100+ datasets found
  1. n

    Data from: Evaluating range-expansion models for calculating nonnative...

    • data.niaid.nih.gov
    • datadryad.org
    zip
    Updated Apr 28, 2015
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    Sonja Preuss; Matthew Low; Anna Cassel-Lundhagen; Åsa Berggren (2015). Evaluating range-expansion models for calculating nonnative species’ expansion rate [Dataset]. http://doi.org/10.5061/dryad.ns624
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    zipAvailable download formats
    Dataset updated
    Apr 28, 2015
    Dataset provided by
    Swedish University of Agricultural Sciences
    Authors
    Sonja Preuss; Matthew Low; Anna Cassel-Lundhagen; Åsa Berggren
    License

    https://spdx.org/licenses/CC0-1.0.htmlhttps://spdx.org/licenses/CC0-1.0.html

    Area covered
    Sweden
    Description
    1. Species range shifts associated with environmental change or biological invasions are increasingly important study areas. However, quantifying range expansion rates may be heavily influenced by methodology and/or sampling bias. 2. We compared expansion rate estimates of Roesel’s bush-cricket (Metrioptera roeselii, Hagenbach 1822), a non-native species currently expanding its range in south-central Sweden, from range statistic models based on distance measures (mean, median, 95th gamma quantile, marginal mean, maximum and conditional maximum) and an area-based method (grid occupancy). We used sampling simulations to determine the sensitivity of the different methods to incomplete sampling across the species’ range. 3. For periods when we had comprehensive survey data, range expansion estimates clustered into two groups: (i) those calculated from range margin statistics (gamma, marginal mean, maximum and conditional maximum: ~3 km/yr), and (ii) those calculated from the central tendency (mean and median) and the area-based method of grid occupancy (~1.5 km/yr). 4. Range statistic measures differed greatly in their sensitivity to sampling effort; the proportion of sampling required to achieve an estimate within 10% of the true value ranged from 0.17-0.9. Grid occupancy and median were most sensitive to sampling effort, and the maximum and gamma quantile the least. 5. If periods with incomplete sampling were included in the range expansion calculations, this generally lowered the estimates (range 16-72%), with exception of the gamma quantile that was slightly higher (6%). 6. Care should be taken when interpreting rate expansion estimates from data sampled from only a fraction of the full distribution. Methods based on the central tendency will give rates approximately half that of methods based on the range margin. The gamma quantile method appears to be the most robust to incomplete sampling bias and should be considered as the method of choice when sampling the entire distribution is not possible.
  2. R

    Distance Calculation Dataset

    • universe.roboflow.com
    zip
    Updated Mar 2, 2023
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    jatin-rane (2023). Distance Calculation Dataset [Dataset]. https://universe.roboflow.com/jatin-rane/distance-calculation/model/3
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    zipAvailable download formats
    Dataset updated
    Mar 2, 2023
    Dataset authored and provided by
    jatin-rane
    License

    CC0 1.0 Universal Public Domain Dedicationhttps://creativecommons.org/publicdomain/zero/1.0/
    License information was derived automatically

    Variables measured
    Vehicles Bounding Boxes
    Description

    Distance Calculation

    ## Overview
    
    Distance Calculation is a dataset for object detection tasks - it contains Vehicles annotations for 4,056 images.
    
    ## Getting Started
    
    You can download this dataset for use within your own projects, or fork it into a workspace on Roboflow to create your own model.
    
      ## License
    
      This dataset is available under the [Public Domain license](https://creativecommons.org/licenses/Public Domain).
    
  3. Braking Distance data

    • kaggle.com
    Updated Jun 11, 2024
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    Ritu Parna Ghosh (2024). Braking Distance data [Dataset]. https://www.kaggle.com/datasets/rituparnaghosh18/braking-distance-data
    Explore at:
    CroissantCroissant is a format for machine-learning datasets. Learn more about this at mlcommons.org/croissant.
    Dataset updated
    Jun 11, 2024
    Dataset provided by
    Kaggle
    Authors
    Ritu Parna Ghosh
    License

    https://creativecommons.org/publicdomain/zero/1.0/https://creativecommons.org/publicdomain/zero/1.0/

    Description

    This mini dataset is having 2 columns for calculating the braking distance of a car i.e., the distance a vehicle will travel from the point when its brakes are fully applied to when it comes to a complete stop.

  4. d

    Data from: U.S. Geological Survey calculated half interpercentile range...

    • catalog.data.gov
    • search.dataone.org
    • +1more
    Updated Nov 26, 2025
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    U.S. Geological Survey (2025). U.S. Geological Survey calculated half interpercentile range (half of the difference between the 16th and 84th percentiles) of wave-current bottom shear stress in the South Atlantic Bight from May 2010 to May 2011 (SAB_hIPR.shp, polygon shapefile, Geographic, WGS84) [Dataset]. https://catalog.data.gov/dataset/u-s-geological-survey-calculated-half-interpercentile-range-half-of-the-difference-between
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    Dataset updated
    Nov 26, 2025
    Dataset provided by
    United States Geological Surveyhttp://www.usgs.gov/
    Description

    The U.S. Geological Survey has been characterizing the regional variation in shear stress on the sea floor and sediment mobility through statistical descriptors. The purpose of this project is to identify patterns in stress in order to inform habitat delineation or decisions for anthropogenic use of the continental shelf. The statistical characterization spans the continental shelf from the coast to approximately 120 m water depth, at approximately 5 km resolution. Time-series of wave and circulation are created using numerical models, and near-bottom output of steady and oscillatory velocities and an estimate of bottom roughness are used to calculate a time-series of bottom shear stress at 1-hour intervals. Statistical descriptions such as the median and 95th percentile, which are the output included with this database, are then calculated to create a two-dimensional picture of the regional patterns in shear stress. In addition, time-series of stress are compared to critical stress values at select points calculated from observed surface sediment texture data to determine estimates of sea floor mobility.

  5. R

    Golf Ball Distance Calculation Dataset

    • universe.roboflow.com
    zip
    Updated Jun 14, 2025
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    Awais Ahmad (2025). Golf Ball Distance Calculation Dataset [Dataset]. https://universe.roboflow.com/awais-ahmad-dtpcl/golf-ball-distance-calculation/dataset/1
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    zipAvailable download formats
    Dataset updated
    Jun 14, 2025
    Dataset authored and provided by
    Awais Ahmad
    License

    Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
    License information was derived automatically

    Variables measured
    Golf Balls Bounding Boxes
    Description

    Golf Ball Distance Calculation

    ## Overview
    
    Golf Ball Distance Calculation is a dataset for object detection tasks - it contains Golf Balls annotations for 318 images.
    
    ## Getting Started
    
    You can download this dataset for use within your own projects, or fork it into a workspace on Roboflow to create your own model.
    
      ## License
    
      This dataset is available under the [CC BY 4.0 license](https://creativecommons.org/licenses/CC BY 4.0).
    
