Journal articles on the topic 'Northern Mathematical models'
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Dambacher, Jeffrey M., Peter C. Rothlisberg, and Neil R. Loneragan. "Qualitative mathematical models to support ecosystem-based management of Australia's Northern Prawn Fishery." Ecological Applications 25, no. 1 (January 2015): 278–98. http://dx.doi.org/10.1890/13-2030.1.
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Nikonorov, Valentin, Andrei Kutuzov, Viktor Nikonorov, Irina Bagaeva, and Anna Letta. "Dewaxing models digitalization in the mathematical model of winter diesel fuel production." E3S Web of Conferences 258 (2021): 11004. http://dx.doi.org/10.1051/e3sconf/202125811004.
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The climatic features of Russia, as well as the need for the development of the Arctic and the Great Northern Sea Route, require an increase in the production of winter diesel fuel. The object of the study is obtaining winter diesel fuel. The subject of the study is digitalizing oil-refining processes by building the mathematical model of winter diesel fuel production for the case of combining dewaxing regimes taking into account the logistical aspect. Main research methods: retrospective data analysis, synthesis, comparison, optimization theory methods. A literary review was carried out, the main methods for improving the low-temperature properties of winter diesel fuel were revealed. Study hypothesis: a combination of dewaxing regimes will increase the yield of denormalizate and, accordingly, winter diesel fuel. The authors for each mode of dewaxing compiled a mathematical model. Then, the authors constructed a mathematical model of obtaining winter diesel fuel for a combination of dewaxing regimes and taking into account the logistical aspect. The obtained mathematical model can be used to obtain the required amount of winter diesel fuel with compliance with quality requirements and taking into account the logistical aspect.
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Gomes, Francileni Pompeu, Osvaldo Resende, Elisabete Piancó de Sousa, Juliana Aparecida Célia, and Kênia Borges de Oliveira. "Application of Mathematical Models and Thermodynamic Properties in the Drying of Jambu Leaves." Agriculture 12, no. 8 (August 18, 2022): 1252. http://dx.doi.org/10.3390/agriculture12081252.
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Jambu is a vegetable originally from the northern region of Brazil, has bioactive properties, being little explored by other regions, due to its high peresivity. And one of the methods to increase the shelf life of plant products is the removal of water. The objective of this work was to evaluate the drying kinetics of jambu leaf mass. Two treatments were carried out: The mass of fresh jambu leaves and the mass of fresh jambu leaves with the addition of drying foam, both submitted in an oven with forced air circulation at temperatures (50, 60 and 70 °C and thickness of 1.0 cm). The proximate composition of the materials was performed before and after drying. Twelve mathematical models were tested on drying kinetics data and thermodynamic properties were calculated. The parameters of the proximate composition for the mass of leaves and foam after drying were: Moisture content of (2 to 7%), ash content of (13 to 17%), protein content of (22 to 30%), lipids of (0.6 to 4%) and total titratable acidity (0.20 to 0.28%) of tartaric acid. The models that best fit the experimental data to describe the drying kinetics of jambu masses were: Wang & Singh. The use of foam mat presented higher values of effective diffusion coefficient and activation energy and lower values of enthalpy and entropy, reducing the drying time.
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Abeuov, S. K., O. D. Shoykin, and V. A. Kamkin. "Mathematical models for predicting the level of potatoes nutrition from the soil chemical composition in the Northern Kazakhstan conditions." IOP Conference Series: Earth and Environmental Science 954, no. 1 (January 1, 2022): 012003. http://dx.doi.org/10.1088/1755-1315/954/1/012003.
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Abstract The authors of the article presented a visual technique for programming the yield of potato tubers by using mathematical models of the relationship with the chemical composition of the soil. The content of N-NO3 and P2O5 varied in the range of 14.7-35.0 mg/kg and 37.1-39.0 mg/kg of soil. The increase in the content of these nutrients was accompanied by an increase in the productivity of potato tubers from 1 ha. The results of the study showed that the yield value is closely related to the content of N-NO3 and P2O5 in the soil in the initial phase of crop growth. The verification of the calculation methods showed a forecast error by comparing the actual yield data with the predicted results. The established quantitative indicators with the help of mathematical communication models make it possible to diagnose the value of potato yield and normalize the effect of fertilizers.
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Vassiliadis, Chris, and John Mylonakis. "PLANNING A PRODUCT FOR TOURING DESTINATIONS THROUGH THE USE OF SPATIAL MATHEMATICAL ANALYSIS." Tourism and hospitality management 12, no. 2 (December 2006): 71–82. http://dx.doi.org/10.20867/thm.12.2.6.
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Mathematical models provide spatial analysis to help complex decision-making and can be successfully applied to product planning in tourism. This paper presents a case study, and suggests one process by which planning agencies may evaluate the railway stations in the Northern Greece network. Six geographical points of distinction are identified for promotion based on linear-nearest neighbor analysis and the connectivity index. A functional diagram evaluates each point based on infrastructure, natural and cultural attractions. Finally, these indicators suggest marketing considerations, which may lend support to Management or stakeholders’ discussions to maximize the geographic points.
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Sazonov, A. A., I. N. Krylenko, A. N. Amerbaev, E. V. Zavyalova, N. K. Semenova, L. S. Odoev, and N. L. Frolova. "Application of the synthesis of mathematical models to study the characteristics of flooding of the Northern Dvina River." IOP Conference Series: Earth and Environmental Science 263 (May 13, 2019): 012016. http://dx.doi.org/10.1088/1755-1315/263/1/012016.
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Klein, Michael J. "Predicting Prehistoric Settlement in the Northern Neck of Virginia: The Richmond County Assessment Survey Methodology." North American Archaeologist 16, no. 4 (April 1996): 317–42. http://dx.doi.org/10.2190/u1gf-5c2l-xq8f-q8bc.
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Cultural Resource Management studies have identified a variety of site types and locations and generated data suited to statistical and predictive analysis. Unfortunately, predictive models often include unwarranted assumptions about the structure of the environment and the mathematical distribution of the data. Statistical and graphic approaches drawn from Exploratory Data Analysis, combined with sampling of the environment, promote evaluation of the potential of environmental variables for predicting site locations. Analysis of data from the Richmond County Archaeological Assessment illustrates these points.
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Ferguson, N. M., C. A. Donnelly, M. E. J. Woolhouse, and R. M. Anderson. "The epidemiology of BSE in cattle herds in Great Britain. II. Model construction and analysis of transmission dynamics." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 352, no. 1355 (July 29, 1997): 803–38. http://dx.doi.org/10.1098/rstb.1997.0063.
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Mathematical models that describe the key processes determining the pattern of the bovine spongiform encephalopathy (BSE) epidemic in British cattle are derived that allow for infection from feed as well as maternal and direct horizontal transmission. Heterogeneous susceptibility classes are also incorporated into the analysis. Maximum likelihood methods are used to estimate parameters and to obtain confidence intervals from available experimental and epidemiological data. A comprehensive sensitivity analysis of all model parameters and distributional assumptions is presented. Additional validation is provided by fitting the model to independent data collected in Northern Ireland. Model estimates and predictions based on BSE case data for Great Britain and Northern Ireland, together with their implications, are reviewed, and future research priorities discussed.
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Sytnyk, S. A. "PHYTOTOMASS OF ROBINIA PSEUDOACACIA L. TRUNK COMPONENTS IN THE PLANTED BLACK LOCUST STANDS WITHIN NORTHERN STEPPE ZONE OF UKRAINE." Forestry and Forest Melioration, no. 132 (February 5, 2018): 141–47. http://dx.doi.org/10.33220/1026-3365.132.2018.141.
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The results of simulation of the above-ground phytomass of the components of Black locust tree trunks in the planted stands within the Northern Steppe zone of Ukraine are presented. Correlation and statistical analyses of the data set from model trees were carried out. A reliable strong correlation between the formation of the trunk timber volume and the volume of the trunk in the bark and the values of the diameter of the trunk and the height of the trees were established. The mathematical dependences for estimating the volume of the black locust trunk fractions, namely, the volume of the trunk timber, the volume of the trunk bark and the volume of the trunk in the bark, were developed as two- and three-factor mathematical models. The graphical interpretation of changes in the trunk volume in the bark of trees at the constant height was presented under the developed mathematical model. The results of the development of normative support for evaluation of components of the trunk phytomass in freshly cut and absolutely dry conditions were given.
