rates or using spike-spike correlations. Furthermore, different independent components can be recovered, when the activity of different neurons is decorrelated by adaptive lateral inhibition.

Savin, Cristina; Joshi, Prashant; Triesch, Jochen

2010-01-01

211

Distributed single source coding with side information  

NASA Astrophysics Data System (ADS)

In the paper we advocate image compression technique in the scope of distributed source coding framework. The novelty of the proposed approach is twofold: classical image compression is considered from the positions of source coding with side information and, contrarily to the existing scenarios, where side information is given explicitly, side information is created based on deterministic approximation of local image features. We consider an image in the transform domain as a realization of a source with a bounded codebook of symbols where each symbol represents a particular edge shape. The codebook is image independent and plays the role of auxiliary source. Due to the partial availability of side information at both encoder and decoder we treat our problem as a modification of Berger-Flynn-Gray problem and investigate a possible gain over the solutions when side information is either unavailable or available only at decoder. Finally, we present a practical compression algorithm for passport photo images based on our concept that demonstrates the superior performance in very low bit rate regime.

Vila-Forcen, Jose E.; Koval, Oleksiy; Voloshynovskiy, Sviatoslav V.

2004-01-01

212

Categorical Shape and Color Coding by Pigeons  

Microsoft Academic Search

Categorical coding is the tendency to respond similarly to discriminated stimuli. Past research indicates that pigeons can categorize colors according to at least three spectral regions. Two present experiments assessed the categorical coding of shapes and the existence of a higher order color category (all colors). Pigeons were trained on two independent tasks (matching-to-sample, and oddity-from-sample). One task involved red

Thomas R. Zentall; Pamela Jackson-Smith; Joyce A. Jagielo; Gary B. Nallan

1986-01-01

213

In short, powerlifting Australia is a strong supporter of the proposal to establish an independent Sports Doping Investigation Board. In actual fact, we have approached the Australian Sports Commission a number of times over the years to request such an initiative and it is pleasing to finally see some movement towards this becoming a reality  

Microsoft Academic Search

These difficulties for Powerlifting Australia would no doubt also apply for many small and medium size sporting bodies. We thus strongly support the establishment of an independent Sports Doping Investigation Board. We envisage such a Board as taking doping offence cases through the investigatory and hearing phases, with the requirement being for sporting organizations to apply the penalties of suspension,

Robert Wilks

214

Neuronal adaptation translates stimulus gaps into a population code.  

PubMed

Neurons in sensory pathways exhibit a vast multitude of adaptation behaviors, which are assumed to aid the encoding of temporal stimulus features and provide the basis for a population code in higher brain areas. Here we study the transition to a population code for auditory gap stimuli both in neurophysiological recordings and in a computational network model. Independent component analysis (ICA) of experimental data from the inferior colliculus of Mongolian gerbils reveals that the network encodes different gap sizes primarily with its population firing rate within 30 ms after the presentation of the gap, where longer gap size evokes higher network activity. We then developed a computational model to investigate possible mechanisms of how to generate the population code for gaps. Phenomenological (ICA) and functional (discrimination performance) analyses of our simulated networks show that the experimentally observed patterns may result from heterogeneous adaptation, where adaptation provides gap detection at the single neuron level and neuronal heterogeneity ensures discriminable population codes for the whole range of gap sizes in the input. Furthermore, our work suggests that network recurrence additionally enhances the network's ability to provide discriminable population patterns. PMID:24759970

Yuan, Chun-Wei; Khouri, Leila; Grothe, Benedikt; Leibold, Christian

2014-01-01

215

Neuronal Adaptation Translates Stimulus Gaps into a Population Code  

PubMed Central

Neurons in sensory pathways exhibit a vast multitude of adaptation behaviors, which are assumed to aid the encoding of temporal stimulus features and provide the basis for a population code in higher brain areas. Here we study the transition to a population code for auditory gap stimuli both in neurophysiological recordings and in a computational network model. Independent component analysis (ICA) of experimental data from the inferior colliculus of Mongolian gerbils reveals that the network encodes different gap sizes primarily with its population firing rate within 30 ms after the presentation of the gap, where longer gap size evokes higher network activity. We then developed a computational model to investigate possible mechanisms of how to generate the population code for gaps. Phenomenological (ICA) and functional (discrimination performance) analyses of our simulated networks show that the experimentally observed patterns may result from heterogeneous adaptation, where adaptation provides gap detection at the single neuron level and neuronal heterogeneity ensures discriminable population codes for the whole range of gap sizes in the input. Furthermore, our work suggests that network recurrence additionally enhances the network's ability to provide discriminable population patterns.

Yuan, Chun-Wei; Khouri, Leila; Grothe, Benedikt; Leibold, Christian

2014-01-01

216

Independent power generator  

NASA Technical Reports Server (NTRS)

A gas turbine powered aircraft auxiliary power system is described which is capable of efficiently supplying all aircraft auxiliary services both in flight and on the ground and is further capable of operating independently of the aircraft main engines. The system employs multiple gas turbine compressor stages, thereby accomplishing cabin pressurization, ventilation and heating.

Young, R. N. (inventor)

1978-01-01

217

Independent Mathematical Modeling.  

ERIC Educational Resources Information Center

Argues that a major difficulty in learning how to do mathematical modeling is in the first independent run through the modeling cycle. Reviews a case study (N=12) on mathematical modeling and presents the conclusions in three sections: (1) the choice of task; (2) the presentation of the task; and (3) tutor intervention and support. (ASK)

Smith, D. N.

1997-01-01

218

Independence, Disengagement, and Discipline  

ERIC Educational Resources Information Center

School disengagement is linked to a lack of opportunities for students to fulfill their needs for independence and self-determination. Young people have little say about what, when, where, and how they will learn, the criteria used to assess their success, and the content of school and classroom rules. Traditional behavior management discourages…

Rubin, Ron

2012-01-01

219

Caring about Independent Lives  

ERIC Educational Resources Information Center

With the rhetoric of independence, new cash for care systems were introduced in many developed welfare states at the end of the 20th century. These systems allow local authorities to pay people who are eligible for community care services directly, to enable them to employ their own careworkers. Despite the obvious importance of the careworker's…

Christensen, Karen

2010-01-01

220

Postcard from Independence, Mo.  

ERIC Educational Resources Information Center

This article reports results showing that the Independence, Missori school district failed to meet almost every one of its improvement goals under the No Child Left Behind Act. The state accreditation system stresses improvement over past scores, while the federal law demands specified amounts of annual progress toward the ultimate goal of 100…

Archer, Jeff

2004-01-01

221

Code-Switching: L1-Coded Mediation in a Kindergarten Foreign Language Classroom  

ERIC Educational Resources Information Center

This paper is based on a qualitative inquiry that investigated the role of teachers' mediation in three different modes of coding in a kindergarten foreign language classroom in China (i.e. L2-coded intralinguistic mediation, L1-coded cross-lingual mediation, and L2-and-L1-mixed mediation). Through an exploratory examination of the varying effects…

Lin, Zheng

2012-01-01

222

Low-Delay Distributed Source Coding: Bounds and Performance of Practical Codes  

Microsoft Academic Search

The performance of distributed source coding methods based on scalar quanti- zation followed by scalar entropy coding is investigated. For a fixed quantizer, the problem is converted to that of zero-error entropy coding for bipartite graphs with a special structure. It is then experimentally shown that for bipartite graphs corre- sponding to jointly Gaussian sources and high-resolution uniform quantization, (i)

Ozgun Bursalioglu; Ertem Tuncel

223

Accumulate repeat accumulate codes  

NASA Technical Reports Server (NTRS)

In this paper we propose an innovative channel coding scheme called 'Accumulate Repeat Accumulate codes' (ARA). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes, thus belief propagation can be used for iterative decoding of ARA codes on a graph. The structure of encoder for this class can be viewed as precoded Repeat Accumulate (RA) code or as precoded Irregular Repeat Accumulate (IRA) code, where simply an accumulator is chosen as a precoder. Thus ARA codes have simple, and very fast encoder structure when they representing LDPC codes. Based on density evolution for LDPC codes through some examples for ARA codes, we show that for maximum variable node degree 5 a minimum bit SNR as low as 0.08 dB from channel capacity for rate 1/2 can be achieved as the block size goes to infinity. Thus based on fixed low maximum variable node degree, its threshold outperforms not only the RA and IRA codes but also the best known LDPC codes with the dame maximum node degree. Furthermore by puncturing the accumulators any desired high rate codes close to code rate 1 can be obtained with thresholds that stay close to the channel capacity thresholds uniformly. Iterative decoding simulation results are provided. The ARA codes also have projected graph or protograph representation that allows for high speed decoder implementation.

Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

2004-01-01

224

Rate 3/4 convolutional coding of 16-PSK - Code design and performance study  

NASA Technical Reports Server (NTRS)

Convolutional coding coupled with 16-PSK modulation is investigated for bandwidth efficient transmission. Rate 3/4, small memory codes are found which are optimized in the free-distance sense on the Gaussian channel. These codes provide up to 4.8 dB of coding gain with 32 states over uncoded 8-PSK, a scheme having the same spectral efficiency as the codes described. The performance is compared with earlier findings of Ungerboeck and some recent results on R = 2/3 coded 8-PSK. In addition, results of a channel transmission study to assess the performance of the four-state code on the band-limited nonlinear channel are presented, and it is found that performance of the coded scheme degrades comparably with uncoded 8-PSK, i.e., coding gain is roughly preserved.

Wilson, S. G.; Sleeper, H. A.; Schottler, P. J.; Lyons, M. T.

1984-01-01

225

Coset Codes Viewed as Terminated Convolutional Codes  

NASA Technical Reports Server (NTRS)

In this paper, coset codes are considered as terminated convolutional codes. Based on this approach, three new general results are presented. First, it is shown that the iterative squaring construction can equivalently be defined from a convolutional code whose trellis terminates. This convolutional code determines a simple encoder for the coset code considered, and the state and branch labelings of the associated trellis diagram become straightforward. Also, from the generator matrix of the code in its convolutional code form, much information about the trade-off between the state connectivity and complexity at each section, and the parallel structure of the trellis, is directly available. Based on this generator matrix, it is shown that the parallel branches in the trellis diagram of the convolutional code represent the same coset code C(sub 1), of smaller dimension and shorter length. Utilizing this fact, a two-stage optimum trellis decoding method is devised. The first stage decodes C(sub 1), while the second stage decodes the associated convolutional code, using the branch metrics delivered by stage 1. Finally, a bidirectional decoding of each received block starting at both ends is presented. If about the same number of computations is required, this approach remains very attractive from a practical point of view as it roughly doubles the decoding speed. This fact is particularly interesting whenever the second half of the trellis is the mirror image of the first half, since the same decoder can be implemented for both parts.

Fossorier, Marc P. C.; Lin, Shu

1996-01-01

226

Certifying Auto-Generated Flight Code  

NASA Technical Reports Server (NTRS)

Model-based design and automated code generation are being used increasingly at NASA. Many NASA projects now use MathWorks Simulink and Real-Time Workshop for at least some of their modeling and code development. However, there are substantial obstacles to more widespread adoption of code generators in safety-critical domains. Since code generators are typically not qualified, there is no guarantee that their output is correct, and consequently the generated code still needs to be fully tested and certified. Moreover, the regeneration of code can require complete recertification, which offsets many of the advantages of using a generator. Indeed, manual review of autocode can be more challenging than for hand-written code. Since the direct V&V of code generators is too laborious and complicated due to their complex (and often proprietary) nature, we have developed a generator plug-in to support the certification of the auto-generated code. Specifically, the AutoCert tool supports certification by formally verifying that the generated code is free of different safety violations, by constructing an independently verifiable certificate, and by explaining its analysis in a textual form suitable for code reviews. The generated documentation also contains substantial tracing information, allowing users to trace between model, code, documentation, and V&V artifacts. This enables missions to obtain assurance about the safety and reliability of the code without excessive manual V&V effort and, as a consequence, eases the acceptance of code generators in safety-critical contexts. The generation of explicit certificates and textual reports is particularly well-suited to supporting independent V&V. The primary contribution of this approach is the combination of human-friendly documentation with formal analysis. The key technical idea is to exploit the idiomatic nature of auto-generated code in order to automatically infer logical annotations. The annotation inference algorithm itself is generic, and parametrized with respect to a library of coding patterns that depend on the safety policies and the code generator. The patterns characterize the notions of definitions and uses that are specific to the given safety property. For example, for initialization safety, definitions correspond to variable initializations while uses are statements which read a variable, whereas for array bounds safety, definitions are the array declarations, while uses are statements which access an array variable. The inferred annotations are thus highly dependent on the actual program and the properties being proven. The annotations, themselves, need not be trusted, but are crucial to obtain the automatic formal verification of the safety properties without requiring access to the internals of the code generator. The approach has been applied to both in-house and commercial code generators, but is independent of the particular generator used. It is currently being adapted to flight code generated using MathWorks Real-Time Workshop, an automatic code generator that translates from Simulink/Stateflow models into embedded C code.

Denney, Ewen

2008-01-01

227

Fast inter-frame coding with intra skip strategy in H.264 video coding  

Microsoft Academic Search

Inter-frame coding in the H.264\\/AVC standard must address inter modes and intra modes when seeking the best coding mode. Despite achieving a higher coding efficiency than any other previous coding standards, H.264\\/AVC also has a significantly high computation complexity. This investigation, based on the information of the histogram difference and rate part of the rate-distortion optimization in motion estimation, develops

Pei-Jun Lee; Yi-Jie Shih

2009-01-01

228

Partial Dead Code Elimination  

Microsoft Academic Search

A new aggressive algorithm for the elimination of par- tially dead code is presented, i.e., of code which is only dead on some program paths. Besides being more pow- erful than the usual approaches to dead code elimina- tion, this algorithm is optimal in the following sense: partially dead code remaining in the resulting program cannot be eliminated without changing

Jens Knoop; Oliver Rüthing; Bernhard Steffen

1994-01-01

229

Mobile Code Security  

Microsoft Academic Search

Mobile code is an exciting new technology. By its very nature, however, it is fraught withinherent security risks. In the paper, we give an overview of some of the techniques for securingmobile code environments that have been suggested and deployed. We examine the sandboxapproach, code signing, hybrid approaches, firewalling techniques and proof carrying code. Therelative merits of each approach are

Aviel D. Rubin; Daniel E. Geer Jr.

1998-01-01

230

Mobile Code Security Techniques  

Microsoft Academic Search

This paper presents a survey of existing techniques for achieving mobile code security, as well as a representative sampling of systems which use them. In particular, the problem domain is divided into two portions: protecting hosts from malicious code; and protecting mobile code from malicious hosts. The discussion of the malicious code problem includes a more in-depth study of the

Jonathan Moore

1998-01-01

231

Turbo-SPC codes  

Microsoft Academic Search

This letter is concerned with a family of modified turbo-type codes, referred to as turbo-SPC (single parity check) codes. A technique based on the SPC code is introduced to replace puncturing for rate adjustment. A noticeable feature of the proposed scheme is the significantly reduced decoding complexity compared with the standard punctured turbo code. The cost reduction factor becomes more

Li Ping; ENCODING PRINCIPLES

2001-01-01

232

Multiphase Complementary Codes  

Microsoft Academic Search

A new class of complementary codes, similar to the complementary series of Golay but having multiphase elements, have been found to exist with specific complementary aperiodic complex autocorrelation functions. These new codes, called multiphase complementary codes, form a class of generalized complementary codes, of which the Golay complementary series can be considered to be a particular biphase subclass. Unlike Golay

R. Sivaswamy

1978-01-01

233

Robust Distributed Source Coding  

Microsoft Academic Search

We consider a distributed source coding system in which several observations are communicated to the decoder using limited transmission rate. The observations must be separately coded. We introduce a robust distributed coding scheme which flexibly trades off b etween system robustness and compression efficiency. The optimality of this coding scheme is proved fo r various special cases. Index Terms—CEO problem,

Jun Chen; Toby Berger

2006-01-01

234

Subsystem codes with spatially local generators  

SciTech Connect

We study subsystem codes whose gauge group has local generators in two-dimensional (2D) geometry. It is shown that there exists a family of such codes defined on lattices of size LxL with the number of logical qubits k and the minimum distance d both proportional to L. The gauge group of these codes involves only two-qubit generators of type XX and ZZ coupling nearest-neighbor qubits (and some auxiliary one-qubit generators). Our proof is not constructive as it relies on a certain version of the Gilbert-Varshamov bound for classical codes. Along the way, we introduce and study properties of generalized Bacon-Shor codes that might be of independent interest. Secondly, we prove that any 2D subsystem [n,k,d] code with spatially local generators obeys upper bounds kd=O(n) and d{sup 2}=O(n). The analogous upper bound proved recently for 2D stabilizer codes is kd{sup 2}=O(n). Our results thus demonstrate that subsystem codes can be more powerful than stabilizer codes under the spatial locality constraint.

Bravyi, Sergey [IBM T. J. Watson Research Center, Yorktown Heights, New York 10598 (United States)

2011-01-15

235

A generalized interface module for the coupling of spatial kinetics and thermal-hydraulics codes  

Microsoft Academic Search

A generalized interface module has been developed for the coupling of any thermal-hydraulics code to any spatial kinetics code. The coupling scheme was designed and implemented with emphasis placed on maximizing flexibility while minimizing modifications to the respective codes. In this design, the thermal-hydraulics, general interface, and spatial kinetics codes function independently and utilize the Parallel Virtual Machine software to

D. A. Barber; R. M. Miller; H. G. Joo; T. J. Downar; W. Wang; V. A. Mousseau; D. D. Ebert

1999-01-01

236

Linear scalable dispersion codes: signal design and performance analysis  

Microsoft Academic Search

Using Tarokhs criteria for space-time codes, we analyze the design of linear scalable dispersion (LSD) codes. These codes are designed to utilize large numbers of transmit antennas, to exploit high diversity factors and to trade spatial diversity gain for spatial multiplexing gain in a very flexible way. We investigate the diversity and coding gain for Rayleigh fading and show in

Marc Kuhn; I. Hammerstrom; A. Wittneben

2004-01-01

237

Algebraic geometric codes  

NASA Technical Reports Server (NTRS)

The performance characteristics are discussed of certain algebraic geometric codes. Algebraic geometric codes have good minimum distance properties. On many channels they outperform other comparable block codes; therefore, one would expect them eventually to replace some of the block codes used in communications systems. It is suggested that it is unlikely that they will become useful substitutes for the Reed-Solomon codes used by the Deep Space Network in the near future. However, they may be applicable to systems where the signal to noise ratio is sufficiently high so that block codes would be more suitable than convolutional or concatenated codes.

Shahshahani, M.

1991-01-01

238

Application of the MELCOR Code to Design Basis PWR Large Dry Containment Analysis.  

National Technical Information Service (NTIS)

The MELCOR computer code has been developed by Sandia National Laboratories under USNRC sponsorship to provide capability for independently auditing analyses submitted by reactor manufactures and utilities. MELCOR is a fully integrated code (encompassing ...

A. Notafrancesco J. Phillips J. L. Tills

2009-01-01

239

Independent Lens: Interactive  

NSDL National Science Digital Library

Over the past few years, Independent Lens has produced a number of well-received documentaries that have aired on PBS and other places. They have also created some very nice websites in an attempt to enhance the viewing experience of their programs. The Independent Lens: Interactive site offers some additional web-original projects for the interested public. Some of these features include Beyond the Fire, which introduces visitors to the stories of fifteen teenagers living in the US, who have survived war in seven different regions. One very compelling highlight of the site is the Off the Map feature. Here visitors can learn about the visionary art produced by a selection of persons working in various media, such as bottle caps, matchsticks, and chewing gum. For those looking for something with a unique perspective on the world and its inhabitants, this website will definitely bring a smile to their eyes.

2005-01-01

240

ARA type protograph codes  

NASA Technical Reports Server (NTRS)

An apparatus and method for encoding low-density parity check codes. Together with a repeater, an interleaver and an accumulator, the apparatus comprises a precoder, thus forming accumulate-repeat-accumulate (ARA codes). Protographs representing various types of ARA codes, including AR3A, AR4A and ARJA codes, are described. High performance is obtained when compared to the performance of current repeat-accumulate (RA) or irregular-repeat-accumulate (IRA) codes.

Divsalar, Dariush (Inventor); Abbasfar, Aliazam (Inventor); Jones, Christopher R. (Inventor); Dolinar, Samuel J. (Inventor); Thorpe, Jeremy C. (Inventor); Andrews, Kenneth S. (Inventor); Yao, Kung (Inventor)

2008-01-01

241

Independence among People with Disabilities: II. Personal Independence Profile.  

ERIC Educational Resources Information Center

Developed Personal Independence Profile (PIP) as an instrument to measure aspects of independence beyond physical and cognitive functioning in people with diverse disabilities. PIP was tested for reliability and validity with 185 subjects from 10 independent living centers. Findings suggest that the Personal Independence Profile measures the…

Nosek, Margaret A.; And Others

1992-01-01

242

Reusable State Machine Code Generator  

NASA Astrophysics Data System (ADS)

The State Machine model is frequently used to represent the behaviour of a system, allowing one to express and execute this behaviour in a deterministic way. A graphical representation such as a UML State Chart diagram tames the complexity of the system, thus facilitating changes to the model and communication between developers and domain experts. We present a reusable state machine code generator, developed by the Universidad Técnica Federico Santa María and the European Southern Observatory. The generator itself is based on the open source project architecture, and uses UML State Chart models as input. This allows for a modular design and a clean separation between generator and generated code. The generated state machine code has well-defined interfaces that are independent of the implementation artefacts such as the middle-ware. This allows using the generator in the substantially different observatory software of the Atacama Large Millimeter Array and the ESO Very Large Telescope. A project-specific mapping layer for event and transition notification connects the state machine code to its environment, which can be the Common Software of these projects, or any other project. This approach even allows to automatically create tests for a generated state machine, using techniques from software testing, such as path-coverage.

