TPVTrack v1.0: a watershed segmentation and overlap correspondence method for tracking tropopause polar vortices

Abstract. A new free modular software package is described for tracking tropopause polar vortices (TPVs) natively on structured or unstructured grids. Motivated by limitations in spatial characterization and time tracking within existing approaches, TPVTrack mimics the expected dynamics of TPVs to represent their (1) spatial structure, with variable shapes and intensities, and (2) time evolution, with mergers and splits. TPVs are segmented from the gridded flow field into spatial objects as restricted regional watershed basins on the tropopause, described by geometric metrics, associated over time by overlap similarity into major and minor correspondences, and tracked along major correspondences. Simplified segmentation and correspondence test cases illustrate some of the appeal, sensitivities, and limitations of TPVTrack, including effective representation of spatial shape and reduced false positive associations in time. Tracked TPVs in more realistic historical conditions are consistent in bulk with expectations of life cycle and mean structure. Individual tracks are less reliable when discriminating among multiple overlaps. Modifications to track other physical features are possible, with each application requiring evaluation.

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TPVTrack v1.0: A watershed segmentation and overlap correspondence method for tracking tropopause polar vortices

10.5194/gmd-2018-180 ◽

2018 ◽

Author(s):

Nicholas Szapiro ◽

Steven Cavallo

Keyword(s):

Software Package ◽

Unstructured Grids ◽

Free Software ◽

Test Cases ◽

Watershed Segmentation ◽

Spatial Characterization ◽

Mean Structure ◽

Spatial Shape ◽

Physical Features ◽

Effective Representation

Abstract. A new modular, free software package is described for tracking tropopause polar vortices (TPVs) natively on structured or unstructured grids. Motivated by limitations in spatial characterization and time tracking within existing approaches, TPVTrack leverages the dynamics of TPVs to represent their (1) spatial structure, with variable shapes and intensities and (2) time evolution, with mergers and splits. TPVs are segmented from the gridded flow field into spatial objects as restricted regional watershed basins on the tropopause, described by geometric metrics, associated over time by overlap similarity into major and minor correspondences, and tracked along major correspondences. Simplified segmentation and correspondence test cases illustrate some of the appeal, sensitivities, and limitations of TPVTrack, including effective representation of spatial shape and reduced false positive associations in time. Tracked TPVs in more realistic historical conditions are consistent in bulk with expectations of life cycle and mean structure. Individual tracks are less reliable when discriminating between multiple overlaps. Modifications to track other physical features are possible, with each application requiring evaluation.

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C hem S hell—a modular software package for QM / MM simulations

Wiley Interdisciplinary Reviews Computational Molecular Science ◽

10.1002/wcms.1163 ◽

2013 ◽

Vol 4 (2) ◽

pp. 101-110 ◽

Cited By ~ 167

Author(s):

Sebastian Metz ◽

Johannes Kästner ◽

Alexey A. Sokol ◽

Thomas W. Keal ◽

Paul Sherwood

Keyword(s):

Software Package ◽

Modular Software

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Description and Classification of Balti Consonant Stop Sounds

Linguistics and Literature Review ◽

10.32350/llr.61.01 ◽

2020 ◽

Vol 6 (1) ◽

pp. 1-8

Author(s):

Ghulam Abbas ◽

Muhammad Bashir

Keyword(s):

Software Package ◽

Speech Analysis ◽

Degree Programs ◽

Government College ◽

Physical Features ◽

Gilgit Baltistan ◽

Purposive Sample

The study aims to describe and classify consonant stop sounds of the Balti language, which is spoken in Gilgit-Baltistan, Pakistan. In order to describe and classify these sounds, 120 words were selected from literature written in the Balti language. A purposive sample of 20 Balti speakers from 16 to 35 years of age, who were studying in various degree programs at Government College for Boys, Model Town, Lahore and University of Management and Technology, Lahore, was selected to record possible Balti consonant stop sounds. The physical features of each consonant stop sound were carried through the software package for speech analysis in phonetics. The study reveals that there are 15 consonant stop sounds in the Balti language. The study helps document the Balti language, which follows mostly a verbal tradition like many other languages of the region.

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Development of the flow part of reactive type HPC of K-325-23,5 series steam turbine based on the use of modern computer technologies

Journal of Mechanical Engineering ◽

10.15407/pmach2021.04.006 ◽

2021 ◽

Vol 24 (4) ◽

pp. 6-16

Author(s):

Andrii V. Rusanov ◽

◽

Viktor H. Subotin ◽

Viktor L. Shvetsov ◽

Roman A. Rusanov ◽

...

Keyword(s):

Steam Turbine ◽

Turbulent Flows ◽

Software Package ◽

High Pressure Cylinder ◽

Modern Computer ◽

Gas Dynamic ◽

Analytical Construction ◽

Pressure Cylinder ◽

Flow Part ◽

Spatial Shape

The results of gas-dynamic design of a new flow part of a reactive type high-pressure cylinder (HPC) of the K-300 series condensing steam turbine are presented. The turbine was developed using a comprehensive methodology implemented in the IPMFlow software package. The methodology includes gas-dynamic calculations of various levels of complexity, as well as methods for analytical construction of the spatial shape of the blade rows based on a limited number of parameterized values. The real thermodynamic properties of water and steam were taken into account in 3D calculations of turbulent flows. At the final stage, 3D end-to-end calculations of the HPC, which consists of 18 stages, were carried out. The technology of parallel computing was applied in the said calculations. It is shown that a significant increase in efficiency and power has been achieved in the developed HPC due to the use of reactive type stages with modern smooth blade profiles and monotonic meridional contours.

