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At least 1,387 records · Page 77

Learning Heterogeneous Features Jointly: A Deep End-to-End Framework for Multi-Step Short-Term Wind Power Prediction

Leveraging multiple heterogeneous measurements to predict wind power has long been a challenging task in the electrical community. In this paper, a deep architecture incorporated with multitask learning and multimodal learning for wind power prediction, termed predictive stacked autoencoder (PSAE), is presented. PSAE is a unified framework integrating multiple stacked autoencoders (SAEs), one feature fusion layer, and one prediction terminal layer, which expands the architecture from two spatial dimensions, including the depth and width, compared to conventional prediction models. Initially, the SAEs at the bottom of PSAE extracted features from multiple kinds of measurements respectively. Following, the feature fusion layer encodes the high-order features extracted by different SAEs into a unified feature that is more informative and representative for wind power prediction. Finally, the prediction terminal layer functions as a regression machine which generates the predicted targets based on the fusion features. Trained in an end-to-end (E2E) manner, PSAE is capable of learning heterogeneous features jointly and achieving the prediction task of sequence-to-sequence (S2S). Experiments for multi-step short-term predictions are conducted on real-world data, and the results demonstrate the superiority of PSAE to prior methods.

17 WIND ENERGY↗

TbsP and TrmB jointly regulate gapII to influence cell development phenotypes in the archaeon Haloferax volcanii

Abstract Microbial cells must continually adapt their physiology in the face of changing environmental conditions. Archaea living in extreme conditions, such as saturated salinity, represent important examples of such resilience. The model salt‐loving organism Haloferax volcanii exhibits remarkable plasticity in its morphology, biofilm formation, and motility in response to variations in nutrients and cell density. However, the mechanisms regulating these lifestyle transitions remain unclear. In prior research, we showed that the transcriptional regulator, TrmB, maintains the rod shape in the related species Halobacterium salinarum by activating the expression of enzyme‐coding genes in the gluconeogenesis metabolic pathway. In Hbt. salinarum , TrmB‐dependent production of glucose moieties is required for cell surface glycoprotein biogenesis. Here, we use a combination of genetics and quantitative phenotyping assays to demonstrate that TrmB is essential for growth under gluconeogenic conditions in Hfx. volcanii . The ∆ trmB strain rapidly accumulated suppressor mutations in a gene encoding a novel transcriptional regulator, which we name t rm B s u p pressor, or TbsP (a.k.a. “tablespoon”). TbsP is required for adhesion to abiotic surfaces (i.e., biofilm formation) and maintains wild‐type cell morphology and motility. We use functional genomics and promoter fusion assays to characterize the regulons controlled by each of TrmB and TbsP, including joint regulation of the glucose‐dependent transcription of gapII , which encodes an important gluconeogenic enzyme. We conclude that TrmB and TbsP coregulate gluconeogenesis, with downstream impacts on lifestyle transitions in response to nutrients in Hfx. volcanii .

Biochemistry & Molecular Biology↗

Call Center Arrivals: When to Jointly Forecast Multiple Streams?

We consider call centers that have multiple (potentially inter‐dependent) demand arrival streams. Workforce management of such labor intensive service systems starts with forecasting future arrival demand. We investigate the question of whether and when to jointly forecast future arrivals of the multiple streams. We first develop a general statistical model to simultaneously forecast multi‐stream arrival rates. The model takes into account three types of inter‐stream dependence. We then show with analytical and simulation studies how the forecasting benefits of the multi‐stream forecasting model vary by the type, direction, and strength of inter‐stream dependence. In particular, we find that it is beneficial to simultaneously forecast multi‐stream arrivals (instead of separately forecasting each stream), when there exists inter‐stream lag dependence among daily arrival rates. Empirical studies, using two real call center datasets further demonstrate our findings, and provide operational insights into how one chooses forecasting models for multi‐stream arrivals.