  6. m

    Dataset for The effects of a number line intervention on calculation skills

    • figshare.mq.edu.au
    • researchdata.edu.au
    txt
    Updated May 12, 2023
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    Carola Ruiz Hornblas; Saskia Kohnen; Rebecca Bull (2023). Dataset for The effects of a number line intervention on calculation skills [Dataset]. http://doi.org/10.25949/22799717.v1
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    txtAvailable download formats
    Dataset updated
    May 12, 2023
    Dataset provided by
    Macquarie University
    Authors
    Carola Ruiz Hornblas; Saskia Kohnen; Rebecca Bull
    License

    Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
    License information was derived automatically

    Description

    Study information The sample included in this dataset represents five children who participated in a number line intervention study. Originally six children were included in the study, but one of them fulfilled the criterion for exclusion after missing several consecutive sessions. Thus, their data is not included in the dataset. All participants were currently attending Year 1 of primary school at an independent school in New South Wales, Australia. For children to be able to eligible to participate they had to present with low mathematics achievement by performing at or below the 25th percentile in the Maths Problem Solving and/or Numerical Operations subtests from the Wechsler Individual Achievement Test III (WIAT III A & NZ, Wechsler, 2016). Participants were excluded from participating if, as reported by their parents, they have any other diagnosed disorders such as attention deficit hyperactivity disorder, autism spectrum disorder, intellectual disability, developmental language disorder, cerebral palsy or uncorrected sensory disorders. The study followed a multiple baseline case series design, with a baseline phase, a treatment phase, and a post-treatment phase. The baseline phase varied between two and three measurement points, the treatment phase varied between four and seven measurement points, and all participants had 1 post-treatment measurement point. The number of measurement points were distributed across participants as follows: Participant 1 – 3 baseline, 6 treatment, 1 post-treatment Participant 3 – 2 baseline, 7 treatment, 1 post-treatment Participant 5 – 2 baseline, 5 treatment, 1 post-treatment Participant 6 – 3 baseline, 4 treatment, 1 post-treatment Participant 7 – 2 baseline, 5 treatment, 1 post-treatment In each session across all three phases children were assessed in their performance on a number line estimation task, a single-digit computation task, a multi-digit computation task, a dot comparison task and a number comparison task. Furthermore, during the treatment phase, all children completed the intervention task after these assessments. The order of the assessment tasks varied randomly between sessions.

    Measures Number Line Estimation. Children completed a computerised bounded number line task (0-100). The number line is presented in the middle of the screen, and the target number is presented above the start point of the number line to avoid signalling the midpoint (Dackermann et al., 2018). Target numbers included two non-overlapping sets (trained and untrained) of 30 items each. Untrained items were assessed on all phases of the study. Trained items were assessed independent of the intervention during baseline and post-treatment phases, and performance on the intervention is used to index performance on the trained set during the treatment phase. Within each set, numbers were equally distributed throughout the number range, with three items within each ten (0-10, 11-20, 21-30, etc.). Target numbers were presented in random order. Participants did not receive performance-based feedback. Accuracy is indexed by percent absolute error (PAE) [(number estimated - target number)/ scale of number line] x100.

    Single-Digit Computation. The task included ten additions with single-digit addends (1-9) and single-digit results (2-9). The order was counterbalanced so that half of the additions present the lowest addend first (e.g., 3 + 5) and half of the additions present the highest addend first (e.g., 6 + 3). This task also included ten subtractions with single-digit minuends (3-9), subtrahends (1-6) and differences (1-6). The items were presented horizontally on the screen accompanied by a sound and participants were required to give a verbal response. Participants did not receive performance-based feedback. Performance on this task was indexed by item-based accuracy.

    Multi-digit computational estimation. The task included eight additions and eight subtractions presented with double-digit numbers and three response options. None of the response options represent the correct result. Participants were asked to select the option that was closest to the correct result. In half of the items the calculation involved two double-digit numbers, and in the other half one double and one single digit number. The distance between the correct response option and the exact result of the calculation was two for half of the trials and three for the other half. The calculation was presented vertically on the screen with the three options shown below. The calculations remained on the screen until participants responded by clicking on one of the options on the screen. Participants did not receive performance-based feedback. Performance on this task is measured by item-based accuracy.

    Dot Comparison and Number Comparison. Both tasks included the same 20 items, which were presented twice, counterbalancing left and right presentation. Magnitudes to be compared were between 5 and 99, with four items for each of the following ratios: .91, .83, .77, .71, .67. Both quantities were presented horizontally side by side, and participants were instructed to press one of two keys (F or J), as quickly as possible, to indicate the largest one. Items were presented in random order and participants did not receive performance-based feedback. In the non-symbolic comparison task (dot comparison) the two sets of dots remained on the screen for a maximum of two seconds (to prevent counting). Overall area and convex hull for both sets of dots is kept constant following Guillaume et al. (2020). In the symbolic comparison task (Arabic numbers), the numbers remained on the screen until a response was given. Performance on both tasks was indexed by accuracy.

    The Number Line Intervention During the intervention sessions, participants estimated the position of 30 Arabic numbers in a 0-100 bounded number line. As a form of feedback, within each item, the participants’ estimate remained visible, and the correct position of the target number appeared on the number line. When the estimate’s PAE was lower than 2.5, a message appeared on the screen that read “Excellent job”, when PAE was between 2.5 and 5 the message read “Well done, so close! and when PAE was higher than 5 the message read “Good try!” Numbers were presented in random order.

    Variables in the dataset Age = age in ‘years, months’ at the start of the study Sex = female/male/non-binary or third gender/prefer not to say (as reported by parents) Math_Problem_Solving_raw = Raw score on the Math Problem Solving subtest from the WIAT III (WIAT III A & NZ, Wechsler, 2016). Math_Problem_Solving_Percentile = Percentile equivalent on the Math Problem Solving subtest from the WIAT III (WIAT III A & NZ, Wechsler, 2016). Num_Ops_Raw = Raw score on the Numerical Operations subtest from the WIAT III (WIAT III A & NZ, Wechsler, 2016). Math_Problem_Solving_Percentile = Percentile equivalent on the Numerical Operations subtest from the WIAT III (WIAT III A & NZ, Wechsler, 2016).

    The remaining variables refer to participants’ performance on the study tasks. Each variable name is composed by three sections. The first one refers to the phase and session. For example, Base1 refers to the first measurement point of the baseline phase, Treat1 to the first measurement point on the treatment phase, and post1 to the first measurement point on the post-treatment phase.

    The second part of the variable name refers to the task, as follows: DC = dot comparison SDC = single-digit computation NLE_UT = number line estimation (untrained set) NLE_T= number line estimation (trained set) CE = multidigit computational estimation NC = number comparison The final part of the variable name refers to the type of measure being used (i.e., acc = total correct responses and pae = percent absolute error).

    Thus, variable Base2_NC_acc corresponds to accuracy on the number comparison task during the second measurement point of the baseline phase and Treat3_NLE_UT_pae refers to the percent absolute error on the untrained set of the number line task during the third session of the Treatment phase.

  7. d

    Data from: Exact finite range DWBA calculations for heavy-ion induced...

