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1

An empirical model of rainfall intensity as a function of rainfall duration and probability of occurrence

Harisuseno Donny, Prasetyorini Linda, Fidari Jadfan S., Chandrasasi Dian

Journal of Water and Land Development

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2023

|

no. 56

182--193

EN

Rainfall is one of the main components of the hydrologic cycle; thus, the availability of accurate rainfall data is fundamental for designing and operating water resources systems and infrastructure. This study aims to develop an empirical model of rainfall intensity (It,p) as a function of its probability (p) and duration (t). In 1999-2020, data on the hourly duration of rainfall were collected from automatic rainfall recorder (ARR) gauges. The empirical model has been developed using a statistical approach based on duration (t) and probability (p), and subsequently they have been validated with those obtained from ARR data. The resulting model demonstrates good performance compared with other empirical formulas (Sherman and Ishiguro) as indicated by the percent bias (PBIAS) values (2.35-3.17), ratio of the RMSE (root mean square error) between simulated and observed values to the standard deviation of the observations (RSR, 0.028-0.031), Nash-Sutcliffe efficiency (NSE, 0.905-0.996), and index of agreement (d, 0.96-0.98) which classified in the rating of “very good” in model performance. The reliability of the estimated intensity based on the empirical model shows a tendency to decrease as duration (t) increases, and a good accuracy mainly for the rainfall intensity for shorter periods (1-, 2-, and 3-hours), whereas low accuracy for long rainfall periods. The study found that the empirical model exhibits a reliable estimate for rainfall intensity with small recurrence intervals (Tr) 2-, 5-, 10-, and a 20-year interval and for a shorter duration (t). Validation results confirm that the rainfall intensity model shows good performance; thus, it could be used as a reliable instrument to estimate rainfall intensity in the study area.

2

Size-dependent model to determine the effects of operational parameters on the performance of the Falcon concentrator

Aydogan Namik Atakan, Kademli Murat

Archives of Mining Sciences

|

2023

|

Vol. 68, no. 3

495--505

EN

The present study modelled the effects of operational parameters on the performance of the Falcon concentrator. For this purpose, the Falcon L40 concentrator was tested in narrow particle-size fractions (−600 + 425 μm, −425 + 300 μm, −300 + 212 μm, −212 + 150 μm, −150 + 106 μm, and −106 + 75 μm) at different washing water pressures and artificial gravity forces generated by a spinning bowl. The test samples were prepared artificially, comprising 2% magnetite (Fe3O4) and 98% calcite (CaCO3) by weight. The recovery and grade values of the 60 experimental conditions were investigated and compared for different operational parameters, including particle-size distributions, water pressures, and artificial gravity forces. Two empirical models were developed using non-linear regression analysis to indicate the effects of the operating parameter of the Falcon concentrator on its recovery and grade values. The operational parameters were found to impact the separation performance considerably. Therefore, the Falcon concentrator should operate under optimum conditions, which can be easily predicted using these models, to achieve improved recovery and grade values.

3

Rheological Properties of DNAN/HMX Melt-cast Explosives : Maximum Packing Density Calculation and Modified Viscosity Model

Meng Jun-jiong, Luo Yi-ming, Wang Wei, Jiang Qiu-li, Wang Hong-xing, Miao Fei-chao