Ye, Han↗

ASSESSING THE EFFECTIVENESS OF ULTRASONIC IMPACT TREATMENT ON RESIDUAL STRESS PROFILES IN DISSIMILAR WELDED JOINTS

Residual stresses (RS) induced during welding processes are a critical concern in materials engineering, as they can significantly impair the mechanical performance of components by reducing fatigue strength and tensile load capacity. This challenge is especially pronounced in dissimilar metal welds (DMWs), where variations in thermal expansion properties between the joined alloys exacerbate the formation of tensile RS. Conventional post-weld heat treatments, though effective for homogeneous materials, often require substantial energy, specialized equipment, and extensive processing time, making them less practical for DMW applications. Thus, there is a clear need for innovative, energy-efficient techniques to mitigate these detrimental stresses. This study investigates ultrasonic impact treatment (UIT) as a possible alternative for mitigating tensile RS in both similar and dissimilar metal welds. To evaluate UIT’s effectiveness, neutron diffraction (ND) was employed as a nondestructive technique to quantify RS in three orthogonal directions—longitudinal, transverse, and normal. The results showed that UIT significantly reduced peak tensile RS, particularly in the longitudinal direction, by up to 180 MPa in similar welds and up to 150 MPa in dissimilar welds. Given the limited literature on UIT application in DMWs, this work contributes valuable data on stress redistribution mechanisms and highlights UIT’s potential as a practical stress-relief method. The findings lay the groundwork for further investigations aimed at optimizing process parameters and understanding long-term performance in welded joints.

EisaZadeh, Hamid [Western Carolina University, Cul↗

MO-C-BRE-01: The WMIS-AAPM Joint Symposium: Advances in Molecular Imaging

This joint symposium of the World Molecular Imaging Society (WMIS) and the AAPM includes three luminary speakers discussing work in new paradigms of molecular imaging in cancer (Contag), applications of optical imaging technologies to radiation therapy (Pogue) and an update on PET imaging as a surrogate biomarker for cancer progression and response to therapy. Learning Objectives: Appreciate the current trends in molecular and systems imaging. Understand how optical imaging technologies, and particularly Cerenkov detectors, can be used in advancing radiation oncology. Stay current on new PET tracers - and targets - of interest in cancer treatment.

60 APPLIED LIFE SCIENCES↗

TU-C-16A-01: Joint AAPM/SEFM/AMPR Educational Workshop On “Education of Radiotherapy Physicists”

This workshop is jointly organized by the AAPM, the Spanish (SEFM) and the Russian (AMPR) Medical Physics Societies, as part of formal educational exchange agreements signed by the AAPM with each one of these two societies.With the rapid technological advances in radiation therapy both for treatment and imaging, it is challenging how physics is taught to medical physicists practicing in radiation therapy. The main Objectives: of this workshop is to bring forth current status, challenges and issues related to education of radiation therapy physicists here in the US, Spain and Russia. Medical physicists from each one of these countries will present educational requirements of international recommendations and directives and analyze their impact on national legislations. Current and future educational models and plans for harmonization will be described. The role of universities, professional societies and examination boards, such as the American Board of Radiology, will be discussed. Minimum standards will be agreed upon. Learning Objectives: Review medical physics educational models supported by AAPM, SEFM, and AMPR. Discuss the role of governmental and non-governmental organizations in elaborating and adopting medical physics syllabi. Debate minimum educational standards for medical physics education based on country-specific resources.

61 RADIATION PROTECTION AND DOSIMETRY↗

TU-C-12A-12: Differentiating Bone Lesions and Degenerative Joint Disease in NaF PET/CT Scans Using Machine Learning

