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Digital Data (digital + data)
Selected AbstractsCOMPARISON OF HSPF OUTPUTS USING FTABLES GENERATED WITH FIELD SURVEY AND DIGITAL DATA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2006Nathan Staley ABSTRACT: The Hydrological Simulation Program-FORTRAN (HSPF) describes discharge from a stream reach based on function tables (FTABLES) that relate stream stage, surface area, volume, and discharge. For this study, five FTABLE scenarios were compared to assess their effect on daily discharge rates predicted using HSPF. Four "field-based" FTABLE scenarios were developed using detailed cross section surveys collected at predefined intervals along 14 reaches in the study watershed. A fifth "digital-based" scenario was developed using digital elevation models (DEMs) and Natural Resource Conservation Service (NRCS) Regional Hydraulic Geometry Curves. The Smirnov k-sample test was used to compare average daily discharge rates simulated with HSPF using the five FTABLE scenarios. No significant difference in simulated stream discharge was found (p = 0.99) between the five FTABLE scenarios. Additional examination of the four field-based scenarios revealed that the number of cross sections per stream reach used to generate FTABLES had little effect on the resulting stage discharge relationship. These findings suggest that FTABLES generated using digital data are a viable option when simulating stream discharge with HSPF and that if field data are used to generate FTABLES, using fewer cross sections will not adversely affect simulated discharge predictions. [source] A portable system for continuous monitoring of bird nests using digital video recordersJOURNAL OF FIELD ORNITHOLOGY, Issue 3 2007Andrew J. Pierce ABSTRACT A variety of photographic methods have been described for monitoring nest predation. All have limitations for studying active nests in remote situations, such as size, expense, volume of data recorded, and types of trigger mechanisms. We developed a digital video surveillance system using infrared cameras to monitor predation at bird nests. The main advantage of this system over other video recorders is the small size of the recorder that can run continuously at 29 frames/s for more than 3 days. The recorder's built-in monitor makes it more transportable and allows for easy setup. Digital data is compact, can be reviewed quickly, and requires less physical storage space than videotapes. We recorded nest predation by mammals, birds, and snakes as well as egg and nestling losses not caused by predation. System failure rates were low and the total cost was comparable to ($700 US) video cassette recorders that are often used to monitor nests. SINOPSIS Se han descrito una gran variedad de métodos fotográficos para monitorear la depredación de nidos. Todos los métodos tienen limitaciones para estudiar nidos activos a distancia, como su tamaño, costo, volumen de los datos grabados y mecanismos para activar el equipo. Desarrollamos un sistema digital de vigilancia, utilizando cámaras infrarrojas para monitorear la depredación de nidos. La ventaja principal de este equipo sobre otros similares es el tamaño de la grabadora, la cual puede funcionar continuamente a 29 cuadros/s por más de tres días. El monitor integrado a la cámara hace que el equipo que sea más fácil de transportar y permite que se pueda montar con facilidad. Los datos digitales son compactos, se pueden revisar rápidamente, y requieren menos espacio de almacenaje que las cintas de video convencionales. Grabamos depredación de nidos por mamíferos, aves y culebras al igual que la pérdida de huevos y pichones por otras causas. La tasa de malfuncionamiento fue baja y el costo del equipo ($700 US) es comparable a otros equipos de videograbación a cassette que se utilizan frecuentemente para monitorear nidos. [source] Modelling the distribution of badgers Meles meles: comparing predictions from field-based and remotely derived habitat dataMAMMAL REVIEW, Issue 1 2007GERALDINE NEWTON-CROSS ABSTRACT 1Environmental heterogeneity is important in determining the distribution and abundance of organisms at various spatial scales. The ability to understand and predict distribution patterns is important for solving many management problems in conservation biology and wildlife epidemiology. 2The badger Meles meles is a highly adaptable, medium-sized carnivore, distributed throughout temperate Eurasia, which shows a wide diversity of social and spatial organization. Within Britain, badgers are not only legally protected, but they also serve as a wildlife host for bovine tuberculosis Mycobacterium bovis. An evaluation of the role of badgers in the dynamics of this infection depends on understanding the responses of badgers to the environment at different spatial scales. 