Hoffstadt, A. A.; Reyes, C.; Sommer, H.; Andolfato, L.

2010-12-01

243

Design of network-coding based multi-edge type LDPC codes for a multi-source relaying system  

Microsoft Academic Search

In this paper we investigate a multi-source LDPC coding scheme for a Gaussian relay system, where M sources communicate with the destination under the help of a single relay (M - 1 - 1 system). More specifically, we propose a network coded LDPC coding scheme for the M - 1 - 1 system where network coding over all sources' data

Jun Li; Marwan H. Azmi; Robert Malaney; Jinhong Yuan

2010-01-01

244

Independent verification of radionuclide calculations for selected accident scenarios  

SciTech Connect

An independent verification of the Source Term Code Package (STCP) calculated source terms resulting from severe nuclear reactor accidents is presented. This consists of assessing the modeling options, data transfer, and problem nodalization for both Boiling and Pressurized Water Reactor applications. Independent calculations are also performed for four specific accident scenarios in three different light water reactor containment designs. A detailed review and assessment of the Battelle Columbus Laboratories (BCL) calculated results using the STCP for four reference plants is also made. Comparison of the STCP calculated source terms with the suite of codes as documented in BMI-2104 is also given when applicable.

Cazzoli, E.; Davis, R.; Khatib-Rahbar, M.; Lee, M.; Nourbakhsh, H.; Schmidt, E.; Divadeenam, M.; Davis, R.

1986-07-01

245

Computational Investigation of Subsonic Torsional Airfoil Flutter.  

National Technical Information Service (NTIS)

In this thesis single-degree-of-freedom torsional airfoil flutter is investigated using an incompressible potential flow code, a compressible inviscid Euler code and a compressible viscous Navier-Stokes code. It is found that the classical linearized inco...

C. Kakkavas

1998-01-01

246

Multithread video coding processor for the videophone  

Microsoft Academic Search

The architecture of a programmable video codec IC is described that employs multiple vector processors in a single chip. The vector processors operate in parallel and communicate with one another through on-chip shared memories. A single scaler control processor schedules each vector processor independently to achieve real-time video coding with special vector instructions. With programmable interconnection buses, the proposed architecture

Jeong-Min Kim; Seok-Kyun Hong; Eel-Wan Lee; Soo-Ik Chae

1995-01-01

247

The AMOS (azimuthal mode simulator) code  

Microsoft Academic Search

AMOS, a newly developed computer code that is finding application in the design of accelerator cavities, is described. The program simulates the temporal evolution of electromagnetic fields in rotationally symmetric structures. An explicit Fourier series expansion is assumed in the azimuthal coordinate, which allows different multiple modes to be simulated independently. Nonuniform electrical properties (ε, ?, ?) are permitted, and

J. F. DeFord; G. D. Craig; R. McLeod

1989-01-01

248

Speech coding based upon vector quantization  

Microsoft Academic Search

With rare exception, all presently available narrow-band speech coding systems implement scalar quantization (independent quantization) of the transmission parameters (such as reflection coefficients or transformed reflection coefficients in LPC systems). This paper presents a new approach called vector quantization. For very low data rates, realistic experiments have shown that vector quantization can achieve a given level of average distortion with

ANDRES BUZO; R. Gray; J. Markel

1980-01-01

249

Goppa codes with Weierstrass pairs  

Microsoft Academic Search

We started on a systematic investigation of the Weierstrass pairs on a smooth curve, in our previous papers (Arch. Math. 62 (1994) 73–82); 67 (1996) 337–348. We push our study further for the purpose of constructing Goppa codes with good parameters.

Masaaki Homma; Seon Jeong Kim

2001-01-01

250

INFANTS' CODING OF LOCATION IN CONTINUOUS SPACE  

Microsoft Academic Search

The ability to code location in continuous space is fundamental to spatial behavior. Existing evidence indicates a robust ability for such coding by 12 months, but systematic evidence on earlier origins is lacking. A series of studies investigated 5-month-olds' ability to code the location of an object hidden in a sandbox, using a looking-time paradigm. In Experiment 1, after familiarization

Nora Newcombe; Janellen Huttenlocher

2000-01-01

251

Speaker-independent phone recognition using hidden Markov models  

Microsoft Academic Search

Hidden Markov modeling is extended to speaker-independent phone recognition. Using multiple codebooks of various linear-predictive-coding (LPC) parameters and discrete hidden Markov models (HMMs) the authors obtain a speaker-independent phone recognition accuracy of 58.8-73.8% on the TIMIT database, depending on the type of acoustic and language models used. In comparison, the performance of expert spectrogram readers is only 69% without use

Kai-fu Lee; Hsiao-wuen Hon

1989-01-01

252

Independent Lens: Butte, America  

NSDL National Science Digital Library

Butte, Montana was a hard rock mining town that supplied the United States with much-needed copper, due to the electrification of the nation. The documentary created by Independent Lens of PBS shows the hardship the miners and their families encountered. The Independent Lens website has a multitude of interactive features that adds depth and increased understanding to the film. To find when and on what PBS station the film is playing, visitors can click the link "Check Local Listings". Under the "The Film" tab, three clips of the film are available, and under "The Making of " tab, visitors can find details the difficulties of the film crew in filming the underground mining tunnels. The filmmaker also addresses the challenges of working in 16mm film, and the painful decisions of what scenes to cut. "Related Links" can also be found at the bottom of "The Film" link and provides links to several articles on the town of Butte, as well as to the filmmaker's website.

253

Scalable dope-coded biosensing particles for protein detection  

NASA Astrophysics Data System (ADS)

We present a method to fabricate, assemble dope-coded biosensing particles, and demonstrate a scalable high throughput protein detection application. The coded biosensing particles (8 ?m in diameter and 280 nm thick) are composed of biosensing/coding/magnetic/adhesive layers and coded via patterned boron doping. Coding via doping is powerful in that it can be easily decoded, permits scalability of bit sizes down to tens of nanometers, generates a large number of codes, and retains uniform particle size and shape independent of particle code for consistent protein analysis. Following suspension phase protein binding, the dope-coded biosensing particles are extracted with an external magnet and analyzed with an atomic force microscope.

Ly, Nguyen; Tao, Nongjian

2006-01-01

254

Diagnosis code assignment: models and evaluation metrics  

PubMed Central

Background and objective The volume of healthcare data is growing rapidly with the adoption of health information technology. We focus on automated ICD9 code assignment from discharge summary content and methods for evaluating such assignments. Methods We study ICD9 diagnosis codes and discharge summaries from the publicly available Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC II) repository. We experiment with two coding approaches: one that treats each ICD9 code independently of each other (flat classifier), and one that leverages the hierarchical nature of ICD9 codes into its modeling (hierarchy-based classifier). We propose novel evaluation metrics, which reflect the distances among gold-standard and predicted codes and their locations in the ICD9 tree. Experimental setup, code for modeling, and evaluation scripts are made available to the research community. Results The hierarchy-based classifier outperforms the flat classifier with F-measures of 39.5% and 27.6%, respectively, when trained on 20?533 documents and tested on 2282 documents. While recall is improved at the expense of precision, our novel evaluation metrics show a more refined assessment: for instance, the hierarchy-based classifier identifies the correct sub-tree of gold-standard codes more often than the flat classifier. Error analysis reveals that gold-standard codes are not perfect, and as such the recall and precision are likely underestimated. Conclusions Hierarchy-based classification yields better ICD9 coding than flat classification for MIMIC patients. Automated ICD9 coding is an example of a task for which data and tools can be shared and for which the research community can work together to build on shared models and advance the state of the art.

Perotte, Adler; Pivovarov, Rimma; Natarajan, Karthik; Weiskopf, Nicole; Wood, Frank; Elhadad, Noemie

2014-01-01

255

Description of ground motion data processing codes: Volume 3  

SciTech Connect

Data processing codes developed to process ground motion at the Nevada Test Site for the Weapons Test Seismic Investigations Project are used today as part of the program to process ground motion records for the Nevada Nuclear Waste Storage Investigations Project. The work contained in this report documents and lists codes and verifies the ``PSRV`` code. 39 figs.

Sanders, M.L.

1988-02-01

256

DIANE multiparticle transport code  

NASA Astrophysics Data System (ADS)

DIANE is the general Monte Carlo code developed at CEA-DAM. DIANE is a 3D multiparticle multigroup code. DIANE includes automated biasing techniques and is optimized for massive parallel calculations.

Caillaud, M.; Lemaire, S.; Ménard, S.; Rathouit, P.; Ribes, J. C.; Riz, D.

2014-06-01

257

Cellulases and coding sequences  

DOEpatents

The present invention provides three fungal cellulases, their coding sequences, recombinant DNA molecules comprising the cellulase coding sequences, recombinant host cells and methods for producing same. The present cellulases are from Orpinomyces PC-2.

Li, Xin-Liang (Athens, GA); Ljungdahl, Lars G. (Athens, GA); Chen, Huizhong (Lawrenceville, GA)

2001-02-20

258

Cellulases and coding sequences  

DOEpatents

The present invention provides three fungal cellulases, their coding sequences, recombinant DNA molecules comprising the cellulase coding sequences, recombinant host cells and methods for producing same. The present cellulases are from Orpinomyces PC-2.

Li, Xin-Liang (Athens, GA); Ljungdahl, Lars G. (Athens, GA); Chen, Huizhong (Lawrenceville, GA)

2001-01-01

259

Multiple Turbo Codes  

NASA Technical Reports Server (NTRS)

A description is given of multiple turbo codes and a suitable decoder structure derived from an approximation to the maximum a posteriori probability (MAP) decision rule, which is substantially different from the decoder for two-code-based encoders.

Divsalar, D.; Pollara, F.

1995-01-01

260

On the Rate Loss of Multiterminal Source Codes  

Microsoft Academic Search

In this paper, we study the rate loss and achievable region of the multiterminal source code (MTSC), which is the code designed for a system comprising two independent encoders and joint decoder: encoders 1 and 2 describe sources X and Y using rates R1 and R2 , respectively, and the joint decoder reconstructs X with distortion D1 and reconstructs Y

Hanying Feng

2006-01-01

261

Source Code Plagiarism--A Student Perspective  

ERIC Educational Resources Information Center

This paper considers the problem of source code plagiarism by students within the computing disciplines and reports the results of a survey of students in Computing departments in 18 institutions in the U.K. This survey was designed to investigate how well students understand the concept of source code plagiarism and to discover what, if any,…

Joy, M.; Cosma, G.; Yau, J. Y.-K.; Sinclair, J.

2011-01-01

262

Coding theory adapted to gait perception  

Microsoft Academic Search

Merged F. Restle's coding theory for movement perception with certain aspects of G. Johansson's vector descriptions of movement to investigate the relative perceptual prominence of several kinds of displays of human walkers. Two versions of a coding model are entertained. The 1st considers the results of a demonstration and an experiment in which points of light were mounted in either

James E. Cutting

1981-01-01

263

Error Detection Reliability of LTE CRC Coding  

Microsoft Academic Search

The error detection performance of CRC coding in LTE with general two-level early stopping algorithms for turbo decoding is investigated. Analytical models for the probability of block error and undetected block error at the code block and transport block levels were developed. Simulations were used to verify the model for shorter CRC lengths and block sizes. The analytical models show

Jung-fu Cheng; Havish Koorapaty

2008-01-01

264

Optimum Classification in Subband Coding of Images  

Microsoft Academic Search

This paper investigates the classification technique, applied to subband coding of images, as a way of exploiting the non-stationary nature of image subbands. An algorithm for maximizing the classification gain, is presented. Each subband is optimally classified and the classification map is sent as side information. After optimum rate allocation, the classes are encoded using arithmetic and trellis coded quantization

Rajan L. Joshi; Thomas R. Fischer; Roberto H. Bamberger

1994-01-01

265

Multidimensional Incremental Parsing for Universal Source Coding  

Microsoft Academic Search

A multidimensional incremental parsing algorithm (MDIP) for multidimensional discrete sources, as a generalization of the Lempel-Ziv coding algorithm, is investigated. It consists of three essential component schemes, maximum decimation matching, hierarchical structure of multidimensional source coding, and dictionary augmentation. As a counterpart of the longest match search in the Lempel-Ziv algorithm, two classes of maximum decimation matching are studied. Also,

Soo Hyun Bae; Biing-Hwang Juang

2008-01-01

266

STEEP32 computer code  

NASA Technical Reports Server (NTRS)

A manual is presented as an aid in using the STEEP32 code. The code is the EXEC 8 version of the STEEP code (STEEP is an acronym for shock two-dimensional Eulerian elastic plastic). The major steps in a STEEP32 run are illustrated in a sample problem. There is a detailed discussion of the internal organization of the code, including a description of each subroutine.

Goerke, W. S.

1972-01-01

267

Transparent self-healing communication networks via diversity coding  

Microsoft Academic Search

The authors present an error control based approach, called diversity coding, to provide nearly instantaneous self-healing digital communication networks. This is achieved by constructing an error-correcting code across logically independent channels and by treating link failures within the framework of an erasure channel model. Diversity coding is more efficient than the existing approaches to self-healing communication networks since it is

Chih-Lin I; Ender Ayanoglu; R. D. Gitlin; J. E. Mazo

1990-01-01

268

Welcome to Source Code for Biology and Medicine  

PubMed Central

This editorial introduces Source Code for Biology and Medicine, a new journal for publication of programming source code used in biology and medicine. Source Code for Biology and Medicine is an open access independent journal published by BioMed Central. We describe the journal aims, scope, benefits of open access, article processing charges, competing interests, content and article format, peer review policy and publication, and introduce the Editorial Board.

Peterson, Leif E; Ifeachor, Emmanuel C

2006-01-01

269

Independent Research/Independent Exploratory Development FY86.  

National Technical Information Service (NTIS)

This report provides summaries of FY86 Independent Research (IR) and Independent Exploratory Development (IED) efforts and the IR/IED funding profile, and presentations and publications based on IR/IED efforts. The following IR efforts are described: mode...

A. M. Crawford M. H. Metcalfe

1987-01-01

270

Code Factoring in GCC  

Microsoft Academic Search

Though compilers usually focus on optimizing for performance, the size of the generated code has only received attention recently. On gen- eral desktop systems the code size is not the biggest concern, but on devices with a limited storage capacity compilers should strive for as small a code as possible. GCC already con- tains some very useful algorithms for optimiz-

Gábor Lóki; Ákos Kiss; Judit Jász; Árpád Beszédes

271

The Influence of Building Codes on Recreation Facility Design.  

ERIC Educational Resources Information Center

Implications of building codes upon design and construction of recreation facilities are investigated (national building codes, recreation facility standards, and misperceptions of design requirements). Recreation professionals can influence architectural designers to correct past deficiencies, but they must understand architectural and…

Morrison, Thomas A.

1989-01-01

272

Color code identification in coded structured light.  

PubMed

Color code is widely employed in coded structured light to reconstruct the three-dimensional shape of objects. Before determining the correspondence, a very important step is to identify the color code. Until now, the lack of an effective evaluation standard has hindered the progress in this unsupervised classification. In this paper, we propose a framework based on the benchmark to explore the new frontier. Two basic facets of the color code identification are discussed, including color feature selection and clustering algorithm design. First, we adopt analysis methods to evaluate the performance of different color features, and the order of these color features in the discriminating power is concluded after a large number of experiments. Second, in order to overcome the drawback of K-means, a decision-directed method is introduced to find the initial centroids. Quantitative comparisons affirm that our method is robust with high accuracy, and it can find or closely approach the global peak. PMID:22859022

Zhang, Xu; Li, Youfu; Zhu, Limin

2012-08-01

273

PRINCIPAL AND INDEPENDENT COMPONENT ANALYSIS IN IMAGE PROCESSING  

Microsoft Academic Search

This paper is devoted to practical utilization of Principal Component Analysis (PCA) and its extension Independent Component Analysis (ICA). Our inten- sion is to demonstrate different applications of the above mentioned methods in biomedical image and signal processing. The concept of ICA in terms of blind source separation is illustrated on EEG signals, whereas the approach of sparse coding is

S. Vaseghi; H. Jetelova

274

Source Code Library  

NSDL National Science Digital Library

At the DevX Source Code Library and the newer Sourcebank, users can download source code, algorithms, and sample applications. The Library is culled from DevX services and magazines, and resources are grouped into browseable and searchable categories. The Sourcebank collects code and related tools from sites around the Web and also is searchable and browseable. Users can limit their browsing by type of resource as well (Perl code, Java code, research papers, etc.). Perhaps needless to say, file formats are too numerous to name here.

1969-12-31

275

Multiple-User Cooperative Communications Based on Linear Network Coding  

Microsoft Academic Search

We propose a new scheme for cooperative wireless networking based on linear network codes. The network consists of multiple (M ? 2) users having independent information to be transmitted to a common basestation (BS), assuming block-fading channels with independent fading for different codewords. The users collaborate in relaying messages. Because of potential transmission errors in links, resulting in erasures, the

Ming Xiao; Mikael Skoglund

2010-01-01

276

Independent Component Analysis Blind Beamformer.  

National Technical Information Service (NTIS)

Independent Component Analysis (ICA) has been proven to be a very successful method for separating mixed signals blindly. ICA works by using the assumption that signal mixtures are combinations of independent signals. Up to now, ICA has been primarily use...

M. L. Salerno

2000-01-01

277

The National Transport Code Collaboration Module Library  

NASA Astrophysics Data System (ADS)

This paper reports on the progress in developing a library of code modules under the auspices of the National Transport Code Collaboration (NTCC). Code modules are high quality, fully documented software packages with a clearly defined interface. The modules provide a variety of functions, such as implementing numerical physics models; performing ancillary functions such as I/O or graphics; or providing tools for dealing with common issues in scientific programming such as portability of Fortran codes. Researchers in the plasma community submit code modules, and a review procedure is followed to insure adherence to programming and documentation standards. The review process is designed to provide added confidence with regard to the use of the modules and to allow users and independent reviews to validate the claims of the modules' authors. All modules include source code; clear instructions for compilation of binaries on a variety of target architectures; and test cases with well-documented input and output. All the NTCC modules and ancillary information, such as current standards and documentation, are available from the NTCC Module Library Website http://w3.pppl.gov/NTCC. The goal of the project is to develop a resource of value to builders of integrated modeling codes and to plasma physics researchers generally. Currently, there are more than 40 modules in the module library.

Kritz, A. H.; Bateman, G.; Kinsey, J.; Pankin, A.; Onjun, T.; Redd, A.; McCune, D.; Ludescher, C.; Pletzer, A.; Andre, R.; Zakharov, L.; Lodestro, L.; Pearlstein, L. D.; Jong, R.; Houlberg, W.; Strand, P.; Wiley, J.; Valanju, P.; John, H. St.; Waltz, R.; Mandrekas, J.; Mau, T. K.; Carlsson, J.; Braams, B.

2004-12-01

278

Logical independence in quantum logic  

Microsoft Academic Search

The projection latticesP(1),P(2) of two von Neumann subalgebras 1, 2 of the von Neumann algebra are defined to be logically independent if A B0 for any 0AP(1), 0BP(2). After motivating this notion in independence, it is shown thatP(1),P(2) are logically independent if 1 is a subfactor in a finite factor andP(1),P(2 commute. Also, logical independence is related to the statistical

Miklós Rédei

1995-01-01

279

Independent Lens Strange Fruit  

NSDL National Science Digital Library

The accompanying website for the Independent Lens film "Strange Fruit", about the famous protest song, allows visitors to hear a clip, or the entire song, of a famous rendition sung Billie Holiday. Strange Fruit is a phrase that actually comes from a poem that was turned into a song, and the song became the most renowned protest song of the 1940s. Visitors unfamiliar with the song will find that the link, "The Film", on the homepage gives an informative several paragraph synopsis and history. It also explains the unusual turns the life of the poet/songwriter took. Visitors should not miss the "Protest Music Overview" link, which provides clips of other protest songs. These protest songs are grouped by time period and the topic of protest for the period. Visitors should start at the beginning with 1776 and slavery, and then just wander through the centuries of music. Some of the clips featured within the different time periods include "Fight The Power" by Public Enemy, "Ohio" by Neil Young, and "We Shall Overcome" sung by Mahalia Jackson.

280

Independents' group posts loss  

SciTech Connect

Low oil gas prices and special charges caused the group of 50 U.S. independent producers Oil and Gas Journal tracks to post a combined loss in first half 1992. The group logged a net loss of $53 million in the first half compared with net earnings of $354 million in first half 1991, when higher oil prices during the Persian Gulf crisis buoyed earnings in spite of crude oil and natural gas production declines. The combined loss in the first half follows a 45% drop in the group's earnings in 1991 and compares with the OGJ group of integrated oil companies whose first half 1992 income fell 47% from the prior year. Special charges, generally related to asset writedowns, accounted for most of the almost $560 million in losses posted by about the third of the group. Nerco Oil and Gas Inc., Vancouver, Wash., alone accounted for almost half that total with charges related to an asset writedown of $238 million in the first quarter. Despite the poor first half performance, the outlook is bright for sharply improved group earnings in the second half, assuming reasonably healthy oil and gas prices and increased production resulting from acquisitions and in response to those prices.

