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At least 379 records · Page 21

Proposed Project Selection Method for Human Support Research and Technology Development (HSR&TD)

The purpose of HSR&TD is to deliver human support technologies to the Exploration Systems Mission Directorate (ESMD) that will be selected for future missions. This requires identifying promising candidate technologies and advancing them in technology readiness until they are acceptable. HSR&TD must select an may of technology development projects, guide them, and either terminate or continue them, so as to maximize the resulting number of usable advanced human support technologies. This paper proposes an effective project scoring methodology to support managing the HSR&TD project portfolio. Researchers strongly disagree as to what are the best technology project selection methods, or even if there are any proven ones. Technology development is risky and outstanding achievements are rare and unpredictable. There is no simple formula for success. Organizations that are satisfied with their project selection approach typically use a mix of financial, strategic, and scoring methods in an open, established, explicit, formal process. This approach helps to build consensus and develop management insight. It encourages better project proposals by clarifying the desired project attributes. We propose a project scoring technique based on a method previously used in a federal laboratory and supported by recent research. Projects are ranked by their perceived relevance, risk, and return - a new 3 R's. Relevance is the degree to which the project objective supports the HSR&TD goal of developing usable advanced human support technologies. Risk is the estimated probability that the project will achieve its specific objective. Return is the reduction in mission life cycle cost obtained if the project is successful. If the project objective technology performs a new function with no current cost, its return is the estimated cash value of performing the new function. The proposed project selection scoring method includes definitions of the criteria, a project evaluation questionnaire, and a scoring formula.

Jones, Harry↗

The role of client engagement in successful project delivery - 15599

Projects, managed using one of the standard methodologies, are the primary vehicle used by most organizations to effectively deliver their strategic objectives in a timely and high quality manner. Most projects at ANSTO with a strong nuclear technology component require the active engagement of the end user, sponsor and subject matter experts for making key decisions during the project delivery phase to ensure best value for the organization. In 2009, after a review of ANSTO's project governance and management processes, a number of changes to the governance of internal projects were made. This included the establishment of a project governance structure that includes a two-point accountability framework, where the Project Client, together with the Project Manager is held accountable for the project delivery. While the two-point project accountability framework is not a conventional approach in project management, the experience from the project managers and stakeholders at ANSTO indicates that it provides a robust, consistent and practical approach for managing projects. The challenges of the two-point accountability framework are primarily related to the clarity of roles and goals, particularly from the Client perspective. This is an area that needs further attention. Overall, this approach allows better coordination of input from the project sponsors, end users and subject matter experts for day-to-day decision making through the life-cycle of the project. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

The Off-Site Plowshare and Vela Uniform Programs: Assessing Potential Environmental Liabilities through an Examination of Proposed Nuclear Projects, High Explosive Experiments, and High Explosive Construction Activities: Volume 1 of 3

This document presents the results of nearly six years (2002-2008) of historical research and field studies concerned with evaluating potential environmental liabilities associated with U.S. Atomic Energy Commission projects from the Plowshare and Vela Uniform Programs. The Plowshare Program's primary purpose was to develop peaceful uses for nuclear explosives. The Vela Uniform Program focused on improving the capability of detecting, monitoring and identifying underground nuclear detonations. As a result of the Project Chariot site restoration efforts in the early 1990s, there were concerns that there might be other project locations with potential environmental liabilities. The Desert Research Institute conducted archival research to identify projects, an analysis of project field activities, and completed field studies at locations where substantial fieldwork had been undertaken for the projects. Although the Plowshare and Vela Uniform nuclear projects are well known, the projects that are included in this research are relatively unknown. They are proposed nuclear projects that were not executed, proposed and executed high explosive experiments, and proposed and executed high explosive construction activities off the Nevada Test Site. The research identified 170 Plowshare and Vela Uniform off-site projects and many of these had little or no field activity associated with them. However, there were 27 projects that merited further investigation and field studies were conducted at 15 locations.

