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A survey, review, and future trends of skin lesion segmentation and classification

arXiv.org Artificial Intelligence

The Computer-aided Diagnosis or Detection (CAD) approach for skin lesion analysis is an emerging field of research that has the potential to alleviate the burden and cost of skin cancer screening. Researchers have recently indicated increasing interest in developing such CAD systems, with the intention of providing a user-friendly tool to dermatologists to reduce the challenges encountered or associated with manual inspection. This article aims to provide a comprehensive literature survey and review of a total of 594 publications (356 for skin lesion segmentation and 238 for skin lesion classification) published between 2011 and 2022. These articles are analyzed and summarized in a number of different ways to contribute vital information regarding the methods for the development of CAD systems. These ways include relevant and essential definitions and theories, input data (dataset utilization, preprocessing, augmentations, and fixing imbalance problems), method configuration (techniques, architectures, module frameworks, and losses), training tactics (hyperparameter settings), and evaluation criteria. We intend to investigate a variety of performance-enhancing approaches, including ensemble and post-processing. We also discuss these dimensions to reveal their current trends based on utilization frequencies. In addition, we highlight the primary difficulties associated with evaluating skin lesion segmentation and classification systems using minimal datasets, as well as the potential solutions to these difficulties. Findings, recommendations, and trends are disclosed to inform future research on developing an automated and robust CAD system for skin lesion analysis.


Metaverse: Requirements, Architecture, Standards, Status, Challenges, and Perspectives

arXiv.org Artificial Intelligence

The Metaverse is driving the next wave of innovation for new opportunities by replacing the digital world (Internet) with the virtual world through a single, shared, immersive, persistent 3D virtual space. In this paper, we present requirements, architecture, standards, challenges, and solutions for Metaverse. Specifically, we provide Metaverse architecture and requirements, and different standards for Metaverse which serve as the basis for the development and deployment. Moreover, we present recent status, challenges such as integration of AI and Metaverse, security and privacy in Metaverse, etc., and perspectives and solutions.


FV-MgNet: Fully Connected V-cycle MgNet for Interpretable Time Series Forecasting

arXiv.org Artificial Intelligence

By investigating iterative methods for a constrained linear model, we propose a new class of fully connected V-cycle MgNet for long-term time series forecasting, which is one of the most difficult tasks in forecasting. MgNet is a CNN model that was proposed for image classification based on the multigrid (MG) methods for solving discretized partial differential equations (PDEs). We replace the convolutional operations with fully connected operations in the existing MgNet and then apply them to forecasting problems. Motivated by the V-cycle structure in MG, we further propose the FV-MgNet, a V-cycle version of the fully connected MgNet, to extract features hierarchically. By evaluating the performance of FV-MgNet on popular data sets and comparing it with state-of-the-art models, we show that the FV-MgNet achieves better results with less memory usage and faster inference speed. In addition, we develop ablation experiments to demonstrate that the structure of FV-MgNet is the best choice among the many variants.


New Linear-time Algorithm for SubTree Kernel Computation based on Root-Weighted Tree Automata

arXiv.org Artificial Intelligence

Tree kernels have been proposed to be used in many areas as the automatic learning of natural language applications. In this paper, we propose a new linear time algorithm based on the concept of weighted tree automata for SubTree kernel computation. First, we introduce a new class of weighted tree automata, called Root-Weighted Tree Automata, and their associated formal tree series. Then we define, from this class, the SubTree automata that represent compact computational models for finite tree languages. This allows us to design a theoretically guaranteed linear-time algorithm for computing the SubTree Kernel based on weighted tree automata intersection. The key idea behind the proposed algorithm is to replace DAG reduction and nodes sorting steps used in previous approaches by states equivalence classes computation allowed in the weighted tree automata approach. Our approach has three major advantages: it is output-sensitive, it is free sensitive from the tree types (ordered trees versus unordered trees), and it is well adapted to any incremental tree kernel based learning methods. Finally, we conduct a variety of comparative experiments on a wide range of synthetic tree languages datasets adapted for a deep algorithm analysis. The obtained results show that the proposed algorithm outperforms state-of-the-art methods.


Online Re-Planning and Adaptive Parameter Update for Multi-Agent Path Finding with Stochastic Travel Times

arXiv.org Artificial Intelligence

This study explores the problem of Multi-Agent Path Finding with continuous and stochastic travel times whose probability distribution is unknown. Our purpose is to manage a group of automated robots that provide package delivery services in a building where pedestrians and a wide variety of robots coexist, such as delivery services in office buildings, hospitals, and apartments. It is often the case with these real-world applications that the time required for the robots to traverse a corridor takes a continuous value and is randomly distributed, and the prior knowledge of the probability distribution of the travel time is limited. Multi-Agent Path Finding has been widely studied and applied to robot management systems; however, automating the robot operation in such environments remains difficult. We propose 1) online re-planning to update the action plan of robots while it is executed, and 2) parameter update to estimate the probability distribution of travel time using Bayesian inference as the delay is observed. We use a greedy heuristic to obtain solutions in a limited computation time. Through simulations, we empirically compare the performance of our method to those of existing methods in terms of the conflict probability and the actual travel time of robots. The simulation results indicate that the proposed method can find travel paths with at least 50% fewer conflicts and a shorter actual total travel time than existing methods. The proposed method requires a small number of trials to achieve the performance because the parameter update is prioritized on the important edges for path planning, thereby satisfying the requirements of quick implementation of robust planning of automated delivery services.