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Kroepsch, Adrianne C. "Groundwater Modeling and Governance: Contesting and Building (Sub)Surface Worlds in Colorado’s Northern San Juan Basin." Engaging Science, Technology, and Society 4 (March 1, 2018): 43. http://dx.doi.org/10.17351/ests2018.208.
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As groundwater use has surged globally and computing power has grown, groundwater modeling has become a regular feature of subsurface-oriented governance. Our improved ability to “see” underground with models has not, however, generated epistemic consensus on the inner workings of subsurface systems. Here, I ask how and why that is the case. I pursue this line of inquiry in the context of groundwater governance in the American West. Specifically, I trace a decade of groundwater modeling at the heart of a protracted and legally influential groundwater dispute in the state of Colorado to show how models served as mathematical spaces for competing subsurface stakeholders to test and contest opposing visions of groundwater flows, rights, and responsibilities. Drawing from the Science & Technology Studies literature on global climate modeling, I argue that groundwater models are more than simulations of subsurface systems; they are tools of “world building” that embed, enact, and also circumscribe subsurface politics.
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Deumlich, D., A. Jha, and G. Kirchner. "Comparing measurements, 7Be radiotracer technique and process-based erosion model for estimating short-term soil loss from cultivated land in Northern Germany." Soil and Water Research 12, No. 3 (June 28, 2017): 177–86. http://dx.doi.org/10.17221/124/2016-swr.
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Due to changing climate and irregular weather patterns, event-based soil loss and sediment yield have become important issues in the agricultural areas. Several mathematical models and prediction methodologies have been used to estimate event-based soil loss and soil redistribution based on soil types, land management, hydrology and local topography. The use of short-lived beryllium-7 as a means of estimating event-based soil erosion/deposition rates has become an alternative to the traditional soil loss measurement methods. A new erosion model taking into account the movement of <sup>7</sup>Be in soils has been presented recently. In order to direct the attention to the potential offered by this technique (measurements and mathematical model), a two-year study was performed at the erosion plots in Müncheberg, Germany, and twelve individual erosion rates were estimated. This paper presents a systematic comparison of the non-steady state <sup>7</sup>Be model with the process-based erosion model EROSION-3D and measured data. The results demonstrate a close consistency between the erosion rates estimated by erosion models and the estimates provided by the <sup>7</sup>Be model and can therefore be seen as a promising contribution to validating the use of this radionuclide to document short-term soil redistribution within the plot and deposited sediment at the bottom of the plot.
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JD, Williams, Ishaya I, Victor S, Stephen M, Yusuf S. Sanda, and Okpalaonwuka CT. "EMPIRICAL MODELS FOR CORRELATION OF CLEARNESS INDEX WITH CLOUD INDEX AT ZARIA, KADUNA STATE." International Journal of Engineering Applied Sciences and Technology 6, no. 7 (November 1, 2021): 63–67. http://dx.doi.org/10.33564/ijeast.2021.v06i07.011.
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In this study, the monthly average daily values of global solar radiation and relative sunshine hours on a horizontal surface over a period of five years (2011-2015) using multi-linear polynomial form of the AngstromPrescott model have been developed to estimate global solar radiation for Zaria (northern part of Nigeria) which lies on latitude 11°04'N and longitude 7o 42' E. Five different mathematical correlations models (first order, second order, exponential, powered, and logarithmic) was considered and it was found that first order, second order polynomials, exponential and powered gives a good model for estimating total solar radiation in Zaria. The agreement between the measured values (that obtained from the Nigerian Meteorological Agency) and the computed values is remarkable and the models are recommended for Zaria
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Brigolin, Daniele, Erika Maria Diletta Porporato, Giuseppe Prioli, and Roberto Pastres. "Making space for shellfish farming along the Adriatic coast." ICES Journal of Marine Science 74, no. 6 (March 14, 2017): 1540–51. http://dx.doi.org/10.1093/icesjms/fsx018.
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Abstract This work focuses on the selection of new areas for shellfish farming along the coast of the Northern Adriatic Sea (Italy). Shellfish site suitability was assessed by means of a methodology based on Spatial Multi-Criteria Evaluation (SMCE), which provided the framework to combine mathematical models and operational oceanography products. Intermediate level criteria considered in the analysis included optimal growth conditions, environmental interactions, and socio-economic evaluation (e.g. organic carbon deposition; distance to harbour). Results showed that the whole coastal area comprised within 0 and 3 nm is highly suitable for farming of mussel, while the area comprised between 3 and 12 nm is divided between a highly suitable northern part, and a less suitable southern one. Seven different scenarios of development of shellfish aquaculture industry were explored. The introduction of a new species, and the assessment of the exposure to storm events are specific aspects taken into account in development scenarios. Results show that the degree of suitability for shellfish aquaculture in this area would not change dramatically with the introduction of oyster farming. Furthermore, results highlight that: (i) the growth potential in this area is high; (ii) the space with suitability index >0.5 increases when prioritizing the optimal growth condition criteria, and (iii) the socio-economic is the most restrictive Intermediate Level Criteria. Results were discussed by deriving general lessons concerning the use of SMCE in aquaculture space allocation, from the specific application in the Northern Adriatic Sea. Challenges and opportunities related to the proposed methodological framework, with particular reference to the use of resources provided by remote sensing and operational oceanography by means of mathematical models, were also discussed. Results can support a science-based identification of allocated zones for aquaculture in order to avoid conflicts, and promote sustainable aquaculture in the Mediterranean Sea, where the space for these activities is becoming increasingly limited.
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Mangiarotti, Sylvain, Laurent Drapeau, and Christophe Letellier. "Two chaotic global models for cereal crops cycles observed from satellite in northern Morocco." Chaos: An Interdisciplinary Journal of Nonlinear Science 24, no. 2 (June 2014): 023130. http://dx.doi.org/10.1063/1.4882376.
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Saunders, Mike R., and Klaus J. Puettmann. "Use of Vegetational Characteristics and Browsing Patterns to Predict Deer Damage in Eastern White Pine (Pinus strobus) Plantations." Northern Journal of Applied Forestry 16, no. 2 (June 1, 1999): 96–102. http://dx.doi.org/10.1093/njaf/16.2.96.
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Abstract Browsing of seedlings by white-tailed deer (Odocoileus virginianus) can make natural and artificial forest regeneration difficult. Few mathematical models predict deer browsing within and between sites, giving managers only landscape-level characteristics, such as deer population levels and yearly snowfall measurements, to determine where deer-protective measures should be installed. This study described browsing patterns and assessed influence of vegetational characteristics on browsing. Predictive models were developed using overstory and understory measurements, and browsing reconstructions of individual seedlings within eight eastern white pine (Pinus strobus) plantations in northern Minnesota. Results indicated that deer concentrate browsing on terminal leaders in shorter seedlings, shifting to laterals as seedlings approach browsing height limits (140 cm).Damage models were site-specific. The vertical and horizontal distribution of understory vegetation and the presence of alternative food sources influenced the probability of browsing. Future models should incorporate these measures as well as browse selection patterns, landscape-level characteristics,and past deer activity. North. J. Appl. For. 16(2):96-102.
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Aladjev, G. A., O. V. Evstafiev, V. S. Mingalev, G. I. Mingaleva, E. D. Tereshchenko, and B. Z. Khudukon. "Interpretation of ionospheric F-region structures in the vicinity of ionisation troughs observed by satellite radio tomography." Annales Geophysicae 19, no. 1 (January 31, 2001): 25–36. http://dx.doi.org/10.5194/angeo-19-25-2001.
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Abstract. Tomographic images of the spatial distribution of electron density in the ionospheric F-region are presented from the Russian-American Tomography Experiment (RATE) in November 1993 as well as from campaigns carried out in northern Scandinavia in November 1995 and in Russia in April 1990. The reconstructions selected display the ionisation troughs above the tomographic chains of receivers during geomagnetically quiet and disturbed periods. Two mathematical models of the high-latitude ionosphere developed in the Polar Geophysical Institute have been applied for interpretation of the observed tomographic images.Key words. Ionosphere (electric fields and currents; ion chemistry and composition; plasma convection)
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Marchenko, S. S., L. E. Mamedova, and M. E. Gogolyukhina. "Economic Aspects of Modernization of Vessels Operating on the Northern Sea Route." Economics and Management 27, no. 6 (July 23, 2021): 471–78. http://dx.doi.org/10.35854/1998-1627-2021-6-471-478.
