Epidemiological models play an important role in the study of diseases. These models belong to population dynamics models and can be characterized with differential equations. In this paper we focus our attention on two epidemic models for malaria spreading, namely Ross-, and extended Ross model. As both the continous and the corresponding numerical models should preserve the basic qualitative properties of the phenomenon, we paid special attention to its examination, and proved their invariance with reference to the data set. Moreover, existence and uniqueness of equilibrium points for both models of malaria are considered. We demonstrate the theoritical results with numerical simulations.
This article is a research on the effect of material segregations due to squeeze parameters on mechanical properties of high pressure die cast parts. The technology of squeezing is applied in high pressure die casting technology with the aim to improve the internal material health of the castings from aluminium alloys, such as AlSi9Cu3(Fe), components incorporated in assemblies as mechanical and hydraulic parts. The objective of this article is to determinate the influence of the secondary effects of squeeze technology on the mechanical properties of parts produced from AlSi9Cu3(Fe) alloys, with HPDC technology.
This paper deals with the design of metamaterial (MTM) substrates to be used in electromagnetic devices. In particular, the approach has been considered for different investigations having the scope the realization of antennas on flexible substrates. The importance of the topic resides in the potential of conforming the antenna to/on desirable shapes. Flexibility is well exploitable either in advanced communication systems or in biomedical applications, just to mention some. The proposed MTM is made of metallic spherical inclusions of AISI52100, which are embedded in a polymer host. The paper aims to assess the feasibility of increasing the performance of a microstrip patch antenna, and to decrease its size by using the MTM substrate, which is able to locally control the permittivity of the substrate and to create electromagnetic band-gap regions outside of the patch.
The efficient human-machine interaction is an essential and current problem of computer science. The paper presents a gesture recognition method which applies optical flow calculation and an aggregation for obtaining a heatmap-like representation of the motion trajectories. After the overview of the image processing workflow, the paper introduces six symbols for providing some measurements. The described experiments show the robustness of the method against color, shape and time variance.
This paper reports the research results on the target group survey at European level, composed of manufacturing SMEs and VET regarding knowledge and skills gaps about Industry 4.0, namely knowledge and skills gaps. It sets the basis for elaboration of the of a training course and a practical methodology for web based learning in accordance with the target groups’ needs as well as to provide basis for forming recommendations for evidencebased policy in the field of web based learning. The suggested training modules are: Introduction to Industry 4.0; Solutions for smart production environments in the manufacturing sector; Smart robotics; and Application of CPS/IoT across the process chain. The preferences according to the technological solutions/functions in an interactive educational website are highlighted as well as the proportion of theory and practical on the job training when organizing web based learning in the field of Industry 4.0.
This paper aims to mirror the way the European Professors of Industrial Engineering and Management (EPIEM)network perceives itself with a students’ view. Along with a presentation of the status quo of the EPIEM network, a brief survey among students is deployed to get an impression of the perception of EPIEM by its most active partner association - the European Students of Industrial Engineering and Management (ESTIEM). The explorative findings (i) provide insights into the current situation of EPIEM from an inside and outside perspective and (ii) deliver ideas for the future development of the EPIEM network. With regard to the relationship management practice between EPIEM and ESTIEM this research represents an innovative approach within the European IEM organizations.
Hundreds of millions of people around the world spend almost a third of their day at work. Many of them are dissatisfied with the climatic conditions in which they work, being exposed to various risks of heat or cold. The most common reasons for dissatisfaction are elements related to IAQ (Indoor Air Quality), in other words, thermal comfort and air quality inside the buildings. Thus, the assessment of the microclimate in the workplace is very important, and the IAQ indicators play a decisive role in the mental and physical capabilities. This writting wants to identify for the area of Mures county how many of the managers of the production halls with microclimate with heat release, where the workers are exposed to stress because of the heat, are aware of these elements and give them the proper importance.
This paper presents fault detection techniques, especially the motor current signature analysis (MCSA) which consists of the phase current measurement of the electrical motor’s stator and/or rotor. The motor current signature analysis consists in determining the frequency spectrum (FFT) of the stator current signal and evaluating the relative amplitude of the current harmonics. Sideband frequencies appear in the frequency spectrum of the current, corresponding to each fault. The broken bar is a frequent fault in induction motors with squirrel-cage rotor. It is presented the equivalent circuit for induction motors and the equivalence between the squirrel-cage rotor and the rotor windings. It is also presented an equivalent circuit model for induction motors with squirrel cage rotor, and based on this a Simulink model was developed. It is shown how a broken rotor bar influences the magnetic field around the rotor and through this the stator current. This modification is highlighted through the developed model.