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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Assessment of toxic metals in waste personal computers

Highlights: • Waste personal computers were collected and dismantled in their main parts. • Motherboards, monitors and plastic housing were examined in their metal content. • Concentrations measured were compared to the RoHS Directive, 2002/95/EC. • Pb in motherboards and funnel glass of devices released <2006 was above the limit. • Waste personal computers need to be recycled and environmentally sound managed. - Abstract: Considering the enormous production of waste personal computers nowadays, it is obvious that the study of their composition is necessary in order to regulate their management and prevent any environmental contamination caused by their inappropriate disposal. This study aimed at determining the toxic metals content of motherboards (printed circuit boards), monitor glass and monitor plastic housing of two Cathode Ray Tube (CRT) monitors, three Liquid Crystal Display (LCD) monitors, one LCD touch screen monitor and six motherboards, all of which were discarded. In addition, concentrations of chromium (Cr), cadmium (Cd), lead (Pb) and mercury (Hg) were compared with the respective limits set by the RoHS 2002/95/EC Directive, that was recently renewed by the 2012/19/EU recast, in order to verify manufacturers’ compliance with the regulation. The research included disassembly, pulverization, digestion and chemical analyses of all the aforementioned devices. The toxic metals content of all samples was determined using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The results demonstrated that concentrations of Pb in motherboards and funnel glass of devices with release dates before 2006, that is when the RoHS Directive came into force, exceeded the permissible limit. In general, except from Pb, higher metal concentrations were detected in motherboards in comparison with plastic housing and glass samples. Finally, the results of this work were encouraging, since concentrations of metals referred in the RoHS Directive were found in lower levels than the legislative limits.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2013

Acceleration of the matrix multiplication of Radiance three phase daylighting simulations with parallel computing on heterogeneous hardware of personal computer

Building designers are increasingly relying on complex fenestration systems to reduce energy consumed for lighting and HVAC in low energy buildings. Radiance, a lighting simulation program, has been used to conduct daylighting simulations for complex fenestration systems. Depending on the configurations, the simulation can take hours or even days using a personal computer. This paper describes how to accelerate the matrix multiplication portion of a Radiance three-phase daylight simulation by conducting parallel computing on heterogeneous hardware of a personal computer. The algorithm was optimized and the computational part was implemented in parallel using OpenCL. The speed of new approach was evaluated using various daylighting simulation cases on a multicore central processing unit and a graphics processing unit. Based on the measurements and analysis of the time usage for the Radiance daylighting simulation, further speedups can be achieved by using fast I/O devices and storing the data in a binary format.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2012

Efficiency Improvement Opportunities for Personal Computer Monitors. Implications for Market Transformation Programs

Displays account for a significant portion of electricity consumed in personal computer (PC) use, and global PC monitor shipments are expected to continue to increase. We assess the market trends in the energy efficiency of PC monitors that are likely to occur without any additional policy intervention and estimate that display efficiency will likely improve by over 40% by 2015 compared to today’s technology. We evaluate the cost effectiveness of a key technology which further improves efficiency beyond this level by at least 20% and find that its adoption is cost effective. We assess the potential for further improving efficiency taking into account the recent development of universal serial bus (USB) powered liquid crystal display (LCD) monitors and find that the current technology available and deployed in USB powered monitors has the potential to deeply reduce energy consumption by as much as 50%. We provide insights for policies and programs that can be used to accelerate the adoption of efficient technologies to capture global energy saving potential from PC monitors which we estimate to be 9.2 terawatt-hours [TWh] per year in 2015.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2013

A COMPARISON OF DOSE RESULTS FROM THE CLEAN AIR ACT ASSESSMENT PACKAGE-1988, PERSONAL COMPUTER (CAP88-PC), VERSION 3 TO PREVIOUS VERSIONS

EPA-approved computer software packages, including CAP88-PC, are used by Department of Energy sites to demonstrate compliance with the radionuclide air emission standard under the Clean Air Act. The most recent update, CAP88-PC version 3, was approved by EPA in February 2006 for use by Department of Energy facilities. Version 3 incorporates several major changes that have the potential to affect calculated doses relative to calculations using earlier versions. This analysis examined the types and magnitudes of changes to dose estimates for specific radionuclides calculated using the version 3 software compared with the previous versions. Total effective dose calculated with version 3 was compared to effective dose equivalent calculated with previous versions for parent radionuclides and for the total dose from radionuclide chains. Various comparisons were also performed to determine which of the updates in version 3 accounted for changes in overall dose estimates. CAP88-PC version 3 would produce substantially different results relative to previous versions of the code for a number of radionuclides, including some isotopes that may be present at Department of Energy facilities, as well as those used for industrial and medical applications. In general, doses for many radionuclides are lower using version 3 but doses for a few key radionuclides would be higher.

