Operating systems (Computers)

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Teaching “Embedded Operating Systems” using Raspberry Pi and Virtual Machines

Teaching “Embedded Operating Systems” using Raspberry Pi and Virtual Machines

In this paper we will focus in the last one, Embedded Operating Systems. This subject assumes the existence of an embedded hardware capable of run- ning a tailored version of GNU/Linux. To do so, such a system should have at least a microprocessor with MMU management, 4 Mb of RAM and about 8 Mb of secondary storage, typically solid-state disks such as memory cards. Note that this was the standard configuration of a commodity PC in early 90s. However, miniaturization and cost reduction, together with the advent of low- powered Systems on Chip (SoC) have allowed the production of computers with these or better characteristics for less than forty euros. This is precisely the case of the Raspberry Pi microcomputer.
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8 Lee mas

Using portable monitoring for heterogeneous clusters on Windows and Linux operating systems

Using portable monitoring for heterogeneous clusters on Windows and Linux operating systems

The main contribution of this work is the multi- platform monitoring realized by XPVM-W95. XPVM-W95 is a new monitoring software tool for parallel platforms that uses PVM message passing environment. This tool was projected initially to be executed on the Windows 9x operating system, and using the PVM-W95. The actual XPVM-W95 source code was restructured, favoring the monitoring at different operating systems, such as Windows and Linux. The changes in the code source were realized in order to guarantee the portability as well as to reduce the intrusion caused by the tool. XPVM-W95 offers a friendly graphical interface for the PVM console, it allows parallel environment monitoring and it also offers support for workload analysis. The tool is flexible, portable and now it can be easily adapted for other platforms, based on the UNIX operating system.
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7 Lee mas

Learning Programming by applied activities: an example with topics of Operating Systems

Learning Programming by applied activities: an example with topics of Operating Systems

The relationship between these two subjects is clear, and due to this reason we consider that a practical programming project in the context of operating systems is a good proposal. not only to practice programming applied to a real problem [1] [2] [3], but also to introduce some concepts related to OS [5], [6], [7], [8], [9], [10], [11], [12].

10 Lee mas

Active learning and generic competences in an operating systems course

Active learning and generic competences in an operating systems course

OSI is divided into five topics: Introduction, Process and Threads, Memory Management, Input/Output and File Systems. Students only had one reference book [32] in order to meet the topics as well as two other additional reference books [33-34]. During the academic year 2007/08, the first two topics were taught using CL, while the rest used PBL. Courses were aimed at 1) ensuring that students could understand theoretical know- ledge; and 2) providing them with abilities to deal with new problems related to the modern basic concepts of operating systems (practice application and operative knowledge). The course developed along 15 weeks. A two-hour session was held weekly. Besides, during five of these weeks there was a two-hour practice session. Apart from these 40 hours of class work, students should invest over 80 additional hours of individual or group work so as to solve the problems raised by the professor and to study the material. Four activities were developed along the course: Lab exercises, CL, PBL and Test, which will be described below. Lab exercises. Students had to do five lab exercises related to the subject topics. They used several simulators [35] during lab sessions. These sessions were carried out implementing CL with a jigsaw technique. Each session lasted 110 minutes. The lab instructor divided students ad hoc into groups of four in every lab session. Students were assigned a group randomly. The number of groups varied from 5 to 7 depending on the session. The first lab session consisted in a training session, where the instructor showed students CL following a jigsaw technique by using a problem about POSIX (Por- table Operating System Interface) system calls. Simulators were used during the following four sessions. The manual of the simulator was divided into four parts and a different part was assigned to each member of the group. The proposed experi- ment could only be solved if all of the members worked together and shared with the rest the individual knowledge acquired about the simula- tor. The instructor gave each member 15 minutes to read the assigned part of the manual. Later, all the members joined the other students who had been assigned the same part of the manual. After- wards, they gathered again in groups of four people, which are called ‘expert groups’. Students met for 10 minutes in order to discuss and clear up doubts. Then, all the students returned to the initial configuration. For 5 minutes, each expert in a group taught the other members about the information learned. After 20 minutes time, the instructor gave the groups the problem to be solved. It had to be solved within 40 minutes. The solution of the problem needs information
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9 Lee mas

