analog
AI-Informed Model Analogs for Subseasonal-to-Seasonal Prediction
Landsberg, Jacob B., Barnes, Elizabeth A., Newman, Matthew
Subseasonal-to-seasonal forecasting is crucial for public health, disaster preparedness, and agriculture, and yet it remains a particularly challenging timescale to predict. We explore the use of an interpretable AI-informed model analog forecasting approach, previously employed on longer timescales, to improve S2S predictions. Using an artificial neural network, we learn a mask of weights to optimize analog selection and showcase its versatility across three varied prediction tasks: 1) classification of Week 3-4 Southern California summer temperatures; 2) regional regression of Month 1 midwestern U.S. summer temperatures; and 3) classification of Month 1-2 North Atlantic wintertime upper atmospheric winds. The AI-informed analogs outperform traditional analog forecasting approaches, as well as climatology and persistence baselines, for deterministic and probabilistic skill metrics on both climate model and reanalysis data. We find the analog ensembles built using the AI-informed approach also produce better predictions of temperature extremes and improve representation of forecast uncertainty. Finally, by using an interpretable-AI framework, we analyze the learned masks of weights to better understand S2S sources of predictability.
- North America > United States > California (0.55)
- Pacific Ocean (0.04)
- Oceania > New Zealand (0.04)
- (5 more...)
- Health & Medicine (0.66)
- Food & Agriculture > Agriculture (0.34)
SynTwins: A Retrosynthesis-Guided Framework for Synthesizable Molecular Analog Generation
Chen, Shuan, Nam, Gunwook, Aspuru-Guzik, Alan, Jung, Yousung
The disconnect between AI-generated molecules with desirable properties and their synthetic feasibility remains a critical bottleneck in computational discovery of drugs and materials. While generative AI has accelerated the proposal of candidate molecules, many of these structures prove challenging or impossible to synthesize using established chemical reactions. Here, we introduce SynTwins, a novel retrosynthesis-guided molecule design framework that finds synthetically accessible molecular analogs by emulating expert chemists' strategies in three steps: retrosynthesis, searching similar building blocks, and virtual synthesis. Using a search algorithm instead of a stochastic data-driven generator, SynTwins outperforms state-of-the-art machine learning models at exploring synthetically accessible analogs while maintaining high structural similarity to original target molecules. Furthermore, when integrated into existing molecular property-optimization frameworks, our hybrid approach produces synthetically feasible analogs with minimal loss in property scores. Our comprehensive benchmarking across diverse molecular datasets demonstrates that SynTwins effectively bridges the gap between computational design and experimental synthesis, providing a practical solution for accelerating the discovery of synthesizable molecules with desired properties for a wide range of applications.
- North America > United States (0.74)
- North America > Canada > Ontario > Toronto (0.14)
- Asia > South Korea > Seoul > Seoul (0.05)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Optimization (0.66)
- Information Technology > Artificial Intelligence > Natural Language > Generation (0.48)
- Information Technology > Artificial Intelligence > Machine Learning > Neural Networks > Deep Learning > Generative AI (0.34)
GRU-ODE and GRU-Bayes have complementary
We thank reviewers for the relevant comments. We first address general questions and then give brief individual answers. Those projected distributions vary smoothly as they are driven by an ODE. Continuous-time Bayesian networks (Nodelman et al., UAI 2002) address a This joint modeling of continuous measurements and events was left for future work. Some assumptions have to be made about the conditional distribution of the observations.
- Asia > Singapore (0.04)
- Asia > Indonesia > Bali (0.04)
- North America > United States > Louisiana > Orleans Parish > New Orleans (0.04)
- (4 more...)
- Research Report > New Finding (1.00)
- Research Report > Experimental Study (1.00)
- Information Technology > Artificial Intelligence > Representation & Reasoning (0.94)
- Information Technology > Artificial Intelligence > Natural Language > Large Language Model (0.48)
- Information Technology > Artificial Intelligence > Cognitive Science > Problem Solving (0.47)
- Information Technology > Artificial Intelligence > Machine Learning > Neural Networks (0.47)
GRU-ODE and GRU-Bayes have complementary
We thank reviewers for the relevant comments. We first address general questions and then give brief individual answers. Those projected distributions vary smoothly as they are driven by an ODE. Continuous-time Bayesian networks (Nodelman et al., UAI 2002) address a This joint modeling of continuous measurements and events was left for future work. Some assumptions have to be made about the conditional distribution of the observations.
- Asia > China (0.28)
- North America > United States (0.14)
- Africa > Rwanda (0.14)
- Research Report > New Finding (1.00)
- Research Report > Experimental Study (1.00)
- Information Technology > Artificial Intelligence > Representation & Reasoning (0.94)
- Information Technology > Artificial Intelligence > Natural Language > Large Language Model (0.47)
- Information Technology > Artificial Intelligence > Cognitive Science > Problem Solving (0.47)
- Information Technology > Artificial Intelligence > Machine Learning > Neural Networks (0.46)
Machine Intelligence on Wireless Edge Networks
Vadlamani, Sri Krishna, Sulimany, Kfir, Gao, Zhihui, Chen, Tingjun, Englund, Dirk
Machine intelligence on edge devices enables low-latency processing and improved privacy, but is often limited by the energy and delay of moving and converting data. Current systems frequently avoid local model storage by sending queries to a server, incurring uplink cost, network latency, and privacy risk. We present the opposite approach: broadcasting model weights to clients that perform inference locally using in-physics computation inside the radio receive chain. A base station transmits weights as radio frequency (RF) waveforms; the client encodes activations onto the waveform and computes the result using existing mixer and filter stages, RF components already present in billions of edge devices such as cellphones, eliminating repeated signal conversions and extra hardware. Analysis shows that thermal noise and nonlinearity create an optimal energy window for accurate analog inner products. Hardware-tailored training through a differentiable RF chain preserves accuracy within this regime. Circuit-informed simulations, consistent with a companion experiment, demonstrate reduced memory and conversion overhead while maintaining high accuracy in realistic wireless edge scenarios.