Rhoads, Kathleen↗
DOE OSTI2011

Recycling of WEEE: Characterization of spent printed circuit boards from mobile phones and computers

Highlights: > This paper presents new and important data on characterization of wastes of electric and electronic equipments. > Copper concentration is increasing in mobile phones and remaining constant in personal computers. > Printed circuit boards from mobile phones and computers would not be mixed prior treatment. - Abstract: This paper presents a comparison between printed circuit boards from computers and mobile phones. Since printed circuits boards are becoming more complex and smaller, the amount of materials is constantly changing. The main objective of this work was to characterize spent printed circuit boards from computers and mobile phones applying mineral processing technique to separate the metal, ceramic, and polymer fractions. The processing was performed by comminution in a hammer mill, followed by particle size analysis, and by magnetic and electrostatic separation. Aqua regia leaching, loss-on-ignition and chemical analysis (inductively coupled plasma atomic emission spectroscopy - ICP-OES) were carried out to determine the composition of printed circuit boards and the metal rich fraction. The composition of the studied mobile phones printed circuit boards (PCB-MP) was 63 wt.% metals; 24 wt.% ceramics and 13 wt.% polymers; and of the printed circuit boards from studied personal computers (PCB-PC) was 45 wt.% metals; 27 wt.% polymers and ceramics 28 wt.% ceramics. The chemical analysis showed that copper concentration in printed circuit boards from personal computers was 20 wt.% and in printed circuit boards from mobile phones was 34.5 wt.%. According to the characteristics of each type of printed circuit board, the recovery of precious metals may be the main goal of the recycling process of printed circuit boards from personal computers and the recovery of copper should be the main goal of the recycling process of printed circuit boards from mobile phones. Hence, these printed circuit boards would not be mixed prior treatment. The results of this paper show that copper concentration is increasing in mobile phones and remaining constant in personal computers.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

POINT 2011: ENDF/B-VII.1 Beta2 Temperature Dependent Cross Section Library

This report is one in the series of 'POINT' reports that over the years have presented temperature dependent cross sections for the then current version of ENDF/B. In each case I have used my personal computer at home and publicly available data and codes. I have used these in combination to produce the temperature dependent cross sections used in applications and presented in this report. I should mention that today anyone with a personal computer can produce these results. The latest ENDF/B-VII.1 beta2 data library was recently and is now freely available through the National Nuclear Data Center (NNDC), Brookhaven National Laboratory. This release completely supersedes all preceding releases of ENDF/B. As distributed the ENDF/B-VII.1 data includes cross sections represented in the form of a combination of resonance parameters and/or tabulated energy dependent cross sections, nominally at 0 Kelvin temperature. For use in our applications the ENDF/B-VII.1 library has been processed into cross sections at eight neutron reactor like temperatures, between 0 and 2100 Kelvin, in steps of 300 Kelvin (the exception being 293.6 Kelvin, for exact room temperature at 20 Celsius). It has also been processed to five astrophysics like temperatures, 1, 10, 100 eV, 1 and 10 keV. For reference purposes, 300 Kelvin is approximately 1/40 eV, so that 1 eV is approximately 12,000 Kelvin. At each temperature the cross sections are tabulated and linearly interpolable in energy. All results are in the computer independent ENDF-6 character format [R2], which allows the data to be easily transported between computers. In its processed form the POINT 2011 library is approximately 16 gigabyte in size and is distributed on one compressed DVDs (see, below for the details of the contents of each DVD).

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Comparison of typical year and multiyear building simulations using a 55-year actual weather data set from China

Weather has significant impacts on the thermal environment and energy use in buildings. Thus, accurate weather data are crucial for building performance evaluations. Traditionally, typical year data inputs are used to represent long-term weather data. However, there is no guarantee that a single year represents the changing climate well. In this study, the long-term representation of a typical year was assessed by comparing it to a 55-year actual weather data set. To investigate the weather impact on building energy use, 559 simulation runs of a prototype office building were performed for 10 large cities covering all climate zones in China. The analysis results demonstrated that the weather data varied significantly from year to year. Hence, a typical year cannot reflect the variation range of weather fluctuations. Typical year simulations overestimated or underestimated the energy use and peak load in many cases. With the increase in computational power of personal computers, it is feasible and essential to adopt multiyear simulations for full assessments of long-term building performance, as this will improve decision-making by allowing for the full consideration of variations in building energy use.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