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Aim. The presented study aims to develop methodological tools for assessing the economic aspects of the modernization of vessels operating on the Northern Sea Route.Tasks. The authors address the problem of economic justification for the modernization and improvement of efficiency of mixed river-sea cargo transport vessels operating on the Northern Sea Route; develop an algorithm and methodology for assessing the economic aspects of the modernization of vessels operating on the Northern Sea Route; determine the economic effect of upgrading the register class of modernized river vessels. Methods. This study proposes an algorithm for the economic assessment of the modernization of river and sea vessels, which includes the constructed mathematical models for upgrading the class of the vessel and forecasting net income.Results. The authors assess the economic viability of upgrading the register class of modernized vessels of the Omskiy and Sibirskiy type, which could become more competitive in the future and continue to operate on the Northern Sea Route with high economic efficiency, ensuring the supply of goods to northern Russian territories; form the financial profile of investment projects for the modernization of the considered types of vessels.Conclusions. Modernizing and upgrading the register class of river vessels and mixed river-sea vessels is a promising direction for adding modern cargo ships to the Russian fleet operating on the Northern Sea Route, particularly in the context of deliveries of goods to northern Russian territories. The performed economic assessment of the modernization of a Sibirskiy-type vessel according to the developed algorithm confirms the economic viability of modernizing mixed river-sea vessels.
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Makinia, J., M. Swinarski, and E. Dobiegala. "Experiences with computer simulation at two large wastewater treatment plants in northern Poland." Water Science and Technology 45, no. 6 (March 1, 2002): 209–18. http://dx.doi.org/10.2166/wst.2002.0108.
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Mathematical modelling and computer simulation have became a useful tool in evaluating the operation of wastewater treatment plants (WWTPs) in terms of nutrient removal capability. In this study, steady-state simulation results for two large biological nutrient removal WWTPs are presented. The plants are located in two neighbouring cities Gdansk and Gdynia in northern Poland. Simulations were performed using a pre-compiled model and layouts (MUCT and Johannesburg processes) implemented in the GPS-X simulation package. The monthly average values of conventional parameters, such as COD, Total Suspended Solids, total N, N-NH4+, P-PO4− were used as input data. The measured effluent concentrations of COD, N-NH4+, N-NO3− and P-PO4− as well as reactor MLSS were compared with model predictions. During calibration, performed from the process engineering perspective, default values of only five model parameters were changed. The opportunities for further applications of such models in municipal WWTPs are discussed.
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Yakhyayev, Aydin, Elshad Gurbanov, Farzaliyev Vahid, and Farid Seyfullayev. "The regeneration of Oriental beech (Fagus orientalis Lipsky) share in the secondary hornbeam stands using." Journal of Forest Science 67, No. 1 (January 12, 2021): 12–20. http://dx.doi.org/10.17221/22/2020-jfs.
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In the paper, the results of the complex cuttings were presented in the secondary hornbeam stands with the aim of regenerating the natural beech stands in the northern regions of Azerbaijan. For this purpose, three complex cutting procedures were carried out with a recurrence at 5 and 10 years in four sites of the secondary hornbeam stands in the northern regions. The experimental plots were characterised with: a stand density of 0.5–0.7, the age of the forest stands of 60–130 years, undergrowth of 12–25 years, a stand volume of 130–200 m3·ha–1, the beech percentage in the composition of stands of 17–28%, hornbeam 62–79% spread over the southern and northern slopes of the mountains. As a result of the complex cuttings, the share of beech trees in the composition of the parent stands increased 2.2–3.0 times. During cutting, the share of beech trees, as a part of undergrowth, increased 3.8–4.3 times. Based on the data, mathematical models were established reflecting the dynamics of the numbers of the undergrowth and the total stand volume of the forest stands depending on the participation percentage of beech trees in the parent stand.
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Attom, Mousa F., and Samer Barakat. "Investigation of three methods for evaluating swelling pressure of soils." Environmental and Engineering Geoscience 6, no. 3 (August 1, 2000): 293–99. http://dx.doi.org/10.2113/gseegeosci.6.3.293.
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Abstract Determination of the swelling pressure of six types of clayey soils obtained from northern Jordan were measured using three methods, the Free Swell method, Different Pressure method, and the Zero Swell method. These methods show different values in swelling pressure of the soil. For all six soils, the Free Swell method provided the highest value, whereas the Different Pressure method provided the lowest. Discrepancy in the value of swelling pressure among the methods increases with lower initial water content, higher plasticity index, and clay content. This paper compares the three different methods for evaluating soil swelling pressure and presents mathematical models to predict the soil swelling pressure for each method.
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Kotsyura, O. O. "Modeling using regression analysis of linear sizes of molars depending on the cephalometric indices of practically healthy men of the Northern and Southern regions of Ukraine." Biomedical and Biosocial Anthropology, no. 30 (March 29, 2018): 68–74. http://dx.doi.org/10.31393/bba30-2018-10.
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For more precise odontometry, taking into account the individual craniotypologicalfeatures of the patient, mathematical modeling should be used, which will significantlyimprove the quality of the medical diagnostic and treatment process in orthodontics. Thepurpose of the study is to construct and analyze a regression model of computed-tomographic size of molars, depending on the features of cephalometric indices ofpractically healthy men of the Northern and Southern regions of Ukraine. Computed-tomographic study of molars with the following odontometry and cephalometry of 32practically healthy men of the Northern region of Ukraine - residents from Zhytomyr, Kyiv,Chernihiv and Sumy regions and 33 men of the Southern region of Ukraine - residentsfrom Odessa, Nikolaev, Kherson, Zaporizhzhya regions and Crimea. The construction ofregression models of individual linear sizes of molars, depending on the cephalometricindices, was performed using the statistical software package "Statistica 6.1". As a resultof our research, we have constructed reliable models of linear computed-tomographicsizes of molars of the upper and lower jaws in practically healthy men of the North [3models of mesio-distal dimensions (R2 = 0.576-0.685), to which most often include thelength of the body of the mandible on the right (16.7%), the smallest width of the head,the depth of the nose and the craniotype (by 11.1%); 2 models of vestibular-tonguedimensions (R2 = 0.657 and 0.767), which most often include the transverse arc andthe smallest width of the head (15.4%); 2 models of crown height (R2 = 0.519 and0.557)] and Southern [4 models of mesio-distal dimensions (R2 = 0.508-0.798), whichmost often include the largest head length, average facial width, height of the upperface, physiological face length, width of the lower jaw, nose depth and external eyewidth (8.3%); 6 models of vestibular-tongue dimensions (R2 = 0.504-0.756), whichmost often include external eye width (13.2%), physiological facial length, intercostalwidth and mouth width (10.5%), maximum head width, length and height of the nose (by7.9%), transverse arc, height of the upper face and distance between the nasion andinter-incisive point (by 5.3%); 2 models of crown height (R2 = 0.527 and 0.748), whichmost often include inter-orbital width and mouth width (14.3%)] regions of Ukraine.Thus, in practically healthy men from the Northern and Southern administrative-territorialregions of Ukraine, based on the characteristics of cephalometric indicators, craniotypeand face type, reliable regression models (with determination coefficient R2 greater than0.5) of individual linear computed-tomography sizes of molars of the upper and lowerjaws (out of 40 possible 7 for Northern and 12 for Southern regions of Ukraine).
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El Mansouri, Fouad, Guillermo Pelaz, Antonio Morán, Joaquim C. G. Esteves Da Silva, Francesco Cacciola, Hammadi El Farissi, Hatim Tayeq, Mohammed Hassani Zerrouk, and Jamal Brigui. "Efficient Removal of Eriochrome Black T Dye Using Activated Carbon of Waste Hemp (Cannabis sativa L.) Grown in Northern Morocco Enhanced by New Mathematical Models." Separations 9, no. 10 (October 3, 2022): 283. http://dx.doi.org/10.3390/separations9100283.
