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1

Sensitivity analysis of the specific heat and thermal conductivity values on pore pressure and temperature distribution within embankment

Franczyk A.

Measurement Automation Monitoring

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2017

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Vol. 63, No. 3

86--89

EN

The paper presents the results of the sensitivity analysis of the variability of thermal conductivity and specific heat values on temperature field and pore pressure distribution during the flooding process simulation. The sensitivity analysis was carried out using data obtained from numerical modellings. During numerical modellings the simulation of flooding process included flooding and discharging the tank, with maximum water level equal to 3.0 m was performed. 2D model was realized using Fast Lagrangian Analysis of Continua (FLAC) 7.0 software, which is a two-dimensional explicit finite difference program for engineering mechanics computation. The results presented in this paper show that the sensitivity analysis method is powerful technique that can be used in detection of area within the embankment where the biggest impact on variability of thermal conductivity are presented. It may be helpful in selecting the best area for pore pressure and temperature sensors location.

2

Influence of initial water saturation in earthen levees on results of numerical modelling of infiltration processes

Dwornik M., Franczyk A., Leśniak A., Krawiec K.

Computer Science

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2017

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Vol. 18 (4)

413--427

EN

Levees in Poland are mostly earthen constructions. The stability of earthen levees depends largely on factors such as the construction material, meteorological conditions and natural elements. The influence of initial water saturation of pore space on levee stability is analysed in this paper. Analysis was performed using numerical modelling and water pore pressure results were compared against data obtained from sensors located in a levee. The numerical modelling shows the moderate influence of initial water level on distribution of water pore pressure during high water level.

3

Time reversal seismic source imaging using peak average power ratio (PAPR) parameter

Franczyk A., Leśniak A., Gwiżdż D.

Acta Geophysica

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2017

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Vol. 65, no. 2

299--308

EN

The time reversal method has become a standard technique for the location of seismic sources. It has been used both for acoustic and elastic numerical modelling and for 2D and 3D propagation models. Although there are many studies concerning its application to point sources, little so far has been done to generalise the time reversal method to the study of sequences of seismic events. The need to describe such processes better motivates the analysis presented in this paper. The synthetic time reversal imaging experiments presented in this work were conducted for sources with the same origin time as well as for the sources with a slight delay in origin time. For efficient visualisation of the seismic wave propagation and interference, a new coefficient—peak average power ratio—was introduced. The paper also presents a comparison of visualisation based on the proposed coefficient against a commonly used visualisation based on a maximum value.

4

Synteza bimetalicznego silseskwioksanowego kompleksu tytanu(IV) i jego polimerycznego odpowiednika oraz ich właściwości katalityczne w polimeryzacji olefin

Pochwała M., Białek M., Franczyk A., Czaja K., Marciniec B.

Polimery

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2016

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T. 61, nr 9

591--599

PL

Zsyntetyzowano, a następnie scharakteryzowano dwa tytanosilseskwioksany: nowy, nieznany dotąd z literatury, tetrachloroditytanosilseskwioksan (2) i jego polimeryczny odpowiednik (3). Zbadano właściwości katalityczne otrzymanych związków w polimeryzacji etylenu i 1-oktenu. Obydwa prekatalizatory, po aktywacji za pomocą Et2AlCl lub EtAlCl2, katalizują polimeryzację etylenu do polietylenu (PE) o małej masie molowej, która zmniejsza się zarówno ze wzrostem temperatury reakcji, jak i stosunku molowego Al:Ti. Kompleks (2) w połączeniu z metyloaluminoksanem lub związkami boru jest także aktywny w polimeryzacji 1-oktenu.

EN

The new compound, tetrachlorodititanasilsesquioxane (2) and its polymeric analogue (3) have been synthesized, characterized and used for the first time in ethylene and 1-octene polymerization. These precatalysts, activated by Et2AlCl and EtAlCl2, were found to be catalytically active in polymerization of ethylene. The resulting polyethylenes have rather low molecular weight, decreasing with an increase in both reaction temperature and molar ratio of Al:Ti. In the presence of methylaluminoxane or boron compounds, the complex (2) also promotes polymerization of 1-octene.

5

Analysis of stability levee during different flooding wave stages

Dwornik M., Franczyk A.

