Application-specific Components Research Articles

Advancement of extreme environment additively manufactured alloys for next generation space propulsion applications

The National Aeronautics and Space Administration (NASA) has been involved in the development and maturation of metal additive manufacturing (AM) for space applications since the late 2000's. Several efforts have focused on the understanding of AM processes through material characterization and testing, standards development, component fabrication, and infusion into propulsion development and flight applications. NASA matured commonly used aerospace alloys from various alloy families (Nickel, Copper, Stainless and Steel, Aluminum, and Titanium-based) through detailed AM process and heat treatment characterization, in addition to mechanical and thermophysical testing. While these alloys are actively used in many propulsion applications, there is a need for ongoing AM optimized alloys using integrated computational materials engineering (ICME) and process development for high performance applications. The applications targeted are liquid rocket engines; advanced propulsion systems; and in-space propulsion with high heat fluxes, high pressure, and/or that use propellants that can degrade alloys (e.g., hydrogen). This paper highlights the characterization and physical properties of the more common AM alloys using laser powder bed fusion (L-PBF) and laser powder directed energy deposition (LP-DED) processes. Additionally, this paper discusses some of the ongoing novel alloy development and maturation using AM for use in these harsh environments, such as GRCop-42, GRCop-84, NASA HR-1, GRX-810, and C-103. The results from these processes demonstrated that AM could enable rapid development, and that optimized alloys could be developed using ICME, yielding higher performances. These alloys have undergone modeling, fundamental metallurgical evaluations, heat treatment studies, detailed microstructure characterization, and mechanical testing campaigns. This, combined with direct application-specific component fabrication and hot-fire testing, enabled the increase of the Technology Readiness Level (TRL) through high duty-cycle testing. A background and overview of these novel AM-enabled alloys and AM processing developments including metallurgical and mechanical property studies is presented here. The latest advancement in the parallel component development and hot-fire testing and future developments for these alloys is also discussed.

TheiaNet: Towards fast and inexpensive CNN design choices for image dehazing

This work examines inexpensive design choices for dehazing as an end-to-end image-to-image mapping problem without relying on the physical scattering model. The proposed TheiaNet is free from intermediate-computation of transmission map, enabling haze removal in a highly resource constrained environments. The simplicity of the network is augmented by a spatial cleaning bottleneck block, that adds faster feature extraction without adding to trainable parameters. We also analyze the effectiveness of multi-cue color space (RGB, HSV, LAB, YCbCr) over single cue color space (RGB) for end-to-end dehazing. A comprehensive set of experiments were conducted on HazeRD, D-Hazy and the more recent Reside datasets. The proposed TheiaNet significantly outperforms the existing CNN and GAN based state-of-the-art methods in terms of PSNR and SSIM on all these datasets. It also outperforms all existing methods in term of speed, compute and memory efficiency, making it more efficient. This work highlights how judicious application-specific components can augment simple CNNs to denoise faster, and more accurately than deeper heavier networks, which is supported by an ablation analysis as well.

Energy efficient heuristic application mapping for 2-D mesh-based network-on-chip

Application mapping in 2-D mesh-based Network-on-Chip (NoC) architecture is an optimization problem in which each application task (e.g., processor or memory units) should be mapped one-to-one onto a network element (switch or router) to optimize performance requirements (e.g., communication energy or communication latency) under certain platform constraints (e.g., bandwidth and/or latency). Network-on-Chip is a scheme that establishes links between limited application-specific components within Multi-Processor System-on-Chip (MPSoC), but it has a vital role to ensure the maximum data transfer rate and reduce total number of physical interconnections. Most of the works on heuristic application mapping for mesh-based NoC design aim to minimize both total communication energy and run-time, however they experience the following issues: (i) relatively high CPU time due to linear search for the task and tile mapping combinations, (ii) consumption of relatively high communication energy due to random tile selection when two or more tiles are equivalent in terms of average weighted distance by their adjacent mapped tasks, and (iii) even after constructive application mapping, some of the tasks consume higher communication energy due to their inappropriate placements. In this paper we present a low time-complexity heuristic mapping algorithm of weighted application graph under permissible bandwidth constraint to minimize communication energy of 2-D mesh-based NoC architecture. The experimental results of multimedia benchmarks, as well as randomly generated samples show the low communication energy as well as time-complexity under bandwidth constraints in comparison to the recent heuristic application mapping approaches. In our approach, the communication energy is also close to the optimal solution obtained by Integer Linear Programming (ILP).

