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Deep Learning for Detecting Building Defects Using Convolutional Neural Networks

arXiv.org Artificial Intelligence

Clients are increasingly looking for fast and effective means to quickly and frequently survey and communicate the condition of their buildings so that essential repairs and maintenance work can be done in a proactive and timely manner before it becomes too dangerous and expensive. Traditional methods for this type of work commonly comprise of engaging building surveyors to undertake a condition assessment which involves a lengthy site inspection to produce a systematic recording of the physical condition of the building elements, including cost estimates of immediate and projected long-term costs of renewal, repair and maintenance of the building. Current asset condition assessment procedures are extensively time consuming, laborious, and expensive and pose health and safety threats to surveyors, particularly at height and roof levels which are difficult to access. This paper aims at evaluating the application of convolutional neural networks (CNN) towards an automated detection and localisation of key building defects, e.g., mould, deterioration, and stain, from images. The proposed model is based on pre-trained CNN classifier of VGG-16 (later compaired with ResNet-50, and Inception models), with class activation mapping (CAM) for object localisation. The challenges and limitations of the model in real-life applications have been identified. The proposed model has proven to be robust and able to accurately detect and localise building defects. The approach is being developed with the potential to scale-up and further advance to support automated detection of defects and deterioration of buildings in real-time using mobile devices and drones.


Sparse hierarchical representation learning on molecular graphs

arXiv.org Machine Learning

Architectures for sparse hierarchical representation learning have recently been proposed for graph-structured data, but so far assume the absence of edge features in the graph. We close this gap and propose a method to pool graphs with edge features, inspired by the hierarchical nature of chemistry. In particular, we introduce two types of pooling layers compatible with an edge-feature graph-convolutional architecture and investigate their performance for molecules relevant to drug discovery on a set of two classification and two regression benchmark datasets of MoleculeNet. We find that our models significantly outperform previous benchmarks on three of the datasets and reach state-of-the-art results on the fourth benchmark, with pooling improving performance for three out of four tasks, keeping performance stable on the fourth task, and generally speeding up the training process.


Why AI is an opportunity rather than a danger

#artificialintelligence

Opinion: it's likely that artificial intelligence will do more good than harm for human civilisation The solar system is full of debris and rocks floating around. A meteor shower or a shooting star is debris burning up upon entry to the atmosphere. A much larger rock that could make its way through is an asteroid. About 66 million years ago, the impact from an asteroid brought about the Cretaceous extinction. A repetition of this event is theoretically possible - and the same could be said about all-powerful Artificial Intelligence Overlords marginalising the human race. Since its inception in the mid 20th century, the field of artificial intelligence has had an interesting ride.


ASNets: Deep Learning for Generalised Planning

arXiv.org Artificial Intelligence

In this paper, we discuss the learning of generalised policies for probabilistic and classical planning problems using Action Schema Networks (ASNets). The ASNet is a neural network architecture that exploits the relational structure of (P)PDDL planning problems to learn a common set of weights that can be applied to any problem in a domain. By mimicking the actions chosen by a traditional, non-learning planner on a handful of small problems in a domain, ASNets are able to learn a generalised reactive policy that can quickly solve much larger instances from the domain. This work extends the ASNet architecture to make it more expressive, while still remaining invariant to a range of symmetries that exist in PPDDL problems. We also present a thorough experimental evaluation of ASNets, including a comparison with heuristic search planners on seven probabilistic and deterministic domains, an extended evaluation on over 18,000 Blocksworld instances, and an ablation study. Finally, we show that sparsity-inducing regularisation can produce ASNets that are compact enough for humans to understand, yielding insights into how the structure of ASNets allows them to generalise across a domain.


ChemBO: Bayesian Optimization of Small Organic Molecules with Synthesizable Recommendations

arXiv.org Machine Learning

We describe ChemBO, a Bayesian Optimization framework for generating and optimizing organic molecules for desired molecular properties. This framework is useful in applications such as drug discovery, where an algorithm recommends new candidate molecules; these molecules first need to be synthesized and then tested for drug-like properties. The algorithm uses the results of past tests to recommend new ones so as to find good molecules efficiently. Most existing data-driven methods for this problem do not account for sample efficiency and/or fail to enforce realistic constraints on synthesizability. In this work, we explore existing kernels for molecules in the literature as well as propose a novel kernel which views a molecule as a graph. In ChemBO, we implement these kernels in a Gaussian process model. Then we explore the chemical space by traversing possible paths of molecular synthesis. Consequently, our approach provides a proposal synthesis path every time it recommends a new molecule to test, a crucial advantage when compared to existing methods. In our experiments, we demonstrate the efficacy of the proposed approach on several molecular optimization problems.


Computer Vision Applications are Changing the World

#artificialintelligence

Retail innovations like Amazon Go have captured the headlines recently, but over the past few years, Computer Vision applications and technologies have been successfully integrated into the CRM domain, from sales and marketing to customer assistance and retention. Computer Vision can be a force multiplier in retail, providing valuable insights into customer behavior and aiding both upselling and cross selling. It can add essential information to a customer's profile based on visual data from smart telematic devices, a game-changer for insurance and utility companies. It can also help predict issues before they happen, allowing customer care teams to avoid dissatisfaction and churn. When a customer reaches out to a company with a technical or service issue, Computer Vision can effectively route the case to the relevant agent, and help the employee diagnose and resolve the problem much faster than if they were relying on voice or text alone.


