This is the final report for a grant covering research across a broad domain of metamaterial-based antenna research at the visible and near- infrared range (600nm to 2000nm), culminating in 38 peer-reviewed papers. The research covers elements of metamaterial-based antennas and antenna arrays in semiconductor devices, attempting to understand geometric effects of the unit cell on metamaterial performance and then translating this knowledge into design principles. The metamaterial-based antenna research is divided into five broad sub-areas: resonance tuning for concave antennas, capacitive versus conductive coupling, on-demand design (termed 'popcorn' antennas), broadband plasmonic metamaterials, and light focusing/energy harvesting by plasmonic antennas. The research on antenna arrays is divided into enhancement of organic solar cells by antenna arrays, applications of antenna arrays to speed LED response, current injection using antenna metamaterials, and the implementation of an enhanced short-wave infrared (SWIR) quantum cascade detector.

关键词：天线；Eoard；国外报道；以色列；超材料

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The Debye sheath is shown to be unstable under general conditions. For surface materials with sufficient secondary electron emission (SEE) yields, the surface's current-voltage characteristic has an unstable branch when the bulk plasma temperature (Te ) exceeds a critical value, or when there are fast electron populations present. The plasma-surface interaction becomes dynamic where the sheath may undergo spontaneous transitions or oscillations. Using particle-in-cell simulations, we analyze sheath instabilities occurring in a high Te plasma slab bounded by walls with SEE. As the plasma evolves, whenever the sheath enters an unstable state, its amplitude rapidly collapses, allowing a large flux of previously trapped electrons to hit the wall. These hot electrons induce more than one secondary on average, causing a net loss of electrons from the wall. The sheath collapse quenches when the surface charge becomes positive because the attractive field inhibits further electrons from escaping. Sheath instabilities influence the current balance, energy loss, cross-B-field transport and even the bulk plasma properties. Implications for discharges including Hall thrusters are discussed. More generally, the results show that common theories that treat emission as a fixed (time-independent) 'coefficient' do not capture the full extent of SEE effects.

关键词：等离子鞘；电子；倒塌；排放；不稳定性

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Free-standing carbon nanotube (CNT) electrodes were developed as suitable light-weight current collectors to effectively incorporate novel cathode nanoparticles towards high energy lithium ion batteries. The use of CNT additives with commercial high capacity lithium rich cathodes was shown to increase areal loadings and specific capacity compared to using carbon black additives. Synthesis of alternative lithium rich cathode active materials exhibited room temperature capacity of 170 mAh/g, and a high temperature capacity of 240 mAh/g. Modeling results indicate that the use of these particles coated onto CNT current collectors can result in battery energy density increases up to 15% (vs. mesocarbon microbead (MCMB)).

关键词：能量密度；轻量级；锂电池

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This thesis forms part of a larger study that aims to develop a renewable energy demonstration plant at the Naval Postgraduate School Turbopropulsion Laboratory. The architecture and design approach of the demonstration plant is outlined in this thesis. While all the components of the system are commercially available, the integration of the components is challenging. The results of the design approach presented the optimal way of integrating wind turbines, an electrical system, chiller units, and thermal storage tanks. Modular ice thermal tanks with polypropylene tubing were chosen for storage. The ice thermal storage units were selected over battery storage as they are more cost effective and potentially safer. A statistical analysis was performed using wind data from Monterey Airport, which was beneficial for choosing which wind turbines to implement in the system. The analysis determined that total energy captured by two, 4-kW vertical axis wind turbines was 2,554.8 kW-hours annually. Additionally, ANSYS Fluent was used to analyze the ice growth around the tubing at various ice and tube thicknesses. The ANSYS Fluent analysis showed that ice thickness affects the ice volume growth and change in enthalpy change more than wall thickness affects these conditions.