Orchestrating incomplete TOSCA applications with Docker

Cloud applications typically integrate multiple components, each needing a virtualised runtime environment that provides the required software support (e.g., operating system, libraries). This paper shows how TOSCA and Docker can effectively support the orchestration of multi-component applications, even when their runtime specification is incomplete. More precisely, we first introduce a TOSCA-based representation of multi-component applications, and we illustrate how such representation can be exploited to specify only the application-specific components. We then present TosKeriser , a tool for automatically completing TOSCA application specifications, which can automatically discover the Docker-based runtime environments that provide the software support needed by the application components. We also show how we fruitfully exploited TosKeriser in two concrete case studies. Finally, we discuss how the specifications completed by TosKeriser can be automatically orchestrated by already existing TOSCA engines. • We present a TOSCA-based representation of multi-component applications. • Our representation permits specifying only application-specific components. • We present TosKeriser, a tool to automatically complete TOSCA specifications. • Automatically completed specifications can be executed by existing TOSCA engines. • We discuss the usefulness of TosKeriser by means of two concrete case studies.

Hierarchical and Parallel Pipelined Heterogeneous SoC for Embedded Vision Processing

Object recognition is widely used in vision computing for various applications. Traditional CPU and application specific integrated circuit for vision computing cannot provide high performance and enough flexibility, which limit the use of vision systems. In this paper, a hierarchical and parallel pipelined heterogeneous chip for object recognition is proposed to achieve high flexibility, high performance, and area efficiency. In addition, a reformulation of 3D position estimation is proposed. The method uses single precision to achieve the short computing time and accuracy requirement. The hardware resource is small. Application-specific components, such as connected component information extractor and information extraction accelerator, are designed for high performance. Reconfiguration processors and application-specific instruction set processor are introduced to improve flexibility. These components are connected to hierarchical parallel buses. The chip is fabricated in 180-nm CMOS technology and occupies 72.25 mm2 with 1.09M bits on-chip memory. It delivers 204 GOPS + 665M FLOPS operations. The results show that this hierarchical and parallel pipelined heterogeneous chip is suitable for embedded vision systems.

A Novel MPSoC Interface and Control Architecture for Multistandard RF Transceivers

The introduction of new mobile communication standards, enabling the ever growing amount of data transmitted in mobile communication networks, continuously increases the complexity of control processing within radio frequency (RF) transceivers. Since this complexity cannot be handled by traditional approaches, this paper focuses on the partitioning of RF transceiver systems and on the implementation of application-specific components to introduce an advanced multiprocessor system-on-chip interface and control architecture which is able to fulfill the requirements of future RF transceiver integrations. The proposed framework demonstrates a high degree of scalability, flexibility, and reusability. Consequently, the time to market for products can be reduced and fast adaptations to the requirements of the market are feasible. In addition, the developed application-specific components achieve improved or at least equivalent performance results compared with common architectures while the silicon area can be reduced. This characteristic has positive effects on the costs as well as on the power consumption of the RF transceiver.