3The use of digital data to provide information on habitats for distribution models is becoming common. Digital data are increasingly accessible and are generally cheaper than field surveys. There has been little research, however, to compare the accuracy of models based on field-derived and remotely derived data. 4In this paper, we make quantified comparisons between large-scale presence/absence models for badgers in Britain, based on field-surveyed habitat data and remotely derived digital data, comprising elevation, geology and soil. 5We developed four models: 1980s badger survey data using field-based and digital data, and 1990s badger survey data using field-based and digital data. We divided each of the four datasets into two subsets and used one subset for training (developing) the model and the other for testing it. 6All four training models had classification accuracies in excess of 69%. The models generated from digital data were slightly more accurate than those generated from field-derived habitat data. 7The high classificatory ability of the digital-based models suggests that the use of digital data may overcome many of the problems associated with field data in wildlife-habitat modelling, such as cost and restricted geographical coverage, without any significant impact on model performance for some species. The more widespread use of digital data in wildlife-habitat models should enhance their accuracy, repeatability and applicability and make them better-suited as tools to aid policy- and decision-making processes. [source] Use of terrain variables for mapping gully erosion susceptibility in LebanonEARTH SURFACE PROCESSES AND LANDFORMS, Issue 12 2007Rania Bou Kheir Abstract This paper predicts the geographic distribution and size of gullies across central Lebanon using a geographic information system (GIS) and terrain analysis. Eleven primary (elevation; upslope contributing area; aspect; slope; plan, profile and tangential curvature; flow direction; flow width; flow path length; rate of change of specific catchment area along the direction of flow) and three secondary (steady-state; quasi-dynamic topographic wetness; sediment transport capacity) topographic variables were generated and used along with digital data collected from other sources (soil, geology) to statistically explain gully erosion field measurements. Three tree-based regression models were developed using (1) all variables, (2) primary topographic variables only and (3) different pairs of variables. The best regression tree model combined the steady-state topographic wetness and sediment transport capacity indices and explained 80% of the variability in field gully measurements. This model proved to be simple, quick, realistic and practical, and it can be applied to other areas of the Mediterranean region with similar environmental conditions, thereby providing a tool to help with the implementation of plans for soil conservation and sustainable management. Copyright © 2007 John Wiley & Sons, Ltd. [source] Digital Analysis of Myocardial Contrast Echocardiography: A Clinical Study Using an Air-Filled Agent in Normal SubjectsECHOCARDIOGRAPHY, Issue 3 2000EDWARD A. GEISER M.D., F.A.C.C. The purpose of the present study was to determine whether direct digital image analysis would allow improved detection of myocardial contrast. Eighteen normal subjects were recruited and separated into two groups. In group 1, the time-brightness curves of the left ventricular cavity and three myocardial perfusion beds were formed from digitized video tape, with output power and imaging time as secondary variables. In group 2, curves constructed from direct polar digital data were compared, with fundamental and second harmonic image formation as variables. In group 1 subjects, using fundamental imaging, the area under the curve in the left ventricular cavity increased slightly with intermittent imaging. No consistent myocardial opacification was identified. In group 2 subjects, using intermittent imaging, the area under the myocardial curve and peak intensity increased with high output second harmonic imaging in the left anterior descending and right coronary artery regions. Intermittent, second harmonic imaging and digital processing can demonstrate myocardial contrast even with an air-filled agent. [source] Full-duplex analogue/digital data transmission using lasers coupled to GI fibre and its applicationINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 5 2001Masayoshi Kamiya Abstract This paper describes a low-cost version of a full-duplex optical fibre analogue/digital data transmission link whose practical implementation is simplified by using a pair of laser diodes, each having a built-in photodiode for monitoring the laser output power, and its application to vibration test data transmission. The transmission link sends digital data of up to 9600 bps in one direction, and analogue data of DC to 100 kHz and image data specified by an NTSC colour video signal in the opposite direction, all at the same time through one GI optical fibre. Being simple in configuration and stable against noise, this type of link has a variety of applications within factory, home and offices. Copyright © 2001 John Wiley & Sons, Ltd. [source] DataNet: An emerging cyberinfrastructure