389,887 research outputs found

    Checking experiment design methods

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    Tento dokument obsahuje přehled testovacích metod konečně-stavových automatů. Testovací metoda kontroluje zda se nějaký automat shoduje s daným automatem. Nová metoda je představena a následně experimentálně prokázána, že je korektní testovací metodou. Dokument dále obsahuje klasifikaci konečně-stavových automatů, algoritmy konstruující separující sekvence a nový přístup kontrolování, zda je metoda korektní testovací metodou. Separující sekvence rozlišuje dva stavy automatu, se kterými souvisí.This document is an overview of testing methods of finite-state machines. Testing methods verifies whether a machine coincides with given one. A new method is proposed and it is demonstrated to be correct testing method of finite-state machines experimentally. The document further comprises classification of finite-state machines, algorithms for creating separating sequences and a new approach to checking testing methods to be correct. A separating sequence relates to a pair of states. Such two states are distinguished by the separating sequence

    Acoustic emission frequency discrimination

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    In acoustic emission nondestructive testing, broadband frequency noise is distinguished from narrow banded acoustic emission signals, since the latter are valid events indicative of structural flaws in the material being examined. This is accomplished by separating out those signals which contain frequency components both within and beyond (either above or below) the range of valid acoustic emission events. Application to acoustic emission monitoring during nondestructive bond verification and proof loading of undensified tiles on the Space Shuttle Orbiter is considered

    Functional Testing Approaches for "BIFST-able" tlm_fifo

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    Evolution of Electronic System Level design methodologies, allows a wider use of Transaction-Level Modeling (TLM). TLM is a high-level approach to modeling digital systems that emphasizes on separating communications among modules from the details of functional units. This paper explores different functional testing approaches for the implementation of Built-in Functional Self Test facilities in the TLM primitive channel tlm_fifo. In particular, it focuses on three different test approaches based on a finite state machine model of tlm_fifo, functional fault models, and march tests respectivel

    Preprototype nitrogen supply subsystem development

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    The design and development of a test stand for the Nitrogen Generation Module (NGM) and a series of tests which verified its operation and performance capability are described. Over 900 hours of parametric testing were achieved. The results from this testing were then used to design an advanced NGM and a self contained, preprototype Nitrogen Supply Subsystem. The NGM consists of three major components: nitrogen generation module, pressure controller and hydrazine storage tank and ancillary components. The most important improvement is the elimination of all sealing surfaces, achieved with a total welded or brazed construction. Additionally, performance was improved by increasing hydrogen separating capability by 20% with no increase in overall packaging size

    Time-of-flight discrimination between gamma-rays and neutrons by neural networks

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    In gamma-ray spectroscopy, a number of neutrons are emitted from the nuclei together with the gamma-rays and these neutrons influence gamma-ray spectra. An obvious method of separating between neutrons and gamma-rays is based on the time-of-flight (tof) technique. This work aims obtaining tof distributions of gamma-rays and neutrons by using feed-forward artificial neural network (ANN). It was shown that, ANN can correctly classify gamma-ray and neutron events. Testing of trained networks on experimental data clearly shows up tof discrimination of gamma-rays and neutrons.Comment: 10 pages, 8 figure

    Fabrication of fuel pin assemblies, phase 3

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    Five full size and eight reduced length fuel pins were fabricated for irradiation testing to evaluate design concepts for a fast spectrum lithium cooled compact space power reactor. These assemblies consisted of uranium mononitride fuel pellets encased in a T-111 (Ta-8W-2Hf) clad with a tungsten barrier separating fuel and clad. Fabrication procedures were fully qualified by process development and assembly qualification tests. Detailed specifications and procedures were written for the fabrication and assembly of prototype fuel pins
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