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1

SOCRATES: a highly efficient automatic test pattern generation system  

Microsoft Academic Search

An automatic test pattern generation system, SOCRATES, is presented. SOCRATES includes several novel concepts and techniques that significantly improve and accelerate the automatic test pattern generation process for combinational and scan-based circuits. Based on the FAN algorithm, improved implication, sensitization, and multiple backtrace procedures are described. The application of these techniques leads to a considerable reduction of the number of

Michael H. Schulz; Erwin Trischler; Thomas M. Sarfert

1988-01-01

2

Cellular automata-based test pattern generators with phase shifters  

Microsoft Academic Search

The paper presents a novel, comprehensive and systematic methodology, which can be used to automate synthesis of cellular automata-based test pattern generators with phase shifters. First, a very fast and simple simulation framework is proposed to either verify or generate maximum-length linear finite state machines such as cellular automata or linear feedback shift registers. Subsequently, a new framework is presented

Grzegorz Mrugalski; Janusz Rajski; Jerzy Tyszer

2000-01-01

3

A low power dynamic pseudo random bit generator for test pattern generation  

Microsoft Academic Search

Pseudo random bit generator is widely used in BIST for test pattern generation. Typical pseudo random bit generator adopts linear feedback shift register (LFSR) as its basic circuit. Dynamic LFSR (DLFSR[1]) which has better cryptographic properties with respect to typical LFSR consumes more power. This paper forwards a low power DLFSR (LDLFSR) circuit which achieves comparable performance with less power

Li-gang Hou; Xiao-hong Peng; Wu-chen Wu

2008-01-01

4

Test Pattern Generation for Realistic Bridge Faults in CMOS ICs  

Microsoft Academic Search

Two approaches have been used to balance the costof generating effective tests for IC's and the need toincrease the quality level of shipped IC's. The first approachfavors using high-level fault models to reducetest generation costs, and the second approach favorsthe use of low-level, technology-specific fault modelsthat lead to high test generation costs, but increaseddefect coverage in the tested circuits. In

F. Joel Ferguson; Tracy Larrabee

1991-01-01

5

Pattern generation.  

PubMed

Central pattern generators are neuronal ensembles capable of producing the basic spatiotemporal patterns underlying 'automatic' movements (e.g. locomotion, respiration, swallowing and defense reactions), in the absence of peripheral feedback. Different experimental approaches, from classical electrophysiological and pharmacological methods to molecular and genetic ones, have been used to understand the cellular and synaptic bases of central pattern generator organization and reconfiguration of generator operation in behaviorally relevant contexts. Recently, it has been shown that the high reliability and flexibility of central pattern generators is determined by their redundant organization. Everything that is crucial for generator operation is determined by a number of complementary mechanisms acting in concert; however, various mechanisms are weighted differently in determining different aspects of central pattern generator operation. PMID:9464971

Arshavsky, Y I; Deliagina, T G; Orlovsky, G N

1997-12-01

6

Pattern Generator for Bench Test of Digital Boards  

NASA Technical Reports Server (NTRS)

All efforts to develop electronic equipment reach a stage where they need a board test station for each board. The SMAP digital system consists of three board types that interact with each other using interfaces with critical timing. Each board needs to be tested individually before combining into the integrated digital electronics system. Each board needs critical timing signals from the others to be able to operate. A bench test system was developed to support test of each board. The test system produces all the outputs of the control and timing unit, and is delivered much earlier than the timing unit. Timing signals are treated as data. A large file is generated containing the state of every timing signal at any instant. This file is streamed out to an IO card, which is wired directly to the device-under-test (DUT) input pins. This provides a flexible test environment that can be adapted to any of the boards required to test in a standalone configuration. The problem of generating the critical timing signals is then transferred from a hardware problem to a software problem where it is more easily dealt with.

Berkun, Andrew C.; Chu, Anhua J.

2012-01-01

7

Pattern Generator  

NSDL National Science Digital Library

This Java applet activity allows the learner to recognize patterns and extend them in a sequence of shapes, numbers, or letters. A student can choose from three levels of difficulty and then after determining the pattern, fills in the missing pieces from the right side of the board into their appropriate places in the pattern, shown on the left. There are four tabs for support: Learner, Activity, Help and Instructor and links to other related resources.

2005-01-01

8

A Modified Clock Scheme for a Low Power BIST Test Pattern Generator  

Microsoft Academic Search

In this paper, we present a new low power test-per-clock BIST test pattern generator that provides test vectors which can reduce the switching activity during test operation. The proposed low power\\/energy BIST technique is based on a modified clock scheme for the TPG and the clock tree feeding the TPG. Numerous advantages can be found in applying such a technique.

Patrick Girard; Loïs Guiller; Christian Landrault; Serge Pravossoudovitch; Hans-joachim Wunderlich

2001-01-01

9

An on-chip march pattern generator for testing embedded memory cores  

Microsoft Academic Search

In this correspondence, we propose an effective approach to integrate 40 existing march algorithms into an embedded low hardware overhead test pattern generator to test the various kinds of word-oriented memory cores. Each march algorithm is characterized by several sets of up\\/down address orders, read\\/write signals, read\\/write data, and lengths of read\\/write operations. These characteristics are stored on chip so

Wei-lun Wang; Kuen-jong Lee; Jhing-fa Wang

2001-01-01

10

TIGUAN: Thread-Parallel Integrated Test Pattern Generator Utilizing Satisfiability ANalysis  

Microsoft Academic Search

We present the automatic test pattern generator TIGUAN basedonathread-parallelSATsolver.Duetoatightintegra- tionoftheSATengineintotheATPGalgorithmandacare- fully chosen mix of various optimization techniques, multi- million-gate industrial circuits are handled without aborts. TIGUAN supports both conventional single-stuck-at faults andsophisticatedconditionalmultiplestuck-atfaultswhich allowstogeneratepatternsfornon-standardfaultmodels. Second, redundant structures are increasingly used to en- hance circuit reliability and yield (16,17). A significant frac- tion of faults in these structures are not detectable. To

Alejandro Czutro; Ilia Polian; Matthew Lewis; Piet Engelke; Sudhakar M. Reddy; Bernd Becker

2009-01-01

11

Generating surface crack patterns  

Microsoft Academic Search

We present a method for generating surface crack patterns that appear in materials such as mud, ceramic glaze, and glass. To model these phenomena, we build upon existing physi- cally based methods. Our algorithm generates cracks from a stress field defined heuristi- cally over a triangle discretization of the surface. The simulation produces cracks by evolving this field over time.

Hayley N. Iben; James F. O'brien

2006-01-01

12

Generating surface crack patterns  

Microsoft Academic Search

We present a method for generating surface crack patterns that appear in materials such as mud, ceramic glaze, and glass. To model these phenomena, we build upon existing physically based methods. Our algorithm generates cracks from a stress field defined heuristically over a triangle discretization of the surface. The simulation produces cracks by evolving this field over time. The user

Hayley N. Iben; James F. O’Brien

2009-01-01

13

A stochastic pattern generation and optimization framework for variation-tolerant, power-safe scan test  

Microsoft Academic Search

Process variation is an increasingly dominant phenomenon affecting both power and performance in sub-100 nm technologies. Cost considerations often do not permit over-designing the power supply infrastructure for test mode, considering the worst-case scenario. Test application must not over-exercise the power supply grids, lest the tests will damage the device or lead to false test failures. The problem of debugging

V. R. Devanathan; C. P. Ravikumar; V. Kamakoti

2007-01-01

14

Mining frequent patterns without candidate generation  

Microsoft Academic Search

Mining frequent patterns in transaction databases, time-series databases, and many other kinds of databases has been studied popularly in data mining research. Most of the previous studies adopt an Apriori-like candidate set generation-and-test approach. However, candidate set generation is still costly, especially when there exist prolific patterns and\\/or long patterns.In this study, we propose a novel frequent pattern tree (FP-tree)

Jiawei Han; Jian Pei; Yiwen Yin

2000-01-01

15

Patterns Generate Architectures  

Microsoft Academic Search

We need ways to describe designs that communicate the reasons for our design decisions, not just the results. Design patterns have been proposed as ways of communicating design information. This paper shows that patterns can be used to derive an architecture from its problem statement. The resulting description makes it easier to understand the purpose of the various architectural features.

Kent Beck; Ralph E. Johnson

1994-01-01

16

Compositional dynamic test generation  

Microsoft Academic Search

Dynamic test generation is a form of dynamic program analysis that attempts to compute test inputs to drive a program along a specific program path. Directed Automated Random Testing, or DART for short, blends dynamic test generation with model checking techniques with the goal of systematically executing all feasible program paths of a program while detecting various types of errors

Patrice Godefroid

2007-01-01

17

Invertebrate central pattern generator circuits  

PubMed Central

There are now a reasonable number of invertebrate central pattern generator (CPG) circuits described in sufficient detail that a mechanistic explanation of how they work is possible. These small circuits represent the best-understood neural circuits with which to investigate how cell-to-cell synaptic connections and individual channel conductances combine to generate rhythmic and patterned output. In this review, some of the main lessons that have appeared from this analysis are discussed and concrete examples of circuits ranging from single phase to multiple phase patterns are described. While it is clear that the cellular components of any CPG are basically the same, the topology of the circuits have evolved independently to meet the particular motor requirements of each individual organism and only a few general principles of circuit operation have emerged. The principal usefulness of small systems in relation to the brain is to demonstrate in detail how cellular infrastructure can be used to generate rhythmicity and form specialized patterns in a way that may suggest how similar processes might occur in more complex systems. But some of the problems and challenges associated with applying data from invertebrate preparations to the brain are also discussed. Finally, I discuss why it is useful to have well-defined circuits with which to examine various computational models that can be validated experimentally and possibly applied to brain circuits when the details of such circuits become available.

Selverston, Allen I.

2010-01-01

18

Creative Test Generators  

ERIC Educational Resources Information Center

A brief description of a test generating program which generates questions concerning the Fortran programming language in a random but guided fashion and without resorting to an item bank.'' (Author/AK)

Vickers, F. D.

1973-01-01

19

A versatile programmable pattern generator.  

PubMed

A versatile visual pattern generator is described that can be programmed by a microcomputer and is developed as a part of a portable visual evoked potential analysis system. The hardware is contained on one printed circuit board (3" X 10", 7.5 X 25.5 cm) residing in an interface connector of a microcomputer (Apple II). The generator produces signals for commercial 50 Hz video monitors; a calibration procedure based on a photocell measurement corrects for the non-linear voltage intensity characteristic of the phosphor of the video monitor. PMID:3617543

Sportel, H; Smit, H W; Grimbergen, C A

1987-01-01

20

March Test Generation Revealed  

Microsoft Academic Search

Memory testing commonly faces two issues: the characterization of detailed and realistic fault models and the definition of time-efficient test algorithms. Among the different types of algorithms proposed for testing static random access memories, march tests have proven to be faster, simpler, and regularly structured. The majority of the published march tests have been manually generated. Unfortunately, the continuous evolution

Alfredo Benso; Alberto Bosio; Stefano Di Carlo; Giorgio Di Natale; Paolo Prinetto

2008-01-01

21

Starter/generator testing  

NASA Astrophysics Data System (ADS)

Sundstrand Aerospace and GE Aircraft Engines have studied the switched reluctance machine for use as an integral starter/generator for future aircraft engines. They have conducted an initial, low-power testing of the starter/generator, which is based on power inverters using IGBT-technology semiconductors, to verify its feasibility in the externally mounted version of the integral starter/generator. This preliminary testing of the 250-kW starter/generator reveals favorable results.

Anon

1994-10-01

22

Testing random number generators  

Microsoft Academic Search

So-called Random number generators on computersare deterministic functions producing a sequence of numberswhich should mimic a sample of i.i.d. U(0; 1) randomvariables. Two classes of tests are commonly applied tosuch generators. Firstly, the theoretical tests, which lookat the intrinsic structure of the generator to derive behavioralproperties of the sequence of points, usually overthe whole period. These theoretical tests are specific

Pierre L'Ecuyer

1992-01-01

23

Fastrac Gas Generator Testing  

NASA Technical Reports Server (NTRS)

A rocket engine gas generator component development test was recently conducted at the Marshall Space Flight Center. This gas generator was intended to power a rocket engine turbopump by the combustion of Lox and RP-1. The testing demonstrated design requirements for start sequence, wall compatibility, performance, and stable combustion. During testing the gas generator injector was modified to improve distribution of outer wall coolant and the igniter boss was modified to investigate the use of a pyrotechnic igniter, Expected chamber pressure oscillations at longitudinal acoustic modes were measured for three different chamber lengths tested. High amplitude discrete oscillations occurred in the chamber-alone configurations when chamber acoustic modes coupled with feed-system acoustics modes. For the full gas generator configuration, which included the turbine inlet manifold simulator, high amplitude oscillations occurred only at off-design very low power levels. This testing led to a successful gas generator design for the Fastrac 60,000 lb thrust engine.

Nesman, Tomas E.; Dennis, Jay

1999-01-01

24

Apparatus for Generating Nonlinear Pulse Patterns.  

National Technical Information Service (NTIS)

Apparatus for generating a plurality of nonlinear pulse patterns from a single linear pulse pattern. A first counter counts the pulses of the linear pulse pattern and a second counter counts the pulses of the nonlinear pulse pattern. A comparator compares...

N. M. I. Nakamura

1979-01-01

25

Hierarchical test pattern composition to testing a foveal imager ASIC  

NASA Astrophysics Data System (ADS)

The aim of this work is the test of an ASIC, intended for multiresolution images generation, with high fault coverage and low number of patterns, looking for the improvement of the results obtained with other tools. The circuit includes a embedded SRAM block used to implement several internal FIFO structures. This RAM block has been generated with the 'Memory Compiler Systems' supplied by AMS, and does not includes BIST logic, so the strategy was to generate and insert the BIST logic to completely test the RAM operation. The original test algorithm proposed by the foundry support center, has been modified for a thorough verification. Also, to achieve the controllability and observability of the shadow logic connected to the RAM outputs and inputs respectively, the necessary test logic around the embedded block has been inserted. Once the test of the RAM has been guaranteed the remaining logic needs to be tested. To accomplish this task the full scan path approach has been selected, and a hierarchical bottom-up methodology has been followed to generate the test patterns. The ATPG commercial tools ( Synopsys Test Compiler) has been used only to generate the patterns for the lowest level modules of the hierarchy tree. Making the appropriate design partitioning (basically defining the modules with registered outputs), the patterns for the upper level modules can be easily composed. Several appropriate configurations for this smart partitioning has been identified and defined. Using a simple composing technique we can obtain a considerable reduction above 37% in the number of patterns with a negligible fault coverage decrease and hardware overhead.

Gonzalez, Martin; Salinas, Jose R.; Coslado, Francisco J.; Camacho, Pelegrin; Sandoval, Francisco

2003-04-01

26

Apparatus for generating nonlinear pulse patterns  

DOEpatents

Apparatus for generating a plurality of nonlinear pulse patterns from a single linear pulse pattern. A first counter counts the pulses of the linear pulse pattern and a second counter counts the pulses of the nonlinear pulse pattern. A comparator compares the counts of both counters, and in response to an equal count, a gate is enabled to gate a pulse of the linear pattern as a pulse of the nonlinear pattern, the latter also resetting the first counter. Presettable dividers divide the pulses of each pattern before they are counted by the respective counters. Also, apparatus for generating a logarithmic pulse pattern from a linear pulse pattern to any log base. In one embodiment, a shift register is used in place of the second counter to be clocked by each pulse of the logarithmic pattern to generate the pattern. In another embodiment, a memory stores the logarithmic pattern and is addressed by the second counter which is clocked by the pulses of the logarithmic pulse pattern.

Nakamura, Michiyuki (Pleasant Hill, CA)

1981-01-01

27

Mining Frequent Patterns without Candidate Generation: A Frequent-Pattern Tree Approach  

Microsoft Academic Search

Mining frequent patterns in transaction databases, time-series databases, and many other kinds of databases has been studied popularly in data mining research. Most of the previous studies adopt an Apriori-like candidate set generation-and-test approach. However, candidate set generation is still costly, especially when there exist a large number of patterns and\\/or long patterns. In this study, we propose a novel

Jiawei Han; Jian Pei; Yiwen Yin; Runying Mao

2004-01-01

28

Synthesis of lithography test patterns through topology-oriented pattern extraction and classification  

NASA Astrophysics Data System (ADS)

Comprehensive and compact test patterns are crucial to the development of new semiconductor technology. In particular, the random nature of routing layers tends to create many hotspots, corresponding to patterns which are difficult to predict. Conventional group of test patterns consists of parametric typical patterns and real layout clips, which contain a lot of redundancy. The paper addresses a problem of generating comprehensive yet compact group of test patterns for random routing layers. A new method of pattern extraction and classification is proposed to solve the problem.

Shim, Seongbo; Chung, Woohyun; Shin, Youngsoo

2014-03-01

29

System Generating Competence Patterns of Organizational Groups  

Microsoft Academic Search

In recent years, knowledge management systems (KM- systems) for handling organizational knowledge have been the subject of sizeable interest within the research fields of CSCW and IS. However, information technology (IT) for managing competence has been debated less extensively. This paper describes and evaluates the design of Competence Visualizer (CV), which is a KM-system generating competence patterns of organizationa l

Rikard Lindgren

30

New downhole steam generator tested  

Microsoft Academic Search

Completion of 2 field tests of a new-model down-hole steam generator paves the way for further evaluation and development of a system destined to increase California's heavy oil production. Current air pollution restrictions there prevent installation of conventional steam generators in several areas of interest to oil operators. The current series of tests, conducted by Chemical Oil Recovery Co. (CORCO)

Bleakley

1981-01-01

31

Combinatorial Generation of Test Suites  

NASA Technical Reports Server (NTRS)

Testgen is a computer program that generates suites of input and configuration vectors for testing other software or software/hardware systems. As systems become ever more complex, often, there is not enough time to test systems against all possible combinations of inputs and configurations, so test engineers need to be selective in formulating test plans. Testgen helps to satisfy this need: In response to a test-suite-requirement-specification model, it generates a minimal set of test vectors that satisfies all the requirements.

Dvorak, Daniel L.; Barrett, Anthony C.

2009-01-01

32

Automated Test Generation with SAL  

Microsoft Academic Search

Abstract We describe sal-atg, a tool for automated test generation that will be distributed as part of the next release of SAL. Given a SAL specification augmented,with Boolean trap variables representing test goals, sal-atg generates an efficient set of tests to drive the trap variables to TRUE; SAL specifications are typically instrumented with trap variables representing structural coverage criteria during

Leonardo de Moura; John Rushby

2005-01-01

33

Implicit test generation for behavioral VHDL models  

Microsoft Academic Search

This paper proposes a behavioral-level test patterngeneration algorithm for behavioral VHDL descriptions.The proposed approach is based on the comparison betweenthe implicit description of the fault-free behaviorand the faulty behavior, obtained through a new behavioralfault model. The paper will experimentally showthat the test patterns generated at the behavioral levelprovide a very high stuck-at fault coverage when appliedto different gate-level implementations of

Fabrizio Ferrandi; Franco Fummi; Donatella Sciuto

1998-01-01

34

Data Generation for Path Testing  

Microsoft Academic Search

We present two stochastic search algorithms for generating test cases that execute specified paths in a program. The two algorithms are: a simulated annealing algorithm (SA), and a genetic algorithm (GA). These algorithms are based on an optimization formulation of the path testing problem which include both integer- and real-value test cases. We empirically compare the SA and GA algorithms

Nashat Mansour; Miran Salame

2004-01-01

35

ROLE OF INHIBITION IN RESPIRATORY PATTERN GENERATION  

PubMed Central

Postsynaptic inhibition is a key element of neural circuits underlying behavior, with 20-50% of all mammalian (non-granule) neurons considered inhibitory. For rhythmic movements in mammals, e.g., walking, swimming, suckling, chewing, breathing, inhibition is often hypothesized to play an essential rhythmogenic role. Here we study the role of fast synaptic inhibitory neurotransmission in the generation of breathing pattern by blocking GABAA and glycine receptors in the preBötzinger Complex (preBötC), a site essential for generation of normal breathing pattern, and in the neighboring Bötzinger Complex (BötC). The breathing rhythm continued following this blockade, but the lung inflation-induced Breuer-Hering inspiratory-inhibitory reflex was suppressed. The antagonists were efficacious, as this blockade abolished the profound effects of the exogenously applied GABAA receptor agonist muscimol or glycine, either of which under control conditions stopped breathing in vagus-intact or vagotomized, anesthetized, spontaneously breathing adult rats. In vagotomized rats, GABAAergic and glycinergic antagonists had little, if any, effect on rhythm. The effect in vagus intact rats was to slow the rhythm to a pace equivalent to that seen after suppression of the aforementioned Breuer-Hering inflation reflex. We conclude that postsynaptic inhibition within the preBötC and BötC is not essential for generation of normal respiratory rhythm in intact mammals. We suggest the primary role of inhibition is in shaping the pattern of respiratory motor output, assuring its stability, and in mediating reflex or volitional apnea, but not in the generation of rhythm per se.

Janczewski, Wiktor A.; Tashima, Alexis; Hsu, Paul; Cui, Yan; Feldman, Jack L.

2013-01-01

36

Test Generator for MATLAB Simulations  

NASA Technical Reports Server (NTRS)

MATLAB Automated Test Tool, version 3.0 (MATT 3.0) is a software package that provides automated tools that reduce the time needed for extensive testing of simulation models that have been constructed in the MATLAB programming language by use of the Simulink and Real-Time Workshop programs. MATT 3.0 runs on top of the MATLAB engine application-program interface to communicate with the Simulink engine. MATT 3.0 automatically generates source code from the models, generates custom input data for testing both the models and the source code, and generates graphs and other presentations that facilitate comparison of the outputs of the models and the source code for the same input data. Context-sensitive and fully searchable help is provided in HyperText Markup Language (HTML) format.

Henry, Joel

2011-01-01

37

New downhole steam generator tested  

SciTech Connect

Completion of 2 field tests of a new-model down-hole steam generator paves the way for further evaluation and development of a system destined to increase California's heavy oil production. Current air pollution restrictions there prevent installation of conventional steam generators in several areas of interest to oil operators. The current series of tests, conducted by Chemical Oil Recovery Co. (CORCO) of Bakersfield, California, follows an earlier prototype operation conducted by Sandia National Laboratories in conjunction with the US Department of Energy. The CORCO tests were conducted on the surface with the generator's output going into Tenneco Oil Exploration and Production Co.'s overland-Riokern Well No. 80, located in the Kern River field 4 miles north of Bakersfield. The first test was concluded with just under 1000 bbl of steam injected, less than planned due to a higher-than-expected injection pressure. The unit operated at less than 25% capacity because of the air compressor limitation. Compressor output was only 285 psi, not enough to inject the desired volumes into the reservoir. Test data shows that injection amounted to 150 bpd of 90 to 95% quality steam at 225-psi wellhead pressure. After injection, the well was shut in for 3 days to allow soaking, then put on production. Initial production was 40 bopd at 175 F.

Bleakley, W.B.

1981-07-01

38

Specification Test Coverage Adequacy Criteria = Specification Test Generation Inadequacy Criteria?  

Microsoft Academic Search

The successful analysis technique model checking can be employed as a test-case generation technique to generate tests from formal models. When using a model checker for test case generation, we leverage the witness (or counter- example) generation capability of model-checkers for con- structing test cases. Test criteria are expressed as temporal properties and the witness traces generated for these prop-

Mats Per Erik Heimdahl; George Devaraj; Robert Weber

2004-01-01

39

Testing Whether and When Abstract Symmetric Patterns Produce Affective Responses  

PubMed Central

Symmetry has a central role in visual art, it is often linked to beauty, and observers can detect it efficiently in the lab. We studied what kind of fast and automatic responses are generated by visual presentation of symmetrical patterns. Specifically, we tested whether a brief presentation of novel symmetrical patterns engenders positive affect using a priming paradigm. The abstract patterns were used as primes in a pattern-word interference task. To ensure that familiarity was not a factor, no pattern and no word was ever repeated within each experiment. The task was to classify words that were selected to have either positive or negative valence. We tested irregular patterns, patterns containing vertical and horizontal reflectional symmetry, and patterns containing a 90 deg rotation. In a series of 7 experiments we found that the effect of affective congruence was present for both types of regularity but only when observers had to classify the regularity of the pattern after responding to the word. The findings show that processing abstract symmetrical shapes or random pattern can engender positive or negative affect as long as the regularity of the pattern is a feature that observers have to attend to and classify.

Bertamini, Marco; Makin, Alexis; Pecchinenda, Anna

2013-01-01

40

Online Walking Pattern Generation for Biped Humanoid Robot with Trunk  

Microsoft Academic Search

This paper describes an online method generating walking patterns for biped humanoid robots having a trunk. Depending on the walking command, the motion patterns of the lower-limbs are created and connected to the prewalking patterns smoothly in online. For the stability of the biped robots, the trunk and the waist motion is generated by a walking stabilization control that is

Hun-ok Lim; Yoshiharu Kaneshimat; Atsuo Takanishi

2002-01-01

41

Examining the role of throughfall patterns on subsurface stormflow generation  

NASA Astrophysics Data System (ADS)

SummaryThe effect of throughfall input patterns on the hydrological response of forested hillslopes is not well understood. While field studies have contributed to our understanding of subsurface stormflow generation at the hillslope scale, such work is still of limited value because of the small number of places and events that have been characterized to date and the uniqueness of each study hillslope. In recent years, virtual experiments have been used to investigate the role of topography, soil depth, bedrock permeability and storm size, on the generation of lateral subsurface flow. However, these studies have generally assumed spatially uniform rainfall, and the interaction between vegetation and its effect on the spatial structure of input (canopy interception, throughfall) for hillslope hydrologic response has not yet been explored. Here we present a number of virtual experiments that explore the interplay among hydrological inputs (temporal and spatial distribution of rainfall) and hillslope properties (subsurface topography, soil depth), i.e. physical phenomena that are sources of space and/or time variability. We address specifically the relative importance of fine-scale throughfall patterns for hillslope hydrologic response. Topography and hydrologic field observations from an existing study hillslope were used to calibrate and test a 3D Richards equation-based finite element model. Throughfall patterns were based on published throughfall patterns in an even age stand of young conifers in the Pacific Northwest. These patterns were then varied across the hillslope during the virtual experiments. Our results showed that, surprisingly, the effect of spatial input variability of throughfall on lateral subsurface stormflow generation was minimal. For our tested case, the bedrock topography control on flow generation was much greater than the fine-scale spatial variability of the input. Using a spatially uniform area-averaged "throughfall" (i.e. open rainfall reduced by some assumed fraction, which is the simplest and most common form of throughfall representations) yielded minimal differences in subsurface stormflow response. Nevertheless, using open rainfall as spatially uniform input strongly overestimated lateral subsurface stormflow, and thus, the average impact of throughfall is important for input estimation at the hillslope-scale. Overall, the effects of fine-scale throughfall patterns on subsurface stormflow generation appear to be of secondary importance compared to effects of temporal distribution of rainfall, subsurface topography and variable soil depths.

Hopp, L.; McDonnell, J. J.

2011-10-01

42

Test Generator Program Features That Facilitate Classroom Testing.  

ERIC Educational Resources Information Center

Reviews seven commercially produced test generator programs appropriate for use by classroom teachers or individual instructors and identifies item construction and test formatting features that facilitate test design and delivery. Test generator programs and their manufacturers are listed. (MBR)

Brodeur, Doris R.

1986-01-01

43

Generation Pattern Search for Different Kinds of Economic Load Dispatch  

Microsoft Academic Search

The binary successive approximation (BSA) based evolutionary search strategy has been proposed to solve economic load dispatch (ELD) problem by searching the generation pattern of committed units. Inequality constraints are taken care during search of generation pattern. To meet the demand, a slack generator is introduced to compensate the perturbation of unmet load during the search. Performance of the algorithm

Jarnail S. Dhillon; D. P. Kothari

2007-01-01

44

Generation 1.5 Written Error Patterns: A Comparative Study  

ERIC Educational Resources Information Center

In an attempt to contribute to existing research on Generation 1.5 students, the current study uses quantitative and qualitative methods to compare error patterns in a corpus of Generation 1.5, L1, and L2 community college student writing. This error analysis provides one important way to determine if error patterns in Generation 1.5 student…

Doolan, Stephen M.; Miller, Donald

2012-01-01

45

Assertion-oriented automated test data generation  

Microsoft Academic Search

Assertions are recognized as a powerful tool for automatic run time detection of software errors. However, existing testing methods do not use assertions to generate test cases. We present a novel approach of automated test data generation in which assertions are used to generate test cases. In this approach the goal is to identify test cases on which an assertion

Bogdan Korel; Ali M. Al-Yami

1996-01-01

46

Research on Automatic Generation of Test Cases  

Microsoft Academic Search

Automatic generation of test cases is an integral part of the software automation testing system. This paper has designed a test case auto-generation model, this model can generate test cases based on knowledge such as rules, case studies, etc. Finally, this paper even conducts a discussion on the test case adequacy by the application of decision table.

Gao Gongge; Zhu Hao; Yang Jing

2012-01-01

47

Generation of the patterns in gaseous detonations  

Microsoft Academic Search

The problem addressed here is the mode of formation of the first initial regular pattern and its spacing in a detonation front. It is generally accepted that these patterns derive from a self-sustaining process of formation of Mach stems by colliding blast waves and blast waves from secondary local explosions initiated by these Mach stems. The reason for the very

F. Schultz-Grunow

1982-01-01

48

Generation of the Patterns in Gaseous Detonations.  

National Technical Information Service (NTIS)

The problem is the mode of formation of the first initial regular pattern and its spacing in a detonation front. It is generally accepted that these patterns are due to a selfsustaining process of formation of Mach stems by colliding blast waves by second...

F. Schultz-Grunow

1981-01-01

49

Vapor-Generator Wand Helps To Reveal Airflow Patterns  

NASA Technical Reports Server (NTRS)

In vapor-generator wand, liquid propylene glycol flows into electrically heated stainless-steel tube. Liquid boils in heated tube, and emerging vapor forms dense, smoke-like fog used to make airflow patterns visible. Built in variety of sizes, suitable for uses ranging from tabletop demonstrations to research in wind tunnels. For best viewing, plume illuminated by bright, focused incandescent spotlight at right angle to viewing direction. Viewing further enhanced by coating walls of test chamber with flat, dark color to minimize reflections and increase contrast.

Robelen, David B.

1993-01-01

50

Pattern analysis of photopatch test reactions.  

PubMed

In a multicenter study, photopatch test results from more than 1500 patients were evaluated between 1985 and 1990 and from 614 patients between 1990 and 1992. Photopatch testing was conducted according to a standardized procedure. Nearly half of the photoreactions were unclassifiable according to the classic definitions of photoallergic or phototoxic reactions. To facilitate the interpretation of these remaining photopatch test reactions, we developed a computerized substance specific reaction pattern analysis. By sequential readings from immediately after irradiation up to 72 h later and by morphological qualification of the reactions, the time course and morphological changes of each individual reaction were monitored. The summation of each individual photoreaction resulted in an overall reaction pattern of a specific substance. Four main categories could be distinguished. The first category was characterized by a peak immediately after irradiation followed by a descrescendo reaction. The second category comprized reactions combining an immediate with a delayed reaction. The third category exhibited a plateau-like delayed reaction. The fourth category showed delayed reactions in a crescendo pattern. Whereas category 1 represents classic phototoxic and category 4 classic photoallergic reaction patterns, the underlying mechanisms of categories 2 and 3 remain to be investigated. Typical substances of category 1 were many of the tested systemic drugs, such as furosemide, most of which are well-known phototoxic agents. Disinfectants, nonsteroidal anti-inflammatory agents and phenothiazines showed the reaction patterns of categories 2 and 3. A delayed type reaction (category 4) could be demonstrated for well-known photoallergens such as fenticlor, musk ambrette, and ultraviolet adsorbents in sunscreens.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8043387

Neumann, N J; Hölzle, E; Lehmann, P; Benedikter, S; Tapernoux, B; Plewig, G

1994-04-01

51

NEAT Drummer: Interactive Evolutionary Computation for Drum Pattern Generation  

Microsoft Academic Search

A major challenge in computer generated music is breaking the barrier between musical novelty and musical quality. Typically, computer music generators produce either genre-specific patterns that lack innovation or patterns that are given too much freedom and lack cohesion. In an attempt to both constrain the musical search space and produce novel rhythms, a program called NEAT Drummer is introduced.

Amy Kathryn Hoover; Kenneth O. Stanley

2007-01-01

52

Generation of the patterns in gaseous detonations  

NASA Astrophysics Data System (ADS)

The problem addressed here is the mode of formation of the first initial regular pattern and its spacing in a detonation front. It is generally accepted that these patterns derive from a self-sustaining process of formation of Mach stems by colliding blast waves and blast waves from secondary local explosions initiated by these Mach stems. The reason for the very first explosions and their spacing, however, are not known. It is shown here that this is caused by temperature perturbations as they are introduced with any kind of ignition. A steady mode of perturbation is derived which initiates the first local explosions at the extreme end of the combustion zone. They are substitutes for what is considered unrealistic asymptotic decrease. The concept is shown to be in agreement with measurements of the reaction time and of the spacing of soot patterns.

Schultz-Grunow, F.

53

A Survey on Automatic Test Data Generation  

Microsoft Academic Search

In order to reduce the high cost of manual software testing and at the same time to increase the reliabil- ity of the testing processes researchers and practition- ers have tried to automate it. One of the most impor- tant components in a testing environment is an auto- matic test data generator | a system that automati- cally generates test

Jon Edvardsson

1999-01-01

54

Traveling-Stripe Forcing Generates Hexagonal Patterns  

NASA Astrophysics Data System (ADS)

We study the response of Turing stripe patterns to a simple spatiotemporal forcing. This forcing has the form of a traveling wave and is spatially resonant with the characteristic Turing wavelength. Experiments conducted with the photosensitive chlorine dioxide-iodine-malonic acid reaction reveal a striking symmetry-breaking phenomenon of the intrinsic striped patterns giving rise to hexagonal lattices for intermediate values of the forcing velocity. The phenomenon is understood in the framework of the corresponding amplitude equations, which unveils a complex scenario of dynamical behaviors.

Míguez, D. G.; Nicola, E. M.; Muñuzuri, A. P.; Casademunt, J.; Sagués, F.; Kramer, L.

2004-07-01

55

On Test Generation through Programming in UDITA  

Microsoft Academic Search

\\u000aWe present an approach for describing tests using non-deterministic test generation programs. To write test generation programs, we introduce UDITA, a Java-based language with non-deterministic choice operators and an interface for generating linked structures. We also describe new algorithms that generate concrete tests by efficiently exploring the space of all executions of non-deterministic UDITA programs. We implemented our approach and

Milos Gligoric; Tihomir Gvero; Vilas Jagannath; Sarfraz Khurshid; Viktor Kuncak; Darko Marinov

2009-01-01

56

Generator acceptance test and inspection report  

SciTech Connect

This Acceptance Test Report(ATR) is the completed testing and inspection of the new portable generator. The testing and inspection is to verify that the generator provided by the vendor meets the requirements of specification WHC-S-0252, Revision 2. Attached is various other documentation to support the inspection and testing.

Johns, B.R.

1997-07-24

57

Compositional Dynamic Test Generation (Extended Abstract)  

Microsoft Academic Search

Dynamic test generation is a form of dynamic program analysis that attempts to compute test inputs to drive a program along a specific program path. Directed Automated Random Testing, or DART for short, blends dynamic test generation with model checking techniques with the goal of systematically executing all feasible program paths of a program while detecting various types of errors

Patrice Godefroid

58

Temperature Distortion Generator for Turboshaft Engine Testing.  

National Technical Information Service (NTIS)

The procedures and unique hardware used to conduct an experimental investigation into the response of a small-turboshaft-engine compression system to various hot gas ingestion patterns are presented. The temperature distortion generator described herein u...

G. A. Klann R. L. Barth T. J. Biesiadny

1984-01-01

59

Error-budget paradigms and laser mask pattern generator evolution  

NASA Astrophysics Data System (ADS)

The evolution of the ALTA(R) series of laser mask pattern generators has increased the relative contribution of intensity errors on critical-dimension (CD) control to those from placement errors. This paradigm shift has driven a change in rasterization strategy wherein aerial image sharpness is improved at the cost of a slight decrease in the averaging of column-to-column placement errors. Print performance evaluation using small-area CD test patterns show improvements in stripe-axis local CD uniformity (CDU) 3? values of 15-25% using the new strategy, and systematic brush-error contributions were reduced by 50%. The increased importance of intensity errors, coupled with the improvement of ALTA system performance, has also made the mask-blank and process-induced errors a more significant part of the overall error budget. A simple model based on two components, a pattern-invariant footprint and one related to the exposure density ?(x, y), is shown to describe adequately the errors induced by these sources. The first component is modeled by a fourth-order, two-dimensional polynomial, whereas the second is modeled as a convolution of ?(x, y) with one or more Gaussian kernels. Implementation of this model on the ALTA 4700 system shows improvements in global CDU of 50%.

Hamaker, H. Christopher; Jolley, Matthew J.; Berwick, Andrew D.

2009-01-01

60

Compact Marx generator test system  

Microsoft Academic Search

Marx generators have been built with a wide span of physical size and output capability, ranging from circuit board scale devices of a few stages up to systems capable of producing many Megavolts and occupying entire buildings. Our focus in this paper is the development of a capability to explore compact Marx generator (CMG) devices, where we arbitrarily define a

F. E. Peterkin; B. J. Hankla; J. L. Stevens; J. F. Sharrow; D. C. Stoudt

2002-01-01

61

Hierarchical test generation for VHDL behavioral models  

Microsoft Academic Search

In this method, the VHDL model to be tested is represented by its process model graph (PMG). Test sets for individual processes of the model are precomputed and stored in the design library. The Hierarchical Behavioral Test Generator (HBTG) algorithm accepts the PMG and the precomputed tests as inputs, from which it hierarchically constructs a test sequence that tests the

Sanat R. Rao; Bi-Yu Pan; James R. Armstrong

1993-01-01

62

Behaviour Directed Testing of Autocode Generators  

Microsoft Academic Search

This paper addresses the problem of testing auto-code generators. Auto-code generators take as input a model in certain modeling language, and produce as output a program that captures the execution semantics of the input-model. We focus on the problem of test specification for the purpose of automatically generating a test-suite. We propose a novel technique for test specification based on

Prahladavaradan Sampath; A. C. Rajeev; S. Ramesh; K. C. Shashidhar

2008-01-01

63

Generative models versus underlying symmetries to explain biological pattern.  

PubMed

Mathematical models play an increasingly important role in the interpretation of biological experiments. Studies often present a model that generates the observations, connecting hypothesized process to an observed pattern. Such generative models confirm the plausibility of an explanation and make testable hypotheses for further experiments. However, studies rarely consider the broad family of alternative models that match the same observed pattern. The symmetries that define the broad class of matching models are in fact the only aspects of information truly revealed by observed pattern. Commonly observed patterns derive from simple underlying symmetries. This article illustrates the problem by showing the symmetry associated with the observed rate of increase in fitness in a constant environment. That underlying symmetry reveals how each particular generative model defines a single example within the broad class of matching models. Further progress on the relation between pattern and process requires deeper consideration of the underlying symmetries. PMID:24750332

Frank, S A

2014-06-01

64

Item Generation for Test Development [Book Review].  

ERIC Educational Resources Information Center

This volume, based on papers presented at a 1998 conference, collects thinking and research on item generation for test development. It includes materials on psychometric and cognitive theory, construct-oriented approaches to item generation, the item generation process, and some applications of item generative principles. (SLD)

Papanastasiou, Elena C.

2003-01-01

65

Multithreaded Java program test generation  

Microsoft Academic Search

We describe ConTest, a tool for detecting synchronization faults in multithreaded Java, programs. The program under test is seeded with a sleep?, yield?, or priority? primitive at shared memory accesses and synchronization events. At run time, ConTest makes random or coverage-based decisions as to whether the seeded primitive is to be executed. Thus, the probability of finding concurrent faults is

Orit Edelstein; Eitan Farchi; Yarden Nir; Gil Ratsaby; Shmuel Ur

2001-01-01

66

Optimal On-Line Walking Pattern Generation for Biped Robots  

Microsoft Academic Search

A new 2D walking pattern generation method is proposed for biped robots in this paper. The key feature of the proposed method is to obtain an optimal walking pattern on-line with the largest stability in the sense of zero moment point (ZMP) subject to the constraints of torque and velocity of the joint actuators. With the aids of a 3-link

Hao Chen; Shuwen Pan; Rong Xiong; Jun Wu

2010-01-01

67

Generating Unit Tests from Formal Proofs  

Microsoft Academic Search

We present a new automatic test generation method for JAVA CARD based on attempts at formal verification of the implementati on under test (IUT). Self-contained unit tests in JUnit format are generated aut omatically. The advan- tages of the approach are: (i) it exploits the full informati on available in the IUT and in its formal model giving very good

Christian Engel; Reiner Hähnle

2007-01-01

68

Next Generation Automatic Test System (NGATS) Update  

Microsoft Academic Search

The next generation automatic test system (NGATS) is the latest addition to the Integrated family of test equipment (IFTE) developed and managed by product manager, test, measurement and diagnostic equipment (PM TMDE). This is Version 6 of what is commonly known as the Base Shop Test Facility series of systems developed by the off platform, automatic test system program. NGATS

P. A. Curry; J. Burden; G. A. Lundy

2006-01-01

69

Automated generation of SPICE characterization test masks and test databases  

Microsoft Academic Search

This paper presents procedures and software tools for automatic generation of test masks, and mask and measurement databases, for SPICE model characterization. The process uses Cadence Pcells, and requires user specification only of a small amount of biasing information. The tools generate device instances, place and route the devices, extract test array coordinates and contents from layout for auto-probing, generate

L. Kasel; C. C. McAndrew; P. Drennan; W. F. Davis; R. Ida

1999-01-01

70

Characteristic flow patterns generated by macrozoobenthic structures  

NASA Astrophysics Data System (ADS)

A laboratory flume channel, equipped with an acoustic Doppler flow sensor and a bottom scanning laser, was used for detailed, non-intrusive flow measurements (at 2 cm s - 1 and 10 cm s - 1 ) around solitary biogenic structures, combined with high-resolution mapping of the structure shape and position. The structures were replicates of typical macrozoobenthic species commonly found in the Mecklenburg Bight and with a presumed influence on both, the near-bed current regime and sediment transport dynamics: a worm tube, a snail shell, a mussel, a sand mound, a pit, and a cross-stream track furrow. The flow was considerably altered locally by the different protruding structures (worm tube, snail, mussel and mound). They reduced the horizontal approach velocity by 72% to 79% in the wake zone at about 1-2 cm height, and the flow was deflected around the structures with vertical and lateral velocities of up to 10% and 20% of the free-stream velocity respectively in a region adjacent to the structures. The resulting flow separation (at flow Reynolds number of about 4000 and 20,000 respectively) divided an outer deflection region from an inner region with characteristic vortices and the wake region. All protruding structures showed this general pattern, but also produced individual characteristics. Conversely, the depressions (track and pit) only had a weak influence on the local boundary layer flow, combined with a considerable flow reduction within their cavities (between 29% and 53% of the free-stream velocity). A longitudinal vortex formed, below which a stagnant space was found. The average height affected by the structure-related mass flow rate deficit for the two velocities was 1.6 cm and 1.3 cm respectively (80% of height and 64%) for the protruding structures and 0.6 cm and 0.9 cm (90% and 127% of depth) for the depressions. Marine benthic soft-bottom macrozoobenthos species are expected to benefit from the flow modifications they induce, particularly in terms of food particle capture due to altered particle pathways and residence times, but also for the exchange of gases, solutes and spawn. The present results confirm previous studies on flow interaction effects of various biogenic structures, and they add a deeper level of detail for a better understanding of the fine-scale effects.

Friedrichs, M.; Graf, G.

2009-02-01

71

Generating-Tree Isomorphisms for Pattern-Avoiding Involutions  

Microsoft Academic Search

We show that for k ? 5 and the permutations ?\\u000a \\u000a k\\u000a = (k ? 1)k(k ? 2). . .312 and J\\u000a \\u000a k\\u000a = k(k ? 1). . .21, the generating tree for involutions avoiding the pattern ?\\u000a \\u000a k\\u000a is isomorphic to the generating tree for involutions avoiding the pattern J\\u000a \\u000a k\\u000a . This implies a family of Wilf equivalences for pattern avoidance

Aaron D. Jaggard; Joseph J. Marincel

72

F-1 Engine Gas Generator Testing  

NASA Video Gallery

The gas generator from an F-1 engine is test-fired at the Marshall Space Flight Center in Huntsville, Ala., on Jan. 24, 2013. Data from the 30 second test will be used in the development of advance...

73

The BRH Test Pattern for Gamma Camera Performance (An Evaluator).  

