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DOE OSTI2012

Service Oriented Architecture for High Level Applications

Standalone high level applications often suffer from poor performance and reliability due to lengthy initialization, heavy computation and rapid graphical update. Service-oriented architecture (SOA) is trying to separate the initialization and computation from applications and to distribute such work to various service providers. Heavy computation such as beam tracking will be done periodically on a dedicated server and data will be available to client applications at all time. Industrial standard service architecture can help to improve the performance, reliability and maintainability of the service. Robustness will also be improved by reducing the complexity of individual client applications.

43 PARTICLE ACCELERATORS↗

DOE OSTI2012

Scheduling applications for execution on a plurality of compute nodes of a parallel computer to manage temperature of the nodes during execution

Methods, apparatus, and products are disclosed for scheduling applications for execution on a plurality of compute nodes of a parallel computer to manage temperature of the plurality of compute nodes during execution that include: identifying one or more applications for execution on the plurality of compute nodes; creating a plurality of physically discontiguous node partitions in dependence upon temperature characteristics for the compute nodes and a physical topology for the compute nodes, each discontiguous node partition specifying a collection of physically adjacent compute nodes; and assigning, for each application, that application to one or more of the discontiguous node partitions for execution on the compute nodes specified by the assigned discontiguous node partitions.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2013

Performance implications from sizing a VM on multi-core systems: A Data analytic application s view

In this paper, we present a quantitative performance analysis of data analytics applications running on multi-core virtual machines. Such environments form the core of cloud computing. In addition, data analytics applications, such as Cassandra and Hadoop, are becoming increasingly popular on cloud computing platforms. This convergence necessitates a better understanding of the performance and cost implications of such hybrid systems. For example, the very rst step in hosting applications in virtualized environments, requires the user to con gure the number of virtual processors and the size of memory. To understand performance implications of this step, we benchmarked three Yahoo Cloud Serving Benchmark (YCSB) workloads in a virtualized multi-core environment. Our measurements indicate that the performance of Cassandra for YCSB workloads does not heavily depend on the processing capacity of a system, while the size of the data set is critical to performance relative to allocated memory. We also identi ed a strong relationship between the running time of workloads and various hardware events (last level cache loads, misses, and CPU migrations). From this analysis, we provide several suggestions to improve the performance of data analytics applications running on cloud computing environments.

Lim, Seung-Hwan↗

DOE OSTI2013

Toward Abstracting the Communication Intent in Applications to Improve Portability and Productivity

Programming with communication libraries such as the Message Passing Interface (MPI) obscures the high-level intent of the communication in an application and makes static communication analysis difficult to do. Compilers are unaware of communication libraries specifics, leading to the exclusion of communication patterns from any automated analysis and optimizations. To overcome this, communication patterns can be expressed at higher-levels of abstraction and incrementally added to existing MPI applications. In this paper, we propose the use of directives to clearly express the communication intent of an application in a way that is not specific to a given communication library. Our communication directives allow programmers to express communication among processes in a portable way, giving hints to the compiler on regions of computations that can be overlapped with communication and relaxing communication constraints on the ordering, completion and synchronization of the communication imposed by specific libraries such as MPI. The directives can then be translated by the compiler into message passing calls that efficiently implement the intended pattern and be targeted to multiple communication libraries. Thus far, we have used the directives to express point-to-point communication patterns in C, C++ and Fortran applications, and have translated them to MPI and SHMEM.

Mintz, Tiffany M↗

DOE OSTI2013

Applications of High Resolution Laser Induced Breakdown Spectroscopy for Environmental and Biological Samples

This chapter details the application of LIBS in a number of environmental areas of research such as carbon sequestration and climate change. LIBS has also been shown to be useful in other high resolution environmental applications for example, elemental mapping and detection of metals in plant materials. LIBS has also been used in phytoremediation applications. Other biological research involves a detailed understanding of wood chemistry response to precipitation variations and also to forest fires. A cross-section of Mountain pine (pinceae Pinus pungen Lamb.) was scanned using a translational stage to determine the differences in the chemical features both before and after a fire event. Consequently, by monitoring the elemental composition pattern of a tree and by looking for abrupt changes, one can reconstruct the disturbance history of a tree and a forest. Lastly we have shown that multivariate analysis of the LIBS data is necessary to standardize the analysis and correlate to other standard laboratory techniques. LIBS along with multivariate statistical analysis makes it a very powerful technology that can be transferred from laboratory to field applications with ease.