Central European Journal of Energetic Materials

|

2022

|

Vol. 19, no. 3

326--359

EN

The study of suspensions with high solid content and low viscosity has become a very active topic for melt-cast explosives, for both research and industry. Previous studies have described how the viscosity of high-solid-content suspensions can be decreased by optimizing the grade ratio, that is, increasing the particle packing density. This paper numerically simulates the maximum packing density (Φm) for different grade ratios at which the suspension viscosity approaches infinity, using the overlapping discrete element cluster method. According to this method, the shape of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) particles was modeled as a group of overlapping, rigidly connected hard spheres. The results showed that the numerical simulation value can be used as the real value of Φm for any grade ratio in engineering applications. The rheological properties of 2,4-dinitroanisole (DNAN)/HMX suspensions with various grade ratios of three HMX samples with different d50 values were investigated using a rotational viscometer over a range of mass solids content (ϕ = 20-75 wt.%) in the shear rate range of 0.1-100 s⁻¹. An empirical model incorporating the reduced solid content (Φ, equal to ϕ divided by Φm) and shear rate (γ) was modified to predict the relative viscosity of DNAN/HMX suspensions. This modified model has a strong correlation with the experimental data and can be used to accurately predict the viscosity of DNAN/HMX suspensions. In addition, the applicability of different classical models to DNAN/HMX suspensions is discussed.

4

Improving the Quality of Anaerobically-Pretreated Palm Oil Mill Effluent Using Electrocoagulation

Sailah Illah, Reyhanto Fathan, Puspaningrum Tyara, Romli Muhammad, Suprihatin Suprihatin, Indrasti Nastiti Siswi

Journal of Ecological Engineering

|

2021

|

Vol. 22, nr 1

112--124

EN

The palm oil extraction process generates large amounts of effluents with very high concentrations of pollutants, even though they are subjected to anaerobic pretreatment. Further treatment is needed in order to ensure that the effluent is safe for disposal or reuse. This work was conducted to evaluate the performance of an electrocoagulation process in removing pollutants from the anaerobically-pretreated palm oil mill effluent. A 1000 ml beaker glass equipped with a magnetic stirrer was used as an electrocoagulation reactor with four plates of aluminum electrode @ 12×2 cm and an effective area of 0.1 m2 arranged in a bipolar configuration. The experiments run in a batch mode were carried out at various voltage levels and contact times, namely 10, 15, and 20 V for 15, 30, 45 and 60 min. The level of pollutant removal and electrical energy consumption were determined. The electrocoagulation process at 15 V for 30 min produced the highest level of pollutant removal for TSS, turbidity, color, COD, and BOD5, i.e. 90%, 86%, 93%, 87%, and 97%, respectively. The estimated operating costs for these process conditions are 1.48 USD/m3. A second order empirical model was developed to describe the TSS removal in the POME electrocoagulation process. The electrocoagulation with aluminum electrodes can significantly reduce various types of pollutants of anaerobically-pretreated POME, such as TSS, turbidity, color, COD, and BOD5. The estimated cost of EC operation is cheaper than the chemical coagulation process.

5

Experimental Verification of Standard Recommendations for Estimating the Load-carrying Capacity of Undercut Anchors in Rock Material

Jonak Józef, Karpiński Robert, Siegmund Michał, Machrowska Anna, Prostański Dariusz

Advances in Science and Technology. Research Journal

|

2021

|

Vol. 15, no 1

230--244

EN

The recommendations put forward in the International Standards for anchorage in concrete concerning the assessment of the load-carrying capacity of anchors (the pull-out force) embedded in natural rock material were verified. Regarding the predicted extent of surface failure we have shown, in earlier studies, substantial discrepancies between the strength test results for anchorages in the rock mass and the established standard recommendations for anchorages in concrete. As regards the industrial practice and the goals of the reported project, simplified calculation procedures that will facilitate the selection of optimal configurations for the layout of anchor holes, while being computationally effective and applicable under the industry-specific conditions are sought.

6

Computational intelligence for predicting biological effects of drug absorption in lungs

Pacławski Adam, Szlęk Jakub, Mendyk Aleksander

Computer Science

|

2019

|

Vol. 20 (1)

99--121

EN

Recently, the lungs have been extensively examined as a route for delivering drugs (active pharmaceutical ingredients, APIs) into the bloodstream; this is mainly due to the possibility of the noninvasive administration of macromolecules such as proteins and peptides. The absorption mechanisms of chemical compounds in the lungs are still not fully understood, which makes pulmonary formulation composition development challenging. This manuscript presents the development of an empirical model capable of predicting the excipients’ influence on the absorption of drugs in the lungs. Due to the complexity of the problem and the not-fully-understood mechanisms of absorption, computational intelligence tools were applied. As a result, a mathematical formula was established and analyzed. The normalized root-mean-squared error (NRMSE) and R2 of the model were 4.57%, and 0.83, respectively. The presented approach is beneficial both practically by developing an in silico predictive model and theoretically by gaining knowledge of the influence of APIs and excipient structure on absorption in the lungs.

