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DOE OSTI2017

Global reverse supply chain design for solid waste recycling under uncertainties and carbon emission constraint

Highlights: • We propose a robust model for global reverse supply chain design. • The uncertain waste collection rate, currency exchange rate, and the maritime cost are incorporated. • The total emission and cost are affected by both the uncertainties and the global carbon cap. • The waste products flows between countries vary with the levels of uncertainties and the global carbon cap. • There is an opportunity to reduce the maritime emission. - Abstract: The emergence of concerns over environmental protection, resource conservation as well as the development of logistics operations and manufacturing technology has led several countries to implement formal collection and recycling systems of solid waste. Such recycling system has the benefits of reducing environmental pollution, boosting the economy by creating new jobs, and generating income from trading the recyclable materials. This leads to the formation of a global reverse supply chain (GRSC) of solid waste. In this paper, we investigate the design of such a GRSC with a special emphasis on three aspects; (1) uncertainty of waste collection levels, (2) associated carbon emissions, and (3) challenges posed by the supply chain’s global aspect, particularly the maritime transportation costs and currency exchange rates. To the best of our knowledge, this paper is the first attempt to integrate the three above-mentioned important aspects in the design of a GRSC. We have used mixed integer-linear programming method along with robust optimization to develop the model which is validated using a sample case study of e-waste management. Our results show that using a robust model by taking the complex interactions characterizing global reverse supply chain networks into account, we can create a better GRSC. The effect of uncertainties and carbon constraints on decisions to reduce costs and emissions are also shown.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2012

Adaptive planning using megavoltage fan-beam CT for radiation therapy with testicular shielding

This study highlights the use of adaptive planning to accommodate testicular shielding in helical tomotherapy for malignancies of the proximal thigh. Two cases of young men with large soft tissue sarcomas of the proximal thigh are presented. After multidisciplinary evaluation, preoperative radiation therapy was recommended. Both patients were referred for sperm banking and lead shields were used to minimize testicular dose during radiation therapy. To minimize imaging artifacts, kilovoltage CT (kVCT) treatment planning was conducted without shielding. Generous hypothetical contours were generated on each 'planning scan' to estimate the location of the lead shield and generate a directionally blocked helical tomotherapy plan. To ensure the accuracy of each plan, megavoltage fan-beam CT (MVCT) scans were obtained at the first treatment and adaptive planning was performed to account for lead shield placement. Two important regions of interest in these cases were femurs and femoral heads. During adaptive planning for the first patient, it was observed that the virtual lead shield contour on kVCT planning images was significantly larger than the actual lead shield used for treatment. However, for the second patient, it was noted that the size of the virtual lead shield contoured on the kVCT image was significantly smaller than the actual shield size. Thus, new adaptive plans based on MVCT images were generated and used for treatment. The planning target volume was underdosed up to 2% and had higher maximum doses without adaptive planning. In conclusion, the treatment of the upper thigh, particularly in young men, presents several clinical challenges, including preservation of gonadal function. In such circumstances, adaptive planning using MVCT can ensure accurate dose delivery even in the presence of high-density testicular shields.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2014

MO-B-16A-02: In Memoriam of Donald D. Tolbert: Surviving the Politics of Radiation Therapy

Today's healthcare work environment is ever-changing and without a doubt will continue to do so for the foreseeable future. How physicists are employed, evaluated, and valued are important aspects of our careers. With increasing demands and challenges being placed on the medical physics workforce, it is important to have the skills and knowledge to prepare for potential challenges to the status-quo of our employment status. Surviving in a world of change, consolidation, increased workload, and financial constraints is not a given, and preparing for those changes and challenges will benefit individuals as well as the medical physics community at large. Learning Objectives: Understand the challenges of succeeding in different work environments. Learn strategies to help define the role of a medical physicist to various administrators, physicians, and department staff and directors. Learn how to successfully communicate and interact with University, Hospital, and Department administrators.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2023

Interface Specifications for RAdiation Portal Technology Enhancement & Replacement (RAPTER) Modules

Radiation Portal Monitors (RPMs) were deployed throughout the port and border infrastructure of the United States (U.S.) beginning in 2003 to monitor for the possible presence of uncontrolled radiological and nuclear materials. Since that time, the U.S. Government (USG) has learned much about the operational challenges faced in the field. Principal among the shortcomings has been the lack of flexibility afforded the USG when all Internet Protocol (IP) rights and interfaces of the system are owned by the Original Equipment Manufacturer (OEM).

