Journal articles on the topic 'Polar charts'
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Wen, Chao Jiang, Hong Wei Bian, Xin Gao, and Rong Ying Wang. "Availability Analysis of Mercator Projection in Nautical Charts' Compilation in Polar Regions." Applied Mechanics and Materials 535 (February 2014): 556–61. http://dx.doi.org/10.4028/www.scientific.net/amm.535.556.
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Availability of Mercator projection in polar regions mainly suffers from gross scale error and only can be improved by control of scale error; methods of scale error control such as properly adjusting of standard parallels, appropriately defining and relaxing acceptable scale error thresholds together with adopting appropriate chart scales and sheet specifications are presented; appropriate acceptable scale error thresholds are discussed by referring to domestic and abroad chart compilation specifications and existing Russian polar nautical charts; availability of Mercator projection in latitudes of 75°~85°is analyzed on charts with various standard parallels, scale error thresholds and latitude ranges, the result indicates that Mecator projection still satisfies compiling requirements of nautical charts with commonly used scales and sheet specifications in latitudes between 75°and 85°.
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BENEDITO, MIGUEL ANGEL PEREZ. "Explaining Accounting Structures Changes by Applying the Accounting Methodology of Radar-Polar Chart." Archives of Business Research 10, no. 5 (May 12, 2022): 39–64. http://dx.doi.org/10.14738/abr.105.12289.
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The manuscript analyzes the relationship between the dynamic activity of entities and its effects on accounting structures of their financial statements. Radar charts and tetragrams visually represent the dynamic activity of features, respectively. To overcome discrepancies in qualitative and quantitative comparative analysis, the manuscript introduces polar equation parameters that drive research towards qualitative analysis. Classes of management – kinds and types - are conductor threads for explaining relations between charts and diagrams, and level of employment as well as market prices are environment variables for confirming hypothesis of manuscript. The Euclidean distances of the accounting relative centers in the tetragrams and the management optima are indicators developed for both stakeholders and managers to explain the evolution of decision making over time. The accounting applied is an economic science.
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Carroll, William M. "Using a Polar Coordinate System in the Classroom." Arithmetic Teacher 37, no. 8 (April 1990): 42–45. http://dx.doi.org/10.5951/at.37.8.0042.
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Most elementary school students have experiences with a rectangular graphing system that helps to prepare them for ideas in algebra and analytic geometry. Mathematics books at the elementary school level contain a section on graphing, though it is often one of the later chapters, where it may be treated as supplementary material. In science and in social studies, students may find various data graphed or may have a project in which they have to graph daily temperatures, rainfall, or test scores. Biorhythms, record sales charts, or, for the more ambitious, the daily stock market give additional exposure. Designing graphics on the computer monitor often requires some placement by a rectangular coordinate system. By the time students meet the Cartesian coordinate system with its x- and y-axes and use it to graph equations, the idea and techniques should be somewhat familiar.
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Song, Min, Minhyuk Lee, Taesung Park, and Mira Park. "MP-LASSO chart: a multi-level polar chart for visualizing group LASSO analysis of genomic data." Genomics & Informatics 20, no. 4 (December 31, 2022): e48. http://dx.doi.org/10.5808/gi.22075.
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Penalized regression has been widely used in genome-wide association studies for joint analyses to find genetic associations. Among penalized regression models, the least absolute shrinkage and selection operator (LASSO) method effectively removes some coefficients from the model by shrinking them toward zero. To handle group structures, such as genes and pathways, several modified LASSO penalties have been proposed, including group LASSO and sparse group LASSO. Group LASSO ensures sparsity at the level of pre-defined groups, eliminating unimportant groups. Sparse group LASSO performs group selection as in group LASSO, but also performs individual selection as in LASSO. While these sparse methods are useful in high-dimensional genetic studies, interpreting the results with many groups and coefficients is not straightforward. LASSO's results are often expressed as trace plots of regression coefficients. However, few studies have explored the systematic visualization of group information. In this study, we propose a multi-level polar LASSO (MP-LASSO) chart, which can effectively represent the results from group LASSO and sparse group LASSO analyses. An R package to draw MP-LASSO charts was developed. Through a real-world genetic data application, we demonstrated that our MP-LASSO chart package effectively visualizes the results of LASSO, group LASSO, and sparse group LASSO.
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McConnell, Anita. "Surveying terrestrial magnetism in time and space." Archives of Natural History 32, no. 2 (October 2005): 346–60. http://dx.doi.org/10.3366/anh.2005.32.2.346.
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Charts marked with the lines of magnetic variation have been published since Halley's Atlantic chart of 1701. It was already known that the location of the magnetic poles shifted over time, and that the north and south poles were not diametrically opposite. As more seafarers penetrated the Southern Ocean, isogons on the charts were extended southwards with greater confidence. At sea variation was measured by comparing compass direction with the Sun's midday shadow. In polar regions, where horizontal force is too weak to attract a compass needle, the location of the pole was sought by observing the inclination of a dip needle swinging in the magnetic meridian, which would hang vertically at the pole. The Fox dip circle, developed in 1834, was the first instrument capable of measuring dip and intensity at sea, and allowed James Clark Ross to predict the location of the South Magnetic Pole. In 1902 Discovery's crew landed an observatory ashore, but a trek on to the plateau failed to reach the magnetic pole. Success came in 1909 during Shackleton's Nimrod expedition, when T. Edgeworth David's party reached the zone of maximum dip. Over the following years data from photographic magnetometers recording declination, vertical and horizontal intensity were routinely made at the various national bases round Antarctica; they contributed to our knowledge of the Earth's internal magnetism and on the solar influences.
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Savours, Ann. "The first publication of The South Polar Times, Volume IV." Polar Record 50, no. 1 (May 22, 2013): 112. http://dx.doi.org/10.1017/s0032247413000259.
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Polar bibliophiles, librarians and readers will be familiar with the three handsome facsimile volumes of the first Antarctic newspaper, published in 1907 and 1914 and edited in turn by E. Shackleton, L.C. Bernacchi and A. Cherry-Garrard during the National Antarctic Expedition, 1901–1904 and the British Antarctic Expedition 1910–1913. These expeditions were led by Captain R.F. Scott R.N. in Discovery and Terra Nova respectively. From S.Y. Discovery, beset for two winters in the ice of McMurdo Sound were made the first extensive sledge journeys into the interior of the Antarctic continent, including the great ice sheet or plateau. These were further prolonged, following Shackleton's Nimrod expedition, while the pursuit of science during both Scott expeditions led to the publication in London of two monumental sets of scientific and geographical results, plus new charts and maps.
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Schröder, W., K. H. Wiederkehr, and K. Schlegel. "Georg von Neumayer and geomagnetic research." History of Geo- and Space Sciences 1, no. 2 (December 22, 2010): 77–87. http://dx.doi.org/10.5194/hgss-1-77-2010.
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Abstract. Neumayer was a prominent figure in the development of geophysics in the 19th century from a scientific as well as from an organisational point of view. In this paper we review and highlight his activities and efforts in geomagnetic research within five different aspects of geomagnetism: regional geomagnetic surveys, geomagnetic work in German naval observatories, geomagnetic investigations during the First Polar Year 1882/83, modifications of the Gaussian theory, and geomagnetic charts. In each field Neumayer was a researcher, a thinker, and a stimulating coordinator.
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Johnson, Art. "Now and Then: Displaying Data Is As Easy As Pie! Polar Area Graphs: Early Pie Charts." Mathematics Teaching in the Middle School 4, no. 6 (March 1999): 390–97. http://dx.doi.org/10.5951/mtms.4.6.0390.
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Imagine having to cut your household budget by 10 percent. Where would you make the cuts? Would you eat less food? Change the climate control in your home? Buy fewer new clothes? At times, we all must live on a budget and cut back on expenses. For Mark Conrad, these tasks are a bit more challenging. Mark is in charge of a $60 million school budget for Nashua, New Hampshire. When Nashua's mayor or the city council asks the board of education to cut expenses, Mark is at the center of debate about whether the cuts are even possible and where they might be made.
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Japaridze, Darejan, Marina Gigolashvili, and Vasili Kukhianidze. "Solar Differential Rotation of Compact Magnetic Elements and Polarity Reversal of the Sun." Proceedings of the International Astronomical Union 4, S257 (September 2008): 173–76. http://dx.doi.org/10.1017/s1743921309029251.
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AbstractThe differential rotation of the compact elements of the large-scale magnetic fields is studied using Solar Synoptic Charts (1966–1986). It is revealed that compact magnetic elements with the similar polarity of the polar magnetic field of the Sun have a larger rotation rate than the elements with the opposite polarity at all stages in the cycle.From the comparison of the experimental measuring data of the solar magnetic elements there are received the results: a) The differential rotations of the compact magnetic elements with negative and positive polarities have the similar behavior for the solar 20 and 21 cycles; b) It is established that in the rotation rate of compact magnetic elements there are present some variations at the time of polarity reversal of the Sun.There is assumed that the physical understanding of the connections of differential rotation of compact magnetic elements and polarity reversal of the Sun depends upon establishing a connection between the temporal variability of spatially resolved solar magnetic elements and polar reversals.