Sanders, V.; Price, R.B.

1992-11-23

281

Studying the Independent School Library  

ERIC Educational Resources Information Center

In 2005, the American Association of School Librarians' Independent Schools Section conducted a national survey of independent school libraries. This article analyzes the results of the survey, reporting specialized data and information regarding independent school library budgets, collections, services, facilities, and staffing. Additionally, the…

Cahoy, Ellysa Stern; Williamson, Susan G.

2008-01-01

282

Melanism in Peromyscus Is Caused by Independent Mutations in Agouti  

PubMed Central

Identifying the molecular basis of phenotypes that have evolved independently can provide insight into the ways genetic and developmental constraints influence the maintenance of phenotypic diversity. Melanic (darkly pigmented) phenotypes in mammals provide a potent system in which to study the genetic basis of naturally occurring mutant phenotypes because melanism occurs in many mammals, and the mammalian pigmentation pathway is well understood. Spontaneous alleles of a few key pigmentation loci are known to cause melanism in domestic or laboratory populations of mammals, but in natural populations, mutations at one gene, the melanocortin-1 receptor (Mc1r), have been implicated in the vast majority of cases, possibly due to its minimal pleiotropic effects. To investigate whether mutations in this or other genes cause melanism in the wild, we investigated the genetic basis of melanism in the rodent genus Peromyscus, in which melanic mice have been reported in several populations. We focused on two genes known to cause melanism in other taxa, Mc1r and its antagonist, the agouti signaling protein (Agouti). While variation in the Mc1r coding region does not correlate with melanism in any population, in a New Hampshire population, we find that a 125-kb deletion, which includes the upstream regulatory region and exons 1 and 2 of Agouti, results in a loss of Agouti expression and is perfectly associated with melanic color. In a second population from Alaska, we find that a premature stop codon in exon 3 of Agouti is associated with a similar melanic phenotype. These results show that melanism has evolved independently in these populations through mutations in the same gene, and suggest that melanism produced by mutations in genes other than Mc1r may be more common than previously thought.

Kingsley, Evan P.; Manceau, Marie; Wiley, Christopher D.; Hoekstra, Hopi E.

2009-01-01

283

Modular optimization code package: MOZAIK  

NASA Astrophysics Data System (ADS)

This dissertation addresses the development of a modular optimization code package, MOZAIK, for geometric shape optimization problems in nuclear engineering applications. MOZAIK's first mission, determining the optimal shape of the D2O moderator tank for the current and new beam tube configurations for the Penn State Breazeale Reactor's (PSBR) beam port facility, is used to demonstrate its capabilities and test its performance. MOZAIK was designed as a modular optimization sequence including three primary independent modules: the initializer, the physics and the optimizer, each having a specific task. By using fixed interface blocks among the modules, the code attains its two most important characteristics: generic form and modularity. The benefit of this modular structure is that the contents of the modules can be switched depending on the requirements of accuracy, computational efficiency, or compatibility with the other modules. Oak Ridge National Laboratory's discrete ordinates transport code TORT was selected as the transport solver in the physics module of MOZAIK, and two different optimizers, Min-max and Genetic Algorithms (GA), were implemented in the optimizer module of the code package. A distributed memory parallelism was also applied to MOZAIK via MPI (Message Passing Interface) to execute the physics module concurrently on a number of processors for various states in the same search. Moreover, dynamic scheduling was enabled to enhance load balance among the processors while running MOZAIK's physics module thus improving the parallel speedup and efficiency. In this way, the total computation time consumed by the physics module is reduced by a factor close to M, where M is the number of processors. This capability also encourages the use of MOZAIK for shape optimization problems in nuclear applications because many traditional codes related to radiation transport do not have parallel execution capability. A set of computational models based on the existing beam port configuration of the Penn State Breazeale Reactor (PSBR) was designed to test and validate the code package in its entirety, as well as its modules separately. The selected physics code, TORT, and the requisite data such as source distribution, cross-sections, and angular quadratures were comprehensively tested with these computational models. The modular feature and the parallel performance of the code package were also examined using these computational models. Another outcome of these computational models is to provide the necessary background information for determining the optimal shape of the D2O moderator tank for the new beam tube configurations for the PSBR's beam port facility. The first mission of the code package was completed successfully by determining the optimal tank shape which was sought for the current beam tube configuration and two new beam tube configurations for the PSBR's beam port facility. The performance of the new beam tube configurations and the current beam tube configuration were evaluated with the new optimal tank shapes determined by MOZAIK. Furthermore, the performance of the code package with the two different optimization strategies were analyzed showing that while GA is capable of achieving higher thermal beam intensity for a given beam tube setup, Min-max produces an optimal shape that is more amenable to machining and manufacturing. The optimal D2O moderator tank shape determined by MOZAIK with the current beam port configuration improves the thermal neutron beam intensity at the beam port exit end by 9.5%. Similarly, the new tangential beam port configuration (beam port near the core interface) with the optimal moderator tank shape determined by MOZAIK improves the thermal neutron beam intensity by a factor of 1.4 compared to the existing beam port configuration (with the existing D2O moderator tank). Another new beam port configuration, radial beam tube configuration, with the optimal moderator tank shape increases the thermal neutron beam intensity at the beam tube exit by a factor of 1.8. All these results

Bekar, Kursat B.

284

Codes and coding processes in pigeon short-term memory  

Microsoft Academic Search

The delayed matching-to-sample (DMTS) task was used in three experiments to investigate how pigeons code information about\\u000a sample stimuli. In all experiments, each trial consisted of a signaled presentation of a sample stimulus for a fixed duration\\u000a followed, after some delay, by the presentation of three comparison stimuli. After incorrect first choices, the bird was allowed\\u000a a second choice between

H. L. Roitblat

1980-01-01

285

Animal Behavior: An Independent Research Project  

NSDL National Science Digital Library

This is an independent research project intended for second semester high school biology students. It could easily be modified for any age life science students. The purpose of the project is to allow students to conduct their own animal behavior research investigation, from beginning to end. The process models the way animal research is conducted by research scientists.

Ms. Jeannie Wenndorf (Lindbergh High School)

1997-07-01

286

Permutation Independent Comparison of Pseudo Boolean Functions  

Microsoft Academic Search

We address the problem of permutation independent comparison of two pseudo Boolean functions given by multiplicative binary moment diagrams ( Bmds), i. e., the problem of deciding whether there exists a permutation of the input variables such that the two Bmds are equal. The analogous problem has already been investigated for binary decision diagrams (Bdds) in detail (5, 7, 8,

Riccardo Forth; Paul Molitor

1999-01-01

287

Who Succeeds in an Independent, Open Laboratory?  

ERIC Educational Resources Information Center

This paper reports a study which investigated student characteristics for predicting success in an independent, open laboratory. Data were gathered from introductory biology students (N=98) enrolled in a public, two-year college near Atlanta, Georgia. Stepwise multiple regression analysis was used to determine the effects of age, sex, laboratory…

Halyard, Rebecca A.; And Others

288

Hedgehog Signalling in Androgen Independent Prostate Cancer  

Microsoft Academic Search

Objectives: Androgen-deprivation therapy effectively shrinks hormone- naive prostate cancer, both in the prostate and at sites of distant metastasis. However prolonged androgen deprivation generally results in relapse and androgen-independent tumour growth, which is inevitably fatal. The molec- ular events that enable prostate cancer cells to proliferate in reduced andro- gen conditions are poorly understood. Here we investigate the role of

Greg Shaw; Anna M. Price; Elena Ktori; Isabelle Bisson; Patricia E. Purkis; Siobhan McFaul; R. Tim; D. Oliver; David M. Prowse

289

The Influence of Board Independence, Competency and Ownership on Earnings Management in Malaysia  

Microsoft Academic Search

This paper examines the roles of independent members on the board, chief executive officer who also serves as a chairman of the company, board competency and management's share ownership on earnings management practices. Different from prior research, it also investigates whether independent board competency (an interaction of independence and competency) and independent board share ownership (an interaction of independence and

HASHIMAH JOHARI; MOHD SALEH; SABRI HASSAN

2008-01-01

290

Clinical Reasoning of Physical Therapists regarding In-hospital Walking Independence of Patients with Hemiplegia  

PubMed Central

[Purpose] Physical therapists must often determine whether hemiparetic patients can walk independently. However, there are no criteria, so decisions are often left to individual physical therapists. The purpose of this study was to explore how physical therapists determine whether a patient with hemiplegia can walk independently in a ward. [Methods] The subjects were 15 physical therapists with experience of stroke patients’ rehabilitation. We interviewed them using semi-structured interviews related to the criteria of the states of walking in the ward of hemiparetic patients. The interviews were transcribed in full, and the texts were analyzed by coding and grouping. [Results] From the results of the interviews, PTs determined patients’ independence of walking in hospital by observation of behavior during walking or treatment. The majority of PTs focused on the patients’ state during walking, higher brain function, and their ability to balance. In addition, they often asked ward staff about patients’ daily life, and self-determination. [Conclusions] We identified the items examined by physical therapists when determining the in-hospital walking independence of stroke patients. Further investigation is required to examine which of these items are truly necessary.

Takahashi, Junpei; Takami, Akiyoshi; Wakayama, Saichi

2014-01-01

291

Combinatorial Properties for Traceability Codes Using Error Correcting Codes  

Microsoft Academic Search

In this correspondence, the combinatorial properties of traceability codes constructed from error-correcting codes are studied. Necessary and sufficient conditions for traceability codes constructed from maximum-distance separable (MDS) codes are provided. The known sufficient conditions for a traceability code are proven to be also necessary for linear MDS codes

Hongxia Jin; Mario Blaum

2007-01-01

292

Improved codes for space-time trellis-coded modulation  

Microsoft Academic Search

Space-Time Coded Modulation has been shown to eciently use transmit diversity to increase spectral efficiency. In this letter we propose new trellis codes found through systematic code search. These codes achieve the theoretically maximal diversity gain and improved coding gain compared to known codes.

Stephan Bäro; Gerhard Bauch; Axel Hansmann

2000-01-01

293

Generating code adapted for interlinking legacy scalar code and extended vector code  

DOEpatents

Mechanisms for intermixing code are provided. Source code is received for compilation using an extended Application Binary Interface (ABI) that extends a legacy ABI and uses a different register configuration than the legacy ABI. First compiled code is generated based on the source code, the first compiled code comprising code for accommodating the difference in register configurations used by the extended ABI and the legacy ABI. The first compiled code and second compiled code are intermixed to generate intermixed code, the second compiled code being compiled code that uses the legacy ABI. The intermixed code comprises at least one call instruction that is one of a call from the first compiled code to the second compiled code or a call from the second compiled code to the first compiled code. The code for accommodating the difference in register configurations is associated with the at least one call instruction.

Gschwind, Michael K

2013-06-04

294

P-code enhanced method for processing encrypted GPS signals without knowledge of the encryption code  

NASA Technical Reports Server (NTRS)

In the preferred embodiment, an encrypted GPS signal is down-converted from RF to baseband to generate two quadrature components for each RF signal (L1 and L2). Separately and independently for each RF signal and each quadrature component, the four down-converted signals are counter-rotated with a respective model phase, correlated with a respective model P code, and then successively summed and dumped over presum intervals substantially coincident with chips of the respective encryption code. Without knowledge of the encryption-code signs, the effect of encryption-code sign flips is then substantially reduced by selected combinations of the resulting presums between associated quadrature components for each RF signal, separately and independently for the L1 and L2 signals. The resulting combined presums are then summed and dumped over longer intervals and further processed to extract amplitude, phase and delay for each RF signal. Precision of the resulting phase and delay values is approximately four times better than that obtained from straight cross-correlation of L1 and L2. This improved method provides the following options: separate and independent tracking of the L1-Y and L2-Y channels; separate and independent measurement of amplitude, phase and delay L1-Y channel; and removal of the half-cycle ambiguity in L1-Y and L2-Y carrier phase.

Meehan, Thomas K. (Inventor); Thomas, Jr., Jess Brooks (Inventor); Young, Lawrence E. (Inventor)

2000-01-01

295

Independent Assessment of the Natural-Circulation Capability of the Heterogeneous-Core CRBR.  

National Technical Information Service (NTIS)

This summary describes results of an independent assessment of the natural circulation capability of the heterogeneous core Clinch River Breeder Reactor Plant (CRBRP) following station blackout. The primary tool for this analysis is the Super System Code ...

J. G. Guppy W. C. Horak G. J. Van Tuyle

1983-01-01

296

Mechanical code comparator  

DOEpatents

A new class of mechanical code comparators is described which have broad potential for application in safety, surety, and security applications. These devices can be implemented as micro-scale electromechanical systems that isolate a secure or otherwise controlled device until an access code is entered. This access code is converted into a series of mechanical inputs to the mechanical code comparator, which compares the access code to a pre-input combination, entered previously into the mechanical code comparator by an operator at the system security control point. These devices provide extremely high levels of robust security. Being totally mechanical in operation, an access control system properly based on such devices cannot be circumvented by software attack alone.

Peter, Frank J. (Albuquerque, NM); Dalton, Larry J. (Bernalillo, NM); Plummer, David W. (Albuquerque, NM)

2002-01-01

297

Experimental evaluation of photoacoustic coded excitation using unipolar golay codes.  

PubMed

Q-switched Nd:YAG lasers are commonly used as light sources for photoacoustic imaging. However, laser diodes are attractive as an alternative to Nd:YAG lasers because they are less expensive and more compact. Although laser diodes deliver about three orders of magnitude less light pulse energy than Nd:YAG lasers (tens of microjoules compared with tens of millijoules), their pulse repetition frequency (PRF) is four to five orders of magnitude higher (up to 1 MHz compared with tens of hertz); this enables the use of averaging to improve SNR without compromising the image acquisition rate. In photoacoustic imaging, the PRF is limited by the maximum acoustic time-of-flight. This limit can be overcome by using coded excitation schemes in which the coding eliminates ambiguities between echoes induced by subsequent pulses. To evaluate the benefits of photoacoustic coded excitation (PACE), the performance of unipolar Golay codes is investigated analytically and validated experimentally. PACE imaging of a copper slab using laser diodes at a PRF of 1 MHz and a modified clinical ultrasound scanner is successfully demonstrated. Considering laser safety regulations and taking into account a comparison between a laser diode system and Nd:YAG systems with respect to SNR, we conclude that PACE is feasible for small animal imaging. PMID:20639152

Mienkina, Martin P; Friedrich, Claus-Stefan; Gerhardt, Nils C; Wilkening, Wilko G; Hofmann, Martin R; Schmitz, Georg

2010-07-01

298

Performance of concatenated Reed-Solomon trellis-coded modulation over Rician fading channels  

NASA Technical Reports Server (NTRS)

A concatenated coding scheme for providing very reliable data over mobile-satellite channels at power levels similar to those used for vocoded speech is described. The outer code is a shorter Reed-Solomon code which provides error detection as well as error correction capabilities. The inner code is a 1-D 8-state trellis code applied independently to both the inphase and quadrature channels. To achieve the full error correction potential of this inner code, the code symbols are multiplexed with a pilot sequence which is used to provide dynamic channel estimation and coherent detection. The implementation structure of this scheme is discussed and its performance is estimated.

Moher, Michael L.; Lodge, John H.

1990-01-01

299

United States Code  

NSDL National Science Digital Library

Every six years, the Office of the Law Revision Counsel, US House of Representatives, publishes the United States Code, the "codification of the general and permanent laws of the United States." The first seven titles of the 2000 code have been made available this month at GPO Access. The code can be browsed and searched, and search results include citations plus links to the full text of the legislation.

2001-01-01

300

Industrial Computer Codes  

NASA Technical Reports Server (NTRS)

This is an overview of new and updated industrial codes for seal design and testing. GCYLT (gas cylindrical seals -- turbulent), SPIRALI (spiral-groove seals -- incompressible), KTK (knife to knife) Labyrinth Seal Code, and DYSEAL (dynamic seal analysis) are covered. CGYLT uses G-factors for Poiseuille and Couette turbulence coefficients. SPIRALI is updated to include turbulence and inertia, but maintains the narrow groove theory. KTK labyrinth seal code handles straight or stepped seals. And DYSEAL provides dynamics for the seal geometry.

Shapiro, Wilbur

1996-01-01

301

Scalable Hyperspectral Image Coding  

Microsoft Academic Search

Here we propose scalable Three-Dimensional Set Partitioned Embedded bloCK (3D-SPECK)–an embedded, block-based, wavelet transform coding algorithm of low complexity for hyperspectral image compression. Scalable 3D-SPECK supports both SNR and resolution progressive coding. After wavelet transform, 3D-SPECK treats each subband as a coding block. To generate SNR scalable bitstream, the stream is organized so that the same indexed bit planes are

Xiaoli Tang; William A. Pearlman

2005-01-01

302

Building Codes and Standards  

NSDL National Science Digital Library

This brief document from David Cohan includes some information on building codes and standards. The purpose of building codes and standards is defined, and how they relate to energy and sustainability topics is also explored. This document would be useful for instructors looking for some notes on how to incorporate building codes and standards into their class work, or for students looking to learn more about the topic. This document may be downloaded in PDF file format.

Cohan, David

2012-01-17

303

Codes of Ethics Online  

NSDL National Science Digital Library

The Center for the Study of Ethics in the Professions at the Illinois Institute of Technology maintains the Codes of Ethics Online Web site. The Center writes: "With the advent of the Internet, it seemed clear that digitizing the codes and making them accessible over the World-Wide Web would benefit researchers, students, and professionals alike." The science page contains links to over fifty organizations' ethical codes, including the American Institute of Chemists, the American Physical Society, the Water Quality Association, etc.

304

Compiling esterel intosequential code  

Microsoft Academic Search

Embedded real-time software systems often need fine-grained parallelism and precise control over time, things typical real-time operating systems do not provide. The Esterel language has both, but Existing compilers produce slow code for large programs. This paper presents the first Esterel compiler able to produce small, fast code for large programs. It can produce code half the size and up

Stephen A. Edwards

2000-01-01

305

Resistor Color-Code  

NSDL National Science Digital Library

"Resistor manufactures implement the standard EIA color-code using three, four and five color bands to identify nominal resistor values. It is imperative that engineers and technicians know how to interpret the color markings on resistors in order to perform analysis and repairs on electronic products." On this page, visitors will find a key to the code for three, four, and five band resistors and exercises to check for understanding. A Resistor Color-Code chart can also be downloaded and printed from this site, as well as a Resistor Color-Code Converter.

2011-07-19

306

Laser propagation code study  

NASA Astrophysics Data System (ADS)

A number of laser propagation codes have been assessed as to their suitability for modeling Army High Energy Laser (HEL) weapons used in an anti-sensor mode. A number of areas in which systems analysis HEL codes are deficient are identified. Most notably, available HEL scaling law codes model the laser aperture as circular, possibly with a fixed (e.g., 10%) obscuration. However, most HELs have rectangular apertures with up to 30% obscuration. A beam-quality/aperture shape scaling relation which can be useful when applying these codes to realistic designs for HELs is presented.

Rockower, E. B.

1985-09-01

307

Bar Code Labels  

NASA Technical Reports Server (NTRS)

American Bar Codes, Inc. developed special bar code labels for inventory control of space shuttle parts and other space system components. ABC labels are made in a company-developed anodizing aluminum process and consecutively marketed with bar code symbology and human readable numbers. They offer extreme abrasion resistance and indefinite resistance to ultraviolet radiation, capable of withstanding 700 degree temperatures without deterioration and up to 1400 degrees with special designs. They offer high resistance to salt spray, cleaning fluids and mild acids. ABC is now producing these bar code labels commercially or industrial customers who also need labels to resist harsh environments.

1988-01-01

308

Message Authentication Code  

NSDL National Science Digital Library

This lecture studies message authentication: limitations of cryptographic algorithms in protecting data integrity and supporting message authentication; the design of Message Authentication Code (MAC)

Xue, Yuan

2009-02-14

309

States on Symmetric Logics: Conditional Probability and Independence. II  

NASA Astrophysics Data System (ADS)

We study the notions of conditional probabilities, independence and ?-independence for states on symmetric logics. We prove that a non-atomic state on the logic with the Lyapunov's property is determined by its specification of independent events. We present the examples of (1) ?-subadditive but is not subadditive and (2) two-valued non ?-subadditive states on symmetric logic. We investigate the independence relation transitivity for a ?-subadditive state. We also study continuity properties of conditional probabilities and ?-independence relation with respect to natural pseudometric for ?-subadditive state. Finally, we pose two open problems.