    • elsevier.digitalcommonsdata.com
    Updated Jan 1, 1974
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    T. Tamura (1974). Exact finite range DWBA calculations for heavy-ion induced nuclear reactions [Dataset]. http://doi.org/10.17632/xthy9b534c.1
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    Dataset updated
    Jan 1, 1974
    Authors
    T. Tamura
    License

    https://www.elsevier.com/about/policies/open-access-licenses/elsevier-user-license/cpc-license/https://www.elsevier.com/about/policies/open-access-licenses/elsevier-user-license/cpc-license/

    Description

    Title of program: MARS-1-FOR-EFR-DWBA Catalogue Id: ABPB_v1_0

    Nature of problem The package SATURN-MARS-1 consists of two programs SATURN and MARS for calculating cross sections of reactions transferring nucleon(s) primarily between two heavy ions. The calculations are made within the framework of the finite-range distorted wave Born approximation(DWBA). The first part, SATURN, prepares the form factor(s) either for exact finite (EFR) or for no-recoil (NR) approach. The prepared form factor is then used by the second part MARS to calculate either EFR-DWBA or NR-DWBA cross-s ...

    Versions of this program held in the CPC repository in Mendeley Data abpb_v1_0; MARS-1-FOR-EFR-DWBA; 10.1016/0010-4655(74)90012-5

    This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)

  8. S

    Data from: A wide-range multiphase equation of state for lead

    • scidb.cn
    Updated Jun 23, 2025
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    Fang Jun; zhao yan hong; Gao Xingyu; Zhang Qili; Wang Yuechao; Sun Bo; Liu Haifeng; Song Haifeng (2025). A wide-range multiphase equation of state for lead [Dataset]. http://doi.org/10.57760/sciencedb.j00213.00166
    Explore at:
    CroissantCroissant is a format for machine-learning datasets. Learn more about this at mlcommons.org/croissant.
    Dataset updated
    Jun 23, 2025
    Dataset provided by
    Science Data Bank
    Authors
    Fang Jun; zhao yan hong; Gao Xingyu; Zhang Qili; Wang Yuechao; Sun Bo; Liu Haifeng; Song Haifeng
    Description

    This dataset provides the equation of state data for lead in the temperature and pressure range from room temperature to 10 MK, and from atmospheric pressure to 107GPa. The thermodynamic properties of the shock Hugoniot line, 300 K isotherm, melting line, and temperature dense transition zone were calculated.

  9. d

    Data from: Home range and movement metric data of resident and translocated...

    • catalog.data.gov
    • data.usgs.gov
    • +1more
    Updated Oct 2, 2025
    + more versions
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    U.S. Geological Survey (2025). Home range and movement metric data of resident and translocated Giant gartersnakes (Thamnophis gigas) in Sacramento, CA, USA, in 2018 to 2021 [Dataset]. https://catalog.data.gov/dataset/home-range-and-movement-metric-data-of-resident-and-translocated-giant-gartersnakes-thamno
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    Dataset updated
    Oct 2, 2025
    Dataset provided by
    U.S. Geological Survey
    Area covered
    California, Sacramento, United States
    Description

    The dataset consists of two csv files one for home range and net displacement analysis for adult snakes with at least 20 locations collected during the study period and one for the analysis of movement metrics for all adult snakes in the study. The home range data contains the calculated 100 percent and 95 percent minimum convex polygons (MCP) and 95 percent adaptive local convex hull (a-LoCoH) home range estimates, 3 measures of net displacement from the release location of the snake as well as other pertinent information about individual snakes (year included in study, id, treatment group, site, snout to vent length (SVL)). The movement data contains calculations of the following movement metrics: sinuosity, start-to-end distance, and total distance traversed of seasonal movement paths as well as information about individual snakes described above.

  10. Traveling Salesman Computer Vision

    • kaggle.com
    zip
    Updated Apr 20, 2022
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    Jeff Heaton (2022). Traveling Salesman Computer Vision [Dataset]. https://www.kaggle.com/datasets/jeffheaton/traveling-salesman-computer-vision
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    zip(2977884049 bytes)Available download formats
    Dataset updated
    Apr 20, 2022
    Authors
    Jeff Heaton
    License

    http://www.gnu.org/licenses/lgpl-3.0.htmlhttp://www.gnu.org/licenses/lgpl-3.0.html

    Description

    The Traveling Salesperson Problem (TSP) is a class problem of computer science that seeks to find the shortest route between a group of cities. It is an NP-hard problem in combinatorial optimization, important in theoretical computer science and operations research.

    https://data.heatonresearch.com/images/wustl/kaggle/tsp/world-tsp.png" alt="World Map">

    In this Kaggle competition, your goal is not to find the shortest route among cities. Rather, you must attempt to determine the route labeled on a map.

    Calculating Line Distances

    The data for this competition is not made up of real-world maps, but rather randomly generated maps of varying attributes of size, city count, and optimality of the routes. The following image demonstrates a relatively small map, with few cities, and an optimal route.

    https://data.heatonresearch.com/images/wustl/kaggle/tsp/1.jpg" alt="Small Map">

    Not all maps are this small, or contain this optimal a route. Consider the following map, which is much larger.

    https://data.heatonresearch.com/images/wustl/kaggle/tsp/6.jpg" alt="Larger Map">

    The following attributes were randomly selected to generate each image.

    • Height
    • Width
    • City count
    • Cycles of Simulated Annealing optimization of initial random path

    The path distance is based on the sum of the Euclidean distance of all segments in the path. The distance units are in pixels.

    Dataset Challenges

    This is a regression problem, you are to estimate the total path length. Several challenges to consider.

    • If you indiscriminately scale the maps, you will lose size information.
    • Paths might overlap, causing the ration of total pixels to total length to become misleading.
    • As paths overlap bot other path segments and cities, the resulting color becomes brighter.

    The following picture shows a section from one map zoomed to the pixel-level:

    https://data.heatonresearch.com/images/wustl/kaggle/tsp/tsp_zoom.jpg" alt="TSP Zoom">

    CSV Files

    The following CSV files are provided, in addition to the images.

    • train.csv - Training data, with distance labels.
    • test.csv - Test data without distance labels.
    • tsp-all.csv - Training and test data combined with complete labels and additional information about each generated map.

    CSV File Format

    The tsp-all.csv file contains the following data.

    id,filename,distance,key
    0,0.jpg,83110,503x673-270-83110.jpg
    1,1.jpg,1035,906x222-10-1035.jpg
    2,2.jpg,20756,810x999-299-20756.jpg
    3,3.jpg,13286,781x717-272-13286.jpg
    4,4.jpg,13924,609x884-312-13924.jpg
    

    The columns:

    • id - A unique ID that allows linking across all three CSV files.
    • filename - The name of each map's image file.
    • distance - The total distance through the cities, this is the y/label.
    • key - The generator filename, provides the dimensions, city count, & distance.
  11. d

    Distance to the nearest stream by stream order for eighteen selected...