for sharing, reusing and preserving digital data for scientific discovery and learningAICHE JOURNAL, Issue 11 2009Jae W. Lee First page of article [source] Quantification of red myotomal muscle volume and geometry in the shortfin mako shark (Isurus oxyrinchus) and the salmon shark (Lamna ditropis) using T1 -weighted magnetic resonance imagingJOURNAL OF MORPHOLOGY, Issue 4 2007Cameron N. Perry Abstract T1 -weighted magnetic resonance imaging (MRI) in conjunction with image and segmentation analysis (i.e., the process of digitally partitioning tissues based on specified MR image characteristics) was evaluated as a noninvasive alternative for differentiating muscle fiber types and quantifying the amounts of slow, red aerobic muscle in the shortfin mako shark (Isurus oxyrinchus) and the salmon shark (Lamna ditropis). MRI-determinations of red muscle quantity and position made for the mid-body sections of three mako sharks (73.5,110 cm fork length, FL) are in close agreement (within the 95% confidence intervals) with data obtained for the same sections by the conventional dissection method involving serial cross-sectioning and volumetric analyses, and with previously reported findings for this species. The overall distribution of salmon shark red muscle as a function of body fork length was also found to be consistent with previously acquired serial dissection data for this species; however, MR imaging revealed an anterior shift in peak red muscle cross-sectional area corresponding to an increase in body mass. Moreover, MRI facilitated visualization of the intact and anatomically correct relationship of tendon linking the red muscle and the caudal peduncle. This study thus demonstrates that MRI is effective in acquiring high-resolution three-dimensional digital data with high contrast between different fish tissue types. Relative to serial dissection, MRI allows more precise quantification of the position, volume, and other details about the types of muscle within the fish myotome, while conserving specimen structural integrity. J. Morphol., 2007. © 2007 Wiley-Liss, Inc. [source] COMPARISON OF HSPF OUTPUTS USING FTABLES GENERATED WITH FIELD SURVEY AND DIGITAL DATA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2006Nathan Staley ABSTRACT: The Hydrological Simulation Program-FORTRAN (HSPF) describes discharge from a stream reach based on function tables (FTABLES) that relate stream stage, surface area, volume, and discharge. For this study, five FTABLE scenarios were compared to assess their effect on daily discharge rates predicted using HSPF. Four "field-based" FTABLE scenarios were developed using detailed cross section surveys collected at predefined intervals along 14 reaches in the study watershed. A fifth "digital-based" scenario was developed using digital elevation models (DEMs) and Natural Resource Conservation Service (NRCS) Regional Hydraulic Geometry Curves. The Smirnov k-sample test was used to compare average daily discharge rates simulated with HSPF using the five FTABLE scenarios. No significant difference in simulated stream discharge was found (p = 0.99) between the five FTABLE scenarios. Additional examination of the four field-based scenarios revealed that the number of cross sections per stream reach used to generate FTABLES had little effect on the resulting stage discharge relationship. These findings suggest that FTABLES generated using digital data are a viable option when simulating stream discharge with HSPF and that if field data are used to generate FTABLES, using fewer cross sections will not adversely affect simulated discharge predictions. [source] Modelling the distribution of badgers Meles meles: comparing predictions from field-based and remotely derived habitat dataMAMMAL REVIEW, Issue 1 2007GERALDINE NEWTON-CROSS ABSTRACT 1Environmental heterogeneity is important in determining the distribution and abundance of organisms at various spatial scales. The ability to understand and predict distribution patterns is important for solving many management problems in conservation biology and wildlife epidemiology. 2The badger Meles meles is a highly adaptable, medium-sized carnivore, distributed throughout temperate Eurasia, which shows a wide diversity of social and spatial organization. Within Britain, badgers are not only legally protected, but they also serve as a wildlife host for bovine tuberculosis Mycobacterium bovis. An evaluation of the role of badgers in the dynamics of this infection depends on understanding the responses of badgers to the environment at different spatial scales. 