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Number of results: 22
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Abstract

The problem of consolidation of soil has been widely investigated. The basic approach was given by Terzaghi who assumed soil of constant physical and mechanical parameters. In the case of peat consolidation, the permeability coefficient of soil and the elasticity modulus are functions of the settlement which is an important additional factor. The model proposed here assumes varying the elasticity and permeability coefficients. Moreover, the settlement is described by the so-called elementary curve which was approximated empirically based upon laboratory tests. The model allows to consider the case when the filtration in the peat body goes in horizontal direction. It happens so when the charging layer does not receive outgoing water from the pores. The model includes also the case when the load involving consolidation varies in time i.e. the charging layer grows up gradually. The model has been applied practically in several cases and it comes that there is a good agreement between calculated and measured settlement of the consolidated peat layer.

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Authors and Affiliations

Z. Meyer
R. Coufal
M. Kowalów
T. Szczygielski
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Abstract

Land consolidation procedures are an attempt to comprehensively change the existing spatial structure of land in rural areas. This treatment also brings many other social and economic benefits, contributing to the development of consolidated areas. Land consolidation in mountain areas differs in many respects from those implemented in areas with more favorable conditions for the functioning of agriculture. The unfavorable values of land fragmentation indices, terrain conditions and lower than the average soil quality affect both the dominant forms of agricultural activity and the limited opportunities to improve the distribution of plots in space, parameters of shape, and the area as a result of land consolidation. For this reason, the effectiveness of land consolidation in mountain areas can be achieved by improving the quality of transportation network and the accessibility of the plots, arranging ownership issues and improving the quality of cadastral documentation. This article presents the evaluation of the measures of effectiveness of land consolidation realized in mountain areas on the example of Łetownia Village in the Małopolska Province, located in the southern part of Poland. Selected village is an area with unfavorable conditions for the functioning of agriculture and high values of land fragmentation indices.
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Authors and Affiliations

Jarosław Janus
Magdalena Łopacka
Ewa John
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Abstract

The paper presents a new method of determination of economic benefits of land consolidation of farms, which result from reduction of land parcels' number. A model method and a logical method have been applied. The discussed economic benefits have been determined by means of comparing economic evaluation of a model farm's land configuration before and after land consolidation. As a result of analysis, a mathematical formula that describes an economic benefit of land consolidation, resulting from the reduction of land parcels number, has been derived. The economic benefit is a function of the differences between the numbers of arable fields and the differences between the area of an arable lands and green lands of a farm, before and after land consolidation, as well as constant parameters and slope of linear regression equations for the models of such fields. The benefit does not depend on the area of farms.
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Authors and Affiliations

Stefan Mielewczyk
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Abstract

The drainage consolidation method has been efficiently used to deal with soft ground improvement. Nowadays, it has been suggested to use a new sand soil which is a composite of sand and recycled glass waste. The permeability performance of glass-sand soil was explored to judge the feasibility of glass-sand soil backfilled in the drainage consolidation of sand-drained ground. For comparison purposes, different mix proportions of recycled glass waste, fineness modulus, and glass particle size were analyzed to certify the impact on the permeability coefficient and the degree of consolidation. The numerical results show that adding a proper amount of recycled glass waste could promote the permeability performance of glass-sand soil, and the glasssand soil drain could be consolidated more quickly than a sand drain. Experiments showed that glass-sand soil with the a 20% mix of recycled glass waste reveals the optimum performance of permeability.

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Authors and Affiliations

F.C. Wang
X.N. Feng
H. Gong
H.Y. Zhao
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Abstract

Unfavorable spatial structure of arable land located in Małopolska is a major obstacle in conducting agricultural activity. Arable lands located in the southern part of Małopolska are fragmented, have small area, and irregular shapes. Agricultural activity on land with an unfavorable spatial structure is associated with an increase in production costs, which directly results in lower income of farms. One of the methods of improving spatial conditions is to implement land consolidation works. They allow to organize the spatial structure, increase the area of agriculturally used parcels, while reducing their number. The article presents a new approach in determining the parameters of land fragmentation. GIS tools were used to identify areas with unfavorable spatial parameters. The methodology which allows for the processing, filtration of source data, determination and visualization of land fragmentation parameters is discussed. As part of the research, the Binning method was used, which allows to visualize the phenomenon and simultaneously reduce the data used. In the work, a detailed assessment of land fragmentation parameters was made, which can be used in agricultural land management works. Analyzes have shown that the southern areas of the Nowy Targ County are characterized by intensive fragmentation of arable land. There are also unfavorable parameters related to the elongation and shape of parcels in the discussed areas.