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Capelotti, P. J., and M. Forsberg. "The place names of Zemlya Frantsa-Iosifa: the Wellman polar expedition, 1898–1899." Polar Record 51, no. 6 (December 29, 2014): 624–36. http://dx.doi.org/10.1017/s0032247414000801.
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ABSTRACTIn 1898–1899, the first American polar expedition to Zemlya Frantsa-Iosifa [Franz Josef Land], under the leadership of journalist Walter Wellman, added at least forty place names to the islands, of which many survive on modern charts. These include the main discovery of the expedition, the large island named for Scottish-born Alexander Graham Bell, then president of the National Geographic Society, along with numerous smaller islands, capes and waterways. The origins of several of these names are now confirmed using recently discovered notes in the papers of Wellman's brother and business manager, Arthur Wellman. They demonstrate the close relationship between Walter Wellman and the political, financial and scientific elites of turn-of-the-century Chicago, Illinois, Washington, D.C., and the state of Ohio, associations derived from Wellman's profession as a Washington correspondent for Chicago newspapers.
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Callebaut, Dirk K., Valentine I. Makarov, and Ksenia S. Tavastsherna. "Large-Scale Patterns of Prominences in the Global Solar Cycles During 1880–1995." International Astronomical Union Colloquium 167 (1998): 442–45. http://dx.doi.org/10.1017/s0252921100048077.
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AbstractThe zonal distribution of prominences, their poleward migration from the sunspot zone to the poles, the polar magnetic field reversals and a correlation of the mean latitude of filament bands at minimum activity with the maximum of Wolf number in the next cycle are briefly discussed for the period 1880–1995. The need for research on the longterm latitude distribution of the prominences is emphasized. New results concerning long-term variations of the torsional oscillations of the Sun and quasi-periodic oscillations of the latitude zonal boundaries from an analysis of Hα charts (1915–1990) are given.
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Stern, Harry L. "Polar maps: Captain Cook and the earliest historical charts of the ice edge in the Chukchi Sea." Polar Geography 39, no. 4 (October 2016): 220–27. http://dx.doi.org/10.1080/1088937x.2016.1236845.
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Souliotis, Andreas, Katerina Giazitzi, and George Boskou. "Food safety benchmarking between retail outlets in Greece." Benchmarking: An International Journal 25, no. 7 (October 1, 2018): 2404–13. http://dx.doi.org/10.1108/bij-07-2017-0171.
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Purpose The purpose of this paper is to develop and implement methods for benchmarking the food safety and hygiene between retail outlets at the same time or at the same retail outlets at different times. Design/methodology/approach A tailor made questionnaire for the collection of food safety and hygiene remarks was designed to be applied in a large chain of retail outlets. The remarks were classified in the five categories of the Ishikawa model (materials, methods, personnel, equipment and environment). The retail outlets were located all over Greece and the audits were performed in a one-year term. Food safety experts were used as auditors after a six-month training period. The data collected were subject to analysis of the benchmarking scores and to cluster analysis to identify regions with similar food safety profiles. Findings Polar charts were used to illustrate the benchmarking scores for each of the five categories of evaluation per auditing period at the retail outlets. Another polar chart illustrates the benchmarking scores for each of the 12 regions of Greece. Cluster analysis demonstrates that some regions, like Ionian Islands and South Aegean, have similar profiles on food safety for the retail outlets. Originality/value The developed methodology can be used by retail companies with several outlets or by a group or an association of companies in order to identify problematic sectors and to set priorities while dealing with issues of food safety and hygiene. The work is limited to the Greek outlets but the methodology has potential application to every other country.
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Mahmood, Ramia M., and Ahmed Sami Hassan. "Determined Seasonal Variation of Polar Jet Streams over Baghdad City for period 2012-2014." Al-Mustansiriyah Journal of Science 31, no. 1 (March 1, 2020): 1. http://dx.doi.org/10.23851/mjs.v31i1.229.
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Analysis of the jet stream is diagnostic over Baghdad for period studies 2012 to 2014 using Radiosonde data and synoptic charts. The source of data is Iraq Meteorological Organization and Seismology (IMOS). Similar way for weather forecasts to identify areas, forecasters show that area has good predictability under jet stream case. The jet stream is happening clearly realized under the climatic conditions like temperature, humidity and geopotential height for upper layer. Two levels 300hPa and 500hPa is the best way to determine the current jet. Maximum frequency of jet stream happened in April and July in 500hPa that equal 13 times and in 300hPa happened 14 times in May. This study showed that the occurrence of cases of the jet stream is becoming increasingly volatile and decreasingly during 2012 and gradually increased in 2014 where that recorded in 2014.
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Makarov, V. I., and K. R. Sivaraman. "Global Evolution of Photospheric Magnetic Fields." Symposium - International Astronomical Union 138 (1990): 281–95. http://dx.doi.org/10.1017/s0074180900044247.
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The main features concerning the evolution of the large scale photospheric magnetic fields derived from synoptic maps as well as from H-alpha synoptic charts are reviewed. The significance of a variety of observations that indicate the presence of a high latitude component as a counterpart to the sunspot phenomenon at lower latitudes is reviewed. It is argued that these two components describe the global magnetic field on the sun. It is demonstrated that this scenario is able to link many phenomena observed on the sun (coronal emission, ephemeral active regions, geomagnetic activity, torsional oscillations, polar faculae and global modes in the magnetic field pattern) with the global magnetic activity.
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Phan, Dung T., Chao Liu, Murtadha J. AlTammar, Yanhui Han, and Younane N. Abousleiman. "Application of Artificial Intelligence To Predict Time-Dependent Mud-Weight Windows in Real Time." SPE Journal 27, no. 01 (October 26, 2021): 39–59. http://dx.doi.org/10.2118/206748-pa.
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Summary Selection of a safe mud weight is crucial in drilling operations to reduce costly wellbore-instability problems. Advanced physics models and their analytical solutions for mud-weight-window computation are available but still demanding in terms of central-processing-unit (CPU) time. This paper presents an artificial-intelligence (AI) solution for predicting time-dependent safe mud-weight windows and very refined polar charts in real time. The AI agents are trained and tested on data generated from a time-dependent coupled analytical solution (poroelastic) because numerical solutions are prohibitively slow. Different AI techniques, including linear regression, decision tree, random forest, extra trees, adaptive neuro fuzzy inference system (ANFIS), and neural networks are evaluated to select the most suitable one. The results show that neural networks have the best performances and are capable of predicting time-dependent mud-weight windows and polar charts as accurately as the analytical solution, with 1/1,000 of the computer time needed, making them very applicable to real-time drilling operations. The trained neural networks achieve a mean squared error (MSE) of 0.0352 and a coefficient of determination (R2) of 0.9984 for collapse mud weights, and an MSE of 0.0072 and an R2 of 0.9998 for fracturing mud weights on test data sets. The neural networks are statistically guaranteed to predict mud weights that are within 5% and 10% of the analytical solutions with probability up to 0.986 and 0.997, respectively, for collapse mud weights, and up to 0.9992 and 0.9998, respectively, for fracturing mud weights. Their time performances are significantly faster and less demanding in computing capacity than the analytical solution, consistently showing three-orders-of-magnitude speedups in computational speed tests. The AI solution is integrated into a deployed wellbore-stability analyzer, which is used to demonstrate the AI’s performances and advantages through three case studies.
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Kvíderová, Jana. "Sample database of the Centre for Polar Ecology - Database design and data management." Czech Polar Reports 4, no. 2 (June 1, 2014): 140–48. http://dx.doi.org/10.5817/cpr2014-2-14.
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The increasing number of observations and samples led to development of systems for data storage and management. In this paper, design and experience with data manage-ment of the Sample database (SampleDTB) used in the Centre for Polar Ecology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic, is presented. The SampleDTB was designed for microbiological, phycological or hydro-biological data. The SampleDTB consists of data tables including defined lists of cli-matic zones, habitats, communities and taxons, specific queries for datasets determina-tion and searches, forms for filling in samples and reports. The data tables contain detailed information on site, its environment, types of habitats and communities, in-cluding data on taxonomic diversity. The queries provide source data for reports or serve for searches for specific taxon, sample etc. Forms are used primarily for data entry or modifications. The reports provide summaries and charts for export, either for whole data set or for specific datasets. Data management resulted in system of sample numbering, site specification, and system for photographs storage. Possible future development will be focused on on-line data access, biovolume and diversity indices calculation, laboratory sample processing, and connection to culture collection database.
