Balkan Journal of Applied Mathematics and Informatics

APPLICATION OF GEOSTATISTICS IN THE ANLYSIS AND ADAPTATION OF GEOTECHNICAL PARAMETERS AT COAL DEPOSITS

Sun, 10 Dec 2023 00:00:00 +0000

This paper presents case study in application of geostatistics in the analysis and adaptation of a representative values on the geotechnical parameters at coal deposits. In order to select the most reliable geotechnical values for the design process of open cast pit excavations of large heights, different pools of laboratory data sets have been processed. The following critical geotechnical parameters had been investigated: volume weight, angle of internal friction, moisture content. By applying the correct geostatistical tools, and in comparison with practical experience and removal of obvious outliers from the datasets, for one of the deposit are prepared so called “geotechnical domains”, shown in the form of spatial distribution maps of the analyzed parameters. Advantages of the applied geostatistical approach are seen in enabling a higher confidence when performing slope stability analysis, selection of the most optimal geometry of the mines, lesser overburden quantities, protection of the environment, production cost cutting and time saving.

PROGRAMING PLC CONTROLLER WITH LADDER DIAGRAM

Darko Bogatinov, Saso Gelev — Sun, 10 Dec 2023 12:10:41 +0000

In this paper are consider one industrial process and consider about the automation of that industrial process. In automation the most important part is the controller. The controller is actually the brain of the process, and it regulates the switching on and off of all the elements involved in the process itself. The controllers that are used in industrial automation are called programmable logic controllers (PLC controllers). With example is showed how the PLC controller can be programed with Ladder Diagram. PLC programming involves creating a set of instructions that govern the behavior of a PLC to control machinery and processes. These instructions are written using specialized software tools and are executed in a sequential manner. The primary objectives of PLC programming are to ensure the safe and efficient operation of automated systems, maintain process accuracy, and facilitate quick responses to changing conditions.

Analysis of the usage of mobile devices as distributed tools for patient health monitoring and remote patient data acquisition

Dalibor Serafimovski, Stojce Recanoski, Aleksandar Krstev, Marija Serafimovska — Sun, 10 Dec 2023 00:00:00 +0000

The COVID-19 pandemic raised the need for telemedicine systems. Wearable and mobile devices are often a crucial part of those systems. In accordance with current research, this paper presents an analysis of some means, sensors and devices for remote patient health monitoring which can be combined together to form a complete patient health monitoring system. A few ways of measuring the health parameters are described. Focusing on the benefits offered by contemporary technology towards more complete use of telemedicine potential, this paper also reviews topics from the field of biomedical engineering.

RESEARCH ON INFLUENCE OF THE VOLUME OF OIL IN FRONT OF THE DIRECT OPERATED PRESSURE RELIEF VALVE TO ITS TRANSIENT PERFORMANCES

Sasko Dimitrov, Denis Weiler, Simeon Petrov — Sun, 10 Dec 2023 12:53:11 +0000

The dynamic characteristics determine variations of the inlet pressure in fornt of the valve in function of the flow through the valve in the time. In any hydraulic system, at valve inlet port there is some volume of compressible oil which influence the quality of the transient process. When switching the directional control valve in the hydraulic system with direct-operated pressure relief valves, a transient process occurs in which, depending of the amount of oil in front of the valve, it is possible for the pressure to reach values many times higher than the set value. This causes the system to be overloaded with undesirable consequences.

This paper examines experimentally and theoretically the influence of the volume of oil in front of the valve to its transient performances. It is presented that when there is low amount of oil in front of the valve, it reacts faster, but the system is significantly overloaded. When there is higher amount of oil in front of the valve, it reacts more slowly and overloads the system less above the preset value of the pressure.

IMPACT OF CUTTING CONDITIONS ON THE LOAD ON SERVO MOTORS AT A CNC LATHE IN THE PROCESS OF TURNING A CLUTCH HUB

Violeta Krcheva, Marija Cekerovska, Mishko Djidrov, Sasko Dimitrov — Sun, 10 Dec 2023 12:57:21 +0000

The purpose of the research in this paper is to investigate the impact of cutting conditions on the load on servo motors at a three-axis computer numerically controlled (CNC) Hitachi Seiki Seicos lathe. The analysed parameters (cutting speed, feed, and depth of cut) play a crucial role in the turning process. It is significant that each cutting condition directly alters the value of the load on the power system and has a significant effect on cutting forces, which in turn affect the load on the servo motors at the CNC lathe during the process.

