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At least 1,513 records · Page 84

Mitigating illumination gradients in a SAR image based on the image data and antenna beam pattern

Illumination gradients in a synthetic aperture radar (SAR) image of a target can be mitigated by determining a correction for pixel values associated with the SAR image. This correction is determined based on information indicative of a beam pattern used by a SAR antenna apparatus to illuminate the target, and also based on the pixel values associated with the SAR image. The correction is applied to the pixel values associated with the SAR image to produce corrected pixel values that define a corrected SAR image.

47 OTHER INSTRUMENTATION↗

Perforation patterned electrical interconnects

This disclosure describes systems and methods for increasing the usable surface area of electrical contacts within a device, such as a thin film solid state device, through the implementation of electrically conductive interconnects. Embodiments described herein include the use of a plurality of electrically conductive interconnects that penetrate through a top contact layer, through one or more multiple layers, and into a bottom contact layer. The plurality of conductive interconnects may form horizontal and vertical cross-sectional patterns. The use of lasers to form the plurality of electrically conductive interconnects from reflowed layer material further aids in the manufacturing process of a device.

42 ENGINEERING↗

Method to manufacture bit patterned magnetic recording media

A method to increase the storage density on magnetic recording media by physically separating the individual bits from each other with a non-magnetic medium (so-called bit patterned media). This allows the bits to be closely packed together without creating magnetic "cross-talk" between adjacent bits. In one embodiment, ferromagnetic particles are submerged in a resin solution, contained in a reservoir. The bottom of the reservoir is made of piezoelectric material.

97 MATHEMATICS AND COMPUTING↗

The Science DMZ: A Network Design Pattern for Data-Intensive Science

The ever-increasing scale of scientific data has become a significant challenge for researchers that rely on networks to interact with remote computing systems and transfer results to collaborators worldwide. Despite the availability of high-capacity connections, scientists struggle with inadequate cyberinfrastructure that cripples data transfer performance, and impedes scientific progress. The Science DMZ paradigm comprises a proven set of network design patterns that collectively address these problems for scientists. We explain the Science DMZ model, including network architecture, system configuration, cybersecurity, and performance tools, that creates an optimized network environment for science. We describe use cases from universities, supercomputing centers and research laboratories, highlighting the effectiveness of the Science DMZ model in diverse operational settings. In all, the Science DMZ model is a solid platform that supports any science workflow, and flexibly accommodates emerging network technologies. As a result, the Science DMZ vastly improves collaboration, accelerating scientific discovery.

42 ENGINEERING↗

Documenting Western Burrowing Owl Reproduction and Activity Patterns Using Motion-Activated Cameras

We used motion-activated cameras to monitor the reproduction and patterns of activity of the Burrowing Owl (Athene cunicularia) above ground at 45 burrows in south-central Nevada during the breeding seasons of 1999, 2000, 2001, and 2005. The 37 broods, encompassing 180 young, raised over the four years represented an average of 4.9 young per successful breeding pair. Young and adult owls were detected at the burrow entrance at all times of the day and night, but adults were detected more frequently during afternoon/early evening than were young. Motion-activated cameras require less effort to implement than other techniques. Limitations include photographing only a small percentage of owl activity at the burrow; not detecting the actual number of eggs, young, or number fledged; and not being able to track individual owls over time. Further work is also necessary to compare the accuracy of productivity estimates generated from motion-activated cameras with other techniques.

54 ENVIRONMENTAL SCIENCES↗

Manipulation of fluids in three-dimensional porous photonic structures with patterned surface properties

A three-dimensional porous photonic structure, whose internal pore surfaces can be provided with desired surface properties in a spatially selective manner with arbitrary patterns, and methods for making the same are described. When exposed to a fluid (e.g., via immersion or wicking), the fluid can selectively penetrate the regions of the structure with compatible surface properties. Broad applications, for example in security, encryption and document authentication, as well as in areas such as simple microfluidics and diagnostics, are anticipated.

36 MATERIALS SCIENCE↗

Customized color patterning of photovoltaic cells

Photovoltaic cells and photovoltaic modules, as well as methods of making and using such photovoltaic cells and photovoltaic modules, are disclosed. More particularly, embodiments of the photovoltaic cells selectively reflect visible light to provide the photovoltaic cells with a colorized appearance. Photovoltaic modules combining colorized photovoltaic cells may be used to harvest solar energy while providing a customized appearance, e.g., an image or pattern.