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He, Qiuwei, Siegbert Schmid, Xue Chen, Biaolin Peng, ChunChun Li, Changzheng Hu, Laijun Liu, and Manuel Hinterstein. "Structure and relaxor ferroelectric behavior of the novel tungsten bronze type ceramic Sr5BiTi3Nb7O30." Journal of Applied Physics 131, no. 16 (April 28, 2022): 164102. http://dx.doi.org/10.1063/5.0084417.
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This paper reports a novel lead-free tungsten bronze type ceramic, Sr5BiTi3Nb7O30, prepared by a conventional high-temperature solid-state reaction route. The crystal structure identified using synchrotron x-ray diffraction data and Raman spectroscopy for Sr5BiTi3Nb7O30 could be described as an average structure with the centrosymmetric space group P4/mbm and a local non-centrosymmetric structure at room temperature. In the second-harmonic generation measurement, the Sr5BiTi3Nb7O30 compound exhibits second-order nonlinear optical behavior, which suggests the material is ferroelectric. Temperature dependence of the dielectric permittivity indicates that the dielectric anomaly in Sr5BiTi3Nb7O30, associated with the disorder on the A and B sites, results in strong frequency dispersion with a low phase-transition temperature. A macroscopic and phenomenological statistical model was employed to describe the temperature dependence of the dielectric responses of Sr5BiTi3Nb7O30 and Sr6Ti2Nb8O30. The calculated sizes of polar nanoregions for both compounds imply structural disorder induced by A and B sites, giving rise to a more diffuse ferroelectric transition for Sr5BiTi3Nb7O30. The smaller polar nanoregions with smaller electrical dipole moments can be activated at lower temperatures, leading to Sr5BiTi3Nb7O30 having a lower Tm (∼260 K) than other tungsten bronze type ferroelectrics. This work charts a promising feasible route to the development of improved relaxor ferroelectrics in tungsten bronze type oxides.
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RAMABWAMY, C. "The severe drought over Tamil Nadu during the retreating monsoon period of 1968 and its associations with anomalies in the upper level flow patterns over the northern hemisphere." MAUSAM 23, no. 3 (February 3, 2022): 303–16. http://dx.doi.org/10.54302/mausam.v23i3.5282.
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The mean contours and isotherms over the Indian sub-continent at the 850.mband 300-mb levels and the moisture- content of the air over Tamil Nadu in November 1968 (a month of severe drought in that State) and in November 1966 (a month of fairly good retreating monsoon rainfall over the same area) have been discussed. The daily 700 and 500-mb charts for the Indian sub-continent, the 300 and 200-mb charts for Asia and Europe and the monthly mean 700-mb charts for the northern hemisphere during the same two months have also been studied. It has been shown that, during the drought month, the Subtropical Jet Stream System (STJS) was not only in unusually low latitudes over India but it was also markedly stronger than usual. This abnormality in the STJS was directly or indirectly associated with large-scale anomalies in the upper level flow patterns in the atmosphere over the middle and higher latitudes in the northern hemisphere. The genesis of these anomalies has been traced back step by step as far west as the United States of America.
The anomalous fluctuations of the STJS were indirectly responsible for the cyclonic storms in the Bay of Bengal being 'steered away' from Tamil Nadu and were thus also partly responsible for the drought conditions over Tamil Nadu.
The observed progressive trend of equatorward movement of the STJS along with the polar front jet and a deep cyclonic vortex in the subpolar latitudes in November 1968 has been discussed in relation to the progressive increase in the rainfall deficiency over Tamil Nadu during the Same period. It has been suggested that the parameters utilised in the present study could be tried out in medium range forecasting of rainfall over Tamil Nadu during the retreating monsoon period.
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Schröder, Wilfried, and Karl Heinrich Wiederkehr. "Synoptical weather charts of the South Atlantic and the relations between the "Deutsche Seewarte” and Argentina during the First Polar Year." Meteorologische Zeitschrift 3, no. 6 (December 23, 1994): 337–43. http://dx.doi.org/10.1127/metz/3/1994/337.
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Gasparetto, Victor E. L., and Mostafa S. A. ElSayed. "Multiscale Modelling and Mechanical Anisotropy of Periodic Cellular Solids with Rigid-Jointed Truss-Like Microscopic Architecture." Applied Mechanics 2, no. 2 (June 1, 2021): 331–55. http://dx.doi.org/10.3390/applmech2020020.
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This paper investigates the macroscopic anisotropic behavior of periodic cellular solids with rigid-jointed microscopic truss-like architecture. A theoretical matrix-based procedure is presented to calculate the homogenized stiffness and strength properties of the material which is validated experimentally. The procedure consists of four main steps, namely, (i) using classical structural analysis to determine the stiffness properties of a lattice unit cell, (ii) employing the Bloch’s theorem to generate the irreducible representation of the infinite lattice, (iii) resorting to the Cauchy–Born Hypothesis to express the microscopic nodal forces and deformations in terms of a homogeneous macroscopic strain field applied to the lattice, and (iv) employing the Hill–Mandel homogenization principle to obtain the macro-stiffness properties of the lattice topologies. The presented model is used to investigate the anisotropic mechanical behavior of 13 2D periodic cellular solids. The results are documented in three set of charts that show (i) the change of the Young and Shear moduli of the material with respect to their relative density; (ii) the contribution of the bending stiffness of microscopic cell elements to the homogenized macroscopic stiffness of the material; and (iii) polar diagrams of the change of the elastic moduli of the cellular solid in response to direction of macroscopic loading. The three set of charts can be used for design purposes in assemblies involving the honeycomb structures as it may help in selecting the best lattice topology for a given functional stiffness and strength requirement. The theoretical model was experimentally validated by means of tensile tests performed in additively manufactured Lattice Material (LM) specimens, achieving good agreement between the results. It was observed that the model of rigid-joined LM (RJLM) predicts the homogenized mechanical properties of the LM with higher accuracy compared to those predicted by pin-jointed models.
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BHOWMIK, S. K. ROY, ANUPAM KUMAR, and ANANDA K.DAS. "Real-time mesoscale modeling for short range prediction of weather over Maitri region in Antarctica." MAUSAM 62, no. 4 (December 16, 2021): 535–46. http://dx.doi.org/10.54302/mausam.v62i4.339.
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The main objective of this paper is to implement Polar WRF model for the Maitri (Lat. 70° 45 S, Long. 11° 44 E) region at the horizontal resolution of 15 km using initial and boundary conditions of the Global Forecast System T-382 operational at the India Meteorological Department (IMD). The study evaluates the performance of the model using the conventional approach of case studies. The results of the case studies illustrated in this paper reveal that the model is capable of capturing synoptic and meso-scale weather systems. Forecast fields are consistent with the corresponding analysis fields. Synoptic charts of mean sea level pressure prepared by the Weather Service of South Africa at Pretoria are used for the model validation. The model derived meteograms of mean sea level pressure are compared against the corresponding observations. The study demonstrates the usefulness of the forecast products for short range forecasting of weather over the Maitri region. The forecast outputs are made available in the real-time mode in the national web site of IMD www.imd.gov.in. The study is expected to benefit weather forecasters at Maitri.
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Andrade, Hugo Nunes, André Becker Nunes, and Rita de Cássia Marques Alves. "Analysis of the Most Intense Explosive Cyclone that Occurred Between 2010 and 2020 in the South Atlantic." Revista Brasileira de Geografia Física 15, no. 6 (2022): 2781–95. http://dx.doi.org/10.26848/rbgf.v15.6.p2781-2795.
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The coastal region of South America is known for the high frequency of extratropical cyclones. From 2010 to 2020, there was an exceptional case regarding intensity, reaching 2.73 Bergeron, between January 02 and 03, 2019. To better understand the characteristics of this type of explosive cyclone, this work sought to investigate the synoptic conditions in this phenomenon. To this end, a visual inspection method of the sea level pressure charts was applied, allied with the functions available in the Grid Analysis and Display software. The cyclone began by transitioning from the continental low to the extratropical cyclone, associated with a trough at higher levels in a zone of weak temperature advection. As the system developed, there was a fracture in the upper air trough, acquiring negative horizontal inclination and the transition of the cyclone from the tropical to the polar side of the jet streak. Sea heat fluxes become relevant only 6 hours after cyclogenesis and enhance as the surface wind increases in the cold sector of the cyclone. In addition, a robust stratospheric ozone intrusion arose close to 700 hPa in the cyclone region, related to the dynamic tropopause folding.
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Sowayan, Ahmed S., and A. Tamimi. "Comparative Prediction of Apparent Cartesian and Polar Sun Charts for Riyadh, Kingdom of Saudi Arabia = التنبؤ بمخططات الشمس الديكارتية والقطبية الظاهرة لمدينة الرياض، المملكة العربية السعودية." مجلة الشمال للعلوم الأساسية و التطبيقية 6, no. 1 (May 2021): 30–46. http://dx.doi.org/10.12816/0058336.
