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At least 991 records · Page 55

The Modern Research Data Portal: A Design Pattern for Networked, Data-Intensive Science

Here we describe best practices for providing convenient, high-speed, secure access to large data via research data portals. We capture these best practices in a new design pattern, the Modern Research Data Portal, that disaggregates the traditional monolithic web-based data portal to achieve orders-of-magnitude increases in data transfer performance, support new deployment architectures that decouple control logic from data storage, and reduce development and operations costs. We introduce the design pattern; explain how it leverages high-performance Science DMZs and cloud-based data management services; review representative examples at research laboratories and universities, including both experimental facilities and supercomputer sites; describe how to leverage Python APIs for authentication, authorization, data transfer, and data sharing; and use coding examples to demonstrate how these APIs can be used to implement a range of research data portal capabilities. Sample code at a companion web site, https://docs.globus.org/mrdp, provides application skeletons that readers can adapt to realize their own research data portals.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗

The Modern Research Data Portal: a design pattern for networked, data-intensive science

We describe best practices for providing convenient, high-speed, secure access to large data via research data portals. Here, we capture these best practices in a new design pattern, the Modern Research Data Portal, that disaggregates the traditional monolithic web-based data portal to achieve orders-of-magnitude increases in data transfer performance, support new deployment architectures that decouple control logic from data storage, and reduce development and operations costs. We introduce the design pattern; explain how it leverages high-performance data enclaves and cloud-based data management services; review representative examples at research laboratories and universities, including both experimental facilities and supercomputer sites; describe how to leverage Python APIs for authentication, authorization, data transfer, and data sharing; and use coding examples to demonstrate how these APIs can be used to implement a range of research data portal capabilities. Sample code at a companion web site, https://docs.globus.org/mrdp , provides application skeletons that readers can adapt to realize their own research data portals.

97 MATHEMATICS AND COMPUTING↗

Simulating Microbial Community Patterning Using Biocellion

Mathematical modeling and computer simulation are important tools for understanding complex interactions between cells and their biotic and abiotic environment: similarities and differences between modeled and observed behavior provide the basis for hypothesis forma- tion. Momeni et al. [5] investigated pattern formation in communities of yeast strains engaging in different types of ecological interactions, comparing the predictions of mathematical modeling and simulation to actual patterns observed in wet-lab experiments. However, simu- lations of millions of cells in a three-dimensional community are ex- tremely time-consuming. One simulation run in MATLAB may take a week or longer, inhibiting exploration of the vast space of parameter combinations and assumptions. Improving the speed, scale, and accu- racy of such simulations facilitates hypothesis formation and expedites discovery. Biocellion is a high performance software framework for ac- celerating discrete agent-based simulation of biological systems with millions to trillions of cells. Simulations of comparable scale and accu- racy to those taking a week of computer time using MATLAB require just hours using Biocellion on a multicore workstation. Biocellion fur- ther accelerates large scale, high resolution simulations using cluster computers by partitioning the work to run on multiple compute nodes. Biocellion targets computational biologists who have mathematical modeling backgrounds and basic C++ programming skills. This chap- ter describes the necessary steps to adapt the original Momeni et al.'s model to the Biocellion framework as a case study.

metabolic interaction↗

Glass strengthening and patterning methods

High intensity plasma-arc heat sources, such as a plasma-arc lamp, are used to irradiate glass, glass ceramics and/or ceramic materials to strengthen the glass. The same high intensity plasma-arc heat source may also be used to form a permanent pattern on the glass surface--the pattern being raised above the glass surface and integral with the glass (formed of the same material) by use of, for example, a screen-printed ink composition having been irradiated by the heat source.

36 MATERIALS SCIENCE↗

Self-assembly of block copolymers on topographically patterned polymeric substrates

Highly-ordered block copolymer films are prepared by a method that includes forming a polymeric replica of a topographically patterned crystalline surface, forming a block copolymer film on the topographically patterned surface of the polymeric replica, and annealing the block copolymer film. The resulting structures can be used in a variety of different applications, including the fabrication of high density data storage media. The ability to use flexible polymers to form the polymeric replica facilitates industrial-scale processes utilizing the highly-ordered block copolymer films.