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

DOE OSTI2024

AI for Nuclear Safeguards Verification

The International Atomic Energy Agency (IAEA) utilizes AI/ML to analyze open-source information, including satellite imagery and scientific publications, to verify the completeness of State declarations regarding nuclear activities. AI/ML already assist the IAEA with automating processes and analysis of large datasets, including satellite imagery and unstructured data, improving efficiency and effectiveness of safeguards implementation. AI/ML in nuclear safeguards come with its own challenges that include the need for large, unbiased datasets, the risk of AI-generated fake information, including the potential for manipulation of satellite imagery.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2025

A Novel Optical Instrument for On-Line Measurement of Particle Size Distribution—Application to Clean Coal Technologies

A flow cell is a critical measurement interface for many optical instruments. However, the flows are often sampled under harsh conditions, such as under high pressure and/or high temperature, in the presence of particles, moisture, vapors with high dew points or corrosive gases. Therefore, obtaining a high-optical-quality flow cell that does not perturb the measurement is a significant challenge. To address this challenge, we proposed a new flow cell that employs a unique laminar coaxial flow field (for the purge and sample flows). A test system was built to conduct particle size distribution (PSD) measurements with no sampling bias using a state-of-the-art analyzer (Malvern Panalytical Insitec). The results revealed that the measurement zone is well defined solely by the sample flow, and the optical windows are well protected by the purge flow, with minimal risk of any depositions from the sample flow. Using this flow cell, the Insitec can successfully measure PSD under high pressure and temperature under moist, corrosive conditions without generating any sampling bias. Importantly, we successfully applied this flow cell for on-line PSD measurement for the flue gas of a 100 kWth pressurized oxy-coal combustor operating at 15 bara.

Cheng, Mao (ORCID:0000000213273900)↗

DOE OSTI2017

Challenges to Collection of High Quality Samples of Saltstone - 17468

The Savannah River Site (SRS) Saltstone Disposal Facility (SDF) is used to dispose of low-level radioactive liquid waste in the form of grout. The SDF is comprised of a series of concrete saltstone disposal units (SDUs) that receive the grout. The grout solidifies into a cementitious waste form known as saltstone. Properties of saltstone that influence contaminant release have been measured on simulant material but not on samples of emplaced saltstone because samples of emplaced radioactive saltstone are difficult to obtain, transport, and store in a manner that protects the properties of interest. Savannah River Remediation (SRR) initiated a project to obtain samples of emplaced saltstone such that the two critical properties, hydraulic conductivity and reduction capacity, are negligibly impacted by the sample collection effort. The sample collection project was established to manage sample collection efforts beginning with sample collection mock-up activities through field execution. The project focused on three phases: mock-up in a clean environment, development of equipment needed to maintain an inert environment during sample transport and laboratory storage, and coordination of Facility operations and support resources and schedules to support sample collection. A mock-up facility was constructed at SRS to mimic the SDU. Core drill equipment was tested, procedures developed, and operator training conducted using the mockup facility. Concurrent with mock-up activities, inert transportation and storage equipment was designed, manufactured, tested, and specific operating instruction included in the sample collection procedure. Inerting equipment minimized oxidation from the atmosphere as the samples were removed from the disposal unit, transported, and stored in the laboratory awaiting analysis. Coordination with the Saltstone Facility began during construction of the mock-up platform to collect current as-built information for platform construction. Baseline data was collected from the disposal unit vapor space to assess the potential for personnel exposure from chemical hazards associated with trapped vapors. Based on this data, mitigating actions were incorporated into the project scope. Finally, project and facility schedules were integrated to assure that facility non-processing windows, support personnel, equipment fabrication, and field preparation activities were in alignment and supportive of the overall sample collection objectives. During May 2014, 485 linear cm of approximately 5 cm diameter radioactive core material was successfully collected from three access ports in SDU Cell 2A, inerted, transported to the laboratory, and stored in an inert environment for analysis. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2015