(2002-2008)↗

The Off-Site Plowshare and Vela Uniform Programs: Assessing Potential Environmental Liabilities through an Examination of Proposed Nuclear Projects, High Explosive Experiments, and High Explosive Construction Activities: Volume 2 of 3

This document presents the results of nearly six years (2002-2008) of historical research and field studies concerned with evaluating potential environmental liabilities associated with U.S. Atomic Energy Commission projects from the Plowshare and Vela Uniform Programs. The Plowshare Program's primary purpose was to develop peaceful uses for nuclear explosives. The Vela Uniform Program focused on improving the capability of detecting, monitoring and identifying underground nuclear detonations. As a result of the Project Chariot site restoration efforts in the early 1990s, there were concerns that there might be other project locations with potential environmental liabilities. The Desert Research Institute conducted archival research to identify projects, an analysis of project field activities, and completed field studies at locations where substantial fieldwork had been undertaken for the projects. Although the Plowshare and Vela Uniform nuclear projects are well known, the projects that are included in this research are relatively unknown. They are proposed nuclear projects that were not executed, proposed and executed high explosive experiments, and proposed and executed high explosive construction activities off the Nevada Test Site. The research identified 170 Plowshare and Vela Uniform off-site projects and many of these had little or no field activity associated with them. However, there were 27 projects that merited further investigation and field studies were conducted at 15 locations.

(2002-2008)↗

The Off-Site Plowshare and Vela Uniform Programs: Assessing Potential Environmental Liabilities through an Examination of Proposed Nuclear Projects, High Explosive Experiments, and High Explosive Construction Activities: Volume 3 of 3

This document presents the results of nearly six years (2002-2008) of historical research and field studies concerned with evaluating potential environmental liabilities associated with U.S. Atomic Energy Commission projects from the Plowshare and Vela Uniform Programs. The Plowshare Program's primary purpose was to develop peaceful uses for nuclear explosives. The Vela Uniform Program focused on improving the capability of detecting, monitoring and identifying underground nuclear detonations. As a result of the Project Chariot site restoration efforts in the early 1990s, there were concerns that there might be other project locations with potential environmental liabilities. The Desert Research Institute conducted archival research to identify projects, an analysis of project field activities, and completed field studies at locations where substantial fieldwork had been undertaken for the projects. Although the Plowshare and Vela Uniform nuclear projects are well known, the projects that are included in this research are relatively unknown. They are proposed nuclear projects that were not executed, proposed and executed high explosive experiments, and proposed and executed high explosive construction activities off the Nevada Test Site. The research identified 170 Plowshare and Vela Uniform off-site projects and many of these had little or no field activity associated with them. However, there were 27 projects that merited further investigation and field studies were conducted at 15 locations.

(2002-2008)↗

Poster — Thur Eve — 01: The effect of the number of projections on MTF and CNR in Compton scatter tomography

Purpose: To investigate the dependence of the reconstructed image quality on the number of projections in multi-projection Compton scatter tomography (MPCST). The conventional relationship between the projection number used for reconstruction and reconstructed image quality pertained to CT does not necessarily apply to MPCST, which can produce images from a single projection if the detectors have sufficiently high energy and spatial resolution. Methods: The electron density image was obtained using filtered-backprojection of the scatter signal over circular arcs formed using Compton equation. The behavior of the reconstructed image quality as a function of the projection number was evaluated through analytical simulations and characterized by CNR and MTF. Results: The increase of the projection number improves the contrast with this dependence being a function of fluence. The number of projections required to approach the asymptotic maximum contrast decreases as the fluence increases. Increasing projection number increases the CNR but not spatial resolution. Conclusions: For MPCST using a 500eV energy resolution and a 2×2mm{sup 2} size detector, an adequate image quality can be obtained with a small number of projections provided the incident fluence is high enough. This is conceptually different from conventional CT where a minimum number of projections is required to obtain an adequate image quality. While increasing projection number, even for the lowest dose value, the CNR increases even though the number of photons per projection decreases. The spatial resolution of the image is improved by increasing the sampling within a projection rather than by increasing the number of projections.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Final Technical Report - Modernization of the Boulder Canyon Hydroelectric Project