    • catalog.data.gov
    • data.usgs.gov
    Updated Nov 27, 2025
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    U.S. Geological Survey (2025). Distance to the nearest stream by stream order for eighteen selected watersheds in the United States, Comma-separated value formatted [Dataset]. https://catalog.data.gov/dataset/distance-to-the-nearest-stream-by-stream-order-for-eighteen-selected-watersheds-in-the-uni
    Explore at:
    Dataset updated
    Nov 27, 2025
    Dataset provided by
    United States Geological Surveyhttp://www.usgs.gov/
    Area covered
    United States
    Description

    Accurate representation of stream networks at various scales in a hydrogeologic system is integral to modeling groundwater-stream interactions at the continental scale. To assess the accurate representation of stream networks, the distance of a point on the land surface to the nearest stream (DS) has been calculated. DS was calculated from the 30-meter Multi Order Hydrologic Position (MOHP) raster datasets for 18 watersheds in the United States that have been prioritized for intensive monitoring and assessment by the U.S. Geological Survey. DS was calculated by multiplying the 30-meter MOHP Lateral Position (LP) datasets by the 30-meter MOHP Distance from Stream Divide (DSD) datasets for stream orders one through five. DS was calculated for the purposes of considering the spatial scale needed for accurate representation of groundwater-stream interaction at the continental scale for a grid with 1-kilometer cell spacing. The data are available as Comma-Separated Value formatted files.

  12. f

    Summary and methods used to calculate the physical characteristics used to...

    • datasetcatalog.nlm.nih.gov
    • plos.figshare.com
    Updated Mar 31, 2017
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    Nathan, Senthilvel K. S. S.; Saldivar, Diana A. Ramirez; Vaughan, Ian P.; Goossens, Benoit; Stark, Danica J. (2017). Summary and methods used to calculate the physical characteristics used to compare the home range estimators. [Dataset]. https://datasetcatalog.nlm.nih.gov/dataset?q=0001743878
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    Dataset updated
    Mar 31, 2017
    Authors
    Nathan, Senthilvel K. S. S.; Saldivar, Diana A. Ramirez; Vaughan, Ian P.; Goossens, Benoit; Stark, Danica J.
    Description

    Summary and methods used to calculate the physical characteristics used to compare the home range estimators.

  13. f

    Data from: Numerical Simulation Strategy and Applications for Falling Film...

    • acs.figshare.com
    xlsx
    Updated Jan 3, 2025
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    Wenxu Yuan; Wenxing Chen; Shichang Chen (2025). Numerical Simulation Strategy and Applications for Falling Film Flow with Variable Viscosity Fluids [Dataset]. http://doi.org/10.1021/acs.iecr.4c03582.s001
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    xlsxAvailable download formats
    Dataset updated
    Jan 3, 2025
    Dataset provided by
    ACS Publications
    Authors
    Wenxu Yuan; Wenxing Chen; Shichang Chen
    License

    Attribution-NonCommercial 4.0 (CC BY-NC 4.0)https://creativecommons.org/licenses/by-nc/4.0/
    License information was derived automatically

    Description

    The flow behaviors for falling film with wide-range variable viscosity were demonstrated by a neosimulation strategy, which incorporated the age transport equation based on mean age theory and a designable age-viscosity formula into Navier–Stokes equations. Surprisingly, a turning region was revealed, in which the thickness variation for variable viscosity falling film with the flow rate and initial viscosity was reversed. The larger the flow rate or the higher the initial viscosity, the longer the length of the turning region, and further, it was from the inlet along the flow direction. A flow cross-sectional viscosity was proposed to explain this anomaly. Then, a simulation scheme for calculating the initial viscosity based on outlet viscosity and an empirical equation for designing the length of the falling film pipe could be achieved according to flow cross-sectional viscosity analysis. It provided a practical reference for falling film reactor design, scale-up, and process optimization.

  14. GLAS/ICESat L1B Global Waveform-based Range Corrections Data (HDF5) V034 -...

    • data.nasa.gov
    Updated Mar 31, 2025
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    nasa.gov (2025). GLAS/ICESat L1B Global Waveform-based Range Corrections Data (HDF5) V034 - Dataset - NASA Open Data Portal [Dataset]. https://data.nasa.gov/dataset/glas-icesat-l1b-global-waveform-based-range-corrections-data-hdf5-v034
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    Dataset updated
    Mar 31, 2025
    Dataset provided by
    NASAhttp://nasa.gov/
    Description

    GLAH05 Level-1B waveform parameterization data include output parameters from the waveform characterization procedure and other parameters required to calculate surface slope and relief characteristics. GLAH05 contains parameterizations of both the transmitted and received pulses and other characteristics from which elevation and footprint-scale roughness and slope are calculated. The received pulse characterization uses two implementations of the retracking algorithms: one tuned for ice sheets, called the standard parameterization, used to calculate surface elevation for ice sheets, oceans, and sea ice; and another for land (the alternative parameterization). Each data granule has an associated browse product.

  15. z

    mmWave-based Fitness Activity Recognition Dataset

    • zenodo.org
    png, zip
    Updated Jul 12, 2024
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    Yucheng Xie; Xiaonan Guo; Yan Wang; Jerry Cheng; Yingying Chen; Yucheng Xie; Xiaonan Guo; Yan Wang; Jerry Cheng; Yingying Chen (2024). mmWave-based Fitness Activity Recognition Dataset [Dataset]. http://doi.org/10.5281/zenodo.7793613
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    zip, pngAvailable download formats
    Dataset updated
    Jul 12, 2024
    Dataset provided by
    Zenodo
    Authors
    Yucheng Xie; Xiaonan Guo; Yan Wang; Jerry Cheng; Yingying Chen; Yucheng Xie; Xiaonan Guo; Yan Wang; Jerry Cheng; Yingying Chen
    License

    Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
    License information was derived automatically

    Description

    Description:

    This mmWave Datasets are used for fitness activity identification. This dataset (FA Dataset) contains 14 common fitness daily activities. The data are captured by the mmWave radar TI-AWR1642. The dataset can be used by fellow researchers to reproduce the original work or to further explore other machine-learning problems in the domain of mmWave signals.

    Format: .png format

    Section 1: Device Configuration

    Section 2: Data Format

    We provide our mmWave data in heatmaps for this dataset. The data file is in the png format. The details are shown in the following:

    • 14 activities are included in the FA Dataset.
    • 2 participants are included in the FA Dataset.
    • FA_d_p_i_u_j.png:
      • d represents the date to collect the fitness data.
      • p represents the environment to collect the fitness data.
      • i represents fitness activity type index
      • u represents user id
      • j represents sample index
    • Example:
      • FA_20220101_lab_1_2_3 represents the 3rd data sample of user 2 of activity 1 collected in the lab

    Section 3: Experimental Setup

    • We place the mmWave device on a table with a height of 60cm.
    • The participants are asked to perform fitness activity in front of a mmWave device with a distance of 2m.
    • The data are collected at an lab with a size of (5.0m×3.0m).

    Section 4: Data Description

    • We develop a spatial-temporal heatmap to integrates multiple activity features, including the range of movement, velocity, and time duration of each activity repetition.

    • We first derive the Doppler-range map of the users' activity by calculating Range-FFT and Doppler-FFT. Then, we generate the spatial-temporal heatmap by accumulating the velocity of every distance in every Doppler-range map together. Next, we normalize the derived velocity information and present the velocity-distance relationship in time dimension. In this way, we transfer the original instantaneous velocity-distance relationship to a more comprehensive spatial-temporal heatmap which describes the process of a whole activity.

    • As shown in Figure attached, in each spatial-temporal heatmap, the horizontal axis represents the time duration of an activity repetition while the vertical axis represents the range of movement. The velocity is represented by color.