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In the present work, the adsorption behavior of Eriochrome Black T (EBT) on waste hemp activated carbon (WHAC) was examined. The surface of the WHAC was modified by H3PO4 acid treatment. The surface and structural characterization of the adsorbents was carried out using Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analysis. The effect of influential adsorption parameters (pH, contact time, dosage, and initial concentration) on the adsorption of EBT onto WHAC was examined in batch experiments; some adsorption parameters such as pH, concentration and dose were improved by new mathematical models. The adsorption behavior of EBT on the surfaces of WHAC was evaluated by applying different isotherm models (Langmuir, Freundlich, Temkin and Dubinin–Radushkevich) to equilibrium data. The adsorption kinetics was studied by using pseudo-first-order, pseudo-second-order, Elovich and intraparticle models on the model. Adsorption followed the pseudo-second-order rate kinetics. The maximum removal of EBT was found to be 44–62.08% by WHAC at pH = 7, adsorbent dose of 10–70 mg, contact time of 3 h and initial dye concentration of 10 mg.L−1. The maximum adsorption capacities were 14.025 mg.g−1 obtained by calculating according to the Langmuir model, while the maximum removal efficiency was obtained at 70 mg equal to 62.08% for the WHAC. The adsorption process is physical in the monolayer and multilayer.
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Kravchenko, Alexander, Boris Gerasimov, Evgeniy Loskutov, Alexander Okrugin, Larisa Galenchikova, and Vasily Beryozkin. "Statistical Models of the Distribution of Chemical Elements in Precambrian Rocks of the Siberian Craton." Separations 8, no. 3 (February 25, 2021): 23. http://dx.doi.org/10.3390/separations8030023.
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Natural chemical systems are an excellent object for studying the properties of various elements. The most diverse and informative geological complexes are crystalline rocks of the Precambrian. These rocks are exposed near the northern and southern margins of the Siberian craton. The chemical composition of rocks, the contents of impurity elements, and metals were studied by us using chemical and spectral analysis methods. Microprobe studies were performed. Using regression and multivariate statistical methods of analysis, the regularities of the distribution of chemical elements were found. It is shown that the distribution of precious metals and carbon dioxide in rocks is attributed to their chemical properties and comparable with close in-chemical properties’ rock-forming elements. It is found that the factor analysis reflects the uniform regularities of the distribution of elements in different regions and rocks. These regularities are similar on macro and micro levels. Comparison of the distribution patterns with the results of geochemical and petrological studies of other authors shows the leading role of the redox potential and acidity of the environment in the formation of rocks and minerals. The role of mathematical statistics for solving problems of chemical petrology and chemical systems analysis is underlined.
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Müller, Felix L., Claudia Wekerle, Denise Dettmering, Marcello Passaro, Wolfgang Bosch, and Florian Seitz. "Dynamic ocean topography of the northern Nordic seas: a comparison between satellite altimetry and ocean modeling." Cryosphere 13, no. 2 (February 20, 2019): 611–26. http://dx.doi.org/10.5194/tc-13-611-2019.
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Abstract. The dynamic ocean topography (DOT) of the polar seas can be described by satellite altimetry sea surface height observations combined with geoid information as well as by ocean models. The altimetry observations are characterized by an irregular sampling and seasonal sea ice coverage complicating reliable DOT estimations. Models display various spatiotemporal resolutions but are limited to their computational and mathematical context and introduced forcing models. In the present paper, ALES+ retracked altimetry ranges and derived along-track DOT heights of ESA's Envisat and water heights of the Finite Element Sea Ice-Ocean Model (FESOM) are compared to investigate similarities and discrepancies. The goal of the present paper is to identify to what extent pattern and variability of the northern Nordic seas derived from measurements and model agree with each other, respectively. The study period covers the years 2003–2009. An assessment analysis regarding seasonal DOT variabilities shows good agreement and confirms the dominant impact of the annual signal in both datasets. A comparison based on estimated regional annual signal components shows 2–3 times stronger amplitudes of the observations but good agreement of the phase. Reducing both datasets by constant offsets and the annual signal reveals small regional residuals and highly correlated DOT time series (Pearson linear correlation coefficient of at least 0.67). The highest correlations can be found in areas that are ice-free and affected by ocean currents. However, differences are visible in sea-ice-covered shelf regions. Furthermore, remaining constant artificial elevations in the observational data can be attributed to an insufficient representation of the used geoid. In general, the comparison results in good agreement between simulated and altimetry-based descriptions of the DOT in the northern Nordic seas.
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Frisman, E. Ya, O. L. Zhdanova, and A. E. Kuzin. "The Outcome of Northern Fur Seal Harvesting: The Results of Calibration of Mathematical Models Based on Observation Data (the Example of Tyulenii Island Population)." Russian Journal of Ecology 50, no. 2 (March 2019): 161–71. http://dx.doi.org/10.1134/s1067413619020048.
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Fabbri, Andrea G., and Antonio Patera. "Spatial Uncertainty of Target Patterns Generated by Different Prediction Models of Landslide Susceptibility." Applied Sciences 11, no. 8 (April 8, 2021): 3341. http://dx.doi.org/10.3390/app11083341.
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This contribution exposes the relative uncertainties associated with prediction patterns of landslide susceptibility. The patterns are based on relationships between direct and indirect spatial evidence of landslide occurrences. In a spatial database constructed for the modeling, direct evidence is the presence of landslide trigger areas, while indirect evidence is the presence of corresponding multivariate context in the form of digital maps. Five mathematical modeling functions are applied to capture and integrate evidence, indirect and direct, for separating landslide-presence areas from the areas of landslide assumed absence. Empirical likelihood ratios are used first to represent the spatial relationships. These are then combined by the models into prediction scores, ordered, equal-area ranked, displayed, and synthesized as prediction-rate curves. A critical task is assessing how uncertainty levels vary across the different prediction patterns, i.e., the modeling results visualized as fixed, colored groups of ranks. This is obtained by a strategy of iterative cross validation that uses only part of the direct evidence to model the pattern and the rest to validate it as a predictor. The conducted experiments in a mountainous area in northern Italy point at a research challenge that can now be confronted with relative rank-based statistics and iterative cross-validation processes. The uncertainty properties of prediction patterns are mostly unknown nevertheless they are critical for interpreting and justifying prediction results.
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Leonov, V. A., A. V. Bagrov, G. F. Attia, A. M. Abdelaziz, and R. Ghoneim. "Study the combustion processes of space debris in the Earth’s atmosphere by meteoric TV camera." Applied Mathematics and Nonlinear Sciences 2, no. 2 (November 15, 2017): 473–78. http://dx.doi.org/10.21042/amns.2017.2.00038.
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AbstractSpace debris of millimeter dimensions is almost not detectable by normal methods of observation from Earth. However, particles of such sizes can cause damage to the spacecraft. and even eliminate it. Estimating the status of impurity of near-Earth space mainly based on mathematical models, which are confirmed only for large particles. The millimetric fractions of space debris elements remain unexplored. In case of invasion of debris particles into the planet’s atmosphere, they burn down as well as meteoric particles of natural origin. In this work, the observation technique of separation of debris particles and particles of natural origin is described. Also, the results of the detection of particles from space debris received during the TV observations on the wide-angle camera patrol camera FAVOR (Russia, Northern Caucasus).
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Kershenbaum, Arik, Lewi Stone, Burt P. Kotler, and Leon Blaustein. "Predation Risk can Drive Cycles in Zoonotic Disease Prevalence." Israel Journal of Ecology and Evolution 56, no. 3-4 (May 6, 2010): 281–95. http://dx.doi.org/10.1560/ijee.56.3-4.281.
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The recent increase in human cases of leishmaniasis in northern Israel has been accompanied by dramatic anthropogenic changes in the landscape that affect the behavioral ecology of one of its mammalian reservoirs, the rock hyrax,Procavia capensis.Hyraxes migrate from refuge to refuge, presumably following forage availability, but their migration patterns are strongly affected by the availability and spacing of the rock piles that form their den sites and give them protection from predators. We therefore expect changes in predation risk to influence the ability of hyrax groups to migrate from site to site. We combine mathematical metapopulation models of hyrax behavioral ecology, as well as compartmental models of disease dynamics, to investigate the effect of microhabitat alteration and varying perceived predation risk on disease incidence. Our models indicate that such fine-scale alterations in predation risk can have surprising effects on pathogen prevalence, leading to the emergence of epizootic cycles. Regular (predictable) cycles and chaotic (unpredictable) cycles may occur as predation risk is reduced. Under some conditions, cycles may result from very small changes in predation risk or environmental conditions. Our models show regions of sensitive dependence on environmental and predatory conditions, leading us to predict the possibility of the emergence of chaotic disease cycles as the result of small environmental disturbances.