Bikchentaev, Airat; Yakushev, Rinat

2013-09-01

310

Radio Losses for Concatenated Codes  

NASA Astrophysics Data System (ADS)

The advent of higher powered spacecraft amplifiers and better ground receivers capable of tracking spacecraft carrier signals with narrower loop bandwidths requires better understanding of the carrier tracking loss (radio loss) mechanism of the concatenated codes used for deep-space missions. In this article, we present results of simulations performed for a (7,1/2), Reed-Solomon (255,223), interleaver depth-5 concatenated code in order to shed some light on this issue. Through these simulations, we obtained the performance of this code over an additive white Gaussian noise (AWGN) channel (the baseline performance) in terms of both its frame-error rate (FER) and its bit-error rate at the output of the Reed-Solomon decoder (RS-BER). After obtaining these results, we curve fitted the baseline performance curves for FER and RS-BER and calculated the high-rate radio losses for this code for an FER of 10^(-4) and its corresponding baseline RS-BER of 2.1 x 10^(-6) for a carrier loop signal-to-noise ratio (SNR) of 14.8 dB. This calculation revealed that even though over the AWGN channel the FER value and the RS-BER value correspond to each other (i.e., these values are obtained by the same bit SNR value), the RS-BER value has higher high-rate losses than does the FER value. Furthermore, this calculation contradicted the previous assumption th at at high data rates concatenated codes have the same radio losses as their constituent convolutional codes. Our results showed much higher losses for the FER and the RS-BER (by as much as 2 dB) than for the corresponding baseline BER of the convolutional code. Further simulations were performed to investigate the effects of changes in the data rate on the code's radio losses. It was observed that as the data rate increased the radio losses for both the FER and the RS-BER approached their respective calculated high-rate values. Furthermore, these simulations showed that a simple two-parameter function could model the increase in the radio losses as the data rate increased for both the FER and the RS-BER. However, further simulations are required to obtain functions for the two parameters in terms of the loop SNR and the error rate for which the loss is calculated.

Shambayati, S.

2002-07-01

311

A robust low-rate coding scheme for packet video  

NASA Technical Reports Server (NTRS)

Due to the rapidly evolving field of image processing and networking, video information promises to be an important part of telecommunication systems. Although up to now video transmission has been transported mainly over circuit-switched networks, it is likely that packet-switched networks will dominate the communication world in the near future. Asynchronous transfer mode (ATM) techniques in broadband-ISDN can provide a flexible, independent and high performance environment for video communication. For this paper, the network simulator was used only as a channel in this simulation. Mixture blocking coding with progressive transmission (MBCPT) has been investigated for use over packet networks and has been found to provide high compression rate with good visual performance, robustness to packet loss, tractable integration with network mechanics and simplicity in parallel implementation.

Chen, Y. C.; Sayood, Khalid; Nelson, D. J.; Arikan, E. (editor)

1991-01-01

312

A code in the protein coding genes  

Microsoft Academic Search

A statistical analysis with 12 288 autocorrelation functions applied in protein (coding) genes of prokaryotes and eukaryotes identifies three subsets of trinucleotides in their three frames: T0 X0@ {AAA, TTT} with X0 {AAC, AAT, ACC, ATC, ATT, CAG, CTC, CTG, GAA, GAC, GAG, GAT, GCC, GGC, GGT, GTA, GTC, GTT, TAC, TTC} in frame 0 (the reading frame established by

Didier G. Arques; Christian J. Michel

1997-01-01

313

Error-correcting codes for flash coding  

Microsoft Academic Search

Flash memory is a non-volatile computer storage device which consists of blocks of cells. While increasing the voltage level of a single cell is fast and simple, reducing the level of a cell requires the erasing of the entire block containing the cell. Since block-erasures are costly, traditional flash coding schemes have been developed to maximize the number of writes

Qin Huang; Shu Lin; Khaled Abdel-Ghaffar

2011-01-01

314

Interleaving of Reed-Solomon Viterbi concatenated coding channel  

NASA Technical Reports Server (NTRS)

Two interleaving schemes are presented for R-S Viterbi concatenated coding channels and several R-S code array synchronization configurations are investigated. A procedure for obtaining synchronization sequences for the R-S code array under specified conditions is developed and used to identify sequences with desirable properties. The two interleaving schemes are found to be comparable in terms of array synchronization.

Chu, C.; Miller, W. H.

1978-01-01

315

Cascaded Coding Scheme for Error Control and Its Performance Analysis.  

National Technical Information Service (NTIS)

A coding scheme for error control in data communication systems is investigated. The scheme is obtained by cascading two error correcting codes, called the inner and the outer codes. The error performance of the scheme is analyzed for a binary symmetric c...

S. Lin

1986-01-01

316

Design of an improved transmission\\/data processing code  

Microsoft Academic Search

Historically there has been strong difference of opinion in the construction of 6-bit (64-character) data codes, based upon whether the code is to be used for communications or data processing. This paper reports on investigation of an improved code which meets transmission requirements and requires very little modification for varied data processing usage.

Robert W. Bemer; H. J. Smith Jr.; Francis A. Williams

1961-01-01

317

Distributed transform coding via source-splitting  

NASA Astrophysics Data System (ADS)

Transform coding (TC) is one of the best known practical methods for quantizing high-dimensional vectors. In this article, a practical approach to distributed TC of jointly Gaussian vectors is presented. This approach, referred to as source-split distributed transform coding (SP-DTC), can be used to easily implement two terminal transform codes for any given rate-pair. The main idea is to apply source-splitting using orthogonal-transforms, so that only Wyner-Ziv (WZ) quantizers are required for compression of transform coefficients. This approach however requires optimizing the bit allocation among dependent sets of WZ quantizers. In order to solve this problem, a low-complexity tree-search algorithm based on analytical models for transform coefficient quantization is developed. A rate-distortion (RD) analysis of SP-DTCs for jointly Gaussian sources is presented, which indicates that these codes can significantly outperform the practical alternative of independent TC of each source, whenever there is a strong correlation between the sources. For practical implementation of SP-DTCs, the idea of using conditional entropy constrained (CEC) quantizers followed by Slepian-Wolf coding is explored. Experimental results obtained with SP-DTC designs based on both CEC scalar quantizers and CEC trellis-coded quantizers demonstrate that actual implementations of SP-DTCs can achieve RD performance close to the analytically predicted limits.

Yahampath, Pradeepa

2012-12-01

318

Auto-blocking matrix-multiplication or tracking BLAS3 performance from source code  

Microsoft Academic Search

An elementary, machine-independent, recursive algorithm for matrix multiplication C+=A*B provides implicit blocking at every level of the memory hierarchy and tests out faster than classically optimrd code, tracking hand-coded BLAS3 routines. Proof of concept is demonstrated by racing the in-place algorithm against manufacturer's hand-tuned BLAS3 routines; it can win.The recursive code bifurcates naturally at the top level into independent block-oriented

Jeremy D. Frens; David S. Wise

1997-01-01

319

Independent Research and Independent Exploratory Development FY 85.  

National Technical Information Service (NTIS)

This report provides summaries of FY85 Independent Research (IR) and Independent Exploratory Development (IED) efforts and the IR/IED funding profile, as well as IR/IED funding profile, as well as IR/IED researchers' awards and honors for FY85 and present...

R. Penn A. Crawford

1986-01-01

320

TRAC-PF1\\/MOD1 independent assessment: NEPTUNUS pressurizer test Y05. [PWR  

Microsoft Academic Search

The TRAC independent assessment project at Sandia National Laboratories is part of an overall effort funded by the NRC to determine the capability of various system codes to predict the detailed thermal\\/hydraulic response of light water reactors during accident and off-normal conditions. The TRAC computer code is being assessed at SNLA against test data from various integral and separate effects

1984-01-01

321

MHDust: A 3-fluid dusty plasma code  

NASA Astrophysics Data System (ADS)

MHDust is a next generation 3-fluid magnetized dusty plasma code, treating the inertial dynamics of both the dust and ion components. Coded in ANSI C, the numerical method employs Leap-Frog and Dufort-Frankel integration schemes. Features include: nonlinear collisional terms, quasi-neutrality or continuity based electron densities, and dynamical dust charge number. Tests of wave-mode propagation (Acoustic and Electromagnetic) allow a comparison to linear wave mode theory. Additional nonlinear phenomena are presented including magnetic reconnection and shear-flow instabilities. Relevant parameters for the space environment are considered, allowing a comparison to be made with previous dusty plasma codes (DENISIS). The utility of the code is expanded through the possibility of small dust mass. This allows MH- Dust to be used as a 2-ion plasma code. MHDust considerably expands the range of numerical investigations into nonlinear phenomena in the field of astrophysical dusty plasmas.

Lazerson, Samuel

322

Hadamard transform image coding  

Microsoft Academic Search

The introduction of the fast Fourier transform algorithm has led to the development of the Fourier transform image coding technique whereby the two-dimensional Fourier transform of an image is transmitted over a channel rather than the image itself. This devlopement has further led to a related image coding technique in which an image is transformed by a Hadamard matrix operator.

W. K. Pratt; J. Kane; H. C. Andrews

1969-01-01

323

Laser Propagation Code Study.  

National Technical Information Service (NTIS)

A number of laser propagation codes have been assessed as to their suitability for modeling Army High Energy Laser (HEL) weapons used in an anti-sensor mode. We identify a number of areas in which systems analysis HEL codes are deficient. Most notably, av...

E. B. Rockower

1985-01-01

324

Coded Orthogonal Signaling.  

National Technical Information Service (NTIS)

In this thesis, a new scheme of encoding orthogonal MFSK signals with convolutional codes is proposed. Instead of separating the code and the signals as is done conventionally, here the m outputs of the convolutional encoder of rate k/m are used to select...

S. Semerciler

1992-01-01

325

Insurance billing and coding.  

PubMed

The purpose of this article is to highlight the importance of understanding various numeric and alpha-numeric codes for accurately billing dental and medically related services to private pay or third-party insurance carriers. In the United States, common dental terminology (CDT) codes are most commonly used by dentists to submit claims, whereas current procedural terminology (CPT) and International Classification of Diseases, Ninth Revision, Clinical Modification (ICD.9.CM) codes are more commonly used by physicians to bill for their services. The CPT and ICD.9.CM coding systems complement each other in that CPT codes provide the procedure and service information and ICD.9.CM codes provide the reason or rationale for a particular procedure or service. These codes are more commonly used for "medical necessity" determinations, and general dentists and specialists who routinely perform care, including trauma-related care, biopsies, and dental treatment as a result of or in anticipation of a cancer-related treatment, are likely to use these codes. Claim submissions for care provided can be completed electronically or by means of paper forms. PMID:18501731

Napier, Rebecca H; Bruelheide, Lori S; Demann, Eric T K; Haug, Richard H

2008-07-01

326

Stationary quantum source coding  

NASA Astrophysics Data System (ADS)

In this article the quantum version of the source coding theorem is obtained for a completely ergodic source. This result extends Schumacher's quantum noiseless coding theorem for memoryless sources. The control of the memory effects requires some earlier results of Hiai and Petz on high probability subspaces. Our result is equivalently considered as a compression theorem for noiseless stationary channels.

Petz, Dénes; Mosonyi, Milán

2001-10-01

327

International Code Council  

NSDL National Science Digital Library

The International Code Council is �a membership association dedicated to building safety and fire prevention, develops the codes used to construct residential and commercial buildings, including homes and schools. Most U.S. cities, counties and states that adopt codes choose the International Codes developed by the International Code Council.� Although some sections of the site are reserved for members only (which requires a fee), there is a remarkable amount of material available to non-members. Available on the website are details about codes development, how to acquire an opinion on a code from multiple sources and how to reach a building code liaison for your locality. Under the �Certification and Testing� tab, users can find sample certification exam questions as well as outlines. The site also provides links to various periodicals, ICC meetings and also includes an event calendar to see dates for industry conferences and upcoming trade shows.

2006-12-04

328

Dress Codes for Teachers?  

ERIC Educational Resources Information Center

In this article, the author discusses an e-mail survey of principals from across the country regarding whether or not their school had a formal staff dress code. The results indicate that most did not have a formal dress code, but agreed that professional dress for teachers was not only necessary, but showed respect for the school and had a…

Million, June

2004-01-01

329

Reed-Muller Codes,  

National Technical Information Service (NTIS)

The report is the work-out of a series of talks given at the Delft Colloquium on Coding Theory in the years 1983-1984 and 1985-1986. The aim was to develop the theory of binary Reed-Muller codes from its natural basis: IF2-affine spaces. Although no new r...

J. Simonis

1987-01-01

330

Lichenase and coding sequences  

DOEpatents

The present invention provides a fungal lichenase, i.e., an endo-1,3-1,4-.beta.-D-glucanohydrolase, its coding sequence, recombinant DNA molecules comprising the lichenase coding sequences, recombinant host cells and methods for producing same. The present lichenase is from Orpinomyces PC-2.

Li, Xin-Liang (Athens, GA); Ljungdahl, Lars G. (Athens, GA); Chen, Huizhong (Lawrenceville, GA)

2000-08-15

331

Model Student Publications Code.  

ERIC Educational Resources Information Center

This outline of a model student publications code is offered as a sample on which local districts can model a Publications Code of their own. The outline begins with a Preamble which explains First Amendment rights and student rights. It continues with the following sections: I. Statement of Policy; II. Protected Speech; III. Official Student…

Journalism Education Association.

332

Buyer/Seller Codes.  

National Technical Information Service (NTIS)

The Buyer/Seller Codes in this publication are six digit code numbers assigned to buyers and sellers of natural gas for use in Federal Energy Regulatory Commission (FERC) data collection efforts. The publication is organized alphabetically by name. (ERA c...

J. Ryan M. Hirsh

1979-01-01

333

UUGM code development  

Microsoft Academic Search

The primary objective of SAIC was to develop an unstructured grid algorithm and code that dynamically adapts to the computed solution of the time dependent Euler equations of gasdynamics in two and three spatial dimensions. Important requirements that were imposed on the algorithm were: robustness, accuracy, efficiency, flexibility, and adaptability. The main research and code development effort was focused on

S. Eidelman

1993-01-01

334

Fluka Code: An Overview.  

National Technical Information Service (NTIS)

FLUKA is a multipurpose Monte Carlo code which can transport a variety of particles over a wide energy range in complex geometries. The code is a joint project of INFN and CERN: part of its development is also supported by the University of Houston and NA...

F. Ballarini G. Battistoni M. Campanella M. Carboni F. Cerutti A. Empol A. Fasso A. Ferrari E. Gadioli M. V. Garzelli

2005-01-01

335

Distributed lossless coding of hyperspectral images  

Microsoft Academic Search

In this paper we propose a novel distributed lossless compression scheme for hyperspectral images. All the images\\/bands are encoded independently, and the spectral correlation is exploited using distributed coding technologies in order to achieve low encoding complexity. At the encoder, sub-sampled images are successively encoded and transmitted. At the decoder, side information is generated with the knowledge of decoded sub-sampled

Wei Zhang; Qiwei Liu; Houqiang Li

2010-01-01

336

Energy Conservation Code Decoded  

SciTech Connect

Designing an energy-efficient, affordable, and comfortable home is a lot easier thanks to a slime, easier to read booklet, the 2006 International Energy Conservation Code (IECC), published in March 2006. States, counties, and cities have begun reviewing the new code as a potential upgrade to their existing codes. Maintained under the public consensus process of the International Code Council, the IECC is designed to do just what its title says: promote the design and construction of energy-efficient homes and commercial buildings. Homes in this case means traditional single-family homes, duplexes, condominiums, and apartment buildings having three or fewer stories. The U.S. Department of Energy, which played a key role in proposing the changes that resulted in the new code, is offering a free training course that covers the residential provisions of the 2006 IECC.

Cole, Pam C.; Taylor, Zachary T.

2006-09-01

337

Combustion chamber analysis code  

NASA Technical Reports Server (NTRS)

A three-dimensional, time dependent, Favre averaged, finite volume Navier-Stokes code has been developed to model compressible and incompressible flows (with and without chemical reactions) in liquid rocket engines. The code has a non-staggered formulation with generalized body-fitted-coordinates (BFC) capability. Higher order differencing methodologies such as MUSCL and Osher-Chakravarthy schemes are available. Turbulent flows can be modeled using any of the five turbulent models present in the code. A two-phase, two-liquid, Lagrangian spray model has been incorporated into the code. Chemical equilibrium and finite rate reaction models are available to model chemically reacting flows. The discrete ordinate method is used to model effects of thermal radiation. The code has been validated extensively against benchmark experimental data and has been applied to model flows in several propulsion system components of the SSME and the STME.

Przekwas, A. J.; Lai, Y. G.; Krishnan, A.; Avva, R. K.; Giridharan, M. G.

1993-01-01

338

Evolving genetic code  

PubMed Central

In 1985, we reported that a bacterium, Mycoplasma capricolum, used a deviant genetic code, namely UGA, a “universal” stop codon, was read as tryptophan. This finding, together with the deviant nuclear genetic codes in not a few organisms and a number of mitochondria, shows that the genetic code is not universal, and is in a state of evolution. To account for the changes in codon meanings, we proposed the codon capture theory stating that all the code changes are non-disruptive without accompanied changes of amino acid sequences of proteins. Supporting evidence for the theory is presented in this review. A possible evolutionary process from the ancient to the present-day genetic code is also discussed.

OHAMA, Takeshi; INAGAKI, Yuji; BESSHO, Yoshitaka; OSAWA, Syozo

2008-01-01

339

Applications of numerical codes to space plasma problems  

NASA Technical Reports Server (NTRS)

Solar wind, earth's bowshock, and magnetospheric convection and substorms were investigated. Topics discussed include computational physics, multifluid codes, ionospheric irregularities, and modeling laser plasmas.

Northrop, T. G.; Birmingham, T. J.; Jones, F. C.; Wu, C. S.

1975-01-01

340

Analyzing the co-evolution of comments and source code  

Microsoft Academic Search

Source code comments are a valuable instrument to preserve design decisions and to communicate the intent of the code to programmers\\u000a and maintainers. Nevertheless, commenting source code and keeping comments up-to-date is often neglected for reasons of time\\u000a or programmers obliviousness. In this paper, we investigate the question whether developers comment their code and to what\\u000a extent they add comments

Beat Fluri; Michael Würsch; Emanuel Giger; Harald C. Gall

2009-01-01

341

Local Equivalence of Surface Code States  

NASA Astrophysics Data System (ADS)

Surface code states are an important class of stabilizer states that play a prominent role in quantum information processing. In this paper we show that these states do not contain any counterexamples to the recently disproved LU-LC conjecture. In the process we show that An important consequence of our result is that surface codes do not have any encoded non-Clifford transversal gates. We also prove some interesting structural properties of the CSS surface code states. We show that these states can be characterized as a class of minor closed binary matroids. This characterization could be of independent interest in that it makes a connection with the theory of binary matroids.

Sarvepalli, Pradeep; Raussendorf, Robert

342

"Code stroke": hospitalized versus emergency department patients.  

PubMed

Stroke rapid-response ("code stroke") teams facilitate the evaluation and treatment of patients presenting to emergency departments (EDs). Little is known about the usefulness of code stroke systems for patients hospitalized primarily for other conditions. We hypothesized that the yield of code stroke evaluations would be lower in hospitalized than in ED patients, and sought to identify potential targets for quality improvement efforts. Diagnoses and management of in-hospital and ED code stroke patients were assessed retrospectively in a Joint Commission-certified primary stroke center over a 1-year period. A total of 93 in-hospital and 204 ED code strokes were identified during this period. Compared with the ED patients, the hospitalized patients were less likely to have had a stroke/transient ischemic attack (26.8% vs 51.4%; P < .0001) and less likely to have been treated with a thrombolytic agent (odds ratio, 0.27; 95% confidence interval, 0.07-0.97: P = .03). Conditions not necessitating immediate neurologic care accounted for 63.4% of in-hospital strokes, compared with 31.3% of ED code strokes (P < .0001). "Altered mental status" was the sole presenting symptom in 48% of the hospitalized patients, compared with only 10% of ED patients (P < .0001), and was the only clinical feature independently associated with a stroke mimic in the hospitalized patients (odds ratio, 63.52; 95% confidence interval, 7.37-547.69; P = .0002). There was no association between a final diagnosis of a stroke mimic and patient age, sex or race-ethnicity or nursing shift. The proportions of patients with acute ischemic stroke and patients treated with thrombolytics after activation of in-hospital code stroke were small, and were lower than those of patients with ED code stroke in the same hospital over the same time period. Developing a standardized assessment protocol for hospitalized patients with altered mental status may improve the efficacy of care. PMID:22206693

El Husseini, Nada; Goldstein, Larry B

2013-05-01

343

Distributed source coding using T-direct codes  

Microsoft Academic Search

Distributed source coding is a general framework that applies to sensor networks. Recently, considerable research on the distributed source coding of correlated sources have rekindled research scientists and engineers because of its possible application to video compression. In the sequel, distributed source coding methods like DISCUS (distributed source coding using syndromes), PRISM (power efficient, robust, high compression, syndrome-based multimedia coding)

R. S. Raja Durai

2006-01-01

344

Multi-level bandwidth efficient block modulation codes  

NASA Technical Reports Server (NTRS)

The multilevel technique is investigated for combining block coding and modulation. There are four parts. In the first part, a formulation is presented for signal sets on which modulation codes are to be constructed. Distance measures on a signal set are defined and their properties are developed. In the second part, a general formulation is presented for multilevel modulation codes in terms of component codes with appropriate Euclidean distances. The distance properties, Euclidean weight distribution and linear structure of multilevel modulation codes are investigated. In the third part, several specific methods for constructing multilevel block modulation codes with interdependency among component codes are proposed. Given a multilevel block modulation code C with no interdependency among the binary component codes, the proposed methods give a multilevel block modulation code C which has the same rate as C, a minimum squared Euclidean distance not less than that of code C, a trellis diagram with the same number of states as that of C and a smaller number of nearest neighbor codewords than that of C. In the last part, error performance of block modulation codes is analyzed for an AWGN channel based on soft-decision maximum likelihood decoding. Error probabilities of some specific codes are evaluated based on their Euclidean weight distributions and simulation results.