7

Determination of "mi" in the Hoek–Brown failure criterion of rock

Arshadnejad S.

Mining Science

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2018

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Vol. 25

111--127

EN

The mi is an important parameter in the use of the Hoek–Brown failure criterion. It can be estimated using a triaxial compressive strength test but in many projects there is no actual test result for the parameter. An estimation of mi comes from a reference table giving a constant value. Elsewhere some empirical equations for the value were suggested in the 1990s. Applying these equations is limited use since they are available for a few rock types and the equations are based on just uniaxial compressive strength tests of rock. In this research rocks were divided into three categories (Igneous, Sedimentary and Metamorphic) and three empirical formulas are suggested for the categories based on uniaxial compressive strength (σci) and tensile strength (σt) of rocks by nonlinear regression. The equations have been obtained by a combination of the two independent parameters and the trial and error method was used to find the equations with the highest correlation coefficient. The data base uses data from many original international research projects and much data from Iranian tunnelling projects. The models have a high level of accuracy and have been used to describe most rock types although the authors know that the technique can be improved using a new and larger collection of data in the future.

8

An Empirical Model for the Ionospheric Global Electron Content Storm-Time Response

Li S., Galas R., Ewert D., Peng J.

Acta Geophysica

|

2016

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Vol. 64, no. 1

253--269

EN

By analyzing the variations of global electron content (GEC) during geomagnetic storm events, the ratio “GEC/GECQT” is found to be closely correlated with geomagnetic Kp index and time weighted Dst index, where GECQT is the quiet time reference value. Moreover, the GEC/GECQT will decrease with the increase of the solar flux F10.7 index. Furthermore, we construct a linear model for storm-time response of GEC. Eighty-two storm events during 1999-2011 were utilized to calculate the model coefficients, and the performance of the model was tested using data of 8 storm events in 2012 by comparing the outputs of the model with the observed GEC values. Results suggest that the model can capture the characteristics of the GEC variation in response to magnetic storms. The component describing the solar activity influence shows a counteracting effect with the geomagnetic activity component; and the influence of Kp index causes an increase of GEC, while the time weighted Dst index causes a decrease of GEC.

9

Simulations of the properties of elongated hexagonal dodecahedron systems

Grima J. N., Caruana-Gauci R., Attard D., Gatt R.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

|

2014

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Vol. 18, No 2

117--135

EN

This study considers a 3D basic unit-cell proposed for auxetic and non-au xetic foams namely the elongated hexagonal dodecahedron deforming through changes in angle b etween its ligaments (idealised hinging model). This structure was studied in detail for the potential of exhibiting negative Poisson’s ratio and/or negative compressibility b y means of a method based on standard force-field molecular modelling technique, termed as Empiri cal Modelling Using Dummy Atoms ( EMUDA ). The mechanical properties obtained from this method were then compared to a previously published analytical model of this structure [Grima J N, CaruanaGauci R, Attard D, and Gatt R 2012, Proc. Roy. Soc. A 468 3121], and found to be in good agreement with each other. The results showed that this system can ex hibit zero Poisson’s ratios in one of its planes and positive or negative Poisson’s ratios in other plan es, depending on the geometry of the model. It was also shown that under certain conditions, ne gative linear and/or area compressibility was also exhibited.

10

Matematyczny opis zmian masy w procesie rehydratacji suszonych plasterków korzenia pietruszki

Górnicki K., Kaleta A., Zdroik K., Gulski M.