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Menendez, Hector M., and Jameson Brennan. "82 Application of Precision Sensor Technologies, Real-time Data Analytics, and Dynamic Models on Extensive Western Rangeland Grazing Systems." Journal of Animal Science 99, Supplement_3 (October 8, 2021): 43–44. http://dx.doi.org/10.1093/jas/skab235.076.
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Abstract Approximately 40% of the land use within the Northern Great Plains is dedicated to livestock production, with much of the 89.9 million head of cattle and calves in the U.S. concentrated in this area. Precision livestock management has ushered in a new era of sensors and technology to monitor individual animal’s health, reproductive, and nutritional status in real-time to improve efficiency. Despite these advances, most of the research has been conducted on dairy operations or within feedlot settings. Incorporation on extensive rangeland production systems remains relatively absent (Brennan et al., 2021). This is primarily due to difficulties in studying animals on rangelands caused by heterogeneity of forage resources, variable environmental conditions, and challenges associated with accessing information across vast distances, often without cellular or internet connection. Advances in communication technology are increasingly connecting remote areas, creating new opportunities to improve livestock production efficiency on extensive rangelands using precision technology. Numerous challenges still exist, including applying and integrating multiple technologies across platforms, effectiveness in a real-world setting, technical skills, and knowledge to utilize real-time data, and achieving economic return for livestock producers. Specifically, we discuss the application of precision technologies and mathematical models for improving ruminant nutrition in rangeland systems (Menendez and Tedeschi, 2020). Opportunities exist to refine or develop the next generation of equations/models that more adequately represent nutrient dynamics such as diet selection, supplementation, movement, behavior, water intake, feed conversion efficiency, heat/cold stress, and gain on an individual animal basis. However, effective adoption and adaptability of new technologies/data analytics merit the consideration of potential intended-and-unintended consequences, such as producer dependency on complex hardware and software systems. Hence, precision capabilities coupled with mathematical models are likely the next step to substantially enhance livestock performance in extensive systems when coupled with feasible and reliable long-term strategies.
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Alshboul, Odey, Ali Shehadeh, Ghassan Almasabha, Rabia Emhamed Al Mamlook, and Ali Saeed Almuflih. "Evaluating the Impact of External Support on Green Building Construction Cost: A Hybrid Mathematical and Machine Learning Prediction Approach." Buildings 12, no. 8 (August 16, 2022): 1256. http://dx.doi.org/10.3390/buildings12081256.
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As a fundamental feature of green building cost forecasting, external support is crucial. However, minimal research efforts have been directed to developing practical models for determining the impact of external public and private support on green construction projects’ costs. To fill the gap, the current research aims to develop a mathematical model to explore the balance of supply and demand under deflationary conditions for external green construction support and the accompanying spending adjustment processes. The most current datasets from 3578 green projects across Northern America were collected, pre-processed, analyzed, post-processed, and evaluated via cutting-edge machine learning (ML) techniques to retrieve the deep parameters affecting the green construction cost prediction process. According to the findings, public and private investments in green construction are projected to decrease the cost of green buildings. Furthermore, the impact of public and private investment on green construction cost reduction during deflationary periods is more significant than its influence during inflation. As a result, decision-makers may utilize the suggested model to monitor and evaluate the yearly optimal external investment in green building construction.
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Psilovikos, Aris, and Christos Tzimopoulos. "Comparison of quadratic and non-linear programming (QP and NLP) optimization models in groundwater management." Journal of Hydroinformatics 6, no. 3 (July 1, 2004): 175–85. http://dx.doi.org/10.2166/hydro.2004.0014.
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This project is concerned with the comparison of two algorithms used in groundwater management models, based on Quadratic Programming (QP) and Non-linear Programming (NLP) models. A quadratic objective function is used and solved in two different ways. The first one is the application of the Karush–Kuhn–Tücker (KKT) conditions and Wolfe's algorithm, which are used in solving QP models. The second one is the Conjugate Gradient Method (CGM), which is used in solving NLP models. Two additional ‘shell programs’ are created to formulate the results of the management model. These results are organized in a Mathematical Programming System (MPS) file. This is the management model output and contains the response matrix coefficients and all the management model details in a coded format. The MPS data file is formatted via the two shell programs, constituting the import data file for the optimization procedure that takes place with the GINO model and spreadsheets. An application took place in an aquifer in Northern Greece, just on the border with the Former Yugoslavian Republic of Macedonia (FYROM). The phreatic aquifer was divided into 271 small square areas, 200 m wide. The total area of the aquifer was 10.84 km2. The time increment was equal to 1 month. Finally, the comparison of the two different optimization algorithms took place, concerning the pumping rates, the managed head distribution and the optimum pumping cost.
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PUGLIESE, A., and R. ROSÀ. "Effect of host populations on the intensity of ticks and the prevalence of tick-borne pathogens: how to interpret the results of deer exclosure experiments." Parasitology 135, no. 13 (April 28, 2008): 1531–44. http://dx.doi.org/10.1017/s003118200800036x.
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SUMMARYDeer are important blood hosts for feeding Ixodes ricinus ticks but they do not support transmission of many tick-borne pathogens, so acting as dead-end transmission hosts. Mathematical models show their role as tick amplifiers, but also suggest that they dilute pathogen transmission, thus reducing infection prevalence. Empirical evidence for this is conflicting: experimental plots with deer removal (i.e. deer exclosures) show that the effect depends on the size of the exclosure. Here we present simulations of dynamic models that take into account different tick stages, and several host species (e.g. rodents) that may move to and from deer exclosures; models were calibrated with respect to Ixodes ricinus ticks and tick-borne encephalitis (TBE) in Trentino (northern Italy). Results show that in small exclosures, the density of rodent-feeding ticks may be higher inside than outside, whereas in large exclosures, a reduction of such tick density may be reached. Similarly, TBE prevalence in rodents decreases in large exclosures and may be slightly higher in small exclosures than outside them. The density of infected questing nymphs inside small exclosures can be much higher, in our numerical example almost twice as large as that outside, leading to potential TBE infection risk hotspots.
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Kupar, Yu Yu, B. V. Dziubetsky, V. Yu Cherchel, and M. S. Olkhovik. "Determination of the optimal heterotic model of mid-ripening maize hybrids in the Northern Steppe of Ukraine." Scientific Journal Grain Crops 6, no. 1 (August 15, 2022): 5–14. http://dx.doi.org/10.31867/2523-4544/0201.
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Topicality. Currently, we can use more effectively the initial material of the working collection due to targeting certain heterosis models. Information about the advantages of different heterotic models in certain cultivation areas makes it easier to search for successful combinations and the selection of promising initial material. Issues. Тo identify of the most promising heterotic models of maize hybrids developed with using lines of different genetic plasms, which characterized by high yields and low grain moisture content compared to standard hybrids adapted to cultivation in the Northern Steppe. Aim. To determine the economic value of maize hybrids developed with using different germplasm lines and the most promising heterotic models for each genoplasm group. To investigate how the plant growing conditions influence on economic valuable indicators of hybrids depending on their genetic origin. Materials and Methods. Visual Method was used for phenological observations; Field and Laboratory Method was used to determine of morphobiological characteristics of plants; Measuring Weight Method – to determine the plant yield and metric characteristics; Mathematical and Statistical Method – to determine the reliability of results, the trait variability indicators, correlation dependence of traits; Analysis of Variance (ANOVA); comprehensive assessment of morphobiological and economically valuable characteristics of inbred lines and hybrids based on different genetic plasms. Results. It was found that testcrosses based on the Lancaster x Iodent model were the most stable by grain yield. However, in the average of three years of research, the highest average level (6.31 t/ha) was recorded in Mixed x Lancaster testcrosses. It was selected testcrosses with a higher grain yield compared to standard hybrids, such as DK3044xDK315, DK3151xDK4454, DK3151xDK3155 and DK365xDK6356 which had a yield of 8.0; 7.59; 7.18; 7.17 t/ha, respectively. We observed the best ratio of yield to grain moisture content (harvest index RH/M) in hybrid combinations of Lancaster x Mixed. Conclusions. It was determined the best testcrosses according to the ratio of yield to grain moisture content: DK315CxDK3821 (Mixed x BSSS) – 0.51; DK633/325xDK365 (Mixed x Iodent) – 0.51; DK365xDK6356 (Iodent x Lancaster) – 0.51; DK3044xDK315 (Lancaster x Mixed) – 0.56; DK3151xDK3155 (BSSS x Mixed) – 0.55; DK633/325xDK3155 (Lancaster x Mixed), based on which are developing the mid-ripening maize hybrids adapted to Steppe zone of Ukraine. Key words: maize, hybrid, line, germplasm, heterotic model, testcross, grain yield and moisture content at harvesting.