National Technical Information Service (NTIS)

The present invention relates to evaluation of the performance of nuclear medicine imaging systems and, more particularly, to a transmission test pattern which can be utilized to determine the performance parameters of gamma cameras. The test pattern or p...

P. Paras

1981-01-01

74

Combining test case generation and runtime verification  

Microsoft Academic Search

Software testing is typically an ad-hoc process where human testers manually write test inputs and descriptions of expected test results, perhaps automating their execution in a regression suite. This process is cumbersome and costly. This paper reports results on a framework to further automate this process. The framework consists of combining auto- mated test case generation based on systematically exploring

Cyrille Artho; Howard Barringer; Allen Goldberg; Klaus Havelund; Sarfraz Khurshid; Michael R. Lowry; Corina S. Pasareanu; Grigore Rosu; Koushik Sen; Willem Visser; Richard Washington

2005-01-01

75

Neighborhood pattern-sensitive fault testing and diagnostics for random-access memories  

Microsoft Academic Search

The authors present test algorithms for go\\/no-go and diagnostic test of memories, covering neighborhood pattern-sensitive faults (NPSFs). The proposed test algorithms are March based, which have linear time complexity and result in a simple built-in self-test (BIST) implementation. Although conventional March algorithms do not generate all neighborhood patterns to test the NPSFs, they can be modified by using multiple data

Kuo-liang Cheng; Ming-fu Tsai; Cheng-wen Wu

2002-01-01

76

Nanoscale patterning of colloidal quantum dots for surface plasmon generation  

NASA Astrophysics Data System (ADS)

The patterning of colloidal quantum dots with nanometer resolution is essential for their application in photonics and plasmonics. Several patterning approaches, such as the use of polymer composites, molecular lock-and-key methods, inkjet printing, and microcontact printing of quantum dots, have limits in fabrication resolution, positioning and the variation of structural shapes. Herein, we present an adaptation of a conventional liftoff method for patterning colloidal quantum dots. This simple method is easy and requires no complicated processes. Using this method, we formed straight lines, rings, and dot patterns of colloidal quantum dots on metallic substrates. Notably, patterned lines approximately 10 nm wide were fabricated. The patterned structures display high resolution, accurate positioning, and well-defined sidewall profiles. To demonstrate the applicability of our method, we present a surface plasmon generator elaborated from quantum dots.

Park, Yeonsang; Roh, Young-Geun; Kim, Un Jeong; Chung, Dae-Young; Suh, Hwansoo; Kim, Jineun; Cheon, Sangmo; Lee, Jaesoong; Kim, Tae-Ho; Cho, Kyung-Sang; Lee, Chang-Won

2013-03-01

77

Generation of a Spacing Pattern: The Role of TRIPTYCHON in Trichome Patterning in Arabidopsis  

Microsoft Academic Search

Trichomes in Arabidopsis are single-celled hairs that exhibit a regular spacing pattern. Here, the role of TRIPTYCHON ( TRY ) in the generation of this spacing pattern is studied. By using genetic mosaics, we demonstrate that the formation of trichome clusters in try mutants is not correlated with cell lineage, indicating that TRY is required to single out tri- chome

Arp Schnittger; Ulrike Folkers; Birgit Schwab; Gerd Jürgens; Martin Hülskamp

1999-01-01

78

Delay test generation for synchronous sequential circuits  

NASA Astrophysics Data System (ADS)

We address the problem of generating tests for delay faults in non-scan synchronous sequential circuits. Delay test generation for sequential circuits is a considerably more difficult problem than delay testing of combinational circuits and has received much less attention. In this paper, we present a method for generating test sequences to detect delay faults in sequential circuits using the stuck-at fault sequential test generator STALLION. The method is complete in that it will generate a delay test sequence for a targeted fault given sufficient CPU time, if such a sequence exists. We term faults for which no delay test sequence exists, under out test methodology, sequentially delay redundant. We describe means of eliminating sequential delay redundancies in logic circuits. We present a partial-scan methodology for enhancing the testability of difficult-to-test of untestable sequential circuits, wherein a small number of flip-flops are selected and made controllable/observable. The selection process guarantees the elimination of all sequential delay redundancies. We show that an intimate relationship exists between state assignment and delay testability of a sequential machine. We describe a state assignment algorithm for the synthesis of sequential machines with maximal delay fault testability. Preliminary experimental results using the test generation, partial-scan and synthesis algorithm are presented.

Devadas, Srinivas

1989-05-01

79

Generating test programs to cover pipeline interactions  

Microsoft Academic Search

Functional validation of a processor design through execution of a suite of test programs is common industrial practice. In this paper, we develop a high-level architectural specification driven method- ology for systematic test-suite generation. Our primary contribu- tion is an automated test-suite generation methodology that covers all possible processor pipeline interactions. To accomplish this au- tomation, we (1) develop a

Thanh Nga Dang; Abhik Roychoudhury; Tulika Mitra; Prabhat Mishra

2009-01-01

80

Model-based pattern dummy generation for logic devices  

NASA Astrophysics Data System (ADS)

The insertion of SRAF(Sub-Resolution Assist Feature) is one of the most frequently used method to enlarge the process window area. In most cases, the size of SRAF is proportional to the focus margin of drawn patterns. However, there is a trade-off between the SRAF size and SRAF printing, because SRAF is not supposed to be patterned on a wafer. For this reason, a lot of OPC engineers have been tried to put bigger and more SRAFs within the limits of the possible. The fact that many papers about predicting SRAF printability have been published recent years reflects this circumstance. Pattern dummy is inserted to enhance the lithographic process margin and CD uniformity unlike CMP dummy for uniform metal line height. It is ordinary to put pattern dummy at the designated location under consideration of the pitch of real patterns at design step. However, it is not always desirable to generate pattern dummies based on rules at the lithographic point of view. In this paper, we introduce the model based pattern dummy insertion method, which is putting pattern dummies at the location that model based SRAF is located. We applied the model based pattern dummy to the layers in logic devices, and studied which layer is more efficient for the insertion of dummies.

Jang, Jongwon; Kim, Cheolkyun; Ko, Sungwoo; Byun, Seokyoung; Yang, Hyunjo; Yim, Donggyu

2014-03-01

81

Generating Test Templates via Automated Theorem Proving  

NASA Technical Reports Server (NTRS)

Testing can be used during the software development process to maintain fidelity between evolving specifications, program designs, and code implementations. We use a form of specification-based testing that employs the use of an automated theorem prover to generate test templates. A similar approach was developed using a model checker on state-intensive systems. This method applies to systems with functional rather than state-based behaviors. This approach allows for the use of incomplete specifications to aid in generation of tests for potential failure cases. We illustrate the technique on the cannonical triangle testing problem and discuss its use on analysis of a spacecraft scheduling system.

Kancherla, Mani Prasad

1997-01-01

82

Testing Software Product Lines Using Incremental Test Generation  

Microsoft Academic Search

We present a novel specification-based approach for generating tests for products in a software product line. Given properties of features as first-order logic formu- las, our approach uses SAT-based analysis to automat- ically generate test inputs for each product in a product line. To ensure soundness of generation, we introduce an automatic technique for mapping a formula that specifies a

Engin Uzuncaova; Daniel Garcia; Sarfraz Khurshid; Don S. Batory

2008-01-01

83

Automatic Generating Test Cases for Testing Web Applications  

Microsoft Academic Search

In order to ensure the security and reliability of Web application, the testing of Web application is one of the most effective methods. This work regards a Web application as the composition of different interactive logical components (LCs). We combine LCs with agent to assist to automatic generate test cases for testing Web applications. From pages-flow-diagram (PFD) of Web application

Shengbo Chen; Huaikou Miao; Zhongsheng Qian

2007-01-01

84

Capture-based Automated Test Input Generation  

Microsoft Academic Search

Testing object-oriented software is critical because object-oriented languages have been commonly used in developing modern software systems. Many efficient test input generation techniques for object-oriented software have been proposed; however, state-of-the-art algorithms yield very low code coverage (e.g., less than 50%) on large-scale software. Therefore, one important and yet challenging problem is to generate desirable input objects for receivers and

Hojun Jaygarl

2010-01-01

85

Pattern generation for bipedal walking on slopes and stairs  

Microsoft Academic Search

Uneven terrain walking is one of the key challenges in bipedal walking. In this paper, we propose a motion pattern generator for slope walking in 3D dynamics using preview control of zero moment point (ZMP). In this method, the future ZMP locations are selected with respect to known slope gradient. The trajectory of the center of mass (CoM) of the

Weiwei Huang; Chee-Meng Chew; Yu Zheng; Geok-Soon Hong

2008-01-01

86

Optimization based gait pattern generation for a biped robot  

Microsoft Academic Search

This paper addresses the problem of gait pattern generation for biped robots. A method based on nonlinear parameter optimization is proposed. Key features of the method are the trajectory description, optimization of only a subset of coordinates and the use of analytical, recursively calculated gradients for cost functions and constraints. The method has been used successfully to calculate walking trajectories

Thomas Buschmann; Sebastian Lohmeier; Heinz Ulbrich; Friedrich Pfeiffer

2005-01-01

87

Steam Generator Tube Denting Simulation Testing.  

National Technical Information Service (NTIS)

Tube denting has been reported in steam generators in a number of commercial nuclear power plants in recent years. In order to aid in understanding of the mechanism leading to tube denting in the steam generators, a Bettis laboratory test program was init...

P. J. Battaglia W. J. Singley

1978-01-01

88

Steam generator tube denting simulation testing. [PWR  

Microsoft Academic Search

Tube denting has been reported in steam generators in a number of commercial nuclear power plants in recent years. In order to aid in understanding of the mechanism leading to tube denting in the steam generators, a Bettis laboratory test program was initiated to attempt to reproduce tube denting and to investigate the effects of chemistry, design, and temperature. The

P. J. Battaglia; W. J. Singley

1978-01-01

89

A stochastic model for generating disturbance patterns within landscapes  

NASA Astrophysics Data System (ADS)

A stochastic model for generating disturbances in landscapes that interfaces with geographic information systems (GIS) is presented. The model operates on a lattice (rectangular array of points) using a space-time Markov process, which gives a stochastic simulation of growth patterns in terms of parameters of the local region. The model generates disturbance patterns on the landscape based on user-defined inputs of the total area disturbed and the number of patches to be disturbed. The model is developed in a C++ software package named "TDsimulator" ("Terrain Disturbance Simulator") which can be used to predict changes in landscape cover under a variety of stochastic scenarios. The software comprises a set of GIS routines that collectively yield the disturbance patterns. A demonstration of the stochastic model is provided for simulating fire behaviour in a forested landscape. The numerical examples illustrate the total disturbance impact under different initial conditions and scenarios.

Krougly, Z. L.; Creed, I. F.; Stanford, D. A.

2009-07-01

90

The thermoelectric generator test program at JPL.  

NASA Technical Reports Server (NTRS)

Discussion of the test results and analysis performed on data obtained from eight thermoelectric generators exhibiting a total combined operating time of about 21 years. Three (3) SNAP-19 type generators are discussed. Generator SN-20, the engineering model of the units presently operating on the Nimbus S/C, has been in operation for over 4 years and has shown drastic degradation after losing the internal cover gas. Generator SN-21, with more than four years of operating time, is operated in an air environment. The performance of this generator appears predictable and stable. For the last 2 years of operation generator degradation has been negligible. Generator SN-31, which utilizes the TAGS material for the P thermoelectric leg, is similar in design to the units to be used on the Pioneer S/C and has operated for over two years in an all-argon atmosphere.

Stapfer, G.; Rouklove, P.

1972-01-01

91

Test Generation through Programming in UDITA  

Microsoft Academic Search

\\u000aWe present an approach for describing tests using non-deterministic\\u000atest generation programs. To write such programs, we introduce UDITA,\\u000aa Java-based language with non-deterministic choice operators and an\\u000ainterface for generating linked structures. We also describe new\\u000aalgorithms that generate concrete tests by efficiently exploring the\\u000aspace of all executions of non-deterministic UDITA programs.\\u000a\\u000aWe implemented our approach and incorporated

Milos Gligoric; Tihomir Gvero; Vilas Jagannath; Sarfraz Khurshid; Viktor Kuncak; Darko Marinov

2010-01-01

92

MYSID TWO-GENERATION TEST GUIDELINE  

EPA Science Inventory

McKenney, Charles L., Jr. In press. Mysid Two-Generation Test Guideline. OECD Expert Group on Invertebrate Testing for Endocrine Disruptors, Organisation for Economic Co-operation and Development, Paris, France. 17 p. (ERL,GB 1215). This guideline describes a two-generati...

93

Alcohol LOX Steam Generator Test Experience  

NASA Astrophysics Data System (ADS)

At the DLR test centre in Lampoldshausen there is a long experience in the development of rocket steam generators as a main subsystem for the altitude simulation. The rocket steam generators make it possible to supply the required quantities of steam at short notice with reduced investment and operating costs. The rocket steam generators are based on the combustion of liquid oxygen (LOX) and ethyl alcohol (ALC). The paper deals with the experience of the development of the steam generators and the operation at the altitude simulation P1.0 for satellite propulsion and P4.2 for altitude simulation of AESTUS upper stage engine.

Schaefer, K.; Dommers, M.

2004-10-01

94

THE IDENTIFICATION AND TESTING OF INTERACTION PATTERNS  

EPA Science Inventory

This paper presents a method for identifying and assessing the significance of interaction patterns among various chemicals and chemical classes of importance to regulatory toxicologists. To this end, efforts were made to assemble and evaluate experimental data on toxicologically...

95

Formal methods for test case generation  

NASA Technical Reports Server (NTRS)

The invention relates to the use of model checkers to generate efficient test sets for hardware and software systems. The method provides for extending existing tests to reach new coverage targets; searching *to* some or all of the uncovered targets in parallel; searching in parallel *from* some or all of the states reached in previous tests; and slicing the model relative to the current set of coverage targets. The invention provides efficient test case generation and test set formation. Deep regions of the state space can be reached within allotted time and memory. The approach has been applied to use of the model checkers of SRI's SAL system and to model-based designs developed in Stateflow. Stateflow models achieving complete state and transition coverage in a single test case are reported.

Rushby, John (Inventor); De Moura, Leonardo Mendonga (Inventor); Hamon, Gregoire (Inventor)

2011-01-01

96

Diesel generator trailer acceptance test procedure  

SciTech Connect

This Acceptance Test Procedure (ATP) will document compliance with the requirements of WHC-S-0252 Rev. 1 and ECNs 609271, and 609272. The equipment being tested is a 150KW Diesel Generator mounted on a trailer with switchgear. The unit was purchased as a Design and Fabrication procurement activity. The ATP was written by the Seller and will be performed by the Seller with representatives of the Westinghouse Hanford Company witnessing the test at the Seller`s location.

Kostelnik, A.J.

1994-09-23

97

Fast hologram pattern generation by wave field translation  

NASA Astrophysics Data System (ADS)

In this paper, we present a fast hologram pattern generation method to overcome accumulation problem of point source based method. Proposed method consists of two steps. In the first step, 2D projection of wave field for 3D object is calculated by radial symmetric interpolation (RSI) method to the multiple reference depth planes. Then in the second step, each 2D wave field is translated toward SLM plane by FFT based algorithm. Final hologram pattern is obtained by adding them. The effectiveness of method is proved by computer simulation and optical experiment. Experimental results show that proposed method is 3878 times faster than analytic method, and 226 times faster than RSI method.

Lee, S.; Wey, H. C.; Nam, D. K.; Park, D. S.

2013-09-01

98

Order parameter for bursting polyrhythms in multifunctional central pattern generators  

NASA Astrophysics Data System (ADS)

We examine multistability of several coexisting bursting patterns in a central pattern generator network composed of three Hodgkin-Huxley type cells coupled reciprocally by inhibitory synapses. We establish that the control of switching between bursting polyrhythms and their bifurcations are determined by the temporal characteristics, such as the duty cycle, of networked interneurons and the coupling strength asymmetry. A computationally effective approach to the reduction of dynamics of the nine-dimensional network to two-dimensional Poincaré return mappings for phase lags between the interneurons is presented.

Wojcik, Jeremy; Clewley, Robert; Shilnikov, Andrey

2011-05-01

99

Swiss Cheese Test Case Generation for Web Services Testing  

Microsoft Academic Search

Current Web services testing techniques are unable to assure the desired level of trustworthiness, which presents a barrier to WS applications in mission and business critical environments. This paper presents a framework that assures the trustworthiness of Web services. New assurance techniques are developed within the framework, including specification verification via completeness and consistency checking, test case generation, and automated

Wei-Tek Tsai; Xiao Wei; Yinong Chen; Raymond A. Paul; Xiaoying Bai

2005-01-01

100

Override of spontaneous respiratory pattern generator reduces cardiovascular parasympathetic influence  

NASA Technical Reports Server (NTRS)

We investigated the effects of voluntary control of breathing on autonomic function in cardiovascular regulation. Variability in heart rate was compared between 5 min of spontaneous and controlled breathing. During controlled breathing, for 5 min, subjects voluntarily reproduced their own spontaneous breathing pattern (both rate and volume on a breath-by-breath basis). With the use of this experimental design, we could unmask the effects of voluntary override of the spontaneous respiratory pattern generator on autonomic function in cardiovascular regulation without the confounding effects of altered respiratory pattern. Results from 10 subjects showed that during voluntary control of breathing, mean values of heart rate and blood pressure increased, whereas fractal and spectral powers in heart rate in the respiratory frequency region decreased. End-tidal PCO2 was similar during spontaneous and controlled breathing. These results indicate that the act of voluntary control of breathing decreases the influence of the vagal component, which is the principal parasympathetic influence in cardiovascular regulation.

Patwardhan, A. R.; Vallurupalli, S.; Evans, J. M.; Bruce, E. N.; Knapp, C. F.

1995-01-01

101

Towards multifocal ultrasonic neural stimulation: pattern generation algorithms  

NASA Astrophysics Data System (ADS)

Focused ultrasound (FUS) waves directed onto neural structures have been shown to dynamically modulate neural activity and excitability, opening up a range of possible systems and applications where the non-invasiveness, safety, mm-range resolution and other characteristics of FUS are advantageous. As in other neuro-stimulation and modulation modalities, the highly distributed and parallel nature of neural systems and neural information processing call for the development of appropriately patterned stimulation strategies which could simultaneously address multiple sites in flexible patterns. Here, we study the generation of sparse multi-focal ultrasonic distributions using phase-only modulation in ultrasonic phased arrays. We analyse the relative performance of an existing algorithm for generating multifocal ultrasonic distributions and new algorithms that we adapt from the field of optical digital holography, and find that generally the weighted Gerchberg-Saxton algorithm leads to overall superior efficiency and uniformity in the focal spots, without significantly increasing the computational burden. By combining phased-array FUS and magnetic-resonance thermometry we experimentally demonstrate the simultaneous generation of tightly focused multifocal distributions in a tissue phantom, a first step towards patterned FUS neuro-modulation systems and devices.

Hertzberg, Yoni; Naor, Omer; Volovick, Alexander; Shoham, Shy

2010-10-01

102

Towards multifocal ultrasonic neural stimulation: pattern generation algorithms.  

PubMed

Focused ultrasound (FUS) waves directed onto neural structures have been shown to dynamically modulate neural activity and excitability, opening up a range of possible systems and applications where the non-invasiveness, safety, mm-range resolution and other characteristics of FUS are advantageous. As in other neuro-stimulation and modulation modalities, the highly distributed and parallel nature of neural systems and neural information processing call for the development of appropriately patterned stimulation strategies which could simultaneously address multiple sites in flexible patterns. Here, we study the generation of sparse multi-focal ultrasonic distributions using phase-only modulation in ultrasonic phased arrays. We analyse the relative performance of an existing algorithm for generating multifocal ultrasonic distributions and new algorithms that we adapt from the field of optical digital holography, and find that generally the weighted Gerchberg-Saxton algorithm leads to overall superior efficiency and uniformity in the focal spots, without significantly increasing the computational burden. By combining phased-array FUS and magnetic-resonance thermometry we experimentally demonstrate the simultaneous generation of tightly focused multifocal distributions in a tissue phantom, a first step towards patterned FUS neuro-modulation systems and devices. PMID:20720281

Hertzberg, Yoni; Naor, Omer; Volovick, Alexander; Shoham, Shy

2010-10-01

103

Improved methodology for generating controlled test atmospheres  

Microsoft Academic Search

Improved methodology has been developed for generating controlled test atmospheres. Vaporization of volatile liquids is accomplished in a 28?mm (O.D.) glass J-tube in conjunction with a compressed air flameless heat torch, a pressure-sensitive switch, and a positive displacement piston pump. The vaporization system has been very reliable with a variety of test materials in studies ranging from a few days

R. R. MILLER; R. L LETTS; W. J. POTTS; M. J. McKENNA

1980-01-01

104

Calibrating Droplet Generator for Pressurized Testing Vessel  

NASA Technical Reports Server (NTRS)

Device helps to aline laser for droplet-sizing interferometer. Monodispersing Droplet Generator creates uniformly sized droplets. Laser source and receiver of interferometer alined and focused on droplets. MDG mounted in high-pressure flange on tank. Line extensions pass through flange to outside. Flange allows MDG to operate at high injector back pressures used for tests.

Defever, G. J.; Exposito, T.

1985-01-01

105

Sequential Circuit Test Generator (STG) benchmark results  

Microsoft Academic Search

The authors report on the results of running a version of the Sequential Circuit Test Generator (STG3) on the ISCAS-89 sequential circuit benchmarks. First, they present a brief history of STG and briefly describe the algorithms used. They then describe the conditions under which the experiments were run and give the benchmark results. No particular problems were encountered when running

W.-T. Cheng; S. Davidson

1989-01-01

106

Multiple Distributions for Biased Random Test Patterns  

Microsoft Academic Search

In this paper, it is shown that the problem can be solved using sev- eral distributions instead of a single one. Furthermore, an efficient pro- cedure for computing the optimized input probabilities is presented. If a sufficient number of distributions is applied, then all combinational circuits can be tested randomly with moderate test lengths. The pat- terns can be produced

Hans-joachim Wunderlich; D. Schmid; F. R. Germany

1988-01-01

107

Improved methodology for generating controlled test atmospheres.  

PubMed

Improved methodology has been developed for generating controlled test atmospheres. Vaporization of volatile liquids is accomplished in a 28 mm (O.D.) glass J-tube in conjunction with a compressed air flameless heat torch, a pressure-sensitive switch, and a positive displacement piston pump. The vaporization system has been very reliable with a variety of test materials in studies ranging from a few days to several months. The J-tube vaporization assembly minimizes the possibility of thermal decomposition of the test material and affords a better margin of safety when vaporizing potentially explosive materials. PMID:7457377

Miller, R R; Letts, R L; Potts, W J; McKenna, M J

1980-11-01

108

Neuromodulation and flexibility in Central Pattern Generator networks.  

PubMed

Central Pattern Generator (CPG) networks, which organize rhythmic movements, have long served as models for neural network organization. Modulatory inputs are essential components of CPG function: neuromodulators set the parameters of CPG neurons and synapses to render the networks functional. Each modulator acts on the network by many effects which may oppose one another; this may serve to stabilize the modulated state. Neuromodulators also determine the active neuronal composition in the CPG, which varies with state changes such as locomotor speed. The pattern of gene expression which determines the electrophysiological personality of each CPG neuron is also under modulatory control. It is not possible to model the function of neural networks without including the actions of neuromodulators. PMID:21646013

Harris-Warrick, Ronald M

2011-10-01

109

The generation of vertebral segmental patterning in the chick embryo  

PubMed Central

We have carried out a series of experimental manipulations in the chick embryo to assess whether the notochord, neural tube and spinal nerves influence segmental patterning of the vertebral column. Using Pax1 expression in the somite-derived sclerotomes as a marker for segmentation of the developing intervertebral disc, our results exclude such an influence. In contrast to certain teleost species, where the notochord has been shown to generate segmentation of the vertebral bodies (chordacentra), these experiments indicate that segmental patterning of the avian vertebral column arises autonomously in the somite mesoderm. We suggest that in amniotes, the subdivision of each sclerotome into non-miscible anterior and posterior halves plays a critical role in establishing vertebral segmentation, and in maintaining left/right alignment of the developing vertebral elements at the body midline.

Senthinathan, Biruntha; Sousa, Catia; Tannahill, David; Keynes, Roger

2012-01-01

110

Generation of a spacing pattern: the role of triptychon in trichome patterning in Arabidopsis.  

PubMed Central

Trichomes in Arabidopsis are single-celled hairs that exhibit a regular spacing pattern. Here, the role of TRIPTYCHON (TRY) in the generation of this spacing pattern is studied. By using genetic mosaics, we demonstrate that the formation of trichome clusters in try mutants is not correlated with cell lineage, indicating that TRY is required to single out trichome cells in a process involving cellular interactions. The genetic interactions of TRY, GLABRA1 (GL1), and TRANSPARENT TESTA GLABRA (T TG) in trichome patterning are assessed by determining the cluster frequency in various genetic combinations. It is shown that TRY acts as a negative regulator of GL1- and TTG-dependent pathways. Furthermore, it is demonstrated that trichome initiation in ttg-1, a strong ttg allele, is rescued almost to wild-type levels in a try background in which GL1 is expressed under the control of the cauliflower mosaic virus 35S promoter, indicating that T TG acts upstream of GL1 and TRY. These findings are incorporated into a model to explain the generation of a trichome spacing pattern from a homogeneous population of epidermal cells.

Schnittger, A; Folkers, U; Schwab, B; Jurgens, G; Hulskamp, M

1999-01-01

111

Automated Test Data Generation for Programs with Procedures  

Microsoft Academic Search

Test data generation in program testing is the process of identifying a set of test data that satisfies a selected testing criterion, such as, statement coverage or branch coverage. The existing methods of test data generation are limited to unit testing and may not efficiently generate test data for programs with procedures. In this paper we present an approach for

Bogdan Korel

1996-01-01

112

A Hormone-Activated Central Pattern Generator For Courtship  

PubMed Central

Summary Background Medicinal leeches (Hirudo spp.) are simultaneous hermaphrodites. Mating occurs after a stereotyped twisting and oral exploration that result in the alignment of the male and/or female gonopores of one leech with the complementary gonopores of a partner. The neural basis of this behavior is presently unknown and currently impossible to study directly because electrophysiological recording techniques disrupt the behavior. Results Here we report that (Arg8)-conopressin G and two other members of the oxytocin/vasopressin family of peptide hormones induce in Hirudo verbana a sequence of behaviors that closely mimic elements of spontaneous reproductive behavior. Through a series of progressively more reduced preparations, we show that one of these behaviors, a stereotyped twisting that is instrumental to aligning gonopores in preparation for copulation, is the product of a central pattern generator that consists of oscillators in ganglia M5 and M6 (the ganglia in the reproductive segments of the leech), and also in ganglion M4, which was not previously known to play a role in reproductive behavior. We find that the behavior is periodic, with a remarkably long cycle period of around five minutes, placing it among the slowest behavioral rhythms (other than diurnal and annual rhythms) yet described. Conclusion These results establish the leech as a new model system for studying aspects of the neuronal basis of reproductive behavior. Highlights Oxytocin/vasopressin homologues induce pre-copulatory movements in a leech. These movements are generated by a central pattern generator. Segmental ganglia M4, M5, and M6 can each generate fictive behavior in isolation.

Hamilton, M. Sarhas; Huang, Tracy; Kristan, William B.; French, Kathleen A.

2010-01-01

113

Sequentially firing neurons confer flexible timing in neural pattern generators  

SciTech Connect

Neuronal networks exhibit a variety of complex spatiotemporal patterns that include sequential activity, synchrony, and wavelike dynamics. Inhibition is the primary means through which such patterns are implemented. This behavior is dependent on both the intrinsic dynamics of the individual neurons as well as the connectivity patterns. Many neural circuits consist of networks of smaller subcircuits (motifs) that are coupled together to form the larger system. In this paper, we consider a particularly simple motif, comprising purely inhibitory interactions, which generates sequential periodic dynamics. We first describe the dynamics of the single motif both for general balanced coupling (all cells receive the same number and strength of inputs) and then for a specific class of balanced networks: circulant systems. We couple these motifs together to form larger networks. We use the theory of weak coupling to derive phase models which, themselves, have a certain structure and symmetry. We show that this structure endows the coupled system with the ability to produce arbitrary timing relationships between symmetrically coupled motifs and that the phase relationships are robust over a wide range of frequencies. The theory is applicable to many other systems in biology and physics.

Urban, Alexander; Ermentrout, Bard [Department of Physics, University of Pittsburgh, 100 Allen Hall, 3941 O'Hara Street, Pittsburgh, Pennsylvania 15260 (United States); Department of Mathematics, University of Pittsburgh, 139 University Place, Pittsburgh, Pennsylvania 15260 (United States)

2011-05-15

114

Generation of arbitrary complex quasi-non-diffracting optical patterns.  

PubMed

Due to their unique ability to maintain an intensity distribution upon propagation, non-diffracting light fields are used extensively in various areas of science, including optical tweezers, nonlinear optics and quantum optics, in applications where complex transverse field distributions are required. However, the number and type of rigorously non-diffracting beams is severely limited because their symmetry is dictated by one of the coordinate system where the Helmholtz equation governing beam propagation is separable. Here, we demonstrate a powerful technique that allows the generation of a rich variety of quasi-non-diffracting optical beams featuring nearly arbitrary intensity distributions in the transverse plane. These can be readily engineered via modifications of the angular spectrum of the beam in order to meet the requirements of particular applications. Such beams are not rigorously non-diffracting but they maintain their shape over large distances, which may be tuned by varying the width of the angular spectrum. We report the generation of unique spiral patterns and patterns involving arbitrary combinations of truncated harmonic, Bessel, Mathieu, or parabolic beams occupying different spatial domains. Optical trapping experiments illustrate the opto-mechanical properties of such beams. PMID:24104114

Ortiz-Ambriz, Antonio; Lopez-Aguayo, Servando; Kartashov, Yaroslav V; Vysloukh, Victor A; Petrov, Dmitri; Garcia-Gracia, Hipolito; Gutiérrez-Vega, Julio C; Torner, Lluis

2013-09-23

115

Central pattern generator for locomotion: anatomical, physiological, and pathophysiological considerations.  

PubMed

This article provides a perspective on major innovations over the past century in research on the spinal cord and, specifically, on specialized spinal circuits involved in the control of rhythmic locomotor pattern generation and modulation. Pioneers such as Charles Sherrington and Thomas Graham Brown have conducted experiments in the early twentieth century that changed our views of the neural control of locomotion. Their seminal work supported subsequently by several decades of evidence has led to the conclusion that walking, flying, and swimming are largely controlled by a network of spinal neurons generally referred to as the central pattern generator (CPG) for locomotion. It has been subsequently demonstrated across all vertebrate species examined, from lampreys to humans, that this CPG is capable, under some conditions, to self-produce, even in absence of descending or peripheral inputs, basic rhythmic, and coordinated locomotor movements. Recent evidence suggests, in turn, that plasticity changes of some CPG elements may contribute to the development of specific pathophysiological conditions associated with impaired locomotion or spontaneous locomotor-like movements. This article constitutes a comprehensive review summarizing key findings on the CPG as well as on its potential role in Restless Leg Syndrome, Periodic Leg Movement, and Alternating Leg Muscle Activation. Special attention will be paid to the role of the CPG in a recently identified, and uniquely different neurological disorder, called the Uner Tan Syndrome. PMID:23403923

Guertin, Pierre A

2012-01-01

116

Central Pattern Generator for Locomotion: Anatomical, Physiological, and Pathophysiological Considerations  

PubMed Central

This article provides a perspective on major innovations over the past century in research on the spinal cord and, specifically, on specialized spinal circuits involved in the control of rhythmic locomotor pattern generation and modulation. Pioneers such as Charles Sherrington and Thomas Graham Brown have conducted experiments in the early twentieth century that changed our views of the neural control of locomotion. Their seminal work supported subsequently by several decades of evidence has led to the conclusion that walking, flying, and swimming are largely controlled by a network of spinal neurons generally referred to as the central pattern generator (CPG) for locomotion. It has been subsequently demonstrated across all vertebrate species examined, from lampreys to humans, that this CPG is capable, under some conditions, to self-produce, even in absence of descending or peripheral inputs, basic rhythmic, and coordinated locomotor movements. Recent evidence suggests, in turn, that plasticity changes of some CPG elements may contribute to the development of specific pathophysiological conditions associated with impaired locomotion or spontaneous locomotor-like movements. This article constitutes a comprehensive review summarizing key findings on the CPG as well as on its potential role in Restless Leg Syndrome, Periodic Leg Movement, and Alternating Leg Muscle Activation. Special attention will be paid to the role of the CPG in a recently identified, and uniquely different neurological disorder, called the Uner Tan Syndrome.

Guertin, Pierre A.

2013-01-01

117

21 CFR 892.1420 - Radionuclide test pattern phantom.  

Code of Federal Regulations, 2010 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1420 Radionuclide test pattern phantom. (a) Identification. A...

2010-04-01

118

21 CFR 892.1420 - Radionuclide test pattern phantom.  

Code of Federal Regulations, 2011 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1420 Radionuclide test pattern phantom. (a) Identification. A...

2011-04-01

119

21 CFR 892.1420 - Radionuclide test pattern phantom.  

Code of Federal Regulations, 2012 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1420 Radionuclide test pattern phantom. (a) Identification. A...

2012-04-01

120

21 CFR 892.1420 - Radionuclide test pattern phantom.  

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1420 Radionuclide test pattern phantom. (a) Identification. A...

2014-04-01

121

21 CFR 892.1420 - Radionuclide test pattern phantom.  

Code of Federal Regulations, 2013 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1420 Radionuclide test pattern phantom. (a) Identification. A...

2013-04-01

122

Detecting Response Bias with Performance Patterns on an Expanded Version of the Controlled Oral Word Association Test  

Microsoft Academic Search

The present study investigated whether speeded word generation performance patterns seen in healthy subjects are also produced in genuine and feigned traumatic brain injury (TBI). An expanded version of the Controlled Oral Word Association Test was administered to healthy controls, TBI patients, simulated malingerers, and probable clinical malingerers. Four performance patterns were operationalized. Three of these patterns were replicated in

Noah D. Silverberg; Robin A. Hanks; Lori Buchanan; Norm Fichtenberg; Scott R. Millis

2008-01-01

123

Generative, Descriptive, Heuristic, and Formal Modeling in Pattern Analysis and Classification.  

National Technical Information Service (NTIS)

Generative grammars and pattern descriptions have been recently associated primarily with the Linguistic School of pattern recognition research. The author shows that very similar types of generative and descriptive models are used extensively in obtainin...

L. N. Kanal

1971-01-01

124

49 CFR 229.114 - Steam generator inspections and tests.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Steam generator inspections and tests. 229.114 Section...SAFETY STANDARDS Safety Requirements Steam Generators § 229.114 Steam generator inspections and tests. (a) Periodic...

2013-10-01

125

Optimal Test Design with Rule-Based Item Generation  

ERIC Educational Resources Information Center

Optimal test-design methods are applied to rule-based item generation. Three different cases of automated test design are presented: (a) test assembly from a pool of pregenerated, calibrated items; (b) test generation on the fly from a pool of calibrated item families; and (c) test generation on the fly directly from calibrated features defining…

Geerlings, Hanneke; van der Linden, Wim J.; Glas, Cees A. W.

2013-01-01

126

Using the WWW Test Pattern to check HTML Client Compliance  

Microsoft Academic Search

The World Wide Web Test Pattern is a Web site that was conceived as a general-purpose test bench so that users and developers can check for HTML compliance. While still under construction, it already includes a standard suite of tests for text, audio, graphics, meta-links, animations, forms and tables. The URL is http:\\/\\/www.uark.edu\\/?wrg\\/. There is a tiled background to the

Hal Berghel

1995-01-01

127

Design for Testability and Test Generation for Static Redundancy System Level Fault-Tolerant Circuits  

Microsoft Academic Search

The necessary conditions for designing testable static redundancy system-level fault-tolerant circuits are derived. In addition, algorithms are proposed for the efficient generation of test patterns for fault-tolerant circuits designed to satisfy these testability conditions. The test generation algorithm has been incorporated with an algorithm for the construction of majority voting devices and automated to produce a software package that generates

Charles E. Stroud; Ahmed E. Barbour

1989-01-01

128

Validation Testing of Hydrogen Generation Technology  

SciTech Connect

This report describes the results of testing performed by ORNL for Photech Energies, Inc. The objective of the testing was to evaluate the efficacy of Photech's hydrogen generation reactor technology, which produces gaseous hydrogen through electrolysis. Photech provided several prototypes of their proprietary reactor for testing and the ancillary equipment, such as power supplies and electrolyte solutions, required for proper operation of the reactors. ORNL measured the production of hydrogen gas (volumetric flow of hydrogen at atmospheric pressure) as a function of input power and analyzed the composition of the output stream to determine the purity of the hydrogen content. ORNL attempted measurements on two basic versions of the prototype reactors-one version had a clear plastic outer cylinder, while another version had a stainless steel outer cylinder-but was only able to complete measurements on reactors in the plastic version. The problem observed in the stainless steel reactors was that in these reactors most of the hydrogen was produced near the anodes along with oxygen and the mixed gases made it impossible to determine the amount of hydrogen produced. In the plastic reactors the production of hydrogen gas increased monotonically with input power, and the flow rates increased faster at low input powers than they did at higher input powers. The maximum flow rate from the cathode port measured during the tests was 0.85 LPM at an input power of about 1100 W, an electrolyte concentration of 20%. The composition of the flow from the cathode port was primarily hydrogen and water vapor, with some oxygen and trace amounts of carbon dioxide. An operational mode that occurs briefly during certain operating conditions, and is characterized by flashes of light and violent bubbling near the cathode, might be attributable to the combustion of hydrogen and oxygen in the electrolyte solution.

Smith, Barton [ORNL; Toops, Todd J [ORNL

2007-12-01

129

Cellular basis for singing motor pattern generation in the field cricket (Gryllus bimaculatus DeGeer).  

PubMed

The singing behavior of male crickets allows analyzing a central pattern generator (CPG) that was shaped by sexual selection for reliable production of species-specific communication signals. After localizing the essential ganglia for singing in Gryllus bimaculatus, we now studied the calling song CPG at the cellular level. Fictive singing was initiated by pharmacological brain stimulation. The motor pattern underlying syllables and chirps was recorded as alternating spike bursts of wing-opener and wing-closer motoneurons in a truncated wing nerve; it precisely reflected the natural calling song. During fictive singing, we intracellularly recorded and stained interneurons in thoracic and abdominal ganglia and tested their impact on the song pattern by intracellular current injections. We identified three interneurons of the metathoracic and first unfused abdominal ganglion that rhythmically de- and hyperpolarized in phase with the syllable pattern and spiked strictly before the wing-opener motoneurons. Depolarizing current injection in two of these opener interneurons caused additional rhythmic singing activity, which reliably reset the ongoing chirp rhythm. The closely intermeshing arborizations of the singing interneurons revealed the dorsal midline neuropiles of the metathoracic and three most anterior abdominal neuromeres as the anatomical location of singing pattern generation. In the same neuropiles, we also recorded several closer interneurons that rhythmically hyper- and depolarized in the syllable rhythm and spiked strictly before the wing-closer motoneurons. Some of them received pronounced inhibition at the beginning of each chirp. Hyperpolarizing current injection in the dendrite revealed postinhibitory rebound depolarization as one functional mechanism of central pattern generation in singing crickets. PMID:23170234

Schöneich, Stefan; Hedwig, Berthold

2012-11-01

130

The Generation of Antiphase Oscillations and Synchrony by a Rebound-Based Vertebrate Central Pattern Generator  

PubMed Central

Many neural circuits are capable of generating multiple stereotyped outputs after different sensory inputs or neuromodulation. We have previously identified the central pattern generator (CPG) for Xenopus tadpole swimming that involves antiphase oscillations of activity between the left and right sides. Here we analyze the cellular basis for spontaneous left–right motor synchrony characterized by simultaneous bursting on both sides at twice the swimming frequency. Spontaneous synchrony bouts are rare in most tadpoles, and they instantly emerge from and switch back to swimming, most frequently within the first second after skin stimulation. Analyses show that only neurons that are active during swimming fire action potentials in synchrony, suggesting both output patterns derive from the same neural circuit. The firing of excitatory descending interneurons (dINs) leads that of other types of neurons in synchrony as it does in swimming. During synchrony, the time window between phasic excitation and inhibition is 7.9 ± 1 ms, shorter than that in swimming (41 ± 2.3 ms). The occasional, extra midcycle firing of dINs during swimming may initiate synchrony, and mismatches of timing in the left and right activity can switch synchrony back to swimming. Computer modeling supports these findings by showing that the same neural network, in which reciprocal inhibition mediates rebound firing, can generate both swimming and synchrony without circuit reconfiguration. Modeling also shows that lengthening the time window between phasic excitation and inhibition by increasing dIN synaptic/conduction delay can improve the stability of synchrony.

Merrison-Hort, Robert; Zhang, Hong-Yan; Borisyuk, Roman

2014-01-01

131

The generation of antiphase oscillations and synchrony by a rebound-based vertebrate central pattern generator.  

PubMed

Many neural circuits are capable of generating multiple stereotyped outputs after different sensory inputs or neuromodulation. We have previously identified the central pattern generator (CPG) for Xenopus tadpole swimming that involves antiphase oscillations of activity between the left and right sides. Here we analyze the cellular basis for spontaneous left-right motor synchrony characterized by simultaneous bursting on both sides at twice the swimming frequency. Spontaneous synchrony bouts are rare in most tadpoles, and they instantly emerge from and switch back to swimming, most frequently within the first second after skin stimulation. Analyses show that only neurons that are active during swimming fire action potentials in synchrony, suggesting both output patterns derive from the same neural circuit. The firing of excitatory descending interneurons (dINs) leads that of other types of neurons in synchrony as it does in swimming. During synchrony, the time window between phasic excitation and inhibition is 7.9 ± 1 ms, shorter than that in swimming (41 ± 2.3 ms). The occasional, extra midcycle firing of dINs during swimming may initiate synchrony, and mismatches of timing in the left and right activity can switch synchrony back to swimming. Computer modeling supports these findings by showing that the same neural network, in which reciprocal inhibition mediates rebound firing, can generate both swimming and synchrony without circuit reconfiguration. Modeling also shows that lengthening the time window between phasic excitation and inhibition by increasing dIN synaptic/conduction delay can improve the stability of synchrony. PMID:24760866

Li, Wen-Chang; Merrison-Hort, Robert; Zhang, Hong-Yan; Borisyuk, Roman

2014-04-23

132

Online Generation of Humanoid Walking Motion based on a Fast Generation Method of Motion Pattern that Follows Desired ZMP  

Microsoft Academic Search

This paper presents an efficient online method to generate humanoid walking motions that satisfy desired upper body trajectories while simultaneously carrying objects. A fast motion pattern generation technique that follows the desired ZMP is adopted. In order to satisfy the control input given online, subsequent motion patterns are updated and connected in a stable manner to the old ones while

Koichi Nishiwaki; Satoshi Kagami; Yasuo Kuniyoshi; Masayuki Inaba; Hirochika Inoue

2002-01-01

133

Regional variations in test requiring patterns of general practitioners in Spain  

PubMed Central

Objective To analyze the requesting patterns for a range of laboratory tests ordered in 2009 from eight laboratories providing services to eight health areas, using appropriate indicators. Design Indicators measured every test request per 1,000 inhabitants, and indicators that measured the number of tests per related test requested by general practitioners were calculated. The savings generated, if each Health Care Department achieved the appropriate indicator standard, were also calculated. Laboratory Information System registers were collected, and indicators were calculated automatically in each laboratory using a data warehouse application. Results There was a large difference in demand for tests by health areas. The ratio of related tests also showed a great variability. The savings generated if each Health Care Department had achieved the appropriate indicator standard were €172,116 for free thyroxine, €18,289 for aspartate aminotransferase, and €62,678 for urea. Conclusions Considerable variability exists in general practitioners' demand for laboratory tests.

