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Synthetic aperture radar (SAR) imaging is the most computational intensive algorithm and this makes its implementation challenging for real-time application. This paper aims to present the chirp-scaling algorithm (CSA) for real-time SAR applications, using advanced field programmable gate array (FPGA) processor.

A chirp signal is generated and compressed using range Doppler algorithm in MATAB for validation. Fast Fourier transform (FFT) and multiplication operations with complex data types are the major units requiring heavy computation. Therefore, hardware acceleration is proposed and implemented on NEON-FPGA processor using NE10 and CEPHES library.

The heuristic analysis of the algorithm using timing analysis and resource usage is presented. It has been observed that FFT execution time is reduced by 61% by boosting the performance of the algorithm and speed of multiplication operation has been doubled because of the optimization.

Very few literatures have presented the FPGA-based SAR imaging implementation, where analysis of windowing technique was a major interest. This is a unique approach to implement the SAR CSA using a hybrid approach of hardware–software integration on Zynq FPGA. The timing analysis propagates that it is suitable to use this model for real-time SAR applications.

This paper surveys theoretical and practical issues associated with a particular type of information retrieval problem, namely that where the information need is pictorial. The paper is contextualised by the notion of a visually stimulated society, in which the ease of record creation and transmission in the visual medium is contrasted with the difficulty of gaining effective subject access to the world's stores of such records. The technological developments which, in casting the visual image in electronic form, have contributed so significantly to its availability are reviewed briefly, as a prelude to the main thrust of the paper. Concentrating on still and moving pictorial forms of the visual image, the paper dwells on issues related to the subject indexing of pictorial material and discusses four models of pictorial information retrieval corresponding with permutations of the verbal and visual modes for the representation of picture content and of information need.

Internet has changed radically in the way people interact in the virtual world, in their careers or social relationships. IoT technology has added a new vision to this process by enabling connections between smart objects and humans, and also between smart objects themselves, which leads to anything, anytime, anywhere, and any media communications. IoT allows objects to physically see, hear, think, and perform tasks by making them talk to each other, share information and coordinate decisions. To enable the vision of IoT, it utilizes technologies such as ubiquitous computing, context awareness, RFID, WSN, embedded devices, CPS, communication technologies, and internet protocols. IoT is considered to be the future internet, which is significantly different from the Internet we use today. The purpose of this paper is to provide up-to-date literature on trends of IoT research which is driven by the need for convergence of several interdisciplinary technologies and new applications.

A comprehensive IoT literature review has been performed in this paper as a survey. The survey starts by providing an overview of IoT concepts, visions and evolutions. IoT architectures are also explored. Then, the most important components of IoT are discussed including a thorough discussion of IoT operating systems such as Tiny OS, Contiki OS, FreeRTOS, and RIOT. A review of IoT applications is also presented in this paper and finally, IoT challenges that can be recently encountered by researchers are introduced.

Studies of IoT literature and projects show the disproportionate importance of technology in IoT projects, which are often driven by technological interventions rather than innovation in the business model. There are a number of serious concerns about the dangers of IoT growth, particularly in the areas of privacy and security; hence, industry and government began addressing these concerns. At the end, what makes IoT exciting is that we do not yet know the exact use cases which would have the ability to significantly influence our lives.

This survey provides a comprehensive literature review on IoT techniques, operating systems and trends.

The simple environment for context aware systems (SECAS) Project deals with the adaptation of applications to the context (user preferences and environment, terminal, etc.). The authors aim to develop a platform which makes the services, data and the user interface of applications adaptable to different context situations.

Previous research has concentrated on how to capture context data and how to carry it to the application. The present work focuses on the impact of context on the application core. A case study in the medical field is also analysed.

The paper illustrates a new definition of the context which separates the application data from the parameters of the context. This definition helps to establish a complete study on how to adapt applications on their three dimensions (services, content and presentation) to the context.

The paper presents the SECAS platform, one that ensures the deployment of adaptive context‐aware applications.

One of the most horrifying computer experiences a user can encounter is the destruction of files due to system malfunction or operator error. Even a relatively small computer file, containing only a few thousand bytes, may represent many hours of manual and intellectual labour. Larger files may form the foundation for the daily operations of an individual or of an entire library.

Advances in telecommunications are providing libraries with the ability to link networks, to move information at faster and faster speeds and to combine data in ways barely perceived 20 years ago. In Journey to the 21st Century, the summary of OCLC's Strategic Plan, OCLC's telecommunications strategy stated that between 1995 and 2000, OCLC would become fully integrated into the digital, global community that is emerging. This document summarizes OCLC's linking strategy with respect to US national networks that are becoming part of that global community — the Internet and its next phase, the National Research and Education Network (NREN).

The need for standards allowing computer‐to‐computer communication, and examples of technical issues are discussed. The framework of the Open Systems Interconnection Reference Model, consisting of seven layers, each performing a distinct and defined function, is explained and illustrated. Sidebars feature: 1) public data networks and X.25, 2) OSI standards, and 3) the OSI layer functions. A glossary is included.

If you think your 9600 bit per second (bps) modem is fast, you should be aware that modems operating at 14 400 bps are now available for under $150, and that vendors are beginning to offer modems that can operate at 28 800 bps.

The purpose of this paper is to study the flexural behavior of additively manufacture Ultem 1010 parts. Fused deposition modeling (FDM) process has become one of most widely used additive manufacturing methods. The process provides the capability of fabricating complicated shapes through the extrusion of plastics onto a print surface in a layer-by-layer structure to build three-dimensional parts. The flexural behavior of FDM parts are critical for the evaluation and optimization of both material and process.

This study focuses on the performance of FDM solid and sparse-build Ultem 1010 specimens. Flexure tests (three-point bend) are performed on solid-build coupons with varying build orientation and raster angle. These parameters are investigated through a full-factorial design of experiments (DOE) to determine optimal build parameters. Air gap, raster width and contour width are held constant. A three-dimensional nonlinear finite element model is built to simulate the flexural behavior of the FDM parts.

Experimental results include flexure properties such as yield strength and modulus, as well as analysis of the effect of change in build parameters on material properties. The sparse-build FDM parts chosen from the experimental tests are simulated based on this developed model. Thermo-mechanical simulation results show that the finite element simulation and experimental tests are in good agreement. The simulation can be further extended to other complicated FDM parts.

From the DOE study, sparse-build coupons with specific build parameters are fabricated and tested for the validation of a finite element simulation.

An introduction to disc‐based audio‐video technologies

Description of the basic disc‐based audio‐video technologies.

Provides the baseline for types of disc‐based audio‐video technology such as holographic video disc (HVD), BluRay, HD DVD, DVD‐Audio and others.

This paper is useful for information management professionals who seek greater understanding of the basics disc storage medium.