Low-cost PC Research Articles

Controller Effect in Online Laboratories—An Overview

Online laboratories have been widely used in education, research, and industrial applications. For online laboratories, various architectures have been constructed to provide good user experience and powerful capabilities for online experimentation, in which the controller is a crucial part to connect the server with a controlled test rig. Regarding the physical nature of the controllers and test rigs used in online laboratories, a specific control process can be called a simulation, hardware-in-the-loop, rapid control prototyping, or physical control. This paper presents an overview of the most commonly used controllers in current online laboratories, focusing on the functionalities, use purposes, and types of different controllers, as well as their role in online laboratories for teaching and learning. In particular, the low-cost PC controller used in the Networked Control System Laboratory, which provides both remote and virtual experiments, is introduced. The limitations and potential development directions of online laboratories are identified.

Speech Assistant System With Local Client and Server Devices to Guarantee Data Privacy

Users of speech assistant systems have reservations about the distributed approach of these systems. They have concerns that people might get access to the transmitted speech data or that somebody is able to access their microphone from outside. Therefore, we investigate the concept of a setup with local client and server systems. This comes along with the requirement of cost-efficient realizations of client and server. We examined a number of different cost-efficient server solutions depending on the required recognition capability of specific applications. A fairly cost-efficient solution is the use of a small computing device for recognizing a few dozens of words with a GMM-HMM based recognition. To perform a DNN-HMM based recognition, we looked at small computing devices with an integrated additional graphical processor unit (GPU). Furthermore, we investigated the use of low-cost PCs for implementing real-time versions of the Kaldi framework to allow the recognition of large vocabularies. We investigated the control of a smart home by speech as an exemplary application. For this, we designed compact client systems that can be integrated at certain places inside a room, e.g., in a standard outlet socket. Besides activating a client by a sensor that detects approaching people, the recognition of a spoken wake-up word is the usual way for activation. We developed a keyword recognition algorithm that can be implemented in the client despite its limited computing resources. The control of the whole dialogue has been integrated in our client, so that no further server is needed. In a separate study, we examined the approach of an extremely energy-efficient realization of the client system without the need of an external power supply. The approach is based on using a special microphone with an additional low-power operating mode detecting the exceeding of a preset sound level threshold only. This detection can be used to wake up the client's microcontroller and to make the microphone switch to normal operating mode. In the listening mode, the energy consumption of the microphone is so low that a client system can be active for months with an energy supply from standard batteries only.

Development of Low Cost Miniature USB Based Data Acquisition System for Biomedical Instrumentation

In biomedical instrumentation, computer based data acquisition system is required for recording of physiological parameters and bioelectric signals, which allows signal processing, display, analysis and storage in digital media. However, Most of the commercially available PC based Data Acquisition systems are of very high cost and requires specific commercial software, again at a very high cost. Moreover, if the data is not stored in raw binary or known format, it is not possible for the user to use the data in other system or software of their own choice. Therefore, a low cost, simple and open source PC based data acquisition system for biomedical application would be very useful for biomedical instrument developers and researchers in the low resource countries. In this work, we present such development of data acquisition system. The developed system utilizes an 8-bit ordinary low cost microcontroller and some electronic circuit component to develop the data acquisition system and implementation of USB 1.1 (Universal Serial Bus) interface to PC. The onboard 10-bit ADC of the microcontroller was used for analog data sampling. Two sampling and data transfer mode is implemented, (i) Continuous mode with low sampling rate (800 sample/sec) and practically real time plotting and (ii) Batch mode, with high sampling rate (76.9 k sample/sec) but with batch type plotting. To evaluate the system, PC side GUI (Graphical User Interface) software was also developed. The GUI of system shows that a test sinusoidal signal is reproduced very nicely without any amplitude and phase distortion within the frequency band of 1 to 10 KHz. The system is suitable for low frequency bioelectric signals like ECG, EEG etc. and as well as high frequency signal like EMG, NCV etc. The system is low cost, miniature, simple, and efficient and being used in several indigenously developed medical devices like ECG, EMG, NCV and FIM [Rabbani et al, 1999] at the authors’ department with excellent satisfactory results.Bangladesh Journal of Medical Physics Vol.10 No.1 2017 1-11