TítuloSelf tuning of disk input–output in operating systems

TítuloSelf tuning of disk input–output in operating systems

One of the most difficult and hard to learn tasks in computer system man- agement is tuning the kernel parameters in order to get the maximum perfor- mance. Traditionally, this tuning has been set using either fixed configura- tions or the subjective administrator’s criteria. The main bottleneck among the subsystems managed by the operating systems is disk Input/Output (I/O). An evolutionary module has been developed to perform the tuning of this subsystem automatically, using an adaptive and dynamic approach. Any computer change, both at the hardware level, and due to the nature of the workload itself, will make our module adapt automatically and in a transparent way. Thus, system administrators are released from this kind of task and able to achieve some optimal performances adapted to the frame- work of each of their systems. The experiment made shows a productivity increase in 88.2% of cases and an average improvement of 29.63% with regard to the default configuration of the Linux operating system. A decrease of the average latency was achieved in 77.5% of cases and the mean decrease in the request processing time of I/O was 12.79%.
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28 Lee mas

A Systematic Map for Improving Teaching and Learning in Undergraduate Operating Systems Courses

A Systematic Map for Improving Teaching and Learning in Undergraduate Operating Systems Courses

ABSTRACT Operating Systems (OS) is an important area of knowledge included in virtually all undergraduate computing curricula and in some engineering curricula as well. Teaching and learning an OS undergraduate course have always been a challenge. Several different approaches have been used for OS teaching and learning. Nevertheless, it is not easy for a teacher to choose one of them. No guidelines are available on how to choose one of them to match the specific objectives of each OS course. The objective of this paper is to analyze the approaches that have been used to improve OS teaching and learning by applying a systematic map. In particular, we consider the following dimensions: learning objectives, assessment, empirical study, methodology, and mode (face-to-face, online, or blended). The systematic map devised in this paper is focused on the time span from 1995 to 2017 and considered six of the major publications on the Computer Science Education. We considered three journals (the Journal of Engineering Education, the IEEE T RANSACTIONS ON E DUCATION , and the International Journal of Engineering Education) and three conferences (the ACM Technical Symposium on Computer Science Education—SIGCSE, the Conference on Computing Education Research—ITiCSE, and the International Conference on Computing Education Research—Koli). A total of 55 papers were included in the study after performing a search based on the inclusion/exclusion criteria. Nine approaches to improve OS teaching and learning were identified and analyzed. Furthermore, the implications for OS instructors and for research in this field are discussed.
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19 Lee mas

Operating systems data transfer optimization

Operating systems data transfer optimization

Today most data come from systems related to the World Wide Web or interconnected via the Internet. Inter-networked physical devices connected and communicating to each other will be around 30 billion objects by 2020 [HWANG, 2013]. Imagine the amount of raw data that such number of devices can generate and that will need to be processed by an endpoint device as fast as possible, so that a user does not have to wait. Depending on the medium, these data traverses the Internet, where most personal computers and smartphones connect to wireless access points utilizing a wireless network card. A card of this type is embedded in smartphones, access points, tablets, laptops, and personal computers. All these data are taken from the physical medium and processed by embedded software that receives the data and transforms it in such a way that the device ‘understands’ it and shows it in an easy way for a human brain to interpret. All this process involves a means to move data from {R} to {Z}.
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123 Lee mas

Framework for Integration of Heterogeneous Mobile Devices  Edición Única

Framework for Integration of Heterogeneous Mobile Devices Edición Única

Qt is a cross-platform application framework, which enables web and native application development. One of the main features of this framework is its support for desktop as well as mobile platforms. QT is not a runtime tool, therefore there are not performance constraints. QT Framework is developed in C++, and it provides libraries for each operating system. Building a QT application makes use of the platform specific pre-built QT libraries, making easy to integrate custom components. Applications can be written once and deployed across multiple operating systems, using the same source code.
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138 Lee mas

