This paper outlines an architecture that provides data and software services to enable a set of Unmanned Aircraft (UA) platforms to operate in a wide range of air domains which may include terminal, en route, oceanic and tactical. The architecture allows a collection of command,control, situational awareness, conflict detection and avoidance, and data management elements to be composed in order to meet different requirement sets as defined by specific UA platforms, users, and operating regimes. The architecture discussed is based on a Service Oriented Architecture (SOA) with open standards on the interfaces between elements. Services may include common situational awareness, sense and avoid,weather, data management and flight plan information. Service contracts specify quality of service,interface specifications, service description metadata, security provisions, and governance. Pieces of the architecture have been implemented by MIT Lincoln Laboratory in the form of a Sense and Avoid (SAA) testbed that provides some of the core services. This paper describes the general architecture and a SAA testbed implementation that begins to realize that architecture and quantifies the benefits. The proposed architecture is not directed at a specific program but is intended to provide guidance and offer architectural best practices.

关键词：电子信息；软件；系统；集成

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Gun-launched munitions rely heavily on the global positioning system (GPS) receivers for position, velocity, and “up-finding” in their guidance, navigation, and control (GN&C) systems. These receivers account for substantial cost in the GN&C electronics due to the contractor intellectual property and non-recurring engineering (NRE) costs. Typically, the designs are not optimized for gun-launched munitions, but rather as general purpose receivers for missiles, unmanned aerial vehicles, aircraft, man-portable location systems, and vehicles. Due to the high launch dynamics, short time of flight, high spin rate, etc., the general purpose receivers have trouble acquiring and locking on the weak GPS signals. To address these challenges, software algorithms tailored to the flight dynamics can assist in the basic features of the receiver as well as provide jamming and spoofing immunity. In this report, a software-defined radio (SDR) approach is used for the development of global navigation satellite systems (GNSS) receivers. This approach provides an evaluation capability for algorithm development and evaluation that is nearly hardware agnostic.

关键词：电子信息；软件；定位系统；框架

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The NEAMS IPSC's are developing multidimensional, multiphysics, multiscale simulation codes based on first principles that will be capable of predicting all aspects of current and future nuclear reactor systems. These new breeds of simulation codes will include rigorous verification, validation and uncertainty quantification checks to quantify the accuracy and quality of the simulation results. The resulting NEAMS IPSC simulation codes will be an invaluable tool in designing the next generation of Nuclear Reactors and also contribute to a more speedy process in the acquisition of licenses from the NRC for new Reactor designs. Due to the high resolution of the models, the complexity of the physics and the added computational resources to quantify the accuracy/quality of the results, the NEAMS IPSC codes will require large HPC resources to carry out the production simulation runs.

关键词：电子信息；软件；堆栈；NEAMS

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The objective of this technical note is to demonstrate, by way of example(s), how to use the Engineer Research and Development Center (ERDC) implementation of the Levenberg-Marquardt (LM) and Secant LM (SLM) method for model independent parameter estimation to calibrate a Gridded Surface Subsurface Hydrologic Analysis (GSSHA) hydrologic model. The purpose is not to present or focus on the theory which underlies the parameter estimation method(s), but rather to carefully describe how to use the ERDC software implementation of the secant LM method that accommodates the PEST model independent interface to calibrate a GSSHA hydrologic model. We will consider variations of our Secant LM (SLM) implementation in attempts to provide the interested reader with an intuitive sense of how the method works. We will also demonstrate how our LM/SLM implementation compares with its counterparts as implemented in the popular PEST software.

关键词：电子信息；软件；水文模型；校准

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Scientific data services are becoming an important part of the NASA Center for Climate Simulation's mission. Our technological response to this expanding role is built around the concept of a Virtual Climate Data Server (vCDS), repetitive provisioning, image-based deployment and distribution, and virtualization-as-a-service. The vCDS is an iRODS-based data server specialized to the needs of a particular data-centric application. We use RPM scripts to build vCDS images in our local computing environment, our local Virtual Machine Environment, NASA s Nebula Cloud Services, and Amazon's Elastic Compute Cloud. Once provisioned into one or more of these virtualized resource classes, vCDSs can use iRODS s federation capabilities to create an integrated ecosystem of managed collections that is scalable and adaptable to changing resource requirements. This approach enables platform- or software-asa- service deployment of vCDS and allows the NCCS to offer virtualization-as-a-service: a capacity to respond in an agile way to new customer requests for data services.