Enif-Lang: A Specialized Language for Programming Network Functions on Commodity Hardware

The maturity level reached by today’s commodity platforms makes even low-cost PCs viable alternatives to dedicated hardware to implement real network functions without sacrificing performance. Indeed, the availability of multi-core processing packages and multi-queue network interfaces that can be managed by accelerated I/O frameworks, provides off-the-shelf servers with the necessary power capability for running a broad variety of network applications with near hardware-class performance. At the same time, the introduction of the Software Defined Networks (SDN) and the Network Functions Virtualization (NFV) paradigms call for new programming abstractions and tools to allow this new class of network devices to be flexibly configured and functionally repurposed from the network control plane. The paper presents the ongoing work towards Enif-Lang (Enhanced Network processIng Functional Language), a functional language for programming network functions over generic middleboxes running the Linux operating system. The language addresses concurrent programming by design and is targeted at developing simple stand-alone applications as well as pre-processing stages of packet elaborations. Enif-Lang is implemented as a Domain Specific Language embedded in the Haskell language and inherits the main principles of its ancestor, including the strong typedness and the concept of function compositions. Complex network functions are implemented by composing a set of elementary operations (primitives) by means of a compact yet expressive language grammar. Throughout the paper, the description of the design principles and features of Enif-Lang are accompanied by examples and use cases. In addition, a preliminary performance assessment is carried out to prove the effectiveness of the language for developing practical applications with the performance level required by 5G systems and the Tactile Internet.

Performance Analysis of Multi-GPU Implementations of Krylov-Subspace Methods Applied to FEA of Electromagnetic Phenomena

We present a comparison of performances of various graphic processing unit (GPU)-CUDA implementations of preconditioned Krylov-subspace methods, showing the impact of using a multi-GPU configuration. We aim to show that this resource allows the massively parallelized solution of large-scale real-world problems in state-of-the-art desktop PCs, since it overcomes the low-memory capacity of a single GPU, while still providing significant speedups when compared with either the usual sequential execution on a single-core CPU or an OpenMP implementation with four cores. The methods were selected based on their suitability to solve large-scale systems of equations arising from the 3-D finite-element analysis of open-bound earth current diffusion problems, both in steady state and under time-harmonic loading. In the latter, an ungauged harmonic edge-element formulation using the magnetic vector potential and the electric scalar potential was used. As the preconditioners suitable to this case, based on incomplete factorizations, are not appropriate for parallelization, we propose a hybrid CPU-GPU scheme to solve such problems, which still exhibits a competitive performance in low-cost PC desktops.

The Design of Intelligent Watt-Hour Meter Based STM32 System

In view of limitations function, cost and application in domestic meter at present, this paper was designed the low power consumption, low cost smart meters and PC system based on microprocessor MSP430F4794. It supports multi rate, step rate and power factor influence factor of electricity metering method, and can realize the real-time clock, timing backup data, monitoring the temperature and humidity of the environment and other functions, has the ability to forecast the next period of time energy consumption and carbon dioxide emissions of electrical appliances. Combined with the PC software, the backup data of smart meters to report, detailed list, and the data curve method is presented to the user, and facilitate to analysis of user. The whole embedded in smart meters and the host computer system provides a good human-computer interface, can realize the user personalized service configuration and software calibration function.

GPU Accelerated Generation of Digitally Reconstructed Radiographs for 2-D/3-D Image Registration