Purpose: [F-18]NaF PET can be used to image bone metastases; however, tracer uptake in degenerative joint disease (DJD) often appears similar to metastases. This study aims to develop and compare different machine learning algorithms to automatically identify regions of [F-18]NaF scans that correspond to DJD. Methods: 10 metastatic prostate cancer patients received whole body [F-18]NaF PET/CT scans prior to treatment. Image segmentation resulted in 852 ROIs, 69 of which were identified by a nuclear medicine physician as DJD. For all ROIs, various PET and CT textural features were computed. ROIs were divided into training and testing sets used to train eight different machine learning classifiers. Classifiers were evaluated based on receiver operating characteristics area under the curve (AUC), sensitivity, specificity, and positive predictive value (PPV). We also assessed the added value of including CT features in addition to PET features for training classifiers. Results: The training set consisted of 37 DJD ROIs with 475 non-DJD ROIs, and the testing set consisted of 32 DJD ROIs with 308 non-DJD ROIs. Of all classifiers, generalized linear models (GLM), decision forests (DF), and support vector machines (SVM) had the best performance. AUCs of GLM (0.929), DF (0.921), and SVM (0.889) were significantly higher than the other models (p<0.001). GLM and DF, overall, had the best sensitivity, specificity, and PPV, and gave a significantly better performance (p<0.01) than all other models. PET/CT GLM classifiers had higher AUC than just PET or just CT. GLMs built using PET/CT information had superior or comparable sensitivities, specificities and PPVs to just PET or just CT. Conclusion: Machine learning algorithms trained with PET/CT features were able to identify some cases of DJD. GLM outperformed the other classification algorithms. Using PET and CT information together was shown to be superior to using PET or CT features alone. Research supported by the Prostate Cancer Foundation.

60 APPLIED LIFE SCIENCES↗

WE-E-BRF-01: The ESTRO-AAPM Joint Symposium On Imaging for Proton Treatment Planning and Guidance

In this first inaugural joint ESTRO-AAPM session we will attempt to provide some answers to the problems encountered in the clinical application of particle therapy. Indeed the main advantage is that the physical properties of ion beams offer high ballistic accuracy for tightly conformal irradiation of the tumour volume, with excellent sparing of surrounding healthy tissue and critical organs, This also its Achilles' heel calling for an increasing role of imaging to ensure safe application of the intended dose to the targeted area during the entire course of fractionated therapy. We have three distinguished speakers addressing possible solutions. Katia Parodi (Ludwig Maximilians University, Munich, Germany) To date, Positron Emission Tomography (PET) is the only technique which has been already clinically investigated for in-vivo visualization of the beam range during or shortly after ion beam delivery. The method exploits the transient amount of β{sup 2}-activity induced in nuclear interactions between the primary beam and the irradiated tissue, depending on the ion beam species, the tissue elemental composition and physiological properties (in terms of biological clearance), as well as the time course of irradiation and imaging. This contribution will review initial results, ongoing methodological developments and remaining challenges related to the clinical usage of viable but often suboptimal instrumentation and workflows of PET-based treatment verification. Moreover, it will present and discuss promising new detector developments towards next-generation dedicated PET scanners relying on full-ring or dual-head designs for in-beam quasi real-time imaging. Denis Dauvergne (Institut de Physique Nucleaire de Lyon, Lyon, France) Prompt gamma radiation monitoring of hadron therapy presents the advantage of real time capability to measure the ion range. Both simulations and experiments show that millimetric verification of the range can be achieved at the pencil beam scale for active proton beam delivery in homogenous targets. The development of gamma cameras, that has been studied by several groups worldwide over the last years, now reaches - for some of them - the stage of being applicable in clinical conditions, with real size prototypes and count rate capability matching the therapeutic beam intensities. We will review the different concepts of gamma cameras, the advantages and limitations of this method, and the main challenges that should still be overcome before the widespread of prompt gamma quality assurance for proton and hadrontherapy. Jon Kruse (Mayo Clinic, Rochester, MN, USA) Treatment simulation images for proton therapy are used to determine proton stopping power and range in the patient. This talk will discuss the careful control of CT numbers and conversion of CT number to stopping power required in proton therapy. Imaging for treatment guidance of proton therapy also presents unique challenges which will be addressed. Among them are the enhanced relationship between internal anatomy changes and dosimetry, the need for imaging to support adaptive planning protocols, and high operational efficiency. Learning Objectives: To learn about the possibilities of using activation products to determine the range of particle beams in a patient treatment setting To be informed on an alternative methodology using prompt gamma detectors To understand the impact of the accuracy of the knowledge of the patient information with respect to the delivered treatment.