- North America > United States > North Carolina > Durham County > Durham (0.04)
- North America > United States > Massachusetts > Middlesex County > Cambridge (0.04)
- Europe > Slovenia > Drava > Municipality of Benedikt > Benedikt (0.04)
- Education (0.46)
- Leisure & Entertainment (0.34)
Learning-Based Multiuser Scheduling in MIMO-OFDM Systems with Hybrid Beamforming
Agheli, Pouya, Kobal, Tugce, Durand, François, Andrews, Matthew
We investigate the multiuser scheduling problem in multiple-input multiple-output (MIMO) systems using orthogonal frequency division multiplexing (OFDM) and hybrid beamforming in which a base station (BS) communicates with multiple users over millimeter wave (mmWave) channels in the downlink. Improved scheduling is critical for enhancing spectral efficiency and the long-term performance of the system from the perspective of proportional fairness (PF) metric in hybrid beamforming systems due to its limited multiplexing gain. Our objective is to maximize PF by properly designing the analog and digital precoders within the hybrid beamforming and selecting the users subject to the number of radio frequency (RF) chains. Leveraging the characteristics of mmWave channels, we apply a two-timescale protocol. On a long timescale, we assign an analog beam to each user. Scheduling the users and designing the digital precoder are done accordingly on a short timescale. To conduct scheduling, we propose combinatorial solutions, such as greedy and sorting algorithms, followed by a machine learning (ML) approach. Our numerical results highlight the trade-off between the performance and complexity of the proposed approaches. Consequently, we show that the choice of approach depends on the specific criteria within a given scenario.
- North America > Cuba (0.04)
- Europe > France (0.04)
Signatures of planets and Galactic subpopulations in solar analogs. Precise chemical abundances with neural networks
Martos, Giulia, Meléndez, Jorge, Spina, Lorenzo, Lucatello, Sara
The aim of this work is to obtain precise atmospheric parameters and chemical abundances automatically for solar twins and analogs to find signatures of exoplanets, as well as to assess how peculiar the Sun is compared to these stars and to analyze any possible fine structures in the Galactic thin disk. We developed a neural network (NN) algorithm using Python to obtain these parameters for a sample of 99 solar twins and solar analogs previously studied in the literature from normalized high-quality spectra from HARPS, with a resolving power of R $\sim$ 115000 and a signal-to-noise ratio S/N > 400. We obtained precise atmospheric parameters and abundance ratios [X/Fe] of 20 chemical elements (Li, C, O, Na, Mg, Al, Si, S, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, and Ba). The results are in line with the literature, with average differences and standard deviations of $(2 \pm 27)$ K for T$_{\rm eff}$, $(0.00 \pm 0.06)$ dex for log g, $(0.00 \pm 0.02)$ dex for [Fe/H], $(-0.01 \pm 0.05)$ km s$^{-1}$ for microturbulence velocity, $(0.02 \pm 0.08)$ km s$^{-1}$ for the macro turbulence velocity, and $(-0.12 \pm 0.26)$ km s$^{-1}$ for the projected rotational velocity (vsin$i$). Regarding the chemical abundances, most of the elements agree with the literature within 0.01 - 0.02 dex. The abundances were corrected from the effects of the Galactic chemical evolution and analyzed with the condensation temperature (T$_{\rm cond}$) to verify whether the stars presented depletion of refractories compared to volatiles. We found that the Sun is more depleted in refractory elements compared to volatiles than 89% of the studied solar analogs, with a significance of 9.5$σ$ when compared to the stars without detected exoplanets. We also found the possible presence of three subpopulations in the solar analogs: one Cu-rich, one Cu-poor, and the last one slightly older and poor in Na.
- South America > Brazil > São Paulo (0.04)
- North America > United States (0.04)
- Europe > Italy (0.04)
- (2 more...)
SynLlama: Generating Synthesizable Molecules and Their Analogs with Large Language Models
Sun, Kunyang, Bagni, Dorian, Cavanagh, Joseph M., Wang, Yingze, Sawyer, Jacob M., Gritsevskiy, Andrew, Head-Gordon, Teresa
Generative machine learning models for small molecule drug discovery have shown immense promise, but many molecules generated by this approach are too difficult to synthesize to be worth further investigation or further development. We present a novel approach by fine-tuning Meta's Llama3 large language models (LLMs) to create SynLlama, which generates full synthetic pathways made of commonly accessible Enamine building blocks and robust organic reaction templates. SynLlama explores a large synthesizable space using significantly less data compared to other state-of-the-art methods, and offers strong performance in bottom-up synthesis, synthesizable analog generation, and hit expansion, offering medicinal chemists a valuable tool for drug discovery developments. We find that SynLlama can effectively generalize to unseen yet purchasable building blocks, meaning that its reconstruction capabilities extend to a broader synthesizable chemical space than the training data.
- North America > United States > California > San Francisco County > San Francisco (0.14)
- North America > United States > Minnesota > Hennepin County > Minneapolis (0.14)
- North America > United States > California > Alameda County > Berkeley (0.14)
- Africa > Rwanda > Kigali > Kigali (0.04)