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Issayeva, Lyudmila, Kuanysh Togizov, Agata Duczmal-Czernikiewicz, Madina Kurmangazhina, and Daulet Muratkhanov. "Ore-controlling factors as the basis for singling out the prospective areas within the Syrymbet rare-metal deposit, Northern Kazakhstan." Mining of Mineral Deposits 16, no. 2 (June 30, 2022): 14–21. http://dx.doi.org/10.33271/mining16.02.014.
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Purpose is prediction of the prospective areas within the Syrymbet deposit basing on the systematization and complementing of the ore-controlling factors of ore localization and predictive-prospecting criteria. Methods. The methodology of carrying out the research in terms of the indicated problem involves complex application of empiric, theoretical, and logical techniques of a general-purpose method of scientific knowledge. To model the ore bodies and distribution of ore content in them in the 3D format, the computer modelling (GIS-Micromine) methods were used; 2D modelling of a temperature field of the ore-bearing Syrymbet mass involved methods of mathematical modelling (Maple 10). The main conclusions were drawn by means of analysis and synthesis of the results obtained by the indicated methods. Findings.. The ore-controlling factors of the localization of rare metal ores were systematized and complemented by synthesizing the results of the analysis of 3D models of the deposit under consideration with the visualization of ore component contents within the ore bodies and their 2D sections in terms of the survey profiles where spatial distribution of tin content in the vertical section of this deposit was obtained. The factors were also updated by analyzing the thermodynamic conditions of the formation of ore stockworks where temperature conditions of the enclosing media in the area of ore formation were considered along with the intervals of the ore deposition temperatures. Originality. The results of scientific studies (computer and mathematical modelling) based on the empiric geological data helped solve not only the problems of ore formation theory but also the practical tasks concerning the improvement of methods for predicting the prospective areas within the deposit. Practical implications. The methodology of scientific study dealing with systematization of ore-controlling factors can be also used for other endogenous ore objects.
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Adetunde, I. A. "The Mathematical Models of the Dynamical Behaviour of Tuberculosis Disease in the Upper East Region of the Northern Part of Ghana: A Case Study of Bawku." Current Research in Tuberculosis 1, no. 1 (December 15, 2008): 15–20. http://dx.doi.org/10.3923/crt.2009.15.20.
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Lydeamore, M. J., P. T. Campbell, W. Cuningham, R. M. Andrews, T. Kearns, D. Clucas, R. Gundjirryirr Dhurrkay, et al. "Calculation of the age of the first infection for skin sores and scabies in five remote communities in northern Australia." Epidemiology and Infection 146, no. 9 (May 8, 2018): 1194–201. http://dx.doi.org/10.1017/s0950268818001061.
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AbstractPrevalence of skin sores and scabies in remote Australian Aboriginal communities remains unacceptably high, with Group AStreptococcus(GAS) the dominant pathogen. We aim to better understand the drivers of GAS transmission using mathematical models. To estimate the force of infection, we quantified the age of first skin sores and scabies infection by pooling historical data from three studies conducted across five remote Aboriginal communities for children born between 2001 and 2005. We estimated the age of the first infection using the Kaplan–Meier estimator; parametric exponential mixture model; and Cox proportional hazards. For skin sores, the mean age of the first infection was approximately 10 months and the median was 7 months, with some heterogeneity in median observed by the community. For scabies, the mean age of the first infection was approximately 9 months and the median was 8 months, with significant heterogeneity by the community and an enhanced risk for children born between October and December. The young age of the first infection with skin sores and scabies reflects the high disease burden in these communities.
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Ravazzani, Giovanni, Chiara Corbari, Alessandro Ceppi, Mouna Feki, Marco Mancini, Fabrizio Ferrari, Roberta Gianfreda, et al. "From (cyber)space to ground: new technologies for smart farming." Hydrology Research 48, no. 3 (December 5, 2016): 656–72. http://dx.doi.org/10.2166/nh.2016.112.
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Increased water demand and climate change impacts have recently enhanced the need to improve water resources management, even in those areas which traditionally have an abundant supply of water, such as the Po Valley in northern Italy. The highest consumption of water is devoted to irrigation for agricultural production, and so it is in this area that efforts have to be focused to study possible interventions. Meeting and optimizing the consumption of water for irrigation also means making more resources available for drinking water and industrial use, and maintaining an optimal state of the environment. In this study we show the effectiveness of the combined use of numerical weather predictions and hydrological modelling to forecast soil moisture and crop water requirement in order to optimize irrigation scheduling. This system combines state of the art mathematical models and new technologies for environmental monitoring, merging ground observed data with Earth observations from space and unconventional information from the cyberspace through crowdsourcing.
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Grenfell, B. T., G. Smith, and R. M. Anderson. "Maximum-likelihood estimates of the mortality and migration rates of the infective larvae of Ostertagia ostertagi and Cooperia oncophora." Parasitology 92, no. 3 (June 1986): 643–52. http://dx.doi.org/10.1017/s0031182000065501.
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SUMMARYWe present an analysis of the survival and migration rates of the infective (L3) stages of Oslertagia ostertagi and Cooperia oncophora. Although the majority of laboratory studies show that the survival of the L3 stage depends upon temperature, moisture and the age of the larvae, a simple mathematical model of larval demography, in which their mortality and migration rates are held constant, provides as good agreement between observed and predicted larval counts as models in which these rate processes are made explicit functions of larval age and microclimate. Maximum-likelihood estimates of larval mortality rates in the faeces and on the herbage are 0·0284/day and 0·00887/day respectively. The average migration rate from faeces to herbage under temperate Northern European conditions is estimated as 0·00884/day. Finally, we discuss the probable scale of L3 larval losses due to desiccation and lavage (active or passsive migration into the soil).
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Stevenson, David S. "Planetary mass, vegetation height and climate." International Journal of Astrobiology 18, no. 05 (January 7, 2019): 477–82. http://dx.doi.org/10.1017/s1473550418000484.
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AbstractThe maximum height trees can grow on Earth is around 122–130 m. The height is constrained by two factors: the availability of water, and where water is not limiting, the pressure available to drive the column of water along the xylem vessels against the pull of gravity (cohesion tension). In turn the height of trees impacts the biodiversity of the environment in a number of ways. On Earth the largest trees are found in maritime temperate environments along the Pacific Northwest coasts of northern California and southern Oregon. These forests provide a large number of secondary habitats for species and serve as moisture pumps that return significant volumes of water to the lower atmosphere. In this work, we apply simple mathematical rules to illustrate how super-terran planets will have significantly smaller trees, with concomitant effects on the habitability of the planet. We also consider the impact of varying tree height on climate models.
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Polishchuk, S. S., O. O. Kotsyura, M. O. Dmitriev, V. O. Orlovskiy, and M. V. Popov. "Correlations of linear sizes of molars with cephalometric indicators of practically healthy men of the northern region of Ukraine." Reports of Morphology 26, no. 1 (May 22, 2020): 37–47. http://dx.doi.org/10.31393/morphology-journal-2020-26(1)-06.
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The question of the relationship between the metric characteristics of cranial structures and odontometric parameters, and the possibility of building models based on them, which can later find their practical application in dental practice, remain a pressing problem of modern medical science. The purpose of the study is to establish the features of the relationship between the linear dimensions of molars with the cephalometric parameters of the brain and facial skull of practically healthy men in the northern region of Ukraine. 32 practically healthy residents of the northern region of Ukraine (from Kyiv, Zhytomyr, Sumy and Chernihiv regions) underwent computed tomography followed by odontometry of molars and cephalometry. The correlations between odontometric and cephalometric parameters were assessed using Spearman’s nonparametric statistics in the licensed package “Statistica 6.1”. The peculiarities of the correlations of the studied characteristics of molars with the indicators of the cerebral skull are established – multiple, only direct reliable (r = 0.35-0.57) and unreliable (r = 0.30-0.35) average correlation force (18.7% on the upper jaw, of which the relative majority with vestibular-lingual and mesio-distal dimensions and 24.1% on the lower jaw, of which the relative majority with the height of the teeth, their crowns and the length of the tooth roots); as well as with the indicators of the facial skull – mostly direct reliable (r = 0.35-0.51) and unreliable medium strength (r = 0.30-0.37) correlations, in most cases of a single nature (6.0% on the upper jaw and 6.6% on the lower jaw, almost uniformly with the height of the teeth, their crowns, root length, vestibular-lingual and mesio-distal dimensions). The results of correlation analysis of craniofacial structures are necessary for the correct construction of mathematical models, which can later find their practical application in dental practice and forensic medicine.
