This document describes the design, construction, and testing of a proof-of-concept hardware and software package that combines cognitive radio and autonomous vehicles in a single system whose behavior captures the essential features of both. The result is a low-cost (less than $200) cognitive radio and cognitive engine package suitable for installation in the small experimental UAVs flown by USAFRL. Experiments with the package controlling a small wheeled vehicle demonstrate its ability to explore and learn a multidimensional environment that combines changing RF, location, and mission data and to optimize its mission performance intelligently.

关键词：自适应系统；自主导航；无人机；情景意识；发射接收器

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Memory content similarity has been effectively exploited for more than a decade to reduce memory consumption. By consolidating duplicate and similar pages in the address space of an application, we can reduce the amount of memory it consumes without negatively affecting the application's perception of the memory resources available to it. In addition to memory de-duplication, there may be many other ways that we can exploit memory content similarity to improve system characteristics. In this paper, we examine the memory content similarity of several HPC applications. By characterizing the memory contents of these applications, we hope to provide a basis for efforts to effectively exploit memory content similarity to improve system performance beyond memory deduplication. We show that several applications exhibit significant similarity and consider the source of the similarity.

关键词：存储设备；计算机应用；整合；相似性

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As computing systems grow to exascale levels of performance, the smallest elements of a single processor can greatly affect the entire computer system (e.g. its power consumption). As future generations of processors are developed, simulation at the gate level is necessary to ensure that the necessary target performance benchmarks are met prior to fabrication. The most common simulation tools available today utilize either a single node or small clusters and as such create a bottleneck in the development process. This paper focuses on the massively parallel simulation of logic gate circuit models using supercomputer systems. The focus of this performance study leverages the OpenSPARC T2 processor design and the PHDOLD benchmark model using Rensselaer s Optimistic Simulation System (ROSS). We conduct simulations of the crossbar component on a 24-core SMP machine, an IBM Blue Gene/L, and an IBM Blue Gene/Q. Using a single SMP core as the baseline, our performance experiments on 1024 cores of the Blue Gene/L demonstrate more than 131-times faster execution of the OpenSPARC model. We also present the performance results of ROSS executing the Time Warp synchronization protocol using up to 7.8M MPI tasks on 1,966,080 cores of the Sequoia Blue Gene/Q supercomputer system. For the PHOLD benchmark model, we demonstrate the ability to process 33 trillion events in 65 seconds yielding a peak event-rate in excess of 504 billion events/second using 120 racks of Sequoia.

关键词：并行处理器；聚类；计算机；节点；加工设备

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A high fidelity simulation using a PC based Trick framework has been developed for Johnson Space Center's Morpheus test bed flight vehicle. There is an iterative development loop of refining and testing the hardware, refining the software, comparing the software simulation to hardware performance and adjusting either or both the hardware and the simulation to extract the best performance from the hardware as well as the most realistic representation of the hardware from the software. A Particle Swarm Optimization (PSO) based technique has been developed that increases speed and accuracy of the iterative development cycle. Parameters in software can be automatically tuned to make the simulation match real world subsystem data from test flights. Special considerations for scale, linearity, discontinuities, can be all but ignored with this technique, allowing fast turnaround both for simulation tune up to match hardware changes as well as during the test and validation phase to help identify hardware issues. Software models with insufficient control authority to match hardware test data can be immediately identified and using this technique requires very little to no specialized knowledge of optimization, freeing model developers to concentrate on spacecraft engineering. Integration of the PSO into the Morpheus development cycle will be discussed as well as a case study highlighting the tool's effectiveness.

关键词：计算机模拟；优化；试验台；全自动控制；航空航天器

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We introduce a novel method for selecting and controlling smart appliances in physical spaces through a head-worn computing device with near-eye display and wireless communication. We augment a commercial wearable computing device, Google Glass, with a narrow-beam infrared emitter for this purpose. This configuration yields a usable beam width of 2 to 4 feet (60 to 120 cm) for targeting at room scale. We describe a disambiguation technique if infrared targeting hits multiple targets simultaneously. A target acquisition study with 14 participants shows that selection using head orientation with our device outperforms list selection on a wearable device. We also report qualitative data from using our device to control multiple appliances in a smart home scenario.