Recent advances in programming languages for graphics processing units (GPUs) provide developers with a convenient way of implementing applications which can be executed on the CPU and GPU interchangeably. GPUs are becoming relatively cheap, powerful, and widely available hardware components, which can be used to perform intensive calculations. The last decade of hardware performance developments shows that GPU-based computation is progressing significantly faster than CPU-based computation, particularly if one considers the execution of highly parallelisable algorithms. Future predictions illustrate that this trend is likely to continue. In this paper, we introduce a way of accelerating 2-D/3-D image registration by developing a hybrid system which executes on the CPU and utilizes the GPU for parallelizing the generation of digitally reconstructed radiographs (DRRs). Based on the advancements of the GPU over the CPU, it is timely to exploit the benefits of many-core GPU technology by developing algorithms for DRR generation. Although some previous work has investigated the rendering of DRRs using the GPU, this paper investigates approximations which reduce the computational overhead while still maintaining a quality consistent with that needed for 2-D/3-D registration with sufficient accuracy to be clinically acceptable in certain applications of radiation oncology. Furthermore, by comparing implementations of 2-D/3-D registration on the CPU and GPU, we investigate current performance and propose an optimal framework for PC implementations addressing the rigid registration problem. Using this framework, we are able to render DRR images from a 256×256×133 CT volume in ~24 ms using an NVidia GeForce 8800 GTX and in ~2 ms using NVidia GeForce GTX 580. In addition to applications requiring fast automatic patient setup, these levels of performance suggest image-guided radiation therapy at video frame rates is technically feasible using relatively low cost PC architecture.

A Synchronized Multipoint Vision-Based System for Displacement Measurement of Civil Infrastructures

This study presents an advanced multipoint vision-based system for dynamic displacement measurement of civil infrastructures. The proposed system consists of commercial camcorders, frame grabbers, low-cost PCs, and a wireless LAN access point. The images of target panels attached to a structure are captured by camcorders and streamed into the PC via frame grabbers. Then the displacements of targets are calculated using image processing techniques with premeasured calibration parameters. This system can simultaneously support two camcorders at the subsystem level for dynamic real-time displacement measurement. The data of each subsystem including system time are wirelessly transferred from the subsystem PCs to master PC and vice versa. Furthermore, synchronization process is implemented to ensure the time synchronization between the master PC and subsystem PCs. Several shaking table tests were conducted to verify the effectiveness of the proposed system, and the results showed very good agreement with those from a conventional sensor with an error of less than 2%.

A Platform for Real-Time Control Education with LEGO MINDSTORMS®

A set of software development tools for building real-time control systems on a simple robotics platform is described in the paper. The tools are being used in a real-time systems course as a basis for student projects. The development platform is a low-cost PC running GNU/Linux, and the target system is LEGO MINDSTORMS NXT, thus keeping the cost of the laboratory low. Real-time control software is developed using a mixed paradigm. Functional code for control algorithms is automatically generated in C from Simulink models. This code is then integrated into a concurrent, real-time software architecture based on a set of components written in Ada. This approach enables the students to take advantage of the high-level, model-oriented features that Simulink offers for designing control algorithms, and the comprehensive support for concurrency and real-time constructs provided by Ada.

PC-Cluster Based Storage System Architecture for Cloud Storage

Design and architecture of cloud storage system plays a vital role in cloud computing infrastructure in order to improve the storage capacity as well as cost effectiveness. Usually cloud storage system provides users to efficient storage space with elasticity feature. One of the challenges of cloud storage system is difficult to balance the providing huge elastic capacity of storage and investment of expensive cost for it. In order to solve this issue in the cloud storage infrastructure, low cost PC cluster based storage server is configured to be activated for large amount of data to provide cloud users. Moreover, one of the contributions of this system is proposed an analytical model using M/M/1 queuing network model, which is modelled on intended architecture to provide better response time, utilization of storage as well as pending time when the system is running. According to the analytical result on experimental testing, the storage can be utilized more than 90% of storage space. In this paper, two parts have been described such as (i) design and architecture of PC cluster based cloud storage system. On this system, related to cloud applications, services configurations are explained in detailed. (ii) Analytical model has been enhanced to be increased the storage utilization on the target architecture.

