Wyniki wyszukiwania - BazTech

1

Influence of the Extrusion Cavity Shape on the Ultimate Extrusion Force Value During Pellet Extrusion Through Multiple-Cavity Dies

Górecki Jan, Łykowski Wiktor, Gumeni Maria

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 1

118--128

EN

The article describes the results of experimental research that allowed us to compare the influence of the forming channel shape and its length on the limit value of the force occurring in the process of extruding crystallized carbon dioxide using multi-channel dies. To carry out the research, the authors adopted a method described in the literature, which allows for experimenting using a sublimating material under normal conditions, at a temperature of -78.4°C. Analysis of variance was used for the statistical analysis of the experiment results, which allowed to determine the level of statistical significance of differences between individual populations. Additionally, based on the median and regression values, an attempt was made to fit a function describing the change in the tested values as a function of geometric parameters. This allowed for comparison of the impact of individual variables. The authors did not observe the research results in the available literature, they would discuss the influence of the channel shape of multi-channel systems on the value of the confining force. Therefore, according to the authors, the presented results constitute an important supplement to the available knowledge.

2

The Effect of Pressure on Compaction Process Parameters of Milk Thistle Straw With Binder

Kulig Ryszard

Journal of Research and Applications in Agricultural Engineering

|

2023

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Vol. 68, nr 1

33--39

EN

The results of research on determining the influence of pressure (from 45 to 113 MPa) on the compaction parameters of milk thistle straw (Sylibum marianum) are presented. Raw biomass and biomass containing the addition of a binder in the form of calcium lignosulfonate were investigated. Compaction was carried out using a Z020/TN2S Zwick universal testing machine and a pressing unit with a closed die. It was found that with increasing pressure, the density of material in the chamber and the density of the briquette rises (on average by 33.8%), and the mechanical strength of the finished product grows almost 3.5 times. Increasing the compaction pressure augments the compaction energy demand by an average of 84%. It was shown that the addition of binder increases the density of the briquette (by 22% on average) and raises the mechanical strength by 150% on average.

3

Evaluation of Density Fields of Numerical Analysis Output of Solid Carbon Dioxide Extrusion Process

Górecki Jan, Lindner Tymoteusz, Wałęsa Krzysztof

Advances in Science and Technology. Research Journal

|

2023

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Vol. 17, no 4

235--248

EN

Efforts to reduce energy consumption and explore alternative energy sources are paramount in production process research. However, a research gap exists regarding the evaluation of density fields in numerical analysis output of solid carbon dioxide (CO2) extrusion. This study aims to address this gap by examining the density fields in the numerical analysis output of the extrusion process for solid CO2, commonly known as dry ice. Dry ice, a by-product of ammonia compounds production, requires efficient management due to its high sublimation rate. Ram pressing is a commonly used method for compressing dry ice, but the resulting product often exhibits non-uniform density fields, presenting challenges for process optimization. To bridge this research gap, an algorithm is verified for determining the percentage share of density fields in the numerical simulation results. By comparing simulations using single- and multiple-cavity dies, the algorithm provides valuable insights into the distribution of density within the extruded solid CO2. In overcoming the limitations of subjective comparative evaluation, this study offers objective measures for assessing and comparing numerical analysis outputs. The findings contribute to a deeper understanding and optimization of the solid CO2 extrusion process, facilitating the production of high-density dry ice products with reduced energy consumption. In conclusion, this research not only bridges the research gap in evaluating density fields but also advances the field of solid CO2 extrusion and waste materials management.

