The paper presents the investigations of influence of sweet corn cobs storage conditions on mechanical properties of kernel. The main research was preceded by the determination of the plant materials characteristics. The tests of kernel separation, penetration and pressing were made on the universal machine Instron 6022. It made it possible to determine the values of the separation, penetration and pressing forces and energy. The measurements were taken for the cutting heads movement speed 50 mm^.min^-1 and its loading 100 N. The tested cobs were stored for 48 hours in a coolhouse (0–3ºC), in a closed room (18–22ºC) and in water environment. The obtained tests results were compared with the control group, i.e. for the cobs tested immediately after harvesting. The analysis of the results showed that storage conditions had a significant influence on value loss in the kernel’s mechanical properties and on the energy consumption in the case of separation and penetration and on their rise in the case of pressing. This is especially important in the process of kernel separation from a cob core and in its further processing.

The quality of prediction of annual electricity sales to rural customers made on the basis of non-structural models: classical and coming from the theory of deterministic chaos were analysed in the study. The analysis has shown that in conditions of large changes of annual electricity sales, forecasting made on the basis of Prigogine’s and Schuster’s models are characterised by higher quality than forecasting made on the basis of classical non-structural models.

The influence of methods of parsley root pretreatment (different slices dimensions and blanching) before convection drying on the kinetics of dried product rehydration were examined. Kinetics of the process was tested within the range of 0–6 hours. Relative increase in mass of dried parsley root was determined. The approximation of experimental data with assumed kinetic equation gave good results. Analysis of the rehydration course showed that slices dimensions and blanching influence the kinetics of dried parsley root rehydration.

This paper presents the result of experimental study on traction forces, traction efficiency generated by the different tyres in different soil conditions. The field experiment was carried out in forest conditions. The relationship between type of tyre (there was used four type), values of vertical load (there were used five level of loading), traction forces and the level of traction efficiency are studied. In experiments double tyre and with tyre chain was also carried out with. Experiments showed that using double tyre and tyre chain are good way to improve traction properties, and that each tyre has optimal vertical loading for the best traction properties.

An algorithm, based on Prony approach, for identification of the relaxation modulus of linear viscoelastic materials described by Maxwell model is presented. It is proved, that if the real relaxation modulus is four-element Maxwell and the measurements are not corrupted by noise, then the identifiability of the real parameters of the relaxation modulus is guaranteed. It is also proved that all the computational tasks solved in the identification scheme are well-posed in the Hadamard sense. Next the necessary and sufficient conditions for the applicability of the algorithm to identifying the four-parameter Maxwell models are derived. The effectiveness of the method is demonstrated through the computation of the relaxation function of the beet sugar root samples in the state of the uniaxial strain. The second example using Lanczos data is also enclosed.

The paper presents results of stress relaxation tests under uniaxial stress and strain conditions. Tests were carried out on cylindrical samples of Rubin apple flesh. On that basis changeable in time bulk modulus and shear modulus were determined. Application of quasi-static and impact loading enabled to compare apple flesh behaviour at different initial deformation rates.

The article presents trends in development of modern structures for control of packaging machines. A system for automation of the product packaging system has been worked out, consisting of the automation scheme and the control algorithm. An application has been designed that realizes the described process for a logical controller. The facility studied was a packaging line for small collective packs of agricultural products. The modification consisted in introduction of optical sensors sending input signals to a PLC controller designed according to ladder diagram (LD). On the basis of the data from ISHIDA scales, the system selects the relevant control algorithm. The solution presented meets the requirements for packaging lines consisting in the possibility of internal integration and later modification.

A concept for an automatic system controlling the milk pasteurization process was designed, together with the process visualization. The article presents short characteristics of the facility studied and the construction of the milk pasteurization line. An opportunity has been presented to modernize the control of the milk pasteurization line using a PLC controller. An application was prepared for computer visualization in the InTouch software by Wonderware^®, which – together with the relevant software – will serve for supervision of the milk pasteurization process. In the event of breaching the critical values, it will launch an alarm and appropriate procedures preventing production of faulty goods. The automatic control system for the milk pasteurization line will allow for control of technological processes and maintenance. Furthermore, it will facilitate archiving of the process data and their analysis, at the same time facilitating use of the installation.