Development of a Motion Platform for an Educational Flight Simulator

Flight simulators are regularly used in the undergraduate and postgraduate training of mechanical and aeronautical engineers. Due to advances in computing technology, several flight simulation-related tasks can now be accomplished in real-time using low-cost PC platforms and inexpensive commercial software. The difficulty in realising an educational flight simulator system with motion platform therefore lies with the design and construction of an effective motion platform. Costs become exorbitant when simulation platforms of more than two degrees of freedom (i.e. pitch and roll) are attempted. This paper describes the development of a drive system for a motion platform with two degrees of freedom (pitch and roll) for use in undergraduate engineering training. Use was made of off-the-shelf PC equipment and flight simulation software and hardware, together with commercial actuators and drive systems. The motion platform was manufactured from square tubing and consisted of three frames: the stationary main frame and, rotating inside this, the roll frame and pitch frame. These rotated relative to each other and were actuated by two similar-sized DC motors and gearbox/chain transmissions. The system effectively simulated the pitch and roll motions of commercial airliners, using a low-cost, easily maintainable motion platform. The educational value of the simulator was twofold: first, it was to be displayed in the science exploratorium (SciEnza) of the University of Pretoria; and second, it provided a platform on which mechanical (as well as electrical, electronic and computer) engineering students could conduct practical work in courses such as dynamics and control, and on which final-year and postgraduate students could conduct research.

GPU Accelerated 2-D Staggered-grid Finite Difference Seismic Modelling

The staggered-grid finite difference (FD) method demands significantly computational capability and is inefficient for seismic wave modelling in 2-D viscoelastic media on a single PC. To improve computation speedup, a graphic processing units (GPUs) accelerated method was proposed, for modern GPUs have now become ubiquitous in desktop computers and offer an excellent cost-to-performance-ratio parallelism. The geophysical model is decomposed into subdomains for PML absorbing conditions. The vertex and fragment processing are fully used to solve FD schemes in parallel and the latest updated frames are swapped in Framebuffer Object (FBO) attachments as inputs for the next simulation step. The seismic simulation program running on modern PCs provides significant speedup over a CPU implementation, which makes it possible to simulate realtime complex seismic propagation in high resolution of 2048*2048 gridsizes on low-cost PCs.

Comparative study of netbooks and tablet PCs for fostering face-to-face collaborative learning

With the recent appearance of netbooks and low-cost tablet PCs, a study was undertaken to explore their potential in the classroom and determine which of the two device types is more suitable in this setting. A collaborative learning activity based on these devices was implemented in 5 sessions of a graduate engineering course of 20 students, most of whom were aged 22–25 and enrolled in undergraduate computer science and information technology engineering programs. Student behavior attributes indicating oral and gesture-based communication were observed and evaluated. Our findings indicate that in the context in which this study was undertaken, tablet PCs strengthen collective discourse capabilities and facilitate a richer and more natural body language. The students preferred tablet PCs to netbooks and also indicated greater self-confidence in expressing their ideas with the tablet’s digital ink and paper technology than with the netbooks’ traditional vertical screen and keyboard arrangement.

An Evolutionary Genetic Algorithm for Optimization of Distributed Database Queries

High-performance low-cost PC hardware and high-speed LAN/WAN technologies make distributed database (DDB) systems an attractive research area where query optimization and DDB design are the two important and related problems. Since dynamic programming is not feasible for optimizing queries in a DDB, we propose a new genetic algorithm (GA)-based query optimizer (new genetic algorithm (NGA)) and compare its performance with random and optimal (exhaustive) algorithms. We perform experiments on a synthetic database with replicated relations, but no horizontal or vertical fragmentation. Network links are assumed to be gigabit ethernet. Comparisons with optimal results show that our NGA formulation performs only 20% of the optimal results and we have achieved 50% improvement over a previous GA-based algorithm.

A scalable parallel Poisson solver for three-dimensional problems with one periodic direction

A code for the direct numerical simulation (DNS) of incompressible flows with one periodic direction has been developed. It provides a fairly good performance on both Beowulf clusters and supercomputers. Since the code is fully explicit, from a parallel point-of-view, the main bottleneck is the Poisson equation. To solve it, a Fourier diagonalization is applied in the periodic direction to decompose the original 3D system into a set of mutually independent 2D systems. Then, different strategies can be used to solved them. In the previous version of the code, that was conceived for low-cost PC clusters with poor network performance, a Direct Schur-complement Decomposition (DSD) algorithm was used to solve them. Such a method, that is very efficient for PC clusters, cannot be used with an arbitrarily large number of processors and mesh sizes, mainly due to the RAM memory requirements. To do so, a new version of the solver is presented in this paper. It is based on the DSD algorithm that is used as a preconditioner for a Conjugate Gradient method. Numerical experiments showing the scalability and the flexibility of the method on both the MareNostrum supercomputer and a PC cluster with a conventional 100 Mbits/s network are presented and discussed. Finally, illustrative DNS results of an air-filled differentially heated cavity at Ra = 10 11 are also presented.