    • We create 14 zip files to store the the dataset. There are 14 zip files starting with "FA", each contains repetitions from the same fitness activity.

    14 common daily activities and their corresponding files

    File Name Activity Type File Name Activity Type

    FA1 Crunches FA8 Squats

    FA2 Elbow plank and reach FA9 Burpees

    FA3 Leg raise FA10 Chest squeezes

    FA4 Lunges FA11 High knees

    FA5 Mountain climber FA12 Side leg raise

    FA6 Punches FA13 Side to side chops

    FA7 Push ups FA14 Turning kicks

    Section 5: Raw Data and Data Processing Algorithms

    • We also provide the mmWave raw data (.mat format) stored in the same zip file corresponding to the heatmap datasets. Each .mat file can store one set of activity repetitions (e.g., 4 repetations) from a same user.
      • For example: FA_d_p_i_u_j.mat:
        • d represents the data to collect the data.
        • p represents the environment to collect the data.
        • i represents the activity type index
        • u represents the user id
        • j represents the set index
    • We plan to provide the data processing algorithms (heatmap_generation.py) to load the mmWave raw data and generate the corresponding heatmap data.

    Section 6: Citations

    If your paper is related to our works, please cite our papers as follows.

    https://ieeexplore.ieee.org/document/9868878/

    Xie, Yucheng, Ruizhe Jiang, Xiaonan Guo, Yan Wang, Jerry Cheng, and Yingying Chen. "mmFit: Low-Effort Personalized Fitness Monitoring Using Millimeter Wave." In 2022 International Conference on Computer Communications and Networks (ICCCN), pp. 1-10. IEEE, 2022.

    Bibtex:

    @inproceedings{xie2022mmfit,

    title={mmFit: Low-Effort Personalized Fitness Monitoring Using Millimeter Wave},

    author={Xie, Yucheng and Jiang, Ruizhe and Guo, Xiaonan and Wang, Yan and Cheng, Jerry and Chen, Yingying},

    booktitle={2022 International Conference on Computer Communications and Networks (ICCCN)},

    pages={1--10},

    year={2022},

    organization={IEEE}

    }

  16. Helsinki Region Travel Time Matrix

    • zenodo.org
    • data.niaid.nih.gov
    zip
    Updated Jan 24, 2020
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    Henrikki Tenkanen; Henrikki Tenkanen; Tuuli Toivonen; Tuuli Toivonen (2020). Helsinki Region Travel Time Matrix [Dataset]. http://doi.org/10.5281/zenodo.3247564
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    zipAvailable download formats
    Dataset updated
    Jan 24, 2020
    Dataset provided by
    Zenodohttp://zenodo.org/
    Authors
    Henrikki Tenkanen; Henrikki Tenkanen; Tuuli Toivonen; Tuuli Toivonen
    License

    Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
    License information was derived automatically

    Area covered
    Helsinki metropolitan area, Helsinki
    Description

    Helsinki Region Travel Time Matrix contains travel time and distance information for routes between all 250 m x 250 m grid cell centroids (n = 13231) in the Helsinki Region, Finland by walking, cycling, public transportation and car. The grid cells are compatible with the statistical grid cells used by Statistics Finland and the YKR (yhdyskuntarakenteen seurantajärjestelmä) data set. The Helsinki Region Travel Time Matrix is available for three different years:

    • 2018
    • 2015
    • 2013

    The data consists of travel time and distance information of the routes that have been calculated between all statistical grid cell centroids (n = 13231) by walking, cycling, public transportation and car.

    The data have been calculated for two different times of the day: 1) midday and 2) rush hour.

    The data may be used freely (under Creative Commons 4.0 licence). We do not take any responsibility for any mistakes, errors or other deficiencies in the data.

    Organization of data

    The data have been divided into 13231 text files according to destinations of the routes. The data files have been organized into sub-folders that contain multiple (approx. 4-150) Travel Time Matrix result files. Individual folders consist of all the Travel Time Matrices that have same first four digits in their filename (e.g. 5785xxx).

    In order to visualize the data on a map, the result tables can be joined with the MetropAccess YKR-grid shapefile (attached here). The data can be joined by using the field ‘from_id’ in the text files and the field ‘YKR_ID’ in MetropAccess-YKR-grid shapefile as a common key.

    Data structure

    The data have been divided into 13231 text files according to destinations of the routes. One file includes the routes from all statistical grid cells to a particular destination grid cell. All files have been named according to the destination grid cell code and each file includes 13231 rows.

    NODATA values have been stored as value -1.

    Each file consists of 17 attribute fields: 1) from_id, 2) to_id, 3) walk_t, 4) walk_d, 5) bike_f_t, 6) bike_s_t, 7) bike_d, 8) pt_r_tt, 9) pt_r_t, 10) pt_r_d, 11) pt_m_tt, 12) pt_m_t, 13) pt_m_d, 14) car_r_t, 15) car_r_d, 16) car_m_t, 17) car_m_d, 18) car_sl_t

    The fields are separated by semicolon in the text files.

    Attributes

    • from_id: ID number of the origin grid cell
    • to_id: ID number of the destination grid cell
    • walk_t: Travel time in minutes from origin to destination by walking
    • walk_d: Distance in meters of the walking route
    • bike_f_t: Total travel time in minutes from origin to destination by fast cycling; Includes extra time (1 min) that it takes to take/return bike
    • bike_s_t: Total travel time in minutes from origin to destination by slow cycling; Includes extra time (1 min) that it takes to take/return bike
    • bike_d:Distance in meters of the cycling route
    • pt_r_tt: Travel time in minutes from origin to destination by public transportation in rush hour traffic; whole travel chain has been taken into account including the waiting time at home
    • pt_r_t: Travel time in minutes from origin to destination by public transportation in rush hour traffic; whole travel chain has been taken into account excluding the waiting time at home
    • pt_r_d: Distance in meters of the public transportation route in rush hour traffic
    • pt_m_tt: Travel time in minutes from origin to destination by public transportation in midday traffic; whole travel chain has been taken into account including the waiting time at home
    • pt_m_t: Travel time in minutes from origin to destination by public transportation in midday traffic; whole travel chain has been taken into account excluding the waiting time at home
    • pt_m_d: Distance in meters of the public transportation route in midday traffic
    • car_r_t: Travel time in minutes from origin to destination by private car in rush hour traffic; the whole travel chain has been taken into account
    • car_r_d: Distance in meters of the private car route in rush hour traffic
    • car_m_t: Travel time in minutes from origin to destination by private car in midday traffic; the whole travel chain has been taken into account
    • car_m_d: Distance in meters of the private car route in midday traffic
    • car_sl_t: Travel time from origin to destination by private car following speed limits without any additional impedances; the whole travel chain has been taken into account

    METHODS

    For detailed documentation and how to reproduce the data, see HelsinkiRegionTravelTimeMatrix2018 GitHub repository.

    THE ROUTE BY CAR have been calculated with a dedicated open source tool called DORA (DOor-to-door Routing Analyst) developed for this project. DORA uses PostgreSQL database with PostGIS extension and is based on the pgRouting toolkit. MetropAccess-Digiroad (modified from the original Digiroad data provided by Finnish Transport Agency) has been used as a street network in which the travel times of the road segments are made more realistic by adding crossroad impedances for different road classes.