4

A Novel Approach to Quantifying the Effect of the Density of Sand Cores on Their Gas Permeability

Sundaram Dinesh, Svidró József Tamás, Svidró Judit, Diószegi Attila

Journal of Casting & Materials Engineering

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2022

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Vol. 6, no. 2

33--38

EN

The density of moulding mixtures used in the foundry industry plays a significant role since it influences the strength, porosity, and permeability of moulds and cores. The latter is routinely tested in foundries using different solutions to control the properties of the moulding materials that are used to make moulds and cores. In this paper, the gas permeability of sand samples was measured using a custom-made setup to obtain the gas permeability in standard units instead of the usual permeability numbers (PN) with calibrated units. The aim of the work was to explore the effect of density variations in moulding materials on their gas permeabilities. Permeability in this work is quantified in SI units, square metres [m2]. The setup works based on Darcy’s law and the numbers obtained from the measurements can be used to deduce the gas permeability, k, of a sample. Two furan resin bonded mixtures with the same grain size distribution were hand-rammed with varying compaction forces to obtain a variation in density. Cylindrical samples (50 × 50 mm) were prepared using a silica sand aggregate sourced from a Swedish lake. The results of the measurement provided the difference in gas permeability between the samples that have varying densities. The results of permeability were then extrapolated by modifying the viscosity value of the air passed through the sample. In order to find the effect of apparent density variation on the pore characteristics of the samples, mercury intrusion porosimetry (MIP) was also performed. The results were in line with the gas permeability measurements.

5

The use of cohesive soils improved with lime as an example of circular economy in earthworks

Gosk Wojciech

Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

|

2022

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Nr 3

10--20

EN

A common practice in civil engineering during earthworks is the usual replacement of cohesive soils (fine soils), excavated during earthworks, with non-cohesive soils (coarse soils). Until recently, such a procedure was dictated primarily by economic and technical reasons. From an economic point of view, the ease of access and therefore low cost of using such soils instead of cohesive soils was crucial. The technical reason is, above all, the ease of compacting fine soils (as opposed to cohesive soils) and well-developed and well-known engineering methods for controlling their compaction. The situation changed radically when the new environmental regulations came into force and enforcement by the inspection authorities began. Currently, soil removed from a construction site according to regulations should be classified as waste. This fact has completely changed the approach of participants in the construction process to the use of local soils, especially cohesive soils (e.g. clays). Their use "on site" has stopped being an expensive option and has become a necessity. This paper presents aspects of the use of lime-improved cohesive soils that can be successfully used on site as excavation backfill. Problems related to the proper preparation of soil-lime composites are described, as well as the results of compaction tests. The paper presents the author's own methodology for selecting the content of quicklime in the soil-lime composite.

6

Sustainable deployment of crushed concrete aggregates strengthened with cement and sand

Sharma V., Kumar A., Kaur A.

Archives of Materials Science and Engineering

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2022

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Vol. 113, nr 1

19--34

EN

Purpose: Paper assessed the feasibility of crushed concrete aggregates (CCA), a subsidiary of construction and demolition (C&D) waste, blended with cement and sand to form a composite for civil engineering field applications. Design/methodology/approach: The compaction and strength characteristics of CCA were observed by conducting Proctor compaction and California Bearing Ratio (CBR) tests. Different proportions of CCA, sand and cement were used. Moreover, the effect of curing period (0, 4, 7, 14 and 28 days) was also studied. In addition, regression analyses were performed to develop empirical expressions to predict the compaction and strength characteristics of the CCA composite. Findings: Increasing the CCA content up to 50% increases the maximum dry unit weight (MDUW) and decreases the optimum moisture content (OMC). However, on further increasing its content the MDUW decreases and OMC increases. Percent increase in the CBR value can go up to 412% if the CCA content is increased up to 50%. However, the percent reduction in CBR of about 20% can take place if 100% CCA content is used. Moreover, multiple regression shows that the experimental results are in good agreement with the predicted values. Research limitations/implications: The results obtained are purely dependent on the type of material. However, they are in favour of the used material as a probable option for road sub-base layer, and also for reducing burden on available natural resources. Therefore, it is recommended to conduct some initial tests to confirm the feasibility of the material. Practical implications: The proposed study will guide the design Engineers to choose CCA as one of the potential materials for road construction. Originality/value: It was observed that there is a need to maximize the utilization of C&D waste without making any compromise with its mechanical properties. So keeping that in view, the present study was conducted.