关键词：电子信息；软件；气候；服务器

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Benchmarking was very interesting and provided a wealth of information (1) We did see potential solutions to some of our "top 10" issues (2) We have an assessment of where NASA stands with relation to other aerospace/defense groups We formed new contacts and potential collaborations (1) Several organizations sent us examples of their templates, processes (2) Many of the organizations were interested in future collaboration: sharing of training, metrics, Capability Maturity Model Integration (CMMI) appraisers, instructors, etc. We received feedback from some of our contractors/ partners (1) Desires to participate in our training; provide feedback on procedures (2) Welcomed opportunity to provide feedback on working with NASA.

关键词：电子信息；软件；航空；测试

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BRIEF DESCRIPTION OF PORTFOLIO: Enable quantifiable performance evaluation of critical software systems. Manage software environments in order to preserve vital mission functions. Comprehensively understand distributed effects in large software infrastructures to predict global system failures. LIST SUB-AREAS IN PORTFOLIO: Models for Composeable Dynamic Software. Dynamic Formal Analysis and Verification. Online Assessment and Repair of Failure.

关键词：电子信息；软件；系统

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The SGOS executive and its subsystems have been an integral component of the Shuttle Launch Safety Program for almost thirty years. it is usable (via the LAN) by over 2000 NASA employees at the Kennedy Space Center and 11,000 contractors. SGOS supports over 800 models comprised of several hundred thousand lines of code and over 1,00 MCP procedures. Yet neither language has a for loop. The simulation software described in this paper is used to train ground controllers and to certify launch countdown readiness.

关键词：电子信息；软件；航天；架构

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In November 2006, after attempting to make a routine maneuver, NASA's Mars Global Surveyor (MGS) reported unexpected errors. The onboard software switched to backup resources, and a 2-day lapse in communication took place between the spacecraft and Earth. When a signal was finally received, it indicated that MGS had entered safe mode, a state of restricted activity in which the computer awaits instructions from Earth. After more than 9 years of successful operation gathering data and snapping pictures of Mars to characterize the planet's land and weather communication between MGS and Earth suddenly stopped. Months later, a report from NASA's internal review board found the spacecraft's battery failed due to an unfortunate sequence of events. Updates to the spacecraft's software, which had taken place months earlier, were written to the wrong memory address in the spacecraft's computer. In short, the mission ended because of a software defect. Over the last decade, spacecraft have become increasingly reliant on software to carry out mission operations. In fact, the next mission to Mars, the Mars Science Laboratory, will rely on more software than all earlier missions to Mars combined. According to Gerard Holzmann, manager at the Laboratory for Reliable Software (LaRS) at NASA's Jet Propulsion Laboratory (JPL), even the fault protection systems on a spacecraft are mostly software-based. For reasons like these, well-functioning software is critical for NASA. In the same year as the failure of MGS, Holzmann presented a new approach to critical software development to help reduce risk and provide consistency. He proposed The Power of 10: Rules for Developing Safety-Critical Code, which is a small set of rules that can easily be remembered, clearly relate to risk, and allow compliance to be verified. The reaction at JPL was positive, and developers in the private sector embraced Holzmann's ideas.

关键词：电子信息；软件；可靠性；工具

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Software-defined radios (SDRs) provide researchers with a powerful and flexible wireless communications experimentation platform. GNU Radio is the most popular open-source software toolkit for deploying SDRs, and is frequently used with the Universal Software Radio Peripheral (USRP). After establishing a USRP testbed, the researcher will need to implement new signal processing algorithms or modify existing ones. This document describes this process, highlighting those details that have received minimal attention in the existing documentation.

关键词：电子信息；软件；无线电；信号处理

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