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DOE OSTI2012

Semantic Information Modeling for Emerging Applications in Smart Grid

Smart Grid modernizes power grid by integrating digital and information technologies. Millions of smart meters, intelligent appliances and communication infrastructures are under deployment allowing advanced IT applications to be developed to secure and manage power grid operations. Demand response (DR) is one such emerging application to optimize electricity demand by curtailing/shifting power load when peak load occurs. Existing DR approaches are mostly based on static plans such as pricing policies and load shedding schedules. However, improvements to power management applications rely on data emanating from existing and new information sources with the growth of Smart Grid information space. In particular, dynamic DR algorithms depend on information from smart meters that report interval-based power consumption measurement, HVAC systems that monitor buildings heat and humidity, and even weather forecast services. In order for emerging Smart Grid applications to take advantage of the diverse data influx, extensible information integration is required. In this paper, we develop an integrated Smart Grid information model using Semantic Web techniques and present case studies of using semantic information for dynamic DR. We show the semantic model facilitates information integration and knowledge representation for developing the next generation Smart Grid applications.

complex event processing↗

DOE OSTI2017

Apply or Die: On the Role and Assessment of Application Papers in Visualization

Application-oriented papers provide an important way to invigorate and cross-pollinate the visualization field, but the exact criteria for judging an application paper's merit remain an open question. This article builds on a panel at the 2016 IEEE Visualization Conference entitled "Application Papers: What Are They, and How Should They Be Evaluated?" that sought to gain a better understanding of prevalent views in the visualization community. This article surveys current trends that favor application papers, reviews the benefits and contributions of this paper type, and discusses their assessment in the review process. It concludes with recommendations to ensure that the visualization community is more inclusive to application papers.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2014

Fast Demand Forecast of Electric Vehicle Charging Stations for Cell Phone Application

This paper describes the core cellphone application algorithm which has been implemented for the prediction of energy consumption at Electric Vehicle (EV) Charging Stations at UCLA. For this interactive user application, the total time of accessing database, processing the data and making the prediction, needs to be within a few seconds. We analyze four relatively fast Machine Learning based time series prediction algorithms for our prediction engine: Historical Average, kNearest Neighbor, Weighted k-Nearest Neighbor, and Lazy Learning. The Nearest Neighbor algorithm (k Nearest Neighbor with k=1) shows better performance and is selected to be the prediction algorithm implemented for the cellphone application. Two applications have been designed on top of the prediction algorithm: one predicts the expected available energy at the station and the other one predicts the expected charging finishing time. The total time, including accessing the database, data processing, and prediction is about one second for both applications.

Majidpour, Mostafa↗

DOE OSTI2021

An Application for Validation of Power Distribution System Models in an ADMS Environment

An accurate model of a power distribution system is the foundation for model-based applications that ensure efficient and reliable grid operation in an advanced distribution management system (ADMS) environment. However, these models are error-prone and comprehensive model validation is challenging due to lack of standards-based systems, data originating from disparate databases and other sources, and the constantly evolving nature of modern power distribution systems. In this paper, a novel framework for comprehensive model validation is described. The proposed application, the Model Validator, ensures that a model is both consistent and feasible by validating the derivative static and operational network model. A modular architecture for the application has been implemented and integrated with an open-source standards-based platform for ADMS application development, GridAPPS-D, allowing new validation capability to be added with minimal time and effort. The Model Validator application is demonstrated on the IEEE 13-bus, 123-bus, and 8500-node test cases over three validation scenarios.

Poudel, Shiva↗

DOE OSTI2016

Pellet Injection Technology and Its Applications on ITER

Cryogenic pellet injectors for use in fusion research have been under development at Oak Ridge National Laboratory for over 30 years. The original application of the technology was to add fuel to magnetically confined plasmas to replace D-T ions that are consumed in the fusion reactions or lost due to transport out of the confining magnetic fields. This application is still the primary use for pellet injection and is planned for implementation on the ITER burning plasma experiment. More recently, there have been additional applications for the injection of cryogenic pellets in the areas of disruption and edge-localized mode mitigation. Injectors for these applications are also being implemented for ITER, which require refinements of the technology for production and shattering of very large pellets and production of very small high repetition rate pellets, respectively. Details of these applications and injection system designs are presented.

