Materials
The Impact of Extraneous Variables on the Performance of Recurrent Neural Network Models in Clinical Tasks
Laksana, Eugene, Aczon, Melissa, Ho, Long, Carlin, Cameron, Ledbetter, David, Wetzel, Randall
Electronic Medical Records (EMR) are a rich source of patient information, including measurements reflecting physiologic signs and administered therapies. Identifying which variables are useful in predicting clinical outcomes can be challenging. Advanced algorithms such as deep neural networks were designed to process high-dimensional inputs containing variables in their measured form, thus bypass separate feature selection or engineering steps. We investigated the effect of extraneous input variables on the predictive performance of Recurrent Neural Networks (RNN) by including in the input vector extraneous variables randomly drawn from theoretical and empirical distributions. RNN models using different input vectors (EMR variables; EMR and extraneous variables; extraneous variables only) were trained to predict three clinical outcomes: in-ICU mortality, 72-hour ICU re-admission, and 30-day ICU-free days. The measured degradations of the RNN's predictive performance with the addition of extraneous variables to EMR variables were negligible.
Transfer Learning Using Ensemble Neural Networks for Organic Solar Cell Screening
Paul, Arindam, Jha, Dipendra, Al-Bahrani, Reda, Liao, Wei-keng, Choudhary, Alok, Agrawal, Ankit
Organic Solar Cells are a promising technology for solving the clean energy crisis in the world. However, generating candidate chemical compounds for solar cells is a time-consuming process requiring thousands of hours of laboratory analysis. For a solar cell, the most important property is the power conversion efficiency which is dependent on the highest occupied molecular orbitals (HOMO) values of the donor molecules. Recently, machine learning techniques have proved to be very useful in building predictive models for HOMO values of donor structures of Organic Photovoltaic Cells (OPVs). Since experimental datasets are limited in size, current machine learning models are trained on data derived from calculations based on density functional theory (DFT). Molecular line notations such as SMILES or InChI are popular input representations for describing the molecular structure of donor molecules. The two types of line representations encode different information, such as SMILES defines the bond types while InChi defines protonation. In this work, we present an ensemble deep neural network architecture, called SINet, which harnesses both the SMILES and InChI molecular representations to predict HOMO values and leverage the potential of transfer learning from a sizeable DFT-computed dataset- Harvard CEP to build more robust predictive models for relatively smaller HOPV datasets. Harvard CEP dataset contains molecular structures and properties for 2.3 million candidate donor structures for OPV while HOPV contains DFT-computed and experimental values of 350 and 243 molecules respectively. Our results demonstrate significant performance improvement from the use of transfer learning and leveraging both molecular representations.
Measuring the Similarity between Materials with an Emphasis on the Materials Distinctiveness
Dang, Tran-Thai, Pham, Tien-Lam, Kino, Hiori, Miyake, Takashi, Dam, Hieu-Chi
In this study, we establish a basis for selecting similarity measures when applying machine learning techniques to solve materials science problems. This selection is considered with an emphasis on the distinctiveness between materials that reflect their nature well. We perform a case study with a dataset of rare-earth transition metal crystalline compounds represented using the Orbital Field Matrix descriptor and the Coulomb Matrix descriptor. We perform predictions of the formation energies using k-nearest neighbors regression, ridge regression, and kernel ridge regression. Through detailed analyses of the yield prediction accuracy, we examine the relationship between the characteristics of the material representation and similarity measures, and the complexity of the energy function they can capture. Empirical experiments and theoretical analysis reveal that similarity measures and kernels that minimize the loss of materials distinctiveness improve the prediction performance.
Harmless interpolation of noisy data in regression
Muthukumar, Vidya, Vodrahalli, Kailas, Sahai, Anant
In classification problems (i.e. when the labels Y are discrete), the scaling of the test error with respect to n is determined by characterizations of the VC-dimension [2]/Rademacher complexity [3] of the function class, which in the worst case increases with its number of parameters. In regression (i.e. when the labels Y are continuous), the mean-squared error of the ordinary least-squares estimate is characterized by the condition number of the regression matrix, which is reasonable for appropriate ratios of d/n but tends to increase astronomically as d approaches n. The qualitative fear is the same: if the function class is too complex, it starts to overfit noise and can generalize poorly to unseen test data. But there is a gap between "can" and "will" -- and indeed this conventional wisdom has been challenged by the recent advent of deeper and deeper neural networks. In particular, a thought-provoking paper [4] noted that several deep neural networks generalize well despite achieving zero or close to zero training error, and being so expressive that they even have the ability to fit pure noise. As they put it, "understanding deep learning requires rethinking generalization". How can we reconcile the fact that good interpolative solutions exist with the classical bias-variance tradeoff? These phenomena are being actively investigated in a statistical sense [5,6] and a computational sense [7-9] in classification problems and/or noiseless models.
