Roberto A. Guerrero

Experiencing minix as a didactical aid for operating systems courses

Minix is a Unix clone Operating Systems to be run on IBM PCs and compatibles, designed by Tanembaum [10] for courses in the area.Accepting the Tanembaums proposal, this document describes the results of some extensions on the internal work of Minix as an exercise on Operating Systems Design and Implementation that attempts to transfer that experience to other groups of interest.The paper intends to be interpreted as a report remarking what kind of work was done having at our disposal an extensively documented copy of the source code of an operating system, taking into account that the developers are undergraduates in Computer Science.Further details on implementations will be available in future publications [1], [4], [6].

Implementation and evaluation of alternative process schedulers in MINIX

Minix is a Unix clone Operating System, designed by Tanembaum ([2],[3]) to allow beginners to do practical training in Operating Systems area.In this context the present paper describes the work done by a group of students implementing alternative process schedulers disciplines and their evaluation comparing performance estimates.Some unexpected deviations in the original implementation (Minix V. 1.0), found during software development, are also reported.

Be Civic: An Immersive Serious Game

Nowadays, serious games are one of the biggest existing industries and it is still growing steadily in many sectors. Particularly, the use of virtual worlds and serious games in education is growing. This paper introduces the development of a serious game in an immersive learning environment for teaching Civics. The work’s idea is to develop a game to motivate, educate and train learners on civic rules by placing users in different civic roles and giving them agency to address real-world problems and issues. In order to improve the user’s experience, the game was developed to work in a cave-like immersive environment by using a conversational character for a new kind of Human-Computer Interface. The game includes static and dynamic 3D environments, allowing players to share the experience of navigation in the scene among the users, even geographically distributed. In order to evaluate the game’s performance, a between groups experiment with thirty participants was designed. Received on 10 November 2016; accepted on 13 July 2017; published on 5 January 2018

Natural User Interfaces: A Physical Activity Trainer

Despite the known health benefits of regular participation in physical activity people still refuse this practise. Nowadays, Virtual Reality (VR) is a very powerful and compelling computer tool by which humans can interface and interact with computer-generated environments. In this paper, we propose a virtual training system which can be customized for the physical activity level of the user. System provides real time visual action guide and a performance’s feedback of users through a Natural User Interface (NUI). We conduct a brief pilot study to evaluate our virtual trainers in which participants’ performance doing physical activities is evaluated via our NUI. Initial results indicate that virtual training through a NUI is motivating and entertaining for any kind of user, in particular for individuals with low level of physical activity.

Management of interruptions to fractionated radiotherapy treatments: Four and a half years of experience

BACKGROUND AND PURPOSE The study objective was to report our four-and-a half years experience (March 1 2011-August 15 2015) of a program to manage interruptions in fractionated radiotherapy treatments. METHODS A program was developed, based on a specific database, to manage treatment interruptions. Benefits of the program were analyzed in reference to previously published data. Analysis was also performed of two measures to reduce OTT prolongation and improve treatment outcomes: working on public holidays and conducting treatment unit maintenance on Saturdays. RESULTS The study included 2352 patients. Patients with head and neck cancer obtained the greatest benefit from the program, with a mean increase in TCP of 3.5% and a benefit of at least 4% in 45.6% of them. In prostate cancer patients, the likelihood of biochemical failure was reduced by a mean of 2.0% and was reduced by at least 4% in 19.7% of them. Application of the two proposed measures would have improved the TCP by a mean of 5.4% in head and neck cancer patients. The impact of the compensations program and proposed measures is lesser in the remaining cancer types studied. CONCLUSIONS Implementation of a compensation program has a significant impact on patients with head and neck or prostate cancer but OTT prolongation remains excessive in many treatments. The introduction of fractions on public holidays would assist in the meeting of recommendations for these patients.

Sgraffito simulation through image processing

This paper presents a tool for simulating the traditional Sgraffito technique through digital image processing. The tool is based on a digital image pile and a set of attributes recovered from the image at the bottom of the pile using the Streit and Buchanan multiresolution image pyramid. This technique tries to preserve the principles of artistic composition by means of the attributes of color, luminance and shape recovered from the foundation image. A couple of simulated scratching objects will establish how the recovered attributes have to be painted. Different attributes can be painted by using different scratching primitives. The resulting image will be a colorimetric composition reached from the image on the top of the pile, the color of the images revealed by scratching and the inner characteristics of each scratching primitive. The technique combines elements of image processing, art and computer graphics allowing users to make their own free compositions and providing a means for the development of visual communication skills within the user-observer relationship. The technique enables the application of the given concepts in non artistic fields with specific subject tools.