3The use of digital data to provide information on habitats for distribution models is becoming common. Digital data are increasingly accessible and are generally cheaper than field surveys. There has been little research, however, to compare the accuracy of models based on field-derived and remotely derived data. 4In this paper, we make quantified comparisons between large-scale presence/absence models for badgers in Britain, based on field-surveyed habitat data and remotely derived digital data, comprising elevation, geology and soil. 5We developed four models: 1980s badger survey data using field-based and digital data, and 1990s badger survey data using field-based and digital data. We divided each of the four datasets into two subsets and used one subset for training (developing) the model and the other for testing it. 6All four training models had classification accuracies in excess of 69%. The models generated from digital data were slightly more accurate than those generated from field-derived habitat data. 7The high classificatory ability of the digital-based models suggests that the use of digital data may overcome many of the problems associated with field data in wildlife-habitat modelling, such as cost and restricted geographical coverage, without any significant impact on model performance for some species. The more widespread use of digital data in wildlife-habitat models should enhance their accuracy, repeatability and applicability and make them better-suited as tools to aid policy- and decision-making processes. [source] A new high-resolution computed tomography (CT) segmentation method for trabecular bone architectural analysisAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2009Heike Scherf Abstract In the last decade, high-resolution computed tomography (CT) and microcomputed tomography (micro-CT) have been increasingly used in anthropological studies and as a complement to traditional histological techniques. This is due in large part to the ability of CT techniques to nondestructively extract three-dimensional representations of bone structures. Despite prior studies employing CT techniques, no completely reliable method of bone segmentation has been established. Accurate preprocessing of digital data is crucial for measurement accuracy, especially when subtle structures such as trabecular bone are investigated. The research presented here is a new, reproducible, accurate, and fully automated computerized segmentation method for high-resolution CT datasets of fossil and recent cancellous bone: the Ray Casting Algorithm (RCA). We compare this technique with commonly used methods of image thresholding (i.e., the half-maximum height protocol and the automatic, adaptive iterative thresholding procedure). While the quality of the input images is crucial for conventional image segmentation, the RCA method is robust regarding the signal to noise ratio, beam hardening, ring artifacts, and blurriness. Tests with data of extant and fossil material demonstrate the superior quality of RCA compared with conventional thresholding procedures, and emphasize the need for careful consideration of optimal CT scanning parameters. Am J Phys Anthropol 2009. © 2009 Wiley-Liss, Inc. [source] Robotic Membranes: Exploring a Textile Architecture of BehaviourARCHITECTURAL DESIGN, Issue 4 2008Mette Ramsgard Thomsen Abstract The robot and the textile seem like a contradiction in terms - the robot standing for everything that is automated and mechanical, and the textile for sensual materiality. Can it be possible to reconcile the two? Here Mette Ramsgard Thomsen demonstrates through her Vivisections and Strange Metabolisms projects, exhibited at the Centre for Information, Technology and Architecture (CITA) in Copenhagen, how it is possible to unite the seeming polarities of the digital and the physical, engaging,intangible digital data with tactile physical material'. Copyright © 2008 John Wiley & Sons, Ltd. [source] A procedure for setting up high-throughput nanolitre crystallization experiments.ACTA CRYSTALLOGRAPHICA SECTION D, Issue 6 2005Crystallization workflow for initial screening, automated storage, imaging, optimization Crystallization trials at the Division of Structural Biology in Oxford are now almost exclusively carried out using a high-throughput workflow implemented in the Oxford Protein Production Facility. Initial crystallization screening is based on nanolitre-scale sitting-drop vapour-diffusion experiments (typically 100,nl of protein plus 100,nl of reservoir solution per droplet) which use standard crystallization screening kits and 96-well crystallization plates. For 294,K crystallization trials the barcoded crystallization plates are entered into an automated storage system with a fully integrated imaging system. These plates are imaged in accordance with a pre-programmed schedule and the resulting digital data for each droplet are harvested into a laboratory information-management system (LIMS), scored by crystal recognition software and displayed for user analysis via a web-based interface. Currently, storage for trials at 277,K is not automated and for imaging the crystallization plates are fed by hand into an imaging system from which the data enter the LIMS. The workflow includes two procedures for nanolitre-scale optimization of crystallization conditions: (i) a protocol for variation of pH, reservoir dilution and protein:reservoir ratio and (ii) an additive screen. Experience based on 592 crystallization projects is reported. [source] | ||||||||||||||||