MO-DE-BRA-01: Enhancing Radiation Physics Instruction Through Gamification and E-Learning

Purpose: This project sought to “gamify” the instruction of radiation interaction physics concepts for technology students. Gamification applies game mechanics and user interactions in active learning contexts. In one part of this project, a self-guided eModule was developed for conceptual radiation interaction instruction. In a second part, a web-based game, Particle Launch (http://particle-launcher.ist.unomaha.edu), was created to challenge students to quickly apply radiation interaction concepts in a way that is stimulating and motivating. Methods: The eModule, focused on conceptual interaction physics, was designed in Adobe Captivate and incorporates animation, web videos, and assessment questions in order to generate student interest. Navigating the whole module takes 40 minutes for beginners. Assessments after three main sections are comprised of 3–4 questions randomly selected from a question pool. In collaboration with the University of Nebraska at Omaha’s College of Information Science and Technology, the Particle Launch game was created with the Unity gaming engine and designed with a game-play look and feel. The object of the game is to utilize different particles, energies, and directions to destroy a target given a limited number of resources and time to complete the task. A rewards system encourages accurate shots. Results: The eModule part of the project encourages a flipped classroom model in which class time is devoted to application of concepts rather than information-based lectures. Currently, eModule assessments are not tracked but this feature could be incorporated to encourage participation. Furthermore, in a class of five technology students, the game was found to be fun and engaging and had the effect of reinforcing basic concepts from the eModule. Conclusion: Gamification has significant potential to alter medical physics instruction. Game-play feedback is an important part of the learning process. Students found Particle Launch inviting and challenging and further research could help game design. This project was generously supported by the Office of the Vice-Chancellor for Academic Affairs and the University of Nebraska Medical Center.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2016

Interfacial behaviours between lithium ion conductors and electrode materials in various battery systems

In recent years room temperature Li+ ion conductors have been intensively revisited in order to develop safe lithium ion (Li-ion) batteries and beyond that can be deployed in the electrical vehicles. Through careful modification on materials synthesis, promising solid Li+ conductors with high ionic conductivity, competitve with liquid electrolytes, have been demonstrated. However, the integration of those highly conductive solid electrolytes into the whole system is still very challenging mainly due to the high impedance existing in the different interfaces throughout the entire battery structure. Herein , this review paper focuses on the overview of the interfacial behaviors between Li+ conductors and cathode/anode materials. The origin, evolution and potential solutions to reuce these interfacial impedances are reviewed for various battery systems spanning from Li-ion, lithium sulfur (Li-S), lithium oxygen (Li-O2) batteries to lithium metal protection. The predicted gravimetric and volumetric energy densities at different scenarios are also discussed along with the prospectives for further development of solid state batteries.

Wu, Bingbin↗

DOE OSTI2017

Speciation of Soil Phosphorus Assessed by XANES Spectroscopy at Different Spatial Scales

Precise management of soil phosphorus (P) to meet competing demands of agriculture and environmental protection can benefit from more comprehensive characterization of P speciation in soils. Our objectives were to provide spatial context for spectroscopic analyses of soil P speciation in relation to molecular-scale species and landscape-scale management of P, and to compare soil P-species diversity from spectroscopic measurements at submicron and millimeter scales. The spatial range of ~26 orders of magnitude between atomic and field scales presents a challenge to upscaling and downscaling information from spectroscopic analyses of soils. Scanning fluorescence X-ray microscopy images of a 50-mm ´ 45-mm area of an organic soil sample showed heterogeneous distributions of P, Al, and Si. Microscale X-ray absorption near edge structure (μ-XANES) spectra collected at the P K-edge from 12 spots on the soil sample exhibited diverse features that indicated variations in highly localized P speciation. Linear combination fitting analysis of the μ-XANES spectra included various proportions of three standards that appeared in fits for most spots and five standards that appeared in fits for one spot each. The fit to a bulk-soil spectrum was dominated by two of the common standards in the μ-XANES fits, and a fit to the sum of m-XANES spectra included four of the standards. Lastly, these results illustrate a gain in P species sensitivity from spatially resolved XANES analysis. Integrating spectroscopic analyses from multiple scales determines soil P species diversity and will ultimately help connect speciation to the chemical reactivity and mobility of P in soils.