36 MATERIALS SCIENCE↗

Baselining PMU Data to Find Patterns and Anomalies

This paper looks at the application of situational awareness methodologies with respect to power grid data. These methodologies establish baselines that look for typical patterns and atypical behavior in the data. The objectives of the baselining analyses are to provide: real-time analytics, the capability to look at historical trends and events, and reliable predictions of the near future state of the grid. Multivariate algorithms were created to establish normal baseline behavior and then score each moment in time according to its variance from the baseline. Detailed multivariate analytical techniques are described in this paper that produced ways to identify typical patterns and atypical behavior. In this case, atypical behavior is behavior that is unenvisioned. Visualizations were also produced to help explain the behavior that was identified mathematically. Examples are shown to help describe how to read and interpret the analyses and visualizations. Preliminary work has been performed on PMU data sets from BPA (Bonneville Power Administration) and EI (Eastern Interconnect). Actual results are not fully shown here because of confidentiality issues. Comparisons between atypical events found mathematically and actual events showed that many of the actual events are also atypical events; however there are many atypical events that do not correlate to any actual events. Additional work needs to be done to help classify the atypical events into actual events, so that the importance of the events can be better understood.

Baselining analyses↗

Three-dimensional patterning methods and related devices

Three-dimensional patterning methods of a three-dimensional microstructure, such as a semiconductor wire array, are described, in conjunction with etching and/or deposition steps to pattern the three-dimensional microstructure.

36 MATERIALS SCIENCE↗

Patterned structures of graphene and graphitic carbon and methods for their manufacture

A patterned graphene or graphitic body is produced by providing a three-dimensionally patterned carbonaceous body; coating the body with a catalytic metal whereby is formed a coating having an inner surface proximal the body and an outer surface distal the body; and annealing the coated body under time and temperature conditions effective to form a graphene or graphitic layer on the outer surface of the catalytic metal coating.

36 MATERIALS SCIENCE↗

An Integrated Design Approach for Infill Patterning of Fused Deposition Modeling and its Application to an Airfoil

We present a new approach to incorporate an internal stress distribution into the design of infill via fused deposition modeling of additive manufacturing (AM). This design approach differs from topology optimization, since the topology optimization of AM focuses on changing the overall shape of the product, whereas the approach we propose in this research focuses on the porous infill and remains the overall shape of the product intact. The approach presented here is effective if the overall shape is an important functioning aspect of a product and the stress is applied to the entire body, not to given localized points. As an application, we demonstrate an airfoil with its infill densities optimized based on the pressure applied during operation. Specifically, the stress of an airfoil is analyzed with operational loading conditions. The local density of the infill pattern is determined based on the computational stress analysis. The infill geometry is mathematically generated using a circle packing algorithm. Test results show that the airfoil with the optimized infill outperforms the same shape with the traditional uniform infill pattern of an airfoil having the same weight.

Kim, Pum↗

Patterned structures of graphene and graphitic carbon and methods for their manufacture

A patterned graphene or graphitic body is produced by providing a three-dimensionally patterned carbonaceous body; coating the body with a catalytic metal whereby is formed a coating having an inner surface proximal the body and an outer surface distal the body; and annealing the coated body under time and temperature conditions effective to form a graphene or graphitic layer on the outer surface of the catalytic metal coating.

36 MATERIALS SCIENCE↗

Text and Graph Based Approach for Analyzing Patterns of Research Collaboration: An Analysis of the TrueImpactDataset

Patterns of scientific collaboration and their effect on scientific production have been the subject of many studies. In this paper, we analyze the nature of ties between co-authors and study collaboration patterns in science from the perspective of semantic similarity of authors who wrote a paper together and the strength of ties between these authors (i.e. how frequently have they previously collaborated together). These two views of scientific collaboration are used to analyze publications in the TrueImpactDataset (Herrmannova et al., 2017) (Herrmannova et al., 2017), a new dataset containing two types of publications – publications regarded as seminal and publications regarded as literature reviews by field experts. We show there are distinct differences between seminal publications and literature reviews in terms of author similarity and the strength of ties between their authors. In particular, we find that seminal publications tend to be written by authors who have previously worked on dissimilar problems (i.e. authors from different fields or even disciplines), and by authors who are not frequent collaborators. On the other hand, literature reviews in our dataset tend to be the result of an established collaboration within a discipline. This demonstrates that our method provides meaningful information about potential future impacts of a publication which does not require citation information.