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Authors and Affiliations

Piotr Bożek
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Abstract

The rapid surge of global oil prices, on account of the pent-up demand after COVID-19 and the Russian-Ukraine war, has significantly contributed to the cost-push inflation as well as twin deficits, predominantly in developing economies. Motivated by the intention to curb the inflation, governments of several oil-dependent economies have rolled out fiscal measures to provide immediate relief to households through subsidizing the fuel component of the consumption basket. This paper provides a case study of Pakistan, wherein the effectiveness of untargeted gasoline and diesel subsidies has been gauged against alternative direct disbursement mechanisms. The analysis reveals that under the price-control based indirect subsidy disbursement mechanism, only 11% of the total domestic subsidies were directed to the poorest 40% of the households, whereas approximately 55% of the total subsidies were allocated to the 20% of the most liquid household segment. The case study analyzes the performance of alternative direct subsidy disbursement mechanisms which transpires into the potential fiscal savings of PKR 74.63 billion, while providing coverage to 40% of the lowest household segment. The study also evaluates the implication of the pass-through of the true prices on the national consumption of gasoline and diesel in the short-term, which reveals the sharp reduction of petroleum consumption in the total bill from 37% to 23%, thereby providing substantial relief to the current account balance. The finding provides key insights for economies to institutionalize the necessary social protection system and progressively transit to the direct subsidy disbursement mechanism while striving to contain the cost-push-based inflation triggered through the rapid movement of global oil prices.
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Authors and Affiliations

Talha Khalid
1
ORCID: ORCID

  1. Policy and Planning, Central Power Purchasing Agency, Pakistan
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Abstract

All local government units in Poland have been analysed regarding their consolidated debt. The consolidated debt was compared with the budget debt which is subject to monitoring and statutory restrictions. The scale of extra-budgetary debt has been revealed as recorded in the balance sheet of a local government unit, a parent entity. In practice, the consolidated balance sheet and debt presented in it are not subject to debates and analyses. Local governments refrain from auditing and publicising of the consolidated balance sheet. The article describes the risks related to unlimited local government debt.

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Authors and Affiliations

Mieczysław Czekaj
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Abstract

The paper presents a global perspective of the current technologies used for steel production and the steel markets. The iron and steel industry is a very complex sector that is strongly related with the rest of the economy due to the importance of steel products for industries such as construction, automotive, and other manufacturing sectors. Moreover, the iron and steel industry demands significant amounts of raw materials and energy, and most companies producing raw materials are located remote from the areas of highest steel demand. In consequence, both steel products and inputs are traded internationally (mostly by sea) and in large quantities, what additionally complicates analyses of the iron and steel industry. Steel prices depend on several variables, and there is not a single price for steel since there is a great variety of steel products traded. Those prices depend on supply and demand interaction (between steel producers and consumers, but also on interaction with other industries competing for the same inputs), and on transport conditions. As concerns the ownership structure, the steel industry consists of some large firms that operate globally and produce significant output, and many small firms that operate at a lesser scale. Recently, some of those firms have consolidated into large multinationals (such as ArcelorMittal, formed in 2006 by the merger of Arcelor and Mittal Steel, Arcelor being the result of the previous merger of Aceralia (ES), Usinor (FR), and Arbed (LX) in 2002). The results of this article form the basis for further long- and mid-term analyses of the development of the global steel industry. The main conclusion of the paper is that any future analysis of the iron and steel industry should be based on quantitative modelling tools that: (i) properly capture the technological diversity of the industry and the key features of the supply chain, (ii) are able to consider the strategic behaviour of all the key players of the industry, and (iii) consider all those factors at the global scale.

