scholarly journals Korat: A Tool for Generating Structurally Complex Test Inputs

Author(s):  
Aleksandar Milicevic ◽  
Sasa Misailovic ◽  
Darko Marinov ◽  
Sarfraz Khurshid
Keyword(s):  
Author(s):  
Anne E. Gattiker ◽  
Phil Nigh ◽  
Wojciech Maly

Abstract This article provides an analysis of a class of failures observed during the SEMATECH-sponsored Test Methods Experiment. The analysis focuses on use of test-based failure analysis and IDDQ signature analysis to gain insight into the physical mechanisms underlying such subtle failures. In doing so, the analysis highlights techniques for understanding failure mechanisms using only tester data. In the experiment, multiple test methods were applied to a 0.45 micrometer effective channel length ASIC. Specifically, ICs that change test behavior from before to after burn-in are studied to understand the physical nature of the mechanism underlying their failure. Examples of the insights provided by the test-based analysis include identifying cases where there are multiple or complex defects and distinguishing cases where the defect type is likely to be a short versus an open and determining if the defect is marginal. These insights can be helpful for successful failure analysis.


1982 ◽  
Vol 28 (9) ◽  
pp. 1887-1893 ◽  
Author(s):  
D F Ranney ◽  
A J Quattrone

Abstract Several common metabolites and drugs in the serum in of patients with inflammatory, infectious, autoimmune, immunodeficient, neoplastic, and toxicant-induced diseases can produce artifactual suppression of the [methyl-3H]-thymidine assay, which is widely used to evaluate lymphocyte responsiveness. We have developed a sensitive, semiautomated, fluorescence-enhancement assay in which true immunosuppressors are measured in the presence of absence of such interfering substances. Peripheral blood lymphocytes are activated with mitogens in standard microtiter culture trays. Changes in lymphocyte DNA content are quantified with a reagent formulation containing mithramycin, the fluorescence of which is enhanced on binding to DNA in the presence of MgCl2. We solubilize cells within the intact microtiter tray by using an automated, inverted "Array Sonicator," and measure fluorescence with an automated, photon-counting fluorometer. With this system, immune response modulation can be accurately assessed in the presence of patients' sera and other complex test substances (e.g., supernates from hybridomas, fermentation vats, viral preparations, and macrophage cultures.


1977 ◽  
Vol 44 (2) ◽  
pp. 551-562
Author(s):  
Edmund R. Goedert ◽  
Albert S. Rodwan ◽  
Paul G. Salmon

There is evidence for discrete property analyzers in mammalian visual systems. Research has indicated that prolonged stimulation of such units reduces their sensitivity to subsequent stimulation. Psychophysical studies have employed this effect, termed selective adaptation, to study feature extractors in the human visual system. The purpose of this study was to determine the role of density and deviation in the adaptation figure on the recognition thresholds of simple and complex test figures. A selective adaptation paradigm was employed. A strict property analyzer model suggests that increases in density, deviation, or complexity should lead to an increased recognition time for the test figures. This was not confirmed. The complexity of the test figure had no effect on its recognition time. Both increased density and deviation did have an effect on the recognition times of the test figures. The results thus suggest that contour adaptation involves at least two processes: a general, probably peripheral effect due to the fatigue of visual receptor units and a more specific effect generated by the similarity between test figure and adaptation contours, independent of the site of stimulation.


Author(s):  
T. J. Pitkänen ◽  
E. A. Mäntysaari ◽  
U. S. Nielsen ◽  
G. P. Aamand ◽  
P. Madsen ◽  
...  
Keyword(s):  