Scientists develop Terminator-style stretchable liquid metal
A new host of liquid metals that have applications towards soft robotics are making movies like'The Terminator' transcend make-believe. According to researchers, experimental liquid metals like gallium and other alloys, when supplemented with nickel or iron, are able to flex and mold into shapes with the use of magnets, much like the iconic movie villain, T-1000 from'The Terminator 2: Judgement Day.' While other such metals have been developed, they contended with two major drawbacks. A new host of liquid metals that have applications towards soft robotics are making movies like'The Terminator' transcend make-believe toward real life. Researchers say experimental liquid metals like gallium and other alloys, when supplemented with nickel or iron, are able to flex and mold into shapes with the use of magnets. A new material revealed by the American Chemical Society solves to major problems experienced by similar substances.
The Amazing Ways John Deere Uses AI And Machine Vision To Help Feed 10 Billion People
In just 30 years' time, it is forecasted that the human population of our planet will be close to 10 billion. Producing enough food to feed these hungry mouths will be a challenge, and demographic trends such as urbanization, particularly in developing countries, will only add to that. To meet that challenge, agricultural businesses are pinning their hopes on technology, and that idea that increasingly sophisticated data and analytics tools will help to drive efficiencies and cut waste in agriculture and food production. Leading the way is John Deere – the 180-year-old manufacturer of farming and industrial machinery which has spent the past decade transforming itself into an artificial intelligence (AI) and data-driven business. I have covered John Deere before here.
Data Mining vs. Machine Learning: What's The Difference? Import.io
Machine learning embodies the principles of data mining, but can also make automatic correlations and learn from them to apply to new algorithms. It's the technology behind self-driving cars that can quickly adjust to new conditions while driving. Machine learning also provides instant recommendations when a buyer purchases a product from Amazon. These algorithms and analytics are constantly meant to be improving, so the result will only get more accurate over time. Machine learning isn't artificial intelligence, but the ability to learn and improve is still an impressive feat.
This Robot Built a House in 3 Days
HADRIAN X, a robot developed by Australian company FBR (formerly known as Fastbrick Robotics), has successfully completed its first full-scale test by building a 180 square metre house with three bedrooms and two bathrooms. Initially, Hadrian X was made to pass Factory Acceptance Testing (FAT), which focused on its ability to work with bricks of different sizes and cuts, building from a CAD model and building tall or "from slab to cap". Above: Hadrian X laying blocks to complete Factory Acceptance Testing (image courtesy of FBR). After completing the trial, Hadrian X completed its first full home structure in less than three days. The structure was verified by independent civil and structural engineers as having met the relevant building standards.
Deveron Receives AI for Earth Grant from Microsoft
Toronto, Ontario--(Newsfile Corp. - March 11, 2019) - Deveron UAS Corp. ("Deveron" or the "Company") and Deveron's wholly owned data analytics subsidiary, Veritas Farm Management ()Veritas") have been awarded an AI for Earth grant from Microsoft to help further our efforts in artificial intelligence ()AI") and making recommendations and predictions using agricultural data. This new grant will provide Deveron with Microsoft Azure computing resources and AI tools to accelerate our work on utilizing in-season imagery and AI to apply nitrogen fertilizer to corn. Deveron will help growers more fully utilize the nitrogen credit produced when cover crops are introduced into crop rotation. Additional nitrogen can then be applied as needed using variable rate applications around these credits, insuring that the nitrogen needs of the crop is met in an efficient way across the field. "We are excited to be chosen by Microsoft to participate in this transformational opportunity" reported David Macmillan, President and CEO of Deveron.
Deep learning for molecular generation and optimization - a review of the state of the art
Elton, Daniel C., Boukouvalas, Zois, Fuge, Mark D., Chung, Peter W.
In the space of only a few years, deep generative modeling has revolutionized how we think of artificial creativity, yielding autonomous systems which produce original images, music, and text. Inspired by these successes, researchers are now applying deep generative modeling techniques to the generation and optimization of molecules - in our review we found 45 papers on the subject published in the past two years. These works point to a future where such systems will be used to generate lead molecules, greatly reducing resources spent downstream synthesizing and characterizing bad leads in the lab. In this review we survey the increasingly complex landscape of models and representation schemes that have been proposed. The four classes of techniques we describe are recursive neural networks, autoencoders, generative adversarial networks, and reinforcement learning. After first discussing some of the mathematical fundamentals of each technique, we draw high level connections and comparisons with other techniques and expose the pros and cons of each. Several important high level themes emerge as a result of this work, including the shift away from the SMILES string representation of molecules towards more sophisticated representations such as graph grammars and 3D representations, the importance of reward function design, the need for better standards for benchmarking and testing, and the benefits of adversarial training and reinforcement learning over maximum likelihood based training.