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Authors and Affiliations

Ignacio Hidalgo González
Jacek Kamiński
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Abstract

Each year, mine and mill operations generate enormousamounts of two waste types – fine-grained tailings andcoarse-grained waste rocks. Fine-grained tailings are either discharged in slurry form to surface tailings dams ordelivered in cementitious form to underground mine stopes as backfilling, while coarse-grained rocks are typicallystored by depositing as a dry material in large dumps. The engineering design of surface tailings dams orunderground mine stopes is often controlled by the high compressibility and low shear strength characteristics offine-grained tailings. Cemented paste backfill CPB indicating saturated, fine-grained backfills can undergo majorconsolidation settlement during early curing stages. Thus, a better understanding of the rate and magnitude of bothdifferential and total settlement of CPB cured under stressis essential for a proper backfill geotechnical design. Theconsolidation parameters of CPB can be determined from an improved lab setup called CUAPS (curing underapplied pressure system). This setup is capable of simulating the CPB placement and curing conditions, andmeasuring the consolidation parameters of CPB cured under effective stresses ranging between 0.5 and 400 kPa.In this study, a series of one-dimensional consolidation tests were conducted on CPB samples allowing forexamination of the effects of binder type and rate as well as curing time on the compression properties (e.g.,coefficient of consolidationcv, compression indexCc, and recompression indexCr) and the final geotechnicalindex properties (e.g., void ratioef, water contentwf, and degree of saturationSf). Results showed that as the bindercontent increases, the initial resistance to consolidation increases. Thecvvalue decreases over the course of timedue to evolution of the CPB microstructure generated by the hydration process.

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Authors and Affiliations

Erol Yilmaz
Tikou Belem
Mostafa Benzaazoua
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Abstract

This work investigates the compaction behaviour of commercial pure aluminium chips (CP Al) produced during a machining operation and subsequently consolidated by Equal Channel Angular Pressing (ECAP). Empirical models were developed to describe the relative density and hardness of the compacted product of ECAP as functions of the initial machining input parameters including cutting edge angle (CA), depth of cut (DOC) and then the number of consolidation pass during ECAP. The models were developed utilizing response surface methodology (RSM) based on data from a central composite face centred factorial design of experiments approach. The models were then validated by using Analysis of Variance (ANOVA). The effect of input parameters on the relative density and hardness of the ECAP consolidated samples are presented and discussed including details as regards to the mechanical and microstructural properties. An optimum set of input parameters are identified and presented where the best relative density and hardness are demonstrated.
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Authors and Affiliations

R. Palanivel
1
ORCID: ORCID
S. Vigneshwaran
2
ORCID: ORCID
A. Alshqirate
3
ORCID: ORCID
R. Madhavan
2
ORCID: ORCID
P. Venkatachalam
4
R.F. Laubscher
5
ORCID: ORCID

  1. Shaqra University, Department of Mechanical Engineering, Saudi Arabia, 11911
  2. National Institute of Technology, Department of Mechanical Engineering, Puducherry, Karaikal – 609 609, India
  3. Department of Mechanical Engineering, Faculty of Engineering Technology, Al-Balqa Applied University, Jordan 19117
  4. Department of Mechanical Engineering, MVJ College of Engineering, Bengaluru – 560 067, Karnataka, India
  5. Department of Mechanical Science & Engineering, University of Johannesburg, South Africa
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Abstract

Theoretical analysis of the dewatering and consolidation process of the wet paper web with the air through- blowing technique is presented in this study. This kind of process takes place in a new (patented) device called the air press. The results of theoretical considerations are experimentally verified. The experimental research was conducted on a specially designed experimental stand with the use of three kinds of paper used for oil and air filtration. It was proven that the air through-blowing process of the fibrous web dewatering can be considered as unidirectional consolidation with the linear relationship of dehydration and deformation. A new system of devices was suggested for the continuous production of high quality filter papers, with the air press as its basic element.
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Authors and Affiliations

Włodzimierz Kawka
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Abstract

The influence of rebar, protruding from concrete element during casting, on temperature and strength development was analyzed. Test models of size 50 cm x 50 cm x 50 cm were made with and without protruding rebar. The rebar protruding from the sample simulated the conditions of the hardening of elements such as bridge abutments or pylons, which require technological break. Samples were cast in insulated formworks, to create semi-adiabatic conditions for concrete curing, simulating real conditions of curing of mass structures. The research utilized selfconsolidating concrete with two different rapid hardening cements: CEM I 42.5R and CEM I 52.5R, and blastfurnace cement CEM III/A 42.5N. Continuous registration of temperatures in the samples was performed for the first 7 days. Based on the results acquired and compressive strength, the amount and kinetics of the heat given off in the concrete was determined and an evaluation of its strength in conditions simulating actual conditions was performed. The research showed that the difference in temperature between the reinforced and non-reinforced sample was approximately 14.0° C.