Baylor, Larry R.↗

DOE OSTI2022

Superconducting Shuttle-Flux Shift Register for Race Logic and Its Applications

Here this paper presents a superconducting, magnetically-coupled, shuttle-flux shift register (SF-SR) that stores single flux quantum (SFQ) pulses. This shift register has a DC bias operating margin of ±34% at 10 GHz, with a power dissipation of 3.6 μW and 38% fewer Josephson junctions (JJs) when scaled up to multiple stages compared to a data flip-flop (DFF) based shift register. The clock input is inductively coupled and is independent from the data input. We then present three applications for our SF-SR. In the first application, we add two non-destructive readout (NDRO) cells to construct a buffer that temporarily stores the temporal information of a series of race logic (RL) pulses. The second application is a pseudo-random number generator based on a linear function shift register (LFSR). The third application is N parallel SF-SRs that can act similar to a deserializer or instead can emulate a single SF-SR of N times higher clock frequency. These three applications motivate deep shift registers with many shifting intervals, which our SF-SR can implement with fewer JJs and lower power consumption compared to DFF-based shift registers.

42 ENGINEERING↗

DOE OSTI2020

Evaluation and Demonstration of Blockchain Applicability Framework

Blockchain technology has been gaining great interest from a variety of industry sectors, including financial, food processing, and power and energy markets. Realizing the strength of blockchain technology beyond the successful application in the cryptocurrency arena, researchers have been evaluating and using blockchain for applications such as supply chain management, transactive industry (both financial and energy), system integrity, device cybersecurity, identity management, and much more. One of the unique elements of the blockchain technology that made it such a captivating technology to researchers is its plethora of features. Some of the features include smart contracts, cryptocurrency and tokenizing, immutable distributed ledger, cryptographic hashing, and digital signature. In addition, there are multiple types of blockchains, such as permissioned/private and permissionless/public, and various consensus models, such as proof-of-work, proof-of-authority, proof-of-burn, and proof-of-stake. Therefore, it is often non-trivial to determine if an application requires a blockchain. If so, what kind of blockchain and consensus is most appropriate? This paper discusses the blockchain applicability framework (BAF), which was specifically designed with the purpose to answer those questions. BAF is divided into five domains, 18 subdomains, and about 100 controls. It is designed to ingest detailed user requirements to perform a weighted evaluation that is built on mathematical constructs to determine the ideal combination of blockchain that is appropriate for an application. Along with the core logical formulation of BAF, this paper depicts the efficacy of BAF through two use cases

Gourisetti, Sri Nikhil G.↗

DOE OSTI2018

Profiling and Predicting Application Performance on the Cloud

Cloud providers continue to expand and diversify their collection of leasable resources to meet the needs of an increasingly wide range of applications. While this flexibility is a key benefit of the cloud, it also creates a complex landscape in which users are faced with many resource choices for a given application. Suboptimal selections can both degrade performance and increase costs. Given the rapidly evolving pool of resources, it is infeasible for users alone to select instance types; instead, automated methods are needed to simplify and guide resource provisioning. Here we present a method for the automatic prediction of application performance on arbitrary cloud instances. We combine offline and online profiling approaches, using historical data gathered from non-cloud environments and targeted profiling runs on cloud environments to create a composite application model that can predict run times on a given cloud instance type for a given input data size. We demonstrate average error of 17.2% across nine applications used in production bioinformatics workflows. Finally, we evaluate an experiment design approach to explore the trade-off between the cost of profiling and the accuracy of our models. Using this approach, with no prior knowledge, we show that using 4 selectively chosen experiments we can achieve performance within 30% of a model trained using all instance types.

