: This paper presents the authentication method using the Delaunay triangulation incremental algorithm and the Catalan objects. The proposed method is a combination of computational geometry and cryptography. This method presents a new step towards encoding the triangle coordinates using the Catalan-key. We provided specific suggestions for the application of this method in the authentication for bank clients by the image encryption. Client authentication verification is performed by asking the client to enter the (x,y) coordinate values of randomly selected indices of an array. If the entered coordinates match the index values in the banking system array, then the transaction or other operation is approved. If the matching fails, it means that we have an unidentified person who has followed the whole process and wants to break into the banking system. There are many advantages arising from a scenario for the user authentication by the assigned Catalan object and the stack permutation method. Also, we provided concrete examples for the Delaunay encryption of image with an authentication scenario and experimental results for the proposed method.

276 Erciyes Med J 2020; 42(3): 276–80 • DOI: 10.14744/etd.2020.86429 ORIGINAL ARTICLE – OPEN ACCESS This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. Edin Begic , Slobodan Obradovic , Slobodan Jankovic , Radoslav Romanovic , Nemanja Djenic , Boris Dzudovic , Zoran Jovic , Dragana Malovic , Vesna Subota , Milena Stavric , Farid Ljuca , Zumreta Kusljugic Increased High Sensitive C-reactive Protein is Associated with Major Adverse Cardiovascular Events after STEMI Objective: This study aims to investigate whether the high sensitive C-reactive protein (hsCRP) is associated with an ejection fraction of left ventricle (EFLV) in the early phase of ST-elevation myocardial infarction (STEMI), treated with the primary percutaneous intervention (pPCI), and to establish whether there exists a relationship between its values and the presence of major adverse cardiovascular events (MACE) within six months of pPCI. Materials and Methods: In this prospective study, 357 patients who were diagnosed with STEMI and who underwent pPCI within 24 hours of pain onset were included. The following were monitored and recorded: 1) hsCRP values, which were measured between 24 and 48 hours of pPCI, 2) EFLV values, which were measured five days after the pPCI, and 3) MACE, which was established within six months of pPCI. Results: The EFLV values measured five days after the pPCI were significantly lower with increasing hsCRP values (rho=0.384, p<0.0001). There was a significant difference in hsCRP values between patients who had MACE and those without it (38.35 [98.10] vs. 12.97 [23.80], p=0.0001). In addition, hsCRP values were significantly increased in patients who died during the first six months after the pPCI compared with patients who survived (115.00 [202.80] vs. 15.84 [31.5], p=0.001). Conclusion: The hsCRP values in patients with STEMI who were treated with the pPCI are related to systolic function in the early phase of STEMI, as well as MACE during the first six months of follow-up.

In general, polynomial difference equations and polynomial maps in the plane have been studied in both the real and complex domains (see [8, 9]). First results on quadratic polynomial difference equation have been obtained in [1, 2] but these results gave us only a part of the basins of attraction of equilibrium points and period-two solutions. In [4], the general second order difference equation is completely investigated and described the regions of initial conditions in the first quadrant for which all solutions tend to equilibrium points, period-two solutions, or the point at infinity, except for the case of infinitely many period-two solutions. In [3], case of infinitely many period-two solutions is completely investigated. Our results are based on the theorems which hold for monotone difference equations. Our principal tool is the theory of monotone maps, and in particular cooperative maps, which guarantee the existence and uniqueness of the stable and unstable invariant manifolds for the fixed points and periodic points (see [5]). Consider the difference equation

Good economy and high thermal efficiency of medium-speed diesel engines with direct fuel injection are very favourable characteristics in terms of energy conservation and combating global warming. Despite favourable fuel consumption and high efficiency, high emissions of nitrogen oxides (NOX) and particulate matter (PM) are a major problem researchers working on diesel engine development must address. Certainly the biggest challenge today is to make a compromise between optimal nitrogen oxide (NOX) and particulate matter (PM) emissions. Today, nitrogen oxide (NOX) reduction techniques are widely accepted and based on a combination of diluting in-cylinder air charge with a certain amount of exhaust gas, known as exhaust gas recirculation (EGR), and exhaust gas after-treatment using various sophisticated techniques. Results of the influence of the exhaust gas recirculation (EGR) on the emission of nitrogen oxides (NOX), obtained by experimental research on a medium-speed diesel engine are presented in this paper.

An autonomous underwater vehicle (AUV) or a multi-AUV system performing autonomous seafloor exploration missions by a side-scan sonar need to perceive their environment in order to replan the mission if they detect interesting objects in sensor data. Several anomalous/salient object detection methods mostly used for natural images are here applied to sonar images. All methods were firstly benchmarked on a 1500 simulated side-scan sonar images dataset. Precision-recall and processing time analysis was conducted in order to choose the best suited method in such controlled conditions. The performance of the best performing detection method was then validated on a 350 real side-scan sonar images dataset. This method was then implemented and optimized for the computer onboard an AUV. It turned out to be fast enough for online processing of large volumes of sonar data.

Mobile robots are increasingly becoming the subject of research and a very important area of science, so that the 21st century will be named as the century of development of service robots. Mobile robots are an excellent “System Engineering” research example because it includes a lot of scientific research, namely in the area of mechanical engineering, electrical engineering, electronics, computer science, social science, and more. As mobile robots perform their tasks in the same environment as humans, mobile robots should have the abilities that people have. The mobile robots should be able to recognize faces, gestures, signs, objects, speech and atmosphere. Successful realization set of tasks results in bypassing obstacles without collision and destruction in the shortest possible time and distance. They should communicate with people on the basis of emotion. The range of mobile robots application is huge. Mobile robots have found application in many areas, but this chapter will cover the following distribution of mobile robots areas of application: medicine, agriculture, defense, logistics, construction, demolition, professional cleaning, space exploration, education and scientific research. The price of robots is declining steadily and they are coming into ever wider use. It is only a matter of time before robots become available to the population of today's high school students, just as it happened with computers and cell phones.