    The calculations have been repeated for two times of the day using 1) the “midday impedance” (i.e. travel times outside rush hour) and 2) the “rush hour impendance” as impedance in the calculations. Moreover, there is 3) the “speed limit impedance” calculated in the matrix (i.e. using speed limit without any additional impedances).

    The whole travel chain (“door-to-door approach”) is taken into account in the calculations:
    1) walking time from the real origin to the nearest network location (based on Euclidean distance),
    2) average walking time from the origin to the parking lot,
    3) travel time from parking lot to destination,
    4) average time for searching a parking lot,
    5) walking time from parking lot to nearest network location of the destination and
    6) walking time from network location to the real destination (based on Euclidean distance).

    THE ROUTES BY PUBLIC TRANSPORTATION have been calculated by using the MetropAccess-Reititin tool which also takes into account the whole travel chains from the origin to the destination:
    1) possible waiting at home before leaving,
    2) walking from home to the transit stop,
    3) waiting at the transit stop,
    4) travel time to next transit stop,
    5) transport mode change,
    6) travel time to next transit stop and
    7) walking to the destination.

    Travel times by public transportation have been optimized using 10 different departure times within the calculation hour using so called Golomb ruler. The fastest route from these calculations are selected for the final travel time matrix.

    THE ROUTES BY CYCLING are also calculated using the DORA tool. The network dataset underneath is MetropAccess-CyclingNetwork, which is a modified version from the original Digiroad data provided by Finnish Transport Agency. In the dataset the travel times for the road segments have been modified to be more realistic based on Strava sports application data from the Helsinki region from 2016 and the bike sharing system data from Helsinki from 2017.

    For each road segment a separate speed value was calculated for slow and fast cycling. The value for fast cycling is based on a percentual difference between segment specific Strava speed value and the average speed value for the whole Strava data. This same percentual difference has been applied to calculate the slower speed value for each road segment. The speed value is then the average speed value of bike sharing system users multiplied by the percentual difference value.

    The reference value for faster cycling has been 19km/h, which is based on the average speed of Strava sports application users in the Helsinki region. The reference value for slower cycling has been 12km/, which has been the average travel speed of bike sharing system users in Helsinki. Additional 1 minute have been added to the travel time to consider the time for taking (30s) and returning (30s) bike on the origin/destination.

    More information of the Strava dataset that was used can be found from the Cycling routes and fluency report, which was published by us and the city of Helsinki.

    THE ROUTES BY WALKING were also calculated using the MetropAccess-Reititin by disabling all motorized transport modesin the calculation. Thus, all routes are based on the Open Street Map geometry.

    The walking speed has been adjusted to 70 meters per minute, which is the default speed in the HSL Journey Planner (also in the calculations by public transportation).

    All calculations were done using the computing resources of CSC-IT Center for Science (https://www.csc.fi/home).

  17. Math Formula Retrieval

    • kaggle.com
    • huggingface.co
    zip
    Updated Dec 2, 2023
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    The Devastator (2023). Math Formula Retrieval [Dataset]. https://www.kaggle.com/datasets/thedevastator/math-formula-pair-classification-dataset/data
    Explore at:
    zip(2021716728 bytes)Available download formats
    Dataset updated
    Dec 2, 2023
    Authors
    The Devastator
    License

    https://creativecommons.org/publicdomain/zero/1.0/https://creativecommons.org/publicdomain/zero/1.0/

    Description

    Math Formula Retrieval

    Math Formula Pair Classification Dataset

    By ddrg (From Huggingface) [source]

    About this dataset

    With a total of six columns, including formula1, formula2, label (binary format), formula1, formula2, and label, the dataset provides all the necessary information for conducting comprehensive analysis and evaluation.

    The train.csv file contains a subset of the dataset specifically curated for training purposes. It includes an extensive range of math formula pairs along with their corresponding labels and unique ID names. This allows researchers and data scientists to construct models that can predict whether two given formulas fall within the same category or not.

    On the other hand, test.csv serves as an evaluation set. It consists of additional pairs of math formulas accompanied by their respective labels and unique IDs. By evaluating model performance on this test set after training it on train.csv data, researchers can assess how well their models generalize to unseen instances.

    By leveraging this informative dataset, researchers can unlock new possibilities in mathematics-related fields such as pattern recognition algorithms development or enhancing educational tools that involve automatic identification and categorization tasks based on mathematical formulas

    How to use the dataset

    Introduction

    Dataset Description

    train.csv

    The train.csv file contains a set of labeled math formula pairs along with their corresponding labels and formula name IDs. It consists of the following columns: - formula1: The first mathematical formula in the pair (text). - formula2: The second mathematical formula in the pair (text). - label: The classification label indicating whether the pair of formulas belong to the same category or not (binary). A label value of 1 indicates that both formulas belong to the same category, while a label value of 0 indicates different categories.

    test.csv

    The purpose of the test.csv file is to provide a set of formula pairs along with their labels and formula name IDs for testing and evaluation purposes. It has an identical structure to train.csv, containing columns like formula1, formula2, label, etc.

    Task

    The main task using this dataset is binary classification, where your objective is to predict whether two mathematical formulas belong to the same category or not based on their textual representation. You can use various machine learning algorithms such as logistic regression, decision trees, random forests, or neural networks for training models on this dataset.

    Exploring & Analyzing Data

    Before building your model, it's crucial to explore and analyze your data. Here are some steps you can take:

    • Load both CSV files (train.csv and test.csv) into your preferred data analysis framework or programming language (e.g., Python with libraries like pandas).
    • Examine the dataset's structure, including the number of rows, columns, and data types.
    • Check for missing values in the dataset and handle them accordingly.
    • Visualize the distribution of labels to understand whether it is balanced or imbalanced.

    Model Building

    Once you have analyzed and preprocessed your dataset, you can start building your classification model using various machine learning algorithms:

    • Split your train.csv data into training and validation sets for model evaluation during training.
    • Choose a suitable

    Research Ideas

    • Math Formula Similarity: This dataset can be used to develop a model that classifies whether two mathematical formulas are similar or not. This can be useful in various applications such as plagiarism detection, identifying duplicate formulas in databases, or suggesting similar formulas based on user input.
    • Formula Categorization: The dataset can be used to train a model that categorizes mathematical formulas into different classes or categories. For example, the model can classify formulas into algebraic expressions, trigonometric equations, calculus problems, or geometric theorems. This categorization can help organize and search through large collections of mathematical formulas.
    • Formula Recommendation: Using this dataset, one could build a recommendation system that suggests related math formulas based on user input. By analyzing the similarities between different formula pairs and their corresponding labels, the system could provide recommendations for relevant mathematical concepts that users may need while solving problems or studying specific topics in mathematics

    Acknowle...

  18. S

    Python numerical computation code for the article of "Numerical study of...