Herrmannova, Dasha↗

Electron Beam Pattern Rotation as a Method of Tunable Bunch Train Generation

Transversely modulated electron beams can be formed in photo injectors via microlens array (MLA) UV laser shap- ing technique. Microlenses can be arranged in polygonal lattices, with resulting transverse electron beam modula- tion mimicking the lenses pattern. Conventionally, square MLAs are used for UV laser beam shaping, and generated electron beam patterns form square beamlet arrays. The MLA setup can be placed on a rotational mount, thereby rotating electron beam distribution. In combination with transverse-to-longitudinal emittance exchange (EEX) beam line, it allows to vary beamlets horizontal projection and tune electron bunch train. In this paper, we extend the technique to the case of different MLA lattice arrangements and explore the benefits of its rotational symmetries.

43 PARTICLE ACCELERATORS↗

Patterning devices using fluorinated compounds

A method for producing a spatially patterned structure includes forming a layer of a material on at least a portion of a substructure of the spatially patterned structure, forming a barrier layer of a flourinated material on the layer of material to provide an intermediate structure, and exposing the intermediate structure to at least one of a second material or radiation to cause at least one of a chemical change or a structural change to at least a portion of the intermediate structure. The barrier layer substantially protects the layer of the material from chemical and structural changes during the exposing. Substructures are produced according to this method.

Katz, Howard E.↗

Method for producing spatially patterned structures using fluorinated compounds

A method for producing a spatially patterned structure includes forming a layer of a material on at least a portion of a substructure of the spatially patterned structure, forming a barrier layer of a fluorinated material on the layer of material to provide an intermediate structure, and exposing the intermediate structure to at least one of a second material or radiation to cause at least one of a chemical change or a structural change to at least a portion of the intermediate structure. The barrier layer substantially protects the layer of the material from chemical and structural changes during the exposing. Substructures are produced according to this method.

Katz, Howard Edan↗

Patterning devices using fluorinated compounds

A method for producing a spatially patterned structure includes forming a layer of a material on at least a portion of a substructure of the spatially patterned structure, forming a barrier layer of a fluorinated material on the layer of material to provide an intermediate structure, and exposing the intermediate structure to at least one of a second material or radiation to cause at least one of a chemical change or a structural change to at least a portion of the intermediate structure. The barrier layer substantially protects the layer of the material from chemical and structural changes during the exposing. Substructures are produced according to this method.

Katz, Howard E.↗

Augmenting C. elegans Microscopic Dataset for Accelerated Pattern Recognition

The detection of cell shape changes in 3D time-lapse images of complex tissues is an important task. However, it is a challenging and tedious task to establish a comprehensive dataset to improve the performance of deep learning models. In the paper, we present a deep learning approach to augment 3D live images of the Caenorhabditis elegans embryo, so that we can further speed up the specific structure pattern recognition. We use an unsupervised training over unlabeled images to generate supplementary datasets for further pattern recognition. Technically, we used Alex-style neural networks in a generative adversarial network framework to generate new datasets that have common features of the C. elegans membrane structure. We also made the dataset available for a broad scientific community.

Lu, Zheng↗

Selective area growth of semiconductors using patterned sol-gel materials

Systems and methods for growing semiconductor materials on substrates by using patterned sol-gel materials are provided. According to a first aspect of the invention, a method includes forming a pattern of a sol-gel material on a first region of substrate, and depositing a semiconductor material on a second region of the substrate by selective area growth. The second region is adjacent to the first region.

Warren, Emily L.↗

Apparatus and method for visualization of particles suspended in a fluid and fluid flow patterns using ultrasound

An apparatus and method for real-time visualization of particulate matter suspended in a static or flowing fluid and fluid flow patterns in a pipe, tube, conduit, or other container, are described. Ultrasonic scanning and detection of scattered sound from the particles in the fluid create a real-time image of the particles, or of flow patterns in the liquid. A mechanical wobbler directs a piezoelectric transducer over a chosen angle in an oscillatory manner. The transducer is operated in a pulse-echo mode wherein the same transducer detects the return signal from the target region through which particles are passing and/or a flow is present. The pulse-echo measurements are made rapidly and continuously during a single sweep of the transducer over the chosen angle. Received signals are processed in the ultrasound scanner electronics module and displayed as an image in real-time.

42 ENGINEERING↗