Design and implementation considerations for a pedagogical object oriented operating system . MTech Thesis, Jan 2009

Design and implementation considerations for a pedagogical object oriented operating system . MTech Thesis, Jan 2009

The operating system has a modular and stratified design with five distinct layers comprising of system components and application programs (Figure 1). The lowest layer consists of the microkernel and the clock driver. The second layer contains the drivers for common input/output devices including keyboard, display, mouse and printers. In contrast to most operating systems, these device drivers execute in an unprivileged user mode and can access the computer hardware only through the microkernel. The third layer contains system components for consolidation and optimization of services provided by the layers below it. These components include a teletype driver and a message type reader component. The fourth layer contains several servers each providing a particular type of service. These servers include the process manager, the information server, the file server, the login server, the reincarnation server and the verbose server. The fifth layer contains the shell, inbuilt utility programs and application programs. The programs in the fifth layer are free to make any number of system calls to any of the servers in the fourth layer. The servers, on their part, service these request and thus complete the client-server architecture.
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2 Lee mas

Complex fluctuations and robustness in stylized signalling networks

Complex fluctuations and robustness in stylized signalling networks

Abstract. Complex fluctuations with correlations involving multiple scales appear in many physical, social and biological systems. In particular, in physiological systems the degree of complexity, measured in terms of the exponent of the time correlations of the fluctuations, is altered with disease and ageing. Here, we show that correlated fluctuations characterized by 1/f scaling of their power spectra can emerge from networks of simple signalling units. We analyse networks of simple signalling units where the type of scaling of the fluctuations is associated with (i) a complex topology with a discrete and sparse number of random links between units, (ii) a restricted set of nonlinear interaction rules, and (iii) the presence of noise. Furthermore, we find that changes in one or more of these properties leads to degradation of the correlation properties. Moreover, changes in the microscopic construction of the model do not produce qualitative changes in the dynamical behaviour, showing hence the robustness of our findings.
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19 Lee mas

A toolset for the development of mixed-criticality partitioned systems

A toolset for the development of mixed-criticality partitioned systems

When the UML2 standard was approved [15], the OMG realized that it was necessary to define a profile for real-time and embedded systems. The new profile was called Modelling and Analysis of Real-Time and Embedded [16]. MARTE is a profile for providing support for modelling and analysing real-time and embedded systems. It includes several packages for describing non-functional properties, as well as some secondary profiles for di↵erent kinds of systems. It was designed to be compatible with already existing profiles for quality of service and fault tolerance that provide support for annotating embedded systems issues, such as energy consumption, memory, etc. Its main goals are:
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12 Lee mas

Does Familiarization with CALL  Improve Students' Attitudes towards CALL?

Does Familiarization with CALL Improve Students' Attitudes towards CALL?

of computers´ motivational power. So we could argue that familiarization with computers for language learning is one of the variables which influence students´attitudes towards CALL. On the other hand, we should not obviate the importance of the teacher´s presence in the CALL class, but not, as said before, “as part of the furniture of the classroom”, but as someone who moves around the class, addressing student needs and allowing students to address him/her.

7 Lee mas

Autonomous dynamical systems based on hardware implementations of delay reservoir computers

Autonomous dynamical systems based on hardware implementations of delay reservoir computers

In the previous chapter, we have introduced delay-based RC as a potential platform to implement RC experimentally. Here we introduce a practical implementation of the single node delayed feedback reservoir. In this case, the RC implementation is based on a single Mackey Glass (MG) nonlinear element with delay. Choosing a MG oscillator is motivated by the existence of a well-tested design using simple elec- tronic components. Another beneficial characteristic of this nonlinearity is its tun- ability, by changing components we can access optimal operating points depending on the desired task. The experimental setup was previously built and tested by M.C. Soriano. The author of this TFM has developed new numerical simulations and ex- periments based on previous publications [1, 36].
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42 Lee mas