    • scidb.cn
    Updated Jun 6, 2025
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    Lu Kun (2025). Python numerical computation code for the article of "Numerical study of superradiance and Hawking radiation of rotating acoustic black holes" [Dataset]. http://doi.org/10.57760/sciencedb.24506
    Explore at:
    CroissantCroissant is a format for machine-learning datasets. Learn more about this at mlcommons.org/croissant.
    Dataset updated
    Jun 6, 2025
    Dataset provided by
    Science Data Bank
    Authors
    Lu Kun
    License

    https://api.github.com/licenses/mithttps://api.github.com/licenses/mit

    Description

    This dataset contains Python numerical computation code for studying the phenomena of acoustic superluminescence and Hawking radiation in specific rotating acoustic black hole models. The code is based on the radial wave equation of scalar field (acoustic disturbance) under the effective acoustic metric background derived from analysis. Dataset generation process and processing methods: The core code is written in Python language, using standard scientific computing libraries NumPy and SciPy. The main steps include: (1) defining model parameters (such as A, B, m) and calculation range (frequency $\ omega $from 0.01 to 2.0, turtle coordinates $r ^ * $from -20 to 20); (2) Implement the mutual conversion function between the radial coordinate $r $and the turtle coordinate $r ^ * $, where the inversion of $r ^ * (r) $is numerically solved using SciPy's' optimize.root_scalar 'function (such as Brent's method), and special attention is paid to calculations near the horizon $r_H=| A |/c $to ensure stability; (3) Calculate the effective potential $V_0 (r ^ *, \ omega) $that depends on $r (r ^ *) $; (4) Convert the second-order radial wave equation into a system of quaternion first-order real valued ordinary differential equations; (5) The ODE system was solved using SciPy's' integrate. solve_ivp 'function (using an adaptive step size RK45 method with relative and absolute error margins set to $10 ^ {-8} $), applying pure inward boundary conditions (normalized unit transmission) at the field of view and asymptotic behavior at infinity; (6) Extract the reflection coefficient $\ mathcal {R} $and transmission coefficient $\ mathcal {T} $from the numerical solution; (7) Calculate the Hawking radiation power spectrum $P_ \ omega $based on the derived Hawking temperature $TH $, event horizon angular velocity $\ Omega-H $, Bose Einstein statistics, and combined with the gray body factor $| \ mathcal {T} | ^ 2 $. The calculation process adopts the natural unit system ($\ hbar=k_B=c=1 $) and sets the feature length $r_0=1 $. Dataset content: This dataset mainly includes a Python script file (code for numerical research on superluminescence and Hawking radiation of rotating acoustic black holes. py) and a README documentation file (README. md). The Python script implements the complete calculation process mentioned above. The README file provides a detailed explanation of the code's functionality, the required dependency libraries (Python 3, NumPy, SciPy) for running, the running methods, and the meaning of parameters. This dataset does not contain any raw experimental data and is only theoretical calculation code. Data accuracy and validation: The reliability of the code has been validated through two key indicators: (1) Flow conservation relationship$|\ mathcal{R}|^2 + [(\omega-m\Omega_H)/\omega]|\mathcal{T}|^2 = 1$ The numerical approximation holds within the calculated frequency range (with a deviation typically on the order of $10 ^ {-8} $or less); (2) Under the condition of superluminescence $0<\ omega1 $, which is consistent with theoretical expectations. File format and software: The code is in standard Python 3 (. py) format and can run in any standard Python 3 environment with NumPy and SciPy libraries installed. The README file is in Markdown (. md) format and can be opened with any text editor or Markdown viewer. No special or niche software is required.

  19. e

    Data from: Analysis of the Scalar and Vector Random Coupling Models For a...

    • data.europa.eu
    • demo.researchdata.se
    • +2more
    unknown
    Updated Sep 11, 2023
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    Chalmers tekniska högskola (2023). Analysis of the Scalar and Vector Random Coupling Models For a Four Coupled-Core Fiber [Dataset]. https://data.europa.eu/data/datasets/https-doi-org-10-5281-zenodo-7895952~~1?locale=mt
    Explore at:
    unknownAvailable download formats
    Dataset updated
    Sep 11, 2023
    Dataset authored and provided by
    Chalmers tekniska högskola
    Description

    The files with simulation results for ECOC 20223 submission "Analysis of the Scalar and Vector Random Coupling Models For a Four Coupled-Core Fiber". "4CCF_eigenvectorsPol" file is the Mathematica code which enables to calculate supermodes (eigenvectors of M(w)) and their propagation constants of 4-coupled-core fiber (4CCF). These results are uploaded to the python notebook "4CCF_modelingECOC" in order to plot them to get Fig. 2 in the paper. "TransferMatrix" is the python file with functions used for modeling, simulation and plotting. It is also uploaded in the python notebook "4CCF_modelingECOC", where all the calculations for figures in the paper are presented.

    ! UPD 25.09.2023: There is an error in the formula of birefringence calculation. It is in the function "CouplingCoefficients" in "TransferMatrix" file. There the variable "birefringence" has to be calculated according to the formula (19) [A. Ankiewicz, A. Snyder, and X.-H. Zheng, "Coupling between parallel optical fiber cores–critical examination", Journal of Lightwave Technology, vol. 4, no. 9,pp. 1317–1323, 1986]: (4*U**2*W*spec.k0(W)*spec.kn(2, W_)/(spec.k1(W)*V**4))*((spec.iv(1, W)/spec.k1(W))-(spec.iv(2, W)/spec.k0(W))) The correct formula gives almost the same result (the difference is 10^-5), but one has to use a correct formula anyway. ! UPD 9.12.2023: I have noticed that in the published version of the code I forgot to change the wavelength range for impulse response calculation. So instead of seeing the nice shape as in the paper you will see resolution limited shape. To solve that just change the range of wavelengths, you can add "wl = [1545e-9, 1548e-9]" in the first cell after "Total power impulse response". P.s. In case of any questions or suggestions you are welcome to write me an email ekader@chalmers.se

  20. Estimated stand-off distance between ADS-B equipped aircraft and obstacles

    • zenodo.org
    • data.niaid.nih.gov
    • +1more
    jpeg, zip
    Updated Jul 12, 2024
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    Andrew Weinert; Andrew Weinert (2024). Estimated stand-off distance between ADS-B equipped aircraft and obstacles [Dataset]. http://doi.org/10.5281/zenodo.7741273
    Explore at:
    zip, jpegAvailable download formats
    Dataset updated
    Jul 12, 2024
    Dataset provided by
    Zenodohttp://zenodo.org/
    Authors
    Andrew Weinert; Andrew Weinert
    License

    Attribution-NonCommercial-NoDerivs 4.0 (CC BY-NC-ND 4.0)https://creativecommons.org/licenses/by-nc-nd/4.0/
    License information was derived automatically

    Description

    Summary:

    Estimated stand-off distance between ADS-B equipped aircraft and obstacles. Obstacle information was sourced from the FAA Digital Obstacle File and the FHWA National Bridge Inventory. Aircraft tracks were sourced from processed data curated from the OpenSky Network. Results are presented as histograms organized by aircraft type and distance away from runways.

    Description:

    For many aviation safety studies, aircraft behavior is represented using encounter models, which are statistical models of how aircraft behave during close encounters. They are used to provide a realistic representation of the range of encounter flight dynamics where an aircraft collision avoidance system would be likely to alert. These models currently and have historically have been limited to interactions between aircraft; they have not represented the specific interactions between obstacles and aircraft equipped transponders. In response, we calculated the standoff distance between obstacles and ADS-B equipped manned aircraft.