2011-01-01

134

Evidence for the involvement of a spinal pattern generator in the control of the genital motor pattern of ejaculation  

Microsoft Academic Search

One of the hypotheses to explain the neural mechanisms underlying rhythmic behaviours suggests that the central nervous system has the intrinsic capacity to produce repetitive, rhythmic output to the muscles involved in the response by means of a neuronal circuit named central pattern generator (CPG). The occurrence of rhythmic motor patterns during ejaculatory behaviour in mammals, which includes the genital

Miguel Carro-Juárez; Silvia L. Cruz; Gabriela Rodr??guez-Manzo

2003-01-01

135

Patterning control budgets for the 32-nm generation incorporating lithography, design, and RET variations  

NASA Astrophysics Data System (ADS)

An important outcome of the 90nm and 65nm device generations was the realization that new methods for predicting and controlling patterning were required to ensure successful transfer for all design rule compliant features through the required process window. This realization led to a strong increase in the use of CD-based and process window aware post-optical proximity correction (OPC) verification in production mask tapeouts. Accurate post-OPC verification is a necessity but many patterning issues could have been detected and removed earlier in the product development lifecycle. Of course, the 45nm and 32nm device generations are only expected to further strain the ability of device manufacturers to predict process control requirements, robust patterning design rules and first-time right reticle enhancement technology (RET) recipes. Therefore, improvements to the traditional process, OPC and design rule prediction/evaluation steps are needed. In this paper we propose a patterning and CD control prediction methodology which incorporates not only the traditional dose, defocus and mask variation parameters but also implements RET parameter variations such as layout edge discretization, model inaccuracy, metrology error and assist feature placement. This methodology allows a more accurate prediction of process control requirements, worst case CD control layout geometries and RET subsystem accuracy/control requirements. Lithography engineers have long operated with specific (if not always fully understood) dose and focus control success requirements. To efficiently determine real worst design situations, we utilize a new methodology for quickly verifying the RET-ability of a lithography process + design rule set + OPC correction recipe based on coupling iterative layout generation with OPC testing. Our aim in this paper is to provide additional engineering rigor to the traditional experience-based OPC success requirements by looking at the total Litho + RET + metrology patterning problem and analyzing the individual component control needs.

Lucas, Kevin; Cork, Chris; Cobb, Jonathan; Ward, Brian; Drapeau, Martin; Zhang, Charlie; Allgair, John; Kling, Mike; Rieger, Mike

2007-03-01

136

Reliability Test Report. Modular Cryogenic Generator.  

National Technical Information Service (NTIS)

Reliability Testing of the LOX-30 Liquid Oxygen Plant was evaluated in accordance with MIL-STD-781. Reliability Tests were divided into Environmental Requirements, Reliability Growth and Reliability Demonstration Tests. Accept/reject criteria for the demo...

R. Ferret

1978-01-01

137

COMPACTEST: A Method to Generate Compact Test Sets for Combinatorial Circuits  

Microsoft Academic Search

Heuristics to aid the derivation of small test sets that detect single stuck-at faults in combinational logic circuits are proposed. The heuristics can be added to existing test pattern generators without compromising fault coverage. Experimental Tesults obtained by adding the proposed heuristics to a simple PODEM procedure and applying it to the ISCAS-85 and ISCAS-89 benchmark circuits are presented to

Irith Pomeranz; Lakshmi N. Reddy; Sudhakar M. Reddy

1991-01-01

138

Electronic Test Generators: What Current Programs Can Do for Teachers.  

ERIC Educational Resources Information Center

Reviews the current status of computerized test generators, which can assist teachers in the development and writing of good tests. Provides comparative strengths and weaknesses of 11 major test-generating programs. Shows how word processors and database programs can also assist the production of tests. (HB)

Vockell, Edward L.; Fiore, Douglas J.

1993-01-01

139

Sparse Serial Tests of Uniformity for Random Number Generators  

Microsoft Academic Search

Dierent versions of the serial test for testing the uniformity and independence of vectors of successive values produced by a (pseudo)random number generator are studied. These tests partition the t-dimensional unit hypercube into k cubic cells of equal volume, generate n points (vectors) in this hypercube, count how many points fall in each cell, and compute a test statistic dened

RICHARD SIMARD; STEFAN WEGENKITTL

2002-01-01

140

Regressive model approach to the generation of test trajectories  

Microsoft Academic Search

One aspect of system safety assurance is the application of large test sets. To aid in the development of test cases, researchers have investigated automated test generation systems which decrease the time and cost of acquiring new tests. Many automated systems currently exist, but few address the generation of trajectories of data. A trajectory is defined as a series of

Brian J. Taylor; Bojan Cukic

2000-01-01

141

Regressive Model Approach to the Generation of Test Trajectories  

Microsoft Academic Search

One aspect of system safety assurance is the application of large test sets. To aid in the development of test cases, researchers have investigated automated test generation systems which decrease the time and cost of acquiring new tests. Many automated systems currently exist, but few address the generation of trajectories of data. A trajectory is defined as a series of

Brian J. Taylor; Bojan Cukic

2009-01-01

142

WISE: Automated test generation for worst-case complexity  

Microsoft Academic Search

Program analysis and automated test generation have primarily been used to find correctness bugs. We present complexity testing, a novel automated test generation tech- nique to find performance bugs. Our complexity testing al- gorithm, which we call WISE (Worst-case Inputs from Sym- bolic Execution), operates on a program accepting inputs of arbitrary size. For each input size, WISE attempts to

Jacob Burnim; Sudeep Juvekar; Koushik Sen

2009-01-01

143

Testing the Tests: Using Random Number Generators to Improve Empirical Tests  

Microsoft Academic Search

The implementer of an empirical test for random number generators is faced with some difficult problems, especially if the\\u000a test is based on a statistic which is known only approximately: How can the test be tested? How can the approximation be improved?\\u000a When is it good enough? A number of principles can be applied to these problems. These principles are

Paul Leopardi

144

Generation of crystal-structure transverse patterns via a self-frequency-doubling laser.  

PubMed

Two-dimensional (2D) visible crystal-structure patterns analogous to the quantum harmonic oscillator (QHO) have been experimentally observed in the near- and far-fields of a self-frequency-doubling (SFD) microchip laser. Different with the fundamental modes, the localization of the SFD light is changed with the propagation. Calculation based on Hermite-Gaussian (HG) functions and second harmonic generation theory reproduces well the patterns both in the near- and far-field which correspond to the intensity distribution in coordinate and momentum spaces, respectively. Considering the analogy of wave functions of the transverse HG mode and 2D harmonic oscillator, we propose that the simple monolithic SFD lasers can be used for developing of new materials and devices and testing 2D quantum mechanical theories. PMID:23336067

Yu, Haohai; Zhang, Huaijin; Wang, Yicheng; Wang, Zhengping; Wang, Jiyang; Petrov, V

2013-01-01

145

Application of Sigma7500 pattern generator to X architecture and 45-nm generation mask making  

NASA Astrophysics Data System (ADS)

The mask cost is increasing substantially from generation to generation. Hence, reducing the mask cost is one of the most critical needs in developing a new generation of technology. Compared with variable shaped beam (VSB) e-beam tools, laser writers have the advantage of higher throughput and lower cost. Moreover, the writing time is not dependent on feature count but on the area written. Additionally the FEP-171 resist, which is used for the DUV laser writer, is also the resist used for VSB writers. This enables process sharing and reduces the number of processes needed for mask manufacturing. Finally the laser writer is expected to print Manhattan and X-architecture features with no major differences. Whereas, VSB e-beam tools take longer to write, if X features are included with Manhattan-type features. The inclusion of X features also worsens CD uniformity when written with VSB e-beam tools. The Sigma7500 DUV laser writer uses partially coherent imaging of a spatial light modulator (SLM) to maximize resolution, while providing 4-pass and 2-pass printings, corner enhancement, and grid matching. These functions are evaluated and the results are reported in this paper. Evaluation data shows that the global CD uniformity of dense line/space and isolated spaces is around 6 nm (3?) for features at 0-, 45-, 90-, and 135-degree angles, which are used in the X architecture. The resolution of lines and spaces can both reach 150 nm. Based on our evaluation, the Sigma7500 can meet both critical 65-nm and sub-critical 45-nm generation mask specifications and reduces the writing cost by 40%. The writing time for X architecture patterns can be reduced by at least a factor of two as compared to VSB systems, while the CD performance remains comparable. However, the pattern fidelity is slightly worse and the CD of 45- and 135-degree lines is difficult to adjust independently. In addition, the Sigma7500 comes with a data-sizing function (ProcessEqualizer) to compensate for global CD signatures, but the potential impact of data sizing on OPC accuracy is a concern and it must be evaluated. Evaluation data shows that the Sigma7500 is capable of 45-nm node sub-critical mask production. Its advantages in high productivity and acceptable CD control should provide a solution to reduce the mask cost of advanced nodes.

Yao, Ming-Jiun; Wang, Tzu-Yi; Chen, Chia-Jen; Lee, Hsin-Chang; Ku, Yao-Ching

2007-05-01

146

On Statistical Testing of Random Numbers Generators  

Microsoft Academic Search

Maurer's test is nowadays a basic statistical tool for testing physical random number gen- erators in cryptographic applications. Based on a statistical analysis of this test we propose simple and efiective methods for its improvement. These methods are related to the m - spacing technique common in goodness-of-flt problems and the L - leave out method used for a noise

Fida El Haje; Yuri Golubev; Pierre-yvan Liardet; Yannick Teglia

2006-01-01

147

Generating program inputs for database application testing  

Microsoft Academic Search

Testing is essential for quality assurance of database applications. Achieving high code coverage of the database application is important in testing. In practice, there may exist a copy of live databases that can be used for database application testing. Using an existing database state is desirable since it tends to be representative of real-world objects' characteristics, helping detect faults that

Kai Pan; Xintao Wu; Tao Xie

2011-01-01

148

40 CFR 86.1333-2010 - Transient test cycle generation.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Transient test cycle generation. 86.1333-2010 Section... Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous...Procedures § 86.1333-2010 Transient test cycle generation. (a) Generating...

2013-07-01

149

Generation of Oriented Buckling Patterns by Modulation of Local Elastic Moduli  

Microsoft Academic Search

Wrinkling patterns based on elastic instabilities are interesting due to the spontaneous formation of relief structures that consists of a dominant periodicity. While a wide variety of soft materials has been utilized to generate surface buckling patterns, alignment of these structures has only been demonstrated previously through pre-defined topographic patterns. In this contribution, we introduce a new methodology to producing

Edwin Chan; Alfred Crosby

2006-01-01

150

Biped walking pattern generation by using preview control with virtual plane method  

Microsoft Academic Search

This paper describes a biped walking pattern generation by using preview control with virtual plane method. It is important for biped robots to generate desired walking patterns which satisfy given Zero-Moment-Point (ZMP) trajectories. Solving ZMP equation is one of the key issues in the biped walking research field. Many kinds of the solutions have ever been proposed. One of the

Shuhei Shimmyo; Tomoya Sato; Kouhei Ohnishi

2010-01-01

151

Note: The full function test explosive generator.  

PubMed

We have conducted three tests of a new pulsed power device called the full function test. These tests represented the culmination of an effort to establish a high energy pulsed power capability based on high explosive pulsed power (HEPP) technology. This involved an extensive computational modeling, engineering, fabrication, and fielding effort. The experiments were highly successful and a new U.S. record for magnetic energy was obtained. PMID:20370232

Reisman, D B; Javedani, J B; Griffith, L V; Ellsworth, G F; Kuklo, R M; Goerz, D A; White, A D; Tallerico, L J; Gidding, D A; Murphy, M J; Chase, J B

2010-03-01

152

Note: The full function test explosive generator  

NASA Astrophysics Data System (ADS)

We have conducted three tests of a new pulsed power device called the full function test. These tests represented the culmination of an effort to establish a high energy pulsed power capability based on high explosive pulsed power (HEPP) technology. This involved an extensive computational modeling, engineering, fabrication, and fielding effort. The experiments were highly successful and a new U.S. record for magnetic energy was obtained.

Reisman, D. B.; Javedani, J. B.; Griffith, L. V.; Ellsworth, G. F.; Kuklo, R. M.; Goerz, D. A.; White, A. D.; Tallerico, L. J.; Gidding, D. A.; Murphy, M. J.; Chase, J. B.

2010-03-01

153

Reflective electron beam lithography: lithography results using CMOS controlled digital pattern generator chip  

NASA Astrophysics Data System (ADS)

Maskless electron beam lithography can potentially extend semiconductor manufacturing to the 10 nm logic (16 nm half pitch) technology node and beyond. KLA-Tencor is developing Reflective Electron Beam Lithography (REBL) technology targeting high-volume 10 nm logic node performance. REBL uses a novel multi-column wafer writing system combined with an advanced stage architecture to enable the throughput and resolution required for a NGL system. Using a CMOS Digital Pattern Generator (DPG) chip with over one million microlenses, the system is capable of maskless printing of arbitrary patterns with pixel redundancy and pixel-by-pixel grayscaling at the wafer. Electrons are generated in a flood beam via a thermionic cathode at 50-100 keV and decelerated to illuminate the DPG chip. The DPG-modulated electron beam is then reaccelerated and demagnified 80-100x onto the wafer to be printed. Previously, KLA-Tencor reported on the development progress of the REBL tool for maskless lithography at and below the 10 nm logic technology node. Since that time, the REBL team has made good progress towards developing the REBL system and DPG for direct write lithography. REBL has been successful in manufacturing a CMOS controlled DPG chip with a stable charge drain coating and with all segments functioning. This DPG chip consists of an array of over one million electrostatic lenslets that can be switched on or off via CMOS voltages to pattern the flood electron beam. Testing has proven the validity of the design with regards to lenslet performance, contrast, lifetime, and pattern scrolling. This chip has been used in the REBL demonstration platform system for lithography on a moving stage in both PMMA and chemically amplified resist. Direct imaging of the aerial image has also been performed by magnifying the pattern at the wafer plane via a mag stack onto a YAG imaging screen. This paper will discuss the chip design improvements and new charge drain coating that have resulted in a functional DPG chip and will evaluate the current chip performance on the REBL system. Print results for line/space and device test patterns at the 100nm node will be presented.

Gubiotti, Thomas; Sun, Jeff Fuge; Freed, Regina; Kidwingira, Francoise; Yang, Jason; Bevis, Chris; Carroll, Allen; Brodie, Alan; Tong, William M.; Lin, Shy-Jay; Wang, Wen-Chuan; Haspeslagh, Luc; Vereecke, Bart

2013-03-01

154

Gamete imprinting: setting epigenetic patterns for the next generation  

Microsoft Academic Search

The acquisition of genomic DNA methylation patterns, including those important for development, begins in the germ line. In particular, imprinted genes are differentially marked in the developing male and female germ cells to ensure parent-of-origin-specific expression in the offspring. Abnormalities in imprints are associated with perturbations in growth, placental function, neurobehavioural processes and carcinogenesis. Based, for the most part, on

Jacquetta M. Trasler

2006-01-01

155

Generative Models of Segregation: Investigating Model-Generated Patterns of Residential Segregation by Ethnicity and Socioeconomic Status  

Microsoft Academic Search

This article considers the potential for using agent models to explore theories of residential segregation in urban areas. Results of generative experiments conducted using an agent-based simulation of segregation dynamics document that varying a small number of model parameters representing constructs from urban-ecological theories of segregation can generate a wide range of qualitatively distinct and substantively interesting segregation patterns. The

MARK FOSSETT

2011-01-01

156

Module Level Weighted Random Patterns  

Microsoft Academic Search

The paper describes a module levelself-test architecture that uses weightedrandom patterns. A pseudorandom pattern generator (PRPG) is usedto generate equally likely patterns that are then transformed toweighted patterns by a universal weighting generator. The modulebeing tested is assumed to be composed of a number of chips all ofwhich have been designed to support a scan test. The signature iscollected by

Jacob Savir

1997-01-01

157

Evaluation of a high-dose extended multipass gray writing system for 130-nm pattern generation  

NASA Astrophysics Data System (ADS)

Recent developments in electron-beam (e-beam) systems and mask-writing strategies facilitate pattern generation for the 130-nm IC generation. The MEBESR 5500 pattern generation system incorporates a high-dose electron optical system and a high-throughput writing strategy, Multipass Gray-II (MPG-II). We evaluate the effectiveness of these innovations by three criteria: improved resolution, improved critical dimension (CD) control, and increased throughput. The conclusions of this paper are based on results from extensive modeling, test masks, and factory acceptance masks. Mask resist choice and processing have been optimized for the MEBES 5500 system. A consequence of these improvements is greater productivity for 150 nm devices and early development of 130 nm devices. The MEBES 5500 system uses a high-dose gun and electron optical system. The maximum current density that can be delivered to the mask is 800 A/cm2, twice the value of previous MEBES systems. Without loss of throughput, it is possible to increase the dose deposited in the resist, while using smaller e-beam sizes. These capabilities are exploited to improve printing of submicrometer features, including 200 nm-scale optical proximity correction (OPC) patterns. At small data addresses (<17.1 nm), the MPG-II writing strategy provides twice the throughput of the existing multipass gray (MPG) strategy with the same instrument, and 16X the throughput of traditional single-pass printing (SPP) with the MEBES 4500 system. The fundamentals of the MPG-II strategy are described, as well as throughput and lithographic results.

Chabala, Jan M.; Weaver, Suzanne; Alexander, David; Pearce-Percy, Henry T.; Lu, Maiying; Cole, Damon M.; Abboud, Frank E.

2000-07-01

158

Directed Generation of Test Data for Static Semantics Checker  

NASA Astrophysics Data System (ADS)

We present an automatic method, named SemaTESK, for generation of test sets for a translator front end. We focus on the validation and verification of static semantics checker. Most the know methods for semantics test generation produce test suites by filtering a pre-generated set of random texts in the target language. In contrast, SemaTESK allows to generate tests for context conditions directly. It significantly reduces generation time and allows reaching completeness criteria defined in the paper. The presented method to specify static semantics allows to formalize informal requirements described in normative documents (e.g. standard). The method includes SRL notation for compact formal specification of context conditions and STG tool for efficient generation of test suite from SRL specification.

Arkhipova, M. V.; Zelenov, S. V.

159

32 nm imprint masks using variable shape beam pattern generators  

NASA Astrophysics Data System (ADS)

Imprint lithography has been included on the ITRS Lithography Roadmap at the 32, 22 and 16 nm nodes. Step and Flash Imprint Lithography (S-FIL ®) is a unique method that has been designed from the beginning to enable precise overlay for creating multilevel devices. A photocurable low viscosity monomer is dispensed dropwise to meet the pattern density requirements of the device, thus enabling imprint patterning with a uniform residual layer across a field and across entire wafers. Further, S-FIL provides sub-100 nm feature resolution without the significant expense of multi-element, high quality projection optics or advanced illumination sources. However, since the technology is 1X, it is critical to address the infrastructure associated with the fabrication of templates. For sub-32 nm device manufacturing, one of the major technical challenges remains the fabrication of full-field 1x templates with commercially viable write times. Recent progress in the writing of sub-40 nm patterns using commercial variable shape e-beam tools and non-chemically amplified resists has demonstrated a very promising route to realizing these objectives, and in doing so, has considerably strengthened imprint lithography as a competitive manufacturing technology for the sub 32nm node. Here we report the first imprinting results from sub-40 nm full-field patterns, using Samsung's current flash memory production device design. The fabrication of the template is discussed and the resulting critical dimension control and uniformity are discussed, along with image placement results. The imprinting results are described in terms of CD uniformity, etch results, and overlay.

Selinidis, Kosta; Thompson, Ecron; Schmid, Gerard; Stacey, Nick; Perez, Joseph; Maltabes, John; Resnick, Douglas J.; Yeo, Jeongho; Kim, Hoyeon; Eynon, Ben

2008-06-01

160

Mirror-based pattern generation for maskless lithography  

Microsoft Academic Search

In this paper, we consider the composition of integrated circuit patterns using dense arrays of mirrors. Typically the mirrors are 10–100 wavelengths in size and are demagnified some to form slightly sub-resolution spots or pixels at the wafer. The mirrors are actuated to modulate the light intensity. We consider both pure phase mirrors, moved in piston-like fashion, and tilting mirrors,

William G. Oldham; Yashesh Shroff

2004-01-01

161

Generating arbitrary chemical patterns for multipoint dosing of single cells.  

PubMed

Living cells reside within anisotropic microenvironments that orchestrate a broad range of polarized responses through physical and chemical cues. To unravel how localized chemical signals influence complex behaviors, tools must be developed for establishing patterns of chemical gradients that vary over subcellular dimensions. Here, we present a strategy for addressing this critical need in which an arbitrary number of chemically distinct, subcellular dosing streams are created in real time within a microfluidic environment. In this approach, cells are cultured on a thin polymer membrane that serves as a barrier between the cell-culture environment and a reagent chamber containing multiple reagent species flowing in parallel under low Reynolds number conditions. Focal ablation of the membrane creates pores that allow solution to flow from desired regions within this reagent pattern into the cell-culture chamber, resulting in narrow, chemically distinct dosing streams. Unlike previous dosing strategies, this system provides the capacity to tailor arbitrary patterns of reagents on the fly to suit the geometry and orientation of specific cells. PMID:23427919

Hoppe, Todd J; Moorjani, Samira G; Shear, Jason B

2013-04-01

162

40 CFR 53.42 - Generation of test atmospheres for wind tunnel tests.  

Code of Federal Regulations, 2010 CFR

...false Generation of test atmospheres for wind tunnel tests. 53.42 Section 53...42 Generation of test atmospheres for wind tunnel tests. (a) A vibrating...shall consist of a blower system and a wind tunnel having a test section of...

2010-07-01

163

40 CFR 53.42 - Generation of test atmospheres for wind tunnel tests.  

Code of Federal Regulations, 2010 CFR

...false Generation of test atmospheres for wind tunnel tests. 53.42 Section 53...42 Generation of test atmospheres for wind tunnel tests. (a) A vibrating...shall consist of a blower system and a wind tunnel having a test section of...

2009-07-01

164

Automated test-data generation for exception conditions  

Microsoft Academic Search

SUMMARY This paper presents a technique for automatically generating test-data to test exceptions. The approach is based on the application of a dynamic global optimization based search for the required test-data. The authors' work has focused on test-data generation for safety-critical systems. Such systems must be free from anomalous and uncontrolled behaviour. Typically, it is easier to prove the absence

Nigel Tracey; John A. Clark; Keith Mander; John A. Mcdermid

2000-01-01

165

Interference pattern generation in evanescent electromagnetic waves for nanoscale lithography using waveguide diffraction gratings  

SciTech Connect

The generation of interference patterns of evanescent electromagnetic waves with an essentially subwavelength period using dielectric waveguide diffraction gratings is considered. Using simulations within the framework of the electromagnetic theory, the possibility of obtaining high-quality interference patterns due to enhancement of evanescent diffraction orders under resonance conditions is demonstrated. The contrast of the interference patterns in the case of TE polarisation of the incident wave is close to unity. The field intensity in the near-field interference maxima exceeds the intensity of the incident wave by 25-100 times. The possibility of generation of the interference patterns of evanescent waves corresponding to higher diffraction orders is shown. The use of higher orders reduces the requirements to the fabrication technology and allows generation of interference patterns with a high spatial frequency, using diffraction gratings with a low spatial frequency. Examples of generating interference patters with periods six times smaller than those of the used diffraction gratings are presented. (nanolithography)

Bezus, E A; Doskolovich, L L; Kazanskii, N L [Institute for Image Processing Systems, Russian Academy of Sciences, Samara (Russian Federation)

2011-08-31

166

Optical test alignment using computer generated holograms  

Microsoft Academic Search

Measurement systems for optical surfaces that lack axisymmetry are notoriously difficult to align and have limited accuracy. This paper describes a technique that uses a single CGH to act as null lens for measuring the aspheric surface, at the same time as it projects alignment marks into space that can be used for aligning the test. By providing reference features

Jim Burge; Peter Koudelka

167

Logic systems for path delay test generation  

Microsoft Academic Search

The authors present an algorithmic derivation of logic systems for solving path delay test problems. In these logic systems, the state of a signal represents any possible situation that can occur during two consecutive vectors. Starting from a set of valid input states, a state transition graph is constructed to enumerate all possible states produced by Boolean gates. Specifics of

Soumitra Bose; Prathima Agrawal; Vishwani D. Agrawal

1993-01-01

168

Generation and patterning of Si nanoparticles by femtosecond laser pulses  

NASA Astrophysics Data System (ADS)

The unique optical properties of nanoparticles are highly sensitive in respect to particle shapes, sizes, and localization on a sample. This demands for a fully controlled fabrication process. The use of femtosecond laser pulses to generate and transfer nanoparticles from a bulk target towards a collector substrate is a promising approach. This process allows a controlled fabrication of spherical nanoparticles with a very smooth surface. Several process parameters can be varied to achieve the desired nanoparticle characteristics. In this paper, the influence of two of these parameters, i.e. the applied pulse energy and the laser beam shape, on the generation of Si nanoparticles from a bulk Si target are studied in detail. By changing the laser intensity distribution on the target surface one can influence the dynamics of molten material inducing its flow to the edges or to the center of the focal spot. Due to this dynamics of molten material, a single femtosecond laser pulse with a Gaussian beam shape generates multiple spherical nanoparticles from a bulk Si target. The statistical properties of this process, with respect to number of generated nanoparticles and laser pulse energy are investigated. We demonstrate for the first time that a ring-shaped intensity distribution on the target surface results in the generation of a single silicon nanoparticle with a controllable size. Furthermore, the generated silicon nanoparticles presented in this paper show strong electric and magnetic dipole resonances in the visible and near-infrared spectral range. Theoretical simulations as well as optical scattering measurements of single silicon nanoparticles are discussed and compared.

Zywietz, Urs; Reinhardt, Carsten; Evlyukhin, Andrey B.; Birr, Tobias; Chichkov, Boris N.

2014-01-01

169

Automatic GUI test generation for smartphone applications - an evaluation  

Microsoft Academic Search

We present the results of an evaluation where we studied the effectiveness of automatic test generation for graphical user interface (GUI) testing of smartphone applications. To describe the context of our evaluation, the tools and the test model library we have developed for the evaluation are also presented. The library contains test models for basic S60 applications, such as camera,

Antti Jääskeläinen; Mika Katara; Antti Kervinen; Mika Maunumaa; Tuula Pääkkönen; Tommi Takala; Heikki Virtanen

2009-01-01

170

Computer-Assisted Generation of Patterns and Virtual Reality Techniques for Fashion Design  

NASA Astrophysics Data System (ADS)

We present a methodology for the design of aesthetic patterns and their visualization on virtual clothes. Generated patterns are directly mapped on the dress of a virtual mannequin. Furthermore, patterns sets may be interactively mapped on the virtual dress using a specific 3D interaction technique called Back-and-Forth. Pattern generation involves different mathematical approaches such as iterated function systems (IFS) and nonlinear trajectory models. Both model parameters and color space exploration is performed through a simple user interface. This work contributes to promote both computer assistance in the context of mass customization for fashion design.

Naud, Mickael; Richard, Paul; Chapeau-Blondeau, François

2009-03-01

171

Automated Test Input Generation for Software That Consumes ORM Models  

NASA Astrophysics Data System (ADS)

Software tools that analyze and generate code from ORM conceptual schemas are highly susceptible to feature interaction bugs. When testing such tools, test suites are needed that cover many combinations of features, including combinations that rarely occur in practice. Manually creating such a test suite is extremely labor-intensive, and the tester may fail to cover feasible feature combinations that are counter-intuitive or that rarely occur. This paper describes ATIG, a prototype tool for automatically generating test suites that cover diverse combinations of ORM features. ATIG makes use of combinatorial testing to optimize coverage of select feature combinations within constraints imposed by the need to keep the sizes of test suites manageable. We have applied ATIG to generate test inputs for an industrial strength ORM-to-Datalog code generator. Initial results suggest that it is useful for finding feature interaction errors in tools that operate on ORM models.

McGill, Matthew J.; Stirewalt, R. E. Kurt; Dillon, Laura K.

172

VanetMobiSim: generating realistic mobility patterns for VANETs  

Microsoft Academic Search

In this paper, we present and describe VanetMobiSim, a generator of realistic vehicular movement traces for telecommunication networks simulators. VanetMobiSim mobility description is validated by illustrating how the interaction between featured macro- and micro-mobility is able to reproduce typical phenomena of vehicular traffic.

Jérôme Härri; Fethi Filali; Christian Bonnet; Marco Fiore

2006-01-01

173

Converging Laser Generated Ultrasonic Waves using Annular Patterns Irradiation  

NASA Astrophysics Data System (ADS)

We report on a contactless method to focus laser generated bulk and surface ultrasound waves in the thermo-elastic coupling mode by annular shaped illumination. By using a spatial light modulator (SLM) the beam profile of a pulsed picoseconds laser was shaped to annular forms flexibly and further rings with a thickness of 50 ?m and a generation energy as low as 2 mJ were generated on the surface of aluminum plates. The annular shapes have been used to focus acoustic waves toward the center. In this work, a photorefractive adaptive interferometer set up based on Two-Wave Mixing in a fast BSO crystal was used to probe and detect the converging acoustic pulses at the center of the laser generated rings. By moving the detection point about 1 mm out of the ring epicenter, the amplitude of bulk and surface waves drop quickly which shows the converging evidence of the acoustic waves in the ring center. For a 3 mm thick aluminum plate, the ring size from 1 mm to 10 mm was scanned. The optimum ring diameter and the focal length of the acoustic waves along the central axis were found. Applications of this technique in subsurface defects detection as well as sample thickness measurement are investigated.

Zamiri, S.; Reitinger, B.; Bauer, S.; Burgholzer, P.

2014-06-01

174

D0 Experimental Area Emergency Backup Power and Generator Test  

Microsoft Academic Search

The DO experimental area has a generator designated as emergency power. This generator provides power for critical loads and starts automatically upon loss of commercial power. This note concerns the testing of this generator. A list of loads is attached to this note. One of the loads on the emergency power grid is a 10KVA Uninterruptable Power Supply(UPS). The UPS

D. Markley

1991-01-01

175

Techniques for empirical testing of parallel random number generators  

Microsoft Academic Search

Parallel computers are now commonly used for computational science and engineering, and many applications in these areas use random number generators. For some applications, such as large-scale Monte Carlo simulations, it is crucial that the random number generator have good randomness properties. Many programs are available for testing the quality of sequential random number generators, but very little work has

Paul D. Coddington; Sung-Hoon Ko

1998-01-01

176

Test generation for MOS circuits using D-algorithm  

Microsoft Academic Search

An application of the D-algorithm in generating tests for MOS circuit faults is described. The MOS circuits considered are combinational and acyclic but may contain transmission gates and buses. Tests are generated for both, the stuck type faults and the transistor faults (open and short). A logic model is derived for the MOS circuits. In addition to the conventional logic

Sunil K. Jain; Vishwani D. Agrawal

1983-01-01

177

Synchronizing sequences and symbolic traversal techniques in test generation  

Microsoft Academic Search

Asynchronizing sequence drives a circuit from an arbitrary power-up state into a unique state. Test generation on a circuit without a reset state can be much simplified if the circuit has a synchronizing sequence. In this article, a framework and algorithms for test generation based on themultiple observation time strategy are developed by taking advantage of synchronizing sequences. Though it

Hyunwoo Cho; Seh-woong Jeong; Fabio Somenzi; Carl Pixley

1993-01-01

178

VHDL Fault Simulation and Automatic Test Pattern Generation Requirements Document.  

National Technical Information Service (NTIS)

This document describes the requirements for a design automation tool that performs fault simulation and fault grading using the Very High Speed Integrated Circuit (VHSIC) Hardware Description Language (VHDL). The goal is to develop a tool which can autom...

B. W. Johnson D. T. Smith T. A. DeLong

1996-01-01

179

Testing to Characterize the Advanced Stirling Radioisotope Generator Engineering Unit  

NASA Technical Reports Server (NTRS)

The Advanced Stirling Radioisotope Generator (ASRG), a high efficiency generator, is being considered for space missions. Lockheed Martin designed and fabricated an engineering unit (EU), the ASRG EU, under contract to the Department of Energy. This unit is currently undergoing extended operation testing at the NASA Glenn Research Center to generate performance data and validate life and reliability predictions for the generator and the Stirling convertors. It has also undergone performance tests to characterize generator operation while varying control parameters and system inputs. This paper summarizes and explains test results in the context of designing operating strategies for the generator during a space mission and notes expected differences between the EU performance and future generators.

Lewandowski, Edward; Schreiber, Jeffrey

2010-01-01

180

Patterns of rock fragment cover generated by tillage erosion  

NASA Astrophysics Data System (ADS)

Intensively cultivated areas in the upper part of the Guadalentin catchment (southeast Spain) show a systematic spatial pattern of surface rock fragment cover ( Rc). The objective of this paper is to quantify and to explain this spatial rock fragment cover pattern. Therefore, a map of an intensively cultivated area of 5 km 2 was digitised, and for each pixel total topographic curvature was calculated. Next, rock fragment cover was determined photographically at 35 sites with a range of total slope curvatures. A linear relation between total curvature and rock fragment cover was found, except for narrow concavities. It was hypothesised that this pattern can be explained by a significant net downslope movement of rock fragments and fine earth by tillage. The displacement distances of rock fragments by tillage with a duckfoot chisel were measured by monitoring the displacement of tracers (painted rock fragments and aluminium cubes) on 5 sites having different slopes. The rare of tillage erosion for one tillage pass with a duckfoot chisel, expressed by the diffusion constant ( k), equals 282 kg/m for up and downslope tillage and only 139 kg/m for contour tillage. Nomograms indicate that mean denudation rates in almond groves due to tillage erosion (3 to 5 tillage passes per year) can easily amount to 1.5-2.6 mm/year for contour tillage and up to 3.6-5.9 mm/year for up- and downslope tillage for a field, 50 m long and having a slope of 20%. These figures are at least one order of magnitude larger than reported denudation rates caused by water erosion in similar environments. Hence tillage erosion contributes significantly to land degradation. The downslope soil flux induced by tillage not only causes considerable denudation on topographic convexities (hill tops and spurs) and upper field boundaries but also an important sediment accumulation in topographic concavities (hollows and valley bottoms) and at lower field boundaries. Kinetic sieving (i.e. the upward migration of rock fragments) by the tines of the duckfoot chisel also concentrates the largest rock fragments in the topsoil in such a way that a rock fragment mulch develops in narrow valleys and at the foot of the slopes. These results clearly indicate that tillage erosion is the main process responsible for the observed rock fragment cover pattern in the study area. Since the study area is representative for many parts of southern Spain where almond groves have expanded since 1970, the results have a wider application. They show to what extent intensive tillage of steep slopes has contributed to the increase in soil degradation, to changes in hillslope morphology (i.e. strong denudation of convexities, development of lynchets and rapid infilling of narrow valley bottoms) and to the development of rock fragment cover patterns which control the spatial variability of the hydrological and water erosion response within such landscapes.

Poesen, Jean; Wesemael, Bas van; Govers, Gerard; Martinez-Fernandez, José; Desmet, Philippe; Vandaele, Karel; Quine, Timothy; Degraer, Greet

1997-03-01

181

A Genetic Algorithm-specific Test Of Random Generator Quality  

Microsoft Academic Search

It has been shown in past research that pseudo-random number generator (PRNG) quality can impact the performance of sim-ple genetic algorithms (GAs). However, stan-dard empirical tests of random generator quality are not good predictors of when such impacts are likely to occur. In this paper, we introduce a new test of random genera-tor quality, tailored to speci c instances of

Mark M. Meysenburg; Daniel Hoelting; Duane Mcelvain; James A. Foster

2002-01-01

182

Morphodynamics and anabranching patterns generated in the Madeira River, Brazil  

NASA Astrophysics Data System (ADS)

The Madeira River is the largest tributary in water discharge and sediment transport of the Amazon River. At present, this river is at the center of a controversial political discussion because the Brazilian government is building two hydroelectric plants on the Bolivia-Brazil border, flooding a long reach from near Cachuela Esperanza in the tributary Beni River, close to the Brazil-Bolivia border, up to Porto Velho. We present results from three field expeditions carried out in July-August 2011, December 2012 and March 2013. The main scope of this article is to disseminate the environmental threat suffered by the Madeira from regulation/disruption, and to present preliminary results on the geomorphologic characteristics of the Madeira channel and floodplain. Using historical radar and satellite imagery, the floodplain morpho-sedimentary units and morphology of the channel were assessed and quantified. Sediment bed and bank sampling, bathymetric surveys and velocity measurements were recorded using a single beam echo sounder and an acoustic Doppler current profiler (ADCP), respectively. Velocity data were analyzed using TRDI's WinRiverII and a MATLAB-based software package Velocity Mapping Tool. We consider that the Madeira River offers some ideal conditions to provide information on critical conditions and geomorphologic thresholds in mega-rivers. The Madeira River has been classified as a simple to moderate anabranching low-sinuosity river. The Madeira flows through a relatively simple pattern, alternating straight reaches with others that exhibit an incipient tendency to anabranch. Single beam and ADCP data yields insight into the bathymetry and flow characteristics in the channel through straight, pseudo-meandering, and anabranching stretches. We studied in detail three selected three reaches zones where three primary mechanisms for anabranching were identified: a) branches upstream and downstream in box shape pseudo-meanders; b) simple branch patterns developing downstream a straight single channel reach; and c) branches in sinuous-second order lateral channels. Velocity maps and an analysis of secondary currents provide information on the three-dimensional flows of water within the channel indicating that bed and channel morphology affect hydraulic characteristics. Several cross sections present unusually deep pools up to ~80m depth in the outer bank and significant increases in the local water slope. These are related to geological constraints, which manifest in the over deepening from the preferentially downwards secondary flow, exacerbating erosion. The anabranching patterns in large rivers such as the Madeira are not just controlled by intrinsic morphodynamics and hydraulic geometry variables but though a variety of interactions with the architecture of the floodplain and the control exerted by older fluvial geomorphological units.

Latrubesse, E. M.; Bonthius, C.; Abad, J. D.; Stevaux, J.; Filizola, N.; Frias, C. E.

2013-12-01

183

Model-Driven Test Generation of Distributed Systems  

NASA Technical Reports Server (NTRS)

This report describes a novel test generation technique for distributed systems. Utilizing formal models and formal verification tools, spe cifically the Symbolic Analysis Laboratory (SAL) tool-suite from SRI, we present techniques to generate concurrent test vectors for distrib uted systems. These are initially explored within an informal test validation context and later extended to achieve full MC/DC coverage of the TTEthernet protocol operating within a system-centric context.

Easwaran, Arvind; Hall, Brendan; Schweiker, Kevin

2012-01-01

184

Quantitative Analysis of the Drosophila Segmentation Regulatory Network Using Pattern Generating Potentials  

PubMed Central

Cis-regulatory modules that drive precise spatial-temporal patterns of gene expression are central to the process of metazoan development. We describe a new computational strategy to annotate genomic sequences based on their “pattern generating potential” and to produce quantitative descriptions of transcriptional regulatory networks at the level of individual protein-module interactions. We use this approach to convert the qualitative understanding of interactions that regulate Drosophila segmentation into a network model in which a confidence value is associated with each transcription factor-module interaction. Sequence information from multiple Drosophila species is integrated with transcription factor binding specificities to determine conserved binding site frequencies across the genome. These binding site profiles are combined with transcription factor expression information to create a model to predict module activity patterns. This model is used to scan genomic sequences for the potential to generate all or part of the expression pattern of a nearby gene, obtained from available gene expression databases. Interactions between individual transcription factors and modules are inferred by a statistical method to quantify a factor's contribution to the module's pattern generating potential. We use these pattern generating potentials to systematically describe the location and function of known and novel cis-regulatory modules in the segmentation network, identifying many examples of modules predicted to have overlapping expression activities. Surprisingly, conserved transcription factor binding site frequencies were as effective as experimental measurements of occupancy in predicting module expression patterns or factor-module interactions. Thus, unlike previous module prediction methods, this method predicts not only the location of modules but also their spatial activity pattern and the factors that directly determine this pattern. As databases of transcription factor specificities and in vivo gene expression patterns grow, analysis of pattern generating potentials provides a general method to decode transcriptional regulatory sequences and networks.

Richards, Adam; McCutchan, Michael; Wakabayashi-Ito, Noriko; Hammonds, Ann S.; Celniker, Susan E.; Kumar, Sudhir; Wolfe, Scot A.; Brodsky, Michael H.; Sinha, Saurabh

2010-01-01

185

Tests and evaluation of multihundred watt thermoelectric generators at JPL  

NASA Technical Reports Server (NTRS)

The multihundred watt (MHW) thermoelectric generator, based on silicon-germanium thermoelectric technology, delivers a nominal power output of 150 watts with an efficiency of about 6%. The two Voyager space probes each use three such generators assembled in tandem on a boom. A total of seven MHW type thermoelectric generators were tested at JPL in support of the Voyager project. The tests consisted of: (1) parametric evaluation of the electrical characteristics of the devices over a wide range of output voltage for different values of input power, different operating ambients (air, vacuum), and different internal environments (argon, helium, xenon, mixture of these gases, and vacuum) at different pressures to allow evaluation of the influences of both gas and pressure on the performance of the generator; (2) tests to determine the transient behavior of the generators; and (3) operation of the generator in conjunction with the Voyager spacecraft.

Rouklove, P.

1977-01-01

186

Measurement resolution of noise directivity patterns from acoustic flight tests  

NASA Technical Reports Server (NTRS)

The measurement resolution of noise directivity patterns from acoustic flight tests was investigated. Directivity angle resolution is affected by the data reduction parameters, the aircraft velocity and flyover altitude, and by deviations of the aircraft from the desired flight path. Equations are developed which determine bounds for the lateral and longitudinal directivity angle resolution as a function of the nominal directivity angle. The equations are applied to a flight test data base and the effects of several flight conditions and data reduction parameters on the directivity angle resolution are presented. The maximum directivity angle resolution typically occurs when the aircraft is at or near the overhead position. In general, directivity angle resolution improves with decreasing velocity, increasing altitude, increasing sampling rate, decreasing block size, and decreasing block averages. Deviations from the desired ideal flight path will increase the resolution. For the flight experiment considered in this study, an average of two flyovers were required at each test condition to obtain an acceptable flight path. The ability of the pilot to maintain the flight track improved with decreasing altitude, decreasing velocity, and practice. Due to the prevailing wind conditions, yaw angles of as much as 20 deg were required to maintain the desired flight path.

Conner, David A.

1989-01-01

187

Design of a Central Pattern Generator for Bionic-robot Joint with Angular Frequency Modulation  

Microsoft Academic Search

The paper proposes an artificial central pattern generator (CPG) for bionic-robot joint control. The neural oscillator adopted to produce rhythmic pattern is specially designed from original sin-cosine oscillator model. An amplitude neural estimator consisted of two neurons is presented to provide sensor feedback to CPG control. The artificial CPG can adapt itself to the physical system parameters variety by rhythmic

Daibing Zhang; Dewen Hu; Linchen Shen; Haibin Xie

2006-01-01

188

Evolution and Development of a Central Pattern Generator for the Swimming of a Lamprey  

Microsoft Academic Search

This article describes the design of neural control architectures for locomotion using an evolutionary approach. Inspired by the central pattern generators found in animals, we develop neural controllers that can produce the patterns of oscillations necessary for the swimming of a simulated lamprey. This work is inspired by Ekeberg's neuronal and mechanical model of a lamprey [11] and follows experiments

Auke Jan Ijspeert; Jérôme Kodjabachian

1999-01-01

189

Gas Generation Testing of Neptunium Oxide at Elevated Temperature  

SciTech Connect

Elevated temperature gas generation tests have been conducted using neptunium dioxide produced on a laboratory scale using the HB-Line Phase II flowsheet. These tests were performed to determine what effect elevated temperatures would have on the neptunium dioxide in comparison to neptunium dioxide tested at ambient temperature. The headspace gas compositions following storage at elevated temperatures associated with normal conditions of transport (NCT) have been measured. These test results show an increase in hydrogen generation rate at elevated temperature and significant removal of oxygen from the headspace gas. The elevated temperature gas generation tests described in this report involved heating small test vessels containing neptunium dioxide and measuring the headspace gas pressure and composition at the end of the test period. Four samples were used in these tests to evaluate the impact of process variables on the gas generation rate. Two samples were calcined to 600 degrees Celsius and two were calcined to 650 degrees Celsius. Each test vessel contained approximately 9.5 g of neptunium dioxide. Following exposure to 75 per cent relative humidity (RH) for five days, these samples were loaded in air and then heated to between 105 and 115 degrees Celsius for about one month. At the conclusion of the test period, the headspace gas of each container was analyzed using a micro-gas chromatograph installed in the glovebox where the experiments were conducted. The pressure, volume, and composition data for the headspace gas samples were used to calculate average H2 generation rates.

