Multi-robot Automated Search for Non-Adversarial Moving Evaders in an Unknown Environment

In this paper, the problem of searching for moving evaders in unknown environment using group of mobile robots is investigated. The aim is to find the moving evaders as fast as possible. Three different search techniques are proposed and evaluated through extensive experimentation. In the first two techniques, robots do not cooperate or coordinate their actions. Alternatively, they implement simple movement strategies to locate the evaders. On the contrary, in the third technique, robots employ explicit coordination among each other and they implement a relatively complex algorithm based on voronio graph to find the evaders. In the later technique, each robot needs to be equipped with communication and localization capabilities. The results showed that graph-based technique led to shortest search time. However, it also showed that a reasonable performance is possible with cheap robots implementing simple and non-coordination techniques. Keywords: Search, Multi-Robot, Voronio Graph, Moving Target, Coordination

Koordinacija više robota za učinkovite pretraživanje prostora

This paper addresses the problem of exploration of an unknown environment by developing effective exploration strategies for a team of mobile robots equipped with continuously rotating 3D scanners. The main aim of the new strategies is to reduce the exploration time of unknown environment. Unlike most of other published works, to save time, the laser scanners rotate and scan the environment while robots are in motion. Furthermore, the new strategies are able to explore large outdoor environments as a considerable reduction of the required computations, especially those required for path planning, have been achieved. Moreover, another new exploration strategy has been developed so that robots continuously replan the order to visit the remaining unexplored areas according to the new data (i.e. updated map) collected by the robot in question or by the other team members. This new extension led to further enhancements over the above mentioned ones, but with slightly higher computational costs. Finally, to assess our new exploration strategies with different levels of environment complexity, new set of experiments were conducted in environments where obstacles are distributed according to the Hilbert curve. The results of these experiments show the effectiveness of the proposed technique to effectively distribute the robots over the environment. More importantly, we show how the optimal number of robots is related to the environment complexity.Ovaj članak istražuje problem pretraživanja nepoznatog prostora razvijanjem učinkovite strategije za tim mobilnih robota s rotirajućim 3D laserskim senzorom. Glavni cilj ove nove strategije je smanjenje vremena pretraživanja nepoznatog prostora. Za razliku od većine objavljenih radova, u ovome članku, radi smanjenja vremena, laserski senzori rotiraju i snimaju prostor dok su roboti još u pokretu. Predložene strategije, pošto se njima znatno smanjuje računska složenost, pogotovo za planiranje gibanja, omogućuju pretraživanje i vanjskih prostora prostora velikih dimenzija. Nadalje, razvijena je još jedna strategija pretraživanja koja omogućuje robotima da kontinuirano replaniraju poredak kojim će posjetiti ostatak neistraženog prostora, prema novim podacima (ažuriranoj karti) prikupljenim od njih samih ili drugih članova tima. Ovo novo proširenje nadalje unaprjeđuje performanse algoritma, ali uz nešto veću računsku složenost. Kako bi se u konačnici testirale nove strategije pretraživanja na prostorima različite složenosti, provedeni su eksperimenti s preprekama raspoređenim po Hilbertovoj krivulji. Rezultati eksperimenata pokazuju učinkovitost predložene metode u prostornom raspoređivanju robota. Od posebne je važnosti istaknuti da se u članku također istražuje odnos između broja robota i kompleksnosti prostora

Strengths, Weaknesses & The Potential Opportunities for The Employing Informatics in The Jordanian University Education from Education Colleges’ Students’ Perspective

Abstract  The study aimed to identify the extent of employing informatics in the Jordanian university education from Education Colleges’ students’ perspective according to informatics resources, informatics software programs and informatics devices and to identify the strong and weak aspects in the reality, in addition to  the possible opportunities and threats. Moreover, the study aimed to reveal the differences in the respondents’ responses about employing informatics in the Jordanian university education according to gender and university variables. The sample of the study consisted of 150 students representing Education Colleges’ students in three Jordanian universities ( University of Jordan, Balqa Applied University, AL-Bayt University).  To achieve the study’s goals , the researchers adopted the descriptive approach and SWOT analysis.The most significant results were as follows :1) The level of employing informatics in the Jordanian university education was moderate with (62.7%). And the field of informatics devices came in the first rank followed respectively by the fields of informatics software and informatics resources.2) There were statistically significant differences in the respondents’ responses about employing informatics in the Jordanian university education attributed to the variables : gender in favor of the male students and the university in favor of Balqa Applied University.3) There were aspects of strength in employing informatics as : understanding the use of Internet to keep up with the latest publications in information. There were aspects of weakness in employing informatics as: lack of exchanging information with the professors through the e-blogs. Additionally, one of the possible  opportunities in employing informatics in the Jordanian university education is  the possible use of the electronic browsers in developing the scientific research skills.In light of these results, the study recommended the necessity to develop , prepare and provide  the infrastructure of  technical informatics  in the Jordanian universities and to increase the interest of the real needs of the university informatics environment, in addition to the necessity of having a suitable strategy for employing the informatics in the Jordanian university education within the university’s whole strategy and following up its implementation and evaluation so as to achieve the university’s vision and its goals