Cloud profiling↗

DOE OSTI2017

Applicability Analysis of Validation Evidence for Biomedical Computational Models

Computational modeling has the potential to revolutionize medicine the way it transformed engineering. However, despite decades of work, there has only been limited progress to successfully translate modeling research to patient care. One major difficulty which often occurs with biomedical computational models is an inability to perform validation in a setting that closely resembles how the model will be used. For example, for a biomedical model that makes in vivo clinically relevant predictions, direct validation of predictions may be impossible for ethical, technological, or financial reasons. Unavoidable limitations inherent to the validation process lead to challenges in evaluating the credibility of biomedical model predictions. Therefore, when evaluating biomedical models, it is critical to rigorously assess applicability, that is, the relevance of the computational model, and its validation evidence to the proposed context of use (COU). However, there are no well-established methods for assessing applicability. In this paper, we present a novel framework for performing applicability analysis and demonstrate its use with a medical device computational model. The framework provides a systematic, step-by-step method for breaking down the broad question of applicability into a series of focused questions, which may be addressed using supporting evidence and subject matter expertise. The framework can be used for model justification, model assessment, and validation planning. While motivated by biomedical models, it is relevant to a broad range of disciplines and underlying physics. Finally, the proposed applicability framework could help overcome some of the barriers inherent to validation of, and aid clinical implementation of, biomedical models.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2014

SU-E-T-560: Commissioning An HDR Freiburg Flap Applicator for Skin Lesion Treatment

Purpose: Flexible Freiburg flap used with high dose rate afterloaders is easy to cut into any size for any body site and to dwell with a precise source position, conforms to curved skin surface and then to the planned target. However, unlike intracavity or interstitial situations, incomplete scatter environment due to flap applicators exposed to air might lead to dose difference between the delivered and planned. This research is focused on the dose deviation of incomplete scatter versus full scatter. Methods: A 12x12 cm of Freiburg flap applicator was used for the validation. A Nucletron Oncentra Brachy Ver. 4.3 treatment planning system (TPS) was used for treatment planning. However, no heterogeneity correction incorporated into the brachytherap TPS needs to be considered. A Philips Brilliance CT Big Bore was employed for CT scan. Radiation was delivered using a Nucletron HDR remote afterloader system. A 10cm bolus was used to cover the flap for obtaining a full scatter. An OSL, ion chamber, and Gafchromic EBT2 film were used for commissioning the flap applicator. Results: The applicator calibration at 5mm depth was performed using an OSL dosimeter. Applicator source dwelling positions with 1D and 2D array exposed to and recorded by Gafchromic EBT2 film showed an agreement within 1mm. 1D array of Freiburg flap exhibited 4.2% cooler in dose with incomplete scatter than full scatter. 2D array showed 7.1% lower in dose for incomplete scatter than full scatter. The deviation was found more than 10% beyond 8cm in depth. Conclusion: Significant dose deviation caused by the incomplete scatter environment was found to be 7.1% at 1cm depth. This deviation was increased with increasing depth. The inaccuracy resulted from the incomplete scatter can be fixed by either placing a bolus on the top of the flap or making the plan at least 7% hotter.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2015

SU-E-J-207: Effect of Pulse Sequence Parameters On Geometric Distortions Induced by a Titanium Brachytherapy Applicator