Digital Games Distribution: The Presence of the Past and the Future of Obsolescence

Digital Games Distribution: The Presence of the Past and the Future of Obsolescence

Little mass appeal for intel's mobile internet device

The mobile-computing-device market is a little like the car market. On the high end, you've got your big, fully loaded luxury models- that would be your large-screen laptops. On the low end, you've got your park-anywhere, use- minimal- power gizmos-your smartphones. In between, you've got a range of sedans and lowcost compacts-your tablet PCs, subnotebooks, and netbooks.

Web móvil y bibliotecas

Mobility and access to Web contents and services from any place having an internet connection are both advantages of using mobile devices like mobile phones, pdas, smartphones, ultra mobile PCs or ultra low cost PCs. However, new questions also arise, mainly related to content accessibility: their characteristics, connections and the way people in motion connect to the internet generate different requirements. In this paper a general landscape of the mobile web is drawn from a librarian’s perspective

P2P and MPEG FGS Encoding: A Good Recipe for Multipoint Video Transmission on the Internet

In the last years Peer-to-Peer (P2P) systems have gained ground for content sharing between communities, determining a real revolution on the Internet. The characteristics of P2P systems make them a very good choice for multimedia content distribution over IP networks. However, although P2P technology gives new opportunities to define an efficient multimedia streaming application, at the same time it involves a set of technical challenges and issues due to the best-effort service offered by the Internet and its dynamic and heterogeneous nature. The most of existent protocols for video communications over P2P mainly focus on tree topology maintenance, without paying any attention to the encoding problem. The idea of this paper is to propose a multipoint video broadcast framework over a heterogeneous content distribution P2P network. In the proposed system the source generates the video flow by using an MPEG-4/FGS encoder, in such a way that no losses occur at the Baselayer stream even in the presence of short-term bandwidth fluctuations. Although in the past the FGS was not employed due to its encoding complexity, today, thanks to advances in hardware technology, we were able to develop an MPEG-4/FGS encoder on low-cost PCs which turned out to be more feasible and appealing for its flexibility. The FGS layer is sent together with the Base layer, but with a lower priority. The source uses a rate controller to regulate the encoding rate of the Base layer. To this aim, a protocol is defined in order to provide the source with information related to the most stringent bottleneck link on the overlay network. A technique to reorganize the content distribution tree is proposed and discussed. To evaluate the performance of the proposed framework a case study is introduced; improvements obtained with respect to several reference cases where FGS is not applied are also shown.

A distributed modelling framework for large-scale microscopic traffic simulation

Simulation modelling is an increasingly popular and effective tool for analysing transportation problems, which are not amendable to study by other means. In this paper, we examine the need for distributed simulation from the perspective of computational speedup and development of large-scale network simulation contexts and datasets. After an overview of the general techniques for the distributed discrete-event simulation and previous efforts on the distributed traffic simulation, we present the general architecture of the proposed distributed modelling framework. Two categories of modelling strategies, namely, light global control/independent subnets versus heavy global control/coordinated subnets are described. We have implemented the distributed scheme of light global control/independent subnets and the implemented details, such as communication techniques and vehicle transferring across the boundary of two subnets are discussed. Unlike the previous studies using the dedicated high performance machines, our efforts are to utilise the low-cost networked PCs that are commonly available. By using the Application Programming Interface (API) functions supported by off-the-shelf microscopic traffic simulation software Paramics, we are able to distribute the computational load of microscopic simulation to multiple single-processor PCs without access the proprietary source codes of the simulation program. Performance testing and analysis of the implemented prototype demonstrate that the proposed framework is very promising.