The Boulder Canyon Hydroelectric Project (BCH) was purchased by the City of Boulder, CO (the city) in 2001. Project facilities were originally constructed in 1910 and upgraded in the 1930s and 1940s. By 2009, the two 10 MW turbine/generators had reached or were nearing the end of their useful lives. One generator had grounded out and was beyond repair, reducing plant capacity to 10 MW. The remaining 10 MW unit was expected to fail at any time. When the BCH power plant was originally constructed, a sizeable water supply was available for the sole purpose of hydroelectric power generation. Between 1950 and 2001, that water supply had gradually been converted to municipal water supply by the city. By 2001, the water available for hydroelectric power generation at BCH could not support even one 10 MW unit. Boulder lacked the financial resources to modernize the facilities, and Boulder anticipated that when the single, operational historical unit failed, the project would cease operation. In 2009, the City of Boulder applied for and received a U.S. Department of Energy (DOE) grant for $1.18 million toward a total estimated project cost of $5.155 million to modernize BCH. The federal funding allowed Boulder to move forward with plant modifications that would ensure BCH would continue operation. Federal funding was made available through the American Recovery and Reinvestment Act (ARRA) of 2009. Boulder determined that a single 5 MW turbine/generator would be the most appropriate capacity, given the reduced water supply to the plant. Average annual BCH generation with the old 10 MW unit had been about 8,500 MW-hr, whereas annual generation with a new, efficient turbine could average 11,000 to 12,000 MW-hr. The incremental change in annual generation represents a 30% increase in generation over pre-project conditions. The old turbine/generator was a single nozzle Pelton turbine with a 5-to-1 flow turndown and a maximum turbine/generator efficiency of 82%. The new unit is a double nozzle Pelton turbine with a 10-to-1 flow turndown and a maximum turbine/generator efficiency of 88%. This alone represents a 6% increase in overall efficiency. The old turbine operated at low efficiencies due to age and non-optimal sizing of the turbine for the water flow available to the unit. It was shut down whenever water flow dropped to less than 4-5 cfs, and at that flow, efficiency was 55 to 60%. The new turbine will operate in the range of 70 to 88% efficiency through a large portion of the existing flow range and would only have to be shut down at flow rates less than 3.7 cfs. Efficiency is expected to increase by 15-30%, depending on flow. In addition to the installation of new equipment, other goals for the project included: Increasing safety at Boulder Canyon Hydro Increasing protection of the Boulder Creek environment Modernizing and integrating control equipment into Boulder's municipal water supply system, and Preserving significant historical engineering information prior to power plant modernization. From January 1, 2010 through December 31, 2012, combined consultant and contractor personnel hours paid for by both the city and the federal government have totaled approximately 40,000. This equates roughly to seven people working full time on the project from January 2010 through December 2012. This project also involved considerable material expense (steel pipe, a variety of valves, electrical equipment, and the various components of the turbine and generator), which were not accounted for in terms of hours spent on the project. However, the material expense related to this project did help to create or preserve manufacturing/industrial jobs throughout the United States. As required by ARRA, the various components of the hydroelectric project were manufactured or substantially transformed in the U.S. BCH is eligible for nomination to the National Register of Historic Places due in part to its unique engineering features and innovative construction techniques. Special efforts were directed toward documenting the (largely original) interior of the plant and installing new equipment without modifying the power plant exterior in order to preserve the historical significance of the facility. In addition, a significant portion of the historical equipment within the power plant was preserved in place. The modernization project began with DOE grant award on January 1, 2010, and the project was completed on December 31, 2012. In addition to city engineering and hydroelectric staff, major project participants included AECOM (design/engineering) Canyon Industries (turbine/generator manufacture), Gracon Corporation (general construction contractor), Exponential Engineering Company (electrical engineering) and URS Corporation (historical documentation), as well as numerous other subcontractors and consultants.