Martin, Madhavi Z↗

DOE OSTI2013

SCORPIO: A Scalable Two-Phase Parallel I/O Library With Application To A Large Scale Subsurface Simulator

Inefficient parallel I/O is known to be a major bottleneck among scientific applications employed on supercomputers as the number of processor cores grows into the thousands. Our prior experience indicated that parallel I/O libraries such as HDF5 that rely on MPI-IO do not scale well beyond 10K processor cores, especially on parallel file systems (like Lustre) with single point of resource contention. Our previous optimization efforts for a massively parallel multi-phase and multi-component subsurface simulator (PFLOTRAN) led to a two-phase I/O approach at the application level where a set of designated processes participate in the I/O process by splitting the I/O operation into a communication phase and a disk I/O phase. The designated I/O processes are created by splitting the MPI global communicator into multiple sub-communicators. The root process in each sub-communicator is responsible for performing the I/O operations for the entire group and then distributing the data to rest of the group. This approach resulted in over 25X speedup in HDF I/O read performance and 3X speedup in write performance for PFLOTRAN at over 100K processor cores on the ORNL Jaguar supercomputer. This research describes the design and development of a general purpose parallel I/O library, SCORPIO (SCalable block-ORiented Parallel I/O) that incorporates our optimized two-phase I/O approach. The library provides a simplified higher level abstraction to the user, sitting atop existing parallel I/O libraries (such as HDF5) and implements optimized I/O access patterns that can scale on larger number of processors. Performance results with standard benchmark problems and PFLOTRAN indicate that our library is able to maintain the same speedups as before with the added flexibility of being applicable to a wider range of I/O intensive applications.

High Performance Computing↗

DOE OSTI2014

Application Power Signature Analysis

The high-performance computing (HPC) community has been greatly concerned about energy efficiency. To address this concern, it is essential to understand and characterize the electrical loads of HPC applications. In this work, we study whether HPC applications can be distinguished by their power-consumption patterns using quantitative measures in an automatic manner. Using a collection of 88 power traces from 4 different systems, we find that basic statistical measures do a surprisingly good job of summarizing applications' distinctive power behavior. Moreover, this study opens up a new area of research in power-aware HPC that has a multitude of potential applications.

Hsu, Chung-Hsing↗

DOE OSTI2013

The IAEA Workshop on Requirements and Potential Technologies for Replacement of 3He Detectors in IAEA Safeguards Applications

From 22 – 24 March, 2011, the International Atomic Energy Agency (IAEA) held an international workshop to address the question of a possible replacement for helium-3 based neutron detectors. Within this wider scope, the workshop was focused on those applications used in IAEA verification activities. There were two principle objectives of the workshop: 1) to determine the specific requirements that a potential replacement technology would have to satisfy, and 2) to identify alternative detector technologies that appear promising for meeting those requirements. The workshop was successful in achieving both objectives. A set of detailed and quantitative specifications was developed and achieved a general consensus among the conference participants. These included operational considerations such as temperature stability, safety, weight, and cost in addition to a number of performance requirements. The performance requirements were derived from an analysis of the spectrum of IAEA applications that use neutron detectors. After analyzing these applications, it was determined that the most common application for 3He detectors was for neutron coincidence counting, comprising over 95% of 3He use. The details and rationale for this assessment will be provided. The performance requirements for neutron coincidence counting can be directly calculated from the standard variance expressions. From these, a basic figure of merit (FOM) was developed that can be used to rank various different options. For neutron coincidence counting, the figure of merit is: , where ε is the detection efficiency and is the detector die away time. Both the FOM and the calculations will be presented. The full list of requirements is included in this paper. The second purpose of the workshop was to identify promising replacement technologies. There were multiple presentations of candidate detection technologies over the course of the workshop, covering a wide spectrum of approaches and detection physics. These technologies were judged relative to the performance of a 3He-based system, as well as its ability to meet the replacement technology requirements as developed in this workshop. The paper will present a summary of this assessment.

Pickrell, Mark↗

DOE OSTI2014

EXTENDING NUCLEAR ENERGY TO NON-ELECTRICAL APPLICATIONS

Electricity represents less than half of all energy consumed in the United States and globally. Although a few commercial nuclear power plants world-wide provide energy to non-electrical applications such as district heating and water desalination, nuclear energy has been largely relegated to base-load electricity production. A new generation of smaller-sized nuclear power plants offers significant promise for extending nuclear energy to many non-electrical applications. The NuScale small modular reactor design is especially well suited for these non-traditional customers due to its small unit size, very robust reactor protection features and a highly flexible and scalable plant design. A series of technical and economic evaluation studies have been conducted to assess the practicality of using a NuScale plant to provide electricity and heat to a variety of non-electrical applications, including water desalination, oil refining, and hydrogen production. The studies serve to highlight the unique design features of the NuScale plant for these applications and provide encouraging conclusions regarding the technical and economic viability of extending clean nuclear energy to a broad range of non-electrical energy consumers.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2014