7

Ruchy powierzchni terenu w rejonie pól geotermalnych obserwowane z zastosowaniem Satelitarnej Interferometrii Radarowej

Łukosz Magdalena A., Witkowski Wojciech, Lisowska Anna, Malinowska Agnieszka A.

Przegląd Górniczy

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2021

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T. 77, nr 4-6

36--45

EN

Land surface displacement in the area of geothermal fields observed by Satellite Radar Interferometry

8

Mechanizacja i technologia zagęszczania gruntów spoiwami hydraulicznymi

Stawowiak Michał

Magazyn Autostrady

|

2021

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Nr 6

40--45

PL

W niniejszym artykule przedstawiono problematykę związaną ze stabilizacją gruntów przy wykorzystaniu spoiw hydraulicznych na bazie cementu. Autor przedstawił również zagadnienia związane z podbudowami z nawierzchni betonowych. Ponadto w artykule omówiono podstawowe maszyny wykorzystywane do mieszania i zagęszczania gruntów podlegających stabilizacji spoiwami hydraulicznymi.

EN

This article presents issues related to soil stabilisation with the use of cement-based hydraulic binders. The author also presents issues related to the foundations of concrete pavements. Moreover, the article discusses basic machinery used to mix and compact soils stabilised with hydraulic binders.

9

A novel method and device for plastic mulch retriever

Khazimov Kanat M., Niyazbayev Adilkhan K., Shekerbekova Zhanbota S., Urymbayeva Aigul A., Mukanova Gulzhanat A., Bazarbayeva Tursunkul A., Nekrashevich Vladimir F., Khazimov Marat Zh.

Journal of Water and Land Development

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2021

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no. 49

85--94

EN

Plastic mulch provides a range of benefits including helping modulate soil temperature, reduce soil erosion, evaporation, fertilizer leaching and weed problems and increasing the quality and yields of the product. But when the crops are harvested, plastic mulch needs to be removed from the ground for disposal. Otherwise, these wastes are mixed with the soil and have a negative impact on yields by reducing the access of nutrients and moisture in the soil. The purpose of the current study is, therefore, to propose a roller for plastic mulch retriever which is applicable when the crops are harvested, and the plastic mulch needs to be removed from the ground for disposal. The winding mechanism of the plastic mulch retriever performs the main function and must have the high-quality performance of the winding operation in the removal technology. Research based on requirements of tensile strength test method and changes of strength characteristics of plastic mulch from various factors under natural conditions. The coefficient of compaction of the used plastic mulch (Krel), was the ratio of the diameter of the standard plastic mulch which was wound in the factory to the diameter of the used plastic mulch during the winding.

10

Development of a testing station for empirical verification of the algebraic model of dry ice piston extrusion

Górecki Jan

Acta Mechanica et Automatica

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2021

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Vol. 15, no. 3

107--112

EN

Efficient use of resources is a very important consideration for every production process, especially where waste materials are used as raw materials. One example of these kinds of processes is dry ice extrusion. Based on the subject literature, it can be observed that the machines available in the market that are used to compress dry ice are characterized by high working force value. This leads to low efficiency of resource consumption, in regards to both electrical energy and carbon dioxide. This paper presents a proposed design of a test stand used for measuring compression force as a function of piston displacement in the course of the dry ice extrusion. The first part of the article presents the testing methodology and test stand design. The second part presents the results of measurement of compression force as a function of piston displacement with three different die types. The results of the study allowed to establish the difference between the values of the measured limit force and the values calculated with an analytical model. The test stand design and the results presented in this paper are important for further research and development works in the area of efficient extrusion and compaction of dry ice.