关键词：帽子；红外线设备；移动计算；远程控制

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In order to obtain maximum battery lifetime and efficient operation, rechargeable batteries require unique charging profiles with an end-state, low current trickle charge. The series loaded resonant (SLR) charging system presented in this thesis meets the needs of an efficient, sensor integrated, and galvanically isolated trickle charger. The SLR DC-DC converter was successfully modeled in Simulink, and simulation results are verified in a laboratory application. The Simulink model and hardware are tested at several operating points. Component stresses are quantified and weak points are identified.

关键词：电池充电器；转换器；蓄电池

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Energy harvesting is being investigated as an alternative to batteries for powering various Army systems. A piezoelectric system that generates energy from the oscillation of a mass on a spring (set in motion by the launch acceleration) is being developed. Typically, this energy is stored on an electrolytic capacitor for use during flight. Here we investigate a number of electrolytic capacitors and electrochemical double layer capacitors (aka, supercapacitors) for storing this energy. Supercapacitors are of interest, as they are potentially smaller, lighter, and more reliable. Here, we have investigated capacitors of different sizes as well as fast and slow supercapacitors for storing the energy. We find that capacitors of similar size store similar amounts of energy, with a system-dependant optimum size for maximum stored energy, and that the faster capacitors charge more quickly.

关键词：电容器；能量收获；蓄电池

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Recent studies of missions to the Moon, Mars and Near Earth Asteroids (NEA) indicate that these missions often involve several distinct separately launched vehicles that must ultimately be integrated together in-flight and operate as one unit. Therefore, it is important to see these vehicles as elements of a larger segmented spacecraft rather than separate spacecraft flying in formation. The evolution of large multi-vehicle exploration architecture creates the need (and opportunity) to establish a global power architecture that is common across all vehicles. The Advanced Exploration Systems (AES) Modular Power System (AMPS) project managed by NASA Glenn Research Center (GRC) is aimed at establishing the modular power system architecture that will enable power systems to be built from a common set of modular building blocks. The project is developing, demonstrating and evaluating key modular power technologies that are expected to minimize non-recurring development costs, reduce recurring integration costs, as well as, mission operational and support costs. Further, modular power is expected to enhance mission flexibility, vehicle reliability, scalability and overall mission supportability. The AMPS project not only supports multi-vehicle architectures but should enable multi-mission capability as well. The AMPS technology development involves near term demonstrations involving developmental prototype vehicles and field demonstrations. These operational demonstrations not only serve as a means of evaluating modular technology but also provide feedback to developers that assure that they progress toward truly flexible and operationally supportable modular power architecture.

关键词：航空航天系统；降低成本；灵活性；编队飞行

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Because of its simple structure, high density and good scalability, resistive random access memory (RRAM) is expected to be a promising candidate to substitute traditional data storage devices, e.g., hard-disk drive (HDD). In a conventional three-dimensional (3D) bipolar RRAM design, an isolation layer is inserted between two adjacent memory layers. The fabrication of the isolation layer introduces the extra process complexity, increases fabrication cost, and causes some potential reliability issues. In this paper, we propose a 3D High-density Interleaved Memory (3D-HIM) design for bipolar RRAM, which can eliminate the need for forming isolation layers and further improve the density of the memory island. Meanwhile, we propose a Bi-Group Operation Scheme for 3D- HIM to access multiple cells among multiple layers and to avoid unexpected overwriting. The simulation results show that the proposed design is promising for a 3D stacking RRAM application with acceptable operation margin for a 32 x 32 x 8 array in a memory island. The sensing margin degradation and programming bias confine the size of the array due to sneak path conducting currents. We diminish impact of sneak path conducting current by applying a high Ron RRAM device which can be achieved by a small-scale RRAM device.

关键词：计算机存储；数据存储系统；三维

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Mercury cadmium telluride (HgCdTe) alloy is of great importance to infrared sensing, and much of the research and development work is carried out for cooled operations. At ambient temperatures, intrinsic carriers are dominant, resulting in high dark currents. This technical report describes ways to reduce intrinsic carriers in ambient temperatures and, in particular, addresses reducing minority carriers in non-equilibrium operation under reverse biases.

关键词：长波长；汞镉碲化物；光电电池（半导体）；砷

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