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Hrytsiuk, Yu I., and O. R. Ferneza. "Reflection of expert-based evaluation of software quality." Scientific Bulletin of UNFU 29, no. 8 (October 31, 2019): 152–58. http://dx.doi.org/10.36930/40290828.
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The method of reflections data, which is obtained as a result of processing expert-based evaluation of software quality by different criteria of evaluation using petal charts. Reflection of expert-based evaluation of software quality is found to be the process of reflections data in graphical form for maximum ease of understanding and rapid perception, and also providing a clear overview and shape of any object, process or phenomenon. The software quality evaluation criteria and their weighting factors for each expert are offered, which provide a reliable presentation of the current state of the software development process, a proper understanding of the problems that may arise at any stage of the program project implementation, and the exact characteristics of their components. This mechanism of data reflection enables business analysts to submit qualitatively and quantitatively multiple values of complex software quality indicators that can be obtained from the results of any survey of different experts at a particular stage of the program project implementation. The proposed methodology is suitable for presenting a variety of expert survey results, with a subdivision into unlimited number of the roles of the software quality evaluation participants concerning the importance of each of them. An algorithm for calculating the area of sectorial petals in a polar coordinate system has been developed, using which it is possible to calculate and evaluate the relative software quality according to the proper criteria. The final complex software quality indicators for each expert are determined, and a comprehensive indicator of its quality is summarized as well. An algorithm for calculating the area of a petal diagram in a polar coordinate system has been developed, which allows determining the part of software quality according to all the criteria, which is currently evaluated by one of the experts, as well as the part of software quality, which has yet to be achieved for its 100% completeness. The relevant conclusions are drawn and recommendations are made concerning the use of the developed data reflection methodology.
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Raspopov, O. M., S. N. Sokolov, I. M. Demina, R. Pellinen, and A. A. Petrova. "The first aeromagnetic survey in the Arctic: results of the Graf Zeppelin airship flight of 1931." History of Geo- and Space Sciences 4, no. 1 (March 13, 2013): 35–46. http://dx.doi.org/10.5194/hgss-4-35-2013.
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Abstract. In July of 1931, on the eve of International Polar Year II, an Arctic flight of the Graf Zeppelin rigid airship was organized. This flight was a realization of the idea of F. Nansen, who advocated the use of airships for the scientific exploration of the Arctic territories, which were poorly studied and hardly accessible at that time. The route of the airship flight was Berlin – Leningrad – Arkhangelsk – Franz Josef Land – Severnaya Zemlya – the Taimyr Peninsula – Novaya Zemlya – Arkhangelsk – Berlin. One of scientific goals of the expedition was to measure the H and D geomagnetic field components. Actually, the first aeromagnetic survey was carried out in the Arctic during the flight. After the expedition, only preliminary results of the geomagnetic measurements, in which an anomalous behavior of magnetic declination in the high-latitude part of the route was noted, were published. Our paper is concerned with the first aeromagnetic measurements in the Arctic and their analysis based on archival and modern data on the magnetic field in the Barents and Kara sea regions. It is shown that the magnetic field along the flight route had a complicated structure, which was not reflected in the magnetic charts of those times. The flight was very important for future development of aero- and ground-based magnetic surveys in the Arctic, showing new methods in such surveys.
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SoltanRezaee, Masoud, Mohammad-Reza Ghazavi, and Asghar Najafi. "Parametric resonances for torsional vibration of excited rotating machineries with nonconstant velocity joints." Journal of Vibration and Control 24, no. 15 (April 12, 2017): 3262–77. http://dx.doi.org/10.1177/1077546317703542.
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The shaft system is a rotating machinery with many applications due to its high speed. The angle between shafts may not be zero. So the shafts can be connected to each other through a nonconstant velocity U-joint, which transforms a constant input angular velocity into a periodically fluctuating velocity. Consequently, the mechanism is parametrically excited and may face resonance conditions. Herein, a power transmission system including three elastic shafts is considered. The polar inertia moment of each shaft is modeled as a dynamic system with two discrete disks at the shaft ends. The equations of motion consist of a set of Mathieu–Hill differential equations with periodic coefficients. The dynamic stability and torsional vibration of the shaft system are analyzed. The system geometry and inertia moment effect are the main issues in this contribution. Parametric instability charts are achieved via the monodromy matrix technique. The graphical numerical results are validated with the frequency analytical results. Finally, the stability regions are shown in the parameter spaces of velocity, misalignment angles and the inertia of disks. The results demonstrated that by changing the system inertia and geometry, stabilizing the whole system is possible. Moreover, to check the precision of the model, the results are compared with a basic single-disk model, which is prevalent in two-shaft systems.
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Melsheimer, Christian, Gunnar Spreen, Yufang Ye, and Mohammed Shokr. "First results of Antarctic sea ice type retrieval from active and passive microwave remote sensing data." Cryosphere 17, no. 1 (January 12, 2023): 105–26. http://dx.doi.org/10.5194/tc-17-105-2023.
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Abstract. Polar sea ice is one of the Earth's climate components that has been significantly affected by the recent trend of global warming. While the sea ice area in the Arctic has been decreasing at a rate of about 4 % per decade, the multi-year ice (MYI), also called perennial ice, is decreasing at a faster rate of 10 %–15 % per decade. On the other hand, the sea ice area in the Antarctic region was slowly increasing at a rate of about 1.5 % per decade until 2014, and since then it has fluctuated without a clear trend. However, no data about ice type areas are available from that region, particularly for MYI. Due to differences in the physical and crystalline structural properties of sea ice and snow between the two polar regions, it has become difficult to identify ice types in the Antarctic. Until recently,no satellite retrieval scheme was ready to monitor the distribution and temporal development of Antarctic ice types, particularly MYI, throughout the freezing season and on timescales of several years. In this study, we have adapted a method for retrieving Arctic sea ice types and partial concentrations using microwave satellite observations to fit the Antarctic sea ice conditions. The core of the retrieval method is a mathematical scheme that needs empirical distributions of the microwave brightness temperature and backscatter input parameters for the different ice types. The first circumpolar, long-term time series of Antarctic sea ice types (MYI, first-year ice, and young ice) is being established, and so far covers the years 2013–2021. Qualitative comparison with (a) synthetic aperture radar data, (b) charts of the development stage of the sea ice, and (c) the Antarctic polynya distribution data show that the retrieved ice types, in particular the MYI, are reasonable. Although there are still some shortcomings, the new retrieval allows insight into the interannual evolution and dynamics of Antarctic sea ice types for the first time. The current time series can in principle be extended backwards to start in the year 2002 and can be continued with current and future sensors.
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Sha, Dexuan, Xin Miao, Mengchao Xu, Chaowei Yang, Hongjie Xie, Alberto M. Mestas-Nuñez, Yun Li, Qian Liu, and Jingchao Yang. "An On-Demand Service for Managing and Analyzing Arctic Sea Ice High Spatial Resolution Imagery." Data 5, no. 2 (April 17, 2020): 39. http://dx.doi.org/10.3390/data5020039.
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Sea ice acts as both an indicator and an amplifier of climate change. High spatial resolution (HSR) imagery is an important data source in Arctic sea ice research for extracting sea ice physical parameters, and calibrating/validating climate models. HSR images are difficult to process and manage due to their large data volume, heterogeneous data sources, and complex spatiotemporal distributions. In this paper, an Arctic Cyberinfrastructure (ArcCI) module is developed that allows a reliable and efficient on-demand image batch processing on the web. For this module, available associated datasets are collected and presented through an open data portal. The ArcCI module offers an architecture based on cloud computing and big data components for HSR sea ice images, including functionalities of (1) data acquisition through File Transfer Protocol (FTP) transfer, front-end uploading, and physical transfer; (2) data storage based on Hadoop distributed file system and matured operational relational database; (3) distributed image processing including object-based image classification and parameter extraction of sea ice features; (4) 3D visualization of dynamic spatiotemporal distribution of extracted parameters with flexible statistical charts. Arctic researchers can search and find arctic sea ice HSR image and relevant metadata in the open data portal, obtain extracted ice parameters, and conduct visual analytics interactively. Users with large number of images can leverage the service to process their image in high performance manner on cloud, and manage, analyze results in one place. The ArcCI module will assist domain scientists on investigating polar sea ice, and can be easily transferred to other HSR image processing research projects.
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Boardman, Diane, David Darwin, Jolyon Martin, Neil Mclntyre, and Ken Sullivan. "Development of a sea-ice workstation for the automated monitoring of sea ice." Polar Record 31, no. 177 (April 1995): 155–60. http://dx.doi.org/10.1017/s0032247400013656.