Postępy Techniki Przetwórstwa Spożywczego

|

2013

|

nr 2

50--53

PL

W artykule przedstawiono wyniki badań procesu rehydratacji suszonych plasterków korzenia pietruszki. Grubość plasterków wynosiła 6 mm, temperatura suszenia 60°C. Proces prowadzono w wodzie destylowanej (objętości 100, 200, 300, 400 i 500 cm3) o temperaturach 20, 40, 60, 80 i 100°C. Wyznaczano krotności przyrostu masy (stosunek masy rehydratowanego suszu do masy początkowej suszu). Do opisu procesu rehydratacji wykorzystano model empiryczny Singh-Kulshrestha (SK). Współczynniki modelu uzależniono od parametrów procesu rehydratacji.

EN

The rehydration of dried parsley root slices was studied. Samples were cut into 6 mm slices. Temperature of drying air equaled 60°C. The effect of initial distilled water volume (100, 200, 300, 400 and 500 cm3) and rehydration temperature (20, 40, 60, 80 and 100°C) on the rehydration characteristics of dried parsley root slices was investigated. The ratio of the mass of rehydrated dried slices to initial mass of dried slices was determined. The empirical Singh-Kulshrestha (SK) model was used to describe the rehydration process. The coefficients of the SK model were conditioned to the parameters of rehydration.

11

Development of the intelligent algorithm to control on-line bead height for robotic welding process

Son J. S., Kim I. S., Lee J. H., Park M.H., Jeon G.S.

Journal of Achievements in Materials and Manufacturing Engineering

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2013

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Vol. 58, nr 2

87--93

EN

Purpose: The demand to increase productivity and quality, the shortage of skilled labour and strict health and safety requirements finally led to the development of the robotic welding process to deal with many problems of the welded fabrication. Many techniques were developed to control process parameters to get the optimal bead geometry during welding process by minimizes their magnitude in the affected area. Design/methodology/approach: The development of thermo mechanical mechanism in some techniques is not fully understood. To solve this problem, we have carried out the sequential experiment based on a Taguchi method and identified the various problems that result from the robotic GMA welding process. Findings: To characterize the GMA welding process and establish guidelines for the most effective joint design. Also using multiple regression analysis with the help of a standard statistical package program, SPSS, on an IBM-compatible PC, a quadratic model has been developed for on-line control which studies the influence of process parameters on bead height and compares their influences on the bead height to see which one of process parameters is most affecting. Originality/value: This model developed has been employed the prediction of optimal process parameters and assisted in the generation of process control algorithms.

12

Empirical Model for Estimating the Actual LNAPL Thickness Based on the Hydraulic Conductivity

Deska J., Tkaczyńska A.

Ecological Chemistry and Engineering. A

|

2012

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Vol. 19, nr 7

787-794

EN

The actual thickness of lighter-than-water non-aqueous phase liquid (LNAPL) on the groundwater table is always different from the apparent thickness (measured in the monitoring well). There are several methods developed for estimating the actual LNAPL thickness on the base of the apparent thickness, but the results obtained with different formulas are inconsistent and (in many cases) very imprecise. The obtained results of laboratory investigations indicate that the appropriate model for estimating the actual thickness of light non-aqueous phase liquid should include the properties of soil and LNAPL. The investigations confirmed that the hydraulic conductivity is very important parameter in the case of homogeneous soils. On the base of the results the empirical model was developed. This model includes the hydraulic conductivity of soil and the density and dynamical viscosity of LNAPL. The results of the verification of developed model indicate that the calculated values corresponded in many cases with the values obtained during laboratory investigations.