Curriculum-guided Abstractive Summarization for Mental Health Online Posts

arXiv.org Artificial Intelligence

Automatically generating short summaries from users' online mental health posts could save counselors' reading time and reduce their fatigue so that they can provide timely responses to those seeking help for improving their mental state. Recent Transformers-based summarization models have presented a promising approach to abstractive summarization. They go beyond sentence selection and extractive strategies to deal with more complicated tasks such as novel word generation and sentence paraphrasing. Nonetheless, these models have a prominent shortcoming; their training strategy is not quite efficient, which restricts the model's performance. In this paper, we include a curriculum learning approach to reweigh the training samples, bringing about an efficient learning procedure. We apply our model on extreme summarization dataset of MentSum posts -- a dataset of mental health related posts from Reddit social media. Compared to the state-of-the-art model, our proposed method makes substantial gains in terms of Rouge and Bertscore evaluation metrics, yielding 3.5% (Rouge-1), 10.4% (Rouge-2), and 4.7% (Rouge-L), 1.5% (Bertscore) relative improvements.


Multilinear compressive sensing and an application to convolutional linear networks

arXiv.org Artificial Intelligence

We study a deep linear network endowed with a structure. It takes the form of a matrix $X$ obtained by multiplying $K$ matrices (called factors and corresponding to the action of the layers). The action of each layer (i.e. a factor) is obtained by applying a fixed linear operator to a vector of parameters satisfying a constraint. The number of layers is not limited. Assuming that $X$ is given and factors have been estimated, the error between the product of the estimated factors and $X$ (i.e. the reconstruction error) is either the statistical or the empirical risk. In this paper, we provide necessary and sufficient conditions on the network topology under which a stability property holds. The stability property requires that the error on the parameters defining the factors (i.e. the stability of the recovered parameters) scales linearly with the reconstruction error (i.e. the risk). Therefore, under these conditions on the network topology, any successful learning task leads to stably defined features and therefore interpretable layers/network.In order to do so, we first evaluate how the Segre embedding and its inverse distort distances. Then, we show that any deep structured linear network can be cast as a generic multilinear problem (that uses the Segre embedding). This is the {\em tensorial lifting}. Using the tensorial lifting, we provide necessary and sufficient conditions for the identifiability of the factors (up to a scale rearrangement). We finally provide the necessary and sufficient condition called \NSPlong~(because of the analogy with the usual Null Space Property in the compressed sensing framework) which guarantees that the stability property holds. We illustrate the theory with a practical example where the deep structured linear network is a convolutional linear network. As expected, the conditions are rather strong but not empty. A simple test on the network topology can be implemented to test if the condition holds.


Taiwan Parliament speaker says country is a 'beacon of democracy for Chinese-speaking peoples'

FOX News

Hudson Institute senior fellow Michael Pillsbury tells "Fox News @ Night" that war games conducted by the Center for Strategic and International Studies on a Chinese invasion of Taiwan is "all the more reason to try to deter" an invasion. You Si-kun, the speaker of Taiwan's Parliament, spoke at the International Religious Freedom Summit on Wednesday and voiced why it is important that free nations protect Taiwan. "If Taiwan falls into the sphere of influence of CCP (Chinese Communist Party), then the beacon of democracy will be destroyed. And China may invade the first island chain and will cause a threat to the entire world," he said. You Si-kun, the speaker of Taiwan's Parliament, addresses the International Religious Freedom Summit in Washington, D.C. (IRF Summit / Matt Rybczynski) Freedom House's 2022 Freedom in the World report ranked Taiwan a perfect score of 4 concerning religious freedom.


How does AI see your country?. Let's take a Midjourney around the…

#artificialintelligence

If you're not interested in where these images came from, simply scroll past the all the text to view them. Start reading here or watch me make some AI art with OpenAI's DALL·E 2 in the video below. Similar to DALL·E 2, Midjourney is an AI art generator that takes text prompts as input and generates four images per prompt as output. In order to use it, you need a Discord account connected to the Midjourney bot. While this was annoying and took me 10 minutes to set up, I think it's worth the effort. To try it out, you'll type the command /imagine and then enter your prompts directly into a Midjourney newbies channel for free. The downside of the free version is that you get only 25 prompts and you'll keep your eyes glued to the screen while your creations flash by and are lost in a chaotic jumble of results from everyone else who's on the channel with you. Any art you make is also posted publicly on their website under your username and you may use your images under a Creative Commons license as long as you cite Midjourney as the source. There's a lot of joy you can get out of 25 free prompts, but do take a bit of time to see what comes out of other people's prompts so you get the hang of some "prompt engineering" (how to phrase your prompt to get the result you want) before you start, else you might waste your 25 opportunities.


Innov8 Hub Hosts Nigerian Girls Can Code Competition

#artificialintelligence

Innov8 Hub in collaboration with the Nigerian Communication Commission, hosted the maiden edition of the Nigerian Girls Can Code competition. The competition was created for girls in secondary schools across all geopolitical zones in Nigeria. It is strictly made for Nigerian girls interested in the practice and theory of Robotics & Coding. At the opening event, the Communications Advisor at Innov8 Hub, Mr. Deji Ige, gave the opening remark, motivating the girls to achieve the best and dare the impossible. The representative of the NCC, Chinwe Maduabum, welcomed all the participants and their mentors to the competition.