Rydberg Excitation of Single Atoms for Applications in Quantum Information and Metrology

With the advent of laser cooling and trapping, neutral atoms have become a foundational source of accuracy for applications in metrology and are showing great potential for their use as qubits in quantum information. In metrology, neutral atoms provide the most accurate references for the measurement of time and acceleration. The unsurpassed stability provided by these systems make neutral atoms an attractive avenue to explore applications in quantum information and computing. However, to fully investigate the eld of quantum information, we require a method to generate entangling interactions between neutral-atom qubits. Recent progress in the use of highly-excited Rydberg states for strong dipolar interactions has shown great promise for controlled entanglement using the Rydberg blockade phenomenon. I report the use of singly-trapped 133 Cs atoms as qubits for applications in metrology and quantum information. Each atom provides a physical basis for a single qubit by encoding the required information into the ground-state hyper ne structure of 133 Cs. Through the manipulation of these qubits with microwave and optical frequency sources, we demonstrate the capacity for arbitrary single-qubit control by driving qubit rotations in three orthogonal directions on the Bloch sphere. With this control, we develop an atom interferometer that far surpasses the force sensitivity of other approaches by applying the well-established technique of lightpulsed atom-matterwave interferometry to single atoms. Following this, we focus on two-qubit interactions using highly-excited Rydberg states. Through the development of a unique single-photon approach to Rydberg excitation using an ultraviolet laser at 319 nm, we observe the Rydberg blockade interaction between atoms separated by 6.6(3) m. Motivated by the observation of Rydberg blockade, we study the application of Rydberg-dressed states for a quantum controlled-phase gate. Using a realistic simulation of the dressed-state dynamics, we calculate a controlled-phase gate delity of 94% that is primarily limited by Doppler frequency shifts. Finally, we employ our single-photon excitation laser to measure the Rydberg-dressed interaction, thus demonstrating the viability of this approach.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2014

Redwing: A MOOSE application for coupling MPACT and BISON

Fuel performance and whole core neutron transport programs are often used to analyze fuel behavior as it is depleted in a reactor. For fuel performance programs, internal models provide the local intra-pin power density, fast neutron flux, burnup, and fission rate density, which are needed for a fuel performance analysis. The fuel performance internal models have a number of limitations. These include effects on the intra-pin power distribution by nearby assembly elements, such as water channels and control rods, and the further limitation of applicability to a specified fuel type such as low enriched UO2. In addition, whole core neutron transport codes need an accurate intra-pin temperature distribution in order to calculate neutron cross sections. Fuel performance simulations are able to model the intra-pin fuel displacement as the fuel expands and densifies. These displacements must be accurately modeled in order to capture the eventual mechanical contact of the fuel and the clad; the correct radial gap width is needed for an accurate calculation of the temperature distribution of the fuel rod. Redwing is a MOOSE-based application that enables coupling between MPACT and BISON for transport and fuel performance coupling. MPACT is a 3D neutron transport and reactor core simulator based on the method of characteristics (MOC). The development of MPACT began at the University of Michigan (UM) and now is under the joint development of ORNL and UM as part of the DOE CASL Simulation Hub. MPACT is able to model the effects of local assembly elements and is able calculate intra-pin quantities such as the local power density on a volumetric mesh for any fuel type. BISON is a fuel performance application of Multi-physics Object Oriented Simulation Environment (MOOSE), which is under development at Idaho National Laboratory. BISON is able to solve the nonlinearly coupled mechanical deformation and heat transfer finite element equations that model a fuel element as it is depleted in a nuclear reactor. Redwing couples BISON and MPACT in a single application. Redwing maps and transfers the individual intra-pin quantities such as fission rate density, power density, and fast neutron flux from the MPACT volumetric mesh to the individual BISON finite element meshes. For a two-way coupling Redwing maps and transfers the individual pin temperature field and axially dependent coolant densities from the BISON mesh to the MPACT volumetric mesh. Details of the mapping are given. Redwing advances the simulation with the MPACT solution for each depletion time step and then advances the multiple BISON simulations for fuel performance calculations. Sub-cycle advancement can be applied to the individual BISON simulations and allows multiple time steps to be applied to the fuel performance simulations. Currently, only loose coupling where data from a previous time step is applied to the current time step is performed.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2015

Aggregating job exit statuses of a plurality of compute nodes executing a parallel application