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Authors and Affiliations

Maria Kaszyńska
ORCID: ORCID
S. Skibicki
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Abstract

The pattern of pore water pressure dissipation from the one-dimensional consolidation test significantly affects the calculated value of the coefficient of consolidation. This paper discusses the interpretation methodology for laboratory dissipation data from the oedometer test with the pore water pressure measurements or Rowe cell test. In the analysis, the gradient-based algorithm for finding the optimal value of the coefficient of consolidation is used against experimental results, obtained for various fine-grained soils. The appropriate value of coefficient of consolidation is considered as one with the lowest associated error function, which evaluates fitness between the experimental and theoretical dissipation curves. Based on the experimental results, two different patterns of the pore water pressure dissipation are identified, and the saturation of the specimen was found to be the key factor in describing the change in the patterns. For the monotonically decreasing dissipation curve, an inflection point is identified. The values of degree of dissipation at the inflection point are close to the theoretical value of 53.4%.
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Authors and Affiliations

Bartłomiej Szczepan Olek
1
ORCID: ORCID

  1. Krakow University of Technology, Faculty of Civil Engineering, Warszawska 24, 31-155 Kraków, Poland
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Abstract

Memory trace is an effect of temporary arousal (perception, experience, action) that causes a specific change in the nervous system. Memory allows to record and recall various information, thus enabling to learn new things. It is an extremely active and dynamic process. The influence of emotions on memory is obvious, largely determined by the close cooperation of the amygdala (responsible for emo-tions) and the hippocampus (memory processes).
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Authors and Affiliations

Paulina Fałek
1
Artur Fałek
1
Monika Kager
2
Richard Kager
3
Piotr Walkowicz
2
Marcin Kubiak
2
Elżbieta Starosławska
2
Franciszek Burdan
2 4

  1. Independent Public Healthcare, Puławy, Poland
  2. St. John’s Cancer Center, Lublin, Poland
  3. Public Independent Clinical Hospital Number 4, Lublin, Poland
  4. Human Anatomy Department, Medical University of Lublin, Lublin, Poland
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Abstract

Poland is characterized by a number of factors which adversely affect the agricultural economy, so this paper will aim to present the possibilities of using multi-criteria decision-making methods of Analytical Hierarchy Process (AHP) in the analysis of the spatial structure of rural areas. AHP is a widely used tool for making complex decisions based on a large number of criteria, such as, for example, land consolidation works on fragmented agricultural land. The first step is to formulate the decision-making process, then the assessment criteria and the solution variants guided by expert knowledge are determined.

A ranking, according to which the order of land consolidation and land exchange works in the studied area should be determined, will be defined by using decision-making models of the AHP method. The basis for calculations will be the weights received for the factors/parameters defined for the five thematic groups. Calculations for individual villages will bemade, and then the obtained results will allow creating a ranking for the studied commune, allowing for the effective (in terms of economic and socio-economic) spending of funds for this purpose. The presented method can be successfully used to conduct analogous analyses for any area.

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Authors and Affiliations

Grzegorz Oleniacz
Izabela Skrzypczak
Przemysław Leń
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Abstract

Basing on experimental data, the possibility of consolidating side products of turning, milling and drilling of aluminum alloys into the form and properties of solids metals using low-temperature KoBo extrusion method has been assessed. Research regarding mechanical and structural properties of the final products revealed their total consolidation and proved their compatibility with requirements for products made of bulk billets. Importantly, the chips consolidation process does not require high or even raised temperature, which significantly reduces the unfavorable phenomenon of chips oxidation and its negative influence on the structure and mechanical properties of products. A very good effect of chips compaction has been proved by KoBo method, which has been confirmed by relatively slightly different mechanical properties of the material after recycling compared with the bulk one. Among currently applied techniques of consolidation of dispersed fractions in a solid state (leaving the melting stage out), the KoBo method seems an innovative way of utilizing metallic chips, as it enables a cold deformation process.