13 HYDRO ENERGY↗

Evolution of the U.S. Energy Service Company Industry: Market Size and Project Performance from 1990-2008

The U.S. energy service company (ESCO) industry is an example of a private sector business model where energy savings are delivered to customers primarily through the use of performance-based contracts. This study was conceived as a snapshot of the ESCO industry prior to the economic slowdown and the introduction of federal stimulus funding mandated by enactment of the American Recovery and Reinvestment Act of 2009 (ARRA). This study utilizes two parallel analytic approaches to characterize ESCO industry and market trends in the U.S.: (1) a “top-down” approach involving a survey of individual ESCOs to estimate aggregate industry activity and (2) a “bottom-up” analysis of a database of -3,265 projects (representing over $8B in project investment) that reports market trends including installed EE retrofit strategies, project installation costs and savings, project payback times, and benefit-cost ratios over time. Despite the onset of an economic recession, the U.S. ESCO industry managed to grow at about 7% per year between 2006 and 2008. ESCO industry revenues are relatively small compared to total U.S. energy expenditures (about $4.1 billion in 2008), but ESCOs anticipated accelerated growth through 2011 (25% per year). We found that 2,484 ESCO projects in our database generated -$4.0 billion ($2009) in net, direct economic benefits to their customers. We estimate that the ESCO project database includes about 20% of all U.S. ESCO market activity from 1990-2008. Assuming the net benefits per project are comparable for ESCO projects that are not included in the LBNL database, this would suggest that the ESCO industry has generated -$23 billion in net direct economic benefits for customers at projects installed between 1990 and 2008. We found that nearly 85% of all public and institutional projects met or exceeded the guaranteed level of savings. We estimated that a typical ESCO project generated $1.5 dollars of direct benefits for every dollar of customer investment. There is empirical evidence confirming that the industry is responding to customer demand by installing more comprehensive and complex measures—including onsite generation and measures to address deferred maintenance—but this evolution has significant implications for customer project economics, especially at K-12 schools. We found that the median simple payback time has increased from 1.9 to 3.2 years in private sector projects since the early-to-mid 1990s and from 5.2 to 10.5 years in public sector projects for the same time period.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Design Basis Document / Owner’s Technical Specification for Nitrate Salt Systems in CSP Projects (Final Technical Report)

The number of commercial coal, gas, and nuclear projects built over the past 100 years number in the thousands. As such, there is a large database, available to a wide range of commercial engineering contractors, on proven designs. In essence, unsuccessful designs have, through generations of iterations, been identified and then deleted from further consideration. In contrast, the number of commercial parabolic trough projects using nitrate salt for the thermal storage media is perhaps 60. Further, the number of commercial central receiver projects using nitrate salt as the working fluid is on the order of 20, including estimates for China. Given the relative immaturity of salt technology, and commercial pressures to successfully bid new solar projects into a mature electricity market, solar projects often promise more than has been delivered. The Design Basis Document / Owner’s Technical Specification is a first step in the iteration process. The report describes the successful features of commercial projects, outlines a range equipment and system failures in projects that didn’t operate as intended, and provides a draft set of design changes intended to correct the known problems. The product of the study is 3 volumes of technical material; one volume is on parabolic trough technologies; a second is on central receiver technologies, and the third is on potential design changes to parabolic trough and central receiver projects. The 3 volumes, which total some 590 pages, can be found at https://www.solardynllc.com/csp-plant-technologies. One of the principal topics in the report is the use of functional or prescriptive specifications. Functional specifications describe what the equipment needs to do, consistent with the minimum legal requirements of the local jurisdictions. The details of how this is to be accomplished is developed by the engineering contractor. Prescriptive specifications, which are developed by the Owner, prescribe to the engineering contractor how the functional requirements are to be met. This arrangement ensures that the favorable experience from a previous project is repeated. One example is the design code for the hot salt tank in central receiver projects. The closest design basis is API Standard 650 Welded Steel Tanks for Oil Storage. However, the maximum design temperature in API 650 is 260 °C. As such, solar projects have typically adopted a hybrid Code approach, in which allowable material stresses are taken from ASME Section II Materials. Further, since the tanks experience daily changes in temperature and in (static) pressure, and since portions of the tank can operate at stresses beyond the elastic range, the low cycle fatigue life of the tank is conducted using the rules of Section VIII Division 2. However, in a recent study by NREL, the principal damage mechanism was identified as creep rather than fatigue. Further, design stresses permitted under Section VIII Division 2, corresponding to a fatigue life of 30 years, result in projected creep lifetimes of only 2 to 5 years. An alternate design approach, prescribed by the Owner, would be based on Code sections intended for high temperature service in the creep regime. A candidate is Section III Division 5. Granted, this is a nuclear code section, and it’s use would not likely be mandated by local jurisdictions. However, the effects of creep have been deemed to be of sufficient importance that one nuclear project developer, and one central receiver project developer, have stipulated in the tank design specification that the equipment be designed to the requirements of Section III Division 5.