Aggregating job exit statuses of a plurality of compute nodes executing a parallel application, including: identifying a subset of compute nodes in the parallel computer to execute the parallel application; selecting one compute node in the subset of compute nodes in the parallel computer as a job leader compute node; initiating execution of the parallel application on the subset of compute nodes; receiving an exit status from each compute node in the subset of compute nodes, where the exit status for each compute node includes information describing execution of some portion of the parallel application by the compute node; aggregating each exit status from each compute node in the subset of compute nodes; and sending an aggregated exit status for the subset of compute nodes in the parallel computer.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2015

RCRA Part B Permit Application Nevada National Security Site (NNSS) for Waste Management Activities at the NNSS Mixed Waste Storage Unit (MWSU)

This volume of the Resource Conservation and Recovery Act (RCRA) permit application to the Nevada Division of Environmental Protection focuses on continued operation of the Mixed Waste Storage Unit at the Nevada National Security Site (NNSS), under the auspices of DOE’s National Nuclear Security Administration Nevada Field Office (NNSA/NFO). Low-level mixed waste (LLMW) accepted at the NNSS contains both radioactive and hazardous material components as defined by various laws and regulations. The Mixed Waste Storage Unit (MWSU) is located at the Area 5 Radioactive Waste Management Complex (RWMC). Existing facilities at the RWMC are used to store LLMW generated at or shipped to the NNSS prior to disposal at the Mixed Waste Disposal Unit (MWDU). The document describes the MWSU, its general design, its operation, the materials it stores, and relevant health and safety regulations with which NNSS complies. The currently permitted MWSU has been operated since December 2010. Each of the four designated storage areas is RCRA-compliant for the storage of hazardous waste. This application represents a renewal request by DOE for the permitted MWSU. For security reasons, some of the contents of the full application are not available for public viewing. This version of the application contains most but not all of the contents as submitted to the regulatory agencies.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2018

MUFFSgenMC: An Open Source Muon Flexible Framework for Spectral Generation for Monte Carlo Applications

A cosmic ray Muon Flexible Framework for Spectral Generation for Monte Carlo Applications (MUFFSgenMC) has been developed to support state-of-the-art cosmic ray muon detection and tomographic applications. The flexible framework allows for easy and fast creation of source terms for popular Monte Carlo applications such as GEANT4 and MCNP, which simplifies the process of simulations. The flexible framework contains a variety of analytical, numerical, and parametric models that capture the main characteristics of the muon energy and angular distributions in the range 0 to 90 and at arbitrary energies. The primary model for muon energy distribution is an implementation of the Smith and Duller phenomenological model. The predictions for muon energies in the range from 1 GeV to 1 TeV and zenith angles 0 to 90 are validated against an extensive series of experimental spectrum measurements. Finally, the open source code available on Matlab’s Mathworks File Exchange (https://www.mathworks.com/matlabcentral/fileexchange/65585-muffsgenmc) was written to allow users to easily modify and expand the code. MUFFSgenMC can facilitate the study of cosmic ray muons for nuclear nonproliferation applications and will enable the development of new muon-based detection and imaging techniques by providing an easy source term generator.

Greulich, Christopher↗

DOE OSTI2019

Application-based QoE support with P4 and OpenFlow

Although Software-Defined Wide Area Networks (SD-WANs) are now widely deployed in several production networks, they are largely restricted to traffic engineering approaches based on layer 4 (L4) of the network protocol stack that result in improved Quality-of-Service (QoS) of the network overall without necessarily focusing on a specific application. However, the emergence of application protocols such as QUIC and HTTP/2 needs an investigation of layer 5-based (L5) approaches in order to improve users’ Quality-of-Experience (QoE). In this paper, we leverage the capabilities of flexible, P4-based switches that incorporate protocol-independent packet processing in order to intelligently route traffic based on application headers. We use Adaptive Bit Rate (ABR) video streaming as an example to show how such an approach can not only provide flexible traffic management but also improve application QoE. Our evaluation consists of an actual deployment in a research testbed, Chameleon, where we leverage the benefits of fast paths in order to retransmit video segments in higher qualities. Further, we analyze real-world ABR streaming sessions from a large-scale CDN and show that our approach can successfully maximize QoE for all users in the dataset.