Flight Test Results of a Measurement-Based ADS-B System for Separation Assurance

ABSTRACT: Future Aircraft Surveillance Applications (ASA) systems for situational awareness applications (e.g.,conflict detection and resolution, final approach and runway occupancy awareness, and airport surface situationalawareness methods), airborne spacing applications, airborne separation applications, and self-separationapplications will benefit from the introduction of Automatic Dependent Surveillance-Broadcast (ADS-B). Analternative ADS-B implementation, which transmits measurements from the Global Navigation SatelliteSystem (GNSS) instead of aircraft state vectors and performance parameters in the current implementation, hasbeen proposed previously to improve surveillance performance. This paper summarizes the proposedmethodology, discusses its threat models and integrity aspects, and presents the initial flight test results of thisalternative ADS-B implementation, along with a performance analysis. Copyright # 2013 Institute of Navigation INTRODUCTIONTo meet the expanding demand of air traffic in theNational Airspace System (NAS), an increase incapacity will be required. Efforts to achieve thischange in capacity are directed and overseen bythe Joint Planning and Development Office (JPDO)formed by the Federal Aviation Administration(FAA), the National Aeronautics and SpaceAdministration (NASA), and several othergovernment agencies. The resulting improved airtransportation system is referred to as the NextGeneration Air Transportation System or NextGen.When completed NextGen is supposed to “providethe capacity required to meet the nation’sneedinthemost effective, efficient, safe, and secure mannerpossible” [1, 2]. Meanwhile, Europe has been workingon an equivalent transformation of European airspace through the Single European Sky Air TrafficManagement (ATM) Research (SESAR) [3].The goals of NextGen are to significantly increasethe safety, security, capacity, efficiency, andenvironment compatibility of aviation operations inthe NAS. In order to achieve increased capacityand efficiency in an even more congested NAS, manydecisions in NextGen will be made at a local levelwith an awareness of system-wide implications.Intermsofsurveillance,NextGenenvisionsdelegatedseparation, which transfers certain responsibilityfor separation from ATM to flight crews to ensurethat the applicable airborne separation minimaare met. In particular, two of the eight identi fiedkey capabilities of NextGen, Performance-BasedOperations and Services (PBO) and Aircraft Trajectory-Based Operations (TBO), will help facilitate aircraftusingtheir4-Dflightprofilesandperformance-relatedparameters to enable reduced separation andincreased trajectory predictability [1].The Aircraft Surveillance Applications (ASA)systems are expected to provide the abovementionedimproved situational awareness. As the surveillanceand application-specific component of the ASAsystems, Airborne Surveillance and SeparationAssurance Processing (ASSAP) is intended tointegrate information from all the NextGenCommunication, Navigation, and Surveillance (CNS)systems to perform surveillance applicationssuch as enhanced visual acquisition, conflictdetection and resolution, airport surface situationalawareness, final approach and runway occupancyawareness, and enhanced visual approach, and topresent trafficstateinformationtoflight crewsthrough a Cockpit Display of TrafficInformation(CDTI) atleastseveralminutesaheadofapredictedloss of separation [4, 5].

Editorial for CollaborateCom 2011 Special Issue

Editorial: Collaboration is an essential cornerstone of modern computing. Enabled by cloud computing, new wireless networks, ubiquitous mobile devices – to name just a few – the new collaborative ecosystem promises a potential that far exceeds our current capabilities. And as the world heads towards unlimited connectivity and global mobile computing, future collaboration solutions that fully realize this potential will require advances in networking, technology and systems, user interfaces and interaction paradigms, and interoperation with application-specific components and tools. As a nexus for collaborative computing, the Seventh International Conference on Collaborative Computing: Networking, Applications and Worksharing (CollaborateCom 2011) serves as a premier international forum for discussion among academic and industrial researchers, practitioners, and students interested in collaborative networking, technology and systems, and applications. In total, we received 62 submissions to CollaborateCom 2011. After a rigorous review and follow-up discussions, the Program Committee selected 19 papers for acceptance (a rate of 30 %). Following the completion of the conference, the Program Committee selected three of the best papers from the conference that best exemplify the themes of CollaborateCom and mobile computing for special invited submission to this issue. These three papers underwent a series of new reviews and revisions before appearing as you will find them here. In the first paper titled “Data Replication in Cooperative Mobile Ad-Hoc Networks: A game theoretic replication algorithm using volunteers' dilemma,” Hirsch and Madria propose a new replication scheme to strategically balance the constrained resources inherent in a mobile computing environment through a cooperative game theoretic approach. Nodes within the network collaborate via cooperative replica caching decisions to achieve overall improved query response times while reducing the query error rate and energy utilization. The second paper titled “Combining Mobile XMPP Entities and Cloud Services for Collaborative Post-Disaster Management in Hybrid Network Environments,” by Klauck and Kirsche presents a new system design that integrates portable devices and autonomous sensors through XMPP with the flexibility of cloud services to support post-disaster management. Through implementation and evaluation of two prototypes, they derive new insights into the practical application of XMPP and potential enhancements in hybrid (ad hoc and infrastructure) network scenarios. In the third paper titled “ChameleonSoft: Software Behavior Encryption For Moving Target Defense,” Azab and Elotweissy propose a biologically-inspired defense system that employs multidimensional software diversity to overcome the vulnerability of the persistent software monoculture. The system – ChameleonSoft – is built over a celloriented architecture, applying a multidimensional spatiotemporal diversity and hot shuffling of variants, hence effecting software execution behavior encryption, as well as adjusting its system policies at runtime to meet the continual change in the operational environment. As you read this issue, we believe you'll find that the selected papers make significant contributions to J. Caverlee (*) Department of Computer Science and Engineering, Texas A&M University, College Station, TX, USA e-mail: caverlee@cse.tamu.edu

