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Aging Assessment of an Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR) Service Cable

Bernstein, Robert; Celina, Mathew C.; Redline, Erica; Von White II, Gregory

Nuclear energy is one industry where aging of safety-related materials and components is of great concern. Many U.S. nuclear power plants are approaching, or have already exceeded, 40 years of age. Analysis comparing the cost of new plant construction versus long-term operation under extended plant licensing through 60 years strongly favors the latter option. To ensure the safe, reliable, and cost-effective long-term operation of nuclear power plants, many systems, structures, and components must be evaluated. Furthermore, as new analytical techniques and testing approaches are developed, it is imperative that we also validate, and if necessary, improve upon the previously employed Institute of Electrical and Electronic Engineers (IEEE) qualification standards originally written in 1974. Fortunately, this daunting task has global support, particularly in light of the new social and political climate surrounding nuclear energy in a post-Fukushima era.

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TYPE Other Report YEAR 2014
DOIOSTI

Dish Stirling High Performance Thermal Storage FY14Q3 Quad Chart

Andraka, Charles E.

The project goals are: demonstrate the feasibility of significant thermal storage for dish Stirling systems to leverage their existing high performance to greater capacity; demonstrate key components of a latent storage and transport system enabling on-dish storage with low exergy losses; and provide technology path to a 25kWe system with 6 hours of storage.

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TYPE Other Report YEAR 2014
DOIOSTI

Thermal boundary conductance accumulation and spectral phonon transmission across interfaces: experimental measurements across metal/native oxide/Si and metal/sapphire interfaces

Nature Communications

Ihlefeld, Jon F.; Brown-Shaklee, Harlan J.; Cheaito, Ramez; Gaskins, John T.; Caplan, Matthew E.; Donovan, Brian F.; Foley, Brian M.; Giri, Ashutosh; Duda, John C.; Szwejkowski, Chester J.; Constantin, Costel; Hopkins, Patrick E.

Abstract not provided.

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TYPE Journal Article YEAR 2014
OSTI

Choreographer Pre-Testing Code Analysis and Operational Testing

Fritz, David J.; Harrison, Christopher B.; Perr, C.W.; Hurd, Steven A.

Choreographer is a "moving target defense system", designed to protect against attacks aimed at IP addresses without corresponding domain name system (DNS) lookups. It coordinates actions between a DNS server and a Network Address Translation (NAT) device to regularly change which publicly available IP addresses' traffic will be routed to the protected device versus routed to a honeypot. More details about how Choreographer operates can be found in Section 2: Introducing Choreographer. Operational considerations for the successful deployment of Choreographer can be found in Section 3. The Testing & Evaluation (T&E) for Choreographer involved 3 phases: Pre-testing, Code Analysis, and Operational Testing. Pre-testing, described in Section 4, involved installing and configuring an instance of Choreographer and verifying it would operate as expected for a simple use case. Our findings were that it was simple and straightforward to prepare a system for a Choreographer installation as well as configure Choreographer to work in a representative environment. Code Analysis, described in Section 5, consisted of running a static code analyzer (HP Fortify) and conducting dynamic analysis tests using the Valgrind instrumentation framework. Choreographer performed well, such that only a few errors that might possibly be problematic in a given operating situation were identified. Operational Testing, described in Section 6, involved operating Choreographer in a representative environment created through EmulyticsTM . Depending upon the amount of server resources dedicated to Choreographer vis-á-vis the amount of client traffic handled, Choreographer had varying degrees of operational success. In an environment with a poorly resourced Choreographer server and as few as 50-100 clients, Choreographer failed to properly route traffic over half the time. Yet, with a well-resourced server, Choreographer handled over 1000 clients without missrouting. Choreographer demonstrated sensitivity to low-latency connections as well as high volumes of traffic. In addition, depending upon the frequency of new connection requests and the size of the address range that Choreographer has to work with, it is possible for all benefits of Choreographer to be ameliorated by its need to allow DNS servers rather than the end client to make DNS requests. Conclusions and Recommendations, listed in Section 7, address the need to understand the specific use case where Choreographer would be deployed to assess whether there would be problems resulting from the operational considerations described in Section 3 or performance concerns from the results of Operational Testing in Section 6. Deployed in an appropriate architecture with sufficiently light traffic volumes and a well-provisioned server, it is quite likely that Choreographer would perform satisfactorily. Thus, we recommend further detailed testing, to potentially include Red Team testing, at such time a specific use case is identified

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TYPE Other Report YEAR 2014
DOIOSTI

Proposing an Abstracted Interface and Protocol for Computer Systems

Resnick, David R.; Ignatowski, Mike

While it made sense for historical reasons to develop different interfaces and protocols for memory channels, CPU to CPU interactions, and I/O devices, ongoing developments in the computer industry are leading to more converged requirements and physical implementations for these interconnects. As it becomes increasingly common for advanced components to contain a variety of computational devices as well as memory, the distinction between processors, memory, accelerators, and I/O devices become s increasingly blurred. As a result, the interface requirements among such components are converging. There is also a wide range of new disruptive technologies that will impact the computer market in the coming years , including 3D integration and emerging NVRAM memory. Optimal exploitation of these technologies cannot be done with the existing memory, storage, and I/O interface standards. The computer industry has historically made major advances when industry players have been able to add innovation behind a standard interface. The standard interface provides a large market for their products and enables relatively quick and widespread adoption. To enable a new wave of innovation in the form of advanced memory products and accelerators, we need a new standard interface explicitly designed to provide both the performance and flexibility to support new system integration solutions.