A Plug-Loads Game Changer: Computer Gaming Energy Efficiency without Performance Compromise

Two-thirds of Americans play computer games. Although among the most complex and energy intensive plug loads, gaming has been largely overlooked in energy research and development and policy. Systems used for computer gaming in California consumed 4.1 terawatt-hours/year in 2016 or $700 million in energy bills, with emissions of 1.5 million tons carbon dioxide equivalent allocated 66 percent to consoles, 31 percent to desktop personal computers, 3 percent to laptops, and less than 1 percent to emerging media streaming devices. Key findings include: • Aggregate energy demand places gaming among the top plug loads in California, with gaming representing one-fifth of the state’s total miscellaneous residential energy use. • Market structure changes could substantially affect statewide energy use; energy demand could rise by 114 percent by 2021 under intensified desktop gaming, or fall by 24 percent given a major shift towards consoles coupled with energy efficiency gains. • Unit energy consumption is remarkably varied across gaming platform types: across 26 systems tested, client-side electricity use ranged from 5 to more than 1,200 kWh per year, reflecting equipment choice and usage patterns. • Some emerging technologies and activities are driving energy demand higher, including processor overclocking, cloud-based gaming, higher-resolution connected displays, and virtual reality gaming. • User behavior influences gaming energy use more than technology choice; duty cycle and game choice are particularly strong drivers of demand. • Energy efficiency opportunities are substantial, about 50 percent on a per-system basis for personal computers and 40 percent for consoles if past rates of improvement continue. While simultaneously quantifying efficiency and gaming performance is problematic, evidence suggests that efficiency can be improved while maintaining or improving user experience. Familiar energy policy strategies can help manage gaming energy demand, although mandatory system-level standards are not promising (component-level measures may be).

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2025

UnigeneFinder: An Automated Pipeline for Gene Calling From Transcriptome Assemblies Without a Reference Genome

ABSTRACT For most species, transcriptome data are much more readily available than genome data. Without a reference genome, gene calling is cumbersome and inaccurate because of the high degree of redundancy in de novo transcriptome assemblies. To simplify and increase the accuracy of de novo transcriptome assembly in the absence of a reference genome, we developed UnigeneFinder. Combining several clustering methods, UnigeneFinder substantially reduces the redundancy typical of raw transcriptome assemblies. This pipeline offers an effective solution to the problem of inflated transcript numbers, achieving a closer representation of the actual underlying genome. UnigeneFinder performs comparably or better, compared with existing tools, on plant species with varying genome complexities. UnigeneFinder is the only available transcriptome redundancy solution that fully automates the generation of primary transcript, coding region, and protein sequences, analogous to those available for high‐quality reference genomes. These features, coupled with the pipeline’s cross‐platform implementation, focus on automation, and an accessible, user‐friendly interface, make UnigeneFinder a useful tool for many downstream sequence‐based analyses in nonmodel organisms lacking a reference genome, including differential gene expression analysis, accurate ortholog identification, functional enrichments, and evolutionary analyses. UnigeneFinder also runs efficiently both on high‐performance computing (HPC) systems and personal computers, further reducing barriers to use.

Xue, Bo [Plant Resilience Institute Michigan State↗
DOE OSTI2011

SAPHIRE 8 Volume 7 - Data Loading

The Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) is a software application developed for performing a complete probabilistic risk assessment (PRA) using a personal computer. SAPHIRE Version 8 is funded by the U.S. Nuclear Regulatory Commission and developed by the Idaho National Laboratory. This report is intended to assist the user to enter PRA data into the SAPHIRE program using the built-in MAR-D ASCII-text file data transfer process. Towards this end, a small sample database is constructed and utilized for demonstration. Where applicable, the discussion includes how the data processes for loading the sample database relate to the actual processes used to load a larger PRA models. The procedures described herein were developed for use with SAPHIRE Version 8. The guidance specified in this document will allow a user to have sufficient knowledge to both understand the data format used by SAPHIRE and to carry out the transfer of data between different PRA projects.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2012

