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Visual diagnosis of the Varroa destructor parasitic mite in honeybees using object detector techniques

arXiv.org Artificial Intelligence

The Varroa destructor mite is one of the most dangerous Honey Bee (Apis mellifera) parasites worldwide and the bee colonies have to be regularly monitored in order to control its spread. Here we present an object detector based method for health state monitoring of bee colonies. This method has the potential for online measurement and processing. In our experiment, we compare the YOLO and SSD object detectors along with the Deep SVDD anomaly detector. Based on the custom dataset with 600 ground-truth images of healthy and infected bees in various scenes, the detectors reached a high F1 score up to 0.874 in the infected bee detection and up to 0.727 in the detection of the Varroa Destructor mite itself. The results demonstrate the potential of this approach, which will be later used in the real-time computer vision based honey bee inspection system. To the best of our knowledge, this study is the first one using object detectors for this purpose. We expect that performance of those object detectors will enable us to inspect the health status of the honey bee colonies.


Moreau-Yosida $f$-divergences

arXiv.org Machine Learning

Another is the family of optimal transport central to many machine learning algorithms, with distances (Villani, 2008), including the Wasserstein-1 metric. Lipschitz constrained variants recently gaining In general, variational representations are supremums attention. Inspired by this, we generalize the of integral formulas taken over sets of functions, such as the so-called tight variational representation of f-Donsker-Varadhan formula (Donsker & Varadhan, 1976) divergences in the case of probability measures for the Kullback-Leibler divergence or the Kantorovich-on compact metric spaces to be taken over the Rubinstein formula (Villani, 2008) for the Wasserstein-1 space of Lipschitz functions vanishing at an arbitrary metric. Informally speaking, one can implement (Nowozin base point, characterize functions achieving et al., 2016; Arjovsky et al., 2017) such a formula by constructing the supremum in the variational representation, a real-valued neural network taking samples from propose a practical algorithm to calculate the the two probability measures as inputs, which is then trained tight convex conjugate of f-divergences compatible to maximize the integral formula in order to approximate with automatic differentiation frameworks, the supremum, resulting in a learned proxy to the actual define the Moreau-Yosida approximation of f-divergence of said probability measures. Implementing the divergences with respect to the Wasserstein-1 metric, Kantorovich-Rubinstein formula in such a way involves and derive the corresponding variational formulas, restricting the Lipschitz constant of the neural network (Gulrajani providing a generalization of a number et al., 2017; Petzka et al., 2018; Miyato et al., 2018), of recent results, novel special cases of interest which effectively stabilizes the approximation procedure.


Computer-assisted Venus flytrap captures objects on demand

#artificialintelligence

Exploring new approaches to improve the capabilities and accuracy of robots, a team of researchers in Singapore has turned to an unexpected source: plants. Robots have been dispatched to move cars, lift weighty inventory in warehouses and assist in construction projects. But what if you need to delicately lift a tiny object 1/50th of an inch? To accomplish that task, the Singapore team turned to a Venus flytrap, one of nature's more fascinating plants. The flytrap, a native of North Carolina, contains tiny hairs on two leaf lobes that, when stimulated by an insect, shut tight and slowly devour the prey.


Video gamers say the play to socialize and rarely spend all night glued to the screen, survey finds

Daily Mail - Science & tech

The idea that gamers are antisocial grumps who stay up all night eating junk food while playing Call of Duty in their mother's basement is woefully outdated. According to a new survey, about half of all gamers admit they've been playing more since the pandemic started, but nearly three-quarters use it to socialize. Only ten percent of respondents said they munched on junk while gaming, compared to the 37 percent who don't eat at all while playing. Nearly half of respondents kept their gaming to between 8pm and midnight, while just seven percent burned the midnight oil. UK game developer Jagex first came on the scene in 2001 with RuneScape, a popular fantasy massively multiplayer online roleplaying game (MMORPG).


Unfounded Sets for Disjunctive Hybrid MKNF Knowledge Bases

arXiv.org Artificial Intelligence

Combining the closed-world reasoning of answer set programming (ASP) with the open-world reasoning of ontologies broadens the space of applications of reasoners. Disjunctive hybrid MKNF knowledge bases succinctly extend ASP and in some cases without increasing the complexity of reasoning tasks. However, in many cases, solver development is lagging behind. As the result, the only known method of solving disjunctive hybrid MKNF knowledge bases is based on guess-and-verify, as formulated by Motik and Rosati in their original work. A main obstacle is understanding how constraint propagation may be performed by a solver, which, in the context of ASP, centers around the computation of \textit{unfounded atoms}, the atoms that are false given a partial interpretation. In this work, we build towards improving solvers for hybrid MKNF knowledge bases with disjunctive rules: We formalize a notion of unfounded sets for these knowledge bases, identify lower complexity bounds, and demonstrate how we might integrate these developments into a solver. We discuss challenges introduced by ontologies that are not present in the development of solvers for disjunctive logic programs, which warrant some deviations from traditional definitions of unfounded sets. We compare our work with prior definitions of unfounded sets.