关键词：能源存储；热性能；冷却；电气设备

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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：电气性能；实地测试；低功耗；信号处理

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This research project sought to develop a prototype hydrogen-based fuel cell system for ITS devices. The project investigated hydrogen storage capacities of the various candidate chemical hydride analogs; selected the most efficient of the candidates for energy storage based on volume, mass, and cost; developed a prototype system; and estimated the capital and operating cost for such a system. A hydrogen fuel cell combines hydrogen and oxygen to produce electricity, providing a clean, high-efficiency energy source that circumvents the problems associated with conventional batteries. A major drawback that limits its utility, however, is the use of heavy and bulky compressed metal cylinders as the source of hydrogen. The chemical-based hydrogen generation used in this project can provide a compact, atmospheric-pressure storage option for the controlled release of hydrogen. Many ITS-based applications can be envisaged with hydrogen-based fuel cells, such as alternating-traffic signs, directional signals, speed-limit signs, blinkers in series, warning blinkers, and backup power sources at traffic signals during power outages. This system is particularly attractive because many remote traffic signals on northern Minnesota roads lack access to a power grid, requiring the use of batteries that must be changed often, thus incurring maintenance costs.

关键词：电动电池；燃料电池；智能交通系统(ITS)

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The catenating property of carbon makes it unique to forming various architectures (e.g. diamond, fullerenes, carbon nanotubes, graphene, etc.) at nanolevel. Graphene, a 2D material, has received increasing attention since the first historical isolation of single-layer graphene from the crystalline graphite in 2004 owing to its unique physicochemical properties and ease of functionalization. Suitable methods have been discovered to synthesize graphene and its composites with metal/oxide nanoparticles for use in electrochemical devices to improve their efficiencies. This chapter with a brief description of methods of synthesis of graphene and its structural characterization presents a detailed review of the work carried out on application of graphene to improve the performance of electrochemical devices, namely fuel cells, supercapacitors and batteries.

关键词：电池；电化学设备；石墨烯；超级电容器

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Electronic transformer Manager nature is a will simulation volume transformation for digital volume of device, they will simulation of current and the voltage signal in as possible near signal source of local used most has price of reliable way will its transformation for digital volume,electronic type transformer Manager and merged unit as digital substation of component, and traditional transformer Manager compared to has insulated simple, and dynamic range wide, and anti-saturated performance strong, and Advantages of data output.combined digital substation with IEC61850 in the text, examined issues such as data synchronization of electronic instrument transformers, made recommendations on engineering practice.

关键词：电子变压器；数字化变电站；数据同步；合并单元格

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Many sources of fuel are present aboard current spacecraft, with one especially hazardous source of stored energy: lithium ion batteries. Lithium ion batteries are a very hazardous form of fuel due to their self-sustaining combustion once ignited, for example, by an external heat source. Batteries can become extremely energetic fire sources due to their high density electrochemical energy content that may, under duress, be violently converted to thermal energy and fire in the form of a thermal runaway. Currently, lithium ion batteries are the preferred types of batteries aboard international spacecraft and therefore are routinely installed, collectively forming a potentially devastating fire threat to a spacecraft and its crew. Currently NASA is developing a fine water mist portable fire extinguisher for future use on international spacecraft. As its development ensues, a need for the standard evaluation of various types of fire extinguishers against this potential threat is required to provide an unbiased means of comparing between fire extinguisher technologies and ranking them based on performance.

关键词：锂离子电池；能量存储；手提灭火器

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A thermal energy storage system capable of receiving, absorbing, and collecting solar energy, and storing it within a phase change material, has been designed as part of a power and propulsion system for use in low Earth orbit. The design includes thermophotovoltaic cells for the conversion of stored heat to electrical energy for various satellite systems, as well as a heat exchanger imbedded in the phase change material for propellant heating during thrust maneuvers. Through computational analysis, the likely thrust was evaluated as well as the impact of the propellant flow on the thermal to electric conversion. For the scenario analyzed, a propellant exit temperature of 1500 K, translating to an Isp of 300 seconds, was achieved. Passing the propellant through the phase change material decreases the temperature of the emitter used to power the thermophotovoltaics and resulted in a 20% decrease in electric power output.

关键词：人工卫星；冷气体；地球轨道；电力；储能

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