Geology, Geophysics and Environment

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2016

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Vol. 42, no. 1

67--68

EN

The stability of levee depends mainly on mechanical and hydromechanical properties of material used for its construction. The structural capacity of a system beyond the expected loads or actual loads is calculated to a variety of different underground structures such as slopes, retaining walls or tunnels. The stability of structure is often expressed by Factor of Stability (FoS) obtained by numerical modeling. In case of the stability analysis of the levee, the flooding process is limited to few scenarios of flooding waves. The first approach of determination of the most significant stages of flooding wave shape can be found in Dwornik et al. (2015). In this paper, the stability of earthen levee for different stages and flooding waves was calculated. Stability of the levee was described using Factor of Safety implemented in Itasca Flac 2D 7.0 software using the strength reduction procedure (Itasca 2011). It is applied by a strength reduction method, which reduces the shear strength of the material to bring the slope to a state of limiting equilibrium. The value of FoS bigger than 1.0 indicate the stable construction, whereas the value less than 1.0 should be interpreted as a possible unstable model (Itasca 2011). Numerical modeling presented in this paper was performed for 17 different schemes of flooding wave. All the schemas were slight modification of the flooding wave considered during the ISMOP project (www.ismop.pl, Mościcki et al. 2014). The analysis was conducted to the flooding wave described by the four stages: water level increasing, durability of the height water level, the pace of water level decreasing and durability of the stage between cycles of successive flooding waves. The increasing of the water level assumed in the numerical modeling varied from 0.1 m to 3.5 m in height. The high water level, assumed as a 3.5 m, was different for the individual scenario. The decreasing water level varied from 3.5 m to 0.1 m preceding the low water level assumed 0.1 m in height. Calculations show that levee is stable for all tested construction stages. The lowest FoS value was obtained after decreasing water level in the reservoir between levees. The slowest pace of decreasing water level was assumed, the higher value of FoS was obtain, which indicated better levee stability. The study was partly financed from the statutory research project No. 11.11.140.613 of the Department of Geoinformatics and Applied Computer Science, AGH University of Science and Technology and by the National Centre for Research and Development (NCBiR) in Poland, project PBS1/B9/18/2013 (no 180535).

6

A Big Data processing strategy for hybrid interpretation of flood embankment multisensor data

Chuchro M., Franczyk A., Dwornik M., Leśniak A.

Geology, Geophysics and Environment

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2016

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Vol. 42, no. 3

269--277

EN

The assessment of flood embankments is a key component of a country’s comprehensive flood protection. Proper and early information on the possible instability of a flood embankment can make it possible to take preventative action. The assessment method proposed by the ISMOP project is based on a strategy of processing huge data sets (Big Data). The detection of flood embankment anomalies can take two analysis paths. The first involves the computation of numerical models and comparing them with real data measured on a flood embankment. This is the path of model-driven analysis. The second solution is data-driven, meaning time series are analysed in order to detect deviations from average values. Flood embankments are assessed based on the results of model-driven and data-driven analyses and information from preprocessing. An alarm is triggered if a critical value is exceeded in one or both paths of analysis. Tests on synthetic data demonstrate the high efficiency of the chosen methods for assessing the state of flood embankments.

7

Poliuretany modyfikowane funkcjonalizowanym silseskwioksanem — synteza i właściwości

Pielichowski K., Jancia M., Hebda E., Pagacz J., Pielichowski J., Marciniec B., Franczyk A.

Polimery

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2013

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T. 58, nr 10

783--793

PL

Stosując dwuetapową (prepolimerową) metodę otrzymano segmentowe elastomery uretanowe z wbudowanym chemicznie reaktywnym nanonapełniaczem, którym był funkcjonalizowany poliedryczny oligosilseskwioksan (PDSPOSS). W ramach pierwszego etapu prowadzono poliaddycję w masie 4,4'-diizocyjanianu difenylometanu (MDI, segmenty sztywne) z wbudowanym już na tym etapie nanonapełniaczem oraz z glikolem polioksytetrametylenowym (PTMG, segmenty giętkie). Drugi etap polegał na przedłużaniu łańcucha tak otrzymanego prepolimeru izocyjanianowego za pomocą 1,4-butanodiolu (BD). Zsyntezowano w ten sposób szereg elastomerów uretanowych PUR/PDSPOSS o różnej zawartości PDSPOSS (0, 2, 4 lub 6 % mas.). Budowę chemiczną otrzymanych materiałów analizowano techniką ATR FT-IR. Za pomocą mikroskopu SEM sprzężonego z analizatorem rentgenowskim EDS oraz możliwością tzw. mappingu pokazano strukturę mikrodomenową elastomerów oraz dystrybucję cząsteczek PDSPOSS w elastomerze uretanowym. Właściwości termiczne otrzymanych materiałów badano za pomocą analizy TG i DSC. Na podstawie badań DSC stwierdzono wzrost temperatury zeszklenia segmentów sztywnych wraz ze wzrostem dodatku PDSPOSS. Właściwości termomechaniczne badano za pomocą metody DMA, a otrzymane wyniki świadczą o tym, że modyfikacja za pomocą PDSPOSS daje możliwości poprawy właściwości tłumiących nanohybrydowych elastomerów uretanowych. Badania wytrzymałościowe wykazały, iż dodatek PDSPOSS polepsza również właściwości mechaniczne takich elastomerów.