A Path Analysis of the Impact of Application-Specific Perceptions of Computer Self-Efficacy and Anxiety on Technology Acceptance

Perceptions of computer self-efficacy (CSE) and computer anxiety are valuable predictors of various computer-related behaviors, including acceptance and utilization of information systems (IS). Although both factors are purported to have general and application-specific components, little research has focused on the application or system-specific component, especially in IS acceptance contexts. Thus, little is known about the effects of application-specific beliefs on IS acceptance or how such effects compare with the effects of more general CSE and computer anxiety beliefs. Accordingly, a research model comprising application CSE, application anxiety, perceived ease of use, perceived usefulness, attitude, and intention was proposed and tested via path analysis. The results demonstrated that the direct impacts of application CSE and application anxiety on perceived ease of use and perceived usefulness were almost equal, but in opposite directions. However, the indirect effect of application CSE on attitude and intention was stronger than that of application anxiety.

Design and implementation of an ASIC-based sensor device for WSN applications

The practical applications of wireless sensor networks require the sensor devices to be high in computation ability, low in power consumption, small in size, as well as competitive in cost. In addition, there are other particular attributes which require special consideration in sensor device design. These include, for example, the capabilities in protecting the embedded program from foreign intrusion and supporting efficient air-programming, which are very common requirements in many large-scale applications. In this paper, we describe the system architecture and design methodology of an ASCI-based sensor network device to meet those attributes for a class of applications. Compared with existing works, the unique features of the sensor device include: (1) a module-based extensible processor and co-processor cooperation architecture is designed with application-specific components to accelerate the signal collection, processing, and networking via hardware-software co-design to balance computation efficiency and design flexibility; (2) a program protection mechanism is developed based on un-resemble coder algorithm to protect the program data from being read out by system intruders so as to improve the security of the sensor device; (3) an air-programming component is proposed to enable an efficient remote programming which is a very common requirement in network deployment and maintenance. In this paper, we present the design, implementation, and evaluation of the prototype sensor device based on a general configurable FPGA platform for developing next-generation sensor devices. Initial results of the first version of prototype chip will also be introduced.

A knowledge-based system for the non-destructive diagnostics of façade isolation using the information fusion of visual and IR images

This paper describes a knowledge-based system for the non-destructive diagnostics of façade isolation. The system uses the fusion of information extracted from images obtained from two electromagnetic wavebands: from low-resolution IR images (320 × 240 pixels; 7.5–13 μm wavelength), and from high-resolution visual RGB images (3264 × 2448 pixels; 0.39–0.75 μm wavelength). The fusion of the information is a perquisite for the design of an efficient knowledge-based system for non-destructive testing and façade diagnostics. In the paper, special attention is devoted to the following knowledge-based system components: system-core components (the database, the knowledge base, the inference engine, and the user interface) and application-specific components (image acquisition, the resolution pyramid, image pre-processing and feature extraction, image registration, object segmentation, fusion, and data analysis). Examples of the non-destructive testing and the façade diagnostics obtained with the system are presented.

