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Fuel Consumption and Effectiveness of Elimination of Energy-crop Willow Plantation

Abstract

The objective of the paper was to determine fuel consumption on elimination of the energy willow plantation with current mechanical methods with the use of the machine research model. The paper covers investigations of four machine units. The lowest fuel consumption (142.6 l∙ha−1) with the use of Meri Crusher MJS-2.0) did not ensure effectiveness of operation of this unit. Efficiency of elimination of the plantation in this case is only 36.4%. On the other hand, the highest consumption of diesel oil (776.4 l∙ha−1) was reported for FAO FAR model FV 4088, and the effectiveness of elimination was not satisfactory and it was 57.0%. The highest effectiveness of elimination of the plantation was reported for the model of a new machine. Fuel consumption in this case was 535.7 l∙ha−1 and the willow plantation elimination effectiveness was the highest and it amounted to 94.8%.

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Granulated Coffe Grounds Effect on Selected Physico-chemical and Functional Properties of Soil

Abstract

The study evaluates granulated coffee grounds use as an additive to soil. Specific physico-chemical and functional properties of soil that enable assessment of its fertility and that have a possible impact on plants growth and development were analysed. The research proved that granulated coffee grounds added to soil increase sorption properties and decrease pH of the soil solution. Moreover, the increase of the phenol compounds that decreased the germination ability and reduced the length of roots of a test plant, namely winter wheat, was reported.

Open access
Influence of high temperatures on technical state of streets and roads structures with asphalt surfacing

Abstract

In this paper will be presented the influence of high temperatures on asphalt street pavement in terms of the influence of temperature on permanent deformations and thus the technical condition of the streets, comparable to the effects induced on extra-urban roads.

Environmental factors are one of the mayn factors being assaulted in operation and road structures are very important in terms of the influence they can have on the state road transport technical infrastructure.

Will be presented differences between urban road structures (streets) and extra-urban (road) both in terms of construction, the demands of traffic and environmental conditions to which they are subject.

Road structures extra-urban and urban areas are required differently in terms of the environmental conditions of the location ambient different thereof, that is, when the streets they are inside localities and the built environment significantly affect road infrastructure, unlike in the case of roads where they are located just outside the settlements, reducing the effect of air currents accumulation pavement surface temperature.

To demonstrate the influence of high temperatures on the pavement were conducted laboratory tests on asphalt mixtures in order to demonstrate the occurrence of reduction of physical characteristics, with adverse implications on the performance of applications similar to traffic.

Open access
Mathematical Modeling of Actinidia arguta (Kiwiberry) Drying Kinetics

Abstract

Consumers and scientists exhibit a growing interest in bioactive ingredients of natural origin with strong pro-health effects. Such properties have been found in fruits of of Actinidia argute, commonly known as kiwiberry (mini kiwi or hardy kiwi). Appropriate methods and parameters of the drying process enable obtaining a product with preserved high pro-health properties. The obejctive of this paper was to study the influence of the selected drying methods on the drying kinetics of actinidia. Commonly known mathematical models were used to describe the process. The kinetics of convective, microwave-convective, infrared and vacuum drying was investigated. The process was performed until samples reached dimensionless moisture ratio (MR) of 0.02. The quickest method was vacuum drying reaching moisture ratio target after 286 min, and the slowest was convective drying characterized by 1352 min of drying. In general, Midilli et al.’s model was evaluated as the most adequate for description of the moisture transfer in the fruit samples.

Open access
Mathematical Models for Nonlinear Soil Behavior

Abstract

Actually, the seismic movement has an irregular cyclic character.This can be equivalent to a determined number of uniform cyclical stresses equivalent in terms of effect.

Modeling the behavior of the soil to cyclical stress, is usually done, by establishing a relationship for primary loading like τ = f (γ) and after drawing the diagram “effortless strain curve”, in which τ is the stress, and γ is shear deformation. For modeling nonlinear behavior of the soil, we used like nonlinear models. The best known are the hyperbolic model and the Ramberg-Osgood model.