14 SOLAR ENERGY↗

A Selectivity based approach to Continuous Pattern Detection in Streaming Graphs

Cyber security is one of the most significant technical challenges in current times. Detecting adversarial activities, prevention of theft of intellectual properties and customer data is a high priority for corporations and government agencies around the world. Cyber defenders need to analyze massive-scale, high-resolution network flows to identify, categorize, and mitigate attacks involving networks spanning institutional and national boundaries. Many of the cyber attacks can be described as subgraph patterns, with prominent examples being insider infiltrations (path queries), denial of service (parallel paths) and malicious spreads (tree queries). This motivates us to explore subgraph matching on streaming graphs in a continuous setting. The novelty of our work lies in using the subgraph distributional statistics collected from the streaming graph to determine the query processing strategy. We introduce a ``Lazy Search" algorithm where the search strategy is decided on a vertex-to-vertex basis depending on the likelihood of a match in the vertex neighborhood. We also propose a metric named ``Relative Selectivity" that is used to select between different query processing strategies. Our experiments performed on real online news, network traffic stream and a synthetic social network benchmark demonstrate 10-100x speedups over non-incremental, selectivity agnostic approaches.

dynamic graphs↗

Sequential infiltration synthesis for enhancing multiple-patterning lithography

Simplified methods of multiple-patterning photolithography using sequential infiltration synthesis to modify the photoresist such that it withstands plasma etching better than unmodified resist and replaces one or more hard masks and/or a freezing step in MPL processes including litho-etch-litho-etch photolithography or litho-freeze-litho-etch photolithography.

77 NANOSCIENCE AND NANOTECHNOLOGY↗

Storyline Visualization: A Compelling Way to Understand Patterns over Time and Space

Storyline visualization is a compelling way to understand patterns over time and space. Much effort has been spent developing efficient and aesthetically pleasing layout optimization algorithms. But what if those algorithms are optimizing the wrong things? To answer this question, we conducted a design study with different storyline layout algorithms. We found that users with our new design principles for storyline visualization outperform existing methods.

97 MATHEMATICS AND COMPUTING↗

Manipulation of fluids in three-dimensional porous photonic structures with patterned surface properties

A three-dimensional porous photonic structure, whose internal pore surfaces can be provided with desired surface properties in a spatially selective manner with arbitrary patterns, and methods for making the same are described. When exposed to a fluid (e.g., via immersion or wicking), the fluid can selectively penetrate the regions of the structure with compatible surface properties. Broad applications, for example in security, encryption and document authentication, as well as in areas such as simple microfluidics and diagnostics, are anticipated.

36 MATERIALS SCIENCE↗

Lithographic patterning

This disclosure provides embodiments of an approach that enforces coexistence of multiple, aligned block copolymer morphologies within a single patterning layer.

47 OTHER INSTRUMENTATION↗

Compressed video camera with a moving patterned disk

A high-speed video system is disclosed that includes a moving image absorbing disk at an image plane. The disk has a pattern that passes and blocks image data. The disk is located between an event and an image sensor, or reflects an image to the image sensor. The disk is rotated at a speed that matches the desired reconstructed image frame rate. The image sensor frame data is processed using image reconstruction techniques, such as the D-AMP or TWIST algorithm, to recover a time sequence of reconstructed images. Additional images can be reconstructed for each image sensor frame if some spatial resolution is sacrificed. For continuous video, the disk speed is adjusted to the sensor frame rate. For burst mode, a single sensor image is acquired and a short image sequence is reconstructed. This image capture system works with a variety of radiations, including infrared, light, UV and X-rays.

42 ENGINEERING↗

Method and system for high performance real time pattern recognition

Systems and methods supporting high performance real time pattern recognition by including time and regional multiplexing using high bandwidth, board-to-board communications channels, and 3D vertical integration. An array of processing boards can each be coupled a rear transition board, the array achieving time and regional multiplexing using high bandwidth board-to-board communications channels and 3D vertical integration.

42 ENGINEERING↗

Multi-Frame X-Ray Imaging Using a Streak Camera with a Patterned Photocathode, LAO-008-16, Year 1 of 2

Presentation describes development of a new time-resolved x-ray imaging system based on compressed ultrafast photography (CUP) to achieve multi-frame imaging for energies in the 1–10 keV range with a frame rate between 1 to 10 frames per nanosecond depending on the sweep time. A patterned gold photocathode was constructed for use with an existing Kentech x-ray streak camera. Significant work in reconstruction algorithms was performed to enable reconstructions of data that are much less sparse. These algorithms were tested with optical streak camera CUP data acquired at Livermore Operations.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Pattern generator circuit for high-speed pulse generation

A pattern generator circuit includes a high-speed shift register and a non-overlap generator. The shift register is programmable to produce a pulse train of pulses having a defined pulse duration and a defined pulse-to-pulse interval. The non-overlap generator deserializes the incoming pulse train, and it produces a time-separated reset pulse based on the pulse train. The shift register is configured to permit the pulse durations and pulse-to-pulse interval to be selected arbitrarily over specified ranges in increments of a basic time unit that depends on the oscillator period.

42 ENGINEERING↗

Sequential infiltration synthesis for enhancing multiple-patterning lithography

Simplified methods of multiple-patterning photolithography using sequential infiltration synthesis to modify the photoresist such that it withstands plasma etching better than unmodified resist and replaces one or more hard masks and/or a freezing step in MPL processes including litho-etch-litho-etch photolithography or litho-freeze-litho-etch photolithography.

36 MATERIALS SCIENCE↗