60 APPLIED LIFE SCIENCES↗

SU-F-J-97: A Joint Registration and Segmentation Approach for Large Bladder Deformations in Adaptive Radiotherapy

Purpose: To improve results of deformable image registration (DIR) in adaptive radiotherapy for large bladder deformations in CT/CBCT pelvis imaging. Methods: A variational multi-modal DIR algorithm is incorporated in a joint iterative scheme, alternating between segmentation based bladder matching and registration. Using an initial DIR to propagate the bladder contour to the CBCT, in a segmentation step the contour is improved by discrete image gradient sampling along all surface normals and adapting the delineation to match the location of each maximum (with a search range of +−5/2mm at the superior/inferior bladder side and step size of 0.5mm). An additional graph-cut based constraint limits the maximum difference between neighboring points. This improved contour is utilized in a subsequent DIR with a surface matching constraint. By calculating an euclidean distance map of the improved contour surface, the new constraint enforces the DIR to map each point of the original contour onto the improved contour. The resulting deformation is then used as a starting guess to compute a deformation update, which can again be used for the next segmentation step. The result is a dense deformation, able to capture much larger bladder deformations. The new method is evaluated on ten CT/CBCT male pelvis datasets, calculating Dice similarity coefficients (DSC) between the final propagated bladder contour and a manually delineated gold standard on the CBCT image. Results: Over all ten cases, an average DSC of 0.93±0.03 is achieved on the bladder. Compared with the initial DIR (0.88±0.05), the DSC is equal (2 cases) or improved (8 cases). Additionally, DSC accuracy of femoral bones (0.94±0.02) was not affected. Conclusion: The new approach shows that using the presented alternating segmentation/registration approach, the results of bladder DIR in the pelvis region can be greatly improved, especially for cases with large variations in bladder volume. Fraunhofer MEVIS received funding from a research grant by Varian Medical Systems.

60 APPLIED LIFE SCIENCES↗

MO-DE-206-00: Joint AAPM-WMIS Symposium: Metabolic Imaging of Cancer

In this symposium jointly sponsored by the World Molecular Imaging Society (WMIS) and the AAPM, luminary speakers on imaging metabolism will discuss three impactful topics. The first presentation on Cellular Metabolism of FDG will be given by Guillem Pratx (Stanford). This presentation will detail new work on looking at how the most common molecular imaging agent, fluoro-deoxy-glucose is metabolized at a cellular level. This will be followed by a talk on an improved approach to whole-body PET imaging by Simon Cherry (UC Davis). Simon’s work on a new whole-body PET imaging system promises to have dramatic improvement in our ability to detect and characterize cancer using PET. Finally, Jim Bankson (MD Anderson) will discuss extremely sophisticated approaches to quantifying hyperpolarized-13-C pyruvate metabolism using MR imaging. This technology promises to compliment the exquisite sensitivity of PET with an ability to measure not just uptake, but tumor metabolism. Learning Objectives: Understand the metabolism of FDG at a cellular level. Appreciate the engineering related to a novel new high-sensitivity whole-body PET imaging system. Understand the process of hyperpolarization, how pyruvate relates to metabolism and how advanced modeling can be used to better quantify this data. G. Pratx, Funding: 5R01CA186275, 1R21CA193001, and Damon Runyon Cancer Foundation. S. Cherry, National Institutes of Health; University of California, Davis; Siemens Medical SolutionsJ. Bankson, GE Healthcare; NCI P30-CA016672; CPRIT PR140021-P5.

60 APPLIED LIFE SCIENCES↗

MO-FG-BRC-00: Joint AAPM-ESTRO Symposium: Advances in Experimental Medical Physics