Duffey, JM

2004-01-30

190

COMPACTEST: a method to generate compact test sets for combinational circuits  

Microsoft Academic Search

Heuristics to aid the derivation of small test sets that detect single stuck-at faults in combinational logic circuits are proposed. The heuristics can be added to existing test pattern generators without compromising fault coverage. Experimental results obtained by adding the proposed heuristics to a simple PODEM procedure and applying it to the ISCAS-85 and fully-scanned ISCAS-89 benchmark circuits are presented

Irith Pomeranz; Lakshmi N. Reddy; Sudhakar M. Reddy

1993-01-01

191

Sum-discrepancy test on pseudorandom number generators  

Microsoft Academic Search

We introduce a non-empirical test on pseudorandom number generators (prng), named sum-discrepancy test. We compute the distribution of the sum of consecu- tive m outputs of a prng to be tested, under the assumption that the initial state is uniformly randomly chosen. We measure its discrepancy from the ideal distribution, and then estimate the sample size which is necessary to

Makoto Matsumoto; Takuji Nishimura

2003-01-01

192

Automated Test Program Generation for an Industrial Optimizing Compiler  

Microsoft Academic Search

This paper presents joint research and practice on automated test program generation for an industrial compiler, UniPhier, by Matsushita Electric Industrial Co., Ltd. (MEI) and Institute of Software, Chinese Academy of Sciences (ISCAS) since Sept. 2002. To meet the test requirements of MEI's engineers, we proposed an automated approach to produce test programs for UniPhier, and as a result we

Chen Zhao; Yunzhi Xue; Qiuming Tao; Liang Guo; Zhaohui Wang

2009-01-01

193

Automated Test Data Generation using Search Based Software Engineering  

Microsoft Academic Search

Generating test data is a demanding process. With- out automation, the process is slow, expensive and error- prone. However, techniques to automate test data genera- tion must cater for a bewildering variety of functional and non-functional test adequacy criteria and must either im- plicitly or explicitly solve problems involving state propa- gation and constraint satisfaction. This talk will show how

Mark Harman

2007-01-01

194

Towards a test cases generation method for Security Policies  

Microsoft Academic Search

Security Policy specification and testing constitute two fundamental challenges in the development of secure communication systems since they can ensure that a security policy is correctly enforced. Model checking techniques can be used to do such task. Given a system modeling and a test criterion, the model checker can generate a counterexample from which test cases can be deduced. To

Ryma Abbassi; S. G. El Fatmi

2009-01-01

195

Turbulence anisotropy and coherent structures in electromagnetically generated vortex patterns  

NASA Astrophysics Data System (ADS)

Numerical investigations addressing influence of the localised electromagnetic forcing on turbulent thermal convection of a weakly electrically conductive fluid in a wall-bounded rectangular enclosure are performed over a wide range of working parameters (104<=Ra<=5×105, Pr = 7). An asymmetrical electromagnetic forcing (EMF) is applied originating from combined effects of the imposed magnetic fields (originating from an array of 5×7 permanent magnets with |b0|max = 1 T each, located beneath the lower thermally active wall) and electric fields (originating from two electrodes supplied with dc current of different intensities, 0<=I<=10 A). Subgrid turbulent stress is modelled by electromagnetically extended Smagorinsky model and subgrid turbulent heat flux is represented by a simple gradient diffusion hypothesis. Simulations revealed two interesting findings: the electromagnetic forcing generated significant overall heat transfer increase (more than 500% for lower values of Ra) compared to its neutral case, and, the turbulence anisotropy was reduced in the central part of the enclosure.

Kenjereš, S.

2011-12-01

196

Analysing Humanly Generated Random Number Sequences: A Pattern-Based Approach  

PubMed Central

In a random number generation task, participants are asked to generate a random sequence of numbers, most typically the digits 1 to 9. Such number sequences are not mathematically random, and both extent and type of bias allow one to characterize the brain's “internal random number generator”. We assume that certain patterns and their variations will frequently occur in humanly generated random number sequences. Thus, we introduce a pattern-based analysis of random number sequences. Twenty healthy subjects randomly generated two sequences of 300 numbers each. Sequences were analysed to identify the patterns of numbers predominantly used by the subjects and to calculate the frequency of a specific pattern and its variations within the number sequence. This pattern analysis is based on the Damerau-Levenshtein distance, which counts the number of edit operations that are needed to convert one string into another. We built a model that predicts not only the next item in a humanly generated random number sequence based on the item?s immediate history, but also the deployment of patterns in another sequence generated by the same subject. When a history of seven items was computed, the mean correct prediction rate rose up to 27% (with an individual maximum of 46%, chance performance of 11%). Furthermore, we assumed that when predicting one subject?s sequence, predictions based on statistical information from the same subject should yield a higher success rate than predictions based on statistical information from a different subject. When provided with two sequences from the same subject and one from a different subject, an algorithm identifies the foreign sequence in up to 88% of the cases. In conclusion, the pattern-based analysis using the Levenshtein-Damarau distance is both able to predict humanly generated random number sequences and to identify person-specific information within a humanly generated random number sequence.

Schulz, Marc-Andre; Schmalbach, Barbara; Brugger, Peter; Witt, Karsten

2012-01-01

197

Analysing humanly generated random number sequences: a pattern-based approach.  

PubMed

In a random number generation task, participants are asked to generate a random sequence of numbers, most typically the digits 1 to 9. Such number sequences are not mathematically random, and both extent and type of bias allow one to characterize the brain's "internal random number generator". We assume that certain patterns and their variations will frequently occur in humanly generated random number sequences. Thus, we introduce a pattern-based analysis of random number sequences. Twenty healthy subjects randomly generated two sequences of 300 numbers each. Sequences were analysed to identify the patterns of numbers predominantly used by the subjects and to calculate the frequency of a specific pattern and its variations within the number sequence. This pattern analysis is based on the Damerau-Levenshtein distance, which counts the number of edit operations that are needed to convert one string into another. We built a model that predicts not only the next item in a humanly generated random number sequence based on the item's immediate history, but also the deployment of patterns in another sequence generated by the same subject. When a history of seven items was computed, the mean correct prediction rate rose up to 27% (with an individual maximum of 46%, chance performance of 11%). Furthermore, we assumed that when predicting one subject's sequence, predictions based on statistical information from the same subject should yield a higher success rate than predictions based on statistical information from a different subject. When provided with two sequences from the same subject and one from a different subject, an algorithm identifies the foreign sequence in up to 88% of the cases. In conclusion, the pattern-based analysis using the Levenshtein-Damarau distance is both able to predict humanly generated random number sequences and to identify person-specific information within a humanly generated random number sequence. PMID:22844490

Schulz, Marc-André; Schmalbach, Barbara; Brugger, Peter; Witt, Karsten

2012-01-01

198

Test Input Generation for Red-Black Trees using Abstraction  

NASA Technical Reports Server (NTRS)

We consider the problem of test input generation for code that manipulates complex data structures. Test inputs are sequences of method calls from the data structure interface. We describe test input generation techniques that rely on state matching to avoid generation of redundant tests. Exhaustive techniques use explicit state model checking to explore all the possible test sequences up to predefined input sizes. Lossy techniques rely on abstraction mappings to compute and store abstract versions of the concrete states; they explore under-approximations of all the possible test sequences. We have implemented the techniques on top of the Java PathFinder model checker and we evaluate them using a Java implementation of red-black trees.

Visser, Willem; Pasareanu, Corina S.; Pelanek, Radek

2005-01-01

199

Performance testing of a Transit generator at JPL.  

NASA Technical Reports Server (NTRS)

A Transit type thermoelectric generator, serial number QM-III, assembled with lightweight Isotec type thermoelectric panels, has been placed on test at the Jet Propulsion Laboratory. In its exterior appearance and main constructive features, generator QM-III is similar to the generator which was flown on the Transit satellite, launched into circular polar orbit on Sept. 2, 1972. The main difference between the flight generator and QM-III is that the flight hardware is heated by radioisotope decay, while QM-III is an ETG and is assembled with three different types of thermoelectric panels. The paper describes the generator and test equipment used and presents the results of the tests performed to date.

Rouklove, P.

1973-01-01

200

Gray scaling in high performance optical pattern generators  

NASA Astrophysics Data System (ADS)

This paper is a comparison of different gray scaling techniques used in optical mask making. It shows that high address resolution and high throughput can be combined with the lithographic performance necessary for the most advanced applications. In the semiconductor industry, Moore's law continues to describe the ever-increasing demand for better performance in terms of clock-frequency and circuit density. One effect is shrinking design grids to cope with the tighter requirements on resolution, CD control, and aggressive OPC. For mask making this means that the address resolution of the mask writing equipment must be improved for every tool generation. The address resolution in the mask writer can be increased in two ways; either by decreasing the physical grid, or by introducing a virtual grid by using gray scaling. In the former case, the throughput, a performance parameter of utmost importance for reasonable mask costs and cycle times, will suffer a high penalty. In the latter case, however, a fine address grid is created, while keeping a large physical grid for high throughput. In earlier publications, a single pass raster scan gray scaling technique has been shown to reduce image quality in terms of image log-slope. This paper shows that the effects are kept to a minimum in the SLM-based DUV Sigma7300 mask writer, which uses partial coherent imaging and multiple writing passes. Analysis shows that the reduction in image log-slope due to gray scaling is less than 8%. In addition, the systematic averaging of four displaced writing passes makes the loss isotropic and independent of grid position. A detailed error analysis shows that a small address grid is more important for composite CD uniformity than the loss in image log-slope.

Martinsson, Hans; Sandstrom, Tor

2005-11-01

201

Hemispatial PCA dissociates temporal from parietal ERP generator patterns  

PubMed Central

Event-related potentials (31-channel ERPs) were recorded from 38 depressed, unmedicated outpatients and 26 healthy adults (all right-handed) in tonal and phonetic oddball tasks developed to exploit the perceptual challenge of a dichotic stimulation. Tonal nontargets were pairs of complex tones (corresponding to musical notes G and B above middle C) presented simultaneously to each ear (L/R) in an alternating series (G/B or B/G; 2-s fixed SOA). A target tone (note A) replaced one of the pair on 20% of the trials (A/B, G/A, B/A, A/G). Phonetic nontargets were L/R pairs of syllables (/ba/, /da/) with a short voice onset time (VOT), and targets contained a syllable (/ta/) with a long VOT. Subjects responded with a left or right button press to targets (counterbalanced across blocks). Target detection was poorer in patients than controls and for tones than syllables. Reference-free current source densities (CSDs; spherical spline Laplacian) derived from ERP waveforms were simplified and measured using temporal, covariance-based PCA followed by unrestricted Varimax rotation. Target-related N2 sinks and mid-parietal P3 sources were represented by CSD factors peaking at 245 and 440 ms. The P3 source topography included a secondary, left-lateralized temporal lobe maximum for both targets and nontargets. However, a subsequent hemispheric spatiotemporal PCA disentangled temporal lobe N1 and P3 sources as distinct factors. P3 sources were reduced in patients compared with controls, even after using performance as a covariate. Results are consistent with prior reports of P3 reduction in depression and implicate distinct parietal and temporal generators of P3 when using a dichotic oddball paradigm.

Tenke, Craig E.; Kayser, Jurgen; Shankman, Stewart A.; Griggs, Carlye B.; Leite, Paul; Stewart, Jonathan W.; Bruder, Gerard E.

2008-01-01

202

Online trajectory generation in an amphibious snake robot using a lamprey-like central pattern generator model  

Microsoft Academic Search

This article presents a control architecture for controlling the locomotion of an amphibious snake\\/lamprey robot capable of swimming and serpentine locomotion. The control architecture is based on a central pattern generator (CPG) model inspired from the neural circuits controlling locomotion in the lamprey's spinal cord. The CPG model is implemented as a system of coupled nonlinear oscillators on board of

Auke Jan Ijspeert; Alessandro Crespi

2007-01-01

203

Automated Test Data Generation Based on Program Execution  

Microsoft Academic Search

Software test is a very important phase in software development, and an important means to ensure the software's reliability. Path-oriented testing is a main approach in software test. In this paper, an automated test data generation method for linear approximation of bifurcation function is proposed. Combined with predicate slice and definition-use-control (DUG) expression of function, an innovative algorithm for path-oriented

Jun-yi Li; Jia-guang Sun; Ying-ping Lu

2006-01-01

204

Feedback-Based Coverage Directed Test Generation: An Industrial Evaluation  

NASA Astrophysics Data System (ADS)

Although there are quite a few approaches to Coverage Directed test Generation aided by Machine Learning which have been applied successfully to small and medium size digital designs, it is not clear how they would scale on more elaborate industrial-level designs. This paper evaluates one of these techniques, called MicroGP, on a fully fledged industrial design. The results indicate relative success evidenced by a good level of code coverage achieved with reasonably compact tests when compared to traditional test generation approaches. However, there is scope for improvement especially with respect to the diversity of the tests evolved.

Ioannides, Charalambos; Barrett, Geoff; Eder, Kerstin

205

Flow patterns generated by oblate medusan jellyfish: field measurements and laboratory analyses  

Microsoft Academic Search

Flow patterns generated by medusan swimmers such as jellyfish are known to differ according the morphology of the various animal species. Oblate medusae have been previously observed to generate vortex ring structures during the propulsive cycle. Owing to the inherent physical coupling between locomotor and feeding structures in these animals, the dynamics of vortex ring formation must be robustly tuned

John O. Dabiri; Sean P. Colin; John H. Costello; Morteza Gharib

2005-01-01

206

Abstraction Based Automated Test Generation from Formal Tabular Requirements Specifications  

Microsoft Academic Search

\\u000a We propose an automated approach for generating tests from formal tabular requirements specifications, such as SCR specifications.\\u000a The technique is based on counterexample guided abstraction refinement and the use of SMT solving. Moreover, in order to effectively\\u000a perform automated test generation, we take advantage of particular characteristics of tabular requirements descriptions to\\u000a aid the abstraction and abstraction refinement processes. The

Renzo Degiovanni; Pablo Ponzio; Nazareno Aguirre; Marcelo Frias

207

Automatic Generation of Floating-Point Test Data  

Microsoft Academic Search

For numerical programs, or more generally for programs with floating-point data, it may be that large savings of time and storage are made possible by using numerical maximization methods instead of symbolic execution to generate test data. Two examples, a matrix factorization subroutine and a sorting method, illustrate the types of data generation problems that can be successfully treated with

Webb Miller; David L. Spooner

1976-01-01

208

Using Model Checking to Generate Tests from Specifications  

Microsoft Academic Search

We apply a model checker to the problem of test generation using a new application of mutation analysis. We define syntactic operators, each of which produces a slight variation on a given model. The operators define a form of mutation analysis at the level of the model checker specification. A model checker generates counterexamples which distinguish the variations from the

Paul Ammann; Paul E. Black; William Majurski

1998-01-01

209

Flexibility of Motor Pattern Generation Across Stimulation Conditions by the Neonatal Rat Spinal Cord  

PubMed Central

Previous studies have demonstrated that “locomotor-like” rhythmic patterns can be evoked in the isolated neonatal rat spinal cord by several means, including pharmacological neuromodulation and electrical stimulation of various pathways. Recent studies have used stimulation of afferent pathways to evoke rhythmic patterns, relying on synaptic activation of interneuronal systems rather than global imposition of neuromodulatory state by pharmacological agents. We use the in vitro neonatal rat spinal cord with attached hindlimb to examine the muscle activation patterns evoked by stimulation of these different pathways and evaluate whether stimulation of these pathways all evoke the same patterns. We find that the patterns evoked by bath application of serotonin (5-HT) and N-methyl-d-aspartic acid (NMDA) consisted of alternation between hip flexors and extensors and similar alternation was observed in the patterns evoked by electrical stimulation of the cauda equina (CE) or contralateral fifth lumbar (L5) dorsal nerve root. In contrast, the knee extensor/hip flexor rectus femoris (RF) and knee flexor/hip extensor semitendinosus (ST) were activated differentially across stimulation conditions. In 5-HT/NMDA patterns, RF was active in late flexion and ST in late extension. In CE patterns, these two muscles switched places with RF typically active in late extension and ST active in flexion. In L5 patterns, ST was activated in extension and RF was silent or weakly active during flexion. There were also systematic differences in the consistency of rhythms evoked by each stimulation method: patterns evoked by electrical stimulation of CE or L5 were less consistently modulated with the rhythm when compared with 5-HT/NMDA-evoked patterns. All differences were preserved following deafferentation, demonstrating that they reflect intrinsic properties of spinal systems. These results highlight the intrinsic flexibility of motor pattern generation by spinal motor circuitry which is present from birth and provides important information to many studies examining spinal pattern generating networks.

Klein, David A.; Patino, Angelica

2010-01-01

210

Automatic Generation of English-Japanese Translation Pattern Utilizing Genetic Programming Technique  

NASA Astrophysics Data System (ADS)

There are a lot of constructional differences in an English-Japanese phrase template, and that often makes the act of translation difficult. Moreover, there exist various and tremendous phrase templates and sentence to be refered to. It is not easy to prepare the corpus that covers the all. Therefore, it is very significant to generate the translation pattern of the sentence pattern automatically from a viewpoint of the translation success rate and the capacity of the pattern dictionary. Then, for the purpose of realizing the automatic generation of the translation pattern, this paper proposed the new method for the generation of the translation pattern by using the genetic programming technique (GP). The technique tries to generate the translation pattern of various sentences which are not registered in the phrase template dictionary automatically by giving the genetic operation to the parsing tree of a basic pattern. The tree consists of the pair of the English-Japanese sentence generated as the first stage population. The analysis tree data base with 50,100,150,200 pairs was prepared as the first stage population. And this system was applied and executed for an English input of 1,555 sentences. As a result, the analysis tree increases from 200 to 517, and the accuracy rate of the translation pattern has improved from 42.57% to 70.10%. And, 86.71% of the generated translations was successfully done, whose meanings are enough acceptable and understandable. It seemed that this proposal technique became a clue to raise the translation success rate, and to find the possibility of the reduction of the analysis tree data base.

Matsumura, Koki; Tamekuni, Yuji; Kimura, Shuhei

211

An Approach for Semi-Automated Test Generation and Test Maintenance Student  

Microsoft Academic Search

As unit testing has evolved to an established practice in software development, writing and maintaining tests on acceptance level still causes a major effort. This work presents a concept for an integrated testing tool which provides the developer with an automated test generation and maintenance tool. This relieves the developer from manually writing and updating test code which helps to

Wolfgang Pree; Martin Kropp

2009-01-01

212

Automated test data generation for aspect-oriented programs  

Microsoft Academic Search

Despite the upsurge of interest in the Aspect-Oriented Program- ming (AOP) paradigm, there remain few results on test data gener- ation techniques for AOP. Furthermore, there is no work on search- based optimization for test data generation, an approach that has been shown to be successful in other programming paradigms. In this paper, we introduce a search-based optimization approach to

Mark Harman; Fayezin Islam; Tao Xie; Stefan Wappler

2009-01-01

213

Test Generation from LOTOS Specifications with Data-Value Communication.  

National Technical Information Service (NTIS)

The problem of generating tests from LOTOS specifications is discussed. An existing algorithm is extended to cover data transfer and processing aspects of LOTOS. The new algorithm and a tool implementing it are based on the idea of producing abstract test...

J. Arkko

1991-01-01

214

NASA Fastrac Engine Gas Generator Component Test Program and Results.  

National Technical Information Service (NTIS)

This presentation consists of viewgraph which review the test program and the results of the tests for the Gas Generator (GG) component for the Fastrac Engine. Included are pictures of the Fastrac (MC-1) Engine and the GG, diagrams of the flight configura...

H. J. Dennis T. Sanders

2000-01-01

215

Automated Test Data Generation Algorithm Based on Reversed Binary Tree  

Microsoft Academic Search

Automated test data generation technology is a hot researching area in automated software test. Some kinds of new concepts such as base node, control node, definition node and definition related control node set are proposed, and in addition, a solution to obtain the definition related control node set is designed, on the basis of combining both the method of linear

Jun-Yi Li; Jia-Guang Sun

2007-01-01

216

Computational method for testing computer-generated holograms  

Microsoft Academic Search

A procedure based entirely on computer simulation is developed for testing the quality of computer-generated holographic optical elements (CGHOEs). This new testing method may be of help in optimization techniques in the future. We introduce a mathematical quantity, the correlation, to characterize the performance of the studied CGHOE. Our procedure examines how the correlation between the object and the reconstructed

Nandor Bokor; Zsolt Papp

1996-01-01

217

Performance results of a digital test signal generator  

NASA Technical Reports Server (NTRS)

Performance results of a digital test signal-generator hardware-demonstration unit are reported. Capabilities available include baseband and intermediate frequency (IF) spectrum generation, for which test results are provided. Repeatability in the setting of a given signal-to-noise ratio (SNR) when a baseband or an IF spectrum is being generated ranges from 0.01 dB at high SNR's or high data rates to 0.3 dB at low data rates or low SNR's. Baseband symbol SNR and carrier SNR (Pc/No) accuracies of 0.1 dB were verified with the built-in statistics circuitry. At low SNR's that accuracy remains to be fully verified. These results were confirmed with measurements from a demodulator synchronizer assembly for the baseband spectrum generation, and with a digital receiver (Pioneer 10 receiver) for the IF spectrum generation.

Gutierrez-Luaces, B. O.; Marina, M.; Parham, B.

1993-01-01

218

Evaluation of Auto-Test Generation Strategies and Platforms  

NASA Astrophysics Data System (ADS)

As the test effort takes a significant part of the software development lifecycle, efficient test strategies are a precondition for reduction of development costs and time. In this respect two main issues exist: firstly, the tuning of the test track from test case identification to evaluation, secondly, the reduction of number of test cases to be processed and evaluated. Both aspects were considered in the work presented in this paper. For reduction of the effort related to the test track two test automation tools have been applied: DCRTT for C and SmartG for Java. While DCRTT is ready for industrial use at high degree of automation of all test steps, SmartG is a prototype exploiting the identifcation of path sets by random testing. DCRTT only requires provision of the source files and then delivers test drivers, a filtered and reduced set of test cases, related test results and detailed information on data ranges and observed exceptions. The manual effort is reduced to test evaluation. DCRTT identifies a significantly reduced set of test cases left for manual evaluation. The selection criteria are based on block coverage, decision coverage and occurrence of exceptions when generating inputs from the valid and invalid data range. One or more test cases may be collected for each basket of such a criterion and element of a function's structure. It is of high importance how well such automated strategies do work. Therefore a number of investigations have been performed, evaluating the achieved coverage and number of reported exceptions. Three test modes have been considered: random and lattice-based test generation for module testing and operational testing imposing the complete main program to representative operational conditions.

Gerlich, R.; Gerlich, R.; Boll, T.; Mayer, J.

2007-08-01

219

Real time motion generation and control for biped robot -2nd report: Running gait pattern generation  

Microsoft Academic Search

Bipedal running can easily result in a fall due to poor availability of the ground reaction force at the boundary of the flight and support phases. We propose methods to decompose and synthesize a running gait pattern into vertical, horizontal and rotational components so that time-dependent ground friction limits are satisfied. We also extend previously proposed boundary condition, the divergent

Toru Takenaka; Takashi Matsumoto; Takahide Yoshiike; Shinya Shirokura

2009-01-01

220

Molten carbonate fuel cell power generation system test facility  

NASA Astrophysics Data System (ADS)

CRIEPI has installed the Molten Carbonate Fuel Cell (MCFC) Power Generation System Test Facility which can be used for the tests of the MCFC subsystem. The purpose of this facility installation are as follows: (1) to clarify the large stack performance and to evaluate the large stack durability; and (2) to develop the operation technology of the MCFC which is installed within the system. The facility is divided into two sections, the single loop and the recycle loop. Before power generation tests using MCFC stacks, CRIEPI checked the performance of the facility and ensured that the two loops have the preferable performance.

Watanabe, Takao; Izaki, Yoshiyuki; Hayasaka, Takao; Horiuchi, Nagayuki; Hamamatsu, Teruo; Ishikawa, Hiroshi

1989-05-01

221

Integration and optimization of the DUV ALTA pattern generation system using a CAR process with the Tetra photomask etch system  

NASA Astrophysics Data System (ADS)

Etec Systems, the Mask Business Group of Applied Materials, is in a unique position within the mask making industry - Etec has the opportunity to integrate individual parts of the overall mask manufacturing process to provide a more complete solution. Here we present the integration of the DUV ALTA laser pattern generator and the TetraTM photomask etch system with advanced CAR resist processes. Dry etch process effects of flow, overetch, and oxygen content (in a Cl2/O2/He plasma) are discussed for the baseline POR resist in terms of etch rate, selectivity, etch bias, CD uniformity and micro-loading; the optimized etch process space was then implemented for advanced CAR resists. Iso-dense bias, football pattern loading and other pattern transfer results influencing mask manufactureability are also presented. Within the synthesis and optimization of the pattern generation system, process, and dry etch sub 13 nm range process uniformity has been achieved. The integrated ALTA / Tetra / Advanced-CAR solution set is characterized on both Etec test patterns and customer demonstrations.

Buxbaum, Alex H.; Fuller, Scott E.; Montgomery, Warren; Ungureit, Michael E.

2003-12-01

222

Generation of Electrically Induced Stimuli for MEMS Self-Test  

Microsoft Academic Search

A major task for the implementation of Built-In-Self-Test (BIST) strategies for MEMS is the generation of the test stimuli. These devices can work in different energy domains and are thus designed to sense signals which are generally not electrical. In this work, we describe, for different types of MEMS, how the required non-electrical test stimuli can be induced on-chip by

Benoît Charlot; Salvador Mir; Fabien Parrain; Bernard Courtois

2001-01-01

223

Automated Test Generation for AspectJ Programs  

Microsoft Academic Search

Aspect-oriented software development (AOSD) is a new paradigm that improves separation of concerns in software development. AOSD has gained popularity with the adoption of languages such as As- pectJ. Automated test generation for AspectJ programs is important for reducing the manual effort in testing AspectJ programs. This position paper proposes Wrasp, a framework for automatic gener- ation of tests for

Tao Xie; Jianjun Zhao; Darko Marinov; David Notkin

224

Experimentally derived model for the locomotor pattern generator in the Xenopus embryo.  

PubMed Central

1. Simulations of Xenopus embryo spinal neurons were endowed with Hodgkin-Huxley-style models of voltage-dependent Na+, Ca2+, slow K+ and fast K+ currents together with a Na(+)-dependent K+ current. The parameters describing the activation, inactivation and relaxation of these currents were derived from previous voltage-clamp studies of Xenopus embryo spinal neurons. Each of the currents was present at realistic densities. 2. The model neurons fired repetitively in response to current injection. The Ca2+ current was essential for repetitive firing in response to current injection. The fast K+ current appeared mainly to control spike width, whereas the slow K+ current exerted a powerful influence on the reptitive firing properties of the neurons without markedly affecting spike width. 3. The properties of the model neurons could be made more consistent with those previously reported for Xenopus embryo neurons during intracellular recordings in vivo, if the shunting effect of the sharp microelectrode was incorporated into the model. 4. The model neurons were then used to create a simplified version of the spinal network that controls swimming in the frog embryo. This model network could generate the motor pattern for swimming: the activity between the left and right sides alternated with a cycle period that varied from 50 to 120 ms. This is very similar to the range of cycle periods observed in the real embryo. The shunting effect of the microelectrode was once again taken into account. 5. Reductions of the K+ currents perturbed the motor pattern and gave three forms of aberrant motor activity very similar to those previously seen during the application of K+ channel blockers to the real embryo. The ability to generate the correct motor pattern for swimming in the model depended on the balance between the K+ currents and the inward Na+ and Ca2+ currents rather than their absolute values. 6. The model network could generate a motor pattern for swimming over a very wide range of excitatory (2-10 nS) and inhibitory (2-400 nS) synaptic strengths. Rough estimates of the physiological synaptic strengths in the real circuit (around 20-60 nS for inhibition and 2-5 nS for excitation) fall within the range of synaptic strengths that gave simulation of the swimming motor pattern in the model. 7. The cycle period of the motor activity in the model shortened either as the excitatory synapses were strengthened or as the inhibitory synapses were weakened. 8. The prediction that the strength of the mid-cycle inhibition determines cycle period has been tested by using low levels of strychnine to reduce glycinergic reciprocal inhibition in a graded manner in the real embryo. As the inhibition was reduced, the cycle period of fictive swimming in the embryo shortened by amounts very close to those predicted by the model. 9. This new experimentally derived model can replicate many of the known features of fictive swimming in the real embryo and may be of value as an analytical tool in attempting to understand how the spinal circuitry of the Xenopus embryo and related amphibian embryos control a variety of motor behaviours. Images Figure 4 Figure 11

Dale, N

1995-01-01

225

Conformance Testing with Labelled Transition Systems: Implementation Relations and Test Generation  

Microsoft Academic Search

This paper studies testing based on labelled transition systems, presenting two test generation algorithms with their corresponding implementation relations. The first algorithm assumes that implementations communicate with their environment via symmetric, synchronous interactions. It is based on the theory of testing equivalence and preorder, as is most of the testing theory for labelled transition systems, and it is found in

Jan Tretmans

1996-01-01

226

Response of Steam and Hydroelectric Generating Plants to Generation Control Tests  

Microsoft Academic Search

This paper presents some of the control characteristics of generating plants as determined by field measurement. Tests on generating units in service have determined that governor dead band varies widely between governors and between load points for some governors. Large new steam turbines have been found with governors having dead bands so large that the governor seldom caused the unit

A. Klopfenstein

1959-01-01

227

Postembryonic development of centrally generated flight motor patterns in the hawkmoth, Manduca sexta.  

PubMed

This study analyses the maturation of centrally generated flight motor patterns during metamorphosis of Manduca sexta. Bath application of the octopamine agonist chlordimeform to the isolated central nervous system of adult moths reliably induces fictive flight patterns in wing depressor and elevator motoneurons. Pattern maturation is investigated by chlordimeform application at different developmental stages. Chlordimeform also induces motor patterns in larval ganglia, which differ from fictive flight, indicating that in larvae and adults, octopamine affects different networks. First changes in motoneuron activity occur at the pupal stage P10. Rhythmic motor output is induced in depressor, but not in elevator motoneurons at P12. Adult-like fictive flight activity in motoneurons is observed at P16 and increases in speed and precision until emergence 2 days later. Pharmacological block of chloride channels with picrotoxin also induces fictive flight in adults, suggesting that the pattern-generating network can be activated by the removal of inhibition, and that proper network function does not rely on GABA(A) receptors. Our results suggest that the flight pattern-generating network becomes gradually established between P12 and P16, and is further refined until adulthood. These findings are discussed in the context of known physiological and structural CNS development during Manduca metamorphosis. PMID:19924416

Vierk, Ricardo; Duch, Carsten; Pflüger, Hans-Joachim

2010-01-01

228

Generative Models of Segregation: Investigating Model-Generated Patterns of Residential Segregation by Ethnicity and Socioeconomic Status  

PubMed Central

This paper considers the potential for using agent models to explore theories of residential segregation in urban areas. Results of generative experiments conducted using an agent-based simulation of segregation dynamics document that varying a small number of model parameters representing constructs from urban-ecological theories of segregation can generate a wide range of qualitatively distinct and substantively interesting segregation patterns. The results suggest how complex, macro-level patterns of residential segregation can arise from a small set of simple micro-level social dynamics operating within particular urban-demographic contexts. The promise and current limitations of agent simulation studies are noted and optimism is expressed regarding the potential for such studies to engage and contribute to the broader research literature on residential segregation.

Fossett, Mark

2011-01-01

229

Focal High Cell Density Generates a Gradient of Patterns in Self-Organizing Vascular Mesenchymal Cells  

PubMed Central

In embryogenesis, structural patterns, such as vascular branching, may form via a reaction-diffusion mechanism in which activator and inhibitor morphogens guide cells into periodic aggregates. We previously found that vascular mesenchymal cells (VMC) spontaneously aggregate into nodular structures and that morphogen pairs regulate the aggregation into patterns of spots and stripes. To test the effect of a focal change in activator morphogen on VMC pattern formation, we created a focal zone of high cell density by plating a second layer VMC within a cloning ring over a confluent monolayer. After 24 hours, the ring was removed, and pattern formation monitored by phase-contrast microscopy. At days 2–8, the patterns progressed from uniform distributions to swirl, labyrinthine, and spot patterns. Within the focal high-density zone and a narrow halo zone, cells aggregated into spot patterns; in the outermost zone of the plate, cells formed a labyrinthine pattern. Area occupied by aggregates was significantly greater in the outermost zone than in the HDZ or halo. The rate of pattern progression within the HDZ increased as a function of its plating density. Thus, focal differences in cell density may drive pattern formation gradients in tissue architecture, such as vascular branching.

Cheng, Henry; Reddy, Aneela; Sage, Andrew; Lu, Jinxiu; Garfinkel, Alan; Tintut, Yin; Demer, Linda

2012-01-01

230

A Pattern Generator of Humanoid Robots Walking on a Rough Terrain  

Microsoft Academic Search

Abstract—This paper presents a motion,pattern generator,of humanoid robots that walks on a flat plane, steps and a rough terrain. It is guaranteed,rigorously,that the desired,contact between,a humanoid,robot and,terrain should,be maintained by keeping,the contact wrench sum between them inside the contact wrench,cone under,the sufficient friction assumption. A walking,pattern is generated,by solving the contact wrench equations,and,by applying,the resolved momentum,control.

Hirohisa Hirukawa; Shizuko Hattori; Shuuji Kajita; Kensuke Harada; Kenji Kaneko; Fumio Kanehiro; Mitsuharu Morisawa; Shinichiro Nakaoka

2007-01-01

231

Micromachining of amplitude and phase modulated reflective computer generated hologram patterns in silicon  

NASA Astrophysics Data System (ADS)

Silicon has been machined on lateral resolutions of micrometers and on depth resolutions of nanometers using a recently-developed process based on ion irradiation and electrochemical anodisation. Here we investigate its use as a recording medium for computer generated hologram patterns. We describe the fabrication of both amplitude and phase binary modulated reflective computer generated hologram patterns on a silicon surface with pixel sizes of 5 ?m. We further discuss the use of micromachined silicon to variably modulate both amplitude and phase in a continuous, rather than a binary fashion.

Ow, Y. S.; Breese, M. B. H.; Leng, Y. R.; Azimi, S.; Teo, E. J.; Sun, X. W.

2010-05-01

232

One-eighth look-up table method for effectively generating computer-generated hologram patterns  

NASA Astrophysics Data System (ADS)

To generate ideal digital holograms, a computer-generated hologram (CGH) has been regarded as a solution. However, it has an unavoidable problem in that the computational burden for generating CGH is very large. Recently, many studies have been conducted to investigate different solutions in order to reduce the computational complexity of CGH by using particular methods such as look-up tables (LUTs) and parallel processing. Each method has a positive effectiveness about reducing computational time for generating CGH. However, it appears to be difficult to apply both methods simultaneously because of heavy memory consumption of the LUT technique. Therefore, we proposed a one-eighth LUT method where the memory usage of the LUT is reduced, making it possible to simultaneously apply both of the fast computing methods for the computation of CGH. With the one-eighth LUT method, only one-eighth of the zone plates were stored in the LUT. All of the zone plates were accessed by indexing method. Through this method, we significantly reduced memory usage of LUT. Also, we confirmed the feasibility of reducing the computational time of the CGH by using general-purpose graphic processing units while reducing the memory usage.

Cho, Sungjin; Ju, Byeong-Kwon; Kim, Nam-Young; Park, Min-Chul

2014-05-01

233

VIP-an input pattern generator for identifying critical voltage drop for deep sub-micron designs  

Microsoft Academic Search

We present a novel input pattern generator for dynamic power network simulation. The obtained patterns successfully identify critical voltage drop areas for a set of industrial designs, which are difficult to be found using functional vectors. The search engine of the pattern generator for worst-case IR voltage drop is based on the multiobjective genetic algorithm. To achieve high coverage for

Yin-Min Jiang; Tak K. Young; Kwang-Ting Cheng

1999-01-01

234

NASA Fastrac Engine Gas Generator Component Test Program and Results  

NASA Technical Reports Server (NTRS)

This presentation consists of viewgraph which review the test program and the results of the tests for the Gas Generator (GG) component for the Fastrac Engine. Included are pictures of the Fastrac (MC-1) Engine and the GG, diagrams of the flight configuration, and schematics of the LOX, and the RP-1 systems and the injector assembly. The normal operating parameters are reviewed, as are the test instrumentation. Also shown are graphs of the hot gas temperature, and the test temperature profiles. The results are summarized.

Dennis, Henry J., Jr.; Sanders, Tim; Turner, James E. (Technical Monitor)

2000-01-01

235

Prototype steam generator test at SCTI/ETEC. Acoustic program test plan. [LMFBR  

SciTech Connect

This document is an integrated test plan covering programs at General Electric (ARSD), Rockwell International (RI) and Argonne National Laboratory (CT). It provides an overview of the acoustic leak detection test program which will be completed in conjunction with the prototype LMFBR steam generator at the Energy Technology Engineering Laboratory. The steam generator is installed in the Sodium Components Test Installation (SCTI). Two acoustic detection systems will be used during the test program, a low frequency system developed by GE-ARSD (GAAD system) and a high frequency system developed by RI-AI (HALD system). These systems will be used to acquire data on background noise during the thermal-hydraulic test program. Injection devices were installed during fabrication of the prototype steam generator to provide localized noise sources in the active region of the tube bundle. These injectors will be operated during the steam generator test program, and it will be shown that they are detected by the acoustic systems.

Greene, D.A.; Thiele, A.; Claytor, T.N.

1981-10-01

236

Extensions to the sparse matrix technique for automatic test generation  

SciTech Connect

This paper presents additional insight into the modeling of digital systems using a sparse matrix formulation. The set of primitives used in the original formulation of the matrix model is expanded to include CMOS transmission-gate configurations. The matrix model can be used to generate tests using the path sensitization approach. A covering approach for path selection and the use of testability measures in guiding test generation are discussed. A data structure for storing the sparse matrix to perform path sensitization is suggested. Two nonclassical approaches to ATG are proposed as research items.

Acken, C.F.

1983-01-01

237

Generating Reduced Tests for FSMs with Extra States  

NASA Astrophysics Data System (ADS)

We address the problem of generating tests from a deterministic Finite State Machine to provide full fault coverage even if the faults may introduce extra states in the implementations. It is well-known that such tests should include the sequences in the so-called traversal set, which contains all sequences of length defined by the number of extra states. Therefore, the only apparent opportunity to produce shorter tests is to find within a test suite a suitable arrangement of the sequences in the inescapable traversal set. We observe that the direct concatenation of the traversal set to a given state cover, suggested by all existing generation methods with full fault coverage, results in extensive test branching, when a test has to be repeatedly executed to apply all the sequences of the traversal set. In this paper, we state conditions which allow distributing these sequences over several tests. We then utilize these conditions to elaborate a method, called SPY-method, which shortens tests by avoiding test branching as much as possible. We present the results of the experimental comparison of the proposed method with an existing method which indicate that the resulting save can be up to 40%.

Simão, Adenilso; Petrenko, Alexandre; Yevtushenko, Nina

238

A systematic approach for extracting verification patterns from an OPC test mask  

NASA Astrophysics Data System (ADS)

Optical Proximity Correction (OPC) is a crucial step in Semiconductor manufacturing for technology of dimensions below the exposure wavelength. Light from the exposure source is diffracted when passing through mask dimensions below the exposure wavelength causing patterns on wafer to differ from the intent patterns. During OPC the design intent layout patterns are modified to compensate for light diffractions so that the final wafer patterns match the design intent patterns. OPC achieves this by using OPC models that model the optical conditions, resist, and etch behavior; and an OPC recipe that controls the patterns modification process. The OPC models are calibrated from test mask structures that are developed, exposed and measured when starting to set up the manufacturing process. Structures chosen to be placed on the test mask have a great impact on the capability to predict future layout patterns that were not present in the original test mask, referred to as model coverage. Test masks are usually composed of patterns used in model calibration and others used for verifying the calibrated model. In advanced technology nodes, both the feature size and the error budget are being shrunk. Hence to reach the best model coverage with acceptable accuracy, we need to ensure that the test mask contains all the possible structures in the real designs, while maintaining that the number of patterns does not consume long metrology tools time, cause extra overhead cost to the process, or delay the development cycle. This paper presents a systematic approach to optimize the number of patterns to be included in the test mask and split test patterns into calibration and verification patterns. Results from using the proposed method are compared to other methods of splitting that are based either on geometrical or random methods. The approach provided a significant reduction in model calibration time, the number of needed patterns in the test mask, and the total development process turn-around time; while maintaining the same accuracy that can be achieved from the original test patterns set.

Kamel, Mohammad K. A.; Al-Imam, Mohamed

2012-06-01

239

Experiments with Test Case Generation and Runtime Analysis  

NASA Technical Reports Server (NTRS)

Software testing is typically an ad hoc process where human testers manually write many test inputs and expected test results, perhaps automating their execution in a regression suite. This process is cumbersome and costly. This paper reports preliminary results on an approach to further automate this process. The approach consists of combining automated test case generation based on systematically exploring the program's input domain, with runtime analysis, where execution traces are monitored and verified against temporal logic specifications, or analyzed using advanced algorithms for detecting concurrency errors such as data races and deadlocks. The approach suggests to generate specifications dynamically per input instance rather than statically once-and-for-all. The paper describes experiments with variants of this approach in the context of two examples, a planetary rover controller and a space craft fault protection system.

Artho, Cyrille; Drusinsky, Doron; Goldberg, Allen; Havelund, Klaus; Lowry, Mike; Pasareanu, Corina; Rosu, Grigore; Visser, Willem; Koga, Dennis (Technical Monitor)

2003-01-01

240

Solar Stirling power generation - Systems analysis and preliminary tests  

Microsoft Academic Search

The feasibility of an electric power generation system utilizing a sun-tracking parabolic concentrator and a Stirling engine\\/linear alternator is being evaluated. Performance predictions and cost analysis of a proposed large distributed system are discussed. Design details and preliminary test results are presented for a 9.5 ft diameter parabolic dish at the Jet Propulsion Laboratory (Caltech) Table Mountain Test Facility. Low

M. K. Selcuk; Y.-C. Wu; P. I. Moynihan; F. D. Day III

1977-01-01

241

Benzene Generation Testing for Tank 48H Waste Disposition  

SciTech Connect

In support for the Aggregation option1, researchers performed a series of tests using actual Tank 48H slurries. The tests were designed to examine potential benzene generation issues if the Tank 48H slurry is disposed to Saltstone. Personnel used the archived Tank 48H sample (HTF-E-03-127, collected September 17, 2003) for the experiments. The tests included a series of three experiments (Tests A, B, and F) performed in duplicate, giving a total of six experiments. Test A used Tank 48H slurry mixed with {approx}20:1 with Defense Waste Processing Facility (DWPF) Recycle from Tanks 21H and 22H. Test B used Tank 48H slurry mixed with {approx}2.7:1 with DWPF Recycle from Tanks 21H and 22H, while Test F used Tank 48H slurry as-is. Tests A and B occurred at 45 C, while Test F occurred at 55 C. Over a period of 8 weeks, personnel collected samples for analysis, once per week. Each sample was tested with the in-cell gamma counter. The researchers noted a decline in the cesium activity in solution which is attributed to temperature dependence of the complex slurry equilibrium. Selected samples were sent to ADS for potassium, boron, and cesium analysis. The benzene generation rate was inferred from the TPB destruction which is indirectly measured by the in-growth of cesium, potassium or boron. The results of all the analyses reveal no discernible in-growth of radiocesium, potassium or boron, indicating no significant tetraphenylborate (TPB) decomposition in any of the experiments. From boron measurements, the inferred rate of TPB destruction remained less than 0.332 mg/(L-h) implying a maximum benzene generation rate of <0.325 mg/(L-h).

Peters, T

2005-05-13

242

Steam generator tube integrity program leak rate tests. Progress report  

SciTech Connect

This interim report presents preliminary results on leak rate tests performed on through-wall defected Inconel 600 steam generator tubing. Tube defects included an EDM (electro-discharge machine) notch and IGSCC (intergranular stress corrosion cracks) of various lengths. Tests were conducted at PWR operating temperatures with leakage of hot water/steam into air. A number of IGSCC cracks were unstable under the experiment conditions of these initial tests, continuing to grow until system capacity limitations resulted in decreased pressure differential. However, initial tesing also pointed to a need for reconfiguration of the test apparatus to sustain increased flow and, more importantly, alter the mode of control. The initial test configuration is based on flow control, with pressure differential across the specimen an independent variable. This often results in pressure increases too rapid to establish the initiation of crack instability. A reconfigured system based on pressure control with flow as an independent parameter is being recommended for future tests.

Clark, R.A.; Bickford, R.L.

1984-01-01

243

Pattern-generating travelling waves in a discrete multicellular system with lateral inhibition  

NASA Astrophysics Data System (ADS)

On a one-dimensional string of cells, the juxtacrine signalling model for Delta-Notch lateral inhibition by Collier et al. [J.R. Collier, N.A.M. Monk, P.K. Maini, J.H. Lewis, Pattern formation by lateral inhibition with feedback: A mathematical model of Delta-Notch intercellular interaction, J. Theoret. Biol. 183 (1996) 429-446] exhibits a predominant alternating pattern of cells expressing either Delta or Notch, as well as many aperiodic patterns. Despite this multistationarity, in the idealised situation of no noise, travelling waves invading the unstable, homogeneous state only generate the predominant alternating pattern in their wake all over the lattice. However, this robustness is totally lost in the presence of stochastic noise because the invaded, initial state is unstable. Using linear approximations around the initial, homogeneous state and around the final, patterned state, we are able to derive analytically all essential properties of the wave: the shape of the wave front, the unique, alternating pattern generated by the wave, and the asymptotic speed of the wave front. We show that the asymptotic wave speed equals the theoretical minimum wave speed. The latter agrees extremely well with the value estimated from numerical simulations. Thus, in this system travelling waves are pulled by the leading edge of the front.

