511 research outputs found
Noise correction on LANDSAT images using a spline-like algorithm
Many applications using LANDSAT images face a dilemma: the user needs a certain scene (for example, a flooded region), but that particular image may present interference or noise in form of horizontal stripes. During automatic analysis, this interference or noise may cause false readings of the region of interest. In order to minimize this interference or noise, many solutions are used, for instane, that of using the average (simple or weighted) values of the neighboring vertical points. In the case of high interference (more than one adjacent line lost) the method of averages may not suit the desired purpose. The solution proposed is to use a spline-like algorithm (weighted splines). This type of interpolation is simple to be computer implemented, fast, uses only four points in each interval, and eliminates the necessity of solving a linear equation system. In the normal mode of operation, the first and second derivatives of the solution function are continuous and determined by data points, as in cubic splines. It is possible, however, to impose the values of the first derivatives, in order to account for shapr boundaries, without increasing the computational effort. Some examples using the proposed method are also shown
A procedure for testing the quality of LANDSAT atmospheric correction algorithms
There are two basic methods for testing the quality of an algorithm to minimize atmospheric effects on LANDSAT imagery: (1) test the results a posteriori, using ground truth or control points; (2) use a method based on image data plus estimation of additional ground and/or atmospheric parameters. A procedure based on the second method is described. In order to select the parameters, initially the image contrast is examined for a series of parameter combinations. The contrast improves for better corrections. In addition the correlation coefficient between two subimages, taken at different times, of the same scene is used for parameter's selection. The regions to be correlated should not have changed considerably in time. A few examples using this proposed procedure are presented
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A Model of Practice Related Shifts in the Locus of Brain Activity During Verbal Response Selection Tasks
Recent Positron Emission Tomography (PET) and other
studies have produced detailed information about the
areas of the brain involved in word association tasks,
their functional roles in learning word associations, and
the changes in activity in these areas during learning.
We present a dynamic neurond model that replicates
observed human cognitive behavior in learning word as?sociations while satisfying salient neuroanatomical and
neuropsychological constraints. The model captures the
observed dynamics of cortico-thalamo-basal ganglionic
loops
Evaluation of new insecticide molecules for their effectiveness in the management of sugarcane early shoot borer, Chilo infuscatellus (Snellen)
An experiment was conducted at Zonal Agricultural Research Station, V.C farm, Mandya (Karnataka), India during 2015, to assess the chemical control of sugarcane early shoot borer (Chilo infuscatellus). Nine insecticides namely, Fipronil 0.3G, Chlorantraniliprole 0.4G, Chlorantraniliprole 18.5 SC, Spinosad 45SC, Flubendiamide 39.35SC, Cartap hydrochloride 4G, Phorate 10G, Carbofuran 3G, Chlorpyriphos 20EC, and compared with untreated (Check plot)using randomized block design with three replications. Significant differences were noticed among the treatments. Chlorantraniliprole 0.4G recorded lowest cumulative incidence (2.79 %) and highest per cent reduction over the control (85.78 %) which was followed by Cartap hydrochloride 4G (5.37% and 72.65%), Chlorantraniliprole 18.5 SC (5.95% and 75.62%), Flubendiamide 39.35SC (6.64% and 66.19%) and Fipronil 0.3G (6.83% and 65.22%) were found significantly superior in reducing the cumulative incidence of C. infuscatellus.In Co 86032 Cartap hydrochloride 4G was found to be the best insecticide in getting a highest cost benefit ratio (1:12.39). Other insecticides such as Fipronil 0.3G (1:8.84), Chlorantraniliprole 0.4G (1:6.96), Flubendiamide 39.35SC (1:5.42) and Spinosad 45SC (1:4.16) have also recorded better cost benefit ratio. Since Cartap hydrochloride 4G does not have crop label so we can recommend Fipronil 0.3G or Chlorantraniliprole 0.4G for the management of sugarcane early shoot borer
Establishing a Search String to Detect Secondary Studies in Software Engineering
Search for secondary studies is essential to establish whether the review on
the intended topic has already been done, avoiding waste time. In addition,
secondary studies are the inputs of a tertiary study. However, one critical
step in searching for secondary studies is to elaborate a search string. The
main goal of this work is to analyze search strings to establish directions to
better detect secondary studies in Software Engineering (SE). We analyzed seven
tertiary studies under two perspectives: (1) structure - strings' terms to
detect secondary studies; and (2) field: where searching - titles alone or
abstracts alone or titles and abstracts together, among others. We also
performed a validation of the results found. The suitable search string for
finding secondary studies in SE contain the terms "systematic review",
"literature review", "systematic mapping", "mapping study", "systematic map",
"meta-analysis", "survey" and "literature analysis". Furthermore, we recommend
(1) researchers use the title, abstract and keywords search fields in their
searches to increase studies recall; (2) researchers choose carefully their
paper title, abstract and keyword terms to increase the chance of having such
studies found on digital libraries
Probing the physiology of ASH neuron in Caenorhabditis elegans using electric current stimulation
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98694/1/ApplPhysLett_99_053702.pd
Single-particle fluctuations and directional correlations in driven hard-sphere glasses
A System for Fault Management and Fault Consequences Analysis for NASA's Deep Space Habitat
NASA's exploration program envisions the utilization of a Deep Space Habitat (DSH) for human exploration of the space environment in the vicinity of Mars and/or asteroids. Communication latencies with ground control of as long as 20+ minutes make it imperative that DSH operations be highly autonomous, as any telemetry-based detection of a systems problem on Earth could well occur too late to assist the crew with the problem. A DSH-based development program has been initiated to develop and test the automation technologies necessary to support highly autonomous DSH operations. One such technology is a fault management tool to support performance monitoring of vehicle systems operations and to assist with real-time decision making in connection with operational anomalies and failures. Toward that end, we are developing Advanced Caution and Warning System (ACAWS), a tool that combines dynamic and interactive graphical representations of spacecraft systems, systems modeling, automated diagnostic analysis and root cause identification, system and mission impact assessment, and mitigation procedure identification to help spacecraft operators (both flight controllers and crew) understand and respond to anomalies more effectively. In this paper, we describe four major architecture elements of ACAWS: Anomaly Detection, Fault Isolation, System Effects Analysis, and Graphic User Interface (GUI), and how these elements work in concert with each other and with other tools to provide fault management support to both the controllers and crew. We then describe recent evaluations and tests of ACAWS on the DSH testbed. The results of these tests support the feasibility and strength of our approach to failure management automation and enhanced operational autonom
A Practical Approach for Automated Test Case Generation using Statecharts
This paper presents an approach for automated test case generation using a software specification modeled in Statecharts. The steps defined in such approach involve: translation of Statecharts modeling into an XML-based language; and the PerformCharts tool generates FSMs based on control flow. These FSMs are the inputs for the Condado tool which generates test cases. The idea is to demonstrate that by using a higher-level technique, such as Statecharts, complex software can be represented with clarity and rich details. A case study was on an implementation of a protocol specified for communication between a scientific experiment and the On-Board Data Handling Computer of a satellite under development at Nationa
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