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Denisov, D. V. "REFLECTION OF THE SAMKKHYA’S ONTOLOGICAL MODEL IN THE SPATIAL ORGANIZATION OF THE INDIAN VASTU-MANDAL." Izvestiya of the Samara Science Centre of the Russian Academy of Sciences. Social, Humanitarian, Medicobiological Sciences 23, no. 80 (2021): 60–67. http://dx.doi.org/10.37313/2413-9645-2021-23-80-60-67.
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The paper describes the regularity of the transition from the 25-element sankhya model to the 45-element structure of the vastu-mandalas. The author takes into account mathematical, structural and functional problems. The allocation of the first four ontological principles of Samkhya, as well as the sixth one, is similar to those of the Pythagorean Tetractys, but the fifth and the seventh to the ninth principles are expressed in each case by five-element groups, symbolizing the space of human life. The results obtained are applied to the analysis of cultural processes and geopolitical issues. The author describes the ontological foundations for identifying the "northern" and "southern" cultures and explains the inevitability of the confrontation between East and West. The analysis confirmed the characteristics of the space sectors, adopted in the ancient Indian picture of the world. Review of 40- / 45-element models includes the numerical model of Vastu-vidya in a general scientific context that has multiple temporal applications. An outstanding organization of vastumandalas allows to take into account general laws, analyze geopolitical processes, and perform functional zoning, combining the experience of antiquity and the achievements of modern times. The author considers that the analyzed models must be included into the methodological apparatus of the modern science.
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Peng, Yun, Wenyuan Wang, Xinglu Xu, Modi Chen, Xiangqun Song, and Xiangda Li. "A Simulation-Based Dynamic Programming Method for Interchange Scheduling of Port Collecting and Distributing Network." Journal of Advanced Transportation 2018 (August 6, 2018): 1–17. http://dx.doi.org/10.1155/2018/4805250.
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As one of the effective methods to reduce congestion, grade intersection has already been changed to interchange in port collecting and distributing network (PCDN) of many Chinese ports, since the first interchange was built in the PCDN of Dalian port in 1924. Due to the growing demand for port freight transportation, congestion in PCDN is becoming one of the inevitable problems that need to be solved. This paper addresses the best interchange scheduling multistage decision problem in PCDN at a network level. The main challenges are how to estimate the delay time and cope with high uncertainties in port network and PCDN. Therefore, a simulation-based dynamic programming (DP) model is proposed with the purpose of minimizing total cost in lifetime period by combining a DP model and two nested simulation models together. Two simulation models are built to figure out the delay cost in the optimization model, which cannot be calculated by mathematical analysis due to complex vehicle travel patterns and irregular traffic volume caused by random events, such as the arrival pattern of ships’, natural conditions, and storage period of cargos. Finally, a real project in northern China is presented as a case study. The proposed method can be applied in similar cases and can help solve analogous complicated multistage problems.
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Sun and Gao. "Short-Term Wind Speed Prediction Based on Variational Mode Decomposition and Linear–Nonlinear Combination Optimization Model." Energies 12, no. 12 (June 17, 2019): 2322. http://dx.doi.org/10.3390/en12122322.
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Wind power, one of renewable energy resources, is a fluctuating source of energy that prevents its further participation in the power market. To improve the stability of the wind power injected into the power grid, a short-term wind speed predicting model is proposed in this work, named VMD-P-(ARIMA, BP)-PSOLSSVM. In this model, variational mode decomposition (VMD) is combined with phase space reconstruction (P) as data processing method to determine intrinsic mode function (IMF) and its input–output matrix in the prediction model. Then, the linear model autoregressive integrated moving average model (ARIMA) and typical nonlinear model back propagation neural network (BP) are adopted to forecast each IMF separately and get the prediction of short-term wind speed by adding up the IMFs. In the final stage, particle swarm optimization least squares support vector machine (PSOLSSVM) uses the prediction results of the two separate models from previous step for the secondary prediction. For the proposed method, the PSOLSSVM employs different mathematical principles from ARIMA and BP separately, which overcome the shortcoming of using just single models. The proposed combined optimization model has been applied to two datasets with large fluctuations from a northern China wind farm to evaluate the performance. A performance comparison is conducted by comparing the error from the proposed method to six other models using single prediction techniques. The comparison result indicates the proposed combined optimization model can deliver more accurate and robust prediction than the other models; meanwhile, it means the power grid dispatching work can benefit from implementing the proposed predicting model in the system.
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Abtahi, Sayyed Mohammad, Laust Börsting Pedersen, Jochen Kamm, and Thomas Kalscheuer. "A new reference model for 3D inversion of airborne magnetic data in hilly terrain — A case study from northern Sweden." GEOPHYSICS 83, no. 1 (January 2018): B1—B12. http://dx.doi.org/10.1190/geo2016-0331.1.
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The inherent nonuniqueness in modeling magnetic data can be partly reduced by adding prior information, either as mathematical constructs or simply as bounds on magnetization obtained from laboratory measurements. If a good prior model can be used as a reference model, then the quality of estimated models through an inverse approach can be greatly improved. But even though data on magnetic properties of rocks might exist, their distribution may often be quite irregular on local and regional scales, so that it is difficult to define representative classes of rock types suitable for constraining geophysical models of magnetization. We have developed a new way of constructing a reference model that varies only laterally and is confined to the part of the terrain that lies above the lowest topography in the area. To obtain this model, several estimated 2D magnetization distributions were constructed by data inversion as a function of the iteration number. Then, a suitable 2D model of the magnetization in the topography was chosen as a starting point for constructing a 3D reference model by modifying it with a vertical decay such that its average source depth was the same for all horizontal positions. The average source depth of the reference model was chosen to satisfy the average source depth obtained from analyzing the radial power spectrum of the area studied. Finally, the measured magnetic data were inverted in three dimensions using the given reference model. For a selected reference model, shallow structures indicated a better overall correlation with large remanent magnetizations measured on rock samples from the area. Throughout the entire model, the direction of magnetization was allowed to vary freely. We found that the Euclidean norm of the estimated model was reduced compared with the case where the magnetization direction was fixed.
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Iglovsky, S. A., and V. V. Kriauciunas. "Anthrax cattle burials as a potential threat caused by changes in cryolite zones in the northern European part of Russia." Health Risk Analysis, no. 1 (March 2021): 108–14. http://dx.doi.org/10.21668/health.risk/2021.1.11.eng.
Full textAbstract:
Over recent years there have been registered anthrax cases among animals and people in Russia. Anthrax cattle burials remain a basic risk factor that causes epizootic deterioration. A lot of such burials do not correspond to sanitary-epidemiologic requirements especially those located in zones where long-term frozen rocks are now being developed in the northern European part of the country. Our research goal was to examine a situation with anthrax cattle burials in the chosen regions, especially bearing in mind climatic changes and changes in cryolite zones as well as to assess future prospects regarding them. It is especially vital for native people who live in tundra and breed their numerous deer herds there. To achieve the goal, several tasks were accomplished. First, we performed preliminary analysis of anthrax cattle burials distribution in the northern European part of the country and places that were unfavorable as per anthrax. Then, locations of such zones were compared with available data on contemporary development of the cryolite zone in the northern European part of the country. It was necessary to assess future changes in the cryolite zone and describe occurring problems related to anthrax cattle burials being widely spread there as well as to suggest possible ways to solve them. Over the last 50 years considerable spots in the cryolite zone have thawed through completely or partially, especially in an area close to the south border of frozen earth. It is important to know an actual situation with anthrax cattle burials given changing climatic conditions and to assess their future prospects. In order to prevent emergencies in zones where geocryological processes have been activated it is necessary to measure temperature on anthrax cattle burials territories, to assess geocryological threats, to create mathematical models for probable negative events occurrence, as well as to accomplish certain anti-epidemic, anti-epizootic, and preventive activities.