11

GPR imaging of trafc compaction efects on soil structures

Akinsunmade Akinniyi

Acta Geophysica

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2021

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Vol. 69, no. 2

643--653

EN

Spatial and depth variability of soil characteristics greatly infuence its optimum utilization and management. Concealing nature of soil subsurface horizons has made the traditional soil investigations which rely on point information less reliable. In this study, an alternative use of ground penetrating radar (GPR)—a near-surface geophysical survey method—was tested to address the shortcomings. The focus of the study was on assessment of characteristics variability of soil layers at a test site and evaluation of efects of compaction caused by machinery trafcs on soil. GPR methods utilize electromagnetic energy in the frequency range of 10 MHz and 3.0 GHz. Fourteen profles GPR data were acquired at the test site-a farmland in Krakow, Poland. Compaction on parts of the soil was induced using tractor movements (simulating trafc efects) at difer ent passes. Data were processed using basic fltering algorithms and attributes computations executed in Refexw software. Attempt made in the study was on use of GPR geophysical technique for soil assessment. The method allows delineation of the soil horizons which depicts characteristic depth changes and spatial variability within the horizons. Moreover, trafc efects that caused compaction on parts of the soil horizons were discernable from the GPR profle sections. Thus, similar densifcation like hardpan that may develop in natural setting can be investigated using the method. The results have shown the suitability of the method for quick, noninvasive and continuous soil investigation that may also allow assessment of temporal soil changes via repeated measurement.

12

Study of compressibility in the raw materials recycling

Roman Kamil, Borek Kinga, Karwat Zbigniew

Inżynieria Materiałowa

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2020

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Vol. 41, nr 6

17--20

EN

The analysis of raw materials compression process assumes the modernization of testing machine. Testing machine will be equipped it additional prototype compacting tube. Added equipped allows to simulate the existing environment during the cyclic piston thickening process. The research set was supported by resistance sensors which helps to measure stress and displacement, recording values of stress and displacement. Characteristics of recorded values was registered according to resistance sensors using a specialized measuring bridge. The measured resistance value was equal to the value of stress and displacement, during the cyclic piston compaction. The measurements results allowed to transform the arithmetic function to into a formula, which determines the real values of stress and displacement. The maximum pressure of compaction in testing machine was 100 kN.

PL

Analiza przebiegu procesu zagęszczania surowców wtórnych zakładała modernizację maszyny wytrzymałościowej przez wyposażenie jej w dodatkową prototypową przystawkę zagęszczającą. Przystawka zagęszczająca pozwalała zasymulować środowisko występujące w trakcie procesu cyklicznego zagęszczania tłokowego. Zestaw badawczy wykorzystywał czujniki oporowe celem pomiaru naprężenia i przesunięcia, wykazując charakterystykę zależności pomiędzy wyżej wymienionymi wartościami. Charakterystyka występującego naprężenia i przesunięcia polegała na rejestracji rezystancji czujników za pomocą specjalistycznego mostka pomiarowego. Zmierzona wartość rezystancji odpowiadała przypisanym wartościom naprężenia i przesunięcia, które określono w trakcie cyklicznego zagęszczania tłokowego. Wyniki pomiarów pozwoliły na opracowanie funkcji arytmetycznej i przekształcenie jej do postaci wzoru, wyznaczając realne wartości naprężenia i przesunięcia. Maksymalny nacisk siły zagęszczającej wywołany przez maszynę wytrzymałościową wynosił 100 kN.

13

The Design of Ti-5Al-5Mo-5V-3Cr Elemental Powders Mixture Processing

Zyguła K., Wojtaszek M.

Archives of Metallurgy and Materials

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2020

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Vol. 65, iss. 1

283--289

EN

The aim of the study was to indicate the influence of consolidation processes on microstructure and selected mechanical properties of powder metallurgy Ti-5Al-5Mo-5V-3Cr alloy, which was produced by blending of elemental powders method. Morphology of the mixture and its ingredients were examined using scanning electron microscopy. The consolidation of powders mixture was conducted using two approaches. The first consisted of the uniaxial hot pressing process, the second included two steps – uniaxial cold pressing process and sintering under argon protective atmosphere. Microstructural analysis was performed for both as-pressed compacts using light microscopy. Additionally, computed tomography studies were carried out, in order to examine the internal structure of compacts. Chosen mechanical properties, such as Vickers hardness and compression strength was also determined and compared. The conducted research proves that the proposed production method leads to obtain materials with no structural defects and relatively low porosity. Moreover, due to the proper selection of manufacturing parameters, favorable microstructures can be received, as well as mechanical properties, which are comparable to conventionally produced material with the corresponding chemical composition.