ProbeMaker: an extensible framework for design of sets of oligonucleotide probes

BackgroundProcedures for genetic analyses based on oligonucleotide probes are powerful tools that can allow highly parallel investigations of genetic material. Such procedures require the design of large sets of probes using application-specific design constraints.ResultsProbeMaker is a software framework for computer-assisted design and analysis of sets of oligonucleotide probe sequences. The tool assists in the design of probes for sets of target sequences, incorporating sequence motifs for purposes such as amplification, visualization, or identification. An extension system allows the framework to be equipped with application-specific components for evaluation of probe sequences, and provides the possibility to include support for importing sequence data from a variety of file formats.ConclusionProbeMaker is a suitable tool for many different oligonucleotide design and analysis tasks, including the design of probe sets for various types of parallel genetic analyses, experimental validation of design parameters, and in silico testing of probe sequence evaluation algorithms.

A decoupled scheduling approach for Grid application development environments

In this paper we propose an adaptive scheduling approach designed to improve the performance of parallel applications in Computational Grid environments. A primary contribution of our work is that our design is decoupled, thus providing a separation of the scheduler itself from the application-specific components needed for the scheduling process. As part of the scheduler, we have also developed an application-generic resource selection procedure that effectively and efficiently identifies desirable resources. As test cases for our approach, we selected two applications from the class of iterative, mesh-based applications. We used a prototype of our approach with these applications to perform validation experiments in production Grid environments. Our results show that our scheduler, albeit decoupled, provides significantly better application performance than conventional scheduling strategies. We also show that our scheduler gracefully handles degraded levels of availability of application and Grid resource information. Finally, we demonstrate that the overhead associated with our methodology is reasonable. This work evolved in the context of the Grid Application Development Software Project (GrADS). Our approach has been integrated with other GrADS software tools and, in that context, has been applied to three real-world applications by other members of the project.

A flexible, extensible simulation environment for testing real-time specifications

This paper describes MTSim, an extensible, customizable simulation platform for the Modechart toolset (MT). MTSim provides support for plugging user-defined viewers useful in simulating system behavior in different ways, including application-specific ways. MTSim also supports full user participation in the generation of simulations by allowing users to inject events into the execution trace. Moreover, MTSim provides monitoring and assertion checking of execution traces and the invocation of user-specified handlers upon assertion violation. This paper also introduces an MTSim component called WebSim, a suite of simulation tools for MT, and an application-specific component of MTSim which displays the cockpit of an F-18 aircraft and which responds to user inputs to model a bomb release function.

Designing a neural network simulator—the MENS modelling environment for network systems: II

During recent years, neural network research has been extended to a large number of different fields, increasingly attracting the interest of workers from various disciplines. The computer simulations carried out with this research require an appropriate software environment. The computational similarities of many kinds of simulations allow the design of software components that are largely independent of the specific application. These considerations are reflected, for example, by the general layout of the MENS network simulator, as described in the accompanying first paper. This paper presents the design considerations for the simulator's different software components in more detail. In particular, design and implementation are discussed with respect to computational and memory efficiency. The discussion includes, for example, the representation of a network by the simulator's data structure, the file-driven configuration and initialization of a network, the simulator's stimulus and monitor system, and the simulator's control structures. In addition, the separation and interaction of application-specific and application-independent software components are addressed. Particular performance aspects comprise the implementation of synaptic delays, the dynamic deletion of synaptic links in network learning, and the preprocessing of stimulus films. In addition, some general aspects of simulator performance and testing are considered. The material presented in this paper concerns both the development of new simulation software and the efficient use of existing programs. Therefore, both the general user as well as the software designer may hopefully benefit from this presentation.