The aluminum nanoparticles (Al NPs) are demonstrated to serve as active photothermal media, to enhance and control local photothermal energy deposition via the photothermal effect activated by localized surface plasmon resonance (LSPR) and amplified by Al NPs oxidation. The activation source is a 2-AA-battery-powered xenon flash lamp. The extent of the photothermally activated movement of Al NPs can be approx. 6 mm. Ignition delay can be approx. 0.1 ms. Both scanning electron microscopy and energy-dispersive X-ray spectroscopy measurements of motion-only and after-ignition products confirm significant Al oxidation occurs through sintering and bursting after the flash exposure. Simulations suggest local heat generation is enhanced by LSPR. The positive- feedback effects from the local heat generation amplified by Al oxidation produce a large increase in local temperature and pressure, which enhances movement and accelerates ignition.

关键词：电池能源；光热光谱分析；等离子体

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No abstract available.

关键词：气闸舱模块；二氧化碳；舱外活动；飞行运行

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In order to collaborate engineering designs among NASA Centers and customers, to in clude hardware and human activities from multiple remote locations, live human-centered modeling and collaboration across several sites has been successfully facilitated.

关键词：环境工程；生物力学；设计分析；显示设备

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The use of biometric devices has become critical to implementing various forms of security in a large number of organizations worldwide. The current state of biometric sensor integration is labor intensive and prone to interoperability issues because of proprietary hardware and software, and a lack of standards in the Software Development Kit (SDK) installation process. Sensor integration incorporates the device hardware installation and intricate patchwork necessary to facilitate full communication between the devices software and the application that will ultimately command and control the target sensor. This document describes a process used to achieve more flexible and reliable integration of biometric sensor SDKs into the application development process. It is intended for two audiences. First, for developers, it provides an analysis of the typical biometric SDK installation process and guidelines on how to increase reliability and repeatability of the SDK installation process, with an emphasis on separating the compile-time and run-time resources. Second, for biometric sensor providers, it suggests a specific set of resources to be distributed in SDKs that allow developers to access SDK components as well as obtain details pertinent to the use and maintenance of their biometric sensor solutions. Both audiences are encouraged to use the document as informative guidance to help develop and improve their own processes; readers are encouraged to adapt, modify, or evolve content to suit their own context of use.

关键词：生物识别技术；指挥和控制；计算机通信；计算机硬件

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A concurrent system is persistent if throughout its operation no activity which became enabled can subsequently be prevented from being executed by any other activity. This is often a highly desirable (or even necessary) property; in particular, if the system is to be implemented in hardware. Over the past 40 years, persistence has been investigated and applied in practical implementations assuming that each activity is a single atomic action which can be represented, for example, by a single transition of a Petri net. In this paper we investigate the behaviour of GALS (Globally Asynchronous Locally Synchronous) systems in the context of VLSI circuits. The specification of a system is given in the form of a Petri net. Our aim is to re-design the system to optimise signal management, by grouping together concurrent events. Looking at the concurrent reachability graph of the given Petri net, we are interested in discovering events that appear in 'bundles', so that they all can be executed in a single clock tick. The best candidates for bundles are sets of events that appear and re-appear over and over again in the same configurations, forming 'robust' sets of events. Persistence was considered so far only in the context of sequential semantics. In this paper, we move to the realm of step based execution and consider not only steps which are persistent and cannot be disabled by other steps, but also steps which are nonviolent and cannot disable other steps. We then introduce a formal definition of a bundle and propose an algorithm to prune the behaviour of a system, so that only bundle steps remain. The pruned reachability graph represents the behaviour of a re-engineered system, which in turn can be implemented in a new Petri net using the standard techniques of net synthesis. The proposed algorithm prunes reachability graphs of persistent and safe nets leaving bundles that represent maximally concurrent steps.

关键词：异步电路；计算机硬件；非暴力；持久性

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Objective: To develop a software application utilizing general purpose graphics processing units (GPUs) for the analysis of large sets of thermographic data. Background: Over the past few years, an increasing effort among scientists and engineers to utilize the GPU in a more general purpose fashion is allowing for supercomputer level results at individual workstations. As data sets grow, the methods to work them grow at an equal, and often greater, pace. Certain common computations can take advantage of the massively parallel and optimized hardware constructs of the GPU to allow for throughput that was previously reserved for compute clusters. These common computations have high degrees of data parallelism, that is, they are the same computation applied to a large set of data where the result does not depend on other data elements. Signal (image) processing is one area were GPUs are being used to greatly increase the performance of certain algorithms and analysis techniques.

关键词：图像处理；大规模并行处理器；热成像

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关键词：模拟系统；电路；突触；纳米技术；模式识别

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Complex scientific software is often built on distributions , or stacks , of software. Particulary as scientists and engineers work toward more integrated, and therefore more interdependennt, scientific software, they need the ability to setup scientific stacks in many different user and hardware environments and hardware. Scientific stacks must be reproducible in the sense that regular users should be able to install them and have them work as advertised. These stacks also need to work in challenging environments like cutting edge high performance commputers and handheld devices. Due to the authors separate but similar experiences of the difficulty of buiding and maintaining scientific software stacks to support our own work, we worked together to build Hashdist, which is a a tool for building and managing custom software distributions based on a functional approach. It employs cryptographic hashing methods related to what are used in highly successful software source version control system to bring the same robustness to building and developing complex scientific software stacks.

关键词：计算机程序；控制系统；加密；分布；堆垛

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The Intelligence, Surveillance, and Reconnaissance (ISR) Technology Integration Branch of the U.S. Army Research Laboratory (ARL) in support of persistent surveillance missions has developed a low-power acoustic detector (LPAD). The motivation for this work focused on the development of a system to detect targets with internal combustion engines, which include vehicles, boats, aircraft, and generators, while having an operational life greater than one year on a single AA lithium battery. The LPAD will serve as a wake-up trigger for larger and more power consuming sensors and algorithms such as imagers, array signal processors etc. This report details the hardware design, target detection algorithm design in both MATLAB and VHDL, and typical performance results.

关键词：声学探测器；现场可编程门阵列；算法；面包板模型

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Matrix multiplication is one of the most fundamental algorithmic problems in numerical linear algebra, distributed computing, scientific computing, and high-performance computing. Parallelization of matrix multiplication has been extensively studied (e.g., 21, 12, 24, 2, 51, 39, 36, 23, 45, 61). It has been addressed using many theoretical approaches, algorithmic tools, and software engineering methods in order to optimize performance and obtain faster and more efficient parallel algorithms and implementations. To design efficient parallel algorithms, it is necessary not only to load balance the computation, but also to minimize the time spent communicating between processors. The interprocessor communication costs are in many cases significantly higher than the computational costs. Moreover, hardware trends predict that more problems will become communication-bound in the future 38, 35. Even matrix multiplication, which is widely considered to be computation-bound, becomes communication-bound when a given problem is run on sufficiently many processors.

关键词：算法；分布式数据处理;；软件工程

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