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TYPE Other Report YEAR 2014
DOIOSTI

Evaluation of Glare at the Ivanpah Solar Electric Generating System

Ho, Clifford K.; Sims, Cianan; Christian, Josh

The Ivanpah Solar Electric Generating System (ISEGS), located on I - 15 about 40 miles (60 km) south of Las Vegas, NV, consists of three power towers 459 ft (140 m) tall and over 170,000 reflective heliostats with a rated capacity of 390 MW. Reports of glare from the plant have been submitted by pilots and air traffic controllers and recorded by the Aviation Safety Reporting System and the California Energy Commission since 2013. Aerial and ground - based surveys of the glare were conducted in April, 2014, to identify the cause and to quantify the irradiance and potential ocular impact s of the glare . Results showed that the intense glare viewed from the airspace above ISEGS was caused by he liostats in standby mode that were aimed to the side of the receiver. Evaluation of the glare showed that the retinal irradiance and subtended source angle of the glare from the heliostats in standby were sufficient to cause significant ocular impact (pot ential for after - image) up to a distance of %7E6 miles (10 km), but the values were below the threshold for permanent eye damage . Glare from the receivers had a low potential for after - image at all ground - based monitoring locations outside of the site bound aries. A Letter to Airmen has been issued by the Federal Aviation Administration to notify pilots of the potential glare hazards. Additional measures to mitigate the potential impacts of glare from ISGES are also presented and discussed. This page intentionally left blank

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TYPE SAND Report YEAR 2014
DOIOSTIDOIOSTI

Memorandum of Understanding

Siple, Bud H.

A Memorandum of Understanding establishes a clear understanding of how an agreement is going to be implemented. The Memorandum of Understanding allows all involved to specifically understand that they are agreeing to the same thing and the terms are clearly identified. It also includes the clear distinction of functions and the level of involvement of the agencies involved. Specifically, a Memorandum of Understanding gives a chance to all of those involved in the agreement to see on paper as to what they all have agreed to.

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TYPE Other Report YEAR 2014
DOIOSTI

Examples Performance Testing Templates

Siple, Bud H.

The purpose of this Performance Testing Program Plan is to identify the process and phased approach that will be implemented at Site XYZ . The purpose of the testing program at Site XYZ is specifically designed to evaluate the effectiveness of systems that are employed at this site. This plan defines tasks to be accomplished to ensure that performance testing is conducted as effectively and efficiently as possible.

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TYPE Other Report YEAR 2014
DOIOSTI

Proposing an Abstracted Interface and Protocol for Computer Systems

Resnick, David R.; Ignatowski, Mike

While it made sense for historical reasons to develop different interfaces and protocols for memory channels, CPU to CPU interactions, and I/O devices, ongoing developments in the computer industry are leading to more converged requirements and physical implementations for these interconnects. As it becomes increasingly common for advanced components to contain a variety of computational devices as well as memory, the distinction between processors, memory, accelerators, and I/O devices becomes increasingly blurred. As a result, the interface requirements among such components are converging. There is also a wide range of new disruptive technologies that will impact the computer market in the coming years, including 3D integration and emerging NVRAM memory. Optimal exploitation of these technologies cannot be done with the existing memory, storage, and I/O interface standards. The computer industry has historically made major advances when industry players have been able to add innovation behind a standard interface. The standard interface provides a large market for their products and enables relatively quick and widespread adoption. To enable a new wave of innovation in the form of advanced memory products and accelerators, we need a new standard interface explicitly designed to provide both the performance and flexibility to support new system integration solutions

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TYPE Other Report YEAR 2014
DOIOSTI

Experimental Datasets for Release to The Technology Cooperation Program CP 5-2-2012 from Sandia National Laboratories

Arunajatesan, Srinivasan

The datasets being released consist of cavity configurations for which measurements were made in the Sandia Trisonic Wind Tunnel (TWT) facility. The cavities were mounted on the walls (ceiling/floor) of the wind tunnel, with the approach flow boundary layer thickness dictated by the run-length from the settling chamber of the tunnel. No measurements of the boundary layer for the different cases were made explicitly. However, prior measurements of the boundary layer have been made and simulations of the tunnel from the settling chamber on have shown that this method yields the correct boundary layer thickness at the leading edge of the cavity. The measurements focused on the cavity flow field itself and the cavity wall pressures. For each of the cases, the stagnation conditions are prescribed in order to obtain the correct inflow conditions upstream of the cavity. The wind tunnel contours have been approved for public release and will be made available also.

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TYPE Other Report YEAR 2014
DOIOSTI
Results 52301–52400 of 99,299
Results 52301–52400 of 99,299