Lin, Shu

1989-01-01

345

Marketing Handbook for Independent Schools.  

ERIC Educational Resources Information Center

This publication is a resource to help independent schools attract more familites to their institutions and to increase the voluntary support by the larger community surrounding the school. The first chapter attempts to dispel misconceptions, define pertinent marketing terms, and relate their importance to independent schools. The rest of the book…

Boarding Schools, Boston, MA.

346

Board and Monitoring Committee Independence  

Microsoft Academic Search

This study focuses on the composition of boards of directors and their monitoring committees (audit and compensation) for large Australian companies. For firms whose boards use a committee structure, much of the monitoring responsibility of the board is expected to rest with the independent committee members. We document a positive association between the proportion of independent directors on the full

Julie Cotter; Mark Silvester

2003-01-01

347

A code in the protein coding genes  

Microsoft Academic Search

A statistical analysis with 12?288 autocorrelation functions applied in protein (coding) genes of prokaryotes and eukaryotes identifies three subsets of trinucleotides in their three frames: T0=X0?{AAA, TTT} with X0={AAC, AAT, ACC, ATC, ATT, CAG, CTC, CTG, GAA, GAC, GAG, GAT, GCC, GGC, GGT, GTA, GTC, GTT, TAC, TTC} in frame 0 (the reading frame established by the ATG start trinucleotide),

Didier G Arquès; Christian J Michel

1997-01-01

348

Growing Salt: An Independent Course Research Project Investigating Chemical Sediments  

NSDL National Science Digital Library

To prepare for this project, students read a journal article about the processes and products of chemical sedimentation and early diagenesis in saline pan environments (Lowenstein and Hardie, 1985). In class, students are given some handouts that tabluate various evaporite minerals and how water chemistry affects their formation and dissolution. A short slide show and video illustrate some different types of saline environments. Photos and samples guide a lecture on the formation of different types of evaporite minerals and how they form. For example, chevron halite crystals are generally large (cm-scale) and grow upward from the floor of a shallow (less than ~0.5 m) surface water body; cumulate halite crystals are smaller (typically mm-scale) and grow on the water-air interface and settle to the bottom, regardless of water depth. Randomly-oriented halite crystals can grow displacively from groundwater in mud or sand. The students learn that the specific sedimentology of halite can be used to trace past surface water depth and groundwater salinity. I also give examples of how past quantitative climate data, past chemical data and even past microbiologial data can be interpreted from evaporites. I emphasize how, in order to understand evaporites, one must think critically about sedimentology and geochemistry. The students are told, at the end of this lecture, that their next lab period will focus on designing and setting up a research project on growing salt. They are encouraged to start thinking about a research question they can pose about evaporite sedimentology. At this time, I also tell them what materials are available for their use (tap water, distilled water, seawater, various types of saline water I have collected during field trips, various types of store-bought table and road salt (including iodized, non-iodized, sea salt, etc.). A variety of table salts can be purchased cheaply (~$1 - $2/carton) at almost any grocery store. If you live in a cold climate, most grocery stores and hardware stores also sell several types of road salt (~$3-$4/bag). The table salts are mostly Na and Cl; some have lesser amopunts of Ca and SO4. Some road salts have Ca, Mg, Na, and Cl. In my experience, one carton and one bag of each type will provide more than enough salt for a class of 15 students. When it is time for lab to begin, I gather my students in my research lab (but could also be done in a classroom), where I show them the materials I have available to them: various types of salt, various types of water, and plastic, glass, and metal containers of various shapes (baby food glass jars, plastic take-out food containers, etc). My lab also contains a variety of other miscellaneous materials, such as sand, gravel, clay, morter and pestle, wooden sticks, metal stirring rods, string, plastic tubing, beakers, food coloring (shows fluid inclusion bands well and everyone loves playing with food coloring), etc. I remind the students that they have a microwave oven, a freezer, a lab hood, a windowsill with plenty of sunlight, and a heating vent that can be used, as well. I make available a few thermometers, pH strips (or pH meter), and a hand-held refractometer for measuring salinity. These analytical field instruments are not neccessary for this assignment to work. However, as instructor, I would encourage you to use anything available to you. I ask each student to tell me informally of their research question/hypothesis and then I try to help them find any materials they need for their experiments. Here are some examples of student research questions that have been tested with this assignment: (1) Does temperature of water affect rate of haite/gypsum growth?: (2) Will evaporite minerals grown from a complex saline fluid form a "bulls eye" pattern as their textbook claims?; (3) Will halite grow preferentially on glass substrates versus wooden and plastic substrates?; (4) Will evaporation of salt water make halite cement equally well in a gravel, a sand, a clay?; (5) What conditions best produce large halite crystals?; (6) Does pH of water influence halite and gypsum precipitation or dissolution? Students spend most of a lab period (2-3 hours) setting up their experiment. As part of this initial experimental set-up, they start to learn basic research skills such as labelling samples well, documenting starting conditions, and taking detailed notes. The students are allowed to leave their experiments on a windowsill in my lab or our classroom, on a radiator, in a lab fume hood, or in a lab refridgerator or freezer, depending upon the nature of the particular experiment. I encourage the students to check their samples on a daily basis and remind them to record their observations each time they check their experiment. I give the students an assignment sheet that details the final lab report requirements. Most students will have results in 2-3 weeks, but some experiments may last up to 4-5 weeks. For this reason, I plan for this lab assignment to be started in the middle of the semester (which works well if your syllabus, like mine, calls for weathering, physical sedimentology, siliciclastics, and carbonates to be covered in the first 6-8 weeks of class; evaporites follow well after carbonates). The final lab report is not due until the end of the semester so that all students have time to bring their expermient to completion, make interpretations, and write their lab report. At the end of the semester, depending on the number of students and time permitted, I ask the students to informally tell the class about their experiment and show the results. This has worked well for me. However, even in semesters in which we have not done this, the students still become familiar with each other's projects. On the initial experiment day, the students informally share their ideas. As students come to check on their own experiiments periodically, they usually look in on their classmates' experiments as well. Students tell me that this is one of their favorite lab exercises. It encourages critical thinking and shows the importance of experimentation in science. In addition, I feel as if the students leave my course knowing more about evaporites than the average geologist.

Benison, Kathy

349

Parental Beliefs about Emotions Are Associated with Early Adolescents' Independent and Interdependent Self-Construals  

ERIC Educational Resources Information Center

We assessed linkages between parents' beliefs and their children's self-construals with 60 7th and 8th graders. Early adolescents completed an open-ended, Self-Guide Questionnaire and an independent and interdependent reaction-time measure. The self-guide responses were coded for independent and interdependent traits. Parents reported beliefs…

Her, Pa; Dunsmore, Julie C.

2011-01-01

350

Efficient auditory coding.  

PubMed

The auditory neural code must serve a wide range of auditory tasks that require great sensitivity in time and frequency and be effective over the diverse array of sounds present in natural acoustic environments. It has been suggested that sensory systems might have evolved highly efficient coding strategies to maximize the information conveyed to the brain while minimizing the required energy and neural resources. Here we show that, for natural sounds, the complete acoustic waveform can be represented efficiently with a nonlinear model based on a population spike code. In this model, idealized spikes encode the precise temporal positions and magnitudes of underlying acoustic features. We find that when the features are optimized for coding either natural sounds or speech, they show striking similarities to time-domain cochlear filter estimates, have a frequency-bandwidth dependence similar to that of auditory nerve fibres, and yield significantly greater coding efficiency than conventional signal representations. These results indicate that the auditory code might approach an information theoretic optimum and that the acoustic structure of speech might be adapted to the coding capacity of the mammalian auditory system. PMID:16495999

Smith, Evan C; Lewicki, Michael S

2006-02-23

351

Pyramid image codes  

NASA Technical Reports Server (NTRS)

All vision systems, both human and machine, transform the spatial image into a coded representation. Particular codes may be optimized for efficiency or to extract useful image features. Researchers explored image codes based on primary visual cortex in man and other primates. Understanding these codes will advance the art in image coding, autonomous vision, and computational human factors. In cortex, imagery is coded by features that vary in size, orientation, and position. Researchers have devised a mathematical model of this transformation, called the Hexagonal oriented Orthogonal quadrature Pyramid (HOP). In a pyramid code, features are segregated by size into layers, with fewer features in the layers devoted to large features. Pyramid schemes provide scale invariance, and are useful for coarse-to-fine searching and for progressive transmission of images. The HOP Pyramid is novel in three respects: (1) it uses a hexagonal pixel lattice, (2) it uses oriented features, and (3) it accurately models most of the prominent aspects of primary visual cortex. The transform uses seven basic features (kernels), which may be regarded as three oriented edges, three oriented bars, and one non-oriented blob. Application of these kernels to non-overlapping seven-pixel neighborhoods yields six oriented, high-pass pyramid layers, and one low-pass (blob) layer.

Watson, Andrew B.

1990-01-01

352

Trellis coding with multidimensional QAM signal sets  

Microsoft Academic Search

Trellis coding using multidimensional quadrature amplitude modulation (QAM) signal sets is investigated. Finite-size 2D signal sets are presented that have minimum average energy, are 90° rotationally symmetric, and have from 16 to 1024 points. The best trellis codes using the finite 16-QAM signal set with two, four, six, and eight dimensions are found by computer search (the multidimensional (multi-D) signal

Steven S. Pietrobon; Daniel J. Costello Jr.

1993-01-01

353

Zero-Knowledge and Code Obfuscation  

Microsoft Academic Search

In this paper, we investigate the gap between auxiliary-input zero-knowledge (AIZK) and blackbox-simulation zero-knowledge (BSZK). It is an interestingopen problem whether or not there exists a proto- col which achieves AIZK, but not BSZK. We show that the existence of such a protocol is closely related to the existence of secure code obfus- cators. A code obfuscator is used to

Satoshi Hada

2000-01-01

354

Power allocation for coded cooperative communications  

Microsoft Academic Search

A power allocation in a coded cooperation is investigated. For given a total transmit power, an optimal transmit power ratio is obtained in a sense that the average received signal-to-noise ratio (SNR) from the source node and that from the relay node are equal at the sink node. Simulation for a rate compatible punctured convolutional (RCPC) code-based cooperation shows that

Naruhiko Fujiwara; Makoto Yasutake; Chen Sun; Jun Cheng; Yoichiro Watanabe

2009-01-01

355

A cascaded coding scheme for error control  

NASA Technical Reports Server (NTRS)

A cascade coding scheme for error control is investigated. The scheme employs a combination of hard and soft decisions in decoding. Error performance is analyzed. If the inner and outer codes are chosen properly, extremely high reliability can be attained even for a high channel bit-error-rate. Some example schemes are evaluated. They seem to be quite suitable for satellite down-link error control.

Shu, L.; Kasami, T.

1985-01-01

356

A cascaded coding scheme for error control  

NASA Technical Reports Server (NTRS)

A cascaded coding scheme for error control was investigated. The scheme employs a combination of hard and soft decisions in decoding. Error performance is analyzed. If the inner and outer codes are chosen properly, extremely high reliability can be attained even for a high channel bit-error-rate. Some example schemes are studied which seem to be quite suitable for satellite down-link error control.

Kasami, T.; Lin, S.

1985-01-01

357

Space-frequency coded broadband OFDM systems  

Microsoft Academic Search

Space-time coding for fading channels is a communication technique that realizes the diversity benefits of multiple transmit antennas. Previous work in this area has focused on the narrowband flat fading case where spatial diversity only is available. We investigate the use of space-time coding in OFDM-based broadband systems where both spatial and frequency diversity are available. We consider a strategy

Helmut Bolcskei; Arogyaswami J. Paulraj

2000-01-01

358

Interactive Concatenated Turbo Coding System.  

National Technical Information Service (NTIS)

This paper presents a concatenated turbo coding system in which a Reed-Solomon outer code is concatenated with a binary turbo inner code. In the proposed system, the outer code decoder and the inner turbo code decoder interact to achieve both good bit err...

Y. Liu H. Tang S. Lin M. Fossorier

1999-01-01

359

On Multiterminal Source Code Design  

Microsoft Academic Search

Multiterminal (MT) source coding refers to separate lossy encoding and joint decod- ing of multiple correlated sources. This paper presents two practical MT coding schemes under the same general framework of Slepian-Wolf coded quantization (SWCQ) for both direct and indirect quadratic Gaussian MT source coding problems with two encoders. The first asymmetric SWCQ scheme relies on quantization and Wyner-Ziv coding,

Yang Yang; Vladimir Stankovic; Zixiang Xiong; Wei Zhao

2005-01-01

360

A new multilevel coding method using error-correcting codes  

Microsoft Academic Search

A new multilevel coding method that uses several error-correcting codes is proposed. The transmission symbols are constructed by combining symbols of codewords of these codes. Usually, these codes are binary error-correcting codes and have different error-correcting capabilities. For various channels, efficient systems can be obtained by choosing these codes appropriately. Encoding and decoding procedures for this method are relatively simple

H. Imai; S. Hirakawa

1977-01-01

361

Bladder Coding Guidelines  

Cancer.gov

Coding Guidelines BLADDER C670–C679 Primary Site C670 Trigone of bladder Base of bladder Floor Below interureteric ridge (interureteric crest, or interureteric fold) C671 Dome of bladder Vertex Roof Vault C672 Lateral wall of bladder

362

Uniform Family Code.  

National Technical Information Service (NTIS)

A uniform statute is proposed governing the creation and dissolution of marriage to replace the current diversity of marriages and divorce codes, establishing 'irretrievable breakdown of the marriage relationship' as the sole basis for its dissolution. Th...

1970-01-01

363

Shell Shock Structural Code.  

National Technical Information Service (NTIS)

SHELL SHOCK is a computer code that performs a frequency analysis and determines the static and dynamic response of any structure represented by mass, damping, and stiffness matrices. These matrices may be formed directly by the user, formed internally by...

J. E. Grant V. K. Gabrielson

1975-01-01

364

The STAGS computer code  

NASA Technical Reports Server (NTRS)

Basic information about the computer code STAGS (Structural Analysis of General Shells) is presented to describe to potential users the scope of the code and the solution procedures that are incorporated. Primarily, STAGS is intended for analysis of shell structures, although it has been extended to more complex shell configurations through the inclusion of springs and beam elements. The formulation is based on a variational approach in combination with local two dimensional power series representations of the displacement components. The computer code includes options for analysis of linear or nonlinear static stress, stability, vibrations, and transient response. Material as well as geometric nonlinearities are included. A few examples of applications of the code are presented for further illustration of its scope.

Almroth, B. O.; Brogan, F. A.

1978-01-01

365

Sequence independent amplification of DNA  

DOEpatents

The present invention is a rapid sequence-independent amplification procedure (SIA). Even minute amounts of DNA from various sources can be amplified independent of any sequence requirements of the DNA or any a priori knowledge of any sequence characteristics of the DNA to be amplified. This method allows, for example the sequence independent amplification of microdissected chromosomal material and the reliable construction of high quality fluorescent in situ hybridization (FISH) probes from YACs or from other sources. These probes can be used to localize YACs on metaphase chromosomes but also--with high efficiency--in interphase nuclei.

Bohlander, Stefan K. (Chicago, IL)

1998-01-01

366

Sequence independent amplification of DNA  

DOEpatents

The present invention is a rapid sequence-independent amplification procedure (SIA). Even minute amounts of DNA from various sources can be amplified independent of any sequence requirements of the DNA or any a priori knowledge of any sequence characteristics of the DNA to be amplified. This method allows, for example, the sequence independent amplification of microdissected chromosomal material and the reliable construction of high quality fluorescent in situ hybridization (FISH) probes from YACs or from other sources. These probes can be used to localize YACs on metaphase chromosomes but also--with high efficiency--in interphase nuclei. 25 figs.

Bohlander, S.K.

1998-03-24

367

High-Speed Soft-Decision Decoding of Two Reed-Muller Codes  

NASA Technical Reports Server (NTRS)

In this research, we have proposed the (64, 40, 8) subcode of the third-order Reed-Muller (RM) code to NASA for high-speed satellite communications. This RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. This report will summarize the key progress we have made toward achieving our eventual goal of implementing, a decoder system based upon this code. In the first phase of study, we investigated the complexities of various sectionalized trellis diagrams for the proposed (64, 40, 8) RM subcode. We found a specific 8-trellis diagram for this code which requires the least decoding complexity with a high possibility of achieving a decoding speed of 600 M bits per second (Mbps). The combination of a large number of states and a high data rate will be made possible due to the utilization of a high degree of parallelism throughout the architecture. This trellis diagram will be presented and briefly described. In the second phase of study, which was carried out through the past year, we investigated circuit architectures to determine the feasibility of VLSI implementation of a high-speed Viterbi decoder based on this 8-section trellis diagram. We began to examine specific design and implementation approaches to implement a fully custom integrated circuit (IC) which will be a key building block for a decoder system implementation. The key results will be presented in this report. This report will be divided into three primary sections. First, we will briefly describe the system block diagram in which the proposed decoder is assumed to be operating, and present some of the key architectural approaches being used to implement the system at high speed. Second, we will describe details of the 8-trellis diagram we found to best meet the trade-offs between chip and overall system complexity. The chosen approach implements the trellis for the (64, 40, 8) RM subcode with 32 independent sub-trellises. And third, we will describe results of our feasibility study on the implementation of such an IC chip in CMOS technology to implement one of these sub-trellises.

Lin, Shu; Uehara, Gregory T.

1996-01-01

368

High-Speed Soft-Decision Decoding of Two Reed-Muller Codes  

NASA Technical Reports Server (NTRS)

In his research, we have proposed the (64, 40, 8) subcode of the third-order Reed-Muller (RM) code to NASA for high-speed satellite communications. This RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. This report will summarize the key progress we have made toward achieving our eventual goal of implementing a decoder system based upon this code. In the first phase of study, we investigated the complexities of various sectionalized trellis diagrams for the proposed (64, 40, 8) RNI subcode. We found a specific 8-trellis diagram for this code which requires the least decoding complexity with a high possibility of achieving a decoding speed of 600 M bits per second (Mbps). The combination of a large number of states and a hi ch data rate will be made possible due to the utilization of a high degree of parallelism throughout the architecture. This trellis diagram will be presented and briefly described. In the second phase of study which was carried out through the past year, we investigated circuit architectures to determine the feasibility of VLSI implementation of a high-speed Viterbi decoder based on this 8-section trellis diagram. We began to examine specific design and implementation approaches to implement a fully custom integrated circuit (IC) which will be a key building block for a decoder system implementation. The key results will be presented in this report. This report will be divided into three primary sections. First, we will briefly describe the system block diagram in which the proposed decoder is assumed to be operating and present some of the key architectural approaches being used to implement the system at high speed. Second, we will describe details of the 8-trellis diagram we found to best meet the trade-offs between chip and overall system complexity. The chosen approach implements the trellis for the (64, 40, 8) RM subcode with 32 independent sub-trellises. And third, we will describe results of our feasibility study on the implementation of such an IC chip in CMOS technology to implement one of these sub-trellises.

Lin, Shu; Uehara, Gregory T.

1996-01-01

369

Reversibility and efficiency in coding protein information.  

PubMed

Why the genetic code has a fixed length? Protein information is transferred by coding each amino acid using codons whose length equals 3 for all amino acids. Hence the most probable and the least probable amino acid get a codeword with an equal length. Moreover, the distributions of amino acids found in nature are not uniform and therefore the efficiency of such codes is sub-optimal. The origins of these apparently non-efficient codes are yet unclear. In this paper we propose an a priori argument for the energy efficiency of such codes resulting from their reversibility, in contrast to their time inefficiency. Such codes are reversible in the sense that a primitive processor, reading three letters in each step, can always reverse its operation, undoing its process. We examine the codes for the distributions of amino acids that exist in nature and show that they could not be both time efficient and reversible. We investigate a family of Zipf-type distributions and present their efficient (non-fixed length) prefix code, their graphs, and the condition for their reversibility. We prove that for a large family of such distributions, if the code is time efficient, it could not be reversible. In other words, if pre-biotic processes demand reversibility, the protein code could not be time efficient. The benefits of reversibility are clear: reversible processes are adiabatic, namely, they dissipate a very small amount of energy. Such processes must be done slowly enough; therefore time efficiency is non-important. It is reasonable to assume that early biochemical complexes were more prone towards energy efficiency, where forward and backward processes were almost symmetrical. PMID:20868696

Tamir, Boaz; Priel, Avner

2010-12-21

370

MELCOR computer code manuals  

Microsoft Academic Search

MELCOR is a fully integrated, engineering-level computer code that models the progression of severe accidents in light water reactor nuclear power plants. MELCOR is being developed at Sandia National Laboratories for the U.S. Nuclear Regulatory Commission as a second-generation plant risk assessment tool and the successor to the Source Term Code Package. A broad spectrum of severe accident phenomena in

R. M. Summers; R. K. Jr. Cole; R. C. Smith; D. S. Stuart; S. L. Thompson; S. A. Hodge; C. R. Hyman; R. L. Sanders

1995-01-01

371

Seals Flow Code Development  

NASA Technical Reports Server (NTRS)

In recognition of a deficiency in the current modeling capability for seals, an effort was established by NASA to develop verified computational fluid dynamic concepts, codes, and analyses for seals. The objectives were to develop advanced concepts for the design and analysis of seals, to effectively disseminate the information to potential users by way of annual workshops, and to provide experimental verification for the models and codes under a wide range of operating conditions.

