Data Science: Journal of Computing and Applied Informatics <p align="justify"><span class="" lang="en"><span class="">Data Science: Journal of Computing and Applied Informatics (JoCAI) is a peer-reviewed biannual journal (January and July) published by TALENTA Publisher and organized by Faculty of Computer Science and Information Technology, Universitas Sumatera Utara (USU) as an open access journal. It welcomes full research articles in the field of Computing and Applied Informatics related to Data Science from the following subject area: Analytics, Artificial Intelligence, Bioinformatics, Big Data, Computational Linguistics, Cryptography, Data Mining, Data Warehouse, E-Commerce, E-Government, E-Health, Internet of Things, Information Theory, Information Security, Machine Learning, Multimedia &amp; Image Processing, Software Engineering, Socio Informatics, and Wireless &amp; Mobile Computing. <br></span></span><span class="" lang="en"><span class="">Each publication contains 5 (five) research articles which will be published online. These articles are indexed by&nbsp;<a href="">Indonesian Publication Index (Garuda Portal)</a>, <a href=";repository_id=6638">One Search Perpustakaan Nasional</a>,&nbsp;<a href=";hl=id">Google Scholar</a>, <a href="">PKP Indexing</a>, <a href=";refid=dclink">BASE (Bielefeld Academic Search Engine)</a>,&nbsp;<a href="">CiteFactor (Academic Scientific Journal)</a>, <a href="">CiteFactor (Academic Scientific Journals)</a> and <a href="">Directory of Research Journal Indexing (DRJI)</a>.&nbsp;</span></span><span class="" lang="en"><span class=""><span id="result_box" class="" lang="en">JoCAI strives to be a means of periodic, accredited, national scientific publications or reputable international publications through printed and online publications.<br></span></span></span><span class="" lang="en"><span class="">ISSN (Print) &nbsp;&nbsp;&nbsp; : 2580-6769<br></span></span><span class="" lang="en"><span class="">ISSN (Online)&nbsp;&nbsp;&nbsp;&nbsp; : 2580-829X</span></span><br>This work is licensed under a <a href="" rel="license">Creative Commons Attribution-NoDerivatives 4.0 International License</a>.</p> en-US <p>The Authors submitting a manuscript do so on the understanding that if accepted for publication, copyright of the article shall be assigned to&nbsp;<span id="result_box" class="" lang="en"><span class="">Journal of Informatics Technology and Computer Science, Universitas Sumatera Utara</span></span> as publisher of the journal.</p> <p>Copyright encompasses exclusive rights to reproduce and deliver the article in all form and media. The reproduction of any part of this journal, its storage in databases and its transmission by any form or media, will be allowed only with a written permission from <span id="result_box" class="" lang="en"><span class="">Journal of Informatics Technology and Computer Science</span></span>.</p> (Dr. Erna Budhiarti Nababan, M.I.T.) (Ainul Hizriadi) Wed, 30 Jan 2019 07:26:35 +0700 OJS 60 Geographical Considerations for Implementing Autonomous Unmanned Solar-HAPS for Communications Area Coverage <p>The impact and requirements for implementing stratospheric or high altitude vehicles for communications coverage may vary from one geographical location to another. These variations may impose significant constraints on energy and various key parameters of the vehicle’s operation and performance.This paper therefore, examines the potential for autonomous fixed-wing unmanned solar-powered High Altitude Platform Station or Pseudo-Satellite (HAPS) to provide persistent communications coverage. As a solar dependent platform, the potential for harnessing green energy and long platform endurance makes it an attractive communications coverage option. However, the variation of latitude and seasons across the globe presents an implementation constraint and challenges power availability and coverage capability. This paper investigates how the services of a typical solar-powered HAPS are affected by latitude and season. It shows that the degree of insolation directly affects the unmanned aircraft’s altitude, hence, its footprint diameter and power available to the communications payload. The paper highlights effective energy management algorithms as key to successful implementation of solar-powered unmanned HAPS especially at challenging latitudes