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A systematized approach to AVHRR image navigation

Annals of Glaciology ◽

10.3189/s0260305500013185 ◽

1993 ◽

Vol 17 ◽

pp. 414-420 ◽

Cited By ~ 1

Author(s):

D.G. Baldwin ◽

W.J. Emery

Keyword(s):

Software Package ◽

Systematic Approach ◽

Control Point ◽

Registration Accuracy ◽

Registration Errors ◽

Modular Software ◽

Image Navigation ◽

Current Systems ◽

Different Sources ◽

Very High

Accurate co-location and geo-registration of AVHRR (Advanced Very High Resolution Radiometer) is necessary for most applications involving these data. To obtain the necessary accuracy, most of the current systems available for AVHRR image rectification require corrections to errors arising from several different sources. This paper presents a software package which is able to correct registration errors from all sources using effective roll, pitch, and yaw values determined from ground control point offsets. These effective values are used to establish a baseline registration against which other models are compared. Spacecraft and sampling geometry are revisited in order to systemize and better define the procedure of AVHRR geo-registration. This systematic approach has resulted in a modular software package which has a registration accuracy of 1 satellite pixel, and is easily modified and improved.

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Gridless Adaptive Method for Simulating Unsteady Flows with Moving Shocks

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.271-272.948 ◽

2012 ◽

Vol 271-272 ◽

pp. 948-952

Author(s):

Sai Hu Pu

Keyword(s):

High Resolution ◽

Numerical Test ◽

Unsteady Flows ◽

Adaptive Method ◽

Test Cases ◽

Computational Domain ◽

Local Pressure ◽

Time Step ◽

Physical Features ◽

Cloud Of Points

In this paper, the gridless adaptive method is extended to simulate unsteady flows with moving shocks. In order to capture physical features like moving shocks with local high resolution, a technique of dynamic cloud of points is achieved by adopting clouds refinement and clouds coarsening procedures during the evolution of the unsteady flows. The regions for clouds refinement and clouds coarsening are determined at every time step by an indicator, which is defined as a function of the local pressure gradient. Once the regions of cloud of points to be adjusted are located by the indicator, the clouds refinement is carried out by introducing new points based on the existing structure of cloud of points, and the clouds coarsening procedure is also implemented simultaneously in order to control the size of the points distributed in the whole computational domain. The numerical test cases show that the gridless adaptive method presented can capture moving shocks with high resolution successfully in both inviscid and viscous test cases.

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Modeling Friction Wedges: Part I — The State-of-the-Art

Rail Transportation ◽

10.1115/imece2004-61094 ◽

2004 ◽

Cited By ~ 1

Author(s):

Peter E. Klauser

Keyword(s):

Vehicle Dynamics ◽

Software Package ◽

State Of The Art ◽

Current Approach ◽

The State ◽

Test Cases ◽

Critical Component ◽

Technology Center ◽

Future Work

The friction wedge is a critical component in the three-piece truck. This paper describes the current approach for modeling friction wedges and compares its implementation in the commercially available NUCARS™ and VAMPIRE® vehicle dynamics codes. NUCARS™ is a software package developed by Transportation Technology Center, Inc., while VAMPIRE® is a package developed by AEA Technology plc. Sample results from both codes are presented based on standalone test cases. Shortcomings of the “state-of-the-art” model are described and directions for future work are proposed.

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Localizer: fast, accurate, open-source, and modular software package for superresolution microscopy

Journal of Biomedical Optics ◽

10.1117/1.jbo.17.12.126008 ◽

2012 ◽

Vol 17 (12) ◽

pp. 126008 ◽

Cited By ~ 99

Author(s):

Peter Dedecker ◽

Sam Duwé ◽

Robert K. Neely ◽

Jin Zhang

Keyword(s):

Open Source ◽

Software Package ◽

Superresolution Microscopy ◽

Modular Software

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Cutting Path Optimization Using Tabu Search

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.473.739 ◽

2011 ◽

Vol 473 ◽

pp. 739-748 ◽

Cited By ~ 14

Author(s):

Reginald Dewil ◽

Pieter Vansteenwegen ◽

Dirk Cattrysse

Keyword(s):

Tabu Search ◽

Software Package ◽

Feasible Solution ◽

Test Cases ◽

Finish Cutting ◽

Initial Feasible Solution ◽

Commercial Software Package ◽

Cutter Head ◽

Cutting Path ◽

The Given

This paper deals with generating paths for cutting irregular parts nested on a metal sheet. The objective is to minimize the total non-cutting time for the cutter head starting at a known location, cutting all the required elements and returning to the known location. In contrast to most literature on this topic, a part does not have to be cut at once. If this reduces the total non-cutting time, it is possible to cut a number of elements on a given part, then cut other parts and then return later to finish cutting the given part. The problem is modeled as a generalized traveling salesperson problem with special precedence constraints. An initial feasible solution is generated and improved by local moves embedded in a tabu search framework. The proposed algorithm shows promising results in comparison with a commercial software package on a limited set of test cases.

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