REICH-TYPE CONTRACTIVE MAPPING INTO A COMPLETE METRIC SPACE AND CONTINUOUS, INJECTIVE AND SUBSEQUENTIALLY CONVERGENT MAPPING

Samoil Malcheski — Sun, 10 Dec 2023 12:59:10 +0000

In this paper, is given a generalization of the fixed point theorem of the Reich-type mapping on a complete metric space . Continuous, injective and sub-sequentially convergent mapping was used, as well as is taken that function is from the class continuous monotonically nondecreasing functions such that , where it is additionally assumed that it is subadditive, i.e. , for each .

GANTT CHART AS A PROJECT MANAGEMENT TOOL THAT REPRESENTS A CLUTCH HUB MANUFACTURING PROCESS

Violeta Krcheva, Mishko Djidrov, Sara Srebrenoska, Dejan Krstev — Sun, 10 Dec 2023 13:03:54 +0000

The purpose of the research in this paper is to present a clutch hub manufacturing process via Gantter, a Gantt chart-based project management software. The Gantt chart is one of the most used planning and controlling tools in project management today and can be called a main and very important tool of management. It allows the creation and edition of project plans through the implementation of defined activities, their durations, relationships between the activities, appropriate resources, and possible risks. This paper is an example that shows how the logic embedded in projects can be based on real manufacturing processes and applied to a project management tool in order to achieve the goals of the project.

ANALYSIS OF TOP SELLING PRODUCTS USING BUSINESS INTELLIGENCE

Tanja Stefanova, Zoran Zdravev, Aleksandar Velinov — Sun, 10 Dec 2023 13:08:02 +0000

Recently, there are three significant periods, which changed the world in almost all aspects – health, economy, education, travel and tourism, way of working, global cooperation, global energy crisis etc. Based on that, this paper analyses the top selling product in a company for each period, and presents their selling trend. The analysis was performed on a dataset from a company selling print services and products, using the concept of Business Intelligence, i.e. the powerful combination of Data Warehouse, ETL process and PowerBI. The results of the research confirmed that the announced periods made a significant impact on the world, businesses, and customer behavior. On the other side, the tools that we used in the research proved to be effective in transforming data and analyzing customer behavior.

ONE APPROACH TO THE ITERATIONS OF THE VEKUA EQUATION

Slagjana Brsakoska, Aleksa Malcheski — Sun, 10 Dec 2023 13:14:05 +0000

In this paper are given one old and one new approaches to the iterations of the Vekua equation in its most simple form. Some comparing is made and the conclusions are formulated as theorems.

CAN CHATGPT BE USED FOR SOLVING ORDINARY DIFFERENTIAL EQUATIONS

Sun, 10 Dec 2023 12:13:20 +0000

In this research we have conducted empirical study to evaluate the capabilities of OpenAI’s chat bot ChatGPT for automated software code generation and programming numerical methods for solving various types of differential equations. We have tested the ChatGPT for analytical as well as numerical solution of first and second order ordinary differential equations. Obtained results suggest that ChatGPT is a promising AI tool for programming numerical algorithms and solving differential equations. However, there are still some limitations and challenges of using AI for numerical solution generation, related to the potential biases in the algorithm, as well as need for large amount of high-quality training data. However, as AI technology continues to develop, it is likely that the use of AI for programming will become more prevalent and effective in the future.

SEIR MODEL OF TUBERCULOSIS

Sun, 10 Dec 2023 13:16:26 +0000

Tuberculosis (TB) is a highly contagious infectious disease caused by the bacterium Mycobacterium tuberculosis. It primarily affects the lungs but can also affect other parts of the body. TB poses a significant global health burden, with millions of new cases and deaths reported each year. Understanding the spread of tuberculosis and evaluating control measures are crucial for effective disease management. The SEIR model is a commonly used mathematical framework for studying the spread of infectious diseases. It divides the population into four compartments: Susceptible (S), Exposed (E), Infectious (I), and Recovered (R). In the case of tuberculosis, an additional compartment for the number of deaths (D) is included. The model tracks the flow of individuals between these compartments over time.