EN

Segmental urethane elastomers with built-in chemically reactive nanofiller (propanediolsiloxy-POSS) were prepared by a two-stage (prepolymer) method. The first stage involved bulk-polyaddition reaction of 4,4'-diphenylmethane diisocyanate (MDI, rigid segments) containing the incorporated POSS nanofiller, with poly(oxytetramethylene) glycol (PTMG, soft segments). In the next stage the chain of such prepared isocyanate prepolymer was extended with 1,4-butanediol (BD, soft segment). In this way a series of urethane elastomers containing different amounts (0, 2, 4, 6 wt. %) of POSS moieties was synthesized. The chemical structure of prepared materials was analysed by ATR FT-IR. Using SEM coupled with EDS and mapping capability, the structure of elastomer microdomains and distribution of PDSPOSS molecules in the urethane elastomer was shown. The thermal properties of the materials were characterized using TG and DSC methods. Based on DSC studies, an increase in the glass transition temperature of hard segments with an increase of PDSPOSS content (which may be related to oligosilsesquioxane moieties embedded in this phase) has been found. Thermomechanical properties were tested using DMA and the results show that modification with PDSPOSS gives a possibility to improve the damping properties of polyurethane nanohybrid elastomers. Strength tests have indicated that the addition of PDSPOSS results also in enhanced mechanical properties of polyurethane elastomers.

8

Parallel and distributed seismic wave-field modeling

Danek T., Franczyk A.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2004

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Vol. 8, No 4

573-581

EN

Elastic or acoustic wave-field modeling is an important part of seismic exploration. It can be used during the planning, processing and interpretation stages of seismic investigation. First attempts of using wave-field modeling were undertaken in the seventies by Alford, Kelly and others (Alford R M, Kelly K R and Boore D M 1974 Geophysics 39 (6) 834; Kelly K R, Ward R W, Treitel S and Alford R M 1976 Geophysics 41 2). These attempts were restricted by the limitations of computers at that time. Even now, computation for models of the standard exploration scale could last many hours, and many days in case of longer recording times. One of the best methods to overcome this disadvantage is parallelization of computations (Niccanna C and Bean C J 1997 Computers and Geosciences 23 (7) 771; Villareal A and Scales J A 1997 Computers in Physics 11 (4) 388). This paper presents the results of distributed parallelization of elastic and acoustic wave-field modeling based on a Parallel Virtual Machine.

9

Modelowania sejsmicznego pola falowego w środowisku rozproszonym z wykorzystaniem parallel Virtual Machine

Franczyk A., Leśniak A., Danek T.

Prace Naukowe Instytutu Górnictwa Politechniki Wrocławskiej. Konferencje

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2004

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Vol. 107, nr 39

135-143

PL

Modelowanie pola falowego za pomocą metody różnic skończonych jest powszechnie stosowaną techniką w naukach o Ziemi. Modelowania wymagają od środowiska obliczeniowego dużych zasobów pamięci i dużej szybkości, dlatego w ich realizacji wykorzystuje się głównie superkomputery. W obliczeniach wykorzystano pakiet PVM - Równoległej Maszyny Wirtualnej, środowiska oprogramowania do realizacji obliczeń równoległych. Zbudowano klaster ze stacji roboczych działających pod systemem operacyjnym Linux. W niniejszej pracy skupiono się na pomiarze czasu obliczeń równoległych dla zmiennej liczby komputerów wchodzących w skład Maszyny Wirtualnej i na pomiarze szybkości obliczeń w zależności od sposobu dekompozycji tego samego zadania obliczeniowego.

EN

Finite - difference modeling of wave propagation is useful technique in geosciences. However the size of the model limited their application to supercomputers. In this paper we present an alternative which is inexpensive. Parallel configuration can be obtain for example by clustering a set of PCs workstations. We use the parallel Virtual Machine (PVM) - a public domain software package to create computer system made from network of PCs running the Linux operatin system In this paper are presented serial and parallel wall - clock times over changing numbers of machines in cluster and various domain decomposition schame.

10

Analiza wydajności klastrów PVM w modelowaniu pola falowego

Franczyk A.

Prace Instytutu Nafty i Gazu

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2004

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nr 130

299--303

PL

Modelowanie pola falowego za pomocą metody różnic skończonych jest powszechnie stosowaną techniką w naukach o Ziemi. Modelowania wymagają od środowiska obliczeniowego dużych zasobów pamięci i dużej szybkości, dlatego w ich realizacji wykorzystuje się głównie superkomputery. W obliczeniach wykorzystano klaster zbudowany ze stacji roboczych działających pod systemem operacyjnym Linux i pakiet PVM — środowisko oprogramowania do realizacji obliczeń równoległych. Mierzono czas obliczeń dla zmiennej liczby komputerów wchodzących w skład Maszyny Wirtualnej, określano przyspieszenia i efektywności zastosowanego środowiska rozproszonego, w zależności od sposobu dekompozycji tego samego zadania obliczeniowego.

EN

Finite — difference modeling of wave propagation is useful technique in geosciences. However the size of the model limited their application to supercomputers. In this paper we present an alternative which is inexpensive. Parallel configuration can be obtain for example by clustering a set of PCs workstations. We use the parallel Virinal Machine (PVM) — a public domain software package to create computer system made from network of PCs running the Linux operating system.ln this paper are presented serial and parallel wall — clock times, speed up and efficiency over changing numbers of machines in cluster and various domain decomposition scheme.