Drying kinetics on mass reduction with natural operation of potatoes as simulation model

The increase in cases of coronavirus infection causes research to be carried out at home. This is due to the rapid mutation of the coronavirus. So far, WHO has confirmed 4 variants of the coronavirus. The research carried out this time is to make a kinetic model and the percent reduction in mass in potato samples by drying using sunlight as a form of research effort carried out at home. This drying has been done before and this time it is compared with previous research data. The results obtained are that there is a difference, namely the percent reduction in sample mass before and after drying. In the sample carried out this time, the percent mass reduction on the first day was very large, but when tested on the last day it was superior to the previous research, which means that the surface area of the sample accelerates the drying process.

Diagnostics of Bridge Bed Sections and Approaches in Zones of Expansion Joints on Road Bridges

The object of the study is durability of expansion joints in bridge structures; the subject of the research is the vibration response of a structure obtained under conditions of natural operation. Diagnostics of the road bridge expansion joints has been carried out in order to identify characteristic dependences between the value of structure vibration response and types of expansion joint designs during the period of their operation while taking into account the features of the bridge structure. For this purpose, we have tested the methodology for collecting and processing data on the vibration response of the structure under natural conditions of its operation. The paper presents results of data collection on the coverage topology which have been obtained while using three-dimensional scanning method. Data collection on the vibration response of the structure has been carried out by measuring the vibration velocity and deformation of the structure. The data obtained are analyzed. As a result of testing and analysis of the obtained data, the main characteristics have been revealed: the value of base unevenness, the amplitude of vibration velocity and vibration displacement of the structure elements. Two main parameters of the dynamic impact have been assigned, adjusted for the mass of a moving vehicle, which can be used as main parameter for assessing the magnitude of the dynamic impact. A comprehensive method for assessing the dynamic impact on bridge structures has been developed and proposed in the paper, and its use will make it possible to differentiate various designs of expansion joints according to the magnitude of the dynamic impact of vehicles. This, in its turn, will contribute to formulate new recommendations on the use of specific types of expansion joints for various categories of highway, which will increase operational durability of expansion joints and the structure as a whole.

The analysis of vibrations in the vehicle with naturally aspirated and turbocharged gasoline engine

In this paper, the author presents a study of vibrations in a passenger vehicle and the possible influence on driver’s body in the process of natural operation. The author describes the dependence of engine size and additional equipment as the possible primary source of the vibration variations and their further propagation in the entire vehicle structure. The analysis was performed on the passenger cars with naturally aspirated and turbocharged gasoline engines. The aim of this study was to verify the level of vibrations in the vehicle structure with these particular engines, especially influence of downsized power unit, during various state of engine operation. The second goal was to examine the vibrations in the specified location related to driver’s body. The measuring method used piezoelectric accelerometers, which were attached to the designated locations in the vehicle and were able to detect variations of the acceleration. The signals were collected as characteristics in the time domain. In order to achieve frequency domain for spectral analyses, the author applied the Fast Fourier Transform (FFT).

Study of Degradation of Amorphous PV Module Performance under Different Climatic Conditions

Usually, manufacturers provide PV panels, accompanied with data measured under Standard Test Conditions (STC), i.e. determined at AM1.5 with an irradiance of 1000W/m2 and a cell temperature equal to 25 C. In fact, these conditions do not reflect the reality of natural operation of PV panel conditions and these functional data associated with the real panel operating point may vary from one environment to another due to the change in weather conditions. The characterization of different types of PV panels under natural conditions of operation is, therefore, necessary in order to have a global view about the true electrical performance of different technologies at a given site. This work evaluates the influence of climatic conditions on the behavior of QS-60DGF module which has been installed at the Unit of Research in Renewable energy URERMS Adrar in the southern Algeria. The degradation evaluation of QS-60DGF module with different defects was performed, using (I-V/P-V) characteristics under daily weather conditions and the the visual inspection such as glass breakag. This study is to investigate the degradation rates of a-Si PV module after more than one year of outdoor exposure in desert conditions.