A proposed cloud-based billers hub using secured e-payments system

Automation of several payment processes from start to end is a challenging task, particularly when multiple payments from online and offline billers are involved. In this paper, we introduced a new aggregator system to combine all billing system types, in which it is possible to pay invoices electronically. The proposed aggregator system was designed to be employed in a cloud-based Billers Hub (CBBH) developed by the central banks. Furthermore, many applications can be realized such as; deposit e-money, withdrawal e-money, and other applications. A Gateway translator is used to apply authentication rules, security, and privacy. The proposed system was employed in the Jordanian payment gateway and successfully fulfills its purpose

Resonance Mode Acoustic Displacement Transducer

Several linear displacement transducers are used in industry and many technical applications. In this research, a linear displacement transducer which uses a standing acoustic wave within a tube with variable length is designed, built and tested. A standard PC will be utilized for data processing and storage. The operation principle of this transducer is based measuring the resonance frequency of the created standing acoustic within tube. A relationship between the tube length and the measured frequency is determined. Besides to design and build of a measurement system for this transducer, three models of transducer prototype will be tested to study the effect of ambient temperature and diameter of the tube on resulting measured frequency

Exploration Algorithm Technique for Multi-Robot Collaboration

ABSTRACT: This paper focuses on wall-following exploration algorithm using two cooperating mobile robots. The aim is to decrease the exploration time and energy consumption. The new technique is a combination of wall-following exploration algorithm and frontier-based exploration algorithm. The proposed algorithm is divided into two stages: Firstly, one of the robots follows (detects) the entire of the environment walls. And secondly, they employ frontier-based algorithm to complete exploring the remaining unexplored areas in the environment. During these two stages, the robots sweep the lineof-sight between them in each step to maximize the exploration efficiency. Numbers of simulation experiments are presented. Moreover, testing with real robots will be introduced. In these experiments, the negatives and shortcomings of this exploration algorithm will be overcome

The impact of nephrostomy balloon inflation volume on post percutaneous nephrolithotomy hemorrhage

Introduction: the study aims to match different volumes of nephrostomy balloon inflation to point out the foremost effective volume size of post percutaneous nephrolithotomy (PCNL) bleeding control. Methods: we have retrospectively reviewed “560” medical records of patients who underwent percutaneous nephrolithotomy between (the years 2017 and 2018) at Prince Hussein Urology Center. The Patients were divided into two teams, group-1 (a number of 280 patients) with nephrostomy balloon inflated concerning three ml and group-2 (a number of 280 patients) the balloon inflated concerning one ml. The preoperative and postoperative hematocrit, the operation duration, the stone size, the postoperative pain severity, the transfusion rate and the duration of hematuria between the two groups were compared during hospitalization. Results: regarding patients with ages (between 18 and 68 years); the preoperative hematocrit (mean values ± SDs) was (40.35% ± 3.57) vs (39.95% ± 3.43) for groups-1 and 2, respectively; the p value=0.066. The postoperative hematocrit was (37.91% ± 3.96) vs (34.38 ± 2.78), respectively; the p value was (0.008); the blood transfusion rate was 11.2% vs 13.4% (the p value was 0.039), respectively. The Postoperative pain score was (4.93 ± 1.44) vs (3.89 ± 1.45) (the p value was 0.012), respectively. Conclusion: increasing the nephrostomy balloon volume to a “3cc” competes for a task to decrease bleeding which was found to be as a secure and considerable effective procedure-related factor. However, the disadvantage of this technique resulted in increasing the postoperative pain in patients undergoing such a procedure