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AbstractUK-based operations that range from ship routing and resource exploration to weather forecasting and glaciology have direct and growing interests in the oceans of the polar regions. Typically, information describing sea-ice conditions in localised regions is required on short time scales. To explore this market, the UK's Defence Research Agency, as part of a programme of the British National Space Centre, has commissioned the development of a prototype sea-ice workstation by a consortium led by Earth Observation Sciences Ltd.The sea-ice workstation (SIWS) uses data from several current earth observation sensors, thereby combining the advantages of regional survey, all-weather capability, and high-resolution imagery. The workstation has been designed to run with a minimum of operator intervention in order to optimise speed of operation and ensure consistency of results. The geophysical processing chains generate charts of the ice edge, ice type, ice concentration, ice-motion vectors, and sea-surface temperatures.Although taking full advantage of developments made elsewhere, the project has also made significant progress in research into the automated mapping of ice types. Existing ice-motion algorithms have been significantly enhanced as well. Considerable emphasis is being placed on the validation of the results from the system in order to assess their quality, this being one of the major concerns of potential users. The sea-ice workstation was completed in July 1994 and will form the basis for a series of evaluations that are intended to assess the value of the system for mapping and monitoring sea ice.
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Brunette, Charles, Bruno Tremblay, and Robert Newton. "Winter Coastal Divergence as a Predictor for the Minimum Sea Ice Extent in the Laptev Sea." Journal of Climate 32, no. 4 (February 2019): 1063–80. http://dx.doi.org/10.1175/jcli-d-18-0169.1.
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Seasonal predictability of the minimum sea ice extent (SIE) in the Laptev Sea is investigated using winter coastal divergence as a predictor. From February to May, the new ice forming in wind-driven coastal polynyas grows to a thickness approximately equal to the climatological thickness loss due to summer thermodynamic processes. Estimating the area of sea ice that is preconditioned to melt enables seasonal predictability of the minimum SIE. Wintertime ice motion is quantified by seeding passive tracers along the coastlines and advecting them with the Lagrangian Ice Tracking System (LITS) forced with sea ice drifts from the Polar Pathfinder dataset for years 1992–2016. LITS-derived landfast ice estimates are comparable to those of the Russian Arctic and Antarctic Research Institute ice charts. Time series of the minimum SIE and coastal divergence show trends of −24.2% and +31.3% per decade, respectively. Statistically significant correlation ( r = −0.63) between anomalies of coastal divergence and the following September SIE occurs for coastal divergence integrated from February to the beginning of May. Using the coastal divergence anomaly to predict the minimum SIE departure from the trend improves the explained variance by 21% compared to hindcasts based on persistence of the linear trend. Coastal divergence anomalies correlate with the winter mean Arctic Oscillation index ( r = 0.69). LITS-derived areas of coastal divergence tend to underestimate the total area covered by thin ice in the CryoSat-2/SMOS (Soil Moisture and Ocean Salinity) thickness dataset, as suggested by a thermodynamic sea ice growth model.
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Nascimento, Diego, Luan Victor Lima, and Vitor Cruz. "Episódios e gênese dos eventos climáticos extremos em Goiânia-GO / Episodes and genesis of extreme climate events in Goiânia-GO." Caderno de Geografia 29, no. 57 (April 25, 2019): 583–608. http://dx.doi.org/10.5752/p.2318-2962.2019v29n57p583-608.
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Sob a abordagem da climatologia geográfica, que leva em consideração a dinâmica das massas de ar na análise do ritmo e da gênese do clima, o presente trabalho busca apresentar os episódios de eventos climáticos extremos ocorridos em Goiânia-GO e abordar os mecanismos atmosféricos responsáveis pela gênese dos mesmos. Os eventos extremos foram levantados a partir de dados diários precipitação, temperatura máxima e mínima e umidade relativa do ar, registrados pela estação meteorológica do Instituto Nacional de Meteorologia (INMET), compreendendo a série temporal de 1961 a 2018 (58 anos). A identificação dos mecanismos atmosféricos atuantes nos dias dos episódios extremos foi realizada a partir da leitura e interpretação de cartas sinóticas da Marinha do Brasil, tendo como base o recorte temporal de 2012 a 2018. Foi possível apontar a ocorrência de eventos extremos em períodos específicos do ano, como no caso de eventos de precipitação no verão, sob influência da Massa equatorial continental e da Zona de Convergência do Atlântico Sul; de temperatura máxima no final do inverno e início da primavera, quando predomina a Massa equatorial continental e a Massa tropical Atlântica; de temperatura mínima no outono e inverno, condicionados pela incursão da Massa polar; de umidade relativa do ar no inverno, ocorrendo devido a atuação dos sistemas atmosféricos que habitualmente definem a condição sinótica em Goiânia.Palavras–chave: eventos extremos, massas de ar, fatores, mecanismos, impactos.Abstract Under the approach of Geographical Climatology, which takes into account the dynamics of the air masses in the analysis of the rhythm and the genesis of the climate, the present work seeks to present the episodes of extreme climatic events occurring in Goiânia-GO and to indicate the atmospheric mechanisms responsible for the genesis of this events. The extreme events were listed from daily precipitation, maximum and minimum temperature and relative humidity data, recorded by the meteorological station of the National Institute of Meteorology, comprising the time series from 1961 to 2018 (58 years). The identification of the atmospheric mechanisms acting on the days of the extreme episodes was performed from the reading and interpretation of Brazilian Navy's synoptic charts, based on the temporal cut from 2012 to 2018. It was possible to indicate the occurrence of extreme events in specific periods of the year, as in the case of summer precipitation events, under the influence of Continental equatorial mass and South Atlantic Convergence Zone; of maximum temperature in late winter and early spring, when Continental equatorial mass and Atlantic tropical mass predominate; of minimum temperature in autumn and winter, conditioned by the incursion of Polar mass; of relative humidity of the air in the winter, occurring due to the performance of the atmospheric systems that habitually define the synoptic condition in Goiânia.Keywords: extreme events, air masses, factors, mechanisms, impacts
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Cao, Changyong, Mitch Goldberg, and Likun Wang. "Spectral Bias Estimation of Historical HIRS Using IASI Observations for Improved Fundamental Climate Data Records." Journal of Atmospheric and Oceanic Technology 26, no. 7 (July 1, 2009): 1378–87. http://dx.doi.org/10.1175/2009jtecha1235.1.
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Abstract A prerequisite for climate change detection from satellites is that the measurements from a series of historical satellites must be consistent and ideally made traceable to the International System of Units (SI). Unfortunately, this requirement is not met for the 14 High Resolution Infrared Radiation Sounders (HIRS) on the historical NOAA satellites, because the instrument was developed for weather forecasts and lacks accuracy and consistency across satellites. It is well known that for HIRS, differences in the spectral response functions (SRF) between instruments and their prelaunch measurement uncertainties often lead to observations of the atmosphere at different altitudes. As a result of the atmospheric lapse rate, they both can introduce significant intersatellite biases. The SRF-dependent biases are further mixed with other effects such as the diurnal cycle because of observation time differences and orbital drifts, on board calibration, and algorithm issues. In this study, the Infrared Atmospheric Sounding Interferometer (IASI) observations are used to calculate the radiances for the 14 Television Infrared Observation Satellite series N (TIROS-N; to MetOp-A) HIRS instruments in different climate regimes and seasons to separate the SRF-induced intersatellite biases from other factors. It is found that the calculated radiance ratio (a bias indicator) using IASI observations for the HIRS satellite pairs forms bell-shaped curves that vary with the HIRS model and channel as well as climate regimes. This suggests that a bias found in the polar regions at the Simultaneous Nadir Overpass (SNO) cannot be blindly used for bias correction globally; instead, the IASI/HIRS spectral bias bell curves should be used as a complement to more fully address the biases. These bell curves also serve as lookup charts for separating the bias due to true SRF differences from that caused by SRF prelaunch measurement errors to resolve the inconsistency, which sheds new light on reprocessing and reanalysis in generating fundamental climate data records from HIRS.
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Bojkov, R. D., and D. S. Balis. "Characteristics of episodes with extremely low ozone values in the northern middle latitudes 1957−2000." Annales Geophysicae 19, no. 7 (July 31, 2001): 797–807. http://dx.doi.org/10.5194/angeo-19-797-2001.