The paper presents investigations using 2024 and 7075 aluminum alloys chips from manufacturing process, formed into briquettes and deformed under conditions of KoBo extrusion process, which enables to obtain long product by cold forming. The final product characterized by good microstructures, mechanical features and low cost of production.

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Authors and Affiliations

B. Pawłowska
R.E. Śliwa
ORCID: ORCID
M. Zwolak
ORCID: ORCID
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Abstract

The presence of soft soil of river and organic genesis in the basement of road embankments creates problems related to their high deformability. Difficult to assess water permeability, affecting the course of the consolidation and settlement process, requires field studies, such as dilatometer tests. In engineering practice, there are many factors that can affect the basement consolidation process, but they are not simply applied to theoretical models. In many cases, only the observational method allows the selected computational approach to be applied to a specific engineering problem. For this reason, it is one of the approaches strongly emphasized by Eurocode 7. The article presents an example of the application of a temporary load from heavy construction traffic to the consolidation of soft soil under service roads with verification of the subsoil parameters using the dilatometer tests. A horizontal layer of weak soil, loaded with a vertical external load caused by temporary traffic, was assumed for the calculations. For such an arrangement, the classical solution of uniaxial Terzaghi’s consolidation with the water flow in the vertical direction was applied. A computational analysis of the consolidation time and maximum settlement values was performed.
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Authors and Affiliations

Grzegorz Bartnik
1
ORCID: ORCID
Rafał Kuszyk
1
ORCID: ORCID
Małgorzata Superczyńska
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland
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Abstract

This paper presents simulation results of the consolidation process of the flotation waste landfill “Żelazny Most”. The mathematical model used in presented research is based on Biot’s model of consolidation and is extended with rheological skeleton. The load is the mass pressure of the landfill itself. The initial point selected for calculations was based on the ground water level calculated in a landfill. The creeping process in this waste landfill was analyzed along the north – south section. The solution is therefore 2D with the assumption of a plane strain state. Effective model parameters data were obtained in laboratory tests on the material from the waste landfill. Results obtained for a stress state in a storage state can help to determine whether the adopted linear model of visco-elastic medium does not lead to changes in the Coulomb – Mohr potential yield, showing the emergence of plasticity of material storage areas.

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Authors and Affiliations

T. Strzelecki
M. Bartlewska-Urban
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Abstract

Social and Economic Costs of Spatial Disorder in Agriculture. The main objective of the study was the identification of the phenomena of chaos in the structure and spatial organization of agriculture, that is the agrarian fragmentation of farms, exclusion of land from agricultural production in suburban zones and the fragmentation of the agricultural landscape. These processes cause a major increase in economic and social costs, which results in the loss of resources and spatial disorder in agriculture. An attempt was made to estimate the costs of these processes in economic, social and environmental terms. The economic dimension of spatial disorder in agriculture is manifested by negative results in the production and consumption sphere related most often to high labour costs, and consequently to low incomes. The social dimension of spatial disorder in agriculture is demonstrated by the effects of de-agrarization processes and deformation of social structures. De-agrarization means the processes of agricultural area reduction, extensification and fallowing as well as an increasingly limited significance of agriculture as a workplace and a reduction in the source of income by rural residents. A conducted analysis of spatial disorder in agriculture resulting from the lack of appropriate regulation and taxation systems as well as historical factors allowed determining direct and indirect results influencing the structure and spatial organization of agriculture. Direct results include: a chessboard pattern of agricultural land, marginalization of the agricultural function in rural areas which mostly applies to suburban zones, unregulated ownership of farmland, its unjustified designation for other purposes, a decrease in biodiversity in agriculture and fragmentation of the agricultural landscape. Indirect results include: an increase in the costs of agricultural production, expensive agricultural-installation plans, loss of direct payments, easement appurtenant, the emergence of human-environment conflicts and major transformations of the agricultural landscape in a suburban zone.
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Authors and Affiliations

Barbara Maćkiewicz
Anna Kołodziejczak
Magdalena Szczepańska
Benicjusz Głębocki
Ewa Kacprzak

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