Plahte, Erik; Øyehaug, Leiv

2007-02-01

244

Diffractive elements for generating microscale laser beam patterns: a Y2K problem  

NASA Astrophysics Data System (ADS)

Lasers are widely used in industrial fabrication for engraving, cutting and many other purposes. However, material processing at very small scales is still a matter of concern. Advances in diffractive optics could provide for laser systems that could be used for engraving or cutting of micro-scale patterns at high speeds. In our paper we focus on the design of diffractive elements which can be used for this special application. It is a common desire in material processing to apply 'discrete' as well as 'continuous' beam patterns. Especially, the latter case is difficult to handle as typical micro-scale patterns are characterized by bad band-limitation properties, and as speckles can easily occur in beam patterns. It is shown in this paper that a standard iterative design method usually fails to obtain diffractive elements that generate diffraction patterns with acceptable quality. Insights gained from an analysis of the design problems are used to optimize the iterative design method. We demonstrate applicability and success of our approach by the design of diffractive phase elements that generate a discrete and a continuous 'Y2K' pattern.

Teiwes, Stephan; Krueger, Sven; Wernicke, Guenther K.; Ferstl, Margit

2000-03-01

245

Automatic test data generation for path testing using a new stochastic algorithm  

Microsoft Academic Search

Software testing is an important activity of the software development process, and automate test data generation contributes to reduce cost and time efforts. Path testing is a complex problem and metaheuristics have been pro- posed to deal with it. In this paper, an initial assessment of the efficacy of a re- cently proposed metaheuristic, the Generalized Extremal Optimization (GEO), in

Bruno T. de Abreu; Eliane Martins; Fabiano L. de Sousa

246

Testing and Functions of the J2X Gas Generator  

NASA Technical Reports Server (NTRS)

The Ares I, NASA s new solid rocket based crew launch vehicle, is a two stage in line rocket that has made its waytothe forefront of NASA s endeavors. The Ares I s Upper Stage (US) will be propelled by a J-2X engine which is fueled by liquid hydrogen and liquid oxygen. The J-2X is a variation based on two of its predecessor s, the J-2 and J-2S engines. ET50 is providing the design support for hardware required to run tests on the J-2X Gas Generator (GG) that increases the delivery pressure of the supplied combustion fuels that the engine burns. The test area will be running a series of tests using different lengths and curved segments of pipe and different sized nozzles to determine the configuration that best satisfies the thrust, heat, and stability requirements for the engine. I have had to research the configurations that are being tested and gain an understanding of the purpose of the tests. I then had to research the parts that would be used in the test configurations. I was taken to see parts similar to the ones used in the test configurations and was allowed to review drawings and dimensions used for those parts. My job over this summer has been to use the knowledge I have gained to design, model, and create drawings for the un-fabricated parts that are necessary for the J-2X Workhorse Gas Generator Phase IIcTest.

Miller, Nicholas

2009-01-01

247

Automatic Generation of Primary Sequence Patterns from Sets of Related Protein Sequences  

Microsoft Academic Search

We have developed a computer algorithm that can extract the pattern of conserved primary sequence elements common to all members of a homologous protein family. The method involves clustering the pairwise similarity scores among a set of related sequences to generate a binary dendrogram (tree). The tree is then reduced in a stepwise manner by progressively replacing the node connecting

Randall F. Smith; Temple F. Smith

1990-01-01

248

Dynamic walking pattern generation for a humanoid robot based on optimal gradient method  

Microsoft Academic Search

Describes a method in which walking patterns based on the ZMP (zero moment point) are generated by a simple search algorithm; OGM (optimal gradient method). This approach has advantages in algorithmic simplicity and height generality. First, the designer gives prescribed time trajectories of both feet, hands and a reference of ZMP. Second, initial trajectories of a trunk are determined on

K. Nagasaka; H. Inoue; M. Inaba

1999-01-01

249

Modelling spinal circuitry involved in locomotor pattern generation: insights from deletions during fictive locomotion  

Microsoft Academic Search

The mammalian spinal cord contains a locomotor central pattern generator (CPG) that can produce alternating rhythmic activity of flexor and extensor motoneurones in the absence of rhythmic input and proprioceptive feedback. During such fictive locomotor activity in decerebrate cats, spontaneous omissions of activity occur simultaneously in multiple agonist motoneurone pools for a number of cycles. During these 'deletions', antagonist motoneurone

Ilya A. Rybak; Natalia A. Shevtsova; M. Lafreniere-Roula; David A. McCrea

2006-01-01

250

Generation of spatially periodic patterns by a mechanical instability: a mechanical alternative to the Turing model  

Microsoft Academic Search

SUMMARY We have studied the generation of spatial patterns created by mechanical (rather than chemi- cal) instabilities. When dissociated fibroblasts are suspended in a gel of reprecipitated collagen, and the contraction of the gel as a whole is physically restrained by attachment of its margin to a glass fibre meshwork, then the effect of the fibroblasts' traction is to break

ALBERT K. HARRIS; DAVID STOPAK; PATRICIA WARNER

251

Gait pattern generation with knee stretch motion for biped robot using toe and heel joints  

Microsoft Academic Search

This paper presents a new alternative methodology to generate gait pattern with a knee stretched motion for biped robot utilizing toe and heel joints. During walking sequence, human heels act as passive joints that create some support area which enhances the stability of human walking. This research tries to replace human-heel like mechanism with a heel joint in the biped

Nandha Handharu; Jungwon Yoon; Gabsoon Kim

2008-01-01

252

Investigation of the patterned surface modification on 3D vortex flow generation in a micropipe  

NASA Astrophysics Data System (ADS)

The effects of patterned surface modification on 3D vortex flow generation in a micro capillary tube under a very low Reynolds number have been investigated. Microfabrication technology was successfully employed to pattern surface charges on the inner surfaces of a round capillary tube, which form non-uniform zeta potentials. This technique extends the heterogeneous surfaces from a flat surface to a curved surface. 3D vortices are visualized and measured at the vicinity of tube walls when an electric field is applied across the surfaces utilizing micro resolution PIV. It demonstrated that 3D vortices can also be generated by the patterned surface charges with the same polarity patches. Experimental results have been compared with numerical simulations using CFD-ACE+.

Zhang, P.; Qiu, H. H.

2008-11-01

253

Fast multiphoton microfabrication of freeform polymer microstructures by spatiotemporal focusing and patterned generation  

NASA Astrophysics Data System (ADS)

One of the limits of a conventional multiphoton microfabrication is its low throughput due to the sequential nature of scanning process. In this study, a multiphoton microfabrication system based on spatiotemporal focusing and patterned excitation has been developed to provide freeform polymer microstructures fast. The system integrates a 10 kHz repetition rate ultrafast amplifier featuring strong instantanrror device generating designed patterns at the focal plane. As the result, three-dimensional freeform polymer microstructures using Rose Bengal as the photoinitiator are created by sequentially stacking up two-dimensional (2D) structures layer-by-layer. The size of each 2D fabrication area can be larger than 100 × 100 ?m2. Compared with scanning process or fixed mask pattern generation, this approach provides two- or three-fold fabrication speed and freeform microstructures. Furthermore, the system is capable of optical sectioning the fabricated microstructures for providing 3D inspection.

Li, Y.-C.; Cheng, L.-C.; Lien, C.-H.; Chang, C.-Y.; Yen, W.-C.; Chen, S.-J.

2012-10-01

254

Using Model Checking to Generate Tests from Specifications.  

National Technical Information Service (NTIS)

The authors apply a model checker to the problem of test generation using a new application of mutation analysis. The authors define syntactic operators, each of which produces a slight variation on a given model. The operators define a form of mutation a...

P. E. Ammann P. E. Black W. J. Majurski

1998-01-01

255

Automatic Generation of Tests from Domain and Multimedia Ontologies  

ERIC Educational Resources Information Center

The aim of this article is to present an approach for generating tests in an automatic way. Although other methods have been already reported in the literature, the proposed approach is based on ontologies, representing both domain and multimedia knowledge. The article also reports on a prototype implementation of this approach, which…

Papasalouros, Andreas; Kotis, Konstantinos; Kanaris, Konstantinos

2011-01-01

256

Automatic Test Generation for Java-Card Applets  

Microsoft Academic Search

Open-cards have introduced a new life cycle for smart card embedded applications. In the case of Java Card, they have raised the problem of embedded object-oriented applet validation. In this article, we describe a methodology for Java Card applet verification, and its application on a case study. This methodology is based on automatic test generation. We first take benefits of

Hugues Martin; Lydie Du Bousquet

2000-01-01

257

A System to Generate Test Data and Symbolically Execute Programs  

Microsoft Academic Search

This paper describes a system that attempts to generate test data for programs written in ANSI Fortran. Given a path, the system symbolically executes the path and creates a set of constraints on the program's input variables. If the set of constraints is linear, linear programming techniques are employed to obtain a solution. A solution to the set of constraints

Lori A. Clarke

1976-01-01

258

Selection of potentially testable path delay faults for test generation  

Microsoft Academic Search

We present a method of path selection and test generation for path delay faults. The proposed method addresses the fact that logic circuits typically have very large numbers of paths, and a large percentage of these paths are typically untestable. The proposed method selects a set of potentially testable long paths by utilizing non-enumerative identification of untestable paths and removing

Atsushi Murakami; Seiji Kajihara; Tsutomu Sasao; Irith Pomeranz; Sudhakar M. Reddy

2000-01-01

259

Scalable automated test generation using coverage guidance and random search  

Microsoft Academic Search

Dynamic symbolic execution has been shown to be an effective technique for automated test input generation. When applied to large-scale programs, its scalability however is limited due to the combinatorial explosion of the path space and the high cost of computation. Several sophisticated search strategies have been proposed to better guide dynamic symbolic execution towards achieving high code coverage. While

Alvis C. M. Fong; Russel Pears

2012-01-01

260

A Nationwide Pilot Architecture for Testing Next Generation Networks  

Microsoft Academic Search

In this paper we describe design and implementation of a next generation network (NGN) pilot which is a testbed used to test different services, features, protocols, etc that can be delivered or used in NGN. This Pilot is considered as a part of Iran telecommunications 5-year master plan which is going to migrate to NGN networks. The process of implementing

Mahmoud Pirhadi; Yazdan Nasr Harandi; Mojtaba Yaghoubi Waskasi; Abbas Iravani Tabrizipoor; Mansour Mirzabaghi

2006-01-01

261

Coverage directed test generation for functional verification using bayesian networks  

Microsoft Academic Search

Functional verification is widely acknowledged as the bottleneck in the hardware design cycle. This paper addresses one of the main challenges of simulation based verification (or dynamic verification), by providing a new approach for Coverage Directed Test Generation (CDG). This approach is based on Bayesian networks and computer learning techniques. It provides an efficient way for closing a feedback loop

Shai Fine; Avi Ziv

2003-01-01

262

KIVA-I MHD Generator Modifications and Tests.  

National Technical Information Service (NTIS)

The AFAPL-MHD Facility (KIVA-I) was used to conduct an extensive series of tests on the pegwall diagonally connected generator. Extensive knowledge was gained in the areas of conductivity, oxygen-to-fuel ratios, interelectrode connection angles, seed part...

L. W. Buechler R. A. Nimmo

1973-01-01

263

Electronic test instrument generates extremely small current signals  

NASA Technical Reports Server (NTRS)

Generator produces dynamic test signals in the range from 0.0001 and 10 to the minus 12th power amperes. It involves an extension of the technique of applying a triangular voltage waveform to a small capacitor to obtain a square-wave output current. The effects of stray capacitance are minimized by appropriate shielding.

Brookshier, W. K.

1967-01-01

264

Using Computer Generated Holograms to Test Aspheric Wavefronts  

Microsoft Academic Search

The use of computer generated holograms for the testing of aspheric wavefronts is described. An analysis of the errors produced by emulsion movement, incorrect hologram size and position, and distor- tion in hologram plotter and photoreduction lens is given, and it is shown that all the errors are propor- tional to the slope of the aspheric wavefront. Experimental results verifying

J. C. Wyant; V. P. Bennett

1972-01-01

265

Patterns  

NSDL National Science Digital Library

Directions: Play the games that are listed. Do not go to another site. Be sure to take turns with your partner. First, learn to complete a pattern by playing "Which One?." Next, keep practicing patterns by playing "Pattern Mania." Finally, determine what type of pattern each set is by playing "Which pattern is it?." ...

Hinson, Mrs.

2011-10-03

266

Automated Test Case Generation for an Autopilot Requirement Prototype  

NASA Technical Reports Server (NTRS)

Designing safety-critical automation with robust human interaction is a difficult task that is susceptible to a number of known Human-Automation Interaction (HAI) vulnerabilities. It is therefore essential to develop automated tools that provide support both in the design and rapid evaluation of such automation. The Automation Design and Evaluation Prototyping Toolset (ADEPT) enables the rapid development of an executable specification for automation behavior and user interaction. ADEPT supports a number of analysis capabilities, thus enabling the detection of HAI vulnerabilities early in the design process, when modifications are less costly. In this paper, we advocate the introduction of a new capability to model-based prototyping tools such as ADEPT. The new capability is based on symbolic execution that allows us to automatically generate quality test suites based on the system design. Symbolic execution is used to generate both user input and test oracles user input drives the testing of the system implementation, and test oracles ensure that the system behaves as designed. We present early results in the context of a component in the Autopilot system modeled in ADEPT, and discuss the challenges of test case generation in the HAI domain.

Giannakopoulou, Dimitra; Rungta, Neha; Feary, Michael

2011-01-01

267

Improved Ant Algorithms for Software Testing Cases Generation  

PubMed Central

Existing ant colony optimization (ACO) for software testing cases generation is a very popular domain in software testing engineering. However, the traditional ACO has flaws, as early search pheromone is relatively scarce, search efficiency is low, search model is too simple, positive feedback mechanism is easy to porduce the phenomenon of stagnation and precocity. This paper introduces improved ACO for software testing cases generation: improved local pheromone update strategy for ant colony optimization, improved pheromone volatilization coefficient for ant colony optimization (IPVACO), and improved the global path pheromone update strategy for ant colony optimization (IGPACO). At last, we put forward a comprehensive improved ant colony optimization (ACIACO), which is based on all the above three methods. The proposed technique will be compared with random algorithm (RND) and genetic algorithm (GA) in terms of both efficiency and coverage. The results indicate that the improved method can effectively improve the search efficiency, restrain precocity, promote case coverage, and reduce the number of iterations.

Yang, Shunkun; Xu, Jiaqi

2014-01-01

268

FISH INVASIONS IN CALIFORNIA WATERSHEDS: TESTING HYPOTHESES USING LANDSCAPE PATTERNS  

Microsoft Academic Search

An important goal of invasion biology is to identify physical and environ- mental characteristics that may make a region particularly receptive to invasions. The inland waters of California (USA) are highly invaded, particularly by fishes, although there is wide variation in numbers of nonnative fishes across the state's watersheds. Here we examine patterns of fish invasions in California watersheds and

Michael P. Marchetti; Theo Light; Peter B. Moyle; Joshua H. Viers

2004-01-01

269

Leisure-Activity Patterns and Marital Satisfaction: A Further Test.  

ERIC Educational Resources Information Center

Examined relationship among four types of leisure-activity patterns and marital satisfaction of 318 married persons, and at five marital career stages and at high and low levels of stress. Results indicated direction and strength of relationship between leisure and marital satisfaction were contingent upon perceived communication during leisure…

Holman, Thomas B.; Jacquart, Mary

1988-01-01

270

Motor unit firing rate patterns during voluntary muscle force generation: a simulation study  

NASA Astrophysics Data System (ADS)

Objective. Muscle force is generated by a combination of motor unit (MU) recruitment and changes in the discharge rate of active MUs. There have been two basic MU recruitment and firing rate paradigms reported in the literature, which describe the control of the MUs during force generation. The first (termed the reverse ‘onion skin’ profile), exhibits lower firing rates for lower threshold units, with higher firing rates occurring in higher threshold units. The second (termed the ‘onion skin’ profile), exhibits an inverse arrangement, with lower threshold units reaching higher firing rates. Approach. Using a simulation of the MU activity in a hand muscle, this study examined the force generation capacity and the variability of the muscle force magnitude at different excitation levels of the MU pool under these two different MU control paradigms. We sought to determine which rate/recruitment scheme was more efficient for force generation, and which scheme gave rise to the lowest force variability. Main results. We found that the force output of both firing patterns leads to graded force output at low excitation levels, and that the force generation capacity of the two different paradigms diverged around 50% excitation. In the reverse ‘onion skin’ pattern, at 100% excitation, the force output reached up to 88% of maximum force, whereas for the ‘onion skin’ pattern, the force output only reached up to 54% of maximum force at 100% excitation. The force variability was lower at the low to moderate force levels under the ‘onion skin’ paradigm than with the reverse ‘onion skin’ firing patterns, but this effect was reversed at high force levels. Significance. This study captures the influence of MU recruitment and firing rate organization on muscle force properties, and our results suggest that the different firing organizations can be beneficial at different levels of voluntary muscle force generation and perhaps for different tasks.

Hu, Xiaogang; Rymer, William Z.; Suresh, Nina L.

2014-04-01

271

46 CFR 111.12-5 - Construction and testing of generators.  

Code of Federal Regulations, 2010 CFR

...false Construction and testing of generators. 111.12-5 Section 111...SYSTEMS-GENERAL REQUIREMENTS Generator Construction and Circuits § 111...12-5 Construction and testing of generators. Each generator...

2010-10-01

272

46 CFR 111.12-5 - Construction and testing of generators.  

Code of Federal Regulations, 2010 CFR

...false Construction and testing of generators. 111.12-5 Section 111...SYSTEMS-GENERAL REQUIREMENTS Generator Construction and Circuits § 111...12-5 Construction and testing of generators. Each generator...

2009-10-01

273

46 CFR 111.12-5 - Construction and testing of generators.  

Code of Federal Regulations, 2013 CFR

...false Construction and testing of generators. 111.12-5 Section 111...SYSTEMS-GENERAL REQUIREMENTS Generator Construction and Circuits § 111...12-5 Construction and testing of generators. Each generator...

2013-10-01

274

Gas Generation from K East Basin Sludges - Series I Testing  

SciTech Connect

This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor and canister sludge. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge. The overall goals for this testing were to collect detailed gas generation rate and composition data to ascertain the quantity and reactivity of the metallic uranium (and other reactive species) present in the K Basin sludge. The gas generation evaluation included four large-scale vessels (850 ml) and eight small-scale vessels (30 ml) in an all-metal, leak tight system. The tests were conducted for several thousand hours at ambient and elevated temperatures (32 C, 40 C, 60 C, 80 C, and 95 C) to accelerated the reactions and provide conclusive gas generation data within a reasonable testing period. The sludge used for these tests was collected from the KE Basin floor and canister barrels (containing damaged spent fuel elements) using a consolidated sampling technique (i.e., material from several locations was combined to form ''consolidated samples''). Portions of these samples were sieved to separate particles greater than 250 m (P250) from particle less than 250 m (M250). This separation was performed to mimic the separation operations that are planned during the retrieval of certain K Basin sludge types and to gain a better understanding of how uranium metal is distributed in the sludge. The corrosion rate of the uranium metal particles in the sludge was found to agree reasonably well with corrosion rates reported in the literature.

Delegard, Calvin H.; Bryan, Samuel A.; Schmidt, Andrew J.; Bredt, Paul R.; King, Christopher M.; Sell, Rachel L.; Burger, Leland L.; Silvers, Kurt L.

2000-09-12

275

Neuromorphic control of stepping pattern generation: a dynamic model with analog circuit implementation.  

PubMed

Animals such as stick insects can adaptively walk on complex terrains by dynamically adjusting their stepping motion patterns. Inspired by the coupled Matsuoka and resonate-and-fire neuron models, we present a nonlinear oscillation model as the neuromorphic central pattern generator (CPG) for rhythmic stepping pattern generation. This dynamic model can also be used to actuate the motoneurons on a leg joint with adjustable driving frequencies and duty cycles by changing a few of the model parameters while operating such that different stepping patterns can be generated. A novel mixed-signal integrated circuit design of this dynamic model is subsequently implemented, which, although simplified, shares the equivalent output performance in terms of the adjustable frequency and duty cycle. Three identical CPG models being used to drive three joints can make an arthropod leg of three degrees of freedom. With appropriate initial circuit parameter settings, and thus suitable phase lags among joints, the leg is expected to walk on a complex terrain with adaptive steps. The adaptation is associated with the circuit parameters mediated both by the higher level nervous system and the lower level sensory signals. The model is realized using a 0.3- complementary metal-oxide-semiconductor process and the results are reported. PMID:24808545

Zhijun Yang; Cameron, K; Lewinger, W; Webb, B; Murray, A

2012-03-01

276

NASA Fastrac Engine Gas Generator Component Test Program and Results  

NASA Technical Reports Server (NTRS)

Low cost access to space has been a long-time goal of the National Aeronautics and Space Administration (NASA). The Fastrac engine program was begun at NASA's Marshall Space Flight Center to develop a 60,000-pound (60K) thrust, liquid oxygen/hydrocarbon (LOX/RP), gas generator-cycle booster engine for a fraction of the cost of similar engines in existence. To achieve this goal, off-the-shelf components and readily available materials and processes would have to be used. This paper will present the Fastrac gas generator (GG) design and the component level hot-fire test program and results. The Fastrac GG is a simple, 4-piece design that uses well-defined materials and processes for fabrication. Thirty-seven component level hot-fire tests were conducted at MSFC's component test stand #116 (TS116) during 1997 and 1998. The GG was operated at all expected operating ranges of the Fastrac engine. Some minor design changes were required to successfully complete the test program as development issues arose during the testing. The test program data results and conclusions determined that the Fastrac GG design was well on the way to meeting the requirements of NASA's X-34 Pathfinder Program that chose the Fastrac engine as its main propulsion system.

Dennis, Henry J., Jr.; Sanders, T.

2000-01-01

277

Defense reaction in the pond snail Planorbis corneus. II. Central pattern generator.  

PubMed

1. In the isolated CNS of the pond snail Planorbis corneus, spontaneous bursts of activity in the motor neurons (MNs) supplying the columellar muscle were occasionally observed. The biphasic pattern of this activity, with a shorter (3-5 s) initial burst and longer (20-40 s) subsequent burst, was similar to that of the motor output during the general ("whole-body") defense reaction. In preparations consisting of the CNS isolated with the columellar muscle or with the lung, spontaneous biphasic contractions of the muscle as well as openings of the pneumostome with a temporal pattern characteristic of the defense reaction were observed. These findings demonstrated that the efferent pattern of the defense reaction in the snail is, to a large extent, produced by a special neuronal mechanism (the central pattern generator, CPG) triggered by the sensory input, rather than generated by ongoing processing of sensory input. The CPG consists of two components responsible for generation of two phases of the defense reaction. A characteristic feature of the CPG is that the magnitude of its response depends in a graded fashion on the strength of the initial stimulus. 2. In the pleural ganglia there are at least two electrically connected interneurons (DRN1s) that play an important role in generation of the first phase of the defense reaction. Processes of the DRN1s form a ring passing through all (except pedal and buccal) ganglia. The DRN1s received an excitatory input when a peripheral nerve was stimulated. They generated action potentials of long (0.2-2 s) duration. The DRN1 from the right ganglion was studied in more detail.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8201429

Arshavsky, Y I; Deliagina, T G; Okshtein, I L; Orlovsky, G N; Panchin, Y V; Popova, L B

1994-03-01

278

Multiple Rhythmic States in a Model of the Respiratory Central Pattern Generator  

PubMed Central

The three-phase respiratory pattern observed during normal breathing changes with alterations in metabolic or physiological conditions. A recent study using in situ perfused rat brain preparations demonstrated a reorganization of the respiratory pattern with sequential reduction of the brain stem respiratory network. Specifically, with removal of the pons, the normal three-phase pattern transformed to a two-phase inspiratory–expiratory pattern and, with more caudal transections, to one-phase, intrinsically generated inspiratory oscillations. A minimal neural network proposed to reproduce these transformations includes 1) a ringlike mutually inhibitory network composed of the postinspiratory, augmenting expiratory, and early-inspiratory neurons and 2) an excitatory preinspiratory neuron, with persistent sodium current (INaP)-dependent intrinsic bursting properties, that dynamically participates in the expiratory–inspiratory phase transition and inspiratory phase generation. We used activity-based single-neuron models and applied numerical simulations, bifurcation methods, and fast–slow decomposition to describe the behavior of this network in the functional states corresponding to the three-, two-, and one-phase oscillatory regimes, as well as to analyze the transitions between states and between respiratory phases within each state. We demonstrate that, although INaP is not necessary for the generation of three- and two-phase oscillations, it contributes to control of the oscillation period in each state. We also show that the transitions between states can be produced by progressive changes of drives to particular neurons and proceed through intermediate regimes, featuring high-amplitude late-expiratory and biphasic-expiratory activities or ectopic burst generation. Our results provide important insights for understanding the state-dependent mechanisms for respiratory rhythm generation and control.

Rubin, Jonathan E.; Shevtsova, Natalia A.; Ermentrout, G. Bard; Smith, Jeffrey C.; Rybak, Ilya A.

2009-01-01

279

Testing of ground conductors with artificially generated lightning current  

SciTech Connect

Alternative conductors for lightning protection applications favorable for use in mobile systems have been tested to demonstrate high levels of protection against maximal lightning events. The method of determining the survivability of the down conductors was to expose each type of conductor to maximal lightning events generated by a large Marx capacitor bank. Each type of conductor was tested until mechanical failure occurred or until it survived four exposures to the lightning event. A test to determine the effect of physical damage on conductor performance was also conducted. A theory attributing interstrand or intraconductor magnetic forces, rather than ohmic heating, as the primary cause of conductor failure is proposed. Results indicate that two types of tested conductor exist which can provide protection against maximal lightning events, yet have properties that lend themselves to mobile application.

Tobias, J.M. [USA CECOM, Fort Monmouth, NJ (United States)] [USA CECOM, Fort Monmouth, NJ (United States)

1996-05-01

280

Testing and evaluation of Second-Generation Heliostat mirror modules  

SciTech Connect

The testing and evaluation of the Second Generation Heliostat mirror modules are reported here. It was found that all of the previous design problems of mirror modules, such as silver corrosion, thermal defocus, and high glass stress, were eliminated by one or more of these designs. The single most important conclusion to be drawn from this program is that laminated glass mirror module designs are the most technically conservative; it is Sandia's recommendation that this concept be used for near-term applications. Two other Second Generation designs were found to have potential for reduced weight and improved performance, but one design required some significant design changes, and both require further outdoor testing to better estimate their lifetime potential.

Burolla, V.P.; Delameter, W.R.

1982-01-01

281

Automatic Generation of Test Oracles - From Pilot Studies to Application  

NASA Technical Reports Server (NTRS)

There is a trend towards the increased use of automation in V&V. Automation can yield savings in time and effort. For critical systems, where thorough V&V is required, these savings can be substantial. We describe a progression from pilot studies to development and use of V&V automation. We used pilot studies to ascertain opportunities for, and suitability of, automating various analyses whose results would contribute to V&V. These studies culminated in the development of an automatic generator of automated test oracles. This was then applied and extended in the course of testing an Al planning system that is a key component of an autonomous spacecraft.

Feather, Martin S.; Smith, Ben

1998-01-01

282

Facility for generating crew waste water product for ECLSS testing  

NASA Technical Reports Server (NTRS)

An End-use Equipment Facility (EEF) has been constructed which is used to simulate water interfaces between the Space Station Freedom Environmental Control and Life Support Systems (ECLSS) and man systems. The EEF is used to generate waste water to be treated by ECLSS water recovery systems. The EEF will also be used to close the water recovery loop by allowing test subjects to use recovered hygiene and potable water during several phases of testing. This paper describes the design and basic operation of the EEF.

Buitekant, Alan; Roberts, Barry C.

1990-01-01

283

BRH Test Pattern for Gamma Camera Performance (an Evaluator).  

National Technical Information Service (NTIS)

The patent is a test phantom for testing the performance of gamma cameras comprises a plate imprevious to gamma rays having an orthogonal array of apertures defined there-through. The apertures are uniform in size and are arranged in columns and rows. The...

P. Paras

1983-01-01

284

A Noise Generator for Analog-to-Digital Converter Testing  

Microsoft Academic Search

This paper describes the implementation of a white noise generator to be used as the input signal of a new method for testing analog-to-digital converters in order to detect and to evaluate integral and differential non-linearity errors. The main goal of this method is to avoidthe comparison of the analog-to-digital output with a known and very precise reference input. The

M. G. C. Flores; M. Negreiros; L. Carro; A. A. Susin

2002-01-01

285

Testing and evaluation of second-generation heliostat mirror modules  

NASA Astrophysics Data System (ADS)

The testing and evaluation of the second generation heliostat mirror modules are reported. It was found that all of the previous design problems of mirror modules, such as silver corrosion, thermal defocus, and high glass stress, were eliminated by one or more of these designs. The single most important conclusion to be drawn from this program is that laminated glass mirror module designs are the most technically conservative; it is recommended that this concept be used for near term applications.

Burolla, V. P.; Delameter, W. R.

1982-01-01

286

Gas Generation from K East Basin Sludges - Series II Testing  

SciTech Connect

This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor, pit and canister sludge. Mixed and unmixed and fractionated KE canister sludge were tested, along with floor and pit sludges from areas in the KE Basin not previously sampled. The first report in this series focuses on gas generation from KE floor and canister sludge collected using a consolidated sampling technique. The third report presents results of gas generation testing of irradiated uranium fuel fragments with and without sludge addition. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge. This report was originally published in March 2001. In January 2004, a transcription error was discovered in the value reported for the uranium metal content of KE North Loadout Pit sample FE-3. This revision of the report corrects the U metal content of FE-3 from 0.0013 wt% to 0.013 wt%.

Bryan, Samuel A.; Delegard, Calvin H.; Schmidt, Andrew J.; Sell, Rachel L.; Silvers, Kurt L.; Gano, Susan R.; Thornton, Brenda M.

2004-04-26

287

Patterns of Word-List Generation in Mild Cognitive Impairment and Alzheimer's Disease  

Microsoft Academic Search

Patients with amnestic mild cognitive impairment (aMCI) have been described as exhibiting greater impairment on tests of category fluency than letter fluency. This has been offered as evidence that this condition represents pre-clinical Alzheimer's disease (AD). We hypothesized that this pattern of differential impairment is dependent on the specific semantic categories and initial letters selected, and is not specific to

Jason Brandt; Kevin J. Manning

2009-01-01

288

Sequence-specific cleavage of chromatin by staphylococcal nuclease can generate an atypical nucleosome pattern.  

PubMed Central

We have investigated the nucleosomal organization of ribosomal genes in the acellular slime mold Physarum polycephalum. When probed with staphylococcal nuclease, the ribosomal genes appear to be uniformly packed in nucleosomes, in an arrangement which is indistinguishable from the pattern obtained with bulk chromatin. During this study, an unusual pattern of digestion was obtained from a DNA region immediately upstream of the initiation site of rRNA transcription, in addition to the nucleosomal profile, a second regular ladder of fragments with a repeat length of 30-40 basepairs was generated from this region. We established that this pattern of degradation reflects the strong preference of staphylococcal nuclease for certain nucleotide arrangements on the DNA, rather than a particular chromatin configuration. These observations clearly show that great caution needs to be exerted whenever data from staphylococcal nuclease digestions are interpreted in terms of chromatin structure. Images

Pauli, U H; Seebeck, T; Braun, R

1982-01-01

289

A criterion study of solar irradiation patterns for the performance testing of thermosyphon solar water heaters  

Microsoft Academic Search

A Taiwan test standard was established in 1989 using outdoor daily efficiency test methods. This test standard has been implemented for 12 years with satisfactory results. However, it was also found from field applications that the pattern of solar irradiation would affect the result of the performance test. In the present study, we used a distribution factor Ri defined as

J. M Chang; M. C Shen; B. J Huang

2002-01-01

290

SOM-based Pattern Generator: Pattern Generation Based on the Backward Projection in a Self-Organizing Map and Its Applications  

NASA Astrophysics Data System (ADS)

A major feature of the self-organizing map (SOM) is a topology-preserving projection from the input layer to the competitive layer, and it has been used mainly as an analytical tool for discovering underlying rules in the given data set. Even though recent splendid progress in this area, there are few novel ideas to break such a conventional style. On the contrary, based on its distinctive nature, a new method for generating patterns through backward projection from the competitive layer to the input layer is proposed recently. Moreover, a promising technology for producing animation as a series of backward-projected patterns along with any pathways on the competitive layer is presented. Then, in order to carry out further considerations, some computer simulations with a variety of posed stick figures are tried in this paper. After training, four kinds of pathways, which correspond to different movements such as dancing, exercising and walking, are prepared. Though some of them does not contain any training samples, all of them worked well as we have intended in advance. As a result, it is found that the proposed method shows good performance and it is also confirmed its effectiveness.

Wakuya, Hiroshi; Ishiguma, Takahiro

291

Fast oscillations during gasping and other non-eupneic respiratory behaviors: Clues to central pattern generation  

PubMed Central

The mammalian nervous system exhibits fast synchronous oscillations, which are especially prominent in respiratory-related nerve discharges. In the phrenic nerve, they include high- (HFO), medium- (MFO), and low-frequency (LFO) oscillations. Because motoneurons firing at HFO-related frequencies had never been recorded, an epiphenomenological mechanism for their existence had been posited. We have recently recorded phrenic motoneurons firing at HFO-related frequencies in unanesthetized decerebrate rats and showed that they exhibit dynamic coherence with the phrenic nerve, validating synchronous motoneuronal discharge as a mechanism underlying the generation of HFO. In so doing, we have helped validate the conclusions of previous studies by us and other investigators who have used changes in fast respiratory oscillations to make inferences about central respiratory pattern generation. Here, we seek to review changes occurring in fast synchronous oscillations during non-eupneic respiratory behaviors, with special emphasis on gasping, and the inferences that can be drawn from these dynamics regarding respiratory pattern formation.

Ghali, Michael George Zaki; Marchenko, Vitaliy

2013-01-01

292

Evolving cellular automata for diversity generation and pattern recognition: deterministic versus random strategy  

NASA Astrophysics Data System (ADS)

Microbiological systems evolve to fulfil their tasks with maximal efficiency. The immune system is a remarkable example, where the distinction between self and non-self is made by means of molecular interaction between self-proteins and antigens, triggering affinity-dependent systemic actions. Specificity of this binding and the infinitude of potential antigenic patterns call for novel mechanisms to generate antibody diversity. Inspired by this problem, we develop a genetic algorithm where agents evolve their strings in the presence of random antigenic strings and reproduce with affinity-dependent rates. We ask what is the best strategy to generate diversity if agents can rearrange their strings a finite number of times. We find that endowing each agent with an inheritable cellular automaton rule for performing rearrangements makes the system more efficient in pattern-matching than if transformations are totally random. In the former implementation, the population evolves to a stationary state where agents with different automata rules coexist.

Argollo de Menezes, Marcio; Brigatti, Edgardo; Schwämmle, Veit

2013-08-01

293

Optical parametric generation of a mid-infrared continuum in orientation-patterned GaAs  

Microsoft Academic Search

We have generated an ultrabroad mid-infrared continuum by using single-pass optical parametric generation (OPG) in orientation-patterned GaAs (OP-GaAs). The spectrum spans more than an octave, from 4.5 to 10.7 µm, measured 20 dB down from the peak. The 17.5 mm long, 0.5 mm thick, all-epitaxially-grown OP-GaAs sample with a 166.6-µm quasi-phase-matching period was pumped with 3.1-3.3 µm wavelength, 1 ps

P. S. Kuo; K. L. Vodopyanov; M. M. Fejer; D. M. Simanovskii; X. Yu; J. S. Harris; D. Bliss; D. Weyburne

2006-01-01

294

Phase velocity nonuniformity-resulted beam patterns in difference frequency generation.  

PubMed

The evolution of the difference frequency generation between a planar pump wave and a focused signal wave has been numerically investigated in this paper. We show that, at the difference frequency wave, various beam patterns such as ring and moon-like, are resulted due to the nonuniform distribution of phase velocity in the focused signal wave. The subluminal and superluminal regions can be identified by the intersection of two generated beam profiles that correspond to a pair of phase-mismatches with equal value but opposite signs. PMID:19532754

Lu, Daquan; Qian, Liejia; Li, Yongzhong; Yang, Hua; Zhu, Heyuan; Fan, Dianyuan

2007-04-16

295

Models of central pattern generators for quadruped locomotionII. Secondary gaits  

Microsoft Academic Search

.   We continue the analysis of the network of symmetrically coupled cells modeling central pattern generators (CPG) for quadruped\\u000a locomotion proposed by Golubitsky, Stewart, Buono and Collins by studying secondary gaits. Secondary gaits are modeled by output signals from the CPG where each cell emits one of two different output signals along with exact phase\\u000a shifts. Examples of secondary gaits

Pietro-Luciano Buono

2001-01-01

296

Lithographic deposition of patterned metal-organic framework coatings using a photobase generator.  

PubMed

A photobase generator was used to induce metal-organic framework (MOF) nucleation upon UV irradiation. This method was further developed into a simple, one-step method for depositing patterned MOF films. Furthermore, the ability of our method to coat a single substrate with MOF films having different chemical compositions is illustrated. The method is an important step towards integrating MOF deposition with existing lithographic techniques and the incorporation of these materials into sensors and other electronic devices. PMID:24719391

Keitz, Benjamin K; Yu, Chung Jui; Long, Jeffrey R; Ameloot, Rob

2014-05-26

297

Process generating the ditribution pattern of eggs of the common cabbage butterfly, Pieris rapae crucivora  

Microsoft Academic Search

Summary  The process generating the negative binomial in the distribution pattern of eggs of the common cabbage butterfly,Pieris rapae crucivora, was investigated by releasing the female adults in a net house where cabbages were planted.\\u000a \\u000a The distribution of butterflies visited and laid an egg or more per plant followed thePoisson series under the uniform light condition, while that of eggs laid

Shiro Kobayashi

1966-01-01

298

Development of Multimode Biomimetic Robotic Fish Based on Central Pattern Generator  

Microsoft Academic Search

This paper presents the construction and motion control of a biologically inspired, multi-mode biomimetic robotic fish capable of three-dimensional locomotion. The mechanical configuration and the control system are described. The rhythmic movements of swimming are driven by the biological neural networks, called the central pattern generators (CPGs). The CPGs are modeled as nonlinear oscillators for joints and inter-joint coordination is

Wei Zhao; Junzhi Yu; Yimin Fang; Long Wang

2006-01-01

299

Modeling a vertebrate motor system: pattern generation, steering and control of body orientation.  

PubMed

The lamprey is one of the few vertebrates in which the neural control system for goal-directed locomotion including steering and control of body orientation is well described at a cellular level. In this report we review the modeling of the central pattern-generating network, which has been carried out based on detailed experimentation. In the same way the modeling of the control system for steering and control of body orientation is reviewed, including neuromechanical simulations and robotic devices. PMID:17925249

Grillner, Sten; Kozlov, Alexander; Dario, Paolo; Stefanini, Cesare; Menciassi, Arianna; Lansner, Anders; Hellgren Kotaleski, Jeanette

2007-01-01

300

Key Bifurcations of Bursting Polyrhythms in 3-Cell Central Pattern Generators  

PubMed Central

We identify and describe the key qualitative rhythmic states in various 3-cell network motifs of a multifunctional central pattern generator (CPG). Such CPGs are neural microcircuits of cells whose synergetic interactions produce multiple states with distinct phase-locked patterns of bursting activity. To study biologically plausible CPG models, we develop a suite of computational tools that reduce the problem of stability and existence of rhythmic patterns in networks to the bifurcation analysis of fixed points and invariant curves of a Poincaré return maps for phase lags between cells. We explore different functional possibilities for motifs involving symmetry breaking and heterogeneity. This is achieved by varying coupling properties of the synapses between the cells and studying the qualitative changes in the structure of the corresponding return maps. Our findings provide a systematic basis for understanding plausible biophysical mechanisms for the regulation of rhythmic patterns generated by various CPGs in the context of motor control such as gait-switching in locomotion. Our analysis does not require knowledge of the equations modeling the system and provides a powerful qualitative approach to studying detailed models of rhythmic behavior. Thus, our approach is applicable to a wide range of biological phenomena beyond motor control.

Wojcik, Jeremy; Schwabedal, Justus; Clewley, Robert; Shilnikov, Andrey L.

2014-01-01

301

Key bifurcations of bursting polyrhythms in 3-cell central pattern generators.  

PubMed

We identify and describe the key qualitative rhythmic states in various 3-cell network motifs of a multifunctional central pattern generator (CPG). Such CPGs are neural microcircuits of cells whose synergetic interactions produce multiple states with distinct phase-locked patterns of bursting activity. To study biologically plausible CPG models, we develop a suite of computational tools that reduce the problem of stability and existence of rhythmic patterns in networks to the bifurcation analysis of fixed points and invariant curves of a Poincaré return maps for phase lags between cells. We explore different functional possibilities for motifs involving symmetry breaking and heterogeneity. This is achieved by varying coupling properties of the synapses between the cells and studying the qualitative changes in the structure of the corresponding return maps. Our findings provide a systematic basis for understanding plausible biophysical mechanisms for the regulation of rhythmic patterns generated by various CPGs in the context of motor control such as gait-switching in locomotion. Our analysis does not require knowledge of the equations modeling the system and provides a powerful qualitative approach to studying detailed models of rhythmic behavior. Thus, our approach is applicable to a wide range of biological phenomena beyond motor control. PMID:24739943

Wojcik, Jeremy; Schwabedal, Justus; Clewley, Robert; Shilnikov, Andrey L

2014-01-01

302

VIP—an input pattern generator for indentifying critical voltage drop for deep sub-micron designs  

Microsoft Academic Search

We present a novel input pattern generator for dynamic power network simulation. The obtained patterns successfully identify critical voltage drop areas for a set of industrial designs, which are difficult to be found using functional vectors. The search engine of the pattern gener- ator for worst-case IR voltage drop is based on the multi- objective genetic algorithm. To achieve high

Yi-Min Jiang; Tak K. Young; Kwang-Ting Cheng

1999-01-01

303

Generating tactile afferent stimulation patterns for slip and touch feedback in neural prosthetics.  

PubMed

Current prosthetic limbs are limited by a lack of tactile feedback. Slip feedback is particularly important to inform grip. Object slip is marked by both a change in the normal grip force applied and a change in force tangential to the fingertips. In this study, we demonstrate that a new multi-axial tactile sensor composed of gold nanoparticle strain gauges is able to record slip and reconstruct the X, Y, and Z forces incident on the sensor's surface due to a slipping object. We entered the X, Y, and Z force components generated by the slip event into a noisy leaky integrate and fire model to simulate the firing responses of SA1 and FA1 afferents. We also recorded a uniaxial normal force input representative of tactile contact. A single set of SA1 model and FA1 model parameters generated realistic firing patterns for both the slip and normal force recordings. These results suggest that canonical SA1 and FA1 afferent models could be used to generate biomimetic electrical stimulation patterns for both slip and touch stimuli. When used to activate the tactile afferents of an amputee, these electrical stimulation patterns could create natural and distinguishable slip and touch percepts for closed loop control of an upper limb neural prosthesis. PMID:24111087

Rager, Danielle M; Alvares, Darren; Birznieks, Ingvars; Redmond, Stephen J; Morley, John W; Lovell, Nigel H; Vickery, Richard M

2013-01-01

304

Analysis of the central pattern generator for swimming in the mollusk Clione.  

PubMed

The pteropod mollusk Clione limacina swims by rhythmic movements of two wings. The central pattern generator (CPG) for swimming, located in the pedal ganglia, is formed by three groups of interneurons. The interneurons of the groups 7 and 8 are of crucial importance for rhythm generation. They are endogenous oscillators capable of generating rhythmic activity with a range of frequencies typical of swimming after extraction from the ganglia. This endogenous rhythmic activity is enhanced by serotonin. The interneurons 7 and 8 produce one prolonged action potential (about 100 ms in duration) per cycle. Prolonged action potentials contribute to determining the duration of the cycle phases. The interneurons of two groups inhibit one another determining their reciprocal activity. The putative transmitters of groups 7 and 8 interneurons are glutamate and acetylcholine, respectively. Transition from one phase to the other is facilitated by the plateau interneurons of group 12 that contribute to termination of one phase and to initiation of the next phase. Maintaining the rhythm generation and transition from one phase to the other is also promoted by postinhibitory rebound. The redundant organization of the swimming generator guarantees the high reliability of its operation. Generation of the swimming output persisted after the inhibitory input from interneurons 8 to 7 had been blocked by atropine. Activity of the swimming generator is controlled by a set of command neurons that activate, inhibit or modulate the operation of the swimming CPG in relation to a behaviorally relevant context. PMID:9928301

Arshavsky, Y I; Deliagina, T G; Orlovsky, G N; Panchin, Y V; Popova, L B; Sadreyev, R I

1998-11-16

305

Performance evaluations of MHD generator tests at CDIF  

NASA Astrophysics Data System (ADS)

Experimental data from CDIF coal-fired MHD generator test 90-DIAG-3 are analyzed. The results of two independent studies are presented and compared. Both studies impose experimental data upon modeling to derive information on plasma properties and electrical loss mechanisms. The first technique applies routine electrical data to special solutions of the MHD electrical equations to determine gross electrophysical properties and nonuniformity parameters of the generator medium (plasma plus slag) over one pitch control volumes along the length of the MHD channel. The second technique pits a predictive 1D MHD generator model against input experimental Hall voltage data. The generator model solves for the MHD plasmadynamic and electrical processes required to fit the experimental voltage distribution to determine plasma properties with wall and electrical losses. Among the parameters that are estimated by these methods are conductivity, Hall parameter, interelectrode resistances, and the plasma nonuniformity factors (e.g., G). The magnitude of leakage current (slag or otherwise) can also inferred from these analyses.