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Abstract. A number of episodes are observed when the total ozone for 2 to 3 days has fallen below 220 matm-cm in the northern mid- and polar latitudes in autumn. The occurrences of such episodes represent ozone deviations of about one-third from the pre-1976 Oct-Nov-Dec monthly mean! By using primarily quality checked Dobson data, a clear identification was made of more than three dozen short spells with extremely low ozone in the 1957–1978 period. In the following twenty-two years (1979–2000), using mainly TOMS data, one can identify ~ 46 cases with ozone values falling below 220 matm-cm for longer than 1 day, with each time over an area greater than 500,000 km2 . The Ozone Mass Deficiency (O3MD) from the pre-1976 average ozone values over the affected area was ~2.8 Mt per day, i.e. four to seven times greater than it would be, assuming only a long-term trend in the Oct-Nov-Dec period. The Extremely Low Ozone (ELO3) events on the day of their appearance over the N. Atlantic/European region contribute to the O3MD by representing 16% of the deficiency due to the Oct-Nov trend in the entire 40–65° N latitudinal belt. The O3MD of the greater pool with low ozone (here taken as <260 matm-cm) surrounding the area of the lowest events could contribute on the day of their appearance in Oct-Nov up to 60% and in December, ~30% to the deficiency due to the trend over the entire 40–65° N belt. Analysis of synoptic charts, supported by a backward trajectory on the isentropic surfaces 350 and 380 K, shows that in most of the events, subtropical air masses with low ozone content were transported from the Atlantic toward the UK, Scandinavia, and in many cases, further to the western sub-polar regions of Russia. This transport was sometimes combined with upward motions above a tropospheric anticyclone which lifted low ozone mixing ratios to higher altitudes. The ELO3 events cause a significant deficiency above the tropopause where, in general, the subtropical air is injected. In fact, the overall amount of ozone is not depleted, but redistributed on the hemispheric scale. Review of low ozone events, defined as days with negative deviations from the pre-1976 averages greater than 25% show, in general, similar origin. The seasonally averaged area with ELO3 and the associated O3MD, as well as for the cases with deviations > –25%, has increased during the 1990s, which could be an indication of stronger and/or more frequent subtropical air intrusions. Their occurrences could contribute noticeably to the ozone deficiency of the middle latitude ozone during the days of ELO3 appearances; however, their contribution to the long-term trend of the ozone seasonal decline is of the order of ~10%.Key words. Atmospheric composition and structure (middle atmosphere - composition and chemistry) Meteorology and atmospheric dynamics (middle atmosphere dynamics)
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Chernokulsky, Alexander, Andrey Shikhov, Alexey Bykov, and Igor Azhigov. "Satellite-Based Study and Numerical Forecasting of Two Tornado Outbreaks in the Ural Region in June 2017." Atmosphere 11, no. 11 (October 22, 2020): 1146. http://dx.doi.org/10.3390/atmos11111146.
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Strong tornadoes are common for the European part of Russia but happen rather rare east of the Urals. June 2017 became an exceptional month when two tornado outbreaks occurred in the Ural region of Russia, yielded $3 million damage, and resulted in 1 fatality and 14 injuries. In this study, we performed detailed analysis of these outbreaks with different data. Tornadoes and tornado-related environments were diagnosed with news and eyewitness reports, ground-based meteorological observations, sounding data, global numerical weather prediction (NWP) models data, synoptic charts, satellite images, and data of specially conducted aerial imaging. We also estimated the accuracy of short-term forecasting of outbreaks with the WRF-ARW mesoscale atmospheric model, which was run in convection-permitting mode. We determined the formation of 28 tornadoes during the first outbreak (3 June 2017) and 9 tornadoes during the second outbreak (18 June 2017). We estimated their intensity using three different approaches and confirmed that, based on the International Fujita scale (IF), one of the tornadoes had the IF4 intensity, being the first IF4 tornado in Russia in the 21st century and the first-ever IF4 tornado reported beyond the Ural Mountains. The synoptic-scale analysis revealed the similarity of two outbreaks, which both formed near the polar front in the warm part of deepening southern cyclones. Such synoptic conditions yield mostly weak tornadoes in European Russia; however, our analysis indicates that these conditions are likely favorable for strong tornadoes over the Ural region. Meso-scale analysis indicates that the environments were favorable for tornado formation in both cases, and most severe-weather indicators exceeded their critical values. Our analysis demonstrates that for the Ural region, like for other regions of the world, combined use of the global NWP model outputs indicating high values of severe-weather indices and the WRF model forecast outputs explicitly simulating tornadic storm formation could be used to predict the high probability of strong tornado formation. For both analyzed events, the availability of such tornado warning forecast could help local authorities to take early actions on population protection.
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Li, Hui Jun, Zhi Quan Li, Jing Xuan Peng, and Li Hui Zhang. "Research on Interactive Visualization Clustering Method Based on the Radar Chart." Applied Mechanics and Materials 241-244 (December 2012): 1633–39. http://dx.doi.org/10.4028/www.scientific.net/amm.241-244.1633.
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Most algorithms for the high-dimensional data clustering are not intuitive and the clustering results are difficult to explain. To solve these problems, a new method based on the interactive visualization technology was proposed in this paper. First, the entropy-weight was adopted to determine the main attributes and how to arrange them. Every data was described in an improved radar chart in which polar radius stood by attribute values and polar angles stood by the attribute weights. Then the points in the radar chart were clustered through applying an improved k-means algorithm. The number of clusters was not given before. And initial centers were optimized according to the point density and their distance. Finally, the experiment showed that the improved radar chart reflected the distribution of the data better and that the improved k-means algorithm was more efficient and accuracy.
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Liu, Zhenzhen, Kai Niu, Chao Dong, and Jiaru Lin. "Adding a Rate-1 Third Dimension to Parallel Concatenated Systematic Polar Code: 3D Polar Code." Wireless Communications and Mobile Computing 2018 (2018): 1–6. http://dx.doi.org/10.1155/2018/8928761.
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In this paper, a three-dimensional polar code (3D-PC) scheme is proposed to improve the error floor performance of parallel concatenated systematic polar code (PCSPC). The proposed 3D-PC is constructed by serially concatenating the PCSPC with a rate-1 third dimension, where only a fraction λ of parity bits of PCSPC are extracted to participate in the subsequent encoding. It takes full advantage of the characteristics of parallel concatenation and serial concatenation. In addition, the convergence behavior of 3D-PC is analyzed by the extrinsic information transfer (EXIT) chart. The convergence loss between PCSPC λ=0 and different λ provides the reference for choosing the value of λ for 3D-PC. Finally, the simulation results confirm that the proposed 3D-PC scheme lowers the error floor.
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Adeel, Arooj, Muhammad Akram, and Ali N. A. Koam. "Group Decision-Making Based on m-Polar Fuzzy Linguistic TOPSIS Method." Symmetry 11, no. 6 (May 29, 2019): 735. http://dx.doi.org/10.3390/sym11060735.
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The fuzzy linguistic approach provides favorable outputs in several areas, whose description is relatively qualitative. The encouragement for the utilization of sentences or words instead of numbers is that linguistic characterizations or classifications are usually less absolute than algebraic or arithmetical ones. In this research article, we animate the m-polar fuzzy (mF) linguistic approach and elaborate it with real life examples and tabular representation to develop the affluence of linguistic variables based on mF approach. As an extension of the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method, we develop an m-polar fuzzy linguistic TOPSIS approach for multi-criteria group decision-making (MCGDM). It is used to evaluate the best alternative, to get more authentic and comparable results and to handle the real life problems of having multi-polar information in terms of linguistic variables and values. In this approach decision-makers contribute their estimations in the form of linguistic term sets. To show the efficiency and compatibility of the proposed approach, we compare it with the m-polar fuzzy linguistic ELECTRE-I (Elimination and Choice Translating Reality) approach. Finally, we draw a flow chart of our proposed approach as an algorithm and generate a computer programming code.
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Akram, Muhammad, Maheen Sultan, and Ahmad N. Al-Kenani. "Group Decision Analysis Based on Complex m-Polar Fuzzy N-Soft Environment." Mathematical Problems in Engineering 2022 (April 26, 2022): 1–24. http://dx.doi.org/10.1155/2022/4917408.
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This research article presents a novel multicriteria group decision-making (MCGDM) technique, namely, complex m-polar fuzzy N-soft TOPSIS (CmPFNS-TOPSIS), that incorporates the remarkable features of manipulating the complex two-dimensional data and the multipolarity of the modern era with the help of CmPFNSS and the multicriteria group decision making potential of the TOPSIS technique. This newly proposed technique shares a very general parametric structure of the CmPFMSS and enables us to make the suitable decisions in this multipolar complex two-dimensional domain. The incredible CmPFNS-TOPSIS technique works on the principle of finding the optimal solution nearest to the positive ideal solution (PSS) and farthest from the negative ideal solution (NIS) by evaluating the Euclidean distance between the alternatives and the optimal solutions. The support of complex m-polar fuzzy N-soft weighted averaging operator (CmPFNSWA), Euclidean distance, score function, and the revised closeness index is utilized for uncovering our optimal solutions. The alternatives, with respect to the revised closeness index, are arranged in the descending order and the alternative with the least closeness index is preferred. The methodology of the CmPFNS-TOPSIS technique is illustrated with the help of the flow chart. The proficiency of this technique is proved by considering a case study of selection of the suitable surgical equipment in the oncology department of Shaukat Khanum Hospital, Lahore (Pakistan). To prove its validity and credibility, a comparative analysis between CmPFNS-TOPSIS and m-polar fuzzy N-soft TOPSIS (mFNS-TOPSIS) is pictured with the help of a bar chart displaying the same end results of the CmPFNS-TOPSIS and mFNS-TOPSIS.