14

Mechanism of biochar soil pore-gas-water interaction: gas properties of biochar-amended sandy soil at diferent degrees of compaction using KNN modeling

Garg Ankit, Huang He, Kushvaha Vinod, Madhushri Priyanka, Kamchoom Viroon, Wani Insha, Koshy Nevin, Zhu Hong-Hu

Acta Geophysica

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2020

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Vol. 68, no. 1

207--217

EN

Soil compaction has contrasting efect on soil strength (i.e., positive) and vegetation growth (i.e., negative), respectively. Biochar has been utilized mostly in combination with soils in both agricultural felds (i.e., loose soils) and geo-structures (i.e., dense soil slopes, landfll cover) for improving water retention due to its microporous structure. Biochar is also found to be useful to reduce gas permeability in compacted soil recently. However, the efciency of biochar in reducing gas permeability in loose and dense soils is rarely understood. The objective of this study is to analyze efects of compaction on gas permeability in soil at diferent degrees of compaction (i.e., 65%, 80% and 95%) and also diferent biochar amendment contents (0%, 5% and 10%). Another aim is to identify relative signifcance of parameters (soil suction, water content, biochar content and compaction) in afecting gas permeability. Experiments were conducted before applying k-nearest neighbor (KNN) modeling technique for identifying relative signifcance of parameters. Biochar was synthesized from a coastal invasive species (water hyacinth), which has relatively no infuence on food chain (as unlike in biochar produced from biomass such as rice husk, straw, peanut shell). Based on measurements and KNN modeling, it was found that gas permeability of biochar-amended soil is relatively lower than that of soil without amendment. It was found from KNN model that for denser soils, higher amount of soil suction is mobilized for a signifcant increase in gas permeability as compared to loose soils. Among all parameters, soil suction is found to be most infuential in afecting gas permeability followed by water content and compaction.

15

The characteristics of briquetting process with resistance sensors usage

Roman Kamil, Borek Kinga, Mazur Kamila

Przegląd Elektrotechniczny

|

2019

|

R. 95, nr 7

98--101

EN

The analysis of briquetting process assumes the simulation of biomass compaction process in specially prepared compacting tube. During the stress and displacement measures test set has been equipped with resistance sensors for the material compaction characterization. The measured resistance value responds to the assigned values of stress and displacement. Based on the results of the stress and displacement measurements the function of the compaction process was developed and transformed into the equation. The maximum compaction force pressure generated by the strength machine was equal 100 kN.

PL

Analiza przebiegu procesu brykietowania zakładała symulacje zagęszczanej biomasy w specjalnie przygotowanej głowicy zagęszczającej. Zestaw badawczy wyposażony został w czujniki oporowe do pomiaru naprężenia i przesunięcia charakteryzując zagęszczenie materiału badawczego. Zmierzona wartość rezystancji odpowiada przypisanym wartościom naprężenia i przesunięcia. Na podstawie wyników pomiaru wartości naprężenia i przesunięcia opracowano funkcję procesu zagęszczania przekształcając ją do postaci wzoru. Maksymalny nacisk siły zagęszczającej wywołany przez maszynę wytrzymałościową wynosił 100 kN.

16

Hot pressing of tungsten monocarbide nanopowder mixtures by electroconsolidation method

Gevorkyan Edwin, Rucki Mirosław, Chishkala Vladimir, Kislitsa Maksim, Siemiątkowski Zbigniew, Morozow Dmitrij