and seasons</p> Ogbonnaya Anicho, Philip B Charlesworth, Gurvinder Baicher, Atulya Nagar Copyright (c) 2019 Data Science: Journal of Computing and Applied Informatics Mon, 28 Jan 2019 15:09:35 +0700 On Mathematical Braids <p><em>A braid is any sequence of crossings of the </em><em>-strand braid with a positive number n, provided none of the strands are self-crossing. The idea is that braids can be organized into groups, in which the group operation is *, which means: “do the first braid on a set of strands, and then follow it with a second on the twisted strand”. This study dealt with the formulation of additional basic properties of mathematical braids and the connection of mathematical braids to exponential theorems. Moreover, the researchers developed a program that could generate the total number of crossings and the total number of generators in an n-strand braid with a positive number n. </em></p> Milagros Baldemor Copyright (c) 2019 Data Science: Journal of Computing and Applied Informatics Tue, 29 Jan 2019 00:00:00 +0700 Premagic and Ideal Flow Matrices <p>Several interesting properties of a special type of matrix that has a row sum equal to the column sum are shown with the proofs. Premagic matrix can be applied to strongly connected directed network graph due to its nodes conservation flow. Relationships between Markov Chain, ideal flow and random walk on directed graph are also discussed.</p> Kardi Teknomo Copyright (c) 2019 Data Science: Journal of Computing and Applied Informatics Tue, 29 Jan 2019 00:00:00 +0700 Analyzing Decision Support System for Determining Eligibility of Home Ownership Loan Using Fuzzy Mamdani Logical Method and Technology Acceptance Model in Banking <p>Every year, the number of people who want to own a house by credit increase, therefore the chances of increasing problem loans will be greater. Non-Performing Loan (NPL) is an indicator to assess the performance of bank functions. The higher the NPL value, the performance of the bank is considered worse. In order to maintain the caution of banks (creditors) in the provision of credit, the bank needs to assess and determine the criteria of debtors who can be given credit. So the bank can make decisions precisely and accurately. In this research, the Researcher will design decision support system with Mamdani fuzzy logic method with the resulted output in the form of "rejected" or "approved" decision. The accuracy rate in this study is 98%. 2% of the difference consists of 63.64% is a debtor with NPL credit status (problematic). After the system was designed in this study, the researcher conducted an analysis to see the user behavior when using the system. The method used is Technology Acceptance Model (TAM). The result of TAM analysis is the simultaneous relationship among of all variables on the acceptance of information technology (acceptance of IT) have a positive impact. However, a partial relationship between perceived usefulness and attitude toward using does not have a positive effect.</p> Wendi Usino, Ayi Bayyinah Copyright (c) 2019 Data Science: Journal of Computing and Applied Informatics Tue, 29 Jan 2019 00:00:00 +0700 The Implementation Of Bellman-Ford Algorithm In Rembang Tourism Mobile Application As A Tourism Information Media <p>Tourism is one of the methods to publish the beauty of nature or the uniqueness of culture in a region that spreads from the coast up to the mountains. The distribution and the access to tourist attractions require mobile application. In creating the application, Bellman – Ford algorithm was used to get the shortest route. The algorithm was the Bellman – Ford algorithm which was used to calculate the shortest distance to the tourist attraction on the weighted graph. Testing the functionality of the application used a black box. The results showed that functions on the mobile application could run well. The compatibility testing showed 100% compatibility with a number of Android devices. In addition, the usability testing showed that the application was appropriate to use with percentage by 82.7% of the 30 respondents. The "Rembang tourism" mobile application can be used by users of information about tourism.</p> Eko Supraptono, Arief Arfriandi, Sulus Ilhamti Rizqian Copyright (c) 2019 Data Science: Journal of Computing and Applied Informatics Tue, 29 Jan 2019 00:00:00 +0700