Michał Maćkowski

The Concept of Using Multi-protocol Nodes in Real-Time Distributed Systems for Increasing Communication Reliability

The paper presents the considerations on the method which enables to accelerate the exchange of data in distributed control system, using multi-protocol nodes. The method presented in this paper is related to hardware and software, and based on new original communication protocol, which is used by the node for supporting various communication protocols to simultaneous data exchange via different buses. This method will enable to increase not only network bandwidth, but also the security of data transmission.

Reliability of Bluetooth Smart Technology for Indoor Localization System

The main objective of the paper was to test whether the devices compatible with Bluetooth Low Energy are reliable for indoor localization system. To determine the reliability of this technology several tests were performed to check if measured distance between Bluetooth transmitter and mobile device is close to the real value. Distance measurement focused on Bluetooth technology based mainly on received signal strength indicator (RSSI), which is used to calculate the distance between a transmitter and a receiver. As the research results show, the Bluetooth LE signal power cannot be the only reliable source of information for precise indoor localization.

An Approach to Control of Human Leg Switched Dynamics

This article describes the approach to control of human leg dynamical model as a switched linear system. The control scheme consists of fractional and integral order PID controllers. In the paper we analyze the responses of the system depending on the above-mentioned controllers. We focus our attention on angular displacements only. The angular velocity maybe arbitrary. Additionally, we present the method how to design a human leg as the switched linear system. In this case the switching rule is state-dependent. Finally, we present two illustrative examples for two different trajectories.

The Analysis of Microprocessor Instruction Cycle

Each microcontroller realizing the code saved in a program memory emits electromagnetic disturbances, both conducted that propagate through lines connected to the processor and radiated in the form of electromagnetic field. All of these undesirable signals emitted by the processor can be measured, received and interpreted by the appropriate methods. However, this subject requires a precise measurement and understanding of processes occurring inside the microprocessor during realization of the sequential instructions. The presented results of the influence of parameters such as data bus state, instruction argument, the result of operation on the voltage waveform on the power supply lines of microprocessor, enable to understand the processes occurring during the realization of following instructions by microprocessor unit.

Electromagnetic Emission Measurement of Microprocessor Units

Each microcontroller realizing the code saved in a program memory emits electromagnetic disturbances both conducted, that propagate through lines connected to the processor, and radiated in the form of electromagnetic field. All of these undesirable signals emitted by the processor can be measured, received and interpreted by the appropriate methods.

Tutoring math platform accessible for visually impaired people

BACKGROUND There are many problems with teaching and assessing impaired students in higher education, especially in technical science, where the knowledge is represented mostly by structural information like: math formulae, charts, graphs, etc. Developing e-learning platform for distance education solves this problem only partially due to the lack of accessibility for the blind. METHOD The proposed method is based on the decomposition of the typical mathematical exercise into a sequence of elementary sub-exercises. This allows for interactive resolving of math exercises and assessment of the correctness of exercise solutions at every stage. The presented methods were prepared and evaluated by visually impaired people and students. RESULTS The article presents the accessible interactive tutoring platform for math teaching and assessment, and experience in exploring it. The results of conducted research confirm good understanding of math formulae described according to elaborated rules. Regardless of the level of complexity of the math formulae the level of math formulae understanding is higher for alternative structural description. CONCLUSIONS The proposed solution enables alternative descriptions of math formulae. Based on the research results, the tool for computer-aided interactive learning of mathematics adapted to the needs of the blind has been designed, implemented and deployed as a platform for on-site and online and distance learning. The designed solution can be very helpful in overcoming many barriers that occur while teaching impaired students.

Instruction Prediction in Microprocessor Unit Based on Power Supply Line

This paper illustrates the research results concerning the character of signals emitted by the selected microcontroller via the power supply lines. The main purpose of the study is to determinate the instruction that is currently realized by the microprocessor, based on the conducted emission in the power supply lines.

Automatic Scenario Selection of Cyclic Exchanges in Transmission via Two Buses

The paper presents the theoretical and empirical tests which examine the algorithms of automatic scenario selection of cyclic exchange in transmission via two buses. The implemented method is the base for using the second (redundant) bus for data transmission. The main aim of this method is to build two-stream data transmission so that each data stream has similar, or even the same transmission time. The flexibility of the proposed solution results from the fact that it is useful not only for two-bus transmission, but also when the transmission is via only one bus. This method allows estimating the time of the network cycle and also indicates the values of the times for acyclic transmissions. The presented method is only the introduction to designing, developing and controlling the two-stream transmission.

Influence of Electromagnetic Disturbances on Multi-network Interface Node

The main idea presented in the paper focuses on testing behavior of multi-network interface node while electromagnetic disturbances in transmission line occur. Such node is able to unload an increased traffic in network or provide the security of transmission, especially in cases of temporary overloads, system failure – damage of transmission system, or events occurring in industry area. The authors marked the potential possibilities of using equipment for EMC (Electromagnetic Compatibility) measurements in the process of testing and simulating the real threats (disturbances) that may appear in the object. The final results point out the correct work of developed query distributor system and the opportunities of automatic adjustment of the network topology in case of electromagnetic disturbances.

Instruction Prediction in Microprocessor Unit

Protection of computer systems from an unauthorized access to the classified information is a very essential issue. The research deals with some aspect of this problem resulting from the fact, that for instance, an author of a software for embedded system is not aware that it is possible to identify partly or entirely, program code. It can be done in non-invasive way, without influence on the microprocessor internal structure and program memory. The authors intend to prove that it is possible to recognise the instructions executing by certain type of microprocessor, analysing only the character of disturbances in the power supply lines. The research results inspire to the more careful study of ways and methodology for developing software, which should highly hinder the software reverse engineering.