Daniel, V. W.; Lineberry, J. T.; Wu, Y. C. L.

1992-01-01

306

Exact distribution of a pattern in a set of random sequences generated by a Markov source: applications to biological data  

PubMed Central

Background In bioinformatics it is common to search for a pattern of interest in a potentially large set of rather short sequences (upstream gene regions, proteins, exons, etc.). Although many methodological approaches allow practitioners to compute the distribution of a pattern count in a random sequence generated by a Markov source, no specific developments have taken into account the counting of occurrences in a set of independent sequences. We aim to address this problem by deriving efficient approaches and algorithms to perform these computations both for low and high complexity patterns in the framework of homogeneous or heterogeneous Markov models. Results The latest advances in the field allowed us to use a technique of optimal Markov chain embedding based on deterministic finite automata to introduce three innovative algorithms. Algorithm 1 is the only one able to deal with heterogeneous models. It also permits to avoid any product of convolution of the pattern distribution in individual sequences. When working with homogeneous models, Algorithm 2 yields a dramatic reduction in the complexity by taking advantage of previous computations to obtain moment generating functions efficiently. In the particular case of low or moderate complexity patterns, Algorithm 3 exploits power computation and binary decomposition to further reduce the time complexity to a logarithmic scale. All these algorithms and their relative interest in comparison with existing ones were then tested and discussed on a toy-example and three biological data sets: structural patterns in protein loop structures, PROSITE signatures in a bacterial proteome, and transcription factors in upstream gene regions. On these data sets, we also compared our exact approaches to the tempting approximation that consists in concatenating the sequences in the data set into a single sequence. Conclusions Our algorithms prove to be effective and able to handle real data sets with multiple sequences, as well as biological patterns of interest, even when the latter display a high complexity (PROSITE signatures for example). In addition, these exact algorithms allow us to avoid the edge effect observed under the single sequence approximation, which leads to erroneous results, especially when the marginal distribution of the model displays a slow convergence toward the stationary distribution. We end up with a discussion on our method and on its potential improvements.

2010-01-01

307

Investigation, Analysis, and Testing of Self-contained Oxygen Generators  

NASA Technical Reports Server (NTRS)

Self Contained Oxygen Generators (SCOGs) have widespread use in providing emergency breathing oxygen in a variety of environments including mines, submarines, spacecraft, and aircraft. These devices have definite advantages over storing of gaseous or liquid oxygen. The oxygen is not generated until a chemical briquette containing a chlorate or perchlorate oxidizer and a solid metallic fuel such as iron is ignited starting a thermal decomposition process allowing gaseous oxygen to be produced. These devices are typically very safe to store, easy to operate, and have primarily only a thermal hazard to the operator that can be controlled by barriers or furnaces. Tens of thousands of these devices are operated worldwide every year without major incident. This report examines the rare case of a SCOG whose behavior was both abnormal and lethal. This particular type of SCOG reviewed is nearly identical to a flight qualified version of SCOG slated for use on manned space vehicles. This Investigative Report is a compilation of a NASA effort in conjunction with other interested parties including military and aerospace to understand the causes of the particular SCOG accident and what preventative measures can be taken to ensure this incident is not repeated. This report details the incident and examines the root causes of the observed SCOG behavior from forensic evidence. A summary of chemical and numerical analysis is provided as a background to physical testing of identical SCOG devices. The results and findings of both small scale and full scale testing are documented on a test-by-test basis along with observations and summaries. Finally, conclusions are presented on the findings of this investigation, analysis, and testing along with suggestions on preventative measures for any entity interested in the safe use of these devices.

Keddy, Christopher P.; Haas, Jon P.; Starritt, Larry

2008-01-01

308

Implementation of a Data Packet Generator Using Pattern Matching for Wearable ECG Monitoring Systems.  

PubMed

In this paper, a packet generator using a pattern matching algorithm for real-time abnormal heartbeat detection is proposed. The packet generator creates a very small data packet which conveys sufficient crucial information for health condition analysis. The data packet envelopes real time ECG signals and transmits them to a smartphone via Bluetooth. An Android application was developed specifically to decode the packet and extract ECG information for health condition analysis. Several graphical presentations are displayed and shown on the smartphone. We evaluate the performance of abnormal heartbeat detection accuracy using the MIT/BIH Arrhythmia Database and real time experiments. The experimental result confirm our finding that abnormal heart beat detection is practically possible. We also performed data compression ratio and signal restoration performance evaluations to establish the usefulness of the proposed packet generator and the results were excellent. PMID:25029280

Noh, Yun Hong; Jeong, Do Un

2014-01-01

309

Effective hydrogen generator testing for on-site small engine  

NASA Astrophysics Data System (ADS)

We propose a new concept of hydrogen generator testing for on-site small engine. In general, there is a trade-off between simpler vehicle design and infrastructure issues, for instance, liquid fuels such as gasoline and methanol for small engine use. In this article we compare the hydrogen gases combination the gasoline between normal systems (gasoline only) for small engine. The advantage of the hydrogen combines gasoline for small engine saving the gasoline 25%. Furthermore, the new concept of hydrogen combination for diesel engine, bio-diesel engine, liquid petroleum gas (LPG), natural gas vehicle (NGV), which is discussed in details.

Chaiwongsa, Praitoon; Pornsuwancharoen, Nithiroth; Yupapin, Preecha P.

310

Radioisotope thermoelectric generator/thin fragment impact test  

SciTech Connect

The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the convertor housing, failure of one fueled clad, and release of a small quantity of fuel.

Reimus, M.A.H.; Hinckley, J.E.

1998-12-31

311

End-on radioisotope thermoelectric generator impact tests  

SciTech Connect

The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of [sup 238]Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). The modular GPHS design was developed to address both survivability during launch abort and return from orbit. The first two RTG Impact Tests were designed to provide information on the response of a fully loaded RTG to end-on impact against a concrete target. The results of these tests indicated that at impact velocities up to 57 m/s the converter shell and internal components protect the GPHS capsules from excessive deformation. At higher velocities, some of the internal components of the RTG interact with the GPHS capsules to cause excessive localized deformation and failure.

Reimus, M.A.H.; Hhinckley, J.E.

1997-01-01

312

Micropunching Lithography for Generating Micro- and Submicron-patterns on Polymer Substrates  

PubMed Central

Conducting polymers have attracted great attention since the discovery of high conductivity in doped polyacetylene in 19771. They offer the advantages of low weight, easy tailoring of properties and a wide spectrum of applications2,3. Due to sensitivity of conducting polymers to environmental conditions (e.g., air, oxygen, moisture, high temperature and chemical solutions), lithographic techniques present significant technical challenges when working with these materials4. For example, current photolithographic methods, such as ultra-violet (UV), are unsuitable for patterning the conducting polymers due to the involvement of wet and/or dry etching processes in these methods. In addition, current micro/nanosystems mainly have a planar form5,6. One layer of structures is built on the top surfaces of another layer of fabricated features. Multiple layers of these structures are stacked together to form numerous devices on a common substrate. The sidewall surfaces of the microstructures have not been used in constructing devices. On the other hand, sidewall patterns could be used, for example, to build 3-D circuits, modify fluidic channels and direct horizontal growth of nanowires and nanotubes. A macropunching method has been applied in the manufacturing industry to create macropatterns in a sheet metal for over a hundred years. Motivated by this approach, we have developed a micropunching lithography method (MPL) to overcome the obstacles of patterning conducting polymers and generating sidewall patterns. Like the macropunching method, the MPL also includes two operations (Fig. 1): (i) cutting; and (ii) drawing. The "cutting" operation was applied to pattern three conducting polymers4, polypyrrole (PPy), Poly(3,4-ethylenedioxythiophen)-poly(4-styrenesulphonate) (PEDOT) and polyaniline (PANI). It was also employed to create Al microstructures7. The fabricated microstructures of conducting polymers have been used as humidity8, chemical8, and glucose sensors9. Combined microstructures of Al and conducting polymers have been employed to fabricate capacitors and various heterojunctions9,10,11. The "cutting" operation was also applied to generate submicron-patterns, such as 100- and 500-nm-wide PPy lines as well as 100-nm-wide Au wires. The "drawing" operation was employed for two applications: (i) produce Au sidewall patterns on high density polyethylene (HDPE) channels which could be used for building 3D microsystems12,13,14, and (ii) fabricate polydimethylsiloxane (PDMS) micropillars on HDPE substrates to increase the contact angle of the channel15.

Chakraborty, Anirban; Liu, Xinchuan; Luo, Cheng

2012-01-01

313

Statistical Test Suite for Random and Pseudorandom Number Generators for Cryptographic Applications.  

National Technical Information Service (NTIS)

This paper discusses some aspects of selecting and testing random and pseudorandom number generators. The outputs of such generators may he used in many cryptographic applications, such as the generation of key material. Generators suitable for use in cry...

A. Rukhin J. Soto J. Nechvatal M. Smid E. Barker

2001-01-01

314

Engineering systems for the generation of patterned co-cultures for controlling cell-cell interactions  

PubMed Central

Background Inside the body, cells lie in direct contact or in close proximity to other cell types in a tightly controlled architecture that often regulates the resulting tissue function. Therefore, tissue engineering constructs that aim to reproduce the architecture and the geometry of tissues will benefit from methods of controlling cell–cell interactions with microscale resolution. Scope of the review We discuss the use of microfabrication technologies for generating patterned co-cultures. In addition, we categorize patterned co-culture systems by cell type and discuss the implications of regulating cell-cell interactions in the resulting biological function of the tissues. Major conclusions Patterned co-cultures are a useful tool for fabricating tissue engineered constructs and for studying cell–cell interactions in vitro, because they can be used to control the degree of homotypic and heterotypic cell–cell contact. In addition, this approach can be manipulated to elucidate important factors involved in cell-matrix interactions. General significance Patterned co-culture strategies hold significant potential to develop biomimetic structures for tissue engineering. It is expected that they would create opportunities to develop artificial tissues in the future.

Kaji, Hirokazu; Camci-Unal, Gulden; Langer, Robert; Khademhosseini, Ali

2010-01-01

315

Convergence of pattern generator outputs on a common mechanism of diaphragm motor unit recruitment.  

PubMed

Motor units are the final element of neuromotor control. In manner analogous to the organization of neuromotor control in other skeletal muscles, diaphragm motor units comprise phrenic motoneurons located in the cervical spinal cord that innervate the diaphragm muscle, the main inspiratory muscle in mammals. Diaphragm motor units play a primary role in sustaining ventilation but are also active in other nonventilatory behaviors, including coughing, sneezing, vomiting, defecation, and parturition. Diaphragm muscle fibers comprise all fiber types. Thus, diaphragm motor units display substantial differences in contractile and fatigue properties, but importantly, properties of the motoneuron and muscle fibers within a motor unit are matched. As in other skeletal muscles, diaphragm motor units are recruited in order such that motor units that display greater fatigue resistance are recruited earlier and more often than more fatigable motor units. The properties of the motor unit population are critical determinants of the function of a skeletal muscle across the range of possible motor tasks. Accordingly, fatigue-resistant motor units are sufficient to generate the forces necessary for ventilatory behaviors, whereas more fatigable units are only activated during expulsive behaviors important for airway clearance. Neuromotor control of diaphragm motor units may reflect selective inputs from distinct pattern generators distributed according to the motor unit properties necessary to accomplish these different motor tasks. In contrast, widely distributed inputs to phrenic motoneurons from various pattern generators (e.g., for breathing, coughing, or vocalization) would dictate recruitment order based on intrinsic electrophysiological properties. PMID:24746055

Mantilla, Carlos B; Seven, Yasin B; Sieck, Gary C

2014-01-01

316

Implementing the Spectral Test for Assessing Linear Congruential Random Number Generators.  

National Technical Information Service (NTIS)

This report contains three implementations of the spectral test for rating linear congruential random number generators. The spectral test is an important test for rating linear congruential random number generators. It requires exact integer arithmetic a...

T. R. Hopkins

1984-01-01

317

Design, fabrication, and testing of energy-harvesting thermoelectric generator  

NASA Astrophysics Data System (ADS)

An energy-harvesting thermoelectric generator (TEG) is being developed to provide power for wireless sensors used in health monitoring of Navy machinery. TEGs are solid-state devices that convert heat directly into electricity without any moving parts. In this application, the TEGs utilize the heat transfer between shipboard waste heat sources and the ambient air to generate electricity. In order to satisfy the required small design volume of less than one cubic inch, Hi-Z is using its innovative thin-film Quantum Well (QW) thermoelectric technology that will provide a factor of four increase in efficiency and a large reduction in the device volume over the currently used bulk Bi2Te3 based thermoelectics. QWs are nanostructured multi-layer films. These wireless sensors can be used to detect cracks, corrosion, impact damage, and temperature and vibration excursions as part of the Condition Based Maintenance (CBM) of the Navy ship machinery. The CBM of the ship machinery can be significantly improved by automating the process with the use of self-powered wireless sensors. These power-harvesting TEGs can be used to replace batteries as electrical power sources and to eliminate power cables and data lines. The first QW TEG module was fabricated and initial tests were successful. It is planned to conduct performance tests the entire prototype QW TEG device (consisting of the TEG module, housing, thermal insulation and the heat sink) in a simulated thermal environment of a Navy ship.

Jovanovic, Velimir; Ghamaty, Saeid

2006-04-01

318

Fictive locomotor patterns generated by tetraethylammonium application to the neonatal rat spinal cord in vitro.  

PubMed

Intrinsic spinal networks generate a locomotor rhythm characterized by alternating electrical discharges from flexor and extensor motor pools. Because this process is preserved in the rat isolated spinal cord, this preparation in vitro may be a useful model to explore methods to reactivate locomotor networks damaged by spinal injury. The present electrophysiological investigation examined whether the broad spectrum potassium channel blocker tetraethylammonium could generate locomotor-like patterns. Low (50-500 microM) concentrations of tetraethylammonium induced irregular, synchronous discharges incompatible with locomotion. Higher concentrations (1-10 mM) evoked alternating discharges between flexor and extensor motor pools, plus large depolarization of motoneurons with spike broadening. The alternating discharges were superimposed on slow, shallow waves of synchronous depolarization. Rhythmic alternating patterns were suppressed by blockers of glutamate, GABA(A) and glycine receptors, disclosing a background of depolarizing bursts inhibited by antagonism of group I metabotropic glutamate receptors. Furthermore, tetraethylammonium also evoked irregular discharges on dorsal roots. Rhythmic alternating patterns elicited by tetraethylammonium on ventral roots were relatively stereotypic, had limited synergy with fictive locomotion induced by dorsal root stimuli, and were not accelerated by 4-aminopyridine. Horizontal section of the spinal cord preserved irregular ventral root discharges and dorsal root discharges, demonstrating that the action of tetraethylammonium on spinal networks was fundamentally different from that of 4-aminopyridine. These results show that a potassium channel blocker such as tetraethylammonium could activate fictive locomotion in the rat isolated spinal cord, although the pattern quality lacked certain features like frequency modulation and strong synergy with other inputs to locomotor networks. PMID:16289841

Taccola, G; Nistri, A

2006-01-01

319

Neural Mechanisms Underlying the Generation of the Lobster Gastric Mill Motor Pattern  

PubMed Central

The lobster gastric mill central pattern generator (CPG) is located in the stomatogastric ganglion and consists of 11 neurons whose circuitry is well known. Because all of the neurons are identifiable and accessible, it can serve as a prime experimental model for analyzing how microcircuits generate multiphase oscillatory spatiotemporal patterns. The neurons that comprise the gastric mill CPG consist of one interneuron, five burster neurons and six tonically firing neurons. The single interneuron (Int 1) is shared by the medial tooth subcircuit (containing the AM, DG and GMs) and the lateral teeth subcircuit (LG, MG and LPGs). By surveying cell-to-cell connections and the cooperative dynamics of the neurons we find that the medial subcircuit is essentially a feed forward system of oscillators. The Int 1 neuron entrains the DG and AM cells by delayed excitation and this pair then periodically inhibits the tonically firing GMs causing them to burst. The lateral subcircuit consists of two negative feedback loops of reciprocal inhibition from Int 1 to the LG/MG pair and from the LG/MG to the LPGs. Following a fast inhibition from Int 1, the LG/MG neurons receive a slowly developing excitatory input similar to that which Int 1 puts onto DG/AM. Thus Int 1 plays a key role in synchronizing both subcircuits. This coordinating role is assisted by additional, weaker connections between the two subsets but those are not sufficient to synchronize them in the absence of Int 1. In addition to the experiments, we developed a conductance-based model of a slightly simplified gastric circuit. The mathematical model can reproduce the fundamental rhythm and many of the experimentally induced perturbations. Our findings shed light on the functional role of every cell and synapse in this small circuit providing a detailed understanding of the rhythm generation and pattern formation in the gastric mill network.

Selverston, Allen I.; Szucs, Attila; Huerta, Ramon; Pinto, Reynaldo; Reyes, Marcelo

2009-01-01

320

Precise colocalization of interacting structural and pigmentary elements generates extensive color pattern variation in Phelsuma lizards  

PubMed Central

Background Color traits in animals play crucial roles in thermoregulation, photoprotection, camouflage, and visual communication, and are amenable to objective quantification and modeling. However, the extensive variation in non-melanic pigments and structural colors in squamate reptiles has been largely disregarded. Here, we used an integrated approach to investigate the morphological basis and physical mechanisms generating variation in color traits in tropical day geckos of the genus Phelsuma. Results Combining histology, optics, mass spectrometry, and UV and Raman spectroscopy, we found that the extensive variation in color patterns within and among Phelsuma species is generated by complex interactions between, on the one hand, chromatophores containing yellow/red pteridine pigments and, on the other hand, iridophores producing structural color by constructive interference of light with guanine nanocrystals. More specifically, we show that 1) the hue of the vivid dorsolateral skin is modulated both by variation in geometry of structural, highly ordered narrowband reflectors, and by the presence of yellow pigments, and 2) that the reflectivity of the white belly and of dorsolateral pigmentary red marks, is increased by underlying structural disorganized broadband reflectors. Most importantly, these interactions require precise colocalization of yellow and red chromatophores with different types of iridophores, characterized by ordered and disordered nanocrystals, respectively. We validated these results through numerical simulations combining pigmentary components with a multilayer interferential optical model. Finally, we show that melanophores form dark lateral patterns but do not significantly contribute to variation in blue/green or red coloration, and that changes in the pH or redox state of pigments provide yet another source of color variation in squamates. Conclusions Precisely colocalized interacting pigmentary and structural elements generate extensive variation in lizard color patterns. Our results indicate the need to identify the developmental mechanisms responsible for the control of the size, shape, and orientation of nanocrystals, and the superposition of specific chromatophore types. This study opens up new perspectives on Phelsuma lizards as models in evolutionary developmental biology.

2013-01-01

321

Distinct inspiratory rhythm and pattern generating mechanisms in the preBötzinger complex.  

PubMed

In the mammalian respiratory central pattern generator, the preBötzinger complex (preBötC) produces rhythmic bursts that drive inspiratory motor output. Cellular mechanisms initiated by each burst are hypothesized to be necessary to determine the timing of the subsequent burst, playing a critical role in rhythmogenesis. To explore mechanisms relating inspiratory burst generation to rhythmogenesis, we compared preBötC and hypoglossal (XII) nerve motor activity in medullary slices from neonatal mice in conditions where periods between successive inspiratory XII bursts were highly variable and distributed multimodally. This pattern resulted from rhythmic preBötC neural population activity that consisted of bursts, concurrent with XII bursts, intermingled with significantly smaller "burstlets". Burstlets occurred at regular intervals during significantly longer XII interburst intervals, at times when a XII burst was expected. When a preBötC burst occurred, its high amplitude inspiratory component (I-burst) was preceded by a preinspiratory component that closely resembled the rising phase of burstlets. Cadmium (8 ?M) eliminated preBötC and XII bursts, but rhythmic preBötC burstlets persisted. Burstlets and preinspiratory activity were observed in ~90% of preBötC neurons that were active during I-bursts. When preBötC excitability was raised significantly, burstlets could leak through to motor output in medullary slices and in vivo in adult anesthetized rats. Thus, rhythmic bursting, a fundamental mode of nervous system activity and an essential element of breathing, can be deconstructed into a rhythmogenic process producing low amplitude burstlets and preinspiratory activity that determine timing, and a pattern-generating process producing suprathreshold I-bursts essential for motor output. PMID:23719793

Kam, Kaiwen; Worrell, Jason W; Janczewski, Wiktor A; Cui, Yan; Feldman, Jack L

2013-05-29

322

Distinct inspiratory rhythm and pattern generating mechanisms in the preB?tzinger Complex  

PubMed Central

In the mammalian respiratory central pattern generator, the preBötzinger Complex (preBötC) produces rhythmic bursts that drive inspiratory motor output. Cellular mechanisms initiated by each burst are hypothesized to be necessary to determine the timing of the subsequent burst, playing a critical role in rhythmogenesis. To explore mechanisms relating inspiratory burst generation to rhythmogenesis, we compared preBötC and hypoglossal (XII) nerve motor activity in medullary slices from neonatal mice in conditions where periods between successive inspiratory XII bursts were highly variable and distributed multimodally. This pattern resulted from rhythmic preBötC neural population activity that consisted of bursts, concurrent with XII bursts, intermingled with significantly smaller “burstlets”. Burstlets occurred at regular intervals during significantly longer XII interburst intervals, at times when a XII burst was expected. When a preBötC burst occurred, its high amplitude inspiratory component (I-burst) was preceded by a preinspiratory component that closely resembled the rising phase of burstlets. Cadmium (8 ?M) eliminated preBötC and XII bursts, but rhythmic preBötC burstlets persisted. Burstlets and preinspiratory activity were observed in ~90% of preBötC neurons that were active during I-bursts. When preBötC excitability was raised significantly, burstlets could leak through to motor output in medullary slices and in vivo in adult anesthetized rats. Thus, rhythmic bursting, a fundamental mode of nervous system activity and an essential element of breathing, can be deconstructed into a rhythmogenic process producing low amplitude burstlets and preinspiratory activity that determine timing, and a pattern-generating process producing suprathreshold I-bursts essential for motor output.

Kam, Kaiwen; Worrell, Jason W.; Janczewski, Wiktor A.; Cui, Yan; Feldman, Jack L.

2013-01-01

323

Mathematical study on ionic mechanism of lamprey central pattern generator model.  

PubMed

This paper studies the mechanisms of ionic channels in neurons of lamprey central pattern generator (CPG), such as the N-methyl-D-aspartate (NMDA) receptor channel and the calcium-dependent potassium channel etc. The CPG properties on oscillation attributed to the ionic mechanisms are exploited. The conditions for oscillation, divergence, convergence and the guidelines on selection of the parameters are established. The effects of key parameters on CPG frequency and duty cycle are investigated. Mathematical analysis and simulation study is performed to verify these results. This study will potentially enhance the effective application of biological CPG model into engineering practice such as robotics. PMID:20039464

Zhang, Dingguo; Zhu, Xiangyang; Lan, Li; Zhu, Kuanyi

2009-12-01

324

Effects of Glycinergic Inhibition Failure on Respiratory Rhythm and Pattern Generation  

PubMed Central

Inhibitory interactions between neurons of the respiratory network are involved in rhythm generation and pattern formation. Using a computational model of brainstem respiratory networks, we investigated the possible effects of suppressing glycinergic inhibition on the activity of different respiratory neuron types. Our study revealed that progressive suppression of glycinergic inhibition affected all neurons of the network and disturbed neural circuits involved in termination of inspiration. Causal was a dysfunction of postinspiratory inhibition targeting inspiratory neurons, which often led to irregular preterm reactivation of these neurons, producing double or multiple short-duration inspiratory bursts. An increasing blockade of glycinergic inhibition led to apneustic inspiratory activity. Similar disturbances of glycinergic inhibition also occur during hypoxia. A clear difference in prolonged hypoxia, however, is that the rhythm terminates in expiratory apnea. The critical function of glycinergic inhibition for normal respiratory rhythm generation and the consequences of its reduction, including in pathological conditions, are discussed.

Shevtsova, Natalia A.; Busselberg, Dietrich; Molkov, Yaroslav I.; Bischoff, Anne M.; Smith, Jeffrey C.; Richter, Diethelm W.; Rybak, Ilya A.

2014-01-01

325

The internal flow pattern analysis of a tidal power turbine operating on bidirectional generation-pumping  

NASA Astrophysics Data System (ADS)

Using tidal energy can reduce environment pollution, save conventional energy and improve energy structure, hence it presents great advantage and is developing potential. Influenced by flood tide and low tide, a fully functional tidal power station needs to experience six operating modes, including bidirectional generation, pumping and sluice; the internal unsteady flow pattern and dynamic characters are very complicated. Based on a bidirectional tidal generator unit, three-dimensional unsteady flows in the flow path were calculated for four typical operating conditions with the pressure pulsation characteristics analyzed. According to the numerical results, the internal flow characteristics in the flow path were discussed. The influence of gravity to the hydraulic performance and flow characteristics were analysed. The results provide a theoretical analysis method of the hydraulic optimization design of the same type unit as well as a direction for stable operation and optimal scheduling of existing tidal power unit.

Y Luo, Y.; Xiao, Y. X.; Wang, Z. W.

2013-12-01

326

The use of hierarchy in test generation, fault simulation, and testability analysis algorithms  

SciTech Connect

In digital-circuit design, two activities are extraordinarily compute-intensive: fault simulation and automatic test pattern generation. Historically, since design was done on a single level, simulators and other design tools evolved for single-level circuits. More recent design techniques have incorporated hierarchical methodologies, but the design tools have not followed by exploiting this hierarchy. This thesis extends prior work by incorporating the design hierarchy into a fault simulator and exploiting the hierarchy to achieve improved simulator performance. The hierarchical fault simulator developed in this work is named CHIEFS, which stands for concurrent hierarchical and extensible fault simulator. It is unique in that it stimulates directly from the hierarchical circuit description without flattening the circuit to a single level. In contrast to CHIEFS, which uses the circuit hierarchy for partitioning, HAT, which stands for heuristic adviser for testability, uses the circuit-design hierarchy as contextual information. A hierarchical test generation approach, named SHAMAN, is presented that promises significantly reduce the computation requirements for test generation with mechanisms similar to those demonstrated for fault simulation in CHIEFS.

Rogers, W.A.

1988-01-01

327

NIH Toolbox Cognitive Battery (NIHTB-CB): The NIHTB Pattern Comparison Processing Speed Test.  

PubMed

The NIH Toolbox (NIHTB) Pattern Comparison Processing Speed Test was developed to assess processing speed within the NIHTB for the Assessment of Neurological Behavior and Function Cognition Battery (NIHTB-CB). This study highlights validation data collected in adults ages 18-85 on this measure and reports descriptive data, test-retest reliability, construct validity, and preliminary work creating a composite index of processing speed. Results indicated good test-retest reliability. There was also evidence for both convergent and discriminant validity; the Pattern Comparison Processing Speed Test demonstrated moderate significant correlations with other processing speed tests (i.e., WAIS-IV Coding, Symbol Search and Processing Speed Index), small significant correlations with measures of working memory (i.e., WAIS-IV Letter-Number Sequencing and PASAT), and non-significant correlations with a test of vocabulary comprehension (i.e., PPVT-IV). Finally, analyses comparing and combining scores on the NIHTB Pattern Comparison Processing Speed Test with other measures of simple reaction time from the NIHTB-CB indicated that a Processing Speed Composite score performed better than any test examined in isolation. The NIHTB Pattern Comparison Processing Speed Test exhibits several strengths: it is appropriate for use across the lifespan (ages, 3-85 years), it is short and easy to administer, and it has high construct validity. (JINS, 2014, 20, 1-12). PMID:24960594

Carlozzi, Noelle E; Tulsky, David S; Chiaravalloti, Nancy D; Beaumont, Jennifer L; Weintraub, Sandra; Conway, Kevin; Gershon, Richard C

2014-07-01

328

Ballerina: Automatic generation and clustering of efficient random unit tests for multithreaded code  

Microsoft Academic Search

Testing multithreaded code is hard and expensive. A multithreaded unit test creates two or more threads, each executing one or more methods on shared objects of the class under test. Such unit tests can be generated at random, but basic random generation produces tests that are either slow or do not trigger concurrency bugs. Worse, such tests have many false

Adrian Nistor; Qingzhou Luo; Michael Pradel; Thomas R. Gross; Darko Marinov

2012-01-01

329

TESTING OF THE SECOND GENERATION SPINTEK ROTARY FILTER -11357  

SciTech Connect

The SpinTek rotary microfilter has been developed under the Department of Energy (DOE) Office of Environmental Management (EM) for the purpose of deployment in radioactive service in the DOE complex. The unit that was fabricated and tested is the second generation of the filter that incorporates recommended improvements from previous testing. The completion of this test satisfied a key milestone for the EM technology development program and technology readiness for deployment by Savannah River Remediation in the Small Column Ion Exchange and Sludge Washing processes at the Savannah River Site (SRS). The Savannah River National Laboratory (SRNL) contracted SpinTek Filtration to fabricate a full scale 25 disk rotary filter and perform a 1000 hour endurance test with a simulated SRS sludge. Over 1500 hours of operation have been completed with the filter. SpinTek Filtration fabricated a prototypic 25 disk rotary filter including updates to manufacturing tolerances, an updated design to the rotary joint, improved cooling to the bottom journal, decreases in disk and filter shaft hydraulic resistances. The filter disks were fabricated with 0.5 {micro} pore size, sintered-metal filter media manufactured by Pall Corporation (M050). After fabrication was complete, the filter passed acceptance tests demonstrating rejection of solids and clean water flux with a 50% improvement over the previous filters. Once the acceptance test was complete, a 1000 hour endurance test was initiated simulating a sludge washing process. The test used a simulated SRS Sludge Batch 6 recipe. The insoluble solids started at 5 wt% and were raised to 10 and 15 wt% insoluble solids to simulate the concentration of a large volume tank. The filter system was automated and set up for 24 hour unattended operation. To facilitate this, process control logic was written to operate the filter. During the development it was demonstrated that the method of starting and stopping the filter can affect the build up of filter cake on the disks and therefore the performance of the filter. The filter performed well with the simulant. Very little drop in production was noticed between the 5 and 10 wt% insoluble solids feed. Increasing to 15 wt% had a more pronounced impact due to the rheology of the feed. Acid cleaning was used to clean the filter disks in-situ and restore filtration rate to almost 90% of the initial clean disk rate. Eighty liters of 0.2 M nitric acid in conjunction with water rinses were used to clean the filter in less than 2 hours. Filter testing was completed after 1000 hours of operation were performed on the final filter assembly configuration. The total run time for the testing was over 1500 hours. At the end of the test, the sludge washing was performed successfully from approximately 5.6 M to less than 1 M sodium.

Herman, D.; Poirier, M.; Fowley, M.; Keefer, M.; Huff, T.

2011-02-02

330

An Experimental and Theoretical Study of Fracture Patterns Generated by Underground Explosions  

NASA Astrophysics Data System (ADS)

A dynamic micro-mechanical damage mechanics model, developed by Bhat, Rosakis and Sammis, J. Appl. Mech., 2012, is used to simulate two-dimensional explosions in a brittle material. The theoretical patterns of circumferential and radial fractures are quantitatively compared with those produced by point explosions in very brittle "candy glass" plates. In these experiments the evolution of the fracture pattern is monitored using high-speed digital photography, which also images the resultant elastic waves (P and S). Theoretical estimates of the spatial extent of circumferential and radial cracking as well as the propagation speed of the comminution front and the growth-rate of individual radial cracks all compare well with the experimental observations. The wave-forms of the P and S waves, specifically the local particle velocities, are also recorded at selected points using laser vibrometers. Asymmetric fracture patterns caused by a non isotropic pre-stress, the preferred orientation of initial flaws (a rift plane), or a lithostatic gradient lead to the generation of strong S-waves from the otherwise spherically symmetric point source.

Bhat, H.; Mihaly, J. M.; Rosakis, A.; Sammis, C. G.

2012-12-01

331

Fast oscillations during gasping and other non-eupneic respiratory behaviors: Clues to central pattern generation.  

PubMed

The mammalian nervous system exhibits fast synchronous oscillations, which are especially prominent in respiratory-related nerve discharges. In the phrenic nerve, they include high- (HFO), medium- (MFO), and low-frequency (LFO) oscillations. Because motoneurons firing at HFO-related frequencies had never been recorded, an epiphenomenological mechanism for their existence had been posited. We have recently recorded phrenic motoneurons firing at HFO-related frequencies in unanesthetized decerebrate rats and showed that they exhibit dynamic coherence with the phrenic nerve, validating synchronous motoneuronal discharge as a mechanism underlying the generation of HFO. In so doing, we have helped validate the conclusions of previous studies by us and other investigators who have used changes in fast respiratory oscillations to make inferences about central respiratory pattern generation. Here, we seek to review changes occurring in fast synchronous oscillations during non-eupneic respiratory behaviors, with special emphasis on gasping, and the inferences that can be drawn from these dynamics regarding respiratory pattern formation. PMID:23545119

Ghali, Michael George Zaki; Marchenko, Vitaliy

2013-06-15

332

Resolution improvement and pattern generator development for the maskless micro-ion-beam reduction lithography system  

NASA Astrophysics Data System (ADS)

The shrinking of IC devices has followed the Moore's Law for over three decades, which states that the density of transistors on integrated circuits will double about every two years. This great achievement is obtained via continuous advance in lithography technology. With the adoption of complicated resolution enhancement technologies, such as the phase shifting mask (PSM), the optical proximity correction (OPC), optical lithography with wavelength of 193 nm has enabled 45 nm printing by immersion method. However, this achievement comes together with the skyrocketing cost of masks, which makes the production of low volume application-specific IC (ASIC) impractical. In order to provide an economical lithography approach for low to medium volume advanced IC fabrication, a maskless ion beam lithography method, called Maskless Micro-ion-beam Reduction Lithography (MMRL), has been developed in the Lawrence Berkeley National Laboratory. The development of the prototype MMRL system has been described by Dr. Vinh Van Ngo in his Ph.D. thesis. But the resolution realized on the prototype MMRL system was far from the design expectation. In order to improve the resolution of the MMRL system, the ion optical system has been investigated. By integrating a field-free limiting aperture into the optical column, reducing the electromagnetic interference and cleaning the RF plasma, the resolution has been improved to around 50 nm. Computational analysis indicates that the MMRL system can be operated with an exposure field size of 0.25 mm and a beam half angle of 1.0 mrad on the wafer plane. Ion-ion interactions have been studied with a two-particle physics model. The results are in excellent agreement with those published by the other research groups. The charge-interaction analysis of MMRL shows that the ion-ion interactions must be reduced in order to obtain a throughput higher than 10 wafers per hour on 300-mm wafers. In addition, two different maskless lithography strategies have been studied. The dependence of the throughput with the exposure field size and the speed of the mechanical stage has been investigated. In order to perform maskless lithography, different micro-fabricated pattern generators have been developed for the MMRL system. Ion beamlet switching has been successfully demonstrated on the MMRL system. A positive bias voltage around 10 volts is sufficient to switch off the ion current on the micro-fabricated pattern generators. Some unexpected problems, such as the high-energy secondary electron radiations, have been discovered during the experimental investigation. Thermal and structural analysis indicates that the aperture displacement error induced by thermal expansion can satisfy the 3delta CD requirement for lithography nodes down to 25 nm. The cross-talking effect near the surface and inside the apertures of the pattern generator has been simulated in a 3-D ray-tracing code. New pattern generator design has been proposed to reduce the cross-talking effect. In order to eliminate the surface charging effect caused by the secondary electrons, a new beam-switching scheme in which the switching electrodes are immersed in the plasma has been demonstrated on a mechanically fabricated pattern generator.

Jiang, Ximan

333

Mining Frequent Patterns from Software Defect Repositories for BlackBox Testing  

Microsoft Academic Search

Software defects are usually detected by inspection, black-box testing or white-box testing. Current software defect mining work focuses on mining frequent patterns without distinguishing these different kinds of defects, and mining with respect to defect type can only give limited guidance on software development due to overly broad classification of defect type. In this paper, we present four kinds of

Ning Li; Zhanhuai Li; Lijun Zhang

2010-01-01

334

3D CAD model generation of mechanical parts using coded-pattern projection and laser triangulation systems  

Microsoft Academic Search

Purpose – Investigate the use of two imaging-based methods – coded pattern projection and laser-based triangulation – to generate 3D models as input to a rapid prototyping pipeline. Design\\/methodology\\/approach – Discusses structured lighting technologies as suitable imaging-based methods. Two approaches, coded-pattern projection and laser-based triangulation, are specifically identified and discussed in detail. Two commercial systems are used to generate experimental

David Page; Andreas Koschan; Sophie Voisin; Ngozi Ali; Mongi Abidi

2005-01-01

335

Airborne molecular contamination control in the micromirror SLM-based deep ultraviolet DUV SIGMA7300 laser pattern generator  

Microsoft Academic Search

Airborne molecular contamination (AMC) in the form of bases, acids and condensable organic and inorganic substances threaten both costly and sensitive optics and mask pattern formation in the chemically amplified resists (CAR) used for both E-beam and laser lithography. This is particularly so for mask pattern generators due to the relatively long writing times. In the development work of the

Mats Ekberg; Hans A. Fosshaug; Thomas Ostrom; Peter Bjornangen; Thomas Utterback; Per-Uno Skotte; John Higley; David Ruede; Oleg P. Kishkovich

2004-01-01

336

Entropy Generation/Availability Energy Loss Analysis Inside MIT Gas Spring and "Two Space" Test Rigs  

NASA Technical Reports Server (NTRS)

The results of the entropy generation and availability energy loss analysis under conditions of oscillating pressure and oscillating helium gas flow in two Massachusetts Institute of Technology (MIT) test rigs piston-cylinder and piston-cylinder-heat exchanger are presented. Two solution domains, the gas spring (single-space) in the piston-cylinder test rig and the gas spring + heat exchanger (two-space) in the piston-cylinder-heat exchanger test rig are of interest. Sage and CFD-ACE+ commercial numerical codes are used to obtain 1-D and 2-D computer models, respectively, of each of the two solution domains and to simulate the oscillating gas flow and heat transfer effects in these domains. Second law analysis is used to characterize the entropy generation and availability energy losses inside the two solution domains. Internal and external entropy generation and availability energy loss results predicted by Sage and CFD-ACE+ are compared. Thermodynamic loss analysis of simple systems such as the MIT test rigs are often useful to understand some important features of complex pattern forming processes in more complex systems like the Stirling engine. This study is aimed at improving numerical codes for the prediction of thermodynamic losses via the development of a loss post-processor. The incorporation of loss post-processors in Stirling engine numerical codes will facilitate Stirling engine performance optimization. Loss analysis using entropy-generation rates due to heat and fluid flow is a relatively new technique for assessing component performance. It offers a deep insight into the flow phenomena, allows a more exact calculation of losses than is possible with traditional means involving the application of loss correlations and provides an effective tool for improving component and overall system performance.

Ebiana, Asuquo B.; Savadekar, Rupesh T.; Patel, Kaushal V.

2006-01-01

337

Test-Quality\\/Cost Optimization Using Output-Deviation-Based Reordering of Test Patterns  

Microsoft Academic Search

At-speed functional testing, delay testing, and n-detection test sets are being used today to detect deep submi- crometer defects. However, the resulting test data volumes are too high; the 2005 International Roadmap for Semiconductors predicts that test-application times will be 30 times larger in 2010 than they are today. In addition, many new types of defects cannot be accurately modeled

Zhanglei Wang; Krishnendu Chakrabarty

2008-01-01

338

Augmenting Automatically Generated Unit-Test Suites with Regression Oracle Checking  

Microsoft Academic Search

A test case consists of two parts: a test input to exercise the program under test and a test oracle to check the correctness of the test execution. A test oracle is often in the form of executable assertions such as in the JUnit test- ing framework. Manually generated test cases are valuable in exposing program faults in the current

Tao Xie

2006-01-01

339

Tests of Micro-Pattern Gaseous Detectors for active target time projection chambers in nuclear physics  

NASA Astrophysics Data System (ADS)

Active target detection systems, where the gas used as the detection medium is also a target for nuclear reactions, have been used for a wide variety of nuclear physics applications since the eighties. Improvements in Micro-Pattern Gaseous Detectors (MPGDs) and in micro-electronics achieved in the last decade permit the development of a new generation of active targets with higher granularity pad planes that allow spatial and time information to be determined with unprecedented accuracy. A novel active target and time projection chamber (ACTAR TPC), that will be used to study reactions and decays of exotic nuclei at facilities such as SPIRAL2, is presently under development and will be based on MPGD technology. Several MPGDs (Micromegas and Thick GEM) coupled to a 2×2 mm2 pixelated pad plane have been tested and their performances have been determined with different gases over a wide range of pressures. Of particular interest for nuclear physics experiments are the angular and energy resolutions. The angular resolution has been determined to be better than 1° FWHM for short traces of about 4 cm in length and the energy resolution deduced from the particle range was found to be better than 5% for 5.5 MeV ? particles. These performances have been compared to Geant4 simulations. These experimental results validate the use of these detectors for several applications in nuclear physics.

Pancin, J.; Damoy, S.; Perez Loureiro, D.; Chambert, V.; Dorangeville, F.; Druillole, F.; Grinyer, G. F.; Lermitage, A.; Maroni, A.; Noël, G.; Porte, C.; Roger, T.; Rosier, P.; Suen, L.

2014-01-01

340

Artificial neural network model for the generation of muscle activation patterns for human locomotion.  

PubMed

Skilled locomotor behaviour requires information from various levels within the central nervous system (CNS). Mathematical models have permitted researchers to simulate various mechanisms in order to understand the organization of the locomotor control system. While it is difficult to adequately characterize the numerous inputs to the locomotor control system, an alternative strategy may be to use a kinematic movement plan to represent the complex inputs to the locomotor control system based on the possibility that the CNS may plan movements at a kinematic level. We propose the use of artificial neural network (ANN) models to represent the transformation of a kinematic plan into the necessary motor patterns. Essentially, kinematic representation of the actual limb movement was used as the input to an ANN model which generated the EMG activity of 8 muscles of the lower limb and trunk. Data from a wide variety of gait conditions was necessary to develop a robust model that could accommodate various environmental conditions encountered during everyday activity. A total of 120 walking strides representing normal walking and ten conditions where the normal gait was modified in terms of cadence, stride length, stance width or required foot clearance. The final network was assessed on its ability to predict the EMG activity on individual walking trials as well as its ability to represent the general activation pattern of a particular gait condition. The predicted EMG patterns closely matched those recorded experimentally, exhibiting the appropriate magnitude and temporal phasing required for each modification. Only 2 of the 96 muscle/gait conditions had RMS errors above 0.10, only 5 muscle/gait conditions exhibited correlations below 0.80 (most were above 0.90) and only 25 muscle/gait conditions deviated outside the normal range of muscle activity for more than 25% of the gait cycle. These results indicate the ability of single network ANNs to represent the transformation between a kinematic movement plan and the necessary muscle activations for normal steady state locomotion but they were also able to generate muscle activation patterns for conditions requiring changes in walking speed, foot placement and foot clearance. The abilities of this type of network have implications towards both the fundamental understanding of the control of locomotion and practical realizations of artificial control systems for use in rehabilitation medicine. PMID:11166605

Prentice, S D; Patla, A E; Stacey, D A

2001-02-01

341

GENERIC VERIFICATION PROTOCOL: DISTRIBUTED GENERATION AND COMBINED HEAT AND POWER FIELD TESTING PROTOCOL  

EPA Science Inventory

This report is a generic verification protocol by which EPA?s Environmental Technology Verification program tests newly developed equipment for distributed generation of electric power, usually micro-turbine generators and internal combustion engine generators. The protocol will ...