Analysis of Velocity Pattern of a Power-Assisted Mobile Robot

This paper aims to analyze the velocity pattern of a power-assisted mobile robot when the operator performs operation without any discomfort. Power-assist systems for mobile robots such as wheelchairs and conveyance carriers are extremely effective in alleviating the physical burden on operators when they carry heavy objects. Although the velocity control based power-assist system has an advantage that it can be easily realized, the problem lies in that the system becomes unstable when the operator has high stiffness. Variable impedance control based on impedance estimation of the operator is effective at solving this problem. To realize operator impedance estimation, it is necessary to know the intended robot’s motion of a person. In this study, as a preliminary step to estimate the operator’s impedance, the velocity pattern when the operator performs natural operation of the robot through the power-assist system is analyzed. The results confirm that the natural velocity pattern can be approximated by a velocity pattern connecting two minimum jerk trajectories.

Gröbner–Shirshov bases for non-crystallographic Coxeter groups

For the group algebra of the finite non-crystallographic Coxeter group of type H 4, its Gröbner–Shirshov basis is constructed as well as the corresponding standard monomials, which describe explicitly all symmetries acting on the 120-cell and produce a natural operation table between the 14400 elements for the group.

Statistic of fuel consumption in test and in natural operation of vehicles

The lowering of carbon dioxide emission is world pursuit which is written in international agreement. It concerns all economy sections, especially motorization. In this last case the lowering is essential, since almost all fuel used for powering vehicles comes from nonrenewable resources. Using these fuels means a one-way carbon motion from underground lode to earth atmosphere. This process has to be immediately stopped. For several years there have been taken actions in this direction. There are both legislative and technical actions. However, the reports which were published in 2016 shows that despite the efforts and engagement of considerable means, the effects are mediocre. There has been noticed, that, though the lowering of carbon dioxide emission determined in bench tests has been attained, it is impossible to notice this progress in natural operation of vehicles. The causes of such a state are sought mainly in incompatibility of test conditions to the real operation of vehicles conditions. Assuming that the carbon dioxide emission is (quasi) directly proportional to fuel consumption, in the article there has been proposed the method of solving the problem of removing divergence between test and operational data. There has been suggested the different attitude to bench data analysis and implementation of new calculative procedures in a way to reach the correlation between the test and operating fuel consumption.

AN ANALYSIS OF THE WEAR OF PLOUGHSHARES WITH VARIOUS TECHNOLOGICAL SOLUTIONS

The paper analyses wear processes in various technological forms of ploughshares. Tests involved ploughshares made of Hardox 500, B 27 and 38GSA steel, as well as Hardox 500 steel with the cutting edges hardfaced by means of an El – Hard 63 electrode on the front and back sides, as well as 38GSA steel hardfaced by means of an EStelMn60 electrode. The tests were conducted during natural operation when processing sandy soil. During the tests, the changes in the mass and geometry of ploughshares were measured as a function of the processed area. Ploughshares made of steel were characterised by a diverse martensitic microstructure. The hardfaced layers, on the other hand, were dominated by chromium carbides with alloy ferrite. It has been concluded that the use of hardfaced layers considerably impact the decrease in the intensity of wear of the tested working elements. On the other hand, no significant differences were observed in the wear processes of hardfaced ploughshares depending on the native and additional material and the place of the application of the hardfacing agent. In the analysed soil conditions, ploughshares made of steel did not exhibit any significant differences in the wear process.

Polynomials Defined by Tableaux and Linear Recurrences

We show that several families of polynomials defined via fillings of diagrams satisfy linear recurrences under a natural operation on the shape of the diagram. We focus on key polynomials, (also known as Demazure characters), and Demazure atoms. The same technique can be applied to Hall-Littlewood polynomials and dual Grothendieck polynomials.The motivation behind this is that such recurrences are strongly connected with other nice properties, such as interpretations in terms of lattice points in polytopes and divided difference operators.