xdamp Version 6: An IDL®-based Data and Image Manipulation Program

The original DAMP (DAta Manipulation Program) was written by Mark Hedemann of Sandia National Laboratories and used the CA-DISSPLA™ (available from Computer Associates International, Inc., Garden City, NY) graphics package as its engine. It was used to plot, modify, and otherwise manipulate the one-dimensional data waveforms (data vs. time) from a wide variety of accelerators. With the waning of CA-DISSPLA and the increasing popularity of Unix®-based workstations, a replacement was needed. This package uses the IDL® software, available from Research Systems Incorporated, a Xerox company, in Boulder, Colorado, as the engine, and creates a set of widgets to manipulate the data in a manner similar to the original DAMP and earlier versions of xdamp. IDL is currently supported on a wide variety of Unix platforms such as IBM® workstations, Hewlett Packard workstations, SUN® workstations, Microsoft® Windows™ computers, Macintosh® computers and Digital Equipment Corporation VMS® and Alpha® systems. Thus, xdamp is portable across many platforms. We have verified operation, albeit with some minor IDL bugs, on personal computers using Windows 7 and Windows Vista; Unix platforms; and Macintosh computers. Version 6 is an update that uses the IDL Virtual Machine to resolve the need for licensing IDL.

43 PARTICLE ACCELERATORS↗
DOE OSTI2011

A preliminary categorization of end-of-life electrical and electronic equipment as secondary metal resources

Highlights: > End-of-life electrical and electronic equipment (EEE) as secondary metal resources. > The content and the total amount of metals in specific equipment are both important. > We categorized 21 EEE types from contents and total amounts of various metals. > Important equipment types as secondary resources were listed for each metal kind. > Collectability and possible collection systems of various EEE types were discussed. - Abstract: End-of-life electrical and electronic equipment (EEE) has recently received attention as a secondary source of metals. This study examined characteristics of end-of-life EEE as secondary metal resources to consider efficient collection and metal recovery systems according to the specific metals and types of EEE. We constructed an analogy between natural resource development and metal recovery from end-of-life EEE and found that metal content and total annual amount of metal contained in each type of end-of-life EEE should be considered in secondary resource development, as well as the collectability of the end-of-life products. We then categorized 21 EEE types into five groups and discussed their potential as secondary metal resources. Refrigerators, washing machines, air conditioners, and CRT TVs were evaluated as the most important sources of common metals, and personal computers, mobile phones, and video games were evaluated as the most important sources of precious metals. Several types of small digital equipment were also identified as important sources of precious metals; however, mid-size information and communication technology (ICT) equipment (e.g., printers and fax machines) and audio/video equipment were shown to be more important as a source of a variety of less common metals. The physical collectability of each type of EEE was roughly characterized by unit size and number of end-of-life products generated annually. Current collection systems in Japan were examined and potentially appropriate collection methods were suggested for equipment types that currently have no specific collection systems in Japan, particularly for video games, notebook computers, and mid-size ICT and audio/video equipment.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2014

Implementation of data acquisition interface using on-board field-programmable gate array (FPGA) universal serial bus (USB) link

Typically a system consists of hardware as the controller and software which is installed in the personal computer (PC). In the effective nuclear detection, the hardware involves the detection setup and the electronics used, with the software consisting of analysis tools and graphical display on PC. A data acquisition interface is necessary to enable the communication between the controller hardware and PC. Nowadays, Universal Serial Bus (USB) has become a standard connection method for computer peripherals and has replaced many varieties of serial and parallel ports. However the implementation of USB is complex. This paper describes the implementation of data acquisition interface between a field-programmable gate array (FPGA) board and a PC by exploiting the USB link of the FPGA board. The USB link is based on an FTDI chip which allows direct access of input and output to the Joint Test Action Group (JTAG) signals from a USB host and a complex programmable logic device (CPLD) with a 24 MHz clock input to the USB link. The implementation and results of using the USB link of FPGA board as the data interfacing are discussed.

42 ENGINEERING↗
DOE OSTI2012

Dose calculation software for helical tomotherapy, utilizing patient CT data to calculate an independent three-dimensional dose cube