PL

Rzeczywista miąższość lekkiej cieczy organicznej (LNAPL) na zwierciadle wody podziemnej zawsze różni się od miąższości zmierzonej w studni (tzw. miąższości pozornej), a różnica między nimi jest zależna od właściwości gruntu i LNAPL oraz od ilości cieczy organicznej na zwierciadle wody. Metody stosowane obecnie do ustalania rzeczywistej miąższości LNAPL na podstawie zmierzonej miąższości pozornej pozwalają na uzyskiwanie wyników bardzo rozbieżnych i w większości przypadków nieprecyzyjnych. Metody te są bardzo uproszczone, uwzględniają zbyt małą liczbę parametrów (jedynie właściwości gruntów lub jedynie właściwości LNAPL). Poza tym, poprawne ustalenie wartości niektórych parametrów uwzględnionych w metodach jest bardzo trudne, zarówno w warunkach laboratoryjnych, jak i terenowych. Na podstawie uzyskanych wyników badań laboratoryjnych ustalono, że poprawnie opracowany model obliczania rzeczywistej miąższości LNAPL powinien uwzględniać zarówno właściwości gruntu, jak i LNAPL. Ustalono, że w przypadku gruntów jednorodnych, bardzo równomiernie uziarnionych, jednym z ważniejszych parametrów jest współczynnik filtracji. Na podstawie analizy kluczowych parametrów wpływających na zależność między miąższością pozorną i rzeczywistą opracowano model empiryczny uwzględniający współczynnik filtracji gruntu oraz współczynnik lepkości dynamicznej LNAPL. Weryfikacja modelu potwierdziła, że w większości przypadków jego zastosowanie pozwoliło na uzyskanie wyników zbliżonych do ustalonych w warunkach laboratoryjnych.

13

Empiryczny model osiadania gruntu organicznego. Metoda badawcza i jej wyniki

Kopczyńska O.

Czasopismo Techniczne. Budownictwo

|

2011

|

R. 108, z. 3-B

175-186

PL

Rozwój ekonomiczny miasta Szczecina skutkuje zainteresowaniem inwestorów obszarem torfowym Międzyodrza. Celem głównym artykułu uwzględnienie właściwości reologicznych tego słabego gruntu w modelu obliczeniowym. W pracy zastosowano wstępne oszacowanie parametrów równania modelu Meyera, który został opracowany w roku 1990 w Katedrze Geotechniki Zachodniopomorskiego Uniwersytetu Technicznego w Szczecinie. Opisano empiryczny model Meyera i omówiono badania laboratoryjne próbek gruntu. Dokonano wstępnego określenia parametrów gruntu w równaniu uproszczonym krzywej podstawowej. Badaniom laboratoryjnym poddano dwie grupy próbek gruntu organicznego. Uzyskano charakterystyczne kształty krzywej osiadania, co potwierdziło wstępnie przyjęte założenia.

EN

The economical expansions of Szczecin determines the investors' interest of the peat areas of Międzyodrze. The main job of the article is to take the rheology properties of the weak organic soil into consideration in the model. The study applies to initial estimation of parameters of the equation of the Meyer's model which was developed in 1990 in the Cathedral of Geotechnics in the ZUT in Szczecin. There here was shortly described empirical model of Meyer and there were discussed laboratory researches of samples of the soil and there was made initial estimation of parameters of simplified equation of the elementary curve. There has been two groups of samples of the organic soil examined. There has been received the characteristic shape of the sedimentation curve, that proved the initial assumption.

14

Zróżnicowanie kosodrzewiny w Tatrach, w świetle badań teledetekcyjnych

Zwijacz-Kozica M.