APPLICATION OF LAPLACE TRANSFORM IN ELECTRICAL CIRCUITS

Jasmina Veta Buralieva, Maja Kukuseva Paneva — Sun, 10 Dec 2023 13:18:05 +0000

In the present paper the application of Laplace transform and its inverse transform, for solving ordinary differential equation with constant coefficients and initial condition is considered. The solution of ordinary differential equation that describes serial RLC circuit is provided. Some results of the simulations are also given.

ABOUT A CLASS OF 2D MATRIX OF DIFFERENTIAL EQUATIONS

Biljana Zlatanovska, Boro Piperevski — Sun, 10 Dec 2023 13:19:54 +0000

A class of 2D matrix dierential equations and their connection to
second-order dierential equations with polynomial coefficients are considered.
By using the method of transformation, appropriate results for their correlation
are obtained. These results enable obtaining appropriate conditions for the
integrability of one of the classes and systems of dierential equations.The theory
is supported by examples.

BIOTECHNOLOGICAL PROCEDURE FOR AN AUTOLOGOUS DENTIN GRAFT FOR DENTAL AND MEDICAL PURPOSES

Sun, 10 Dec 2023 12:40:36 +0000

Teeth that have been extracted are still regarded as clinical waste and are therefore not deemed useable. An autologous dentine graft is currently produced from extracted teeth using the SDG, a specialized equipment. The aim is to present a new protocol and new method for getting a mineralized autologous dentine graft from recently extracted teeth. In this paper, the method is applied to maintaining the alveolar ridge and has the potential to be used to fill in defects in the jawbones and the entire skeleton system. Autologous dentin graft (ADG) has strong potential for repairing bone and soft tissue components in the jawbones while retaining the alveolar ridge's vertical and horizontal dimensions is another goal of the study. It was done using a device known as a Smart Dentin Grinder (SDG), which only needs three seconds to grind the extracted tooth into dentin grains that range in size from 300 to 1000. With the aid of the chemical reagents employed, the produced dentine particles go through chemical processing. The complete treatment was carried out in accordance with Itzh ak Binderman's (2014) protocol. The obtained ADG is a enough quantity of solid, pure graft material for use in oral surgical operations. It is put to use right away and is more patient-friendly financially. Due to its potential for osteogenetic, osteoinductive, and osteoconductive properties, dentin particles employed as graft material need to be regarded as the gold standard. In several areas of medicine and dentistry, directed bone regeneration can be carried out using the acquired and prepared ADG.

COMPARATIVE ANALYSIS BETWEEN BIFACIAL AND MONOFACIAL SOLAR PANELS USING PV*SOL SOFTWARE

MLADEN MITKOVSKI , VLATKO CHINGOSKI — Sun, 10 Dec 2023 12:42:30 +0000

Traditional solar panels commonly used in today’s solar power projects are monofacial i.e., with solar cells only on one side of the panels. Recently, many solar panel producers have improved their panel designs by introducing so-called bifacial solar panels which feature solar cells on both sides of the solar panel. Producers claim that the bifacial solar panels, regarding energy generation, typically overperforms the traditional monofacial solar panels by about 5.5%, with additional investment cost between 10% and 25%, which strongly depends on the producer and the size of the project.

In this paper, the authors made a simulation and comparative analysis between bifacial and monofacial solar panels using PV*SOL simulation software. The simulation was done on a solar power project with an installed capacity of 1 MW using exact solar insolation values for the exact geographical location. Typical bifacial and monofacial half-cell solar panels available at the local market were used for the analysis. For enhancing the analysis, two common placements of the panels were utilized, ground placement, and rooftop placement parallel with the roof at the same inclination (pitch) and orientation (azimuth). Obtained results using PV*SOL simulation software for both panels and both placements are presented with accompanying discussion. For ground placement, bifacial solar panels resulted in increased energy generation of approximately 2.5%, while for rooftop placements the amount of the increased energy generation was negligible. Ground-placed bifacial solar panels have increased energy generation all year around, while rooftop bifacial solar panels provide larger energy generation only during summer months, from June to August. For the rest of the year the energy generation difference, although in favor of bifacial over monofacial solar panels, was still negligible.