14 SOLAR ENERGY↗

Guidance and Control Software Project Data - Volume 4: Configuration Management and Quality Assurance Documents

The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes configuration management and quality assurance documents from the GCS project. Volume 4 contains six appendices: A. Software Accomplishment Summary for the Guidance and Control Software Project; B. Software Configuration Index for the Guidance and Control Software Project; C. Configuration Management Records for the Guidance and Control Software Project; D. Software Quality Assurance Records for the Guidance and Control Software Project; E. Problem Report for the Pluto Implementation of the Guidance and Control Software Project; and F. Support Documentation Change Reports for the Guidance and Control Software Project.

Hayhurst, Kelly J.↗

Public participation in EIA: A comparative study of the projects run by government and non-governmental organizations

Assuring public participation in different stages of environmental impact assessment (EIA) is essential since the success of a project largely depends on its type, nature, and process. Before starting a development project in Bangladesh, both government organizations (GOs) and non-government organizations (NGOs) need to conduct an EIA. However, in most of the governmental projects, there is still no significant influence of public participation in EIA. Contrarily, under NGO administered projects, the systematic participation in EIA is quite unknown and often goes without being acknowledged. This paper, thus, studies public participation practice in EIA through an investigation of two NGO governed projects (i.e., BRAC's fisheries and sericulture project and CARE's integrated food for work program) and compares with two projects by GOs (i.e., Rampal coal-based thermal power plant project and Jamuna multipurpose bridge project) to critically understand the prevailing differences. As well, pivotal factors responsible for differentiated nature and type of public participation being practiced within a certain institutional context are examined. The study indicates that NGOs tend to ensure participation of the pertinent stakeholders at different stages of an EIA while harnessing their inputs to successfully complete a project. By contrast, public participation in government's run projects is mostly found to be carried out towards the end of an EIA exercise, which severely limits the stakeholders' ability to contribute and questions the legitimacy of such attempt. This process of neglect systematically overlooks stakeholders' concerns, critics, and suggestions while pre-emptive motive of the project gets glorified and implemented. By tapping these voids, this study attempts to offer an insightful understanding of the gap between conventional ‘practice’ and formal ‘pledge’ when comes to ensuring public participation in various stages of EIA. This study expects to benefit other countries where NGOs are considerably involved in development projects.

20 FOSSIL-FUELED POWER PLANTS↗

How a large project was halted by the lack of a social Licence to operate: Testing the applicability of the Thomson and Boutilier model

Highlights: • The lack of a Social Licence to Operate (SLO) can halt a project. • Resettlement is a significant issue in getting a Social Licence to Operate. • Legitimacy, credibility and trust are key concepts of Social Licence to Operate. • Project proponents can and should utilise the concept of Social Licence to Operate. • Earning a SLO requires considered effort and commitment from project proponents. - Abstract: We explore why having a Social Licence to Operate (SLO) is essential for large projects. We analyse the Khudoni Hydroelectric Power Plant in the Svaneti region of Georgia, which was halted in 2013 after much social protest. We assess why the project lacked a SLO and what lessons can be learnt from this experience. Using the Thomson and Boutilier model of SLO as our analytical framework, we elaborate its key elements – legitimacy, credibility and trust – in the context of dam and hydropower projects and assess where the Khudoni project failed. We conclude that the project lacked legitimacy, with local communities not seeing any social justification for the project. The credibility of the project and proponent was weak amongst the local population, and trust was absent at all phases of the project. We conclude that the concept of social licence to operate has the potential to encourage project proponents to consider and implement activities which will lead to better outcomes for all parties. We believe there is a strong business case for companies to take the concept seriously. Improving social performance will assist projects in gaining a social licence to operate and grow.