1991-01-01

372

ORECA CODE ASSESSMENT.  

SciTech Connect

Results of an assessment of the ORECA code are being presented. In particular it was found that in the case of loss of forced flow circulation the predicted peak core temperatures are very sensitive to the mean gas temperatures used in the evaluation of the pressure drop terms. Some potential shortcomings of the conduction algorithm for some specific applications are discussed. The results of these efforts have been taken into consideration in the current version of the ORECA code.

KROEGER,P.G.

1980-07-01

373

MPEG digital audio coding  

Microsoft Academic Search

The Moving Pictures Expert Group (MPEG) within the International Organization of Standardization (ISO) has developed a series of audio-visual standards known as MFEG-1 and MPEG-2. These audio-coding standards are the first international standards in the field of high-quality digital audio compression. MPEG-1 covers coding of stereophonic audio signals at high sampling rates aiming at transparent quality, whereas MPEG-2 also offers

P. Noll

1997-01-01

374

Lossy Source Coding  

Microsoft Academic Search

Lossy coding of speech, high-quality audio, stillimages, and video is commonplace today. However, in 1948, fewlossy compression systems were in service. Shannon introducedand developed the theory of source coding with a fidelity criterion,also called rate-distortion theory. For the first 25 years of itsexistence, rate-distortion theory had relatively little impact onthe methods and systems actually used to compress real sources.Today, however,

T. Berger; J. D. Gibson

1998-01-01

375

The MELCOR code: History, status, and plans  

SciTech Connect

In 1982, the U.S. Nuclear Regulatory Commission sponsored development of the MELCOR code at Sandia National Laboratories in response to the need for a calculational tool capable of performing integrated analyses of severe accidents in nuclear reactors. The intention was that all relevant phenomena would be modeled parametrically, with the level of detail for each depending both on its importance in an accident and on the consensus in the safety community concerning physical understanding of the phenomenon. MELCOR was to be `integrated` in the sense that various feedback effects would be modeled, including, but not limited to, the effects of containment conditions on in-vessel accident progression and the relocation of heat sources with the transport of radionuclides. The existing calculational tool [Source Term Code Package (STCP)] required manual transfer of data from one code to another. MELCOR eliminated this procedure and the potential error introduced. The consequences analysis was to be performed by a separate computer tool. MELCOR was peer reviewed in 1991. Most subsequent model development and improvement activities have been based on comments received in that review. All new models have been independently peer reviewed prior to incorporation into MELCOR. One of the peer review suggestions was the need for additional code assessment. This suggestion resulted in the formation of the MELCOR Cooperative Assessment Program (MCAP) as an ongoing activity to assess the code against experiments and in performing plant analyses.

Ridgely, J.N. [Nuclear Regulatory Commission, Washington, DC (United States); Cole, R.K. Jr.; Gauntt, R.O. [Sandia National Laboratories, Albuquerque, NM (United States)

1996-12-31

376

Analysis of static coded aperture imaging spectrometer  

NASA Astrophysics Data System (ADS)

Scanning and interference imaging spectrometer are widely used in earth observing, microscope imaging, etc. Motion mechanisms are utilized in all these simple imaging spectrometers, which make the system big, expensive and unstable. A novel static non-imaging spectrometer is introduced specifically. 2D (two-dimension) static multi-channel spectral measurement is realized in this spectrometer, utilizing 2D hadamard matrix code mask and 2D detector. The hadamard matrix is different from traditional S circular code. The orthogonal property of hadamard matrix is utilized, and with special transform negative codes in hadamard matrix are also realized. Basing on this non-imaging spectrometer static imaging spectrometer is developed. First 2D imaging spectrometer can be divided into many 1D ones which work independently. The 1D imaging spectrometer is obtained with position information added into the hadamard coding system in dispersive direction. To get 2D imaging spectrometer, extend the coded aperture: put some masks together in non-dispersive direction. According to this model, the spectrum of an image instead of a slit can be estimated at one time. The optical system is designed to simulate the imaging spectrometer. Compared to the simple scanning imaging spectrometer the simulated result shows the model's resolution can be compared to simple scanning spectrometer, but the scanning time of simple scanning imaging spectrometer is about 3 times of our simulation. At last some implementation issues are mentioned.

Gong, Xingzhi; Cheng, Liang; Ye, Zi; Yu, Feihong

2008-03-01

377

Alienation Among Sorority and Independent Freshmen at a Women's College.  

ERIC Educational Resources Information Center

Alienation is experienced by adolescents in varying degrees; however, little research has investigated alienation in relationship to Greek sorority/fraternity membership versus independent status among college students. To measure alienation among freshmen sorority members and freshmen independents in a small women's college, 60 women completed…

Prisco, Dorothy D.

378

Coded aperture compressive temporal imaging.  

PubMed

We use mechanical translation of a coded aperture for code division multiple access compression of video. We discuss the compressed video's temporal resolution and present experimental results for reconstructions of > 10 frames of temporal data per coded snapshot. PMID:23669910

Llull, Patrick; Liao, Xuejun; Yuan, Xin; Yang, Jianbo; Kittle, David; Carin, Lawrence; Sapiro, Guillermo; Brady, David J

2013-05-01

379

Technology for Independent Living: Sourcebook.  

ERIC Educational Resources Information Center

This sourcebook provides information for the practical implementation of independent living technology in the everyday rehabilitation process. "Information Services and Resources" lists databases, clearinghouses, networks, research and development programs, toll-free telephone numbers, consumer protection caveats, selected publications, and…

Enders, Alexandra, Ed.

380

Independent Schools: Landscape and Learnings.  

ERIC Educational Resources Information Center

Examines American independent schools (parochial, southern segregated, and private institutions) in terms of their funding, expenditures, changing enrollment patterns, teacher-student ratios, and societal functions. Journal available from Daedalus Subscription Department, 1172 Commonwealth Ave., Boston, MA 02132. (AM)

Oates, William A.

1981-01-01

381

Independent component analysis: recent advances.  

PubMed

Independent component analysis is a probabilistic method for learning a linear transform of a random vector. The goal is to find components that are maximally independent and non-Gaussian (non-normal). Its fundamental difference to classical multi-variate statistical methods is in the assumption of non-Gaussianity, which enables the identification of original, underlying components, in contrast to classical methods. The basic theory of independent component analysis was mainly developed in the 1990s and summarized, for example, in our monograph in 2001. Here, we provide an overview of some recent developments in the theory since the year 2000. The main topics are: analysis of causal relations, testing independent components, analysing multiple datasets (three-way data), modelling dependencies between the components and improved methods for estimating the basic model. PMID:23277597

Hyvärinen, Aapo

2013-02-13

382

Scale-Independent Biomechanical Optimization.  

National Technical Information Service (NTIS)

In this paper, the authors present a scale-independent method of optimization with a stochastic global optimization approach introduced by Kennedy and Eberhart: the Particle Swarm Optimizer (PSO). They apply this method to the biomechanical system identif...

J. F. Schutte B. Koh J. A. Reinbolt R. T. Haftka A. George

2003-01-01

383

Compound Independent and Dependent Events  

NSDL National Science Digital Library

Compare the theoretical and experimental probability of a compound independent event by drawing colored marbles from a bag. Record the results of successive draws with or without replacement of marbles to calculate the experimental probability.

2007-12-12

384

Optimal correction of concatenated fault-tolerant quantum codes  

NASA Astrophysics Data System (ADS)

We present a method of concatenated quantum error correction in which improved classical processing is used with existing quantum codes and fault-tolerant circuits to more reliably correct errors. Rather than correcting each level of a concatenated code independently, our method uses information about the likelihood of errors having occurred at lower levels to maximize the probability of correctly interpreting error syndromes. Results of simulations of our method applied to the [[4,1,2

Evans, Z. W. E.; Stephens, A. M.

2012-12-01

385

COMIT: identification of noncoding motifs under selection in coding sequences  

PubMed Central

Coding nucleotide sequences contain myriad functions independent of their encoded protein sequences. We present the COMIT algorithm to detect functional noncoding motifs in coding regions using sequence conservation, explicitly separating nucleotide from amino acid effects. COMIT concurs with diverse experimental datasets, including splicing enhancers, silencers, replication motifs, and microRNA targets, and predicts many novel functional motifs. Intriguingly, COMIT scores are well-correlated to scores uncalibrated for amino acids, suggesting that nucleotide motifs often override peptide-level constraints.

2009-01-01

386

Combinatorial independence in measurable dynamics  

Microsoft Academic Search

We develop a fine-scale local analysis of measure entropy and measure sequence entropy based on combinatorial independence. The concepts of measure IE-tuples and measure IN-tuples are introduced and studied in analogy with their counterparts in topological dynamics. Local characterizations of the Pinsker von Neumann algebra and its sequence entropy analogue are given in terms of combinatorial independence, ?1 geometry, and

David Kerr; Hanfeng Li

2009-01-01

387

Coding and non-coding polymorphisms in alcohol dehydrogenase alters protein expression and alcohol-associated erythema.  

PubMed

Ethanol (EtOH), isopropyl alcohol (IPA), and propylene glycol (PG) increase topical drug delivery, but are sometimes associated with erythema. A potential genetic basis for alcohol-associated erythema was investigated as the function of polymorphisms in coding and non-coding regions of class IB alcohol dehydrogenase (ADHIB) and evaluated for altered gene expression in vitro and metabolic activity in vivo via altered skin blood flow (Doppler velocimeter) and erythema (reflectance colorimeter a*) following topical challenge to 5 M EtOH, IPA, PG, and butanol (ButOH). Promoter polymorphisms G-887A and C-739T and exon G143A form eight ADHIB haplotypes with different frequencies in Caucasians vs Asians and exhibit variable gene expression and metabolic activity. Polymorphisms C-739T and G-887A independently alter gene expression, which is further increased by IPA and PG, but not EtOH or ButOH. EtOH and ButOH increase erythema as a function of skin blood flow. IPA increases skin blood flow without erythema and PG increased erythema with decreased skin blood flow, all as a function of ADHIB haplotype. PG-induced erythema was uniquely associated with tumor necrosis factor-alpha expression. Thus, erythema following alcohol exposure is alcohol type specific, has a pharmacogenetic basis related to ADHIB haplotype and can be functionally evaluated via Doppler velocimetry and reflectance colorimetry in vivo. PMID:18049455

Pershing, Lynn K; Chen, Yuexian; Tkachuk, Ariana N; Rausch, Holly L; Petelenz-Rubin, Kasia; Corlett, Judy L; Hobbs, Maurine R

2008-03-01

388

Neural coding for the retrieval of multiple memory patterns  

Microsoft Academic Search

We investigate the retrieval dynamics in a feature-based semantic memory model, in which the features are coded by neurons of the Hindmarsh–Rose type in the chaotic regime. We consider the retrieval process as consisting of the synchronized firing activity of the neurons coding for the same memory pattern. The retrieval dynamics is investigated for multiple patterns, with particular attention to

A. Morelli; R. Lauro Grotto; F. T. Arecchi

2006-01-01

389

The Sign Rule and Beyond: Boundary Effects, Flexibility, and Noise Correlations in Neural Population Codes  

PubMed Central

Over repeat presentations of the same stimulus, sensory neurons show variable responses. This “noise” is typically correlated between pairs of cells, and a question with rich history in neuroscience is how these noise correlations impact the population's ability to encode the stimulus. Here, we consider a very general setting for population coding, investigating how information varies as a function of noise correlations, with all other aspects of the problem – neural tuning curves, etc. – held fixed. This work yields unifying insights into the role of noise correlations. These are summarized in the form of theorems, and illustrated with numerical examples involving neurons with diverse tuning curves. Our main contributions are as follows. (1) We generalize previous results to prove a sign rule (SR) — if noise correlations between pairs of neurons have opposite signs vs. their signal correlations, then coding performance will improve compared to the independent case. This holds for three different metrics of coding performance, and for arbitrary tuning curves and levels of heterogeneity. This generality is true for our other results as well. (2) As also pointed out in the literature, the SR does not provide a necessary condition for good coding. We show that a diverse set of correlation structures can improve coding. Many of these violate the SR, as do experimentally observed correlations. There is structure to this diversity: we prove that the optimal correlation structures must lie on boundaries of the possible set of noise correlations. (3) We provide a novel set of necessary and sufficient conditions, under which the coding performance (in the presence of noise) will be as good as it would be if there were no noise present at all.

Hu, Yu; Zylberberg, Joel; Shea-Brown, Eric

2014-01-01

390

Refractoriness Enhances Temporal Coding by Auditory Nerve Fibers  

PubMed Central

A universal property of spiking neurons is refractoriness, a transient decrease in discharge probability immediately following an action potential (spike). The refractory period lasts only one to a few milliseconds, but has the potential to affect temporal coding of acoustic stimuli by auditory neurons, which are capable of submillisecond spike-time precision. Here this possibility was investigated systematically by recording spike times from chicken auditory nerve fibers in vivo while stimulating with repeated pure tones at characteristic frequency. Refractory periods were tightly distributed, with a mean of 1.58 ms. A statistical model was developed to recapitulate each fiber's responses and then used to predict the effect of removing the refractory period on a cell-by-cell basis for two largely independent facets of temporal coding: faithful entrainment of interspike intervals to the stimulus frequency and precise synchronization of spike times to the stimulus phase. The ratio of the refractory period to the stimulus period predicted the impact of refractoriness on entrainment and synchronization. For ratios less than ?0.9, refractoriness enhanced entrainment and this enhancement was often accompanied by an increase in spike-time precision. At higher ratios, little or no change in entrainment or synchronization was observed. Given the tight distribution of refractory periods, the ability of refractoriness to improve temporal coding is restricted to neurons responding to low-frequency stimuli. Enhanced encoding of low frequencies likely affects sound localization and pitch perception in the auditory system, as well as perception in nonauditory sensory modalities, because all spiking neurons exhibit refractoriness.

Avissar, Michael; Wittig, John H.; Saunders, James C.

2013-01-01

391

Constrained Coding for the Deep-Space Optical Channel  

NASA Astrophysics Data System (ADS)

We investigate methods of coding for a channel subject to a large dead-time constraint, i.e., a constraint on the minimum spacing between transmitted pulses, with the deep-space optical channel as the motivating example. Several constrained codes designed to satisfy the dead-time constraint are considered and compared on the basis of throughput, complexity, and decoded error rate. The performance of an iteratively decoded serial concatenation of a constrained code with an outer code is evaluated and shown to provide significant gains over a Reed-Solomon code concatenated with pulse-position modulation.

Moision, B.; Hamkins, J.

2002-01-01

392

Using Independent Component Analysis to Separate Signals in Climate Data.  

National Technical Information Service (NTIS)

Global temperature series have contributions from dierent sources, such as volcanic eruptions and El Nino Southern Oscillation variations. We investigate independent component analysis as a technique to separate unrelated sources present in such series. W...

C. Kamath I. K. Fodor

2003-01-01

393

Field-Dependence/Field Independence and Instructional Development.  

National Technical Information Service (NTIS)

A three-faceted investigation was conducted to critically analyze Witkin's conceptualization of cognitive style gleaned from his field dependence/field independence continuum, to identify cognitive style components within the instructional development lit...

D. E. Sheriff J. A. Williams

1980-01-01

394

Prioritized LT Codes  

NASA Technical Reports Server (NTRS)

The original Luby Transform (LT) coding scheme is extended to account for data transmissions where some information symbols in a message block are more important than others. Prioritized LT codes provide unequal error protection (UEP) of data on an erasure channel by modifying the original LT encoder. The prioritized algorithm improves high-priority data protection without penalizing low-priority data recovery. Moreover, low-latency decoding is also obtained for high-priority data due to fast encoding. Prioritized LT codes only require a slight change in the original encoding algorithm, and no changes at all at the decoder. Hence, with a small complexity increase in the LT encoder, an improved UEP and low-decoding latency performance for high-priority data can be achieved. LT encoding partitions a data stream into fixed-sized message blocks each with a constant number of information symbols. To generate a code symbol from the information symbols in a message, the Robust-Soliton probability distribution is first applied in order to determine the number of information symbols to be used to compute the code symbol. Then, the specific information symbols are chosen uniform randomly from the message block. Finally, the selected information symbols are XORed to form the code symbol. The Prioritized LT code construction includes an additional restriction that code symbols formed by a relatively small number of XORed information symbols select some of these information symbols from the pool of high-priority data. Once high-priority data are fully covered, encoding continues with the conventional LT approach where code symbols are generated by selecting information symbols from the entire message block including all different priorities. Therefore, if code symbols derived from high-priority data experience an unusual high number of erasures, Prioritized LT codes can still reliably recover both high- and low-priority data. This hybrid approach decides not only "how to encode" but also "what to encode" to achieve UEP. Another advantage of the priority encoding process is that the majority of high-priority data can be decoded sooner since only a small number of code symbols are required to reconstruct high-priority data. This approach increases the likelihood that high-priority data is decoded first over low-priority data. The Prioritized LT code scheme achieves an improvement in high-priority data decoding performance as well as overall information recovery without penalizing the decoding of low-priority data, assuming high-priority data is no more than half of a message block. The cost is in the additional complexity required in the encoder. If extra computation resource is available at the transmitter, image, voice, and video transmission quality in terrestrial and space communications can benefit from accurate use of redundancy in protecting data with varying priorities.

Woo, Simon S.; Cheng, Michael K.

2011-01-01

395

Construction of LDPC Codes for Coded Cooperative Relay  

Microsoft Academic Search

In this paper, we present two construction schemes for LDPC codes in coded cooperative communication. The scheme which uses rate compatible LDPC codes based on punc- turing parity bits is presented first. Then the paper proposes the scheme which uses QC-LDPC codes based on the multiplicative inverses in finite fields. Detailed implementations of two schemes are presented. Simulation results show

Zhuzhe Shen; Zesong Fei; Keke Liu; Jingming Kuang

2011-01-01

396

Source code modification technology based on parameterized code patterns  

Microsoft Academic Search

Source code modification is one of the most frequent operations which developers perform in software life cycle. Such operation can be performed in order to add new functionality, fix bugs or bad code style, optimize performance, increase readability, etc. During the modification of existing source code developer needs to find parts of code, which meet to some conditions, and change

Vladimir Itsykson; D. Timofeyev

2010-01-01

397

Coarse coding and discourse comprehension in adults with right hemisphere brain damage  

PubMed Central

Background Various investigators suggest that some discourse-level comprehension difficulties in adults with right hemisphere brain damage (RHD) have a lexical-semantic basis. As words are processed, the intact right hemisphere arouses and sustains activation of a wide-ranging network of secondary or peripheral meanings and features—a phenomenon dubbed “coarse coding”. Coarse coding impairment has been postulated to underpin some prototypical RHD comprehension deficits, such as difficulties with nonliteral language interpretation, discourse integration, some kinds of inference generation, and recovery when a reinterpretation is needed. To date, however, no studies have addressed the hypothesised link between coarse coding deficit and discourse comprehension in RHD. Aims The current investigation examined whether coarse coding was related to performance on two measures of narrative comprehension in adults with RHD. Methods & Procedures Participants were 32 adults with unilateral RHD from cerebrovascular accident, and 38 adults without brain damage. Coarse coding was operationalised as poor activation of peripheral/weakly related semantic features of words. For the coarse coding assessment, participants listened to spoken sentences that ended in a concrete noun. Each sentence was followed by a spoken target phoneme string. Targets were subordinate semantic features of the sentence-final nouns that were incompatible with their dominant mental representations (e.g., “rotten” for apple). Targets were presented at two post-noun intervals. A lexical decision task was used to gauge both early activation and maintenance of activation of these weakly related semantic features. One of the narrative tasks assessed comprehension of implied main ideas and details, while the other indexed high-level inferencing and integration. Both comprehension tasks were presented auditorily. For all tasks, accuracy of performance was the dependent measure. Correlations were computed within the RHD group between both the early and late coarse coding measures and the two discourse measures. Additionally, ANCOVA and independent t-tests were used to compare both early and sustained coarse coding in subgroups of good and poor RHD comprehenders. Outcomes & Results The group with RHD was less accurate than the control group on all measures. The finding of coarse coding impairment (difficulty activating/sustaining activation of a word’s peripheral features) may appear to contradict prior evidence of RHD suppression deficit (prolonged activation for context-inappropriate meanings of words). However, the sentence contexts in this study were unbiased and thus did not provide an appropriate test of suppression function. Correlations between coarse coding and the discourse measures were small and nonsignificant. There were no differences in coarse coding between RHD comprehension subgroups on the high-level inferencing task. There was also no distinction in early coarse coding for subgroups based on comprehension of implied main ideas and details. But for these same subgroups, there was a difference in sustained coarse coding. Poorer RHD comprehenders of implied information from discourse were also poorer at maintaining activation for semantically distant features of concrete nouns. Conclusions This study provides evidence of a variant of the postulated link between coarse coding and discourse comprehension in RHD. Specifically, adults with RHD who were particularly poor at sustaining activation for peripheral semantic features of nouns were also relatively poor comprehenders of implied information from narratives.