36 MATERIALS SCIENCE↗

DOE OSTI2017

Anion-Regulated Selective Generation of Cobalt Sites in Carbon: Toward Superior Bifunctional Electrocatalysis

We report the introduction of active transition metal sites (TMSs) in carbon enables the synthesis of noble-metal-free electrocatalysts for clean energy conversion applications, however, there are often multiple existing forms of TMSs, which are of different natures and catalytic models. Regulating the evolution of distinctive TMSs is highly desirable but remains challenging to date. Anions, as essential elements involved in the synthesis, have been totally neglected previously in the construction of TMSs. Herein, the effects of anions on the creation of different types of TMSs is investigated for the first time. It is found that the active cobalt-nitrogen sites tend to be selectively constructed on the surface of N-doped carbon by using chloride, while metallic cobalt nanoparticles encased in protective graphite layers are the dominant forms of cobalt species with nitrate ions. The obtained catalysts demonstrate cobalt-sites-dependent activity for ORR and HER in acidic media. And the remarkably enhanced catalytic activities approaching that of benchmark Pt/C in acidic medium has been obtained on the catalyst dominated with cobalt-nitrogen sites, confirmed by the advanced spectroscopic . In conclusion, our finding demonstrates a general paradigm of anion-regulated evolution of distinctive TMSs, providing a new pathway for enhancing performances of various targeted reactions related with TMSs.

36 MATERIALS SCIENCE↗

DOE OSTI2016

Combined virus-like particle and fusion protein-encoding DNA vaccination of cotton rats induces protection against respiratory syncytial virus without causing vaccine-enhanced disease

A safe and effective vaccine against respiratory syncytial virus (RSV) should confer protection without causing vaccine-enhanced disease. Here, using a cotton rat model, we investigated the protective efficacy and safety of an RSV combination vaccine composed of F-encoding plasmid DNA and virus-like particles containing RSV fusion (F) and attachment (G) glycoproteins (FFG-VLP). Cotton rats with FFG-VLP vaccination controlled lung viral replication below the detection limit, and effectively induced neutralizing activity and antibody-secreting cell responses. In comparison with formalin inactivated RSV (FI-RSV) causing severe RSV disease after challenge, FFG-VLP vaccination did not cause weight loss, airway hyper-responsiveness, IL-4 cytokines, histopathology, and infiltrates of proinflammatory cells such as eosinophils. FFG-VLP was even more effective in preventing RSV-induced pulmonary inflammation than live RSV infections. This study provides evidence that FFG-VLP can be developed into a safe and effective RSV vaccine candidate. - Highlights: • Combined RSV FFG VLP vaccine is effective in inducing F specific responses. • FFG VLP vaccine confers RSV neutralizing activity and viral control in cotton rats. • Cotton rats with RSV FFG VLP vaccination do not show vaccine-enhanced disease. • Cotton rats with FFG VLP vaccine induce F specific antibody secreting cell responses. • Cotton rats with FFG VLP do not induce lung cellular infiltrates and Th2 cytokine.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2020

Cooperative Load Scheduling for Multiple Aggregators Using Hierarchical ADMM

Demand response (DR) serves an important role in improving the efficiency and stability of power systems. In recent years, with advances in communication and smart device technologies, many aggregators have emerged to facilitate end customer participation in DR programs. These aggregators, equipped with customized optimal control algorithms, are capable of providing various grid services. Among them is load scheduling during DR events, namely following a load signal provided by the utility company while minimizing overall customer discomfort. However, as the number of aggregators keeps increasing, it becomes challenging for utility companies to conduct load scheduling for multiple aggregators and generate reference signals for each of them. This paper proposes an optimization framework using hierarchical alternating direction method of multipliers (H-ADMM) to optimally generate load following signals for multiple aggregators. Under this framework, utility and multiple aggregators work in a cooperative manner, aiming at minimizing an overall system cost from different levels of the power system hierarchy, while protecting user privacy. A case study has been conducted in a system with multiple aggregators, based on control of HVAC loads. Experimental results validate the effectiveness of the proposed algorithm.