Quantization Algorithms for Random Fourier Features

arXiv.org Machine Learning

The method of random projection (RP) is the standard technique in machine learning and many other areas, for dimensionality reduction, approximate near neighbor search, compressed sensing, etc. Basically, RP provides a simple and effective scheme for approximating pairwise inner products and Euclidean distances in massive data. Closely related to RP, the method of random Fourier features (RFF) has also become popular, for approximating the Gaussian kernel. RFF applies a specific nonlinear transformation on the projected data from random projections. In practice, using the (nonlinear) Gaussian kernel often leads to better performance than the linear kernel (inner product), partly due to the tuning parameter $(\gamma)$ introduced in the Gaussian kernel. Recently, there has been a surge of interest in studying properties of RFF. After random projections, quantization is an important step for efficient data storage, computation, and transmission. Quantization for RP has also been extensive studied in the literature. In this paper, we focus on developing quantization algorithms for RFF. The task is in a sense challenging due to the tuning parameter $\gamma$ in the Gaussian kernel. For example, the quantizer and the quantized data might be tied to each specific tuning parameter $\gamma$. Our contribution begins with an interesting discovery, that the marginal distribution of RFF is actually free of the Gaussian kernel parameter $\gamma$. This small finding significantly simplifies the design of the Lloyd-Max (LM) quantization scheme for RFF in that there would be only one LM quantizer for RFF (regardless of $\gamma$). We also develop a variant named LM$^2$-RFF quantizer, which in certain cases is more accurate. Experiments confirm that the proposed quantization schemes perform well.


Hard negative examples are hard, but useful

arXiv.org Machine Learning

Triplet loss is an extremely common approach to distance metric learning. Representations of images from the same class are optimized to be mapped closer together in an embedding space than representations of images from different classes. Much work on triplet losses focuses on selecting the most useful triplets of images to consider, with strategies that select dissimilar examples from the same class or similar examples from different classes. The consensus of previous research is that optimizing with the \textit{hardest} negative examples leads to bad training behavior. That's a problem -- these hardest negatives are literally the cases where the distance metric fails to capture semantic similarity. In this paper, we characterize the space of triplets and derive why hard negatives make triplet loss training fail. We offer a simple fix to the loss function and show that, with this fix, optimizing with hard negative examples becomes feasible. This leads to more generalizable features, and image retrieval results that outperform state of the art for datasets with high intra-class variance.


Machine Biometrics -- Towards Identifying Machines in a Smart City Environment

arXiv.org Artificial Intelligence

This paper deals with the identification of machines in a smart city environment. The concept of machine biometrics is proposed in this work for the first time, as a way to authenticate machine identities interacting with humans in everyday life. This definition is imposed in modern years where autonomous vehicles, social robots, etc. are considered active members of contemporary societies. In this context, the case of car identification from the engine behavioral biometrics is examined. For this purpose, 22 sound features were extracted and their discrimination capabilities were tested in combination with 9 different machine learning classifiers, towards identifying 5 car manufacturers. The experimental results revealed the ability of the proposed biometrics to identify cars with high accuracy up to 98% for the case of the Multilayer Perceptron (MLP) neural network model.


ZJUKLAB at SemEval-2021 Task 4: Negative Augmentation with Language Model for Reading Comprehension of Abstract Meaning

arXiv.org Artificial Intelligence

This paper presents our systems for the three Subtasks of SemEval Task4: Reading Comprehension of Abstract Meaning (ReCAM). We explain the algorithms used to learn our models and the process of tuning the algorithms and selecting the best model. Inspired by the similarity of the ReCAM task and the language pre-training, we propose a simple yet effective technology, namely, negative augmentation with language model. Evaluation results demonstrate the effectiveness of our proposed approach. Our models achieve the 4th rank on both official test sets of Subtask 1 and Subtask 2 with an accuracy of 87.9% and an accuracy of 92.8%, respectively. We further conduct comprehensive model analysis and observe interesting error cases, which may promote future researches.


On Interpretability and Similarity in Concept-Based Machine Learning

arXiv.org Artificial Intelligence

Machine Learning (ML) provides important techniques for classification and predictions. Most of these are black-box models for users and do not provide decision-makers with an explanation. For the sake of transparency or more validity of decisions, the need to develop explainable/interpretable ML-methods is gaining more and more importance. Certain questions need to be addressed: How does an ML procedure derive the class for a particular entity? Why does a particular clustering emerge from a particular unsupervised ML procedure? What can we do if the number of attributes is very large? What are the possible reasons for the mistakes for concrete cases and models? For binary attributes, Formal Concept Analysis (FCA) offers techniques in terms of intents of formal concepts, and thus provides plausible reasons for model prediction. However, from the interpretable machine learning viewpoint, we still need to provide decision-makers with the importance of individual attributes to the classification of a particular object, which may facilitate explanations by experts in various domains with high-cost errors like medicine or finance. We discuss how notions from cooperative game theory can be used to assess the contribution of individual attributes in classification and clustering processes in concept-based machine learning. To address the 3rd question, we present some ideas on how to reduce the number of attributes using similarities in large contexts.