Prediction Model of the Resulting Dimensions of Welded Stamped Parts

The combination of stamping and subsequent welding of components is an important area of the automotive industry. Stamping inaccuracies affect the final size of the stamping and the welded part. In this article, we deal with a specific component that is produced by such a procedure and is also a common part of the geometry of a car. We focused on the possibility of using a negative phenomenon—deformation during welding—on the partial elimination of inaccuracies arising during stamping. Based on the planned experiment, we created a prediction model for the selected part and its production, with the help of which it is possible to determine suitable welding parameters for a specific dimension of the stamping and the required monitored dimension of the welded part. The article also includes the results of additional experimental measurements verifying the accuracy of the model and prediction maps for practice.

Combinatorial QFT and the Jacobian Conjecture

The Jacobian Conjecture states that any complex n-dimensional locally invertible polynomial system is globally invertible with polynomial inverse. In 1982, Bass et al. proved an important reduction theorem stating that the conjecture is true for any degree of the polynomial system if it is true in degree three. This degree reduction is obtained with the price of increasing the dimension n. We show in this chapter a result concerning partial elimination of variables, which implies a reduction of the generic case to the quadratic one. The price to pay is the introduction of a supplementary parameter 0≤n′≤n, parameter which represents the dimension of a linear subspace where some particular conditions on the system must hold. We exhibit a proof, in a QFT formulation, using the intermediate field method exposed in Chapter 3.

Optimization Mathematical Model of the Distribution of Tasks and Labor Resources in the Enterprise

In article one of aspects of a solution of the problem of improvement of management is considered. Effective management is based on optimum use of resources and competent complex assessment of the organization. The modern IT market offers ON, capable to automate activity of any enterprise by full or partial elimination of a human factor. However in the companies where the overall performance is characterized by use of human resources, everything is not so simple. The research of authors is devoted to modeling of process of distribution of tasks and human resources by mathematical methods and combinatory optimization of process of distribution of tasks between employees within the company.

SARS-CoV-2 as Enteric Virus in Wastewater: Which Risk on the Environment and Human Behavior?

Microorganisms such as viruses, bacteria, and protozoa are the cause of many waterborne human infections. These microbes are either naturally present in aquatic environments or transferred within them by fecal sources. They remain in these environments for varying lengths of time before contaminating a new host. With the emergence of the COVID-19 pandemic, some studies have reported the presence of viral nucleic acids in stool samples from COVID-19 patients, suggesting the possibility of fecal-oral transmission. The SARS-CoV-2 RNA was thereby detected in the wastewater of symptomatic and asymptomatic people with a risk to human and environmental health. In this work, we try to discuss the different potential sources of this contamination, the forms of persistence in the environment, the techniques of partial elimination, and the possibility of creating new reservoirs.

SARS-CoV-2: Remarks on the COVID-19 Pandemic

The COVID-19 pandemic developing rapidly in 2020 is triggered by the emergence of a new human virus—SARS-CoV-2. The emergence of a new virus is not an unexpected phenomenon and has been predicted for many years. Since the virus has spread all over the world, it will be very difficult or even impossible to eradicate it. A necessary condition for complete or partial elimination of the virus is to have an effective vaccine. It is possible that SARS-CoV-2 will become milder in the next few years and COVID-19 will then only threaten individuals from risk groups.

The Issue of Shunting of the Affected Phase in Compensated Medium Voltage Networks

<p class="TEEAbstract">Permanently increasing size of the capacitive currents in medium voltage networks becomes a limiting factor in their operation. This negative trend is manifested especially in the mixed networks, where the proportion of cable gradually increases in comparison with the overhead medium voltage lines. The residual currents in the one-pole insulation faults in the medium voltage system, in insulation fault site are continually increasing. Large investment funds are necessary for full elimination of the fault currents, while other known ways used in the partial elimination of the size of the fault currents have some technical limitations. In this article, the positive and negative sides of the method “Shunting of the affected phase in compensated medium voltage networks” are then evaluated.</p>

Taxonomic Composition and Population Level of the Prosthetic Bed Mucosa Microbiota in Case of Dentition Defects in Patients Wearing Partial Dentures

The article considers the taxonomic composition and the population level of the oral cavity microbiota and changes in their characteristics after prosthetic rehabilitation with partial removable dentures. In the patients with partial loss of teeth wearing conventional removable dentures, the taxonomic composition of the gingiva microbiota changes due to the biotope contamination with opportunistic S. aureus and yeast-like fungi of the Candida genus, S. haemolyticus, K. pneumoniae, enterobacteria (E.coli, K.pneumoniae, E.cloacae), B.catarralis, M.lacunata and partial elimination of S. sialivarius, S.sanguis, S. mutans, S. mitis from the biota. The objective of the research was to study changes in the gingiva in the examined patients. Materials and Methods. Microbiological (bacteriological and mycotic) examination of gum mucus secretion in the patients with partial loss of teeth was performed. The control group consisted of 50 (23 men and 27 women) patients without any infectious and noncommunicable diseases, who had no problems adapting to removable denture during the last 6 months. Results and Discussion. In 78.72% of the patients, microorganisms isolated and identified from the surface of the prosthetic bed, were in associations that consisted of 2 (31.70%), 3 (8.51%) and 4 (8.51 %) taxons. The most numerous associations consisting of 2 taxons were: S. aureus and M. lacunata; S. aureus and N. flavescens; S. haemolyticus and B.catarrhalis as well as C. albicans and S. epidermidis. In the biotope (the surface of the gum mucosa of the prosthetic bed) of the patients wearing partial removable laminar dentures, the population level reduced in S. salivarius, S. sanguis, S. mutans, S. mitis and significantly increased in opportunistic staphylococci (S. aureus, S. haemolyties, S. epidermidis), S. pyogenes, enterobacteria (E. coli, K. pneumoniae, E. clocacae), B.catarrhalis. Microorganisms S. aureus and C. albicans reached a high population level; it increased in S. haemoliticus, S. epidermidis, S. pyogenes, E. coli, E. cloacae, K. pneumoniae as well. Conclusions. In the patients with partial loss of teeth wearing conventional removable dentures, the taxonomic composition of the gingiva microbiota changed due to the contamination of the habitat with opportunistic S. aureus and yeast-like fungi of the Candida genus, S. haemolyticus, K. pneumoniae, enterobacteria (E .coli, K. pneumoniae, E. cloacae), B. catarralis, M. lacunata and partial elimination of S. sialivarius, S.sanguis, S. mutans, S. mitis from the biota.