Teledetekcja Środowiska

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2010

|

T. 44

1--61

EN

Dwarf mountain pine (Pinus mugo Turra) is the main component in the subalpine belt in the Tatra National Park, where the study was conducted. From the ecological point of view dwarf pine plays an important role in the sensitive mountainous area. Until now there were no studies focused on structure of dwarf pine community and there were also no attempts to work out methodology for detailed qualitative and quantitative description of dwarf pine. In this study for the first time it was aimed to prepare methodology of dwarf pine characterization and monitoring using hyperspectral data. Analysis involved processing of airborne and satellite images data and field measurements. Presented study evaluated linear predictive models between vegetation indices derived from radiometrically corrected air- borne imaging spectrometer ROSIS, spectral field and laboratory measurements and field measurements of dwarf pine biophysical variables (LAI, fAPAR). Narrow band vegetation indices were computed on the basis of all possible two-band combinations of set of vegetation indices (VI, NDVI, PVI, SAVI2, TSAVI). VI based on ROSIS wavebands 510 nm and 630 nm was linearly related to leaf area index (R2=0,48). VI and NDVI based on FieldSpec HH wavebands 886 nm and 518 nm performed better and were linearly related to LAI (R2=0,72). TSAVI based on ROSIS wavebands 658 nm and 570 nm was linearly related to the fraction of absorbed photosynthetically active radiation (R2=0,72). SAVI2 based on FieldSpec HH wavebands 747 nm and 703 nm was linearly related to fAPAR (R2=0,81). Analysed indices of vegetation condition were correlated (R2>0,90) with spectral vegetation indices based on FieldSpec Pro laboratory data. The study shows that for hyperspectral image data covering spectral region of visible light and near infrared, linear regression models can be applied to quantify LAI and fAPAR with satisfying accuracy. Models involving spectral information from sensors that have wider spectral range have better potential to linearly quantify biophysical vegetation parameters involving spectral vegetation indices. Vegetation indices that have the best relation to LAI and fAPAR were based on wavebands related to spectral features. It can be assumed that hyperspectral data contain information relevant to the estimation of vegetation biophysical parameters. In this study it was investigated if dwarf pine community differs spectrally within study site. To assess presence and extent of the spectral differentiation the set of field and laboratory spectral measurements were used. Reflectance curves were compared visually and using the statistical test. It was demonstrated that the majority of the studied dwarf pine plots have a characteristic signature. Parts of the electromagnetic spectrum which offer greatest information content for discriminating between and identifying dwarf pine spectral types were indicated. It was also examined if any of abiotic components of environment (altitude above sea level, aspect, slope, soil type, geology, global radiation and temperature) has an influence on the spatial distribution of LAI and fAPAR values. WMP (index of tie strength) and MP (tie strength) were used to assess an extent of the influence. It was found that neither of investigated abiotic factors affects LAI and fAPAR values.

15

Influence of the hydraulic conductivity of soil on the difference between apparent and actual thickness of LNAPL on the groundwater table

Deska I., Szewczyk A.

Proceedings of ECOpole

|

2009

|

Vol. 3, No. 2

289--294

EN

The actual thickness of lighter-than-water non-aqueous phase liquid (LNAPL) on the groundwater table is always different from the apparent thickness (measured in the monitoring well). There are several methods developed for estimating the actual LNAPL thickness on the base of the apparent thickness, but the results obtained with different formulas are inconsistent and (in many cases) very imprecise. The obtained results of laboratory investigations indicate that the appropriate model for estimating the actual thickness of light non-aqueous phase liquid should include the properties of soil and LNAPL. The investigations confirmed that the hydraulic conductivity is very important parameter in the case of homogeneous soils. On the base of the results the empirical model was developed. This model includes the hydraulic conductivity of soil and the density and dynamical viscosity of LNAPL. The results of the verification of developed model indicate that the calculated values corresponded in many cases with the values obtained during laboratory investigations.