    For robustness, this assessment considered two different datasets of manned aircraft tracks and two datasets of obstacles. For robustness, MIT LL calculated the standoff distance using two different datasets of aircraft tracks and two datasets of obstacles. This approach aligned with the foundational research used to support the ASTM F3442/F3442M-20 well clear criteria of 2000 feet laterally and 250 feet AGL vertically.

    The two datasets of processed tracks of ADS-B equipped aircraft curated from the OpenSky Network. It is likely that rotorcraft were underrepresented in these datasets. There were also no considerations for aircraft equipped only with Mode C or not equipped with any transponders. The first dataset was used to train the v1.3 uncorrelated encounter models and referred to as the “Monday” dataset. The second dataset is referred to as the “aerodrome” dataset and was used to train the v2.0 and v3.x terminal encounter model. The Monday dataset consisted of 104 Mondays across North America. The other dataset was based on observations at least 8 nautical miles within Class B, C, D aerodromes in the United States for the first 14 days of each month from January 2019 through February 2020. Prior to any processing, the datasets required 714 and 847 Gigabytes of storage. For more details on these datasets, please refer to "Correlated Bayesian Model of Aircraft Encounters in the Terminal Area Given a Straight Takeoff or Landing" and “Benchmarking the Processing of Aircraft Tracks with Triples Mode and Self-Scheduling.”

    Two different datasets of obstacles were also considered. First was point obstacles defined by the FAA digital obstacle file (DOF) and consisted of point obstacle structures of antenna, lighthouse, meteorological tower (met), monument, sign, silo, spire (steeple), stack (chimney; industrial smokestack), transmission line tower (t-l tower), tank (water; fuel), tramway, utility pole (telephone pole, or pole of similar height, supporting wires), windmill (wind turbine), and windsock. Each obstacle was represented by a cylinder with the height reported by the DOF and a radius based on the report horizontal accuracy. We did not consider the actual width and height of the structure itself. Additionally, we only considered obstacles at least 50 feet tall and marked as verified in the DOF.

    The other obstacle dataset, termed as “bridges,” was based on the identified bridges in the FAA DOF and additional information provided by the National Bridge Inventory. Due to the potential size and extent of bridges, it would not be appropriate to model them as point obstacles; however, the FAA DOF only provides a point location and no information about the size of the bridge. In response, we correlated the FAA DOF with the National Bridge Inventory, which provides information about the length of many bridges. Instead of sizing the simulated bridge based on horizontal accuracy, like with the point obstacles, the bridges were represented as circles with a radius of the longest, nearest bridge from the NBI. A circle representation was required because neither the FAA DOF or NBI provided sufficient information about orientation to represent bridges as rectangular cuboid. Similar to the point obstacles, the height of the obstacle was based on the height reported by the FAA DOF. Accordingly, the analysis using the bridge dataset should be viewed as risk averse and conservative. It is possible that a manned aircraft was hundreds of feet away from an obstacle in actuality but the estimated standoff distance could be significantly less. Additionally, all obstacles are represented with a fixed height, the potentially flat and low level entrances of the bridge are assumed to have the same height as the tall bridge towers. The attached figure illustrates an example simulated bridge.

    It would had been extremely computational inefficient to calculate the standoff distance for all possible track points. Instead, we define an encounter between an aircraft and obstacle as when an aircraft flying 3069 feet AGL or less comes within 3000 feet laterally of any obstacle in a 60 second time interval. If the criteria were satisfied, then for that 60 second track segment we calculate the standoff distance to all nearby obstacles. Vertical separation was based on the MSL altitude of the track and the maximum MSL height of an obstacle.

    For each combination of aircraft track and obstacle datasets, the results were organized seven different ways. Filtering criteria were based on aircraft type and distance away from runways. Runway data was sourced from the FAA runways of the United States, Puerto Rico, and Virgin Islands open dataset. Aircraft type was identified as part of the em-processing-opensky workflow.

    • All: No filter, all observations that satisfied encounter conditions
    • nearRunway: Aircraft within or at 2 nautical miles of a runway
    • awayRunway: Observations more than 2 nautical miles from a runway
    • glider: Observations when aircraft type is a glider
    • fwme: Observations when aircraft type is a fixed-wing multi-engine
    • fwse: Observations when aircraft type is a fixed-wing single engine
    • rotorcraft: Observations when aircraft type is a rotorcraft

    License

    This dataset is licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International(CC BY-NC-ND 4.0).

    This license requires that reusers give credit to the creator. It allows reusers to copy and distribute the material in any medium or format in unadapted form and for noncommercial purposes only. Only noncommercial use of your work is permitted. Noncommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. Exceptions are given for the not for profit standards organizations of ASTM International and RTCA.

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Sonja Preuss; Matthew Low; Anna Cassel-Lundhagen; Åsa Berggren (2015). Evaluating range-expansion models for calculating nonnative species’ expansion rate [Dataset]. http://doi.org/10.5061/dryad.ns624

Data from: Evaluating range-expansion models for calculating nonnative species’ expansion rate

Related Article
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Dataset updated
Apr 28, 2015
Dataset provided by
Swedish University of Agricultural Sciences
Authors
Sonja Preuss; Matthew Low; Anna Cassel-Lundhagen; Åsa Berggren
License

https://spdx.org/licenses/CC0-1.0.htmlhttps://spdx.org/licenses/CC0-1.0.html

Area covered
Sweden
Description
  1. Species range shifts associated with environmental change or biological invasions are increasingly important study areas. However, quantifying range expansion rates may be heavily influenced by methodology and/or sampling bias. 2. We compared expansion rate estimates of Roesel’s bush-cricket (Metrioptera roeselii, Hagenbach 1822), a non-native species currently expanding its range in south-central Sweden, from range statistic models based on distance measures (mean, median, 95th gamma quantile, marginal mean, maximum and conditional maximum) and an area-based method (grid occupancy). We used sampling simulations to determine the sensitivity of the different methods to incomplete sampling across the species’ range. 3. For periods when we had comprehensive survey data, range expansion estimates clustered into two groups: (i) those calculated from range margin statistics (gamma, marginal mean, maximum and conditional maximum: ~3 km/yr), and (ii) those calculated from the central tendency (mean and median) and the area-based method of grid occupancy (~1.5 km/yr). 4. Range statistic measures differed greatly in their sensitivity to sampling effort; the proportion of sampling required to achieve an estimate within 10% of the true value ranged from 0.17-0.9. Grid occupancy and median were most sensitive to sampling effort, and the maximum and gamma quantile the least. 5. If periods with incomplete sampling were included in the range expansion calculations, this generally lowered the estimates (range 16-72%), with exception of the gamma quantile that was slightly higher (6%). 6. Care should be taken when interpreting rate expansion estimates from data sampled from only a fraction of the full distribution. Methods based on the central tendency will give rates approximately half that of methods based on the range margin. The gamma quantile method appears to be the most robust to incomplete sampling bias and should be considered as the method of choice when sampling the entire distribution is not possible.
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