A design framework for wireless sensor networks

A design framework for wireless sensor networks

As a supporting example, as well as prevailing paradigm, lots of experimental sensornets today run on top of TinyOS [10] and TinyDB [11]. The first, TinyOS, is an open-source operating system specially trimmed for sensornets. It features a component-based architecture which enables rapid prototyping and implementing sensornet applications via providing higher-level programming abstractions. The latter, TinyDB, is a query processing system for extracting information from sensornets made from sensors running TinyOS. It features a SQL-like query interface technology which alleviates the complex of writing low-level C codes and supports traditional database queries with auxiliary sensornet parameters.
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9 Lee mas

Implementation of algorithms for radar real-time signals processing using a microprocessor based platform

Implementation of algorithms for radar real-time signals processing using a microprocessor based platform

Research in the field of radar technology had had the disadvantage of high costs, implying a difficult access. Nowadays it is possible to obtain low-cost modules for development as the sensor used in this project. Additionally, radar technology trends indicate a growing preference for digital technology and real-time processing. Digital technology nowadays has extended the use of free platforms both hardware and software. These platforms besides having low cost, has a large community of users working and actively developing solutions. In this project these trends are used to develop a system for detecting the presence and radial velocity. Using a Doppler sensor and an open hardware platform using a real-time operating system to guarantee determinism in response times. The radar module used is the MDU1100T from the manufacturer Microwave Solutions. The hardware platform for digital processing used is the Raspberry Pi computer and for guarantee software real-time support, Xenomai over Raspbian is used.
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52 Lee mas

Multifunction IO Devices for PCI Bus Computers

Multifunction IO Devices for PCI Bus Computers

(2) IN ANY APPLICATION, INCLUDING THE ABOVE, RELIABILITY OF OPERATION OF THE SOFTWARE PRODUCTS CAN BE IMPAIRED BY ADVERSE FACTORS, INCLUDING BUT NOT LIMITED TO FLUCTUATIONS IN ELECTRICAL POWER SUPPLY, COMPUTER HARDWARE MALFUNCTIONS, COMPUTER OPERATING SYSTEM SOFTWARE FITNESS, FITNESS OF COMPILERS AND DEVELOPMENT SOFTWARE USED TO DEVELOP AN APPLICATION, INSTALLATION ERRORS, SOFTWARE AND HARDWARE COMPATIBILITY PROBLEMS, MALFUNCTIONS OR FAILURES OF ELECTRONIC MONITORING OR CONTROL DEVICES, TRANSIENT FAILURES OF ELECTRONIC SYSTEMS (HARDWARE AND/OR SOFTWARE), UNANTICIPATED USES OR MISUSES, OR ERRORS ON THE PART OF THE USER OR APPLICATIONS DESIGNER (ADVERSE FACTORS SUCH AS THESE ARE HEREAFTER COLLECTIVELY TERMED “SYSTEM FAILURES”). ANY APPLICATION WHERE A SYSTEM FAILURE WOULD CREATE A RISK OF HARM TO PROPERTY OR PERSONS (INCLUDING THE RISK OF BODILY INJURY AND DEATH) SHOULD NOT BE RELIANT SOLELY UPON ONE FORM OF ELECTRONIC SYSTEM DUE TO THE RISK OF SYSTEM FAILURE. TO AVOID DAMAGE, INJURY, OR DEATH, THE USER OR APPLICATION DESIGNER MUST TAKE REASONABLY PRUDENT STEPS TO PROTECT AGAINST SYSTEM FAILURES, INCLUDING BUT NOT LIMITED TO BACK-UP OR SHUT DOWN MECHANISMS. BECAUSE EACH END-USER SYSTEM IS CUSTOMIZED AND DIFFERS FROM NATIONAL INSTRUMENTS' TESTING PLATFORMS AND BECAUSE A USER OR APPLICATION DESIGNER MAY USE NATIONAL INSTRUMENTS PRODUCTS IN COMBINATION WITH OTHER PRODUCTS IN A MANNER NOT EVALUATED OR CONTEMPLATED BY NATIONAL
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118 Lee mas

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