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Akram, Muhammad, Maheen Sultan, and Ahmad N. Al-Kenani. "Group Decision Analysis Based on Complex m-Polar Fuzzy N-Soft Environment." Mathematical Problems in Engineering 2022 (April 26, 2022): 1–24. http://dx.doi.org/10.1155/2022/4917408.
Full textAbstract:
This research article presents a novel multicriteria group decision-making (MCGDM) technique, namely, complex m-polar fuzzy N-soft TOPSIS (CmPFNS-TOPSIS), that incorporates the remarkable features of manipulating the complex two-dimensional data and the multipolarity of the modern era with the help of CmPFNSS and the multicriteria group decision making potential of the TOPSIS technique. This newly proposed technique shares a very general parametric structure of the CmPFMSS and enables us to make the suitable decisions in this multipolar complex two-dimensional domain. The incredible CmPFNS-TOPSIS technique works on the principle of finding the optimal solution nearest to the positive ideal solution (PSS) and farthest from the negative ideal solution (NIS) by evaluating the Euclidean distance between the alternatives and the optimal solutions. The support of complex m-polar fuzzy N-soft weighted averaging operator (CmPFNSWA), Euclidean distance, score function, and the revised closeness index is utilized for uncovering our optimal solutions. The alternatives, with respect to the revised closeness index, are arranged in the descending order and the alternative with the least closeness index is preferred. The methodology of the CmPFNS-TOPSIS technique is illustrated with the help of the flow chart. The proficiency of this technique is proved by considering a case study of selection of the suitable surgical equipment in the oncology department of Shaukat Khanum Hospital, Lahore (Pakistan). To prove its validity and credibility, a comparative analysis between CmPFNS-TOPSIS and m-polar fuzzy N-soft TOPSIS (mFNS-TOPSIS) is pictured with the help of a bar chart displaying the same end results of the CmPFNS-TOPSIS and mFNS-TOPSIS.
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Dong, Yanfei, and Kai Niu. "Double Polar Codes for Joint Source and Channel Coding." Electronics 11, no. 21 (October 31, 2022): 3557. http://dx.doi.org/10.3390/electronics11213557.
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In this paper, we design a joint source and channel coding (JSCC) framework combining the source polar coding and the channel polar coding. The source is first compressed using a polar code (PC), and source check decoding is employed to construct an error set containing the index of all source decoding errors. Then, the proposed JSCC system employs another PC or systematic PC (SPC) to protect the compressed source and the error set against noise, which is called double PC (D-PC) or systematic double PC (SD-PC), respectively. For a D-PC JSCC system, we prove a necessary condition for the optimal mapping between the source PC and the channel PC. On the receiver side, by introducing the joint factor graph representation of the D-PC and SD-PC, we propose two joint source and channel decoders: a joint belief propagation (J-BP) decoder, and a systematic joint belief propagation (SJ-BP) decoder. In addition, a biased extrinsic information transfer (B-EXIT) chart is developed for various decoders as a theoretical performance evaluation tool. Both B-EXIT and simulation results show that the performance of the proposed JSCC scheme has no error floor and outperforms the turbo-like BP decoder.
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Bulkeley, Rip. "Bellingshausen’s “Mountains”: The 1820 Russian sighting of Antarctica and Bellingshausen’s theory of the South Polar ice cap." Polar Record 55, no. 6 (November 2019): 392–401. http://dx.doi.org/10.1017/s0032247419000755.
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AbstractThere has been some uncertainty as to which of the two southerly probes, during which Bellingshausen passed latitude 69°S in early 1820, achieved the first sighting of an ice coast of Dronning Maud Land in Eastern Antarctica. The author criticizes Frank Debenham’s English translation of Bellingshausen’s narrative before presenting and discussing new translations of Bellingshausen’s descriptions of those events, with relevant sections of his track chart, plus a third passage from the book which interpreted what was seen. He concludes that the Russians first sighted an ice coast in mid-February, rather than late January as has been widely claimed.
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Babiker, Omer Eisa, Mahadzir Shuhaimi, and Mohammed Ibrahim Abdul Mutalib. "Molecular Simulation for Piperazinium Based ILs: Effects of Alkyl Chain, Concentration and Anions on Henry’s Constants." Applied Mechanics and Materials 625 (September 2014): 448–53. http://dx.doi.org/10.4028/www.scientific.net/amm.625.448.
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a simulation study of molecule structuring, electrons density polarization (σ-profile) and Henry’s law constant (HLC) have been achieved for three of the dual charge cation ionic liquids (DCCILs) specifically, 1, 4-di-(butyl, hexyl, Octyl)-1, 4-dimethyl-piperazinium using COSMO-RS molecular dynamic software. The electron density chart indicates the ability of the DCCILs to interact with the polar groups (H-bond donor) which was presented the strong peak in (-1.2×10-2) e/Ǻ2. The DCCILs also showed a strong peaks to interact with the non-polar groups which are located at (-0.2×10-2) e/Ǻ2). The screening of the selected anions showed a significant deferens in predicted Henry’s constant values. The BF4-anion presented the greatest HLC values followed by NO3-, Br-PF6-and finally the [octylsulfate]-as lowest HLC values. The increases of DCCILs concentration always use to decrease the HLC values for all presented anions. The outcomes of this work were systematically pointed to the possibility of DCCILS solubility in water. In addition the study identified and classified the selected anions and the cation alkyl chain in terms of their contribution to improve the CO2solubility in DCCILs.
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Mohsin, Hazim D. "Using the Polar Jet Stream Core Wind Speed to Estimate the Surface Low Pressure System value during winter." Al-Mustansiriyah Journal of Science 30, no. 1 (August 15, 2019): 7. http://dx.doi.org/10.23851/mjs.v30i1.448.
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The work studied the relationship between polar jet stream core speed at 300 hPa level and the surface low pressure system on winter seasons during years from 2014 to 2016. Februaries were chosen from winter seasons which the polar jet stream passes with high frequencies over the area of study. The study presented that the structure of polar jet was almost continuous jet-type structure that the jet core was easy to recognize and it had indirect relationship with the low pressure systems at surface. the Pearson's (R) statistical test used to show the strength of that relationship which accessible values were between (0.6 - 1) that presented the core speed values as a good element to derive equation connecting between the low pressure system value in (hPa) at surface and core speed value in (kt) at 300 hPa level . The simple linear regression technique is used to drive the equation that connects between the low pressure system and the jet core speed value which was (Low pressure center value (hPa) =1042.57 ̶ (0.307 × core speed (kt) )) . The equation was tested against some jet stream cases at 300 hPa that were the highest value of the jet core speed, the lowest and middle selected value which presented the percentage errors were between (0.03-0.09). the chart analyzing presented the lowest low pressure system center corresponded the highest the jet core speed values as shown in 11 Feb., 2015 at 00 UTC which the core speed was 150 (kt) corresponding the surface low pressure system which was 993 (hPa)
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Adeel, Arooj, Muhammad Akram, Imran Ahmed, and Kashif Nazar. "Novel m-Polar Fuzzy Linguistic ELECTRE-I Method for Group Decision-Making." Symmetry 11, no. 4 (April 2, 2019): 471. http://dx.doi.org/10.3390/sym11040471.
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Linguistic variables play a vital role in several qualitative decision environments, in which decision-makers assume several feasible linguistic values or criteria instead of a single term for an alternative or variable. The motivation for the use of words or sentences instead of numbers is that linguistic classification and characterizations are generally less precise than numerical ones. In this research article, we encourage the fuzzy linguistic approach and introduce the novel concept known as m-polar fuzzy linguistic variable (mFLV) to increase the affluence of linguistic variables based on m-polar fuzzy (mF) approach. An mF set is an effective concept for interpreting uncertainty and fuzziness. The concept of mFLV is more versatile and sensible for dealing with real-life problems, when data comes from qualitative and multipolar information. We also introduce an mF linguistic ELECTRE-I approach to solve multiple-criteria decision-making (MCDM) and multiple-criteria group decision-making (MCGDM) problems, where the evaluation of the alternatives under suitable linguistic values are determined by the decision-makers. Furthermore, we validate the efficiency of our proposed technique by applying it to real-life examples, such as the salary analysis of companies and by selecting a corrupt country. Finally, we develop an algorithm of our proposed approach, present its flow chart, and generate computer programming code.
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Andrienko, Gennady, and Natalia Andrienko. "Creating Maps of Artificial Spaces for Exploring Trajectories." Abstracts of the ICA 1 (July 15, 2019): 1–2. http://dx.doi.org/10.5194/ica-abs-1-9-2019.