342

Automated model based software Test Data Generation System  

Microsoft Academic Search

Testing is an important construct of software development lifecycle. It validates that the application under test is doing exactly what it was developed for. In other words, testing ensures the reliability of software. On contrarily, testing is the most difficult, time consuming and costly construct of software development, where as test data is the back bone of testing because it

Muhammad Farhan Bashir; S. H. K. Banuri

2008-01-01

343

Double patterning for 56 nm pitch test designs using inverse lithography  

NASA Astrophysics Data System (ADS)

The ITRS roadmap1 lists double patterning 193 nm immersion exposure with inverse lithography as the likely solution through the 22 nm half pitch generation. Three different patterns, scaled to 56 nm pitch, were explored using inverse lithography.2,3 The patterns are a trim mask design adapted from Schenker, et al.4, a bit line design published by Pyo, et al.5 and a metal layer design published by Lucas, et al.6. A free form gray scale illuminator was determined for each pattern. Good results were obtained for the trim mask design with a process variation of less than 8 nm for 50 nm of defocus and MEEF less than 6. The bit line design had to be modified from the published version which increased the pattern area by 18.8%. For this pattern there was a maximum process variation of 11 nm for 50 nm of defocus and MEEF less than 14. The metal layer design had to be modified which increased the pattern area by 2.6%. With these changes there was a maximum process variation of 8.4 nm for 50 nm of defocus and MEEF less than 7.

Dam, Thuc; Gleason, Robert; Rissman, Paul; Sinn, Robert

2011-10-01

344

The Hyper-X Antenna Radiation Pattern Tests and Radio Frequency System Redesign  

NASA Technical Reports Server (NTRS)

Testing was performed to determine the antenna radiation pattern measurements of the Hyper-X, X-43 ship 2 aircraft. One test was conducted at the Air Force Flight Test Center (AFFTC) Benefield Anechoic Facility (BAF) on January 24-January 27, 2000. A second test was done at MicroCraft in Tullahoma Tennessee by the Naval Air Weapons Center (NAWC) China Lake, California on September 8, 2001. The overall test objective was to gather qualitative antenna radiation pattern data from installed antennas on the HXRV. This objective was accomplished by collecting antenna radiation patterns at selected elevations of the HXRV. The test data was used to identify areas of RF coverage and assist in positioning the P-3 aircraft for best RF reception. The antenna pattern data presented nulls and possible low RF reception areas around the aircraft. This led to a redesign of the RF system. The redesigned system provided redundancy in case a telemetry transmitter should fail. The redesign provided more complete RF coverage within the antenna's capabilities. A second look at the flight path and necessary data collection led to a change in the beacon transponder system.

Hodge, Mark W.; Kelley, John W.

2006-01-01

345

Airborne molecular contamination control in the micromirror SLM-based deep ultraviolet DUV SIGMA7300 laser pattern generator  

NASA Astrophysics Data System (ADS)

Airborne molecular contamination (AMC) in the form of bases, acids and condensable organic and inorganic substances threaten both costly and sensitive optics and mask pattern formation in the chemically amplified resists (CAR) used for both E-beam and laser lithography. This is particularly so for mask pattern generators due to the relatively long writing times. In the development work of the SLM-based DUV-laser mask pattern generator Sigma7300, AMC aspects have been taken into consideration from an early stage. That includes e.g. analysis and selection of construction materials and development of handling methods as well as application of chemical filtering systems. Tool manufacturer and filter supplier have together specified and designed efficient hybrid filtration systems for use in Sigma7300. This paper describes AMC aspects specific for mask pattern generators, the successful design actions of the Sigma7300 and verifying analyses of the processes.

Ekberg, Mats; Fosshaug, Hans A.; Ostrom, Thomas; Bjornangen, Peter; Utterback, Thomas; Skotte, Per-Uno; Higley, John; Ruede, David; Kishkovich, Oleg P.

2004-05-01

346

HIV Testing Patterns among Black Men Who Have Sex with Men: A Qualitative Typology  

PubMed Central

Background Black men who have sex with men (MSM) in the Southeastern United States are disproportionately affected by HIV. Black MSM are more likely to have unrecognized HIV infection, suggesting that testing may occur later and/or infrequently relative to current recommendations. The objective of this qualitative study was to explore the HIV testing behaviors of Black MSM in Atlanta, Georgia, who were participants in the HIV Prevention Trials Network Brothers Study (HPTN 061). Methods and Findings We conducted 29 in-depth interviews and four focus groups with a community-recruited sample. Modified grounded theory methodologies were used to guide our inductive analysis, which yielded a typology comprised of four distinct HIV testing patterns. Participants could be categorized as: (1) Maintenance Testers, who tested regularly as part of routine self-care; (2) Risk-Based Testers, whose testing depended on relationship status or sexual behavior; (3) Convenience Testers, who tested irregularly depending on what testing opportunities arose; or (4) Test Avoiders, who tested infrequently and/or failed to follow up on results. We further characterized these groups with respect to age, socioeconomic factors, identity, stigma and healthcare access. Conclusions Our findings highlight the heterogeneity of HIV testing patterns among Black MSM, and offer a framework for conceptualizing HIV testing in this group. Public health messaging must account for the diversity of Black MSM's experiences, and multiple testing approaches should be developed and utilized to maximize outreach to different types of testers.

Hussen, Sophia A.; Stephenson, Robert; del Rio, Carlos; Wilton, Leo; Wallace, Jermel; Wheeler, Darrell

2013-01-01

347

Reification of Executable Test Scripts in Formal Specicifation-Based Test Generation: The Java Card Transaction Mechanism Case Study  

Microsoft Academic Search

\\u000a Automatic generation of test cases from formal specification is a very promising way both to give a rationale for deciding\\u000a the scope of testing and to reduce the time for test design and coding. In order to achieve this purpose, formal specification-based\\u000a methods must solve the problem of executable test script generation from abstract test cases and automatic verdict assignment.

Fabrice Bouquet; Bruno Legeard

2003-01-01

348

Reticular activating system of a central pattern generator: premovement electrical potentials  

PubMed Central

For the first time, here we characterize a bulbar reticular activating system (RAS) of neurons in decerebrate, deafferented and decerebellated cats producing a premovement electrical potential that we named obex slow potential (OSP). The OSP occurs about 0.8 ± 0.4 sec prior to the onset of a fictive-scratching-episode. Here, we describe two classes of bulbar neurons, off-on, which are silent but exhibit a 80 ± 56 Hz firing discharge at the beginning of (and during) the OSP, and on-off interneurons, with a 27 ± 14 Hz firing activity that stops at the beginning of (and during) the OSP. We suggest that these OSP-associated neurons belong to a descending RAS, which contributes to the activation of the spinal central pattern generators.

Tapia, Jesus A; Trejo, Argelia; Linares, Pablo; Alva, J Manuel; Kristeva, Rumyana; Manjarrez, Elias

2013-01-01

349

A new Pulse-Pattern Generator based on LabVIEW FPGA  

NASA Astrophysics Data System (ADS)

For the control of experimental sequences composed of triggers, gates and delays a Pulse-Pattern Generator (PPG) has been developed based on a Field Programmable Gate Array (FPGA) addressed in a LabVIEW environment. It allows a highly reproducible timing of measurement procedures by up to 64 individual channels with pulse and delay periods from the nanoseconds to the minutes range. The PPG has been implemented in the context of the development of a new control system for the ClusterTrap setup, an ion storage device for atomic-cluster research, in close contact with the SHIPTRAP and ISOLTRAP collaborations at GSI and CERN, respectively. As the new PPG is not ion-trap specific it can be employed in any experiment based on sequences of triggers, pulses and delays.

Ziegler, F.; Beck, D.; Brand, H.; Hahn, H.; Marx, G.; Schweikhard, L.

2012-07-01

350

Photolithographic patterning of organosilane monolayer for generating large area two-dimensional B lymphocyte arrays†  

PubMed Central

High-density live cell array serves as a valuable tool for the development of high-throughput immunophenotyping systems and cell-based biosensors. In this paper, we have, for the first time, demonstrated a simple fabrication process to form the hexamethyldisilazane (HMDS) and poly(ethylene glycol) (PEG) binary molecular surface which can be used to effectively form high fidelity cell arrays. The HMDS self-assembled monolayer (SAM) on glass substrates was photolithographically patterned and its ability to physically adsorb proteins was characterized by contact angle measurement and fluorescence microscopy respectively. Passivation of the non-HMDS coated background by PEG was verified to have no impact on the pre-patterned HMDS and greatly inhibited the non-specific protein binding. Using the biotin–streptavidin complexation as an intermediate, uniform orientation and high bioactivity were achieved for the immobilized B lymphocyte specific anti-CD19 antibodies and therefore ensured the formation of high resolution B lymphocyte arrays. The cell–ligand interaction specificity was investigated and the anti-CD19 decorated micropatterns presented a much higher cell-capturing rate (88%) than those modified by non-specific ligands (15% for anti-CD5 and 7% for streptavidin). The approach was verified to be biocompatible and the properties of the antibody-modified surface were maintained after 12 h cell culture. The HMDS monolayer formation and patterning processes, and the universal HMDS/biotin-BSA/streptavidin template, provide a very simple and convenient process to generate high resolution micropatterns of cell-adhesive ligands and are extendable to form arrays of other types of cells as well.

Li, Nan

2009-01-01

351

Photolithographic patterning of organosilane monolayer for generating large area two-dimensional B lymphocyte arrays.  

PubMed

High-density live cell array serves as a valuable tool for the development of high-throughput immunophenotyping systems and cell-based biosensors. In this paper, we have, for the first time, demonstrated a simple fabrication process to form the hexamethyldisilazane (HMDS) and poly(ethylene glycol) (PEG) binary molecular surface which can be used to effectively form high fidelity cell arrays. The HMDS self-assembled monolayer (SAM) on glass substrates was photolithographically patterned and its ability to physically adsorb proteins was characterized by contact angle measurement and fluorescence microscopy respectively. Passivation of the non-HMDS coated background by PEG was verified to have no impact on the pre-patterned HMDS and greatly inhibited the non-specific protein binding. Using the biotin-streptavidin complexation as an intermediate, uniform orientation and high bioactivity were achieved for the immobilized B lymphocyte specific anti-CD19 antibodies and therefore ensured the formation of high resolution B lymphocyte arrays. The cell-ligand interaction specificity was investigated and the anti-CD19 decorated micropatterns presented a much higher cell-capturing rate (88%) than those modified by non-specific ligands (15% for anti-CD5 and 7% for streptavidin). The approach was verified to be biocompatible and the properties of the antibody-modified surface were maintained after 12 h cell culture. The HMDS monolayer formation and patterning processes, and the universal HMDS/biotin-BSA/streptavidin template, provide a very simple and convenient process to generate high resolution micropatterns of cell-adhesive ligands and are extendable to form arrays of other types of cells as well. PMID:19023473

Li, Nan; Ho, Chih-Ming

2008-12-01

352

Testing of the Mark 101 Magnetic Flux Compression Generator.  

National Technical Information Service (NTIS)

The Mark 101 explosive flux compression generator is a line-initiated, vacuum/magnetically insulated, helical generator. This device offered some unique challenges in transforming the theoretical design into a testable experiment. The two main reasons for...

B. L. Freeman C. M. Fowler J. C. King A. R. Martinez

1986-01-01

353

A connectionist central pattern generator for the aquatic and terrestrial gaits of a simulated salamander.  

PubMed

This article investigates the neural mechanisms underlying salamander locomotion, and develops a biologically plausible connectionist model of a central pattern generator capable of producing the typical aquatic and terrestrial gaits of the salamander. It investigates, in particular, what type of neural circuitry can produce and modulate the two locomotor programs identified within the salamander's spinal cord; namely, a traveling wave of neural activity for swimming and a standing wave for trotting. A two-dimensional biomechanical simulation of the salamander's body is developed whose muscle contraction is determined by the locomotion controller simulated as a leaky-integrator neural network. While the connectivity of the neural circuitry underlying locomotion in the salamander has not been decoded for the moment, this article presents the design of a neural circuit that has a general organization corresponding to that hypothesized by neurobiologists. In particular, the locomotion controller is based on a body central pattern generator (CPG) corresponding to a lamprey-like swimming controller, and is extended with a limb CPG for controlling the salamander's limbs. The complete controller is developed in three stages: first the development of segmental oscillators, second the development of intersegmental coupling for the making of a lamprey-like swimming CPG, and finally the development of the limb CPG and its coupling to the body CPG. A genetic algorithm is used to determine the parameters of the neural circuit for the different stages, given a high-level description of the desired state space trajectories of the different subnetworks. A controller is thus developed that can produce neural activities and locomotion gaits very similar to those observed in the real salamander. By varying the tonic (i.e. non-oscillating) excitation applied to the network, the speed, direction and type of gait can be varied. PMID:11357547

Ijspeert, A J

2001-05-01

354

Biological oscillations for learning walking coordination: dynamic recurrent neural network functionally models physiological central pattern generator  

PubMed Central

The existence of dedicated neuronal modules such as those organized in the cerebral cortex, thalamus, basal ganglia, cerebellum, or spinal cord raises the question of how these functional modules are coordinated for appropriate motor behavior. Study of human locomotion offers an interesting field for addressing this central question. The coordination of the elevation of the 3 leg segments under a planar covariation rule (Borghese et al., 1996) was recently modeled (Barliya et al., 2009) by phase-adjusted simple oscillators shedding new light on the understanding of the central pattern generator (CPG) processing relevant oscillation signals. We describe the use of a dynamic recurrent neural network (DRNN) mimicking the natural oscillatory behavior of human locomotion for reproducing the planar covariation rule in both legs at different walking speeds. Neural network learning was based on sinusoid signals integrating frequency and amplitude features of the first three harmonics of the sagittal elevation angles of the thigh, shank, and foot of each lower limb. We verified the biological plausibility of the neural networks. Best results were obtained with oscillations extracted from the first three harmonics in comparison to oscillations outside the harmonic frequency peaks. Physiological replication steadily increased with the number of neuronal units from 1 to 80, where similarity index reached 0.99. Analysis of synaptic weighting showed that the proportion of inhibitory connections consistently increased with the number of neuronal units in the DRNN. This emerging property in the artificial neural networks resonates with recent advances in neurophysiology of inhibitory neurons that are involved in central nervous system oscillatory activities. The main message of this study is that this type of DRNN may offer a useful model of physiological central pattern generator for gaining insights in basic research and developing clinical applications.

Hoellinger, Thomas; Petieau, Mathieu; Duvinage, Matthieu; Castermans, Thierry; Seetharaman, Karthik; Cebolla, Ana-Maria; Bengoetxea, Ana; Ivanenko, Yuri; Dan, Bernard; Cheron, Guy

2013-01-01

355

Directed functional connectivity matures with motor learning in a cortical pattern generator  

PubMed Central

Sequential motor skills may be encoded by feedforward networks that consist of groups of neurons that fire in sequence (Abeles 1991; Long et al. 2010). However, there has been no evidence of an anatomic map of activation sequence in motor control circuits, which would be potentially detectable as directed functional connectivity of coactive neuron groups. The proposed pattern generator for birdsong, the HVC (Long and Fee 2008; Vu et al. 1994), contains axons that are preferentially oriented in the rostrocaudal axis (Nottebohm et al. 1982; Stauffer et al. 2012). We used four-tetrode recordings to assess the activity of ensembles of single neurons along the rostrocaudal HVC axis in anesthetized zebra finches. We found an axial, polarized neural network in which sequential activity is directionally organized along the rostrocaudal axis in adult males, who produce a stereotyped song. Principal neurons fired in rostrocaudal order and with interneurons that were rostral to them, suggesting that groups of excitatory neurons fire at the leading edge of travelling waves of inhibition. Consistent with the synchronization of neurons by caudally travelling waves of inhibition, the activity of interneurons was more coherent in the orthogonal mediolateral axis than in the rostrocaudal axis. If directed functional connectivity within the HVC is important for stereotyped, learned song, then it may be lacking in juveniles, which sing a highly variable song. Indeed, we found little evidence for network directionality in juveniles. These data indicate that a functionally directed network within the HVC matures during sensorimotor learning and may underlie vocal patterning.

Day, Nancy F.; Terleski, Kyle L.; Nykamp, Duane Q.

2013-01-01

356

Wave patterns generated by an axisymmetric obstacle in a two-layer flow  

NASA Astrophysics Data System (ADS)

Gravity waves generated by a moving obstacle in a two-layer stratified fluid are investigated. The experimental configuration is three-dimensional with an axisymmetric obstacle which is towed in one of the two layers. The experimental method used in the present study is based on a stereoscopic technique allowing the 3D reconstruction of the interface between the two layers. Investigation into the wave pattern as a function of the Froude number, Fr, based on the relative density of the fluid layers and the velocity of the towed obstacle is presented. Specific attention is paid to the transcritical regime for which Fr is close to one. Potential energy trapped in the wave field patterns is also extracted from the experimental results and is analyzed as a function of both the Froude number, Fr, and the transcritical similarity parameter . In particular, a remarkable increase in the potential energy around Fr = 1 is observed and a scaling allowing to assemble data resulting from different experimental parameters is proposed.

Lacaze, L.; Paci, A.; Cid, E.; Cazin, S.; Eiff, O.; Esler, J. G.; Johnson, E. R.

2013-12-01

357

Overlapping gene coexpression patterns in human medullary thymic epithelial cells generate self-antigen diversity  

PubMed Central

Promiscuous expression of numerous tissue-restricted self-antigens (TRAs) in medullary thymic epithelial cells (mTECs) is essential to safeguard self-tolerance. A distinct feature of promiscuous gene expression is its mosaic pattern (i.e., at a given time, each self-antigen is expressed only in 1–3% of mTECs). How this mosaic pattern is generated at the single-cell level is currently not understood. Here, we show that subsets of human mTECs expressing a particular TRA coexpress distinct sets of genes. We identified three coexpression groups comprising overlapping and complementary gene sets, which preferentially mapped to certain chromosomes and intrachromosomal gene clusters. Coexpressed gene loci tended to colocalize to the same nuclear subdomain. The TRA subsets aligned along progressive differentiation stages within the mature mTEC subset and, in vitro, interconverted along this sequence. Our data suggest that single mTECs shift through distinct gene pools, thus scanning a sizeable fraction of the overall repertoire of promiscuously expressed self-antigens. These findings have implications for the temporal and spatial (re)presentation of self-antigens in the medulla in the context of tolerance induction.

Pinto, Sheena; Michel, Chloe; Schmidt-Glenewinkel, Hannah; Harder, Nathalie; Rohr, Karl; Wild, Stefan; Brors, Benedikt; Kyewski, Bruno

2013-01-01

358

Enhancing Students' Learning Process Through Self-Generated Tests  

NASA Astrophysics Data System (ADS)

The use of new technologies in higher education has surprisingly emphasized students' tendency to adopt a passive behavior in class. Participation and interaction of students are essential to improve academic results. This paper describes an educational experiment aimed at the promotion of students' autonomous learning by requiring them to generate test type questions related to the contents of the course. The main idea is to make the student feel part of the evaluation process by including students' questions in the evaluation exams. A set of applications running on our university online learning environment has been developed in order to provide both students and teachers with the necessary tools for a good interaction between them. Questions uploaded by students are visible to every enrolled student as well as to each involved teacher. In this way, we enhance critical analysis skills, by solving and finding possible mistakes in the questions sent by their fellows. The experiment was applied over 769 students from 12 different courses. Results show that the students who have actively participated in the experiment have obtained better academic performance.

Sanchez-Elez, Marcos; Pardines, Inmaculada; Garcia, Pablo; Miñana, Guadalupe; Roman, Sara; Sanchez, Margarita; Risco, Jose Luis

2013-03-01

359

Activists Ten Years Later: A Test of Generational Unit Continuity  

ERIC Educational Resources Information Center

This study focuses on the generational unit born out of the student protest movement and the long-range consequences of having been involved in a social movement. Three alternative sets of consequences were explored: maturation, dissillusionment, and generational conflict which creates a distinctive generational unit. The results strongly suggest…

Fendrich, James M.

1974-01-01

360

Different patterns of language activation in post-stroke aphasia are detected by overt and covert versions of the verb generation fMRI task  

PubMed Central

Summary Background Post-stroke language functions depend on the relative contributions of the dominant and non-dominant hemispheres. Thus, we aimed to identify the neural correlates of overt and covert verb generation in adult post-stroke aphasia. Material/Methods Sixteen aphasic LMCA stroke patients (SPs) and 32 healthy controls (HCs) underwent language testing followed by fMRI while performing an overt event-related verb generation task (ER-VGT) isolating activations related to noun-verb semantic processing or to articulation and auditory processing, and a covert block design verb generation task (BD-VGT). Results BD-VGT activation patterns were consistent with previous studies, while ER-VGT showed different patterns in SPs relative to HCs including less left-hemispheric involvement during semantic processing and predominantly right-sided activation related to articulation and auditory processing. ER-VGT intra-scanner performance was positively associated with activation during semantic associations in the left middle temporal gyrus for HCs (p=0.031) and left middle frontal gyrus for SPs (p=0.042). Increased activation in superior frontal/cingulate gyri was associated with better intra-scanner performance (p=0.020). Lesion size negatively impacted verbal fluency tested with Controlled Oral Word Association Test (p=0.0092) and the Semantic Fluency Test (p=0.033) and trended towards a negative association with verb generation performance on the event-related verb generation task (p=0.081). Conclusions Greater retention of pre-stroke language skills is associated with greater involvement of the left hemisphere with different cortical recruitment patterns observed in SPs versus HCs. Post-stroke verbal fluency may depend more upon the structural and functional integrity of the dominant left hemisphere language network rather than the shift to contralateral homologues.

Allendorfer, Jane B.; Kissela, Brett M.; Holland, Scott K.; Szaflarski, Jerzy P.

2012-01-01

361

A Tool for Automated Test Code Generation from High-Level Petri Nets  

Microsoft Academic Search

\\u000a Automated software testing has gained much attention because it is expected to improve testing productivity and reduce testing\\u000a cost. Automated generation and execution of tests, however, are still very limited. This paper presents a tool, ISTA (Integration\\u000a and System Test Automation), for automated test generation and execution by using high-level Petri nets as finite state test\\u000a models. ISTA has several

Dianxiang Xu

362

Field test of two high-pressure direct-contact downhole steam generators. Volume II. Oxygen/diesel system  

SciTech Connect

A field test of an oxygen/diesel fuel, direct contact steam generator has been completed. The field test, which was a part of Project DEEP STEAM and was sponsored by the US Department of Energy, involved the thermal stimulation of a well pattern in the Tar Zone of the Wilmington Oil Field. The activity was carried out in cooperation with the City of Long Beach and the Long Beach Oil Development Company. The steam generator was operated at ground level, with the steam and combustion products delivered to the reservoir through 2022 feet of calcium-silicate insulated tubing. The objectives of the test included demonstrations of safety, operational ease, reliability and lifetime; investigations of reservoir response, environmental impact, and economics; and comparison of those points with a second generator that used air rather than oxygen. The test was extensively instrumented to provide the required data. Excluding interruptions not attributable to the oxygen/diesel system, steam was injected 78% of the time. System lifetime was limited by the combustor, which required some parts replacement every 2 to 3 weeks. For the conditions of this particular test, the use of trucked-in LOX resulted in liess expense than did the production of the equivalent amount of high pressure air using on site compressors. No statistically significant production change in the eight-acre oxygen system well pattern occurred during the test, nor were any adverse effects on the reservoir character detected. Gas analyses during the field test showed very low levels of SOX (less than or equal to 1 ppM) in the generator gaseous effluent. The SOX and NOX data did not permit any conclusion to be drawn regarding reservoir scrubbing. Appreciable levels of CO (less than or equal to 5%) were measured at the generator, and in this case produced-gas analyses showed evidence of significant gas scrubbing. 64 figures, 10 tables.

Moreno, J.B.

1983-07-01

363

Nanophotonic reservoir computing with photonic crystal cavities to generate periodic patterns.  

PubMed

Reservoir computing (RC) is a technique in machine learning inspired by neural systems. RC has been used successfully to solve complex problems such as signal classification and signal generation. These systems are mainly implemented in software, and thereby they are limited in speed and power efficiency. Several optical and optoelectronic implementations have been demonstrated, in which the system has signals with an amplitude and phase. It is proven that these enrich the dynamics of the system, which is beneficial for the performance. In this paper, we introduce a novel optical architecture based on nanophotonic crystal cavities. This allows us to integrate many neurons on one chip, which, compared with other photonic solutions, closest resembles a classical neural network. Furthermore, the components are passive, which simplifies the design and reduces the power consumption. To assess the performance of this network, we train a photonic network to generate periodic patterns, using an alternative online learning rule called first-order reduced and corrected error. For this, we first train a classical hyperbolic tangent reservoir, but then we vary some of the properties to incorporate typical aspects of a photonics reservoir, such as the use of continuous-time versus discrete-time signals and the use of complex-valued versus real-valued signals. Then, the nanophotonic reservoir is simulated and we explore the role of relevant parameters such as the topology, the phases between the resonators, the number of nodes that are biased and the delay between the resonators. It is important that these parameters are chosen such that no strong self-oscillations occur. Finally, our results show that for a signal generation task a complex-valued, continuous-time nanophotonic reservoir outperforms a classical (i.e., discrete-time, real-valued) leaky hyperbolic tangent reservoir (normalized root-mean-square errors=0.030 versus NRMSE=0.127). PMID:24807033

Fiers, Martin Andre Agnes; Van Vaerenbergh, Thomas; Wyffels, Francis; Verstraeten, David; Schrauwen, Benjamin; Dambre, Joni; Bienstman, Peter

2014-02-01

364

Regional distribution of putative rhythm-generating and pattern-forming components of the mammalian locomotor CPG.  

PubMed

The ventromedial spinal cord of mammals contains a neural network known as the locomotor central pattern generator (CPG) which underlies the basic generation and coordination of muscle activity during walking. To understand how this neural network operates, it is necessary to identify, characterize, and map connectivity among its constituent cells. Recently, a series of studies have analyzed the activity pattern of interneurons that are rhythmically active during locomotion and suggested that they belong to one of two functional levels; one responsible for rhythm generation and the other for pattern formation. Here we use electrophysiological techniques to identify locomotor-related interneurons in the lumbar spinal cord of the neonatal mouse. By analyzing their activity during spontaneous deletions that occur during fictive locomotion we are able to distinguish between those likely to belong to the rhythm-generating and pattern-forming levels, and determine the regional distribution of each. Anatomical tracing techniques are also employed to investigate the morphological characteristics of cells belonging to each level. Results demonstrate that putative rhythm-generating cells are medially located and extend locally projecting axons, while those with activity consistent with pattern formation are located more laterally and send axonal projections to the lateral edge of the spinal cord, in the direction of the motoneuron pools. Results of this study provide insight into the detailed anatomical organization of the locomotor CPG. PMID:23933310

Griener, A; Dyck, J; Gosgnach, S

2013-10-10

365

Using GUI Run-Time State as Feedback to Generate Test Cases  

Microsoft Academic Search

This paper presents a new automated model-driven tech- nique to generate test cases by using feedback from the ex- ecution of a ìseed test suiteî on an application under test (AUT). The test cases in the seed suite are designed to be generated automatically and executed very quickly. During their execution, feedback obtained from the AUT's run-time state is used

Xun Yuan; Atif M. Memon

2007-01-01

366

Auto-generation and redundancy reduction of test cases for reactive systems  

Microsoft Academic Search

Testing is the fundamental technique to assess the correctness of software systems, but it is cost-labored to generate test cases. One solution to change the situation is to automatize some parts of the testing process, especially the generation of test cases using formal theory and technology. The research work in the direction shows the good perspective. This paper targets on

Donghuo Chen; Xuandong Li; Shizhong Zhao

2010-01-01

367

Voltage endurance test facility for electric generator stator coils  

Microsoft Academic Search

The development of new coil designs with the use of updated materials and\\/or processes requires voltage endurance testing as one of the tests to verify the new coil design. From established voltage endurance curves, a new insulation system can be evaluated against accepted coil designs. An expanded voltage endurance test lab has been developed which has the capabilities for testing

F. T. Emery; R. F. Weddleton

1993-01-01

368

Ocular Ferning Test – Effect of Temperature and Humidity on Tear Ferning Patterns  

Microsoft Academic Search

Background: The ocular ferning test is used as a diagnostic aid to evaluate patients with dry-eye disease. The ferning phenomenon is a dendritic growth form of dried tear fluid. The influence of temperature and relative humidity (rH) on the morphology of tear ferning patterns was investigated. Methods: Two microliters of tear fluid of 5 volunteers with normal tear function were

Jutta Horwath; Karl Ettinger; Maria Bachernegg; Elizabeth Bodner; Otto Schmut

2001-01-01

369

Automatic Path-Oriented Test Data Generation Using a Multi-population Genetic Algorithm  

Microsoft Academic Search

Automatic path-oriented test data generation is an undecidable problem and genetic algorithm (GA) has been used to test data generation since 1992. In favor of MATLAB, a multi-population genetic algorithm (MPGA) was implemented, which selects individuals for free migration based on their fitness values. Applying MPGA to generating path-oriented test data generation is a new and meaningful attempt. After depicting

Yong Chen; Yong Zhong

2008-01-01

370

GENETIC ACTIVITY PROFILES AND PATTERN RECOGNITION IN TEST BATTERY SELECTION (JOURNAL VERSION)  

EPA Science Inventory

Computer-generated genetic activity profiles and pairwise matching procedures may aid in the selection of the most appropriate short-term bioassays to be used in test batteries for the evaluation of the genotoxicity of a given chemical or group of chemicals. Selection of test bat...

371

Empirical evaluation of optimization algorithms when used in goal-oriented automated test data generation techniques  

Microsoft Academic Search

Software testing is an essential process in software development. Software testing is very costly, often consuming half the\\u000a financial resources assigned to a project. The most laborious part of software testing is the generation of test-data. Currently,\\u000a this process is principally a manual process. Hence, the automation of test-data generation can significantly cut the total\\u000a cost of software testing and

Man Xiao; Mohamed El-attar; Marek Reformat; James Miller

2007-01-01

372

SfW method: Delay test generation for simple chain wrapper architecture  

Microsoft Academic Search

The aim of the presented work is to improve the quality of testing of SoC digital cores surrounded with test wrappers. The paper presents a new effective delay fault test generation method for the transition faults based on the skewed-load test. The generated delay fault test can be applied to a SoC core through a test wrapper architecture with only

M. Bala?z

2010-01-01

373

Experiment Data Report for Semiscale MOD-1 Test S-28-6 (Steam Generator Tube Rupture Test).  

National Technical Information Service (NTIS)

Recorded test data are presented for Test S-28-6 of the Semiscale Mod-1 steam generator tube rupture test series. These tests are among several Semiscale Mod-1 experiments conducted to investigate the thermal and hydraulic phenomena accompanying a hypothe...

M. L. Patton K. E. Sackett C. E. Coppin

1977-01-01

374

Experiments and viscoelastic analysis of peel test with patterned strips for applications to transfer printing  

NASA Astrophysics Data System (ADS)

Transfer printing is an exceptionally sophisticated approach to assembly and micro-/nanofabrication that relies on a soft, elastomeric 'stamp' to transfer solid, micro-/nanoscale materials or device components from one substrate to another, in a large-scale, parallel fashion. The most critical control parameter in transfer printing is the strength of adhesion between the stamp and materials/devices. Conventional peel tests provide effective and robust means for determining the interfacial adhesion strength, or equivalently the energy release rate, and its dependence on peel speed. The results presented here provide analytic solutions for tests of this type, performed using viscoelastic strips with and without patterns of relief on their surfaces, and validated by systematic experiments. For a flat strip, a simple method enables determination of the energy release rate as a function of the peel speed. Patterned strips can be designed to achieve desired interfacial properties, with either stronger or weaker adhesion than that for a flat strip. The pattern spacing influences the energy release rate, to give values that initially decrease to levels smaller than those for a corresponding flat strip, as the pattern spacing increases. Once the spacing reaches a critical value, the relief self-collapses onto the substrate, thereby significantly increasing the contact area and the strength of adhesion. Analytic solutions capture not only these behaviors, as confirmed by experiment, but also extend to strips with nearly any pattern geometry of cylindrical pillars.

Chen, Hang; Feng, Xue; Huang, Yin; Huang, Yonggang; Rogers, John A.

2013-08-01

375

Experimental Study on GA-Based Path-Oriented Test Data Generation Using Branch Distance Function  

Microsoft Academic Search

Automatic path-oriented test data generation is not only a key problem but a hot issue in the research area of software testing today. Genetic algorithm (GA) has been used to path-oriented test data generation since 1992 and outperforms other approaches. A fitness function based on branch distance (BDBFF) has been applied in GA-based path-oriented test data generation. To investigate performance

Yong Chen; Yong Zhong

2009-01-01

376

Auto-generating Test Sequences Using Model Checkers: A Case Study  

Microsoft Academic Search

Use of model-checking approaches for test generation from requirement models have been proposed by several researchers. These approaches leverage the witness (or counter-example) generation capability of model-checkers for constructing test cases. Test criteria are expressed as temporal properties. Witness traces generated for these properties are instantiated to create complete test se- quences, satisfying the criteria. State-space explosion can, however, adversely

Mats Per Erik Heimdahl; Sanjai Rayadurgam; Willem Visser; George Devaraj; Jimin Gao

2003-01-01

377

PWR steam generator chemical cleaning process testing in model steam generators  

Microsoft Academic Search

Corrosion related problems in PWR power plant steam generators have caused high maintenance costs, increased radiation exposure to plant personnel, and reduced unit availability. Two cleaning methods were investigated for their ability to clean deposits from steam generators thereby increasing the integrity of the steam generators and reducing personnel radiation exposure, due to reduced maintenance. First, an on-line chemical cleaning

F. E. Jr. Swan; A. A. Katterhenry; S. Mostovoy; P. Latash; G. S. Gerzen

1984-01-01

378

A study in coverage-driven test generation  

Microsoft Academic Search

1. ABSTRACT One possible solution to the verification crisis is to bridge the gap between formal verification and simulation by using hybrid techniques. This paper presents a study of such a functional verification methodology that uses coverage of formal models to specify tests. This was applied to a modern superscalar microprocessor and the resulting tests were compared to tests gen-

Mike Benjamin; Daniel Geist; Alan Hartman; Gerard Mas; Ralph Smeets; Yaron Wolfsthal

1999-01-01

379

Demonstration of full-field patterning of 32 nm test chips using EUVL  

NASA Astrophysics Data System (ADS)

EUV lithography is considered one of the options for high volume manufacturing (HVM) of 16 nm MPU node devices [1]. The benefits of high k1(~0.5) imaging enable EUVL to simplify the patterning process and ease design rule restrictions. However, EUVL with its unique imaging process - reflective optics and masks, vacuum operation, and lack of pellicle, has several challenges to overcome before being qualified for production. Thus, it is important to demonstrate the capability to integrate EUVL into existing process flows and characterize issues which could hamper yield. A patterning demonstration of Intel's 32 nm test chips using the ADT at IMEC [7] is presented, This test chip was manufactured using processes initially developed with the Intel MET [2-4] as well as masks made by Intel's mask shop [5,6]. The 32 nm node test chips which had a pitch of 112.5 nm at the trench layer, were patterned on the ADT which resulted in a large k1 factor of 1 and consequently, the trench process window was iso-focal with MEEF = 1. It was found that all mask defects detected by a mask pattern inspection tool printed on the wafer and that 90% of these originated from the substrate. We concluded that improvements are needed in mask defects, photospeed of the resist, overlay, and tool throughput of the tool to get better results to enable us to ultimately examine yield.

Vandentop, Gilroy; Chandhok, Manish; Putna, Ernisse S.; Younkin, Todd R.; Clarke, James S.; Carson, Steven; Myers, Alan; Leeson, Michael; Zhang, Guojing; Liang, Ted; Murachi, Tetsunori

2009-03-01

380

Generation of design verification tests from behavioral VHDL programs using path enumeration and constraint programming  

Microsoft Academic Search

A method for generation of design verification tests from behavior-level VHDL programs is presented. The method generates stimuli to execute desired control-flow paths in the given VHDL program. This method is based on path enumeration, constraint generation and constraint solving techniques that have been traditionally used for software testing. Behavioral VHDL programs contain multiple communicating processes, signal assignment statements, and

Ranga Vemuri; R. Kalyanaraman

1995-01-01

381

Computerized In Vitro Test for Chemical Toxicity Based on Tetrahymena Swimming Patterns  

NASA Technical Reports Server (NTRS)

An apparatus and a method for rapidly determining chemical toxicity have been evaluated as an alternative to the rabbit eye initancy test (Draize). The toxicity monitor includes an automated scoring of how motile biological cells (Tetrahymena pyriformis) slow down or otherwise change their swimming patterns in a hostile chemical environment. The method, called the motility assay (MA), is tested for 30 s to determine the chemical toxicity in 20 aqueous samples containing trace organics and salts. With equal or better detection limits, results compare favorably to in vivo animal tests of eye irritancy.

Noever, David A.; Matsos, Helen C.; Cronise, Raymond J.; Looger, Loren L.; Relwani, Rachna A.; Johnson, Jacqueline U.

1994-01-01

382

Digital generator for adjustment and testing of electrical prospecting equipment  

Microsoft Academic Search

The block diagram is described of a circuit that generates a digital signal representing a sum of exponents with initial values and attenuation constants against the background of sinusoidal noise of a given frequency and amplitude.

P. P. Dravich

1993-01-01

383

Digital generator for adjustment and testing of electrical prospecting equipment  

Microsoft Academic Search

The block diagram is described of a circuit that generates a digital signal representing a sum of exponents with initial values and attenuation constants against the background of sinusoidal noise of a given frequency and amplitude.

Dravich

1994-01-01

384

Testing of the Mark 101 magnetic flux compression generator  

Microsoft Academic Search

The Mark 101 explosive flux compression generator is a line-initiated, vacuum\\/magnetically insulated, helical generator. This device offered some unique challenges in transforming the theoretical design into a testable experiment. The two main reasons for this are that in theory an eight-turn, four-wire Mark 101 possesses a terminal dL\\/dt of approx.0.5 ..cap omega.. and operates with electric fields which are greater

B. L. Freeman; C. M. Fowler; J. C. King; A. R. Martinez

1986-01-01

385

Initial benchmarking of a new electron-beam raster pattern generator for 130-100 nm maskmaking  

NASA Astrophysics Data System (ADS)

The decision by the Semiconductor Industry Association (SIA) to accelerate the continuing evolution to smaller linewidths is consistent with the commitment by Etec Systems, Inc. to rapidly develop new technologies for pattern generation systems with improved resolution, critical dimension (CD) uniformity, positional accuracy, and throughput. Current pattern generation designs are inadequate to meet the more advanced requirements for masks, particularly at or below the 100 nm node. Major changes to all pattern generation tools will be essential to meet future market requirements. An electron-beam (e-beam) system that is designed to meet the challenges for 130 - 100 nm device generation with extendibility to the 70-nm range will be discussed. This system has an architecture that includes a graybeam writing strategy, a new state system, and improved thermal management. Detailed changes include a pulse width modulated blanking system, per-pixel deflection, retrograde scanning multipass writing, and a column with a 50 kV accelerating voltage that supports a dose of up to 45 (mu) C/cm2 with minimal amounts of resist heating. This paper examines current issues, our approach to meeting International Technology Roadmap for Semiconductors (ITRS) requirements, and some preliminary results from a new pattern generator.

Sauer, Charles A.; Abboud, Frank E.; Babin, Sergey V.; Chakarian, Varoujan; Ghanbari, Abe; Innes, Robert; Trost, David; Raymond, Frederick, III

2000-07-01

386

The contribution of a central pattern generator in a reflex-based neuromuscular model  

PubMed Central

Although the concept of central pattern generators (CPGs) controlling locomotion in vertebrates is widely accepted, the presence of specialized CPGs in human locomotion is still a matter of debate. An interesting numerical model developed in the 90s’ demonstrated the important role CPGs could play in human locomotion, both in terms of stability against perturbations, and in terms of speed control. Recently, a reflex-based neuro-musculo-skeletal model has been proposed, showing a level of stability to perturbations similar to the previous model, without any CPG components. Although exhibiting striking similarities with human gaits, the lack of CPG makes the control of speed/step length in the model difficult. In this paper, we hypothesize that a CPG component will offer a meaningful way of controlling the locomotion speed. After introducing the CPG component in the reflex model, and taking advantage of the resulting properties, a simple model for gait modulation is presented. The results highlight the advantages of a CPG as feedforward component in terms of gait modulation.

Dzeladini, Florin; van den Kieboom, Jesse; Ijspeert, Auke

2014-01-01

387

Multislit interference patterns in high-order harmonic generation in C{sub 60}  

SciTech Connect

We study high-order harmonic generation in C{sub 60} molecules interacting with a linearly polarized intense short laser pulse at near- and mid-infrared wavelengths, using an extension of the so-called three-step or Lewenstein model to the molecular case. The results exhibit modulations in the plateaus of the spectra at the longer wavelengths, which are present for ensembles of aligned as well as randomly oriented fullerenes. The analysis of the results show that the minima can be explained by a multislit interference effect arising from the contributions of the 60 atomic centers to the dipole moment. Good agreement between the positions of the minima in the spectra obtained in the length gauge are found with those of the recombination matrix element, but not for those in the velocity gauge calculations. We further use a simple spherical model to analyze how geometrical information, such as the radius of the fullerene cage, can be obtained from the interference pattern in the harmonic spectra.

Ciappina, M. F.; Becker, A.; Jaron-Becker, A. [Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden (Germany); Institut fuer Physikalische Chemie und Elektrochemie, Technische Universitaet Dresden, D-01062 Dresden (Germany)

2007-12-15

388

Computerized reminders for five preventive screening tests: generation of patient-specific letters incorporating physician preferences.  

PubMed Central

Compliance with preventive screening tests is inadequate in the United States. We describe a computer based system for generating reminder letters to patients who may have missed their indicated screening tests because they do not visit a provider regularly or missed their tests despite the fact that they do visit a provider. We started with national recommendations and generated a local consensus for test indications. We then used this set of indications and our electronic record to determine test deficiencies in our pilot pool of 3073 patients. The computer generated customized reminder letters targeting several tests. Physicians chose any patients who should not receive letters. The response rate for fecal occult blood (FOB) testing was 33% compared with an 18% historical compliance rate within the same community. FOB reminders generated improved test compliance. Test execution must be considered when commencing a program of screening test reminders.

Murphy, D. J.; Gross, R.; Buchanan, J.

2000-01-01

389

DESIGN, FABRICATION, AND TESTING OF AN ADVANCED, NON-POLLUTING TURBINE DRIVE GAS GENERATOR  

SciTech Connect

The objectives of this report period were to complete the development of the Gas Generator design, which was done; fabricate and test of the non-polluting unique power turbine drive gas Gas Generator, which has been postponed. Focus during this report period has been to complete the brazing and bonding necessary to fabricate the Gas Generator hardware, continue making preparations for fabricating and testing the Gas Generator, and continuing the fabrication of the Gas Generator hardware and ancillary hardware in preparation for the test program. Fabrication is more than 95% complete and is expected to conclude in early May 2002. the test schedule was affected by relocation of the testing to another test supplier. The target test date for hot fire testing is now not earlier than June 15, 2002.

Unknown

2002-03-31

390

Research on Intelligent Auto-Generating Test Paper Based on Improved Genetic Algorithms  

Microsoft Academic Search

The constraint conditions of the auto-generating test paper are analyzed. The mathematical model of intelligence test paper generation system is set up and a new method of composing test paper based on the improved genetic algorithm is given. The result of the experiments shows that the new method is more efficient and easier to deal with the problem of autogenerating

Wu Xiaoqin; Song Yin

2009-01-01

391

Generation of concentration gradient from a wave-like pattern by high frequency vibration of liquid–liquid interface  

Microsoft Academic Search

The fast and effective generation of a concentration gradient by mixing in the microchannel is important for many microfluidic\\u000a applications. The active control of gradient is useful for applying the measurement of cell responses by dynamic change of\\u000a environment. The main purpose of this paper is the generation of temporally stable concentration gradient actively. For this\\u000a purpose, the wave-like pattern

Kohei Motoo; Naoya Toda; Fumihito Arai; Toshio Fukuda; Kosuke Sekiyama; Masahiro Nakajima

2008-01-01

392

Stationary gas turbine-generator set acceptance testing procedures, methods, and instructions. Special report  

Microsoft Academic Search

Procedures for acceptance testing gas turbine-generator sets intended for installation in fixed military facilities are described. The new test procedures, numbered CE-TP-2001 through 2003, are designed for use by Corps of Engineers Division and District personnel. Also included are lists of MIL-STD-705B test methods and Corps of Engineers diesel engine generator set test procedures that apply directly to acceptance testing

E. M. Takemori; S. W. Lee

1977-01-01

393

Model Composition and Generating Tests for Web Applications  

Microsoft Academic Search

Nowadays, with the prevalence of Web applications, more and more services and information are available over the Internet while their correctness, security and reliability are often crucial to the success of business and organizations. Web testing is one of the methods to ensure the Web security. However, due to the special characters of Web applications, traditional testing methods are not

Bo Song; Shengwen Gong; Shengbo Chen

2011-01-01

394

Electronic speckle pattern shearing interferometry for nondestructive testing of thermal sprayed alloy coatings  

NASA Astrophysics Data System (ADS)

Thermal sprayed coatings have wide engineering applications. There now exists a wide range of destructive and nondestructive testing (NDT) methods for surface coating inspections. This paper describes an application of Electronic Speckle Pattern Shearing Interferometry (ESPSI) for NDT of thermal sprayed surface coatings. In contrast to other conventional methods such as eddy current, ultrasonic or X-ray, ESPSI allows fast and large survey area inspection. Experimental results of shearographic measurements are presented. Thermal sprayed coatings were tested using ESPSI. Delaminations of the coatings were detected and the fringe patterns were captured using this method. It is shown that the shearography technique can be applied successfully to surface coating quality inspection and it is very effective for delamination detection.