13 HYDRO ENERGY↗

Using remote sensing to quantify the additional climate benefits of California forest carbon offset projects

Abstract Nature‐based climate solutions are a vital component of many climate mitigation strategies, including California's, which aims to achieve carbon neutrality by 2045. Most carbon offsets in California's cap‐and‐trade program come from improved forest management (IFM) projects. Since 2012, various landowners have set up IFM projects following the California Air Resources Board's IFM protocol. As many of these projects approach their 10th year, we now have the opportunity to assess their effectiveness, identify best practices, and suggest improvements toward future protocol revisions. In this study, we used remote sensing‐based datasets to evaluate the carbon trends and harvest histories of 37 IFM projects in California. Despite some current limitations and biases, these datasets can be used to quantify carbon accumulation and harvest rates in offset project lands relative to nearby similar “control” lands before and after the projects began. Five lines of evidence suggest that the carbon accumulated in offset projects to date has generally not been additional to what might have otherwise occurred: (1) most forests in northwestern California have been accumulating carbon since at least the mid‐1980s and continue to accumulate carbon, whether enrolled in offset projects or not; (2) harvest rates were high in large timber company project lands before IFM initiation, suggesting they are earning carbon credits for forests in recovery; (3) projects are often located on lands with higher densities of low‐timber‐value species; (4) carbon accumulation rates have not yet increased on lands that enroll as offset projects, relative to their pre‐enrollment levels; and (5) harvest rates have not decreased on most project lands since offset project initiation. These patterns suggest that the current protocol should be improved to robustly measure and reward additionality. In general, our framework of geospatial analyses offers an important and independent means to evaluate the effectiveness of the carbon offsets program, especially as these data products continue improving and as offsets receive attention as a climate mitigation strategy.

59 BASIC BIOLOGICAL SCIENCES↗

Noise correlation in CBCT projection data and its application for noise reduction in low-dose CBCT

Purpose: To study the noise correlation properties of cone-beam CT (CBCT) projection data and to incorporate the noise correlation information to a statistics-based projection restoration algorithm for noise reduction in low-dose CBCT. Methods: In this study, the authors systematically investigated the noise correlation properties among detector bins of CBCT projection data by analyzing repeated projection measurements. The measurements were performed on a TrueBeam onboard CBCT imaging system with a 4030CB flat panel detector. An anthropomorphic male pelvis phantom was used to acquire 500 repeated projection data at six different dose levels from 0.1 to 1.6 mAs per projection at three fixed angles. To minimize the influence of the lag effect, lag correction was performed on the consecutively acquired projection data. The noise correlation coefficient between detector bin pairs was calculated from the corrected projection data. The noise correlation among CBCT projection data was then incorporated into the covariance matrix of the penalized weighted least-squares (PWLS) criterion for noise reduction of low-dose CBCT. Results: The analyses of the repeated measurements show that noise correlation coefficients are nonzero between the nearest neighboring bins of CBCT projection data. The average noise correlation coefficients for the first- and second-order neighbors are 0.20 and 0.06, respectively. The noise correlation coefficients are independent of the dose level. Reconstruction of the pelvis phantom shows that the PWLS criterion with consideration of noise correlation (PWLS-Cor) results in a lower noise level as compared to the PWLS criterion without considering the noise correlation (PWLS-Dia) at the matched resolution. At the 2.0 mm resolution level in the axial-plane noise resolution tradeoff analysis, the noise level of the PWLS-Cor reconstruction is 6.3% lower than that of the PWLS-Dia reconstruction. Conclusions: Noise is correlated among nearest neighboring detector bins of CBCT projection data. An accurate noise model of CBCT projection data can improve the performance of the statistics-based projection restoration algorithm for low-dose CBCT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

SU-E-J-167: Improvement of Time-Ordered Four Dimensional Cone-Beam CT; Image Mosaicing with Real and Virtual Projections