How-to Build a High-Impact Deep Learning Model for Tree Identification

#artificialintelligence

I participated in an amazing AI challenge through Omdena's community where we built a classification model for trees to prevent fires and save lives using satellite imagery. Omdena brings together AI enthusiasts from around the world to address real-world challenges through AI models. My primary responsibility was to manage the labeling task team. Afterward, I had the chance to take on another responsibility and build an AI model that delivered results beyond expectations. I am Leo from Rio de Janeiro, Brazil and I m a mechanical aeronautics engineer who currently works as a data scientist and management consultant in Brazil helping several companies to achieve better business results.


Local Trend Inconsistency: A Prediction-driven Approach to Unsupervised Anomaly Detection in Multi-seasonal Time Series

arXiv.org Machine Learning

Abstract--Online detection of anomalies in time series is a key technique in various event-sensitive scenarios such a s robotic system monitoring, smart sensor networks and data center security. However, the increasing diversity of data sources and demands are making this task more challenging than ever . First, the rapid increase of unlabeled data makes supervise d learning no longer suitable in many cases. Second, a great po rtion of time series have complex seasonality features. Third, on -line anomaly detection needs to be fast and reliable. In view of this, we in this paper adopt an unsupervised prediction-dri ven approach on the basis of a backbone model combining a series decomposition part and an inference part. We then propose a novel metric, Local Trend Inconsistency (L TI), along with a detection algorithm that efficiently computes L TI chronolo gically along the series and marks each data point with a score indica ting its probability of being anomalous. The result shows that our scheme outperforms several representative anomaly detection alg orithms in Area Under Curve (AUC) metric with decent time efficiency. While time series data has been ubiquitous before the coming of big data era, a large number of recently emerging technical scenarios like autonomous driving, edge computi ng and Internet of Things (IoT) pose new challenges to the detection of anomalies in this type of data. In the meantime, detection techniques that can provide early, reliable repo rts of anomaly has become crucial for a wide range of systems requiring 24/7 monitoring services. In cloud data centers, for example, a distributed monitoring system usually collects a variety of log data from virtual machine level to cluster lev el on a regular basis and sends them to a central detection module, which needs to analyze the aggregated time series to detect any anomalous events including hardware breakdown, unavailable services and cyber attacks. This requires an on - line detector capable of making reliable detections (i.e., with strong sensitivity and specificity), otherwise it could bri ng about unnecessary cost of maintenance.


Researchers use machine learning technique to rapidly evaluate new transition metal compounds

#artificialintelligence

In recent years, machine learning has been proving a valuable tool for identifying new materials with properties optimized for specific applications. Working with large, well-defined data sets, computers learn to perform an analytical task to generate a correct answer and then use the same technique on an unknown data set. While that approach has guided the development of valuable new materials, they've primarily been organic compounds, notes Heather Kulik Ph.D. '09, an assistant professor of chemical engineering. Kulik focuses instead on inorganic compounds--in particular, those based on transition metals, a family of elements (including iron and copper) that have unique and useful properties. In those compounds--known as transition metal complexes--the metal atom occurs at the center with chemically bound arms, or ligands, made of carbon, hydrogen, nitrogen, or oxygen atoms radiating outward. Transition metal complexes already play important roles in areas ranging from energy storage to catalysis for manufacturing fine chemicals--for example, for pharmaceuticals.


Ensemble Neural Networks (ENN): A gradient-free stochastic method

arXiv.org Machine Learning

Abstract: In this study, an efficient stochastic gradient - free method, the ensemble neural networks (ENN), is developed. In the ENN, the optimization process relies on covariance matrices rather than derivatives. The covariance matrices are calculated by the ensemb le randomized maximum likelihood algorithm (EnRML), which is an inverse modeling method. The ENN is able to simultaneously provide estimations and perform uncertainty quantification since it is built under the Bayesian framework. The ENN is also robust to small training data size because the ensemble of stochastic realizations essentially enlarges the training dataset. This constitutes a desirable characteristic, especially for real - world engineering applications. In addition, the ENN does not require the c alculation of gradients, which enables the use of complicated neuron models and loss functions in neural networks. We experimentally demonstrate benefits of the proposed model, in particular showing that the ENN performs much better than the traditional Ba yesian neural networks (BNN). The EnRML in ENN is a substitution of gradient - based optimization algorithms, which means that it can be directly combined with the feed - forward process in other existing (deep) neural networks, such as convolutional neural ne tworks (CNN) and recurrent neural networks (RNN), broadening future applications of the ENN. Keywords: Inverse modeling, Gradient - free, Uncertainty quantification, Robust to small d ata size, Stochastic method 1. Introduction Artificial neural networks (ANN) are computing systems inspired by biological neural networks that constitute animal brains. ANN is capable of approximating nonlinear functional relationships between input and output variables (Kim et al., 2018). From a ma thematical perspective, a neural network can model any function up to any given precision with a sufficiently large number of basis functions (Cybenko, 1989; Hornik, 1991). In addition, we can even use much smaller models by constructing hierarchy neural n etworks (Delalleau & Bengio, 2011; Gal, 2016). The basic processing elements of neural networks are neurons. A collection of neurons is referred to as a layer, and the collection of interconnected layers forms the neural networks (Kim et al., 2018). A four - layer neural network is illustrated in Figure 1 as an example. In a neuron, the output is calculated by a nonlinear function of the sum of its inputs. The connections between different neurons from adjacent layers are represented by the weights in a model. The weights adjust as learning proceeds, and they represent the strength of the signal at a connection. The nonlinear function is also called the activation function, and the most popular choices are sigmoid, tansig, and ReLU (Li et al., 2015). 2 ANN has bee n widely applied to solving real - world engineering problems, and the following three topics are significant for effective applications .