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At least 451 records · Page 25

Techniques and Issues in Agent-Based Modeling Validation

Validation of simulation models is extremely important. It ensures that the right model has been built and lends confidence to the use of that model to inform critical decisions. Agent-based models (ABM) have been widely deployed in different fields for studying the collective behavior of large numbers of interacting agents. However, researchers have only recently started to consider the issues of validation. Compared to other simulation models, ABM has many differences in model development, usage and validation. An ABM is inherently easier to build than a classical simulation, but more difficult to describe formally since they are closer to human cognition. Using multi-agent models to study complex systems has attracted criticisms because of the challenges involved in their validation [1]. In this report, we describe the challenge of ABM validation and present a novel approach we recently developed for an ABM system.

99 GENERAL AND MISCELLANEOUS↗

Supercomputer Assisted Generation of Machine Learning Agents for the Calibration of Building Energy Models

Building Energy Modeling (BEM) is an approach to model the energy usage in buildings for design and retrot pur- poses. EnergyPlus is the agship Department of Energy software that performs BEM for dierent types of buildings. The input to EnergyPlus can often extend in the order of a few thousand parameters which have to be calibrated manu- ally by an expert for realistic energy modeling. This makes it challenging and expensive thereby making building en- ergy modeling unfeasible for smaller projects. In this paper, we describe the \Autotune" research which employs machine learning algorithms to generate agents for the dierent kinds of standard reference buildings in the U.S. building stock. The parametric space and the variety of building locations and types make this a challenging computational problem necessitating the use of supercomputers. Millions of En- ergyPlus simulations are run on supercomputers which are subsequently used to train machine learning algorithms to generate agents. These agents, once created, can then run in a fraction of the time thereby allowing cost-eective cali- bration of building models.

autotune↗

Methods, microfluidic devices, and systems for detection of an active enzymatic agent

Embodiments of the present invention provide methods, microfluidic devices, and systems for the detection of an active target agent in a fluid sample. A substrate molecule is used that contains a sequence which may cleave in the presence of an active target agent. A SNAP25 sequence is described, for example, that may be cleaved in the presence of Botulinum Neurotoxin. The substrate molecule includes a reporter moiety. The substrate molecule is exposed to the sample, and resulting reaction products separated using electrophoretic separation. The elution time of the reporter moiety may be utilized to identify the presence or absence of the active target agent.

60 APPLIED LIFE SCIENCES↗

Methods and kits for predicting a response to an erythropoietic agent

Methods for predicting a response to an erythropoietic agent in a subject include providing a biological sample from the subject, and determining an amount in the sample of at least one peptide selected from the group consisting of SEQ ID NOS: 1-17. If there is a measurable difference in the amount of the at least one peptide in the sample, when compared to a control level of the same peptide, the subject is then predicted to have a good response or a poor response to the erythropoietic agent. Kits for predicting a response to an erythropoietic agent are further provided and include one or more antibodies, or fragments thereof, that specifically recognize a peptide of SEQ ID NOS: 1-17.

59 BASIC BIOLOGICAL SCIENCES↗

Method for removing strongly adsorbed surfactants and capping agents from metal to facilitate their catalytic applications

A method of synthesizing activated electrocatalyst, preferably having a morphology of a nanostructure, is disclosed. The method includes safely and efficiently removing surfactants and capping agents from the surface of the metal structures. With regard to metal nanoparticles, the method includes synthesis of nanoparticle(s) in polar or non-polar solution with surfactants or capping agents and subsequent activation by CO-adsorption-induced surfactant/capping agent desorption and electrochemical oxidation. The method produces activated macroparticle or nanoparticle electrocatalysts without damaging the surface of the electrocatalyst that includes breaking, increasing particle thickness or increasing the number of low coordination sites.

36 MATERIALS SCIENCE↗

Metal organic frameworks for the catalytic detoxification of chemical warfare nerve agents

A method of using a metal organic framework (MOF) comprising a metal ion and an at least bidendate organic ligand to catalytically detoxify chemical warfare nerve agents including exposing the metal-organic-framework (MOF) to the chemical warfare nerve agent and catalytically decomposing the nerve agent with the MOF.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

System and method for regeneration and recirculation of a reducing agent using highly exothermic reactions induced by mixed industrial slags

Embodiments relate to systems and methods for regenerating and recirculating a CO, H.sub.2 or combinations thereof utilized for metal oxide reduction in a reduction furnace. The reduction furnace receives the reducing agent, reduces the metal oxide, and generates an exhaust of the oxidized product. The oxidized product is transferred to a mixing vessel, where the oxidized product, a calcium oxide, and a vanadium oxide interact to regenerate the reducing agent from the oxidized product. The regenerated reducing agent is transferred back to the reduction furnace for continued metal oxide reductions.