Experimental research in medical physics has expanded the limits of our knowledge and provided novel imaging and therapy technologies for patients around the world. However, experimental efforts are challenging due to constraints in funding, space, time and other forms of institutional support. In this joint ESTRO-AAPM symposium, four exciting experimental projects from four different countries are highlighted. Each project is focused on a different aspect of radiation therapy. From the USA, we will hear about a new linear accelerator concept for more compact and efficient therapy devices. From Canada, we will learn about novel linear accelerator target design and the implications for imaging and therapy. From France, we will discover a mature translational effort to incorporate theranostic nanoparticles in MR-guided radiation therapy. From Germany, we will find out about a novel in-treatment imaging modality for particle therapy. These examples of high impact, experimental medical physics research are representative of the diversity of such efforts that are on-going around the globe. J. Robar, Research is supported through collaboration with Varian Medical Systems and Brainlab AGD. Westerly, This work is supported by the Department of Radiation Oncology at the University of Colorado School of Medicine. COI: NONEK. Parodi, Part of the presented work is supported by the DFG (German Research Foundation) Cluster of Excellence MAP (Munich-Centre for Advanced Photonics) and has been carried out in collaboration with IBA.

60 APPLIED LIFE SCIENCES↗

The Joint Institute for Nuclear Research in Experimental Physics of Elementary Particles

The year 2016 marks the 60th anniversary of the Joint Institute for Nuclear Research (JINR) in Dubna, an international intergovernmental organization for basic research in the fields of elementary particles, atomic nuclei, and condensed matter. Highly productive advances over this long road clearly show that the international basis and diversity of research guarantees successful development (and maintenance) of fundamental science. This is especially important for experimental research. In this review, the most significant achievements are briefly described with an attempt to look into the future (seven to ten years ahead) and show the role of JINR in solution of highly important problems in elementary particle physics, which is a fundamental field of modern natural sciences. This glimpse of the future is full of justified optimism.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Neutron stars in $$f(\mathtt {R,L_m})$$ gravity with realistic equations of state: joint-constrains with GW170817, massive pulsars, and the PSR J0030+0451 mass-radius from NICER data

Abstract In this work, we investigate neutron stars (NS) in $$f(\mathtt {R,L_m})$$ f ( R , L m ) theory of gravity for the case $$f(\mathtt {R,L_m})= \mathtt {R}+ \mathtt {L_m}+ \sigma \mathtt {R}\mathtt {L_m}$$ f ( R , L m ) = R + L m + σ R L m , where $$\mathtt {R}$$ R is the Ricci scalar and $$\mathtt {L_m}$$ L m the Lagrangian matter density. In the term $$\sigma \mathtt {R}\mathtt {L_m}$$ σ R L m , $$\sigma $$ σ represents the coupling between the gravitational and particles fields. For the first time the hydrostatic equilibrium equations in the theory are solved considering realistic equations of state and NS masses and radii obtained are subject to joint constrains from massive pulsars, the gravitational wave event GW170817 and from the PSR J0030+0451 mass-radius from NASA’s Neutron Star Interior Composition Explorer ( NICER ) data. We show that in this theory of gravity, the mass-radius results can accommodate massive pulsars, while the general theory of relativity can hardly do it. The theory also can explain the observed NS within the radius region constrained by the GW170817 and PSR J0030+0451 observations for masses around $$1.4~M_{\odot }$$ 1.4 M ⊙ .

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Quantified fracture (joint) clustering in Archean basement, Wyoming: application of the normalized correlation count method

We demonstrate statistically significant self-organized clustering over a length scale range from 10 -2 to 10 1 m for north-striking opening-mode fractures (joints) in Late Archean Mount Owen Quartz Monzonite. Spatial arrangement is a critical fracture network attribute that until recently has only been assessed qualitatively. We use normalized fracture intensity plots and the normalized correlation count (NCC) method of Marrett et al. to discriminate clustered from randomly placed or evenly spaced patterns quantitatively over a wide range of length scales and to test the statistical significance of the resulting patterns. We propose a procedure for interpreting cluster patterns on NCC diagrams generated by the freely available spatial analysis software CorrCount. Results illustrate the efficacy of NCC to measure fracture clustering patterns in texturally homogeneous Archean granitic rock in a setting distant (>2 km) from folds or faults. In their current geological setting, these regional fractures are conduits for water flow and their patterns – and the NCC approach to defining clusters – may be useful guides to the spatial arrangement style and clustering magnitude of conductive fractures in other, less accessible fractured basement rocks.