Purpose: To investigate the effect of readout bandwidth and voxel size on the appearance of distortion artifacts caused by a titanium brachytherapy applicator. Methods: An acrylic phantom was constructed to rigidly hold a MR conditional, titanium Fletcher-Suit-Delclos-style applicator set (Varian Medical Systems) for imaging on CT (Philips Brilliance) and 1.5T MRI (Siemens Magnetom Aera). Several variants of MRI parameters were tried for 2D T2-weighted turbo spin echo imaging in comparison against the standard clinical protocol with the criteria to keep relative SNR loss less than 20% and imaging time as short as possible. Two 3D sequences were also used for comparison with similar parameters. The applicator tandem was segmented on axial CT images (0.4×0.4×1.5mm {sup 3} resolution) and the CT images were registered to the 3D MR images in Eclipse (Varian). The applicator volume was then overlaid on all MRI sets in 3D-Slicer and distances were measured from the tandem tip to the MRI artifact edge in right/left/superior and anterior/posterior/superior directions from coronal and sagittal 2D acquisitions, respectively, or 3D data reformats. Artifact regions were also manually contoured in coronal/sagittal orientations for area measurements. Results: As would be expected, reductions in voxel size and increases in readout bandwidth reduced artifact size (average max artifact length decreased by 0.95 mm and average max area decrease by 0.27 cm{sup 2}). Interestingly, bandwidth increases yielded reductions in area (0.19 cm{sup 2}) and in distance measurements (1 mm) even with voxel increases, as compared to a standard protocol. This could be useful when high performance protocols are not feasible due to long imaging times. Conclusion: We have characterized artifacts caused by cervical brachytherapy applicator across multiple sequence parameters at 1.5T. Future work will focus on finalizing an optimal protocol that balances artifact reduction with imaging time and then testing this new protocol in patients.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

SU-E-J-216: A Sequence Independent Approach for Quantification of MR Image Deformations From Brachytherapy Applicators

Purpose: MRI is increasingly used as a single imaging modality for brachytherapy treatment planning. The presence of a brachytherapy applicator may cause distortions in the images, especially at higher field strengths. Our aim is to develop a procedure to quantify these distortions theoretically for any MR-sequence and to verify the estimated deformations for clinical sequences. Methods: Image distortions due to perturbation of the B0-field are proportional to the ratio of the induced frequency shift and the read-out bandwidth of the applied sequence. By reconstructing a frequency-shift map from the phase data from a multi-echo sequence, distortions can be calculated for any MR-sequence. Verification of this method for estimating distortions was performed by acquiring images with opposing read-out directions and consequently opposing distortions. The applicator shift can be determined by rigidly matching these images. Clinically, T2W-TSE-images are used for this purpose. For pre-clinical tests, EPI-sequences with narrow read-out bandwidth (19.5–47.5Hz), consequently large distortions, were added to the set of clinical MRsequences. To quantify deformations of the Utrecht Interstitial CT/MR applicator (Elekta Brachytherapy) on a Philips Ingenia 3T MRI, pre-clinical tests were performed in a phantom with the applicator in water, followed by clinical validation. Results: Deformations observed in the narrow bandwidth EPI-images were well predicted using the frequency-shift, the latter giving an overestimation up to 30%/up to 1 voxel. For clinically applied MR-sequences distortions were well below the voxel size. In patient setup distortions determined from the frequency-shift map were at sub-voxel level (<0.7mm). Using T2W-images larger distortions were found (1–2mm). This discrepancy was caused by patient movement between/during acquisition of the T2W-images with opposing read-out directions. Conclusion: Phantom experiments demonstrated the feasibility of a clinical procedure for quantification of MR-image distortions for any MR-sequence. In a clinical set-up the distortions from a Utrecht interstitial CT/MR applicator are sub-voxel level. This work was partially funded by Elekta Brachytherpy.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

SU-E-T-10: A Clinical Implementation and the Dosimetric Evidence in High Dose Rate Vaginal Multichannel Applicator Brachytherapy