Tompkins, Connie A.; Scharp, Victoria L.; Meigh, Kimberly M.; Fassbinder, Wiltrud

2009-01-01

398

Code for America  

NSDL National Science Digital Library

How might we bring local governments together to make better cities? Why not try Code for America? This compelling organization works to "help residents and governments harness technology to solve community problems." Its work is supported by a range of organizations, including Google, the Kauffman Foundation, and ESRI. The site contains a number of topical sections, including Governments, Citizens, and Apps. The Governments area contains links to the ten cities that are utilizing the services of Code For America to create ambitious projects designed to connect citizens to their government. Projects have included work in Oakland and Honolulu where citizen codes rewrote these cities' websites in one day each. Both Free Apps and Paid Apps can be found here and highlight a variety of compelling new projects, such as Adopt-A-Hydrant and the Jail Population Management Dashboard.

399

Coding Theory and Performance Of Redundant Residue Number System Codes  

Microsoft Academic Search

In this contribution nonlinear coding theory is invoked in order to study redundant residue number system (RRNS) based channel codes. We analyse some unsolved problems of RRNS codes, exploring their weight-distribution, distance-distribution and coding performance. The conventional algorithms used for error-detection and error-correction in RRNS codes are im- proved and unied in the context of a 'minimum-distance decoding' algorithm, which

Lie-Liang Yang; Lajos Hanzo

400

Nonuniform unitary space-time codes for layered source coding  

Microsoft Academic Search

We discuss new space-time codes tailored to point-to-multipoint, or broadcast, communications using layered source coding. Our codes can be encoded (and decoded) differentially, and they are based entirely on phase-shift keying. We discuss design criteria for the codes, and the design of optimal and suboptimal receiver structures. We also discuss the relation between our codes and a differentially encoded Alamouti

Erik G. Larsson; Wing-hin Wong

2004-01-01

401

Plasmid-mediated NAD independence in Haemophilus parainfluenzae.  

PubMed

The location of the genes coding for NAD independence in four unusual clinical isolates of Haemophilus parainfluenzae was determined by transferring these genes to plasmid-free Haemophilus influenzae Rd by transformation and analysing transformants for the presence of plasmids by agarose gel electrophoresis. All NAD-independent transformants were found to carry a single plasmid species. The plasmids, originally harboured by the four H. parainfluenzae isolates recovered from unrelated sources, were of the same size (5.25 kb). Spontaneous reversion to NAD dependence occurred with a low frequency (0.1 to 0.2% of the progeny of a single clone) in both H. parainfluenzae and H. influenzae Rd. The revertants had lost this small plasmid. Mitomycin C exhibited a plasmid 'curing' effect with a frequency of 'curing' of between 1 and 6% of the surviving clones. It was concluded that the genes conferring NAD independence were located on the small 5.25 kb plasmid. PMID:1770356

Windsor, H M; Gromkova, R C; Koornhof, H J

1991-10-01

402

Deterministic and unambiguous dense coding  

SciTech Connect

Optimal dense coding using a partially-entangled pure state of Schmidt rank D and a noiseless quantum channel of dimension D is studied both in the deterministic case where at most L{sub d} messages can be transmitted with perfect fidelity, and in the unambiguous case where when the protocol succeeds (probability {tau}{sub x}) Bob knows for sure that Alice sent message x, and when it fails (probability 1-{tau}{sub x}) he knows it has failed. Alice is allowed any single-shot (one use) encoding procedure, and Bob any single-shot measurement. For D{<=}D a bound is obtained for L{sub d} in terms of the largest Schmidt coefficient of the entangled state, and is compared with published results by Mozes et al. [Phys. Rev. A71, 012311 (2005)]. For D>D it is shown that L{sub d} is strictly less than D{sup 2} unless D is an integer multiple of D, in which case uniform (maximal) entanglement is not needed to achieve the optimal protocol. The unambiguous case is studied for D{<=}D, assuming {tau}{sub x}>0 for a set of DD messages, and a bound is obtained for the average <1/{tau}>. A bound on the average <{tau}> requires an additional assumption of encoding by isometries (unitaries when D=D) that are orthogonal for different messages. Both bounds are saturated when {tau}{sub x} is a constant independent of x, by a protocol based on one-shot entanglement concentration. For D>D it is shown that (at least) D{sup 2} messages can be sent unambiguously. Whether unitary (isometric) encoding suffices for optimal protocols remains a major unanswered question, both for our work and for previous studies of dense coding using partially-entangled states, including noisy (mixed) states.

Wu Shengjun [Physics Department, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Hefei National Laboratory for Physical Science at the Microscale, University of Science and Technology of China (China); Cohen, Scott M. [Physics Department, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Physics Department, Duquesne University, Pittsburgh, Pennsylvania 15282 (United States); Sun Yuqing; Griffiths, Robert B. [Physics Department, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213 (United States)

2006-04-15

403

Securing mobile code.  

SciTech Connect

If software is designed so that the software can issue functions that will move that software from one computing platform to another, then the software is said to be 'mobile'. There are two general areas of security problems associated with mobile code. The 'secure host' problem involves protecting the host from malicious mobile code. The 'secure mobile code' problem, on the other hand, involves protecting the code from malicious hosts. This report focuses on the latter problem. We have found three distinct camps of opinions regarding how to secure mobile code. There are those who believe special distributed hardware is necessary, those who believe special distributed software is necessary, and those who believe neither is necessary. We examine all three camps, with a focus on the third. In the distributed software camp we examine some commonly proposed techniques including Java, D'Agents and Flask. For the specialized hardware camp, we propose a cryptographic technique for 'tamper-proofing' code over a large portion of the software/hardware life cycle by careful modification of current architectures. This method culminates by decrypting/authenticating each instruction within a physically protected CPU, thereby protecting against subversion by malicious code. Our main focus is on the camp that believes that neither specialized software nor hardware is necessary. We concentrate on methods of code obfuscation to render an entire program or a data segment on which a program depends incomprehensible. The hope is to prevent or at least slow down reverse engineering efforts and to prevent goal-oriented attacks on the software and execution. The field of obfuscation is still in a state of development with the central problem being the lack of a basis for evaluating the protection schemes. We give a brief introduction to some of the main ideas in the field, followed by an in depth analysis of a technique called 'white-boxing'. We put forth some new attacks and improvements on this method as well as demonstrating its implementation for various algorithms. We also examine cryptographic techniques to achieve obfuscation including encrypted functions and offer a new application to digital signature algorithms. To better understand the lack of security proofs for obfuscation techniques, we examine in detail general theoretical models of obfuscation. We explain the need for formal models in order to obtain provable security and the progress made in this direction thus far. Finally we tackle the problem of verifying remote execution. We introduce some methods of verifying remote exponentiation computations and some insight into generic computation checking.

Link, Hamilton E.; Schroeppel, Richard Crabtree; Neumann, William Douglas; Campbell, Philip LaRoche; Beaver, Cheryl Lynn; Pierson, Lyndon George; Anderson, William Erik

2004-10-01

404

Aeroacoustic Prediction Codes  

NASA Technical Reports Server (NTRS)

This report describes work performed on Contract NAS3-27720AoI 13 as part of the NASA Advanced Subsonic Transport (AST) Noise Reduction Technology effort. Computer codes were developed to provide quantitative prediction, design, and analysis capability for several aircraft engine noise sources. The objective was to provide improved, physics-based tools for exploration of noise-reduction concepts and understanding of experimental results. Methods and codes focused on fan broadband and 'buzz saw' noise and on low-emissions combustor noise and compliment work done by other contractors under the NASA AST program to develop methods and codes for fan harmonic tone noise and jet noise. The methods and codes developed and reported herein employ a wide range of approaches, from the strictly empirical to the completely computational, with some being semiempirical analytical, and/or analytical/computational. Emphasis was on capturing the essential physics while still considering method or code utility as a practical design and analysis tool for everyday engineering use. Codes and prediction models were developed for: (1) an improved empirical correlation model for fan rotor exit flow mean and turbulence properties, for use in predicting broadband noise generated by rotor exit flow turbulence interaction with downstream stator vanes: (2) fan broadband noise models for rotor and stator/turbulence interaction sources including 3D effects, noncompact-source effects. directivity modeling, and extensions to the rotor supersonic tip-speed regime; (3) fan multiple-pure-tone in-duct sound pressure prediction methodology based on computational fluid dynamics (CFD) analysis; and (4) low-emissions combustor prediction methodology and computer code based on CFD and actuator disk theory. In addition. the relative importance of dipole and quadrupole source mechanisms was studied using direct CFD source computation for a simple cascadeigust interaction problem, and an empirical combustor-noise correlation model was developed from engine acoustic test results. This work provided several insights on potential approaches to reducing aircraft engine noise. Code development is described in this report, and those insights are discussed.

Gliebe, P; Mani, R.; Shin, H.; Mitchell, B.; Ashford, G.; Salamah, S.; Connell, S.; Huff, Dennis (Technical Monitor)

2000-01-01

405

Highly overcomplete sparse coding  

NASA Astrophysics Data System (ADS)

This paper explores sparse coding of natural images in the highly overcomplete regime. We show that as the overcompleteness ratio approaches l0x, new types of dictionary elements emerge beyond the classical Gabor function shape obtained from complete or only modestly overcomplete sparse coding. These more diverse dic­ tionaries allow images to be approximated with lower L1 norm (for a fixed SNR), and the coefficients exhibit steeper decay. We also evaluate the learned dictionaries in a denoising task, showing that higher degrees of overcompleteness yield modest gains in peformance.

Olshausen, Bruno A.

2013-03-01

406

The Code Project  

NSDL National Science Digital Library

The Code Project is an online repository of free tutorials, source code, and articles about a wide variety of programming languages. Sections devoted to C++, HTML, DirectX, and .NET are among the resources available on the site. Discussion forums and message boards are excellent places for developers to get quick answers to their questions from other members of the community (this requires a short registration). Featured articles and industry news keep the site up-to-date. There are some advertisements on the site, but they do not detract from the content.

2007-07-25

407

Nonlinear, Nonbinary Cyclic Group Codes.  

National Technical Information Service (NTIS)

New cyclic group codes of length 2(exp m) - 1 over (m - j)-bit symbols are introduced. These codes can be systematically encoded and decoded algebraically. The code rates are very close to Reed-Solomon (RS) codes and are much better than Bose-Chaudhuri-Ho...

G. Solomon

1992-01-01

408

Coding Rules for Amino Acids in the Genetic Code: The Genetic Code is a Minimal Code of Mutational Deterioration  

Microsoft Academic Search

Coding rules for amino acids in the genetic code are discussed from the point that the genetic code is a minimal code ofmutational deterioration. The global mutational deterioration(GMD) function is defined through several parameters describingsingle base mutations and amino acid distances. The problem ofsearching for the global minimum of the GMD function is discussedin some detail. From GMD minimization under

Liaofu Luo; Xiaoqin Li

2002-01-01

409

How English Spelling Codes Language.  

ERIC Educational Resources Information Center

This paper presents three viewpoints of the coding of language in English spelling: the classical view (that letters are a code for phonemes but that English spelling contains much irregularity), the revolutionary position (that letters do not code phonemes at all), and the eclectic view (that English spelling does code phonemes but that it also…

Downing, John

410

Automated searching for quantum subsystem codes  

SciTech Connect

Quantum error correction allows for faulty quantum systems to behave in an effectively error-free manner. One important class of techniques for quantum error correction is the class of quantum subsystem codes, which are relevant both to active quantum error-correcting schemes as well as to the design of self-correcting quantum memories. Previous approaches for investigating these codes have focused on applying theoretical analysis to look for interesting codes and to investigate their properties. In this paper we present an alternative approach that uses computational analysis to accomplish the same goals. Specifically, we present an algorithm that computes the optimal quantum subsystem code that can be implemented given an arbitrary set of measurement operators that are tensor products of Pauli operators. We then demonstrate the utility of this algorithm by performing a systematic investigation of the quantum subsystem codes that exist in the setting where the interactions are limited to two-body interactions between neighbors on lattices derived from the convex uniform tilings of the plane.

Crosswhite, Gregory M.; Bacon, Dave [Department of Physics, University of Washington, Seattle, Washington 98195 (United States)

2011-02-15

411

Error Floor Estimation of Long LDPC Codes on Partial Response Channels  

Microsoft Academic Search

The presence of error floor in low density parity check (LDPC) codes is of great concern for potential applications of LDPC codes to data storage channels, which require the error correcting code (ECC) to maintain the near-capacity error correcting performance at frame error rate as low as 10-12. In order to investigate the error floor of LDPC codes under partial

Xinde Hu; B. V. K. Vijaya Kumar; Zongwang Li; Richard Barndt

2007-01-01

412

Accumulate Repeat Accumulate Coded Modulation  

NASA Technical Reports Server (NTRS)

In this paper we propose an innovative coded modulation scheme called 'Accumulate Repeat Accumulate Coded Modulation' (ARA coded modulation). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes that are combined with high level modulation. Thus at the decoder belief propagation can be used for iterative decoding of ARA coded modulation on a graph, provided a demapper transforms the received in-phase and quadrature samples to reliability of the bits.

Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

2004-01-01

413

High rate concatenated coding systems using bandwidth efficient trellis inner codes  

NASA Technical Reports Server (NTRS)

High-rate concatenated coding systems with bandwidth-efficient trellis inner codes and Reed-Solomon (RS) outer codes are investigated for application in high-speed satellite communication systems. Two concatenated coding schemes are proposed. In one the inner code is decoded with soft-decision Viterbi decoding, and the outer RS code performs error-correction-only decoding (decoding without side information). In the other, the inner code is decoded with a modified Viterbi algorithm, which produces reliability information along with the decoded output. In this algorithm, path metrics are used to estimate the entire information sequence, whereas branch metrics are used to provide reliability information on the decoded sequence. This information is used to erase unreliable bits in the decoded output. An errors-and-erasures RS decoder is then used for the outer code. The two schemes have been proposed for high-speed data communication on NASA satellite channels. The rates considered are at least double those used in current NASA systems, and the results indicate that high system reliability can still be achieved.

Deng, Robert H.; Costello, Daniel J., Jr.

1989-01-01

414

Esophagus Coding Guidelines  

Cancer.gov

Coding Guidelines ESOPHAGUS C150-C155, C158-C159 Primary Site There are two systems that divide the esophagus into three subsites. The first system divides the esophagus into the upper third, middle third, and lower third. The second system describes

415

Bone Coding Guidelines  

Cancer.gov

Coding Guidelines BONES, JOINTS, AND ARTICULAR CARTILAGE C400–C419 PERIPHERAL NERVES AND AUTONOMIC NERVOUS SYSTEM C470–C479 CONNECTIVE, SUBCUTANEOUS, AND OTHER SOFT TISSUES C490–C499 (Except for M9750, 9760-9764, 9800-9820, 9826, 9831-9920, 9931-9992)

416

Electromagnetic particle simulation codes  

Microsoft Academic Search

Electromagnetic particle simulations solve the full set of Maxwell's equations. They thus include the effects of self-consistent electric and magnetic fields, magnetic induction, and electromagnetic radiation. The algorithms for an electromagnetic code which works directly with the electric and magnetic fields are described. The fields and current are separated into transverse and longitudinal components. The transverse E and B fields

P. L. Pritchett

1985-01-01

417

Larynx Surgery Codes  

Cancer.gov

Larynx C320–C329 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967, 9975-9992) Codes 00 None; no surgery of primary site; autopsy ONLY 10 Local tumor destruction, NOS 11 Photodynamic therapy (PDT) 12 Electrocautery;

418

Skin Surgery Codes  

Cancer.gov

Ski n C440–C449 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967, 9975-9992) Codes 00 None; no surgery of primary site; autopsy ONLY 10 Local tumor destruction, NOS 11 Photodynamic therapy (PDT) 12 Electrocautery;

419

George Washington's Secret Code  

NSDL National Science Digital Library

In this online interactive, learners decipher codes used by George Washington to safeguard messages during the American Revolution. Learners use a key to decode an excerpt from "Rules of Civility & Decent Behaviour in Company and Conversation," which Washington copied as a writing exercise when he was a teenager and historians believed influenced the development of his character.

Service, National P.

2011-08-20

420

Cooperation diversity through coding  

Microsoft Academic Search

We propose a new user cooperation scheme for wireless communications in which we combine cooperation with existing channel coding methods. Simulation results show a significant improvement in the BER for both users, even when the channel between them is poor, or when they have significantly different channel qualities to the base station.

Todd E. Hunter; Aria Nosratinia

2002-01-01

421

Pharynx Surgery Codes  

Cancer.gov

Pharynx Tonsil C090–C099, Oropharynx C100–C109, Nasopharynx C110–C119 Pyriform Sinus C129, Hypopharynx C130–C139, Pharynx C140 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967, 9975-9992) Codes 00 None; no surgery

422

Building Codes and Regulations.  

ERIC Educational Resources Information Center

The hazard of fire is of great concern to libraries due to combustible books and new plastics used in construction and interiors. Building codes and standards can offer architects and planners guidelines to follow but these standards should be closely monitored, updated, and researched for fire prevention. (DS)

Fisher, John L.

423

Phonological Coding in Prereaders.  

ERIC Educational Resources Information Center

To examine changes in phonetic coding two age groups of 40 preschoolers were shown rhyming and nonrhyming letter sets. Recall was measured by oral free recall (testing item memory) and serial reconstruction (testing order memory). A large phonetic similarity effect was present in both groups with no developmental changes in the effect magnitude.…

Lean, Debra S.; Arbuckle, Tannis Y.

1984-01-01

424

Relative Iris Codes  

Microsoft Academic Search

This paper proposes a new scheme to generate iris codes based on relative measure of local iris texture. The local characteristic of iris texture is analyzed using 2D Gabor wavelets. Twelve Gabor kernels, four frequencies and three orientations, are constructed and convoluted with an iris image. To inherit relationship of local iris texture among pixels, Gabor magnitude and phase of

Peeranat Thoonsangngam; Somying Thainimit; Vutipong Areekul

2007-01-01

425

Dress Codes. Legal Brief.  

ERIC Educational Resources Information Center

As illustrated by two recent decisions, the courts in the past decade have demarcated wide boundaries for school officials considering dress codes, whether in the form of selective prohibitions or required uniforms. Administrators must warn the community, provide legitimate justification and reasonable clarity, and comply with state law. (MLH)

Zirkel, Perry A.

2000-01-01

426

Student Dress Codes.  

ERIC Educational Resources Information Center

School officials see a need for regulations that prohibit disruptive and inappropriate forms of expression and attire; students see these regulations as unwanted restrictions on their freedom. This paper reviews court litigation involving constitutional limitations on school authority, dress and hair codes, state law constraints, and school…

Uerling, Donald F.

427

Lung Coding Guidelines  

Cancer.gov

Coding Guidelines LUNG C340–C349 Primary Site C340 Main bronchus Carina Hilum Bronchus intermedius C341 Upper lobe, lung Lingula Apex Pancoast tumor C342 Middle lobe, lung (Right lung only) C343 Lower lobe, lung Base C348

428

Ovary Surgery Codes  

Cancer.gov

Ovary C569 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967, 9975-9992) Codes 00 None; no surgery of primary site; autopsy ONLY 17 Local tumor destruction, NOS No specimen sent to pathology from surgical event

429

Skin Surgery Codes  

Cancer.gov

Skin C440–C449 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967, 9975-9992) Codes 00 None; no surgery of primary site; autopsy ONLY 10 Local tumor destruction, NOS 11 Photodynamic therapy (PDT) 12 Electrocautery;

430

Colon Surgery Codes  

Cancer.gov

C olon C180–C189 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967, 9975-9992) Code removal/surgical ablation of single or multiple liver metastases under the data item Surgical Procedure/Other Site (NAACCR Item

431

Parotid Surgery Codes  

Cancer.gov

Parotid and Other Unspecified Glands Parotid Gland C079, Major Salivary Glands C080–C089 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967, 9975-9992) Codes 00 None; no surgery of primary site; autopsy ONLY

432

Esophagus Surgery Codes  

Cancer.gov

Esophagus C150–C159 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967, 9975-9992) Codes 00 None; no surgery of primary site; autopsy ONLY 10 Local tumor destruction, NOS 11 Photodynamic therapy (PDT) 12

433

Code Optimization Techniques  

SciTech Connect

Computers transfer data in a number of different ways. Whether through a serial port, a parallel port, over a modem, over an ethernet cable, or internally from a hard disk to memory, some data will be lost. To compensate for that loss, numerous error detection and correction algorithms have been developed. One of the most common error correction codes is the Reed-Solomon code, which is a special subset of BCH (Bose-Chaudhuri-Hocquenghem) linear cyclic block codes. In the AURA project, an unmanned aircraft sends the data it collects back to earth so it can be analyzed during flight and possible flight modifications made. To counter possible data corruption during transmission, the data is encoded using a multi-block Reed-Solomon implementation with a possibly shortened final block. In order to maximize the amount of data transmitted, it was necessary to reduce the computation time of a Reed-Solomon encoding to three percent of the processor's time. To achieve such a reduction, many code optimization techniques were employed. This paper outlines the steps taken to reduce the processing time of a Reed-Solomon encoding and the insight into modern optimization techniques gained from the experience.

MAGEE,GLEN I.

2000-08-03

434

Decode de Code  

NSDL National Science Digital Library

In this activity, users must decode a scientific quote that has been encoded by the computer. The computer will generate an "alphabet" (either random or rotated) and then substitute every letter of the real quote with the computer generated alphabet's letter. To decode the code, you must look for patterns of letters and then substitute guesses for the real letters.

435

EGS5 Code System.  

National Technical Information Service (NTIS)

The EGS (Electron-Gamma Shower) code system is a general purpose package for the Monte Carlo simulation of the coupled transport of electrons and photons in an arbitrary geometry for particles with energies above a few keV up to several hundred GeV (depen...