36 MATERIALS SCIENCE↗

Object discrimination based on a swarm of agents

A configuration system for identifying a target configuration of agents for acquiring data is provided. In some embodiments, the configuration system generates sample configurations, each of which has a location within the space for each agent. The configuration system selects as the target configuration a sample configuration that is suitable to acquire data. The configuration system selects the target configuration by, for at least one or more sample configurations, directing that the agents assume the sample configuration and then acquire data when in the sample configuration. The configuration system then stores, for each sample configuration, an indication of suitability for acquiring data based on the sample configuration. The configuration system selects a sample configuration that is deemed to be suitable as the target configuration.

Beer, N. Reginald↗

Object discrimination based on a swarm of agents

A configuration system for identifying a target configuration of agents for acquiring data is provided. In some embodiments, the configuration system generates sample configurations, each of which has a location within the space for each agent. The configuration system selects as the target configuration a sample configuration that is suitable to acquire data. The configuration system selects the target configuration by, for at least one or more sample configurations, directing that the agents assume the sample configuration and then acquire data when in the sample configuration. The configuration system then stores, for each sample configuration, an indication of suitability for acquiring data based on the sample configuration. The configuration system selects a sample configuration that is deemed to be suitable as the target configuration.

Beer, Neil Reginald↗

Processing of perovskite films using inks with complexing agents

A method can comprise providing an ink comprising reactants, a complexing agent, and a solvent, depositing the ink onto a substrate to form a wet film, drying the wet film to form a precursor layer, and annealing the precursor layer to form a perovskite film. The reactants can comprise a first and a second cation, a first metal, and a first and a second anion, wherein the first and second cations are different from each other, and the first and second anions are different from each other. The complexing agent can comprise a heterocyclic donor material. The perovskite film can comprise a mixed-cation mixed-halide perovskite material, and less than 5% by mass of the complexing agent. The perovskite film can also be formed using a one-step process.

Bailie, Colin David↗

Method and composition for targeted delivery of therapeutic agents

Functionalized single walled or multi-walled carbon nanotubes (f-CNTs) can be delivered into mammals to targeted organs, such as the kidney and the liver. These f-CNTs may be non-covalently linked or covalently linked to therapeutic agents. In particular, the application delivers carbon nanotube-therapeutic agent conjugates to a target organ, thereby preventing or reducing damages to the organ caused by other agents or procedure.

McDevitt, Michael R.↗

Anion binding agent lithium salts for battery electrolytes

A method for synthesizing a purified lithium (Li)+ anion binding agent (ABA-F)− salt and the corresponding Li+(ABA-F)− are disclosed. The method includes dissolving a boron-based acid in a polar solvent to form a solution. The solution is refluxed to form an anion binding agent. A stoichiometric amount of a small fluorinated salt, such as LiF, is added to the anion binding agent to form a mixture. The mixture is subsequently crystallized to obtain a substantially pure Li+(ABA-F)− salt. Example purified Li+(ABA-F)− salts include Ox-Li+(ABA-F), m-Li+(ABA-F), and BF3—Li+(ABA-F)−. These purified Li+(ABA-F)− salts provide the benefits of increased battery thermal safety without loss of electrochemical performance.

Orendorff, Christopher↗

LC-Opt: Benchmarking Reinforcement Learning and Agentic AI for End-to-End Liquid Cooling Optimization in Data Centers

Liquid cooling is critical for thermal management in high-density data centers with the rising AI workloads. However, machine learning-based controllers are essential to unlock greater energy efficiency and reliability, promoting sustainability. We present LC-Opt, a Sustainable Liquid Cooling (LC) benchmark environment, for reinforcement learning (RL) control strategies in energy-efficient liquid cooling of high-performance computing (HPC) systems. Built on the baseline of a high-fidelity digital twin of Oak Ridge National Lab's Frontier Supercomputer cooling system, LC-Opt provides detailed Modelica-based end-to-end models spanning site-level cooling towers to data center cabinets and server blade groups. RL agents optimize critical thermal controls like liquid supply temperature, flow rate, and granular valve actuation at the IT cabinet level, as well as cooling tower (CT) setpoints through a Gymnasium interface, with dynamic changes in workloads. This environment creates a multi-objective real-time optimization challenge balancing local thermal regulation and global energy efficiency, and also supports additional components like a heat recovery unit (HRU). We benchmark centralized and decentralized multi-agent RL approaches, demonstrate policy distillation into decision and regression trees for interpretable control, and explore LLM-based methods that explain control actions in natural language through an agentic mesh architecture designed to foster user trust and simplify system management. LC-Opt democratizes access to detailed, customizable liquid cooling models, enabling the ML community, operators, and vendors to develop sustainable data center liquid cooling control solutions.