ADMM↗

DOE OSTI2015

MO-C-BRB-00: President’s Symposium: Revitalizing Scientific Excellence: Turning Research Into Clinical Reality Through Translational Research

Diagnostic radiology and radiation oncology are arguably two of the most technologically advanced specialties in medicine. The imaging and radiation medicine technologies in clinical use today have been continuously improved through new advances made in the commercial and academic research arenas. This symposium explores the translational path from research through clinical implementation. Dr. Pettigrew will start this discussion by sharing his perspectives as director of the National Institute of Biomedical Imaging and Bioengineering (NIBIB). The NIBIB has focused on promoting research that is technological in nature and has high clinical impact. We are in the age of precision medicine, and the technological innovations and quantitative tools developed by engineers and physicists working with physicians are providing innovative tools that increase precision and improve outcomes in health care. NIBIB funded grants lead to a very high patenting rate (per grant dollar), and these patents have higher citation rates by other patents, suggesting greater clinical impact, as well. Two examples of clinical translation resulting from NIH-funded research will be presented, in radiation therapy and diagnostic imaging. Dr. Yu will describe a stereotactic radiotherapy device developed in his laboratory that is designed for treating breast cancer with the patient in the prone position. It uses 36 rotating Cobalt-60 sources positioned in an annular geometry to focus the radiation beam at the system’s isocenter. The radiation dose is delivered throughout the target volume in the breast by constantly moving the patient in a planned trajectory relative to the fixed isocenter. With this technique, the focal spot dynamically paints the dose distribution throughout the target volume in three dimensions. Dr. Jackson will conclude this symposium by describing the RSNA Quantitative Imaging Biomarkers Alliance (QIBA), which is funded in part by NIBIB and is a synergistic collaboration between medical physicists, radiologists, oncologists, industry representatives, and other stakeholders. The mission of QIBA is to improve the accuracy and practicality of quantitative image-based biomarkers by increasing precision across devices, patients, and time, an essential step in incorporating quantitative imaging biomarkers into radiology practice. Validated quantitative imaging biomarkers are necessary to support precision medicine initiatives, multimodality / multiparametric applications in medicine, treatment planning and response assessment, and radiogenomics applications. Current applications in the QIBA portfolio extend to cancer diagnosis and treatment, pulmonary diseases, and neurological disorders. The overall goal of this symposium is to illustrate the bidirectional exchange between medical research and clinical practice. Revitalizing scientific excellence in clinical medical physics challenges practitioners to identify clinical limitations, which then drive research innovation; research funded by the NIH and other agencies develops technological solutions to these limitations, which are translated to the care environment to ultimately improve clinical practice in radiology and radiation oncology.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

MO-DE-207-04: Imaging educational program on solutions to common pediatric imaging challenges

This imaging educational program will focus on solutions to common pediatric imaging challenges. The speakers will present collective knowledge on best practices in pediatric imaging from their experience at dedicated children’s hospitals. The educational program will begin with a detailed discussion of the optimal configuration of fluoroscopes for general pediatric procedures. Following this introduction will be a focused discussion on the utility of Dual Energy CT for imaging children. The third lecture will address the substantial challenge of obtaining consistent image post -processing in pediatric digital radiography. The fourth and final lecture will address best practices in pediatric MRI including a discussion of ancillary methods to reduce sedation and anesthesia rates. Learning Objectives: To learn techniques for optimizing radiation dose and image quality in pediatric fluoroscopy To become familiar with the unique challenges and applications of Dual Energy CT in pediatric imaging To learn solutions for consistent post-processing quality in pediatric digital radiography To understand the key components of an effective MRI safety and quality program for the pediatric practice.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2016