2005-01-01

436

Raptor network video coding  

Microsoft Academic Search

In this paper, we consider the problem of streaming video information on lossy packet networks with path and source diversity, such as wireless mesh networks or more generally overlay architectures. We propose to distribute the video information between several streaming servers and to implement network coding in the forwarding peers in order to increase the quality of the video decoded

Nikolaos Thomos; Pascal Frossard

2007-01-01

437

Matlab code for \\  

Microsoft Academic Search

Code to find the solution to the heterogeneous agents model in Den Haan, Judd and Juillard (2008). To solve for the individual policy rules, we use an Euler-equation method iterating on a grid of prespecified points. To compute the aggregate law of motion, we use the stochastic-simulation approach of Krusell and Smith (1998).

Lilia Maliar; Fernando Valli; Seguei Maliar

2009-01-01

438

MATLAB code for SAWS  

Microsoft Academic Search

A planar harmonic Green's matrix function is widely exploited in theory of SAW devices. In many practical cases, the papal approximation to this function is sufficient for analysis. Here, a number of numerical codes are presented in MATLAB for fundamental analysis of surface acoustic waves in piezoelectric crystals, including: derivation of Stroh matrix for given material and Euler angles, visualization

E. Danicki

1999-01-01

439

CODE OF FEDERAL REGULATIONS  

EPA Science Inventory

The Code of Federal Regulations (CFR) is an annually revised codification of the general and permanent rules published in the Federal Register by the executive departments and agencies of the Federal Government. The CFR is divided into 50 titles which represent broad areas subje...

440

Code Games for Kids  

NSDL National Science Digital Library

This interactive game for children promotes pattern recognition by identifying the missing numbers in a pattern displayed on a safe lock. Players drag number tiles into the gaps and if successful unlock the safe and move onto a different challenge. There are two practice rounds and then ten codes to crack.

2013-01-01

441

Image plane coded aperture for terahertz imaging  

NASA Astrophysics Data System (ADS)

In the absence of detector arrays, a single pixel coupled with an image plane coded aperture has been shown to be a practical solution to imaging problems in the terahertz and sub-millimeter wave domains. The authors demonstrate two laboratory, real-time, two-dimensional, sub-millimeter wave imagers that are based on an image plane coded aperture. These active imaging systems consist of a heterodyne source and receiver pair, image forming optics, a coded aperture, data acquisition hardware, and image reconstruction software. In one of the configurations, the target is measured in transmission, while in the other it is measured in reflection. In both configurations, images of the targets are formed on the coded aperture, and linear measurements of the image are acquired as the aperture patterns change. Once a sufficient number of linearly independent measurements are obtained, the image is reconstructed by solving a system of linear equations that is generated from the aperture patterns and the corresponding measurements. The authors show that for image sizes envisioned for many current applications, this image reconstruction technique is computationally efficient and can be implemented in real time. Measurements are collected with these systems, and the reconstruction results are presented and discussed.

Furxhi, Orges; Jacobs, Eddie L.; Preza, Chrysanthe

2012-09-01

442

TACO: a finite element heat transfer code  

SciTech Connect

TACO is a two-dimensional implicit finite element code for heat transfer analysis. It can perform both linear and nonlinear analyses and can be used to solve either transient or steady state problems. Either plane or axisymmetric geometries can be analyzed. TACO has the capability to handle time or temperature dependent material properties and materials may be either isotropic or orthotropic. A variety of time and temperature dependent loadings and boundary conditions are available including temperature, flux, convection, and radiation boundary conditions and internal heat generation. Additionally, TACO has some specialized features such as internal surface conditions (e.g., contact resistance), bulk nodes, enclosure radiation with view factor calculations, and chemical reactive kinetics. A user subprogram feature allows for any type of functional representation of any independent variable. A bandwidth and profile minimization option is also available in the code. Graphical representation of data generated by TACO is provided by a companion post-processor named POSTACO. The theory on which TACO is based is outlined, the capabilities of the code are explained, the input data required to perform an analysis with TACO are described. Some simple examples are provided to illustrate the use of the code.

Mason, W.E. Jr.

1980-02-01

443

The TESS (Tandem Experiment Simulation Studies) computer code user's manual  

SciTech Connect

TESS (Tandem Experiment Simulation Studies) is a one-dimensional, bounded particle-in-cell (PIC) simulation code designed to investigate the confinement and transport of plasma in a magnetic mirror device, including tandem mirror configurations. Mirror plasmas may be modeled in a system which includes an applied magnetic field and/or a self-consistent or applied electrostatic potential. The PIC code TESS is similar to the PIC code DIPSI (Direct Implicit Plasma Surface Interactions) which is designed to study plasma transport to and interaction with a solid surface. The codes TESS and DIPSI are direct descendants of the PIC code ES1 that was created by A. B. Langdon. This document provides the user with a brief description of the methods used in the code and a tutorial on the use of the code. 10 refs., 2 tabs.

Procassini, R.J. (California Univ., Berkeley, CA (USA). Dept. of Nuclear Engineering); Cohen, B.I. (Lawrence Livermore National Lab., CA (USA))

1990-06-01

444

The AMOS (Azimuthal Mode Simulator) code  

SciTech Connect

AMOS is a newly developed computer code that is finding application in the design of accelerator cavities. The program simulates the temporal evolution of electromagnetic fields in rotationally symmetric structures. An explicit Fourier series expansion is assumed in the azimuthal coordinate, which allows different multipole modes to be simulated independently. Nonuniform electrical properties (epsilon, ..mu.., sigma) are permitted, and both impedance and radiation boundary conditions are available. A geometric editor (DRAGON) allows for simple and rapid development/modification of models, and a direct CAD system-DRAGON data link is being used to facilitate the study of existing and developmental linac accelerator cells. A wakefield postprocessor (ANDY) allows the calculation of wake potentials, cavity impedances, etc., from AMOS simulation data. Code verification has consisted of comparisons with exact and approximate analytic results for simple geometries. 6 refs., 3 figs.

DeFord, J.F.; Craig, G.D.; McLeod, R.

1989-03-10

445

Instructional Materials in Independent Living.  

ERIC Educational Resources Information Center

This annotated list of 103 instructional materials for use in an independent living program focused on personal, social, and community adjustment of those with special needs is cross referenced using a subject index that lists skill areas within a fourteen-category system. Document descriptions are arranged alphabetically by author and include…

Smith, Bradley C.; Fry, Ronald R.

446

ALGEBRAIC OVERCOMPLETE INDEPENDENT COMPONENT ANALYSIS  

Microsoft Academic Search

Algebraic Independent Component Analysis (AICA) is a new ICA algorithm that exploits algebraic operations and vector- distance measures to estimate the unknown mixing matrix in a scaled algebraic domain. AICA possesses stability and convergence properties similar to earlier proposed geometic ICA (geo-ICA) algorithms, however, the choice of the proposed algebraic measures in AICA has several advantages. Firstly, it leads to

Khurram Waheed; Fathi M. Salem

447

Independent Study Project, Topic: Topology.  

ERIC Educational Resources Information Center

Using this guide and the four popular books noted in it, a student, working independently, will learn about some of the classical ideas and problems of topology: the Meobius strip and Klein bottle, the four color problem, genus of a surface, networks, Euler's formula, and the Jordan Curve Theorem. The unit culminates in a project of the students'…

Notre Dame High School, Easton, PA.

448

Independent Component Analysis of Textures.  

National Technical Information Service (NTIS)

A common method for texture representation is to use the marginal probability densities over the outputs of a set of multi-orientation, multi-scale filters as a description of the texture. We propose a technique, based on Independent Components Analysis, ...

R. Manduchi J. Portilla

2000-01-01

449

Haptic Tracking Permits Bimanual Independence  

ERIC Educational Resources Information Center

This study shows that in a novel task--bimanual haptic tracking--neurologically normal human adults can move their 2 hands independently for extended periods of time with little or no training. Participants lightly touched buttons whose positions were moved either quasi-randomly in the horizontal plane by 1 or 2 human drivers (Experiment 1), in…

Rosenbaum, David A.; Dawson, Amanda A.; Challis, John H.

2006-01-01

450

Text-independent speaker identification  

Microsoft Academic Search

We describe current approaches to text-independent speaker identification based on probabilistic modeling techniques. The probabilistic approaches have largely supplanted methods based on comparisons of long-term feature averages. The probabilistic approaches have an important and basic dichotomy into nonparametric and parametric probability models. Nonparametric models have the advantage of being potentially more accurate models (though possibly more fragile) while parametric models

H. Gish; M. Schmidt

1994-01-01

451

Quasi-Cyclic LDPC Codes for the Magnetic Recording Channel: Code Design and VLSI Implementation  

Microsoft Academic Search

By implementing a field-programmable gate array (FPGA)-based simulator, we investigate the performance of randomly constructed high-rate quasi-cyclic (QC) low-density parity-check (LDPC) codes for the magnetic recording channel at very low block sector error rates. On the basis of extensive simulations, we conjecture guidelines for designing randomly constructed high-rate regular QC-LDPC codes with low error floor for the magnetic recording channel.

Hao Zhong; Tong Zhong; Erich F. Haratsch

2007-01-01

452

Multiphysics Code Demonstrated for Propulsion Applications  

NASA Technical Reports Server (NTRS)

The utility of multidisciplinary analysis tools for aeropropulsion applications is being investigated at the NASA Lewis Research Center. The goal of this project is to apply Spectrum, a multiphysics code developed by Centric Engineering Systems, Inc., to simulate multidisciplinary effects in turbomachinery components. Many engineering problems today involve detailed computer analyses to predict the thermal, aerodynamic, and structural response of a mechanical system as it undergoes service loading. Analysis of aerospace structures generally requires attention in all three disciplinary areas to adequately predict component service behavior, and in many cases, the results from one discipline substantially affect the outcome of the other two. There are numerous computer codes currently available in the engineering community to perform such analyses in each of these disciplines. Many of these codes are developed and used in-house by a given organization, and many are commercially available. However, few, if any, of these codes are designed specifically for multidisciplinary analyses. The Spectrum code has been developed for performing fully coupled fluid, thermal, and structural analyses on a mechanical system with a single simulation that accounts for all simultaneous interactions, thus eliminating the requirement for running a large number of sequential, separate, disciplinary analyses. The Spectrum code has a true multiphysics analysis capability, which improves analysis efficiency as well as accuracy. Centric Engineering, Inc., working with a team of Lewis and AlliedSignal Engines engineers, has been evaluating Spectrum for a variety of propulsion applications including disk quenching, drum cavity flow, aeromechanical simulations, and a centrifugal compressor flow simulation.

Lawrence, Charles; Melis, Matthew E.

1998-01-01

453

Adaptive Modulation and Code Channel Elimination for Vector Coding System  

NASA Astrophysics Data System (ADS)

Vector coding (VC) is a kind of eigen mode transmission scheme which is typically considered in MIMO systems. In VC systems, several code channels corresponding to the eigenvalues of the channel matrix are created. However, any code channels with low eigenvalues will cause a degradation in performance. In this paper, adaptive modulation and coding (AMC) for a VC system is proposed. In addition to AMC, the number of code channels is adaptively changed by code channel elimination. We show that the BER performance of VC is better than that of MMSE. Secondly, we also show the throughput performance of the proposed scheme is improved compared with the maximum throughput of each individual MCS.

Takeda, Daisuke; Nakagawa, Masao

454

Design of Multiplexed Coding for User Cooperation  

Microsoft Academic Search

We consider the multiplexed coding design for cooperative communications. The ideal multiplexed coding, which outperforms the superposition coding in theory, is difficult to implement with practical error-correction codes. We therefore introduce a partially multiplexed (PMP) coding scheme to approach the performance of fully multiplexed coding scheme. We then design the PMP coding using irregular repeat accumulate (IRA) codes. We also

Guosen Yue; Xiaodong Wang; Mohammad Madihian

2006-01-01

455

Group independent component analysis of MR spectra  

PubMed Central

This study investigates the potential of independent component analysis (ICA) to provide a data-driven approach for group level analysis of magnetic resonance (MR) spectra. ICA collectively analyzes data to identify maximally independent components, each of which captures covarying resonances, including those from different metabolic sources. A comparative evaluation of the ICA approach with the more established LCModel method in analyzing two different noise-free, artifact-free, simulated data sets of known compositions is presented. The results from such ideal simulations demonstrate the ability of data-driven ICA to decompose data and accurately extract components resembling modeled basis spectra from both data sets, whereas the LCModel results suffer when the underlying model deviates from assumptions, thus highlighting the sensitivity of model-based approaches to modeling inaccuracies. Analyses with simulated data show that independent component weights are good estimates of concentrations, even of metabolites with low intensity singlet peaks, such as scyllo-inositol. ICA is also applied to single voxel spectra from 193 subjects, without correcting for baseline variations, line-width broadening or noise. The results provide evidence that, despite the presence of confounding artifacts, ICA can be used to analyze in vivo spectra and extract resonances of interest. ICA is a promising technique for decomposing MR spectral data into components resembling metabolite resonances, and therefore has the potential to provide a data-driven alternative to the use of metabolite concentrations derived from curve-fitting individual spectra in making group comparisons.

Kalyanam, Ravi; Boutte, David; Gasparovic, Chuck; Hutchison, Kent E; Calhoun, Vince D

2013-01-01

456

Progress in cultivation-independent phyllosphere microbiology.  

PubMed

Most microorganisms of the phyllosphere are nonculturable in commonly used media and culture conditions, as are those in other natural environments. This review queries the reasons for their 'noncultivability' and assesses developments in phyllospere microbiology that have been achieved cultivation independently over the last 4 years. Analyses of total microbial communities have revealed a comprehensive microbial diversity. 16S rRNA gene amplicon sequencing and metagenomic sequencing were applied to investigate plant species, location and season as variables affecting the composition of these communities. In continuation to culture-based enzymatic and metabolic studies with individual isolates, metaproteogenomic approaches reveal a great potential to study the physiology of microbial communities in situ. Culture-independent microbiological technologies as well advances in plant genetics and biochemistry provide methodological preconditions for exploring the interactions between plants and their microbiome in the phyllosphere. Improving and combining cultivation and culture-independent techniques can contribute to a better understanding of the phyllosphere ecology. This is essential, for example, to avoid human-pathogenic bacteria in plant food. PMID:24003903

Müller, Thomas; Ruppel, Silke

2014-01-01

457

Independency of myocardial stunning of endothelial stunning?  

Microsoft Academic Search

Background and objective\\u000a   Vascular endothelial cells play an important role in the control of vascular tone. The reasons for coronary endothelial dysfunction\\u000a are complex and may involve ischemia\\/reperfusion injury. We investigated whether endothelial, smooth muscle, and myocardial\\u000a dysfunction are independent phenomena.\\u000a \\u000a \\u000a \\u000a \\u000a Methods\\u000a   Rabbit hearts were rapidly excised without intermittent ischemia, connected to a modified Langendorff apparatus, and perfused\\u000a with a

S. C. Garcia; V. Pomblum; E. Gams; M. R. Langenbach; J. D. Schipke

2007-01-01

458

Cooperative Multiuser Relay Communication with Superposition Coding  

NASA Astrophysics Data System (ADS)

Cooperative relaying, while effective in mitigating fading effects, might reduce the overall network throughput since its overhead such as additional time slot and frequency band can be significant. In order to overcome this problem, this paper proposes a superposition coding based cooperative relay scheme to provide reliable transmission with little or no overhead. This scheme exploits the superimposed messages for users in the network to achieve the simultaneous transmission of two or more independent data streams. This scheme reduces the number of transmission phases to the same as that of conventional cooperative relay schemes. The symbol error performance of the proposed scheme is analyzed and simulated.

Whang, Roderick Jaehoon; Portugal, Sherlie; Hwang, Intae; Liu, Huaping

459

Preliminary benchmarking of the HELIOS code for hexagonal lattice reactors  

Microsoft Academic Search

Los Alamos National Laboratory (LANL), under the sponsorship of the US Department of Energy, has been performing independent safety evaluations for the Savannah River National Laboratory's (SNL's) K Reactor. The structure of the K Reactor core is quite different from that of commercial reactors, and few codes developed for commercial reactors have the capabilities required for analysis of the K

J. R. Streetman; J. L. Sapir; R. J. J. Stammler

1992-01-01

460

Automatic differentiation of advanced CFD codes for multidisciplinary design  

Microsoft Academic Search

Automated multidisciplinary design of aircraft and other flight vehicles requires the optimization of complex performance objectives with respect to a number of design parameters and constraints. The effect of these independent design variables on the system performance criteria can be quantified in terms of sensitivity derivatives which must be calculated and propagated by the individual discipline simulation codes. Typical advanced

C. Bischof; G. Corliss; A. Griewank; L. Green; K. Haigler; P. Newman

1992-01-01

461

Efficient error estimating coding: feasibility and applications  

Microsoft Academic Search

Motivated by recent emerging systems that can leverage partially correct packets in wireless networks, this paper investigates the novel concept of error estimating codes (EEC). Without correcting the errors in the packet, EEC enables the receiver of the packet to estimate the packet's bit error rate, which is perhaps the most important meta-information of a partially correct packet. Our EEC

Binbin Chen; Ziling Zhou; Yuda Zhao; Haifeng Yu

2010-01-01

462

Optimal Compression Plane for Efficient Video Coding  

Microsoft Academic Search

All existing video coding standards developed so far deem video as a sequence of natural frames (formed in the XY plane), and treat spatial redundancy (redundancy along X and Y directions) and temporal redundancy (redundancy along T direction) differently and separately. In this paper, we investigate into a new compression (redundancy reduction) method for video in which the frames are

Anmin Liu; Weisi Lin; Manoranjan Paul; Fan Zhang; Chenwei Deng

2011-01-01

463

Perceptual video coding: Challenges and approaches  

Microsoft Academic Search

Investigation on the human perception can play an important role in video signal processing. Recently, there has been great interest in incorporating the human perception in video coding systems to enhance the perceptual quality of the represented visual signal. However, the limited understanding of the human visual system and high complexity of computational models of human visual system make it

Zhenzhong Chen; Weisi Lin; King Ngi Ngan

2010-01-01

464

A combined Monte Carlo diode simulation code  

Microsoft Academic Search

A collisional Monte Carlo electron transport model has been combined with an existing relativistic electron beam diode simulation code to investigate the effect of electron material interactions on diode performance. The effects of electron scattering and deposition in various anode materials on the electron beam profile are detailed. Simulations of two enhanced electron deposition experiments are described.

J. P. Quintenz; M. M. Widner

1980-01-01

465

Quantization for Distributed Testing of Independence.  

National Technical Information Service (NTIS)

We consider the problem of distributed test of statistical independence under communication constraints. While independence test is frequently encountered in various applications, distributed independence test is particularly useful for events detection i...

B. Chen J. Matyjas M. Chen W. Liu

2010-01-01

466

29 CFR 785.30 - Independent training.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Independent training. 785.30 Section 785...Principles Lectures, Meetings and Training Programs § 785.30 Independent training. Of course, if an employee on his own initiative attends an independent...

2010-07-01

467

29 CFR 785.30 - Independent training.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Independent training. 785.30 Section 785...Principles Lectures, Meetings and Training Programs § 785.30 Independent training. Of course, if an employee on his own initiative attends an independent...

2009-07-01

468

A Comparative Study on Seismic Analysis of Bangladesh National Building Code (BNBC) with Other Building Codes  

NASA Astrophysics Data System (ADS)

Tectonic framework of Bangladesh and adjoining areas indicate that Bangladesh lies well within an active seismic zone. The after effect of earthquake is more severe in an underdeveloped and a densely populated country like ours than any other developed countries. Bangladesh National Building Code (BNBC) was first established in 1993 to provide guidelines for design and construction of new structure subject to earthquake ground motions in order to minimize the risk to life for all structures. A revision of BNBC 1993 is undergoing to make this up to date with other international building codes. This paper aims at the comparison of various provisions of seismic analysis as given in building codes of different countries. This comparison will give an idea regarding where our country stands when it comes to safety against earth quake. Primarily, various seismic parameters in BNBC 2010 (draft) have been studied and compared with that of BNBC 1993. Later, both 1993 and 2010 edition of BNBC codes have been compared graphically with building codes of other countries such as National Building Code of India 2005 (NBC-India 2005), American Society of Civil Engineering 7-05 (ASCE 7-05). The base shear/weight ratios have been plotted against the height of the building. The investigation in this paper reveals that BNBC 1993 has the least base shear among all the codes. Factored Base shear values of BNBC 2010 are found to have increased significantly than that of BNBC 1993 for low rise buildings (?20 m) around the country than its predecessor. Despite revision of the code, BNBC 2010 (draft) still suggests less base shear values when compared to the Indian and American code. Therefore, this increase in factor of safety against the earthquake imposed by the proposed BNBC 2010 code by suggesting higher values of base shear is appreciable.

Bari, Md. S.; Das, T.

2013-09-01

469

Performance limits of coded diversity methods for transmitter antenna arrays  

Microsoft Academic Search

Several aspects of the design and optimization of coded multiple-antenna transmission diversity methods for slowly time-varying channels are explored from an information-theoretic perspective. Both optimized vector-coded systems, which can achieve the maximum possible performance, and suboptimal scalar-coded systems, which reduce complexity by exploiting suitably designed linear precoding, are investigated. The achiev- able rates and associated outage characteristics of th