Xue, Yueqiang; Kennedy, David; Mihaylova, Emilia

2005-06-01

395

Characterization of photochromic computer-generated holograms for optical testing  

NASA Astrophysics Data System (ADS)

We investigate the possibility to produce photochromic CGHs with maskless lithography methods. For this purpose, optical properties and requirements of photochromic materials will be shown. A diarylethene-based polyurethane is developed and characterized. The resolution limit and the in uence of the writing parameters on the produced patterns, namely speed rate and light power, have been determined. After the optimization of the writing process, gratings and Fresnel Zone Plates are produced on the photochromic layer and diraction eciencies are measured. Improvements and perspectives will be discussed.

Pariani, Giorgio; Bertarelli, Chiara; Bianco, Andrea; Schaal, Frederik; Pruss, Christof

2012-09-01

396

A Drive Unit for the Testing of Tachometer-Generators.  

National Technical Information Service (NTIS)

A tachometer-generator drive unit is described which is capable of providing a range of discrete speeds from 500 rev/min to 6000 rev/min. Use is made of an existing Velodyne and its associated control circuit to which an additional phase sensitive error s...

P. A. Stickels

1967-01-01

397

Modeling monkeys: A comparison of computer-generated and naturally occurring foraging patterns in two species of neotropical primates  

Microsoft Academic Search

We present a series of computer-generated foraging models (random movement, olfactory navigation, and spatial memory) designed to examine the manner in which sensory cues and cognitive skills might be used by rainforest monkeys to locate patchily distributed feeding sites. These simulations are compared with data collected in the Amazon Basin of northeastern Peru on the foraging patterns of two species

P. A. Garber; B. Hannon

1993-01-01

398

Second-harmonic generation of a tunable continuous-wave CO2 laser in orientation-patterned GaAs.  

PubMed

Tunable, mid-infrared radiation was obtained by frequency doubling of a continuous-wave CO(2) laser in orientation-patterned GaAs crystal. Active cooling of the crystal minimized pump-induced thermal effects, allowing generation of output powers exceeding 300 mW across the wavelength range of 4.63-4.78 ?m. PMID:23381424

Gonzalez, Leonel P; Upchurch, Derek C; Schunemann, Peter G; Mohnkern, Lee; Guha, Shekhar

2013-02-01

399

Multiple hypotheses testing of fish incidence patterns in an urbanized ecosystem  

Microsoft Academic Search

Ecological and evolutionary theories have focused traditionally on natural processes with little attempt to incorporate anthropogenic\\u000a influences despite the fact that humans are such an integral part of virtually all ecosystems. A series of alternate models\\u000a that incorporated anthropogenic factors and traditional ecological mechanisms of invasion to account for fish incidence patterns\\u000a in urban lakes was tested. The models were

C. J. Chizinski; C. L. Higgins; C. E. Shavlik; K. L. Pope

2006-01-01

400

Stereotypic Laryngeal and Respiratory Motor Patterns Generate Different Call Types in Rat Ultrasound Vocalization  

PubMed Central

Rodents produce highly variable ultrasound whistles as communication signals unlike many other mammals, who employ flow-induced vocal fold oscillations to produce sound. The role of larynx muscles in controlling sound features across different call types in ultrasound vocalization (USV) was investigated using laryngeal muscle electromyographic (EMG) activity, subglottal pressure measurements and vocal sound output in awake and spontaneously behaving Sprague–Dawley rats. Results support the hypothesis that glottal shape determines fundamental frequency. EMG activities of thyroarytenoid and cricothyroid muscles were aligned with call duration. EMG intensity increased with fundamental frequency. Phasic activities of both muscles were aligned with fast changing fundamental frequency contours, for example in trills. Activities of the sternothyroid and sternohyoid muscles, two muscles involved in vocal production in other mammals, are not critical for the production of rat USV. To test how stereotypic laryngeal and respiratory activity are across call types and individuals, sets of ten EMG and subglottal pressure parameters were measured in six different call types from six rats. Using discriminant function analysis, on average 80% of parameter sets were correctly assigned to their respective call type. This was significantly higher than the chance level. Since fundamental frequency features of USV are tightly associated with stereotypic activity of intrinsic laryngeal muscles and muscles contributing to build-up of subglottal pressure, USV provide insight into the neurophysiological control of peripheral vocal motor patterns.

RIEDE, TOBIAS

2014-01-01

401

Control Theoretic Modeling and Generated Flow Patterns of a Fish-Tail Robot  

NASA Astrophysics Data System (ADS)

Many real-world engineering problems involve understanding and manipulating fluid flows. One of the challenges to further progress in the area of active flow control is the lack of appropriate models that are amenable to control-theoretic studies and algorithm design and also incorporate reasonably realistic fluid dynamic effects. We focus here on modeling and model-verification of bio-inspired actuators (fish-fin type structures) used to control fluid dynamic artifacts that will affect speed, agility, and stealth of Underwater Autonomous Vehicles (UAVs). Vehicles using fish-tail type systems are more maneuverable, can turn in much shorter and more constrained spaces, have lower drag, are quieter and potentially more efficient than those using propellers. We will present control-theoretic models for a simple prototype coupled fluid and mechanical actuator where fluid effects are crudely modeled by assuming only lift, drag, and added mass, while neglecting boundary effects. These models will be tested with different control input parameters on an experimental fish-tail robot with the resulting flow captured with DPIV. Relations between the model, the control function choices, the obtained thrust and drag, and the corresponding flow patterns will be presented and discussed.

Massey, Brian; Morgansen, Kristi; Dabiri, Dana

2003-11-01

402

Adenosine A1 receptors modulate high voltage-activated Ca2+ currents and motor pattern generation in the Xenopus embryo  

PubMed Central

Adenosine causes voltage- and non-voltage-dependent inhibition of high voltage-activated (HVA) Ca2+ currents in Xenopus laevis embryo spinal neurons. As this inhibition can be blocked by 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) and mimicked by N6-cyclopentyladenosine (CPA) it appears to be mediated by A1 receptors. Agents active at A2 receptors either were without effect or could be blocked by DPCPX. AMP had no agonist action on these receptors. By using ?-conotoxin GVIA we found that adenosine inhibited an N-type Ca2+ current as well as a further unidentified HVA current that was insensitive to dihydropyridines, ?-agatoxin TK and ?-conotoxin MVIIC. Both types of current were subject to voltage- and non-voltage-dependent inhibition. We used CPA and DPCPX to test whether A1 receptors regulated spinal motor pattern generation in spinalized Xenopus embryos. DPCPX caused a near doubling of, while CPA greatly shortened, the length of swimming episodes. In addition, DPCPX slowed, while CPA greatly speeded up, the rate of run-down of motor activity. Our results demonstrate a novel action of A1 receptors in modulating spinal motor activity. Furthermore they confirm that adenosine is produced continually throughout swimming episodes and acts to cause the eventual termination of activity.

Brown, Paul; Dale, Nicholas

2000-01-01

403

Artificial combination of two cis-regulatory elements generates a unique pattern of expression in transgenic plants.  

PubMed

We show that a 36-base-pair-long upstream fragment from the soybean hsp17.3-B gene comprising two partly overlapping heat-shock element (HSE)-like sequences can confer heat inducibility to a reporter gene in transgenic tobacco. The heat-shock response does not display organ specificity and is not affected by light. Insertion of these HSE-like elements into the pea rbcS-3A 5' flanking fragment (position -410 to +15) either at position -410 (5' to the enhancer) or at position -49 (between the enhancer and the "TATA" box) renders the transcript level of the reporter gene light-inducible and organ-specific under heat-shock conditions. These results demonstrate the possibility of generating a unique pattern of expression (e.g., light-dependent and organ-specific heat-shock response) by artificial combination of appropriate cis-acting regulatory elements. Moreover, by using the HSE-like sequences as a weak heat-inducible enhancer in the chimeric regulatory regions we uncover the function of negative elements within the pea rbcS-3A upstream region. These negative elements are responsible for a repressed transcript level in roots as well as in dark-adapted leaves. Therefore, the upstream fragment containing two HSE-like elements can be considered a useful tool to test the function of other cis-acting elements. PMID:3480523

Strittmatter, G; Chua, N H

1987-12-01

404

NEXT GENERATION SEDIMENT TOXICITY TESTING VIA DNA MICROARRAYS - PHASE I  

EPA Science Inventory

The current SBIR solicitation states that the EPA is seeking ?better sampling, analysis, and monitoring technologies? to improve hazardous waste management.  Development of new methods for testing contaminated sediments is an area of particular concern because many industri...

405

40 CFR 86.1333-90 - Transient test cycle generation.  

Code of Federal Regulations, 2013 CFR

...test. The torque and rpm feedback signals may be filtered. (d) Idle Speed Enhancement Devices (e.g. cold idle, alternator idle, etc.). For an engine equipped with an idle speed enhancement device, the zero percent speed specified in...

2013-07-01

406

Generating Test Case from Functional Requirement of Web Applications  

Microsoft Academic Search

E-commerce has been developing rapidly around the world. We run Web application to support e-commerce. Quality of Web applications influences the functionalities and security of e-commerce. Modeling and testing are important to quality of web applications. Many researchers are still to find effective ways to model and test Web applications. Formal methods can improve the quality of Web applications. This

Bin Zhu; Huaikou Miao; Hongwei Zeng; Shengbo Chen

2009-01-01

407

Replication and Extension of Measurement Models for the Manikin Test, Sternberg Memory Test, and Pattern Recognition Test.  

National Technical Information Service (NTIS)

Computerized cognitive assessment batteries provide potentially valuable methods of assessing cognitive performance in field settings, but it often is difficult to follow recommendations for extensive baseline testing in these settings. The performance of...

R. R. Vickers R. Hilbert J. A. Hodgdon R. L. Hessink A. C. Hackney

1991-01-01

408

Microcontact printing of axon guidance molecules for generation of graded patterns.  

PubMed

Microcontact printing (microCP) of proteins has been successfully used for patterning surfaces in various contexts. Here we describe a simple 'lift-off' method to print precise patterns of axon guidance molecules, which are used as substrate for growing chick retinal ganglion cell (RGC) axons. Briefly, the etched pattern of a silicon master is transferred to a protein-coated silicone cuboid (made from polydimethylsiloxane, PDMS), which is then used as a stamp on a glass coverslip. RGC explants are placed adjacent to the pattern and cultured overnight. Fluorescent labeling of the printed proteins allows the quantitative analysis of the interaction of axons and growth cones with single protein dots and of the overall outgrowth and guidance rate in variously designed patterns. Patterned substrates can be produced in 3-4 h and are stable for up to one week at 4 degrees C; the entire protocol can be completed in 3 d. PMID:17406418

von Philipsborn, Anne C; Lang, Susanne; Bernard, André; Loeschinger, Jürgen; David, Christian; Lehnert, Dirk; Bastmeyer, Martin; Bonhoeffer, Friedrich

2006-01-01

409

Real-time biomimetic Central Pattern Generators in an FPGA for hybrid experiments  

PubMed Central

This investigation of the leech heartbeat neural network system led to the development of a low resources, real-time, biomimetic digital hardware for use in hybrid experiments. The leech heartbeat neural network is one of the simplest central pattern generators (CPG). In biology, CPG provide the rhythmic bursts of spikes that form the basis for all muscle contraction orders (heartbeat) and locomotion (walking, running, etc.). The leech neural network system was previously investigated and this CPG formalized in the Hodgkin–Huxley neural model (HH), the most complex devised to date. However, the resources required for a neural model are proportional to its complexity. In response to this issue, this article describes a biomimetic implementation of a network of 240 CPGs in an FPGA (Field Programmable Gate Array), using a simple model (Izhikevich) and proposes a new synapse model: activity-dependent depression synapse. The network implementation architecture operates on a single computation core. This digital system works in real-time, requires few resources, and has the same bursting activity behavior as the complex model. The implementation of this CPG was initially validated by comparing it with a simulation of the complex model. Its activity was then matched with pharmacological data from the rat spinal cord activity. This digital system opens the way for future hybrid experiments and represents an important step toward hybridization of biological tissue and artificial neural networks. This CPG network is also likely to be useful for mimicking the locomotion activity of various animals and developing hybrid experiments for neuroprosthesis development.

Ambroise, Matthieu; Levi, Timothee; Joucla, Sebastien; Yvert, Blaise; Saighi, Sylvain

2013-01-01

410

Bidirectional plasticity of pontine pneumotaxic postinspiratory drive: implication for a pontomedullary respiratory central pattern generator.  

PubMed

The "pneumotaxic center" in the rostral dorsolateral pons as delineated by Lumsden nine decades ago is known to play an important role in promoting the inspiratory off-switch (IOS) for inspiratory-expiratory phase transition as a fail-safe mechanism for preventing apneusis in the absence of vagal input. Traditionally, the pontine pneumotaxic mechanism has been thought to contribute a tonic descending input that lowers the IOS threshold in medullary respiratory central pattern generator (rCPG) circuits, but otherwise does not constitute part of the rCPG. Recent evidence indicates that descending input from the Kölliker-Fuse nucleus (KFN) within the pneumotaxic center is essential for gating the postinspiratory phase of the three-phase respiratory rhythm to control the IOS in vagotomized animals. A critical question arising is whether such a descending pneumotaxic input from KFN that drives postinspiratory activity is tonic (null hypothesis) or rhythmic with postinspiratory phase modulation (alternative hypothesis). Here, we show that multifarious evidence reported in the literature collectively indicates that the descending pneumotaxic input may exhibit NMDA receptor-dependent short-term plasticity in the form of a biphasic neural differentiator that bidirectionally and phase-selectively modulates postinspiratory phase duration in response to vagal and peripheral chemoreceptor inputs independent of the responses in inspiratory and late-expiratory activities. The phase-selectivity property of the descending pneumotaxic input implicates a population of pontine early-expiratory (postinspiratory/expiratory-decrementing) neurons as the most likely neural correlate of the pneumotaxic mechanism that drives post-I activity, suggesting that the pontine pneumotaxic mechanism may be an integral part of a pontomedullary rCPG that underlies the three-phase respiratory rhythm. PMID:24746051

Poon, Chi-Sang; Song, Gang

2014-01-01

411

Computerized in vitro test for chemical toxicity based on tetrahymena swimming patterns  

NASA Technical Reports Server (NTRS)

An apparatus and method for rapidly determining chemical toxicity was evaluated. The toxicity monitor includes an automated scoring of how motile biological cells (Tetrahymena pyriformis) slow down or otherwise change their swimming patterns in a hostile chemical environment. The device, called the Motility Assay Apparatus (MAA) is tested for 30 second determination of chemical toxicity in 20 aqueous samples containing trace organics and salts. With equal or better detection limits, results compare favorably to in vivo animal tests of eye irritancy, in addition to agreeing for all chemicals with previous manual evaluations of single cell motility.

Noever, David A.; Matsos, Helen C.; Cronise, Raymond J.; Looger, Loren L.; Relwani, Rachna A.; Johnson, Jacqueline U.

1994-01-01

412

Pattern recognition techniques for failure trend detection in SSME ground tests  

NASA Technical Reports Server (NTRS)

The Space Shuttle Main Engine (SSME) is a complex power plant. To evaluate its performance 1200 hot-wire ground tests have been conducted, varying in duration from 0 to 500 secs. During the test some 500 sensors are sampled every 20 ms. The sensors are generally bounded by red lines so that an excursion beyond could lead to premature shutdown. In 27 tests it was not possible to effect an orderly premature shutdown, resulting in major incidents with serious damage to the SSME and test stand. The application of pattern recognition are investigated to detect SSME performance trends that may lead to major incidents. Based on the sensor data a set of (n) features is defined. At any time during the test, the state of the SSME is given by a point in the n-dimensional feature space. The history of a test can now be represented as a trajectory in the n-dimensional feature space. Portions of the normal trajectories and failed test trajectories would lie in different regions of the n-dimensional feature space. The latter can now be partitioned into regions of normal and failed tests. Thus, it is possible to examine the trajectory of a test in progress and predict if it is going into the normal or failure region.

Choudry, A.

1987-01-01

413

Multistage Helical Flux Compression Generator Non-Explosive Test Bed  

Microsoft Academic Search

Helical flux compression generators of small dimensions have been shown to produce energy output around 3 kJ into an inductive load. Adding a fuse opening switch has allowed us to produce 300 kV into a 15 Ohm load. We are investigating inductive energy storage with emphasis on an electro-explosive fuse opening switch in order to improve upon previous results. We

D. Belt; J. Dickens; J. Mankowski; A. Neuber

2005-01-01

414

Generation of concentration gradient from a wave-like pattern by high frequency vibration of liquid-liquid interface.  

PubMed

The fast and effective generation of a concentration gradient by mixing in the microchannel is important for many microfluidic applications. The active control of gradient is useful for applying the measurement of cell responses by dynamic change of environment. The main purpose of this paper is the generation of temporally stable concentration gradient actively. For this purpose, the wave-like pattern of the liquid-liquid interface is produced in the microchannel. In this technique, the high frequency of the wave-like pattern is necessary for reducing the length of the mixing path. High frequency of the wave-like pattern is achieved by employing the newly developed microvalve using tailor-made multilayer piezoelectric actuators (TAMPA) that is compact yet produces large displacements and forces. This paper first details the concept for the concentration gradient generation method. Next, a microvalve (20 x 15 x 15 mm) was designed and produced using TAMPA (8.5 x 10 x 10 mm). Finally, a concentration gradient in two-layered flow was generated with the microvalve. As a result, the generation of a concentration gradient in two-layered flow with active mixing was achieved. Furthermore, it is shown that the concentration gradient can be controlled actively by adjusting the input voltage to TAMPA. PMID:18071908

Motoo, Kohei; Toda, Naoya; Arai, Fumihito; Fukuda, Toshio; Sekiyama, Kosuke; Nakajima, Masahiro

2008-06-01

415

Tests of Isothermal Soaking Procedures for Limiting Tube Denting in Nuclear Steam Generators.  

National Technical Information Service (NTIS)

Capsule and pot boiler tests were conducted to develop and to evaluate shutdown soak solutions and procedures for limiting dent growth in nuclear steam generators. Testing was limited to isothermal soaking in the absence of boiling heat transfer. The effe...

T. A. Beineke

1981-01-01

416

Demonstration Tests on PWR Steam Generator Tube-Tubesheet Crevice Flushing Procedures.  

National Technical Information Service (NTIS)

A series of autoclave tests was completed to evaluate the effectiveness of a flushing technique for removal of contaminants from a simulated nuclear steam generator tube-tubesheet crevice. All testing was performed using a depressurization technique under...

G. E. Von Nieda G. Economy

1981-01-01

417

78 FR 65007 - Inspections, Tests, Analyses, and Acceptance Criteria; Vogtle Electric Generating Plant, Unit 3  

Federal Register 2010, 2011, 2012, 2013

...Generating Plant, Unit 3 AGENCY: Nuclear Regulatory Commission. ACTION: Determination of inspections, tests, analyses, and acceptance...SUMMARY: The U.S. Nuclear Regulatory Commission (NRC...determined that the inspections, tests, and analyses have been...

2013-10-30

418

GMOtrack: generator of cost-effective GMO testing strategies.  

PubMed

Commercialization of numerous genetically modified organisms (GMOs) has already been approved worldwide, and several additional GMOs are in the approval process. Many countries have adopted legislation to deal with GMO-related issues such as food safety, environmental concerns, and consumers' right of choice, making GMO traceability a necessity. The growing extent of GMO testing makes it important to study optimal GMO detection and identification strategies. This paper formally defines the problem of routine laboratory-level GMO tracking as a cost optimization problem, thus proposing a shift from "the same strategy for all samples" to "sample-centered GMO testing strategies." An algorithm (GMOtrack) for finding optimal two-phase (screening-identification) testing strategies is proposed. The advantages of cost optimization with increasing GMO presence on the market are demonstrated, showing that optimization approaches to analytic GMO traceability can result in major cost reductions. The optimal testing strategies are laboratory-dependent, as the costs depend on prior probabilities of local GMO presence, which are exemplified on food and feed samples. The proposed GMOtrack approach, publicly available under the terms of the General Public License, can be extended to other domains where complex testing is involved, such as safety and quality assurance in the food supply chain. PMID:20166592

Novak, Petra Krau; Gruden, Kristina; Morisset, Dany; Lavrac, Nada; Stebih, Dejan; Rotter, Ana; Zel, Jana

2009-01-01

419

Aging and Generational Patterns of Alcohol Consumption among Mexican Americans, Cuban Americans and Mainland Puerto Ricans.  

ERIC Educational Resources Information Center

Used data from Hispanic Health and Nutrition Examination Survey to describe life-course patterns of alcohol consumption among Mexican Americans, Cuban Americans, and Puerto Ricans residing in mainland United States. Found age differences in patterns of consumption among Mexican American and Puerto Rican males that reflect aging effects. Found…

Black, Sandra A.; Markides, Kyriakos S.

1994-01-01

420

Next Generation Weather Radar (NEXRAD) Principal User Processor (PUP) Operational Test and Evaluation (OTE) Operational Test Plan.  

National Technical Information Service (NTIS)

The purpose of this plan is to describe and detail the procedural approach, method, and responsibilities to be employed in conducting the Operational Test and Evaluation (OTE) on the Next Generation Weather Radar (NEXRAD) Principal User Processor (PUP) sy...

B. R. Stretcher

1993-01-01

421

Automated Test Data Generation Using MEA-Graph Planning  

Microsoft Academic Search

With the rapid growth in the development of modern and sophisticated software applications, such as multimodal distributed systems, the complexity of software development processes has increased enormously, posing an urgent need for automation of some of these processes. One of the key software development process is system testing. In This work, we evaluate the potential application of AI planning techniques

Manish Gupta; Farokh B. Bastani; Latifur Khan; I-ling Yen

2004-01-01

422

Using model checking to generate tests from requirements specifications  

Microsoft Academic Search

Recently, many formal methods, such as the SCR (Software Cost Reduction) requirements method, have been proposed for improving the quality of software specifications. Although improved specifications are valuable, the ultimate objective of software development is to produce software that satisfies its requirements. To evaluate the correctness of a software implementation, one can apply black-box testing to determine whether the implementation,

Angelo Gargantinil; Constance L. Heitmeyer

1999-01-01

423

Summary of second generation alpha CAM testing performed at Hanford.  

National Technical Information Service (NTIS)

Pacific Northwest Laboratory and Westinghouse Hanford Company tested six models of commercially available alpha continuous air monitors (CAMs): the Canberra Alpha Sentry, Eberline Alpha 6A-1, Merlin Gerin A-CAM, NE America CAM1A, SAIC/RADeCO Model 452, an...

M. L. Johnson D. R. Sisk R. W. Goles K. L. Swinth M. R. Tinker

1994-01-01

424

Design of personalized test paper generating system of educational telenet based on genetic algorithm  

Microsoft Academic Search

When generating test paper, traditional distant education online examination system either merely extracts the same test questions from item bank or extracts test questions at random, or select test questions according to some classifications of student. It can not individually varies and give custom made scheme according to student's learning situation. This paper improved the traditional genetic algorithm and proposed

Yong Ou-Yang; Hong-Fang Luo

2009-01-01

425

A method of MPEG2TS test stream generation for digital TV software  

Microsoft Academic Search

Input of the digital TV software is a transport stream (TS) in MPEG (Moving Picture Expert Group)-2 format, a standard specification for moving picture compression. We propose a method to thoroughly generate MPEG-2 TS test data, namely, a ‘test stream’ based on the black-box test concept for digital TV software. We also introduce a tool to automate the test stream

Tae-hee Gwak; Byoungju Choi

2004-01-01

426

Parametric Analysis of a Hover Test Vehicle using Advanced Test Generation and Data Analysis  

NASA Technical Reports Server (NTRS)

Large complex aerospace systems are generally validated in regions local to anticipated operating points rather than through characterization of the entire feasible operational envelope of the system. This is due to the large parameter space, and complex, highly coupled nonlinear nature of the different systems that contribute to the performance of the aerospace system. We have addressed the factors deterring such an analysis by applying a combination of technologies to the area of flight envelop assessment. We utilize n-factor (2,3) combinatorial parameter variations to limit the number of cases, but still explore important interactions in the parameter space in a systematic fashion. The data generated is automatically analyzed through a combination of unsupervised learning using a Bayesian multivariate clustering technique (AutoBayes) and supervised learning of critical parameter ranges using the machine-learning tool TAR3, a treatment learner. Covariance analysis with scatter plots and likelihood contours are used to visualize correlations between simulation parameters and simulation results, a task that requires tool support, especially for large and complex models. We present results of simulation experiments for a cold-gas-powered hover test vehicle.

Gundy-Burlet, Karen; Schumann, Johann; Menzies, Tim; Barrett, Tony

2009-01-01

427

DESIGN, FABRICATION, AND TESTING OF AN ADVANCED, NON-POLLUTING TURBINE DRIVE GAS GENERATOR  

SciTech Connect

The objective of this report period was to continue the development of the Gas Generator design, completion of the hardware and ancillary hardware fabrication and commence the Test Preparations for the testing of the non-polluting unique power turbine driven Gas Generator. Focus during this report period has been on completing the Gas Generator fabrication of hardware and ancillary hardware, and completion of unit closeout brazing and bonding. Because of unacceptable delays encountered in a previously competitively selected test site, CES initiated a re-competition of our testing program and selected an alternate test site. Following that selection, CES used all available resources to make preparations for testing the 10 Mw Gas Generator at the new testing site facilities of NTS at Saugus, CA.

E.W. (Gene) Baxter

2002-06-30

428

Improved voltage disturbance generator for the performance test of the custom power devices  

Microsoft Academic Search

An improved voltage disturbance generator is proposed. To test the performance of the custom power devices such as DVR, SSTS, dynamic UPS, etc., a voltage disturbance generator is necessary. The proposed generator has good features of high reliability, low cost, simple structure, high efficiency, and reduced voltage drop. The main switching device is SCR thyristor, and all the thyristors have

Young-Ho Lee; Hae-Young Park; Eui-Cheol Nho; In-Dong Kim; Tae-Won Chun; Heung-Geun Kim; Nam-Sup Choi

2007-01-01

429

Development and testing of a domestic woodstove thermoelectric generator with natural convection cooling  

Microsoft Academic Search

A thermoelectric generator was fitted to the side of a domestic woodstove. The generator was driven using one or more thermoelectric modules designed to give significant power at a reasonable cost. The thermoelectric generator was air cooled by natural convection using a commercially available heat sink. Testing was undertaken under a controlled woodstove firing rate and temperatures, and open circuit

Rida Y. Nuwayhid; Alan Shihadeh; Nesreen Ghaddar

2005-01-01

430

The IEEE Reliability Test System - Extensions to and Evaluation of the Generating System  

Microsoft Academic Search

This paper outlines some of the restrictions which currently exist in the generation data of the IEEE Reliability Test System (RTS). The paper extends the RTS by including more factors and system conditions which may be included in the reliability evaluation of generating systems. These extensions create a wider set of consistent data. The paper also includes generation reliability indices

R. N. Allan; R. Billinton; N. M. K. Abdel-Gawad

1986-01-01

431

Cognitive Operations in the Generation Effect on a Recall Test: Role of Aging and Divided Attention  

ERIC Educational Resources Information Center

Generation effect (generated words are better memorized than read words) of anagrams, rhymes, and associates of target words was examined in young, elderly, and very old subjects. Experiments 1 and 2 showed that only young subjects benefit from the generation effect in a free-recall test when the rule is of a phonological nature. Experiments 3, 4,…

Taconnat, Laurence; Isingrini, Michel

2004-01-01

432

Constraint-based test data generation in the presence of stack-directed pointers  

Microsoft Academic Search

Constraint-Based Test data generation (CBT) exploits constraint satisfaction techniques to generate test data able to kill a given mutant or to reach a selected branch in a program. When pointer variables are present in the program, aliasing problems may arise and may lead to the failure of current CBT approaches. In our work, we propose an overall CBT method that

Arnaud Gotlieb; Tristan Denmat; Bernard Botella

2005-01-01

433

Short-circuit tests on a high-voltage, cable-wound hydropower generator  

Microsoft Academic Search

Data from measurements on the first Powerformer generator installed in Porjus, Sweden, will be presented. The generator has a rating of 45 kV and 11 MVA. In total, the machine has been running more than 13700 h (October 2001) and has been exposed to a number of different tests including short-circuit tests on the terminal at 100% magnetization. Experience and

Stefan G. Johansson; Bertil Larsson

2004-01-01

434

Some Implications of MSC, SDL and TTCN Time Extensions for Computer-Aided Test Generation  

Microsoft Academic Search

The purpose of this paper is to describe how computer-aided test generation methods can benet from the time features and exten- sions to MSC, SDL and TTCN which are either already available or currently under study in the EC Interval project. The implications for currently available test generation tools are shown and proposals for their improvement are made. The transformation

Dieter Hogrefe; Beat Koch; Helmut Neukirchen

2001-01-01

435

On the Generation of Test Data for Prolog by Partial Evaluation  

Microsoft Academic Search

In recent work, we have proposed an approach to Test Data Generation (TDG) of imperative bytecode by partial evaluation (PE) of CLP which consists in two phases: (1) the bytecode program is first transformed into an equivalent CLP program by means of interpretive compilation by PE, (2) a second PE is performed in order to supervise the generation of test-cases

Miguel Gomez-Zamalloa; Elvira Albert; German Puebla

2009-01-01

436

Generating Event Sequence-Based Test Cases Using GUI Runtime State Feedback  

Microsoft Academic Search

This paper presents a fully automatic model-driven technique to generate test cases for graphical user interfaces (GUIs)-based applications. The technique uses feedback from the execution of a ??seed test suite,?? which is generated automatically using an existing structural event interaction graph model of the GUI. During its execution, the runtime effect of each GUI event on all other events pinpoints

Xun Yuan; Atif M. Memon

2010-01-01

437

Instructional Topics in Educational Measurement (ITEMS) Module: Using Automated Processes to Generate Test Items  

ERIC Educational Resources Information Center

Changes to the design and development of our educational assessments are resulting in the unprecedented demand for a large and continuous supply of content-specific test items. One way to address this growing demand is with automatic item generation (AIG). AIG is the process of using item models to generate test items with the aid of computer…

Gierl, Mark J.; Lai, Hollis

2013-01-01

438

Large Current Lightning Mimic Test for FRP Blades of Wind Turbine Generators  

Microsoft Academic Search

In Japan, lightning damage to FRP blades of wind turbine generators has been increasing in parallel with the recent increase in the installation of wind turbine generators. Therefore, we established a test method, while clarifying the destructive climate of lightning, and examined a method of preventing destruction. A high-voltage test clearly showed that lightning easily penetrates FRP that is not

Masahiro Hanai; Hisatoshi Ikeda; Masumi Nakadate; Haruo Sakamoto

2007-01-01

439

Patterns of Various ESOL Proficiency Test Scores by Native Language and Proficiency Levels. Occasional Papers on Linguistics, No. 1.  

ERIC Educational Resources Information Center

A profile method was used to analyze the patterns of four English proficiency tests (Comprehensive English Language Test for Speakers of English as a Second Language: Structure, CELT: Listening, Reading for Understanding Test, and The New Cloze Test) regarding two examinee characteristics: their language proficiency levels and native language. One…

Hisama, Kay K.

440

Direct imaging of periodic subwavelength patterns generated by optical phase masks  

SciTech Connect

We have demonstrated direct imaging of interference fringes of total atomic density with periods {lambda}/4 and {lambda}/2 for optical wavelength {lambda} that have been produced in a de Broglie wave atom interferometer. The imaging was done by means of an 'optical mask' technique, which allowed us to observe subwavelength periodic patterns with a resolution of up to {lambda}/16. In addition, the dependence of the fringe pattern on the recoil phase and pulse area reveals quantum dynamics in the atomic center-of-mass motion. The behavior of the fringe patterns near the interference times distinguishes the effects of phase gratings from those of amplitude gratings.

Tonyushkin, Alexei; Sleator, Tycho [Department of Physics, New York University, 4 Washington Place, New York, New York 10003 (United States)

2006-11-15

441

Coincident steam generator tube rupture and stuck-open safety relief valve carryover tests: MB-2 steam generator transient response test program  

SciTech Connect

In PWR steam generator tube rupture (SGTR) faults, a direct pathway for the release of radioactive fission products can exist if there is a coincident stuck-open safety relief valve (SORV) or if the safety relief valve is cycled. In addition to the release of fission products from the bulk steam generator water by moisture carryover, there exists the possibility that some primary coolant may be released without having first mixed with the bulk water - a process called primary coolant bypassing. The MB-2 Phase II test program was designed specifically to identify the processes for droplet carryover during SGTR faults and to provide data of sufficient accuracy for use in developing physical models and computer codes to describe activity release. The test program consisted of sixteen separate tests designed to cover a range of steady-state and transient fault conditions. These included a full SGTR/SORV transient simulation, two SGTR overfill tests, ten steady-state SGTR tests at water levels ranging from very low levels in the bundle up to those when the dryer was flooded, and three moisture carryover tests without SGTR. In these tests the influence of break location and the effect of bypassing the dryer were also studied. In a final test the behavior with respect to aerosol particles in a dry steam generator, appropriate to a severe accident fault, was investigated.

Garbett, K.; Mendler, O.J.; Gardner, G.C.; Garnsey, R.; Young, M.Y.

1987-03-01

442

Functional test generation for digital circuits described with a declarative language: LUSTRE  

NASA Astrophysics Data System (ADS)

A functional approach to the test generation problem starting from a high level description is proposed. The circuit tested is modeled, using the LUSTRE high level data flow description language. The different LUSTRE primitives are translated to a SATAN format graph in order to evaluate the testability of the circuit and to generate test sequences. Another method of testing the complex circuits comprising an operative part and a control part is defined. It consists of checking experiments for the control part observed through the operative part. It was applied to the automata generated from a LUSTRE description of the circuit.

Almahrous, Mazen

1990-08-01

443

Summary of DEEP STEAM downhole steam generator development activities. [Kern River and Long Beach field tests  

SciTech Connect

In this paper the concept and goals of the DOE program, DEEP STEAM, as related to the development of a downhole steam generator for deep heavy oil recovery will be discussed. Additionally, the past, present and future activities of the development program being carried out at Sandia National Laboratories will be discussed. These include evaluation studies, surface testing at Bakersfield, CA, a run-in test at Hobbs, NM, and status of field testing at Long Beach, CA. The Long Beach test includes both a downhole diesel-air generator and a surface diesel-oxygen generator. 7 figures.

Donaldson, A.B.; Fox, R.L.; Mulac, A.J.

1981-01-01

444

Magnetic Patterning of Permanent-Magnet Rotors for Microscale Motor/Generators.  

National Technical Information Service (NTIS)

We present and characterize a process to pattern magnetic poles on small permanent-magnet (PM) rotors used in microscale, axial-flux, PM machines. Unlike other previously reported approaches, this approach uses a ferromagnetic magnetizing head (MH) and an...

D. P. Arnold F. Herrault I. Zana M. G. Allen

2005-01-01

445

Models for the Generation of the Motor Output Pattern in Flying Locusts.  

National Technical Information Service (NTIS)

The motor output to the flight muscles of flying locusts is described briefly. Model neural networks that simulate many aspects of this output pattern are discussed. The model networks studied consisted of interconnected electronic analogs of unit patches...

D. M. Wilson I. Waldron

1967-01-01

446

Generation of functional eggs and sperm from cryopreserved whole testes.  

PubMed

The conservation of endangered fish is of critical importance. Cryobanking could provide an effective backup measure for use in conjunction with the conservation of natural populations; however, methodology for cryopreservation of fish eggs and embryos has not yet been developed. The present study established a methodology capable of deriving functional eggs and sperm from frozen type A spermatogonia (ASGs). Whole testes taken from rainbow trout were slowly frozen in a cryomedium, and the viability of ASGs within these testes did not decrease over a 728-d freezing period. Frozen-thawed ASGs that were intraperitoneally transplanted into sterile triploid hatchlings migrated toward, and were incorporated into, recipient genital ridges. Transplantability of ASGs did not decrease after as much as 939 d of cryopreservation. Nearly half of triploid recipients produced functional eggs or sperm derived from the frozen ASGs and displayed high fecundity. Fertilization of resultant gametes resulted in the successful production of normal, frozen ASG-derived offspring. Feasibility and simplicity of this methodology will call for an immediate application for real conservation of endangered wild salmonids. PMID:23319620

Lee, Seungki; Iwasaki, Yoshiko; Shikina, Shinya; Yoshizaki, Goro

2013-01-29

447

Evaluation of attenuated PSM photomask blanks with TF11 chrome and FEP-171 resist on a 248 nm DUV laser pattern generator  

NASA Astrophysics Data System (ADS)

Tighter requirements on mask resolution, CD and image positioning accuracy at and beyond the 45 nm technology node push the development of improved photomask blanks. One such blank for attenuated phase-shift masks (att-PSM) provides a thinner chrome film, named TF11, with higher chrome etch rate compared to the previous generation Att- PSM blank (NTAR5 chrome film) from the same supplier. Reduced stress in the chrome film also results in less image placement error induced by the material. FEP-171 is the positive chemically amplified resist (PCAR) that is most commonly used in advanced mask manufacturing with both 50 keV variable shaped e-beam (VSB) and DUV laser pattern generators. TF11 allows an FEP-171 resist film down to about 2000 Å thickness with sufficient etch resistance, while the standard resist thickness for NTAR5 is around 3000 Å. This work has experimentally evaluated the use of TF11 chrome and FEP-171 resist together with a 248 nm DUV laser pattern generator, the Sigma7500. First, patterning performance in resist with thicknesses from 2000 Å to 2600 Å, in steps of 100 Å, was tested with respect to swing curve and basic lithographic parameters including resolution, CD linearity, CD iso-dense bias and dose sensitivity. Patterning results on mask showed a swing minimum at around 2200 Å and a swing maximum at around 2500 Å, which correspond to reflectivity measurements for 248 nm wavelength performed by the blank supplier. It was concluded that the overall patterning performance was best close to the swing maximum. Thereafter the patterning performance using TF11 at two resist thicknesses, 2000 Å and 2550 Å, was studied in more detail and compared to performance using NTAR5 with 3200 Å resist. The evaluation showed that the Sigma7500-II offers good compatibility with TF11, especially using the optimized FEP-171 resist thickness of 2550 Å. It also showed that the patterning capability of the Sigma7500-II using TF11 and 2550 Å resist is improved compared to using NTAR5 and 3200 Å resist.

Xing, Kezhao; Björnborg, Charles; Karlsson, Henrik; Paulsson, Adisa; Rosendahl, Anna; Beiming, Peter; Vedenpää, Jukka; Walford, Jonathan; Newman, Tom

2007-10-01

448

Generation and Testing of Autonomous Mineral Detectors for Mars Rovers  

NASA Astrophysics Data System (ADS)

Currently Mars missions can collect more data than can be returned. Autonomous systems for data collection, processing and return will aid future Mars rovers in prioritizing and returning geologically important information. We have created a neural net detector that is able to successfully recognize carbonates from Visible/NIR (350-2500 nm) spectra of rocks collected from Mars analog environments (Gilmore et al. JGR 105, 29,223). In order to characterize and improve the detector's sensitivity, we are evaluating the performance of the detector under more realistic Martian environments: 1) carbonate minerals covered with palagonitic dust, and 2) carbonate minerals intimately mixed with basalt and palagonite. Lessons learned will be applied to the generation of additional detectors for minerals of interest (e.g., hydrothermal minerals). Aliquots of Martian Soil Simulant JSC Mars-1 palagonite were sieved to <45 microns and air fall deposited onto a calcite crystal and an adjacent glass slide. Spectra in the Vis/NIR were taken of the calcite after every layer up to a thickness of 270 microns (35 layers) with an Analytical Spectral Devices Field Spec Pro spectrometer operating from 350-2500 nm. The carbonate detector, operating over the range 2000-2400 nm, has an empirically established detection threshold based on training with thousands of synthetic linear combinations of laboratory mineral spectra designed to simulate expected Martian rocks. The detection threshold was reached in this experiment when the dust layer thickness reached 102 -116 microns (78-85% aerial coverage). This corresponds to a real change in the depth of the 2300 nm carbonate band (continuum depth, D= 1- [reflectance at trough center/reflectance at continuum] = ~0.1), and is similar to the detection threshold of the human experimenter. Very thin (~10-20 microns) coatings of palagonite dust had a large effect on the spectral response of the substrate, exemplifying the nonlinear mixing of the two components. We will report on experiments mixing known quantities of carbonate with basalt and palagonite at various grain sizes. We plan to assess the detector's ability to discern and quantify varying amounts of carbonate within the mixtures, and model the spectra as nonlinear mixtures to ascertain if any improvements in the accuracy of the neural net can be achieved. Finally, we will report on the generation and performance of a detector capable of identifying phyllosilicate minerals individually and as a mineral class.

Merrill, M. D.; Gilmore, M. S.; Castaño, R.; Bornstein, B.; Greenwood, J.

2004-05-01

449

Generation of spatiotemporal calcium patterns by coupling a pH-oscillator to a complexation equilibrium.  

PubMed

Sustained spatiotemporal pH and calcium patterns are produced in a non-equilibrium inorganic reaction-diffusion system by coupling two modules, the bromate-sulfite-ferrocyanide pH-oscillator and the pH-sensitive complexation of Ca(2+) by ethylenediaminetetraacetate. The development of chemical waves is mainly determined by the oscillatory module, however, the formation of the localised stationary patterns results in the synergistic interaction between the modules. PMID:24590180

Molnár, István; Kurin-Csörgei, Krisztina; Orbán, Miklós; Szalai, István

2014-04-25

450

Automatic Generation of Rasch-Calibrated Items: Figural Matrices Test GEOM and Endless-Loops Test EC  

ERIC Educational Resources Information Center

The future of test construction for certain psychological ability domains that can be analyzed well in a structured manner may lie--at the very least for reasons of test security--in the field of automatic item generation. In this context, a question that has not been explicitly addressed is whether it is possible to embed an item response theory…

Arendasy, Martin

2005-01-01

451

Next-generation genetic testing for retinitis pigmentosa  

PubMed Central

Molecular diagnostics for patients with retinitis pigmentosa (RP) has been hampered by extreme genetic and clinical heterogeneity, with 52 causative genes known to date. Here, we developed a comprehensive next-generation sequencing (NGS) approach for the clinical molecular diagnostics of RP. All known inherited retinal disease genes (n = 111) were captured and simultaneously analyzed using NGS in 100 RP patients without a molecular diagnosis. A systematic data analysis pipeline was developed and validated to prioritize and predict the pathogenicity of all genetic variants identified in each patient, which enabled us to reduce the number of potential pathogenic variants from approximately 1,200 to zero to nine per patient. Subsequent segregation analysis and in silico predictions of pathogenicity resulted in a molecular diagnosis in 36 RP patients, comprising 27 recessive, six dominant, and three X-linked cases. Intriguingly, De novo mutations were present in at least three out of 28 isolated cases with causative mutations. This study demonstrates the enormous potential and clinical utility of NGS in molecular diagnosis of genetically heterogeneous diseases such as RP. De novo dominant mutations appear to play a significant role in patients with isolated RP, having major implications for genetic counselling.

Neveling, Kornelia; Collin, Rob W.J.; Gilissen, Christian; van Huet, Ramon A.C.; Visser, Linda; Kwint, Michael P.; Gijsen, Sabine J.; Zonneveld, Marijke N.; Wieskamp, Nienke; de Ligt, Joep; Siemiatkowska, Anna M.; Hoefsloot, Lies H.; Buckley, Michael F.; Kellner, Ulrich; Branham, Kari E.; den Hollander, Anneke I.; Hoischen, Alexander; Hoyng, Carel; Klevering, B. Jeroen; van den Born, L. Ingeborgh; Veltman, Joris A.; Cremers, Frans P.M.; Scheffer, Hans

2012-01-01

452