Journal of Machine Construction and Maintenance - Problemy Eksploatacji

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2019

|

no. 2

67--73

EN

The paper presents theoretical and experimental results in the field of the manufacturing of cemented tungsten carbide materials. The important issue of avoiding any additional substances like plasticizers was challenged in order to reach the maximal possible density of sintered material while keeping its purity. To solve the problem, the electroconsolidation method of hot pressing supported by direct current was applied. The respective apparatus was constructed that enabled WC nanopowders to be sintered under pressure and high temperature during a very short time of ca. 3 minutes. In the experiments, because of the short heating time, grain size of the sintered bulk WC increased insignificantly, in general, remaining smaller than 1 μm. Similarly, sintering under hot pressing with direct current, a mixture of 3% by weight Y2O3 stabilized ZrO2 and 50% by weight WC, produced a fine structure with a uniformly distributed WC grains. The applied electric field led to the formation of a temperature gradient around the pores, with a favourable impact on the compaction of large pores and an increase in the final density of the bulk material. The experimental research confirmed that the main mechanism of the densification of nanodispersed powders of tungsten monocarbide was a locally inhomogeneous diffusion-viscous flow with intergranular slipping.

PL

W artykule przedstawiono rozważania teoretyczne i wyniki badań eksperymentalnych dotyczących wyrobów z węglików wolframu uzyskiwanych metodą spiekania. Podjęto próbę rozwiązania jednego z problemów, jakim jest obecność substancji uplastyczniających, która wspomagając proces spiekania jednocześnie utrudnia uzyskanie maksymalnej gęstości gotowego materiału. W celu rozwiązania tego zagadnienia zastosowano metodę eloktrokonsolidacji, polegającą na spiekaniu wspomaganym przepływem prądu elektrycznego. Skonstruowana aparatura umożliwia spiekanie proszków węglika wolframu w bardzo krótkim czasie rzędu 3 minut. W badaniach eksperymentalnych wykazano, że krótki czas oddziaływania wysokiej temperatury na wzrost ziaren w strukturze spieku jest nieznaczny i rozmiary ziaren pozostają na poziomie 1 μm. Podobnie mieszanka 3% masy Y2O3 stabilizowanego ZrO2 z 50% masy WC umożliwiła uzyskanie spieku o strukturze zawierającej równomiernie rozłożone ziarna węglika wolframu. Zastosowanie prądu elektrycznego powoduje wytworzenie gradientu temperatury wokół porów, korzystnie wpływając na proces kompakcji i zwiększając wynikową gęstość spieku. Wyniki eksperymentów potwierdziły główne założenia stosowane w opisie teoretycznym kompakcji nanodyspersyjnych proszków węglika wolframu.

17

Complex analysis of GPR signals for the delineation of subsurface subtle features

Akinsunmade Akinniyi, Tomecka-Suchoń Sylwia, Pysz Paweł

Geology, Geophysics and Environment

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2019

|

Vol. 45, no. 4

257--267

EN

In this paper, complex signal analyses of ground penetrating radar (GPR) field data over an area of farmland in Krakow were interpreted alongside the basic filtered field data. The farmland was simulated with varying degrees of soil compaction induced by tractor movement. The focus of the study was the delineation of inherent characteristics of media through which the electromagnetic energy travelled. Fourteen GPR profiles were acquired from the area. The field data were subjected to pre- and post-processing prior to its the presentation and interpretation. Advance analysis operations on the field data which resorted in different attributes reveal more about the effects of the compaction on the soil than indicated by the basic filtered field data. Better resolution of subsurface layers boundary and lateral variation in the physical properties of the traversing media were well elucidated. The results have demonstrated that an advanced signal processing such as used in the study has ability to depict subtle characteristics of the propagating media.

18

A Method to Support Diagnostics of Dynamic Faults in Networks of Interconnections

Garbolino T.

International Journal of Electronics and Telecommunications

|

2018

|

Vol. 64, No. 3

407--420

EN

The article is devoted to the method facilitating the diagnostics of dynamic faults in networks of interconnection in systems-on-chips. It shows how to reconstruct the erroneous test response sequence coming from the faulty connection based on the set of signatures obtained as a result of multiple compaction of this sequence in the MISR register with programmable feedback. The Chinese reminder theorem is used for this purpose. The article analyzes in detail the various hardware realizations of the discussed method. The testing time associated with each proposed solution was also estimated. Presented method can be used with any type of test sequence and test pattern generator. It is also easily scalable to any number of nets in the network of interconnections. Moreover, it supports finding a trade-off between area overhead and testing time.

