Overview
Physics-informed neural networks for PDE-constrained optimization and control
Barry-Straume, Jostein, Sarshar, Arash, Popov, Andrey A., Sandu, Adrian
A fundamental problem in science and engineering is designing optimal control policies that steer a given system towards a desired outcome. This work proposes Control Physics-Informed Neural Networks (Control PINNs) that simultaneously solve for a given system state, and for the optimal control signal, in a one-stage framework that conforms to the underlying physical laws. Prior approaches use a two-stage framework that first models and then controls a system in sequential order. In contrast, a Control PINN incorporates the required optimality conditions in its architecture and in its loss function. The success of Control PINNs is demonstrated by solving the following open-loop optimal control problems: (i) an analytical problem, (ii) a one-dimensional heat equation, and (iii) a two-dimensional predator-prey problem.
Beyond the Hype: A Real-World Evaluation of the Impact and Cost of Machine Learning-Based Malware Detection
Bridges, Robert A., Oesch, Sean, Verma, Miki E., Iannacone, Michael D., Huffer, Kelly M. T., Jewell, Brian, Nichols, Jeff A., Weber, Brian, Beaver, Justin M., Smith, Jared M., Scofield, Daniel, Miles, Craig, Plummer, Thomas, Daniell, Mark, Tall, Anne M.
Attackers use malicious software, known as malware, to steal sensitive data, damage network infrastructure, and hold information for ransom. One of the top priorities for computer security tools is to detect malware and prevent or minimize its impact on both corporate and personal networks. Traditionally, signature-based methods have been used to detect files previously identified as malicious with near perfect precision, but potentially miss newer malware samples. With the advent of self-modifying malware and the rapid increase in novel threats, signature-based methods are insufficient on