MO-A-201-00: A Cliff’s Notes Version of Proton Therapy

Proton therapy is a rapidly growing modality in the fight against cancer. From a high-level perspective the process of proton therapy is identical to x-ray based external beam radiotherapy. However, this course is meant to illustrate for x-ray physicists the many differences between x-ray and proton based practices. Unlike in x-ray therapy, proton dose calculations use CT Hounsfield Units (HU) to determine proton stopping power and calculate the range of a beam in a patient. Errors in stopping power dominate the dosimetric uncertainty in the beam direction, while variations in patient position determine uncertainties orthogonal to the beam path. Mismatches between geometric and range errors lead to asymmetric uncertainties, and so while geometric uncertainties in x-ray therapy are mitigated through the use of a Planning Target Volume (PTV), this approach is not suitable for proton therapy. Robust treatment planning and evaluation are critical in proton therapy, and will be discussed in this course. Predicting the biological effect of a proton dose distribution within a patient is also a complex undertaking. The proton therapy community has generally regarded the Radiobiological Effectiveness (RBE) of a proton beam to be 1.1 everywhere in the patient, but there are increasing data to suggest that the RBE probably climbs higher than 1.1 near the end of a proton beam when the energy deposition density increases. This lecture will discuss the evidence for variable RBE in proton therapy and describe how this is incorporated into current proton treatment planning strategies. Finally, there are unique challenges presented by the delivery process of proton therapy. Many modern systems use a spot scanning technique which has several advantages over earlier scattered beam designs. However, the time dependence of the dose deposition leads to greater concern with organ motion than with scattered protons or x-rays. Image guidance techniques in proton therapy may also differ from standard x-ray approaches, due to equipment design or the desire to maximize efficiency within a high-cost proton therapy treatment room. Differences between x-ray and proton therapy delivery will be described. Learning Objectives: Understand how CT HU are calibrated to provide proton stopping power, and the sources of uncertainty in this process. Understand why a PTV is not suitable for proton therapy, and how robust treatment planning and evaluation are used to mitigate uncertainties. Understand the source and implications of variable RBE in proton therapy Learn about proton specific challenges and approaches in beam delivery and image guidance Jon Kruse has a research grant from Varian Medical Systems related to proton therapy treatment plannning.; J. Kruse, Jon Kruse has a research grant with Varian Medical Systems related to proton therapy planning.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2016

TH-D-BRC-00: Educational Point Counter/Point: Has Photon RT Hit the Limits?

Interest in proton therapy has increased dramatically in the past couple of years, especially in the United States. There certainly is an important place for proton therapy in the arsenal of cancer treatments. Its dosimetric advantage and potential for low toxicity makes it the perfect partner for photons and other cancer treatment modalities. Often there is a belief that the new technology ought to be better but many believe that they should be widely adopted in the clinic only after evidence has shown that they are at least as safe and efficacious as existing technologies, which are often less expensive. This is the case for proton radiotherapy. This session being both educational and debate will provide a good review of basics and technological advancement as well as a comprehensive clinical update for both proton and photon therapy. Future technology developments and how they will impact the potential dosimetric advantage of proton therapy will be discussed. Particularly the debate will focus on whether these developments will close or widen the gap between photon and proton therapy. Learning Objectives: To review challenges, limitations, and recent and future developments in proton therapy. To review challenges, limitations, recent and future developments in photon radiotherapy. To review current clinical trials and challenging clinical cases. C. Yu, No company or organization that my presentation mentions provided me with financial support. I am the Founder and CEO of Xcision Medical Systems, LLC. However, my presentation will not mention any product or technology developed by Xcision.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2020

Impact of multimode range and location on urban fuel economy on a light-duty spark-ignition based powertrain using vehicle system simulations

Multimode engine operation uses two or more combustion modes to maximize engine efficiency across the operational range of a vehicle to achieve higher overall vehicle fuel economy than is possible with a single combustion mode. More specifically for this study, multimode solutions are explored that make use of boosted SI under high load operation and other advanced combustion modes such as advanced compression ignition (ACI) under part-load conditions to enable additional engine efficiency improvements across a broader range of the engine operating map. ACI combustion has well-documented potential to improve efficiency and emissions under part-load operation but poses challenges that limit full engine speed-load range. This study investigates the potential impact of ACI operational range on simulated fuel economy to help focus research on areas with the most opportunity for improving fuel economy. These simulations make use of a vehicle model, discretized engine data, and employ a systematic exploration of ACI operational range to estimate multimode fuel economy for a mid-size passenger vehicle over U.S. Environmental Protection Agency’s Urban Dynamometer Driving Schedule. The results of this study highlight operational ranges with the highest potential fuel economy and correspondingly areas of focus for multimode research and ACI engine operation1.

Curran, Scott↗