PL

Rzeczywista miąższość lekkiej cieczy organicznej (LNAPL) na zwierciadle wody podziemnej zawsze różni się od miąższości zmierzonej w studni (tzw. miąższości pozornej), a różnica między nimi jest zależna od właściwości gruntu i LNAPL oraz od ilości cieczy organicznej na zwierciadle wody. Metody stosowane obecnie do ustalania rzeczywistej miąższości LNAPL na podstawie zmierzonej miąższości pozornej pozwalają na uzyskiwanie wyników bardzo rozbieżnych i w większości przypadków nieprecyzyjnych. Metody te są bardzo uproszczone, uwzględniają zbyt małą liczbę parametrów (jedynie właściwości gruntów lub jedynie właściwości LNAPL). Poza tym poprawne ustalenie wartości niektórych parametrów uwzględnionych w metodach jest bardzo trudne zarówno w warunkach laboratoryjnych, jak i terenowych. Na podstawie uzyskanych wyników badań laboratoryjnych ustalono, że poprawnie opracowany model obliczania rzeczywistej miąższości LNAPL powinien uwzględniać zarówno właściwości gruntu, jak i LNAPL. Ustalono, że w przypadku gruntów jednorodnych bardzo równomiernie uziarnionych jednym z ważniejszych parametrów jest współczynnik filtracji. Na podstawie analizy kluczowych parametrów wpływających na zależność między miąższością pozorną i rzeczywistą opracowano model empiryczny uwzględniający współczynnik filtracji gruntu oraz współczynnik lepkości dynamicznej LNAPL. Weryfikacja modelu potwierdziła, że w większości przypadków jego zastosowanie pozwoliło na uzyskanie wyników zbliżonych do ustalonych w warunkach laboratoryjnych.

16

Influence the ground permeability of LNAPL on the difference between apparent and actual free product thickness at the groundwater table

Deska I., Malina G.

Proceedings of ECOpole

|

2008

|

Vol. 2, No. 1

19--24

EN

In order to design the efficient recovery of lighter-than-water non-aqueous phase liquid (LNAPL) frorn the groundwater table, the data on real free product thickness should be provided. An appropnate model for estimating the free-product thickness was shown to include both: soil and LNAPL properties. The LNAPL ground permeability is an important parameter, which influences on the difference between apparent and actual thickness. This pararaeter depends on soil and LNAPL properties. The paper presents the developed empirical model for estimation of actual free product thickness that is based on the ground permeability and viscosity of LNAPL. The values calculated with use of proposed model fitted in many cases well the values obtained during laboratory irwestigations.

PL

W celu prawidłowego zaprojektowania operacji sczerpywania lekkich cieczy organicznych niemieszających się z wodą (LNAPL) ze zwierciadła wody podziemnej niezbędna jest znajomość ich rzeczywistej miąższości. Ustalono, że poprawny model pozwalający na wyznaczenie miąższości rzeczywistej na podstawie miąższości pozornej (zmierzonej w studni obserwacyjnej) powinien uwzględniać zarówno cechy gruntu, jak i parametry LNAPL. Bardzo ważnym parametrem wpływającym na różnicę między miąższością pozorną i rzeczywistą, który łączy w sobie te dwa elementy, jest przepuszczalność gruntu względem LNAPL.

17

Komputerowe wspomaganie projektowania procesów azotowania gazowego z wykorzystaniem i metod sztucznej inteligencji

Dobrodziej J., Ratajski J., Michalski J., Suszko T., Wojutyński J., Tacikowski J., Wach P.

Inżynieria Powierzchni

|

2007

|

nr 3

82-93

PL

W artykule przedstawiono modele do symulacji procesów obróbek powierzchniowych na przykładzie procesu azotowania gazowego. Modele składają się z: 1) heurystycznych modeli do określania składu atmosfery azotującej na podstawie zakładanego przebiegu zmian temperatury i potencjału azotowego podczas procesu, 2) sztucznej sieci neuronowej do przewidywania profili mikrotwardości dla danych parametrów procesu, 3) algorytmów ewolucyjnych do określania parametrów procesu dla danego profilu twardości. Osiągnięto bardzo dobre działanie modeli. Dla wygodnego posługiwania się modelami opracowano graficzny interfejs użytkownika (GUI). Opracowane modele cząstkowe są zintegrowane w jeden wspólny model. Przedstawione przykłady wykorzystania modelu dla optymalizacji parametrów procesu pokazują, że jest to wygodne i użyteczne narzędzie dla praktycznych zastosowań w inżynierii powierzchni.