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<p><strong>Abstract.</strong> We propose an approach to interactive visual exploration of trajectories of moving objects in which trajectories are mapped onto different coordinate systems enabling the analyst to look at different aspects of the movement. Geographic visualization techniques can be applied to these coordinate systems in the same way as in usual geographic maps. Movement, i.e., changes of spatial positions of discrete objects, is a complex phenomenon comprising many aspects [1].</p><p>Maps showing the object tracks in space are essential for analysing movement in relation to the spatial context. However, maps alone are insufficient for representing various dynamic attributes of the movement, and they are usually combined with other types of visual displays. The most commonly used display type is the time graph, i.e., a line chart with one dimension representing time and the other dimension used for encoding attribute values. There are examples of similar displays where time is substituted by a relative distance along a path. This idea can be generalized so that two display dimensions represent any two dynamic attributes, which is the basis of our approach.</p><p>Data describing movements of discrete objects consist of records that include time stamps and spatial positions (coordinates) of the objects at the specified times. Such data are commonly called trajectories. Trajectory records may also include values of dynamic attributes characterizing the movement of the moving objects, such as speed or heart rate, and they can be extended with values of various attributes derivable from the positions and times. Trajectories are typically represented in a map by lines connecting spatial positions of objects in the chronological order. This is analogous to representing trajectories in a line chart by connecting positions corresponding to attribute values at different times. Our idea is to treat such line charts as maps representing artificial spaces. This gives us an opportunity to use a uniform set of visualization and interaction techniques for map displays based on both physical and artificial spaces. To create an artificial space and a corresponding map, the analyst selects two attributes that will form the space dimensions. The analyst may choose to build either a Cartesian or a polar coordinate system. Depending on the value ranges of the attributes, the analyst may set a scaling factor for one of the dimensions. The analyst may also create a map layer with labelled axes or grid lines corresponding to specified attribute values. Examples of maps of artificial spaces are given in Fig. 2 and Fig. 3. They are based on a set of 5,045 trajectories of flights that arrived to the airports of London in the period December 1-4, 2016. Fig. 1 shows these trajectories in the geographic space. One selected trajectory is marked in black in all displays in Figs. 1-3.</p><p>Fig. 1 demonstrates usual map displays, in which cartographic visualization techniques are used to represent attribute values associated with trajectories or their segments. On the left, the colouring of the lines encodes the landing directions, from which the eastern (green) and western (purple) ones notably prevail. On the right, colouring is applied to segments of the trajectories, so that red represents holding loops [2], when pilots wait for a permission to land. Figs. 2-3 demonstrate the use of the same visualization techniques in maps based on artificial spaces. In Fig. 2, the lines arecoloured according to the landing directions, and we can see that the western landing direction was used till themorning of the second day and then gave way to the eastern direction. In Fig. 3, red and blue colours discriminate theholding loops from the remaining parts of the flights.</p><p>We see (top left of Fig.3) that the loops are especially frequent in the times from about 8 till about 17:30 o’clock, which corresponds to high frequency of arrivals in these times. We see (top right and bottom left) two major ranges of the distance to the destination in which the loops take place, and we see (bottom left and right) the range of altitudes at which the loops are made. These displays also show us that the airplanes descend stepwise, and the altitude decreases when they make loops.</p><p>Map displays based on artificial spaces allow the same interactive operations as usual map displays: zooming, panning, switching on and off the drawing of map layers, changing the appearances of objects in the layers (colour, line thickness, transparency, etc.), interactive selection of objects, which become marked in all currently existing displays (see an example in Figs. 1-3). All maps are responsive to interactive filtering, which may involve various types of query conditions [1]: spatial, temporal, and thematic, i.e., based on attribute values. Moreover, a spatial filter can be interactively set directly in a map display, e.g., by drawing one or more “windows” selecting regions in space. The same can be done in maps based on artificial spaces. Such a filter selects objects based on the values of the attributes represented by the space dimensions. All kinds of filtering affect all currently existing displays, which are coordinated in this way.</p><p>We conclude that map displays employing cartographic visualization techniques for representing data can be based not only on the geographical space, but also on various artificial spaces. The latter can be created from attributes present in or derived from the data. Maps based on such spaces support exploration of various aspects of the data.</p>
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Taylor, Graham K., Kate V. Reynolds, and Adrian L. R. Thomas. "Soaring energetics and glide performance in a moving atmosphere." Philosophical Transactions of the Royal Society B: Biological Sciences 371, no. 1704 (September 26, 2016): 20150398. http://dx.doi.org/10.1098/rstb.2015.0398.
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Here, we analyse the energetics, performance and optimization of flight in a moving atmosphere. We begin by deriving a succinct expression describing all of the mechanical energy flows associated with gliding, dynamic soaring and thermal soaring, which we use to explore the optimization of gliding in an arbitrary wind. We use this optimization to revisit the classical theory of the glide polar, which we expand upon in two significant ways. First, we compare the predictions of the glide polar for different species under the various published models. Second, we derive a glide optimization chart that maps every combination of headwind and updraft speed to the unique combination of airspeed and inertial sink rate at which the aerodynamic cost of transport is expected to be minimized. With these theoretical tools in hand, we test their predictions using empirical data collected from a captive steppe eagle ( Aquila nipalensis ) carrying an inertial measurement unit, global positioning system, barometer and pitot tube. We show that the bird adjusts airspeed in relation to headwind speed as expected if it were seeking to minimize its aerodynamic cost of transport, but find only weak evidence to suggest that it adjusts airspeed similarly in response to updrafts during straight and interthermal glides. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’.
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Lian, Fei, Fang Huang, Wei Chen, Baoshan Xing, and Lingyan Zhu. "Sorption of apolar and polar organic contaminants by waste tire rubber and its chars in single- and bi-solute systems." Environmental Pollution 159, no. 4 (April 2011): 850–57. http://dx.doi.org/10.1016/j.envpol.2011.01.002.
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Li, Yunchao, Xianhua Wang, Huawei Song, Jingai Shao, Hongtao Ma, and Hanping Chen. "Phenols production from online catalytic conversion of corn stalk pyrolysis vapors using char in-situ." BioResources 13, no. 3 (May 10, 2018): 4884–96. http://dx.doi.org/10.15376/biores.13.3.4884-4896.
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Char in-situ (char[is]) obtained from corn stalk pyrolysis was evaluated as a catalyst to upgrade corn stalk pyrolysis vapors. A catalyst evaluation device was introduced to conduct the experiments. The effects of reaction temperature and char[is] dose on catalytic performances in biomass pyrolysis were evaluated. The results showed that the char in-situ had a remarkable effect on the pyrolysis products. Under the action of char[is], the primary compounds of pyrolysis vapors were catalytically converted into phenolic products, such as phenol and 4-ethyl-phenol, while the acetic acid content was evidently reduced. The product selectivity was not dependent on the polar functional groups on the char[is]’s surface according to the Fourier transform infrared (FTIR) results, but might have been dependent on the mesoporous structure and the basicity sites of the charis as well as the metallic species in the char[is]. A possible reaction mechanism for phenols production and acetic acid inhibition was proposed.
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Dixit, Lena, Michael Puente, and Kimberly G. Yen. "Characteristics of Anterior Lens Opacities in Children." Open Ophthalmology Journal 11, no. 1 (April 28, 2017): 84–88. http://dx.doi.org/10.2174/1874364101711010084.
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Background: Anterior lens opacities (ALO) are found in 3-14% of pediatric patients with cataracts. No clear guidelines exist in the management and treatment of these cataracts. Objective: To evaluate pediatric patients with anterior lens opacities and assess rate of amblyopia and need for surgery over time. Methods: A retrospective chart review was performed on patients with unilateral and bilateral anterior lens opacities (ALOs) seen between January 2008 and December 2014. Size, location, and type of ALO were noted. Refractive error, necessity for treatment of amblyopia, and interventions were recorded. Results: A total of 31 patients were included in the study. 17 patients had unilateral ALOs and 14 had bilateral ALOs. The majority of the cataracts (90.3%) were centrally located. The most common type of cataract was the polar type of cataract and the vast majority (48.4%) was < 1mm in size. 38.7% of patients had concurrent ocular conditions and 9.7% had systemic associations. 28.6% of patients with bilateral cataracts and 35.3% of the patients with unilateral cataracts were treated for amblyopia. Three patients required cataract surgery. Conclusion: About half of anterior lens opacities are less than 1mm in size and the majority are of the polar type. Risk of amblyopia in these patients is higher than in the general population. Anisometropia is the most common cause of amblyopia. Ocular associations are seen at a relatively high frequency and systemic associations can occur but are uncommon. The need for surgical intervention is infrequent; however, growth of ALOs and associated cortical changes may be risk factors for surgery.