Purpose: The multichannel cylindrical applicator has a distinctive modification of the traditional single channel cylindrical applicator. The novel multichannel applicator has additional peripheral channels that provide more flexibility both in treatment planning process and outcomes. To protect by reducing doses to adjacent organ at risk (OAR) while maintaining target coverage with inverse plan optimization are the goals for such novel Brachytherapy device. Through a series of comparison and analysis of reults in more than forty patients who received HDR Brachytherapy using multichannel vaginal applicator, this procedure has been implemented in our institution. Methods: Multichannel planning was CT image based. The CTV of 5mm vaginal cuff rind with prescribed length was well reconstructed as well as bladder and rectum. At least D95 of CTV coverage is 95% of prescribed dose. Multichannel inverse plan optimization algorithm not only shapes target dose cloud but set dose avoids to OAR’s exclusively. The doses of D2cc, D5cc and D5; volume of V2Gy in OAR’s were selected to compare with single channel results when sole central channel is only possibility. Results: Study demonstrates plan superiorly in OAR’s doe reduction in multi-channel plan. The D2cc of the rectum and bladder were showing a little lower for multichannel vs. single channel. The V2Gy of the rectum was 93.72% vs. 83.79% (p=0.007) for single channel vs. multichannel respectively. Absolute reduced mean dose of D5 by multichannel was 17 cGy (s.d.=6.4) and 44 cGy (s.d.=15.2) in bladder and rectum respectively. Conclusion: The optimization solution in multichannel was to maintain D95 CTV coverage while reducing the dose to OAR’s. Dosimetric advantage in sparing critical organs by using a multichannel applicator in HDR Brachytherapy treatment of the vaginal cuff is so promising and has been implemented clinically.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

SU-E-T-55: A Novel Applicator for High Dose Rate Brachytherapy Treatments of Ocular Conjunctiva

Purpose: To evaluate the clinical feasibility of IntraBeam intra operative kV irradiation beam device for ocular conjunctiva treatments. The Intra-Beam system offers a 4.4 mm diameter needle applicator, that is not suitable for treatment of a large surface with limits access. We propose an adaptor that will answer to this clinical need and provide initial dosimetry. Methods: The dose distribution of the needle applicator is non uniform and hence not suitable for treatment of relatively large surfaces. We designed an adapter to the needle applicator that will filter the X-rays and produce a conformal dose distribution over the treatment area while shielding surfaces to be spared. Dose distributions were simulated using FLUKA is a fully integrated particle physics Monte Carlo simulation package. Results: We designed a wedge applicator made of Polythermide window and stainless steel for collimating. We compare the dose distribution to that of the known needle and surface applicators. Conclusion: Initial dosimetry shows feasibility of this approach. While further refinements to the design may be warranted, the results support construction of a prototype and confirmation of the Monte Carlo dosimetry with measured data.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

SU-E-T-787: Utility of the Two Candidate 192-Ir and 169-Yb HDR Sources for Use with a Novel Direction Modulated Brachytherapy Tandem Applicator for Cervical Cancer Treatment

Purpose: A novel tungsten alloy shielded, MRI-compatible, direction modulated brachytherapy (DMBT) concept tandem applicator, which enables unprecedented intensity modulation, was used to evaluate treatment plan quality improvement over a conventional tandem. The utility of the 192-Ir and 169-Yb HDR sources, for use with the DMBT applicator, was evaluated. Methods: The total diameter of the DMBT tandem applicator is 6.0 mm, which consists of 5.4-mm diameter tungsten alloy and 0.3 mm thick plastic sheath. The tandem has 6 symmetric peripheral 1.3-mm diameter grooves for the source to travel. MCNPX v.2.6 was used to simulate the 192-Ir and 169-Yb sources inside the DMBT applicator. First, TG-43 source parameters were evaluated. Second, 3D dose matrix with 1 mm3 resolution were imported into an in-house-coded inverse optimization treatment planning program to obtain optimal plans for 19 clinical cases. All plans were compared with the standard tandem and ring plans. Prescription dose was 15.0 Gy. All plans were normalized to receive the same HRCTV D90. Results: Generally, the DMBT tandem (and ring) plans were better than the conventional tandem and ring plans for 192-Ir and 169-Yb HDR sources. The mean data of D2cc for bladder, rectum, and sigmoid were 11.65±2.30 Gy, 7.47±3.05 Gy, and 9.84±2.48 Gy for Ir-192 DMBT tandem, respectively. These data for Yb-169 were 11.67±2.26 Gy, 7.44±3.02 Gy, and 9.83±2.38 Gy, respectively. The HR-CTV D98 and V100 were 16.37±1.86 Gy and 97.37 ± 1.92 Gy for Ir-192 DMBT, respectively. The corresponding values for Yb-169 were 16.43±1.86 Gy, and 97.51 ± 1.91 Gy. Plans with the 169-Yb source generally produced more favorable results where V100 increased by 13.65% while D2cc across all OARs reduced by 0.54% compared with the 192-Ir plans. Conclusion: For the DMBT tandem applicator, 169-Yb source seems to produce more directional beams resulting in increased intensity modulation capacity, thus resulting in more conformal plans.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