Bhat, Divyashri↗

DOE OSTI2019

Low Field Nondestructive Evaluation Methods and Applications

Several types of low-field magnetic sensors have been presented for a wide range of NDE applications, each of them having their own advantages over the others. On the one hand, SQUID sensors are capable of measuring very low magnetic field and hence are well suited for biomagnetic applications. However, due to the requirement of a cooling environment, these sensors can be expensive especially if a coolant other than liquid nitrogen is required to initiate superconductivity in the materials. On the other hand, flux gate sensors, which are less expensive than SQUIDs are used in military applications requiring small magnetic field measurements. MR sensors and Hall sensors are developed to measure fields of medium and high strength, respectively. Induction sensors have the widest range compared to any other sensor and can be tailored towards any application, with obvious limitations on the sensitivity and dimensions requirements of the sensors. The GMR sensors are most promising in terms of sensitivity and cost. The TMR sensors are in the stage of development and efforts are needed to overcome the handling abilities by improving the tolerance to higher voltage levels without shorting.

20 FOSSIL-FUELED POWER PLANTS↗

DOE OSTI2019

Initial Application of TSUNAMI for Validation of Advanced Fuel Systems

A number of advanced reactor concepts and accident-tolerant fuels (ATFs) are under development or in the initial stages of deployment and testing in the nuclear power industry. Many of these concepts incorporate chemical or material forms that have not traditionally been used in the nuclear industry and may present challenges for nuclear criticality safety validation. Sensitivity/uncertainty methods are ideally suited for assessing the applicability of existing critical experiments to these potentially challenging applications. This paper presents two case studies recently completed at Oak Ridge National Laboratory (ORNL) which investigated the use of the TSUNAMI tools within the SCALE code system to perform such assessments.Many advanced reactor concepts include uranium enrichments above 5 wt% 235U but below the 20 wt% limit of low-enriched uranium (LEU). This material, referred to as high assay LEU (HA-LEU), poses difficulties across the entire infrastructure of nuclear power, including enrichment, transportation, fabrication, and storage. A potentially representative transportation package was selected to perform a criticality safety validation assessment for UF6 containing HA-LEU. Sensitivity data were generated using the TSUNAMI-3D sequence, and an assessment of the applicability of a range of critical experiments was performed using the TSUNAMI-IP tool. The critical experiments were drawn from the set of available sensitivity data files distributed with the International Criticality Safety Benchmark Evaluation Project (ICSBEP) Handbook. The results indicate that a sufficient number of available experiments may be available to perform validations for these systems.Many different cladding materials and fuel dopants are included in ATFs to mitigate the consequences of a loss of coolant accident. Some of these systems have already been fabricated and introduced as lead test assemblies in commercial reactors, while others are still being developed. Several concepts were considered for pressurized-water reactors (PWRs) and boiling-water reactors (BWRs) in comparison to the current Zircaloy and UO2 fuel system. In most of these cases, the ATF materials did not significantly impact the number of applicable experiments for validation. Some fuel and cladding materials were identified, however, which may reduce the number of available experiments and which will increase the nuclear data–induced uncertainty in neutron multiplication.

Marshall, William (B.J.)↗

DOE OSTI2020

Study of Additive Manufacturing Application to Geothermal Technologies

Geothermal reservoir characterization, field construction, and reservoir operations are very technology intensive activities that contribute significantly to the cost of delivering electricity produced from geothermal resources. Many geothermal technologies, such as downhole tools and drilling equipment, have unusual material, design, and manufacturing considerations dictated by the harsh geothermal environment and extreme aspect ratios required for deployment in a borehole. An additional challenge that faces geothermal applications is the low tool production volume needed to support the industry. Whereas tens of thousands of Oil & Gas wells are drilled and completed in the U.S. annually, there are typically only tens of geothermal wells that are drilled and completed. If a tool typically used in Oil & Gas applications cannot be directly used for geothermal, then the cost associated with making the tool suitable for geothermal is often prohibitive. There is therefore a much smaller inventory of technologies available to geothermal as compared to Oil & Gas and the level of efficiency and sophistication associated with field practice suffers accordingly. A number of advanced manufacturing methods, such as additive manufacturing, have received increased R&D as well as commercial attention in recent years because of their ability to rapidly prototype complex parts. Additive manufacturing in particular provides an opportunity to increase the technology available to the geothermal industry by either reducing fabrication costs associated with complex components or enabling economic production of low volume parts where specialized tooling is often required. Additional potential benefits of additive manufacturing include increased design freedom to make higher performing parts that cannot be made conventionally, the ability to integrate components into assemblies without joining operations, and the ability to economically fabricate variations on design in cases, such as casting molds, where there are large up-front costs associated with tooling. We have recently completed a study that investigated technology needs, representative use cases, manufacturability, and a techno-economic framework for comparing conventional to additive manufacturing methods for geothermal applications. This paper will provide an overview of this recent effort, describe the different elements of the assessment, and summarize the key takeaways related to both the feasibility of using additive manufacturing for geothermal technology applications as well as the potential benefits and impacts.

Polsky, Yarom↗