ANALYSIS OF DEVELOPING NATIVE ANDROID APPLICATIONS USING XML AND JETPACK COMPOSE

Egzon Milla, Milutin Radonjić — Sun, 10 Dec 2023 12:43:45 +0000

Native mobile applications have been the first choice for companies and independent developers to build software that utilizes device hardware and functionality. For Android development, this means using Java/Kotlin for the program logic and XML files for the user interfaces. Recently, Jetpack Compose has gained significant attention in building user interfaces for Android applications. This paper aims to analyze the benefits and limitations of these two technologies. An intensive literature review is conducted and presented to identify the benefits and limitations of XML and Jetpack Compose. In order to compare their development processes and code complexity, we also developed the same application using both technologies. Analysis of the code used in each technology provides an insight into how they uniquely solve the same problem, helping us to identify which one is better suited from a developer’s perspective. The results of the study indicate that both XML and Jetpack Compose have their respective strengths and weaknesses. XML provides a structured approach to UI development, fully respecting the separation of concerns between the view (what is being displayed on the screen) and the controller (which data is being sent to the view). On the other hand, Jetpack Compose simplifies the UI development process by offering a declarative approach, which leads to more readable and maintainable code. This study identified the advantages and disadvantages of using XML and Jetpack Compose in the development of native Android applications and recommended criteria for choosing one of these tools for new users, as well as switching to a new tool for experienced users.

TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION METHOD IN PATIENTS WITH XEROSTOMIA

Sun, 10 Dec 2023 12:45:25 +0000

Patients with salivary gland hypofunction typically complain of dry mouth, difficulty chewing, swallowing and/or speaking; they hardly tolerate spicy, acidic, and crunchy food and often times report taste changes or difficulty wearing dentures. It can also increase the chance of developing dental decay, demineralization of teeth, tooth sensitivity, and oral infections. The goals of treating xerostomia include identifying the possible causes, relieving discomfort, and preventing complications. . In this study, we investigate the most effective frequency to increase salivary secretion, without side effects on the skin and orofacial structures. Transcutaneous electric nerve stimulation (TENS) is a simple, inexpensive, and non-invasive modality that uses electric current to activate nerves for therapeutic reasons. It is a non-pharmacological method of pain management for which it is widely used. Application of electric impulses to one or more of the three components of the salivary reflex arch should theoretically improve salivary secretion and lessen the various long-term effects of hyposalivation. For this study were analyzed totally 23 published studies in the last 10 years. The study is made on narrative review of published articles that were go into the related subject, evaluation of the impact of a transcutaneous electrical nerve stimulation (TENS) system on patients' dry mouth and salivary flow rates. The TENS unit was effective in increasing the quantity of stimulated saliva and was also found to be more effective in increasing saliva in diabetic individuals. From the results of the study, it can be concluded that TENS was effective in increasing the salivary flow rate in hyposalivatory patients with residual saliva.

COMPARATIVE ANALYSIS OF STANDARDS AND METHODOLOGIES FOR MANAGEMENT OF INFORMATION-SECURITY RISKS OF TECHNICAL AND ELECTRONIC SYSTEMS OF THE CRITICAL INFRASTRUCTURE

Marjan Zafirovski, Dimitar Bogatinov — Sun, 10 Dec 2023 12:46:26 +0000

Information security is a priority at the national and world level, which results with the need to define certain security violations with the ultimate goal of successfully preventing information breaches, and with that quickly and successfully remediating the consequences.

In a cyber-war scenario, the energy and financial sectors are considered as the most critical to national security. The identification of key weaknesses, risks and potential exposure to cyber threats in energy systems, as well as the creators of cyber incidents, can be performed based on the perception of possible cyber-attack scenarios.

At the world level, there are several models for assessing and managing security risk (ISO/IEC 27001, NIST 800-53, COBIT, OCTAVE Allegro, etc.) and therefore the main goal of this research is to sublimate and compare the values of the most frequently used methodologies, which will enable the selection of the best model for the successful prevention of information breaches and the quick and successful remediation of the consequences.

This paper will analyze the application of current standards and methodologies for managing information-security risks in the elements of CI, assessment of the level of application of standards and methodologies in the institutions, which are part of CI, as well as determining a way to improve the management of current information security risks.