SU-E-T-795: Validations of Dose Calculation Accuracy of Acuros BV in High-Dose-Rate (HDR) Brachytherapy with a Shielded Cylinder Applicator Using Monte Carlo Simulation

Purpose: Acuros BV has become available to perform accurate dose calculations in high-dose-rate (HDR) brachytherapy with phantom heterogeneity considered by solving the Boltzmann transport equation. In this work, we performed validation studies regarding the dose calculation accuracy of Acuros BV in cases with a shielded cylinder applicator using Monte Carlo (MC) simulations. Methods: Fifteen cases were considered in our studies, covering five different diameters of the applicator and three different shielding degrees. For each case, a digital phantom was created in Varian BrachyVision with the cylinder applicator inserted in the middle of a large water phantom. A treatment plan with eight dwell positions was generated for these fifteen cases. Dose calculations were performed with Acuros BV. We then generated a voxelized phantom of the same geometry, and the materials were modeled according to the vendor’s specifications. MC dose calculations were then performed using our in-house developed fast MC dose engine for HDR brachytherapy (gBMC) on a GPU platform, which is able to simulate both photon transport and electron transport in a voxelized geometry. A phase-space file for the Ir-192 HDR source was used as a source model for MC simulations. Results: Satisfactory agreements between the dose distributions calculated by Acuros BV and those calculated by gBMC were observed in all cases. Quantitatively, we computed point-wise dose difference within the region that receives a dose higher than 10% of the reference dose, defined to be the dose at 5mm outward away from the applicator surface. The mean dose difference was ∼0.45%–0.51% and the 95-percentile maximum difference was ∼1.24%–1.47%. Conclusion: Acuros BV is able to accurately perform dose calculations in HDR brachytherapy with a shielded cylinder applicator.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

TU-F-201-02: Applications in SRS, SBRT, IMRT, VMAT, and KV Imaging

Since the introduction of radiochromic films (RCF) for radiation dosimetry, the scope of RCF dosimetry has expanded steadily to include many medical applications, such as radiation therapy and diagnostic radiology. The AAPM Task Group (TG) 55 published a report on the recommendations for RCF dosimetry in 1998. As the technology is advancing rapidly, and its routine clinical use is expanding, TG 235 has been formed to provide an update to TG-55 on radiochromic film dosimetry. RCF dosimetry applications in clinical radiotherapy have become even more widespread, expanding from primarily brachytherapy and radiosurgery applications, and gravitating towards (but not limited to) external beam therapy (photon, electron and protons), such as quality assurance for IMRT, VMAT, Tomotherapy, SRS/SRT, and SBRT. In addition, RCF applications now extend to measurements of radiation dose in particle beams and patients undergoing medical exams, especially fluoroscopically guided interventional procedures and CT. The densitometers/scanners used for RCF dosimetry have also evolved from the He-Ne laser scanner to CCD-based scanners, including roller-based scanner, light box-based digital camera, and flatbed color scanner. More recently, multichannel RCF dosimetry introduced a new paradigm for external beam dose QA for its high accuracy and efficiency. This course covers in detail the recent advancements in RCF dosimetry. Learning Objectives: Introduce the paradigm shift on multichannel film dosimetry Outline the procedures to achieve accurate dosimetry with a RCF dosimetry system Provide comprehensive guidelines on RCF dosimetry for various clinical applications One of the speakers has a research agreement from Ashland Inc., the manufacturer of Gafchromic film.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

TU-F-201-03: Applications in Brachytherapy

60 APPLIED LIFE SCIENCES↗