EN

Models for simulation of processes of surface treatment have been presented in the article. Nitriding process has been used as an exemplar. The models consist of.o 1) heuristic models to define the composition of nitriding atmosphere on the base of the assumed course of the changes of the temperature and nitriding potential during the process, 2) artificial neural network to predict profiles of micro-hardness for given process parameters, 3) evolutionary algorithms to foresee the process parameters for the given profile of hardness. The models of very good performance were achieved. Graphical user interface (GUl) has been created for easy use of the models. Designed models are combined and integrated in software package that is built up on a modular fashion. The exemplars of the application of the models are given, to demonstrate that they are convenient and powerful tools in surface engineering.

18

Empiryczny model matematyczny procesów konwersji HC i NOx w reaktorze HC-SCR wykorzystującym platynę i złoto

Kruczyński S. W., Kwiatkowski M., Zieliński T.

Zeszyty Instytutu Pojazdów / Politechnika Warszawska

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2005

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z. 3/58

41--47

PL

W pracy przedstawiono sposoby matematycznego modelowania reaktorów katalitycznych. Przedstawiono zagadnienia występujące w tych procesach. W szczególności został omówiony model empiryczny. Przedstawiono sposób jego zastosowania do zamodelowania konwersji NO i HC w spalinach silnika o zapłonie samoczynnym na przykładzie katalizatora niskotemperaturowego Pt i wysokotemperaturowego Au. Oceniono dokładność i ograniczenia zastosowanej metody.

EN

This paper gives an overview about classification of catalytic converter modeling. An empirical model is shown in details. The aim of this article is to present results of modeling NO and HC conversion in the exhaust gases of diesel engines on low temperature catalyst Pt and high temperature catalyst Au.

19

Growth rate of Pseudocalanus spp. as a function of food concentration, body weight and temperature

Dzierzbicka-Głowacka L., Zieliński A.

Oceanological and Hydrobiological Studies

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2003

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Vol. 32, No. 4

171-197

EN

This paper does not report the results of original research; it is an analysis of data from the literature. The aim of this project was to develop quantitative expressions to describe the effects of food concentration, temperature and body weight on the growth rate of copepodid stages of Pseudocalanus spp. Calculations were done for two geographically separate populations of Pseudocalanus – one from Puget Sound (Washington, USA) and the other from the southern North Sea- based on experimental data from the literature (see Vidal 1980, Thompson 1982). The relationships between the growth rate of Pseudocalanus from Puget Sound and temperatures in the range of 8o-15.5oC, food concentration and body weights ranging from 1.5 to 10 ěgd.w. (case 1) and 0.51 to 3.7 ěgC (case 2) were determined, as were those for Pseudocalanus from the southern North Sea at a high food concentration and at temperatures ranging from 4o to 15oC. The results demonstrate that the maximum growth rate decreased as temperature fell and that it become less dependent on temperature at higher body weights. The critical food concentration for growth increased with body size proportionally more at high than at low temperatures. Slight differences in growth rate were also detected between the two species of Pseudocalanus.

20

Modelowanie empiryczne w procesie wczesnego ostrzegania i zapobiegania współczesnym konfliktom zbrojnym

Białoskórski R.

Zeszyty Naukowe AON

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2002

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nr 1(46)

52--75

EN

The interest in applying mathematical methods for social processes' calculations, analyses and research has been developing in the last few years. The article presents one of the contemporary directions to apply mathematical methods in the process of early warning against modern armed conflicts, based on empirical modelling developed by International Centre for Conflicts and Negotiations in Tbilisi. The theoretical assumptions of the empirical model were supported by a particular practical example that largely explains the idea of the problem under consideration without the necessity to have a broad knowledge in higher mathematics.