Naug, Avisek [Hewlett Packard Enterprise]↗

Automated Membership Inference Attacks: Discovering MIA Signal Computations using LLM Agents

Membership inference attacks (MIAs), which enable adversaries to determine whether specific data points were part of a model's training dataset, have emerged as an important framework to understand, assess, and quantify the potential information leakage associated with machine learning systems. Designing effective MIAs is a challenging task that usually requires extensive manual exploration of model behaviors to identify potential vulnerabilities. In this paper, we introduce AutoMIA -- a novel framework that leverages large language model (LLM) agents to automate the design and implementation of new MIA signal computations. By utilizing LLM agents, we can systematically explore a vast space of potential attack strategies, enabling the discovery of novel strategies. Our experiments demonstrate AutoMIA can successfully discover new MIAs that are specifically tailored to user-configured target model and dataset, resulting in improvements of up to 0.18 in absolute AUC over existing MIAs. This work provides the first demonstration that LLM agents can serve as an effective and scalable paradigm for designing and implementing MIAs with SOTA performance, opening up new avenues for future exploration.

Tran, Toan Viet [Emory University]↗

Analysis of Organophosphorus-Based Nerve Agent Degradation Products by Gas Chromatography-Mass Spectrometry (GC-MS): Current Derivatization Reactions in the Analytical Chemist’s Toolbox

The field of gas chromatography-mass spectrometry (GC-MS) in the analysis of chemical warfare agents (CWAs), specifically those involving the organophosphorus-based nerve agents (OPNAs), is a continually evolving and dynamic area of research. The ever-present interest in this field within analytical chemistry is driven by the constant threat posed by these lethal CWAs, highlighted by their use during the Tokyo subway attack in 1995, their deliberate use on civilians in Syria in 2013, and their use in the poisoning of Sergei and Yulia Skripal in Great Britain in 2018 and Alexei Navalny in 2020. These events coupled with their potential for mass destruction only serve to stress the importance of developing methods for their rapid and unambiguous detection. Although the direct detection of OPNAs is possible by GC-MS, in most instances, the analytical chemist must rely on the detection of the products arising from their degradation. To this end, derivatization reactions mainly in the form of silylations and alkylations employing a vast array of reagents have played a pivotal role in the efficient detection of these products that can be used retrospectively to identify the original OPNA.

sarin↗

Bayesian Calibration of Stochastic Agent Based Model via Random Forest

Agent-based models (ABM) provide an excellent framework for modeling outbreaks and interventions in epidemiology by explicitly accounting for diverse individual interactions and environments. However, these models are usually stochastic and highly parametrized, requiring precise calibration for predictive performance. When considering realistic numbers of agents and properly accounting for stochasticity, this high-dimensional calibration can be computationally prohibitive. This paper presents a random forest-based surrogate modeling technique to accelerate the evaluation of ABMs and demonstrates its use to calibrate an epidemiological ABM named CityCOVID via Markov chain Monte Carlo (MCMC). The technique is first outlined in the context of CityCOVID's quantities of interest, namely hospitalizations and deaths, by exploring dimensionality reduction via temporal decomposition with principal component analysis (PCA) and via sensitivity analysis. The calibration problem is then presented, and samples are generated to best match COVID-19 hospitalization and death numbers in Chicago from March to June in 2020. Further, these results are compared with previous approximate Bayesian calibration (IMABC) results, and their predictive performance is analyzed, showing improved performance with a reduction in computation.

60 APPLIED LIFE SCIENCES↗

Improving the recovery of Ba from Sr Resin columns using chelating agents

Age dating of Cs-137 sources necessitates the accurate and precise quantification of the isotope Ba-137. In previous efforts to determine the age of Cs-137 source material, variation in Ba recovery was the largest source of uncertainty. This work investigates the use of several common chelating agents (EDTA, CDTA, DTPA, and NTA) to strip barium from Sr Resin columns quantitatively in an effort to improve the reproducibility of the separation. Batch studies showed conditions in which CDTA, EDTA, and NTA may suppress the retention of Ba on the column. Follow-up column studies showed excellent removal of barium from the column with quantitative recovery in the appropriate elution fraction. Our report builds upon previous studies and establishes additional chelating agents that could be used in an age dating separation procedure

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