19

The use of computer image analysis in determining material flow in the roller press compacting unit during compacting of fine-grained material

Bembenek Michał

Computer Methods in Materials Science

|

2018

|

Vol. 18, No. 2

58--63

EN

Mechanisms of fine-grained material flow in a roller press are a constant subject of research. The proper transfer of feed in the feeder has a significant influence on the correct course of the compaction and consolidation process, product quality, and the intensity of wear of the forming components. A few mathematical models of compaction process have been put forth, but they are focused mainly on loads in the compacting unit and consolidated material properties. During compaction the loose material properties including the Young module, the external and internal friction coefficient, and the side pressure coefficient change continuously. Therefore visualisation tests were carried out to survey the flow of material in a compaction unit equipped with rollers with a flat working surface and gravity feeder. Using the NI Vision Builder program, the recorded video observations were analyzed and the medium speed distribution of the material in the feeder was determined. The results were presented in the form of graphs and compared with one another, specifying the relationship between the material speed distribution and the press operation parameters.

20

Predicting unit pressure indispendable for generation of specific compaction of a soil sample

Śnieg K., Błażejczak D., Słowik M.

Agricultural Engineering

|

2018

|

Vol. 22, No. 3

85--92

EN

The objective of the research was to construct an empirical model for prediction of a unit pressure indispensable for generation of a specific compaction of soil samples. Soil material in the form of loose mass was collected from the soil layer deposited in the depth from 35 to 40 cm and then its typical properties were determined (textural group, density of solid particles, humus content, reaction, plastic and liquid limits) and in order to compact it in Proctor apparatus and in the uniaxial compression test. Results of both tests were used for construction of regression models reflecting the course of the unit strength (Pρd) necessary to generate compaction (ρdj) equal to the dry bulk density obtained in Proctor apparatus (ρdp), in relation to the sample moisture (ρdm). Searching for relations was restricted to the scope of moisure between an optimal one acc. to Proctor and the soil plastic limit. It was stated that the pressure value Pρdp made on the soil sample in the uniaxial compression test depends significantly on ws and ρdm, and for description of this relation the use of multiple regression is sufficient. It was found out that for model samples with a textural group of silt loam and loam, differences in dry bulk density obtained in Proctor apparatus are approximately up to 0.15 g⋅cm-3.

PL

Celem badań było zbudowanie modelu empirycznego do prognozowania nacisku jednostkowego niezbędnego do wytworzenia określonego zagęszczenia próbki gleby. Z warstwy gleby leżącej na głębokości od 35 do 40 cm pobrano materiał glebowy w postaci luźnej masy, a następnie oznaczono jego typowe cechy własne (skład granulometryczny, gęstość fazy stałej, zawartość próchnicy, odczyn, granice plastyczności i płynności) i przeprowadzono testy zagęszczania w aparacie Proctora oraz jednoosiowego ściskania. Wyniki obu testów wykorzystano do budowy modeli regresji odwzorowujących przebieg nacisku jednostkowego (Pρdp), niezbędnego do wytworzenia w teście jednoosiowym zagęszczenia (ρdj) równoważnego gęstości objętościowej uzyskiwanej w aparacie Proctora (ρdp), w zależności od wilgotności (ws) i początkowej gęstości objętościowej szkieletu próbki modelowej (ρdm). Poszukiwanie zależności ograniczono do zakresu wilgotności pomiędzy optymalną wg Proctora a granicą plastyczności gleby. Stwierdzono, że wartość nacisku Pρdp wywieranego na próbkę gleby w teście jednoosiowego ściskania zależy istotnie od ws i ρdm, a do opisu tej zależności wystarczające jest zastosowanie regresji wielorakiej. Uzyskano, że dla próbek modelowych o składach granulometrycznych pył gliniasty i glina zwykła, różnice gęstości objętościowych szkieletu uzyskiwanych w aparacie Proctora wynoszą do około 0,15 g⋅cm-3.