Purpose: Treatment plans for the TomoTherapy unit are produced with a planning system that is integral to the unit. The authors have produced an independent dose calculation system, to enable plans to be recalculated in three dimensions, using the patient's CT data. Methods: Software has been written using MATLAB. The DICOM-RT plan object is used to determine the treatment parameters used, including the treatment sinogram. Each projection of the sinogram is segmented and used to calculate dose at multiple calculation points in a three-dimensional grid using tables of measured beam data. A fast ray-trace algorithm is used to determine effective depth for each projection angle at each calculation point. Calculations were performed on a standard desktop personal computer, with a 2.6 GHz Pentium, running Windows XP. Results: The time to perform a calculation, for 3375 points averaged 1 min 23 s for prostate plans and 3 min 40 s for head and neck plans. The mean dose within the 50% isodose was calculated and compared with the predictions of the TomoTherapy planning system. When the modified CT (which includes the TomoTherapy couch) was used, the mean difference for ten prostate patients, was -0.4% (range -0.9% to +0.3%). With the original CT (which included the CT couch), the mean difference was -1.0% (range -1.7% to 0.0%). The number of points agreeing with a gamma 3%/3 mm averaged 99.2% with the modified CT, 96.3% with the original CT. For ten head and neck patients, for the modified and original CT, respectively, the mean difference was +1.1% (range -0.4% to +3.1%) and 1.1% (range -0.4% to +3.0%) with 94.4% and 95.4% passing a gamma 4%/4 mm. The ability of the program to detect a variety of simulated errors has been tested. Conclusions: By using the patient's CT data, the independent dose calculation performs checks that are not performed by a measurement in a cylindrical phantom. This enables it to be used either as an additional check or to replace phantom measurements for some patients. The software has potential to be used in any application where one wishes to model changes to patient conditions.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Generation of and control measures for, e-waste in Hong Kong

While accurately estimating electrical and electronic waste (e-waste) generation is important for building appropriate infrastructure for its collection and recycling, making reliable estimates of this kind is difficult in Hong Kong owing to the fact that neither accurate trade statistics nor sales data of relevant products are available. In view of this, data of e-products consumption at household level was collected by a tailor-made questionnaire survey from the public for obtaining a reasonable e-waste generation estimate. It was estimated that on average no more than 80,443 tonnes (11.5 kg/capita) of waste is generated from non-plasma and non-liquid crystal display televisions, refrigerators, washing machines, air-conditioners and personal computers each year by Hong Kong households. However, not more than 17% of this is disposed as waste despite a producer responsibility scheme (PRS) not being in place because of the existence of a vibrant e-waste trading sector. The form of PRS control that can possibly win most public support is one that would involve the current e-waste traders as a major party in providing the reverse logistics with a visible recycling charge levied at the point of importation. This reverse logistic service should be convenient, reliable and highly accessible to the consumers.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

Evaluation of Effective Dose During Abdominal Three-Dimensional Imaging for Three Flat-Panel-Detector Angiography Systems

The purpose of this study was to evaluate the effective dose during abdominal three-dimensional (3D) imaging on phantoms and estimate the dose-area product (DAP) for effective dose conversion factors for three types of angiographic units. Three-dimensional imaging was performed for three sizes (small, medium, large) of human-shaped phantoms using three types of angiographic units (Allura Xper FD20/10, INNOVA 4100, AXIOM Artis dTA). We calculated 25 organ doses and effective doses using Monte Carlo technique for the three phantoms with a program for a personal computer. As benchmark studies to back up the results by Monte Carlo technique, we measured the organ doses directly on the small phantom using radiophotoluminescent glass dosimeters. The DAP value increased as the phantom size increased. The organ doses and the effective doses during the 3D imaging increased as the phantom size increased. The effective doses for the small phantom by Monte Carlo technique were 1.9, 2.2, and 2.1 mSv for the Allura Xper FD20/10, INNOVA 4100, and AXIOM Artis dTA, respectively, while those by direct measurement were 1.6, 2.0, and 2.6 mSv. The effective doses to DAP ratios by Monte Carlo technique were 0.37-0.45, 0.26-0.32, and 0.13-0.15 (mSv Gy{sup -1}cm{sup -2}) for the Allura Xper FD20/10, INNOVA 4100, and AXIOM Artis dTA, respectively. In conclusion, the effective doses during 3D imaging and the dose-to-DAP ratios differ among angiographic units, and the effective dose can be estimated using a proper conversion factor for each angiographic unit.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Framework for Analysis and Visualization of Simulation Data (VizAly)

As supercomputing resources increase, cosmological scientists are able to run more detailed and larger simulations generating massive amounts of data. Analyzing these simulations with an available open-source toolkit is important for collaborative Department of Energy scientific discovery across labs, universities, and other partners. Developed software as a part of this collection include: comparing data with other existing simulations, verifying and validating results with observation databases, new halo finder algorithms, and using analytical tools to get insights into the physics of the cosmological universe. The goal of this software project is to provide a set of open-source libraries, tools, and packages for large-scale cosmology that allows scientists to visualize, analyze, and compare large-scale simulation and observational data sets. Developed software will provide a variety of methods for processing, visualization, and analysis of astronomical observation and cosmological simulation data. These tools are intended for deployment on multiple scientific computing platforms, including but not limited to personal computers, cloud computing, experimental sites (telescopes) and high performance supercomputers.

Wendelberger, Joanne↗