02 PETROLEUM↗

PC-RPL: Joint Control of Routing Topology and Transmission Power in Real Low-Power and Lossy Networks

We present PC-RPL , a transmission power-controlled IPv6 routing protocol for low-power and lossy wireless networks that significantly improves the end-to-end packet delivery performance under heavy traffic compared to the standard RPL. We show through actual design, implementation, and experiments that a multihop wireless network can achieve better throughput and routing stability when transmission power and routing topology are “jointly and adaptively” controlled. Our experiments show that the predominant “fixed and uniform” transmission power strategy with “link quality and hop distance”–based routing topology construction (i.e., RPL) loses significant bandwidth due to hidden terminal and load imbalance problems. We design an adaptive and distributed control mechanism for transmission power and routing topology, named PC-RPL , on top of the standard RPL routing protocol for hidden terminal mitigation and load balancing. We implement PC-RPL on real embedded devices and evaluate its performance on a 49-node multihop testbed. PC-RPL reduces total end-to-end packet losses by approximately sevenfold without increasing hop distance compared to RPL with the highest transmission power, resulting in 17% improvement in aggregate bandwidth and 64% improvement for the worst-case node by successfully alleviating both hidden terminal and load imbalance problems.

Computer Science↗

Joint Genome Institute Analysis Workflow Service (JAWS) v2.7

The U.S. Department of Energy Joint Genome Institute (JGI) has developed the JGI Analysis Workflow Service (JAWS) as a distributed framework to run computational workflows across diverse high-performance computing (HPC) and cloud environments. JAWS enhances the reusability, scalability, and robustness of scientific workflows by orchestrating data movement, code execution, and results retrieval across multiple DOE facilities. At its core, JAWS integrates the Cromwell workflow engine to run workflows expressed in the Workflow Description Language (WDL), ensuring portability and interoperability. To provide consistent runtime environments, JAWS employs container technologies such as Shifter, Apptainer, and Docker. Workflow tasks are managed via HTCondor on HPC backends, while Globus ensures secure and efficient data transfer between sites. JAWS is deployed as a multi-site workflow manager across national laboratory computing facilities, with dedicated instances supporting community projects such as the National Microbiome Data Collaborative (NMDC) and KBase. This distributed, service-oriented architecture enables users to "write once, run anywhere," providing scalable, production-quality workflow execution.

Kirton, Edward↗

Joint Contour Location

The joint contour location method is an active learning technique that identifies input configurations that return pre-specified values of multiple independent computer experiments simultaneously. This code works with both Gaussian Processes and Deep Gaussian Processes

Quinlan, KevinR [Lawrence Livermore National Labor↗

Opportunities for Joint Water–Energy Management: Sensitivity of the 2010 Western U.S. Electricity Grid Operations to Climate Oscillations

The 2016 SECURE Water Act report’s natural water availability benchmark, combined with the 2010 level of water demand from an integrated assessment model, is used as input to drive a large-scale water management model. The regulated flow at hydropower plants and thermoelectric plants in the Western U.S. electricity grid (WECC) is translated into potential hydropower generation and generation capacity constraints. The impact on reliability (unserved energy, reserve margin) and cost (production cost, carbon emissions) of water constraints on 2010-level WECC power system operations is assessed using an electricity production cost model (PCM). Use of the PCM reveals the changes in generation dispatch that reflect the inter-regional interdependencies in water-constrained generation and the ability to use other generation resources to meet all electricity loads in the WECC. August grid operational benchmarks show a range of sensitivity in production cost (-8 to +11%) and carbon emissions (-7 to 11%). The reference reserve margin threshold of 15% above peak load is maintained in the scenarios analyzed, but in 5 out of 55 years unserved energy is observed when normal operations are maintained. There is 1 chance in 10 that a year will demonstrate unserved energy in August, which defines the system’s historical performance threshold to support impact, vulnerability, and adaptation analysis. For seasonal and longer term planning, i.e., multi-year drought, we demonstrate how the Water Scarcity Grid Impact Factor and climate oscillations (ENSO, PDO) can be used to plan for joint water-electricity management to maintain grid reliability.

adaptation↗