Purpose: In the previous study, we developed time-ordered fourdimensional (4D) cone-beam CT (CBCT) technique to visualize nonperiodic organ motion, such as peristaltic motion of gastrointestinal organs and adjacent area, using half-scan reconstruction method. One important obstacle was that truncation of projection was caused by asymmetric location of flat-panel detector (FPD) in order to cover whole abdomen or pelvis in one rotation. In this study, we propose image mosaicing to extend projection data to make possible to reconstruct full field-of-view (FOV) image using half-scan reconstruction. Methods: The projections of prostate cancer patients were acquired using the X-ray Volume Imaging system (XVI, version 4.5) on Synergy linear accelerator system (Elekta, UK). The XVI system has three options of FOV, S, M and L, and M FOV was chosen for pelvic CBCT acquisition, with a FPD panel 11.5 cm offset. The method to produce extended projections consists of three main steps: First, normal three-dimensional (3D) reconstruction which contains whole pelvis was implemented using real projections. Second, virtual projections were produced by reprojection process of the reconstructed 3D image. Third, real and virtual projections in each angle were combined into one extended mosaic projection. Then, 4D CBCT images were reconstructed using our inhouse reconstruction software based on Feldkamp, Davis and Kress algorithm. The angular range of each reconstruction phase in the 4D reconstruction was 180 degrees, and the range moved as time progressed. Results: Projection data were successfully extended without discontinuous boundary between real and virtual projections. Using mosaic projections, 4D CBCT image sets were reconstructed without artifacts caused by the truncation, and thus, whole pelvis was clearly visible. Conclusion: The present method provides extended projections which contain whole pelvis. The presented reconstruction method also enables time-ordered 4D CBCT reconstruction of organs with non-periodic motion with full FOV without projection-truncation artifacts. This work was partly supported by the JSPS Core-to-Core Program(No. 23003). This work was partly supported by JSPS KAKENHI 24234567.

60 APPLIED LIFE SCIENCES↗

TH-A-18C-03: Noise Correlation in CBCT Projection Data and Its Application for Noise Reduction in Low-Dose CBCT

Purpose: To study the noise correlation properties of cone-beam CT (CBCT) projection data and to incorporate the noise correlation information to a statistics-based projection restoration algorithm for noise reduction in low-dose CBCT. Methods: In this study, we systematically investigated the noise correlation properties among detector bins of CBCT projection data by analyzing repeated projection measurements. The measurements were performed on a TrueBeam on-board CBCT imaging system with a 4030CB flat panel detector. An anthropomorphic male pelvis phantom was used to acquire 500 repeated projection data at six different dose levels from 0.1 mAs to 1.6 mAs per projection at three fixed angles. To minimize the influence of the lag effect, lag correction was performed on the consecutively acquired projection data. The noise correlation coefficient between detector bin pairs was calculated from the corrected projection data. The noise correlation among CBCT projection data was then incorporated into the covariance matrix of the penalized weighted least-squares (PWLS) criterion for noise reduction of low-dose CBCT. Results: The analyses of the repeated measurements show that noise correlation coefficients are non-zero between the nearest neighboring bins of CBCT projection data. The average noise correlation coefficients for the first- and second- order neighbors are about 0.20 and 0.06, respectively. The noise correlation coefficients are independent of the dose level. Reconstruction of the pelvis phantom shows that the PWLS criterion with consideration of noise correlation (PWLS-Cor) results in a lower noise level as compared to the PWLS criterion without considering the noise correlation (PWLS-Dia) at the matched resolution. Conclusion: Noise is correlated among nearest neighboring detector bins of CBCT projection data. An accurate noise model of CBCT projection data can improve the performance of the statistics-based projection restoration algorithm for low-dose CBCT.

60 APPLIED LIFE SCIENCES↗

U.S. China Carbon Capture and Storage Development Project at West Virginia University

The original overall objective of this activity was to undertake resource evaluation and planning for CCS projects and to describe and quantify the geologic, environmental, and economic challenges to successful development of large-scale CCS in China’s coal sector. Several project execution barriers were encountered in the course of this project, most notably a project stop/delay due to funds availability/costing restrictions from the US State Department to the US Department of Energy at the end of CY2012, which halted project execution from January 2, 2013 to April 1, 2013. At the resolution of this project delay, it was communicated to the project team that the overall project period would also be reduced, from a completion date of February 28, 2014 to December 31, 2013. The net impact of all these changes was a reduction in the project period from 24 months (3/1/2012-2/28/2014) to 22 months (3/1/2012-12/31/2013), with a 3 month stop from 1/1/2013-3/31/2013. The project team endeavored to overcome these project time impacts, focusing heavily on technoeconomic modeling that would be deliverable under Task 3 (Ordos Basin Feasibility Study), and choosing to abandon the full investigation into the Demonstration Site (Task 4) due to the reduced project time. The ultimate focus of this project changed to work with the Chinese on a carbon atlas/geologic characterization, and on mechanisms for CO2 storage options from high-quality streams within China.