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Iglovsky, S. A., and V. V. Kriauciunas. "Anthrax cattle burials as a potential threat caused by changes in cryolite zones in the northern European part of Russia." Health Risk Analysis, no. 1 (March 2021): 108–14. http://dx.doi.org/10.21668/health.risk/2021.1.11.
Full textAbstract:
Over recent years there have been registered anthrax cases among animals and people in Russia. Anthrax cattle burials remain a basic risk factor that causes epizootic deterioration. A lot of such burials do not correspond to sanitary-epidemiologic requirements especially those located in zones where long-term frozen rocks are now being developed in the northern European part of the country. Our research goal was to examine a situation with anthrax cattle burials in the chosen regions, especially bearing in mind climatic changes and changes in cryolite zones as well as to assess future prospects regarding them. It is especially vital for native people who live in tundra and breed their numerous deer herds there. To achieve the goal, several tasks were accomplished. First, we performed preliminary analysis of anthrax cattle burials distribution in the northern European part of the country and places that were unfavorable as per anthrax. Then, locations of such zones were compared with available data on contemporary development of the cryolite zone in the northern European part of the country. It was necessary to assess future changes in the cryolite zone and describe occurring problems related to anthrax cattle burials being widely spread there as well as to suggest possible ways to solve them. Over the last 50 years considerable spots in the cryolite zone have thawed through completely or partially, especially in an area close to the south border of frozen earth. It is important to know an actual situation with anthrax cattle burials given changing climatic conditions and to assess their future prospects. In order to prevent emergencies in zones where geocryological processes have been activated it is necessary to measure temperature on anthrax cattle burials territories, to assess geocryological threats, to create mathematical models for probable negative events occurrence, as well as to accomplish certain anti-epidemic, anti-epizootic, and preventive activities.
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Dahab, Mohamed Hassan, Abdalla N. O. Kheiry, and Montasir Ahmed Gafar Elfaki. "Effect of Hours of Use and Age in Years in Estimating Repair and Maintenance Costs for Two Sizes of Agricultural Tractors in Northern Sudan." Journal of Agronomy Research 4, no. 2 (October 16, 2021): 1–11. http://dx.doi.org/10.14302/issn.2639-3166.jar-21-3875.
Full textAbstract:
Repair and maintenance cost is considered as one of important items for machinery management and selection. The present study was carried out in Dongola area for tractor repair and maintenance costs estimation. The data was collected from records of Elshimalya Company for Agricultural Inputs. Forty four tractors rep resenting two sizes of tractors, 75hp and 150hp used in the area were selected for this study. Based on the data collected, regression correlation analysis was carried out and mathematical models were derived to predict the accumulated repair and maintenance (R and M) costs as percent of purchase price in relation to accumulated hours of use and age (years) for each tractor size, and also for the two sizes collectively. Five model forms (linear, logarithmic, polynomial, power and exponential) were derived and the power function was found the best fit to explain the relation. The accumulated Rand M costs as percent of purchase price (Y) was increased as the accumulated hours of use (x) and age (g) of the tractor in years were increased. A high correlation was found between the accumulated R and M cost and both accumulated hours of use and tractor age in years (Average R2 = 0.93).
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Katarov, Vasily, Vladimir Syunev, and Gennady Kolesnikov. "Analytical Model for the Load-Bearing Capacity Analysis of Winter Forest Roads: Experiment and Estimation." Forests 13, no. 10 (September 21, 2022): 1538. http://dx.doi.org/10.3390/f13101538.
Full textAbstract:
In northern forests, winter is the preferred time for logging operations, since, when wet soils freeze, their strength increases, which ensures a high load-bearing capacity of winter forest roads and reduces the cost of forestry work by increasing the load on forestry equipment, including when driving through frozen lowlands. The present article analyzes frozen loamy–sandy soil, which, at subzero temperatures, behaves like a brittle material with a sufficiently high, but limited, strength. Well-known models commonly use empirical parameters, correlations, and numerical methods to estimate the strength of such materials. An analytical model of the full load–displacement curve would reduce the number of necessary calculations and increase the ability to predict the bearing capacity of winter forest roads. However, there are few of these models. Such models were developed, as a rule, to study stress–strain in concrete and rocks, meaning that researchers have to recalculate the load into stress and displacement into deformation, which is not always simple. This work aimed at theoretically justifying a new analytical model for quantifying the bearing capacity of winter forest roads and assessing the adequacy of the model by comparing it with experimental data. To achieve this purpose, the concepts of fracture mechanics and methods of mathematical modeling were used. The model was verified using experimental data, and model examples for determining the peak load were provided. Prospects for development of the research topic were also considered, taking into account new developments in forest road monitoring for logging management.
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Pavlov, A. V. "Subauroral red arcs as a conjugate phenomenon: comparison of OV1-10 satellite data with numerical calculations." Annales Geophysicae 15, no. 8 (August 31, 1997): 984–98. http://dx.doi.org/10.1007/s00585-997-0984-3.
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Abstract. This study compares the OV1-10 satellite measurements of the integral airglow intensities at 630 nm in the SAR arc regions observed in the northern and southern hemisphere as a conjugate phenomenon, with the model results obtained using the time-dependent one-dimensional mathematical model of the Earth ionosphere and plasmasphere (the IZMIRAN model) during the geomagnetic storm of the period 15–17 February 1967. The major enhancements to the IZMIRAN model developed in this study are the inclusion of He+ ions (three major ions: O+, H+, and He+, and three ion temperatures), the updated photochemistry and energy balance equations for ions and electrons, the diffusion of NO+ and O2+ ions and O(1D) and the revised electron cooling rates arising from their collisions with unexcited N2, O2 molecules and N2 molecules at the first vibrational level. The updated model includes the option to use the models of the Boltzmann or non-Boltzmann distributions of vibrationally excited molecular nitrogen. Deviations from the Boltzmann distribution for the first five vibrational levels of N2 were calculated. The calculated distribution is highly non-Boltzmann at vibrational levels v > 2 and leads to a decrease in the calculated electron density and integral intensity at 630 nm in the northern and southern hemispheres in comparison with the electron density and integral intensity calculated using the Boltzmann vibrational distribution of N2. It is found that the intensity at 630 nm is very sensitive to the oxygen number densities. Good agreement between the modelled and measured intensities is obtained provided that at all altitudes of the southern hemisphere a reduction of about factor 1.35 in MSIS-86 atomic oxygen densities is included in the IZMIRAN model with the non-Boltzmann vibrational distribution of N2. The effect of using of the O(1D) diffusion results in the decrease of 4–6% in the calculated integral intensity of the northern hemisphere and 7–13% in the calculated integral intensity of the southern hemisphere. It is found that the modelled intensities of the southern hemisphere are more sensitive to the assumed values of the rate coefficients of O+(4S) ions with the vibrationally excited nitrogen molecules and quenching of O+(2D) by atomic oxygen than the modelled intensities of the northern hemisphere.
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Pagliari, D., and L. Pinto. "USE OF FISHEYE PARROT BEBOP 2 IMAGES FOR 3D MODELLING USING COMMERCIAL PHOTOGRAMMETRIC SOFTWARE." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2 (May 30, 2018): 813–20. http://dx.doi.org/10.5194/isprs-archives-xlii-2-813-2018.
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Fisheye camera installed on-board mass market UAS are becoming very popular and it is more and more frequent the use of such platforms for photogrammetric purposes. The interest of wide-angles images for 3D modelling is confirmed by the introduction of fisheye models in several commercial software packages. The paper exploits the different mathematical models implemented in the most famous commercial photogrammetric software packages, highlighting the different processing pipelines and analysing the achievable results in terms of checkpoint residuals, as well as the quality of the delivered 3D point clouds. A two-step approach based on the creation of undistorted images has been tested too. An experimental test has been carried out using a Parrot Bebop 2 UAS by performing a flight over an historical complex located near Piacenza (Northern Italy), which is characterized by the simultaneous presence of horizontal, vertical and oblique surfaces. Different flight configurations have been tested to evaluate the potentiality and possible drawbacks of the previously mentioned UAS platform.<br> Results confirmed that the fisheye images acquired with the Parrot Bebop 2 are suitable for 3D modelling, ensuring accuracies of the photogrammetric blocks of the order of the GSD (about 0.05&thinsp;m normal to the optic axis in case of a flight height equal to 35&thinsp;m). The generated point clouds have been compared to a reference scan, acquired by means of a MS60 MultiStation, resulting in differences below 0.05 in all directions.