Open access
Modelling of the Separation Process of the Potato Stack

Abstract

The most time consuming and the least mechanized process of potato cultivation is its harvesting. Therefore, now, as never before, we have faced a problem concerning the improvement of the existing and construction of new devices for potato harvesting and their provision to the cultivation industry. It requires further development of theoretical, complex and extensive research on the phenomenon of separation of the potato stack, which will enable justification of optimal work modes of the existing separating devices and will be used for the synthesis of basically new, more advanced separators

Open access
Parametric Study on How the Lateral Forces Acting on a Deep Foundation Influences the Axial Forces Developing in the Piles

Abstract

A missing piece in the design of bridge substructure is that the equation given in structural mechanics that assesses the axial forces in the piles of a deep foundation does not take into account the effect of lateral forces acting on the pile cap. In practice, pile forces are determined using a FEA software. This method, however, can not be easily incorporated into an automated program that performs local and global optimizations of a structure. One of the reasons is that this method is particularly demanding on the computational resources. Since a bridge can have a number of deep foundations, which must be verified for various combinations of actions, which need to be optimized, recalculated in various scenarios and then the entire process reiterated for all structural solutions, computational cost can become prohibitive. Another reason is that due to the lack of a relation between all the parameters and dimensions that influence the behaviour of a deep foundation, their optimization is difficult.

For this purpose, a parametric study has been carried out to investigate what parameters influence the relation between the lateral forces applied to the foundation and the axial forces that develop in the piles, and ultimately propose an equation that takes into account the lateral forces. The study is carried out using experimental data obtained on models using the finite element analysis method using SAP 2000 (v.15) software.

Open access
The Sunet System for Monitoring Noise Pollution in Cluj-Napoca

Abstract

In Europe the need for local authorities to provide a high standard of living for their communities led to the establishment of the European noise mapping directive 2002/49/EC. Whilst Noise mapping itself doesn’t need continuous noise monitoring, states must produce a noise action plan which highlights actions they intend to take to reduce the number of people affected.

SUNET platform (System for Urban Noise and Eco-Traffic) was designed for improved management of the noise pollution in Cluj-Napoca and to provide up-to-date public data on a user-friendly interface. The implementation of the application over the entire municipality is highly advantageous for it creates a link between the town’s administration (the local authorities, the City Hall of Cluj-Napoca) and the user (the citizens) through this system which is dynamic, modern and compliant with the European regulations.

Open access
Analysis of Power Equipment Level on the Example of Farm Tractors in Selected Farms of Przeworsk Province

Abstract

Decisions concerning investments in farm tractors is a significant problem of modern agricultural production. Ensuring efficient performance of agrotechnical treatments and a rational level of use of tractors in the aspect of exploitation costs are a derivative of the power equipment level in a farm. The paper presents studies carried out in 31 selected farms, which run production on the total acreage of 937 ha of agricultural land (AL) and exploit 70 tractors. Analysis covered information on: area of farms, number and power of used tractors, investments in technical equipment concerning purchase of farm tractors and a production profile. In the investigated farms at the average per 100 ha of the agricultural land area there was 7.47 tractors, 90% of respondents actively used subsidies available from the EU structural funds. A high energy equipment level was determined in particular in farm with a smaller acreage. Over 87% of farm used more than one tractor and the age of the third each did not exceed six years.

Open access
Assessment of Changes in Sod Under Intensive Use

Abstract

The paper presents research results which aimed at evaluation of the change in the sodding degree and selected strength parameters of sod used with varied intensity; additionally sod was modified through administration of biopreparation. Measurements were taken on two types of sod. The first one was formed from perennial rye grass, the second one from orchard grass. It was proved that the use of the investigated facilities resulted in reduction of sodding, which was related to the sod forming species. No impact of biopreparation use on the sodding degree was proved. Intensive use affected the increase of the value of the analysed strength parameters; at low soil moisture (5.0-5.5%) considerable compaction in the surface layer of soil was reported.

Open access