20 FOSSIL-FUELED POWER PLANTS↗

Exe-Guard Project

The exe-Guard Project is an alliance between Dominion Virginia Power (DVP), Sandia National Laboratories (SNL), Dartmouth University, and Schweitzer Engineering Laboratories (SEL). SEL is primary recipient on this project. The exe-Guard project was selected for award under DE-FOA-0000359 with CFDA number 81.122 to address Topic Area of Interest 4: Hardened platforms and Systems. The exe-Guard project developed an antivirus solution for control system embedded devices to prevent the execution of unauthorized code and maintain settings and configuration integrity. This project created a white list antivirus solution for control systems capable of running on embedded Linux® operating systems. White list antivirus methods allow only credible programs to run through the use of digital signatures and hash functions. Once a system’s secure state is baselined, white list antivirus software denies deviations from that state because of the installation of malicious code as this changes hash results. Black list antivirus software has been effective in traditional IT environments but has negative implications for control systems. Black list antivirus uses pattern matching and behavioral analysis to identify system threats while relying on regular updates to the signature file and recurrent system scanning. Black list antivirus is vulnerable to zero day exploits which have not yet been incorporated into a signature file update. System scans hamper the performance of high availability applications, as revealed in NIST special publication 1058 which summarizes the impact of blacklist antivirus on control systems: Manual or “on-demand” scanning has a major effect on control processes in that they take CPU time needed by the control process (Sometimes close to 100% of CPU time). Minimizing the antivirus software throttle setting will reduce but not eliminate this effect. Signature updates can also take up to 100% of CPU time, but for a much shorter period than a typical manual scanning process. Control systems are vulnerable to performance losses if off-the-shelf blacklist antivirus solutions aren’t implemented with care. This investment in configuration in addition to constant decommissioning to perform manual signature file updates is unprecedented and impractical. Additionally, control systems are often disconnected or islanded from the network making the delivery of signature updates difficult. Exe-Guard project developed a white list antivirus solution that mitigated the above drawbacks and allows control systems to cost-effectively apply malware protection while maintaining high reliability. The application of security patches can also be minimized since white listing maintains constant defense against unauthorized code execution. Security patches can instead be applied in less frequent intervals where system decommissioning can be scheduled and planned for. Since control systems are less dynamic than IT environments, the feasibility of maintaining a secure baselined state is more practical. Because upgrades are performed in infrequent, calculated intervals, it allows a new security baseline to be established before the system is returned to service. Exe-Guard built on the efforts of SNL under the Code Seal project. SNL demonstrated prototype Trust Anchors on the project which are independent monitoring and control devices that can be integrated into untrustworthy components. The exe-Guard team started with the lessons learned under this project then designed commercial solution for white list malware protection. Malware is a real threat, even on islanded or un-networked installations, since operators can unintentionally install infected files, plug in infected mass storage devices, or infect a piece of equipment on the islanded local area network that can then spread to other connected equipment. Protection at the device level is one of the last layers of defense in a security-in-depth defense model before an asset becomes compromised. This project provided non-destructive intrusion, isolation and automated response solution, achieving a goal of the Department of Energy (DOE) Roadmap to Secure Control Systems. It also addressed CIP-007-R4 which requires asset owners to employ malicious software prevention tools on assets within the electronic security perimeter. In addition, the CIP-007-R3 requirement for security patch management is minimized because white listing narrows the impact of vulnerabilities and patch releases. The exe-Guard Project completed all tasks identified in the statement of project objective and identified additional tasks within scope that were performed and completed within the original budget. The cost share was met and all deliverables were successfully completed and submitted on time. Most importantly the technology developed and commercialized under this project has been adopted by the Energy sector and thousands of devices with exe-Guard technology integrated in them have now been deployed and are protecting our power systems today

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