2020 ◽  
pp. 79-103
Author(s):  
Alexander Malyshev ◽  
Evgenii Burgov

Using bioinspired models and methods is one of approaches for solving tasks of swarm robotics. In this paper one of such tasks, modeling of foraging, and it’s solving by creating analogues of social structures of ants and models of feeding behavior are considered. The most important characteristics of ants’ colonies for modeling were defined – individuals number in society and it’s structure, workers’ speed, a communication distance and working area size. Besides, existing experimental basis (a group of robots and a polygon) was estimated for a usage as a hardware platform for experiments. Several models of feeding behavior were considered: a model without foragers’ functions differentiation and a model with differentiation on active and passive ones. Active foragers look for resources by themselves, then they involve passive foragers; passive foragers are settled on a base, while are not involved in harvesting. A set of finite state machines describe the behavior of agents: basic automatons (provide basic behavior functions) and a meta- automaton, that switches with some conditions an execution of basic automatons. Basic movements were tested on experimental basis. A complex test of models were conducted in a simulation program Kvorum. An analogue of real polygon was made in the program. Modeling consists of series of experiments for every model in which agents must harvest resources. Series differ from each other by number of agents. For models’ quality estimation a ratio of received energy to average obtaining time. Experiments settle that model with functions differentiation works more effective.


Author(s):  
Stefan Riedelmeier ◽  
Stefan Becker ◽  
Eberhard Schlücker

For the analysis of the effects of fluid-structure interaction (FSI) during water hammer in piping systems, a complex test facility was constructed. Resonance experiments with movable bends in two system configurations were carried out. The pressure and the displacement of the bend were recorded. The aim was to reproduce the results with two coupled codes: a one-dimensional solver based on the method of characteristics (MOC) for the hydraulic system and a three-dimensional solver based on the finite element method (FEM) working with one-dimensional beam elements for the structural system. The calculation included junction and friction coupling. The models were fine-tuned separately. For this purpose, special measurements were carried out. These included the determination of the structural damping, the friction factor, the influence of the bending of the anchorage, etc. After the validation of the models, the results of the coupled calculations were compared against the measurements, the performance of the coupled codes was evaluated and the most important physical effects were analyzed and are discussed.


Author(s):  
Sebastien Gueydon

Abstract With their light weights, small components like braces and heave plates and steady trim angle caused by the wind loads acting on the rotor, semisubmersible foundations used as support platform for wind turbines exhibit a complex behaviour where viscous loading play an important role. The work done by the Offshore Code Comparison Collaboration Continued with Correlation (OC5) project has shown that standard engineering tools were not always able to predict accurately the motions of the DeepCwind semisubmersible that were measured in a basin. The correct amplitude of the motions at the natural periods of this system appeared to be difficult to obtain with simulations (especially the low frequency surge, and the pitch resonant motion). In view of the complexity of the system, it was not possible to clearly identify the causes of the differences between the simulations and the model-test results. A follow-on validation campaign was therefore performed at the Maritime Research Institute Netherlands (MARIN) under the MARINET2 project with the same floating substructure, with a focus on better understanding the hydrodynamic loads and reducing uncertainty in the tests by minimizing the system complexity. The wind turbine was replaced by a stiff tower with resembling inertia properties. The mooring system was simplified by using taut-spring lines with equivalent linear stiffness in surge. This paper reviews the new tests done with the simplified set-up and examines the differences with previous tests done with more complex test set-ups. The main motivation of this work is to study how variations of an experimental set-up can affect the outcome of tests in a wave basin. To start with, the main parameters of the systems (inertia, hydrostatics, and mooring stiffness) for all set-ups are characterized to check how similar they are. Then the level of damping in all systems is compared. Finally, the paper looks at how well the motion responses of this semisubmersible in waves correlate between all these campaigns.


2019 ◽  
Vol 44 (6) ◽  
pp. 671-705 ◽  
Author(s):  
Matthias von Davier ◽  
Lale Khorramdel ◽  
Qiwei He ◽  
Hyo Jeong Shin ◽  
Haiwen Chen

International large-scale assessments (ILSAs) transitioned from paper-based assessments to computer-based assessments (CBAs) facilitating the use of new item types and more effective data collection tools. This allows implementation of more complex test designs and to collect process and response time (RT) data. These new data types can be used to improve data quality and the accuracy of test scores obtained through latent regression (population) models. However, the move to a CBA also poses challenges for comparability and trend measurement, one of the major goals in ISLAs. We provide an overview of current methods used in ILSAs to examine and assure the comparability of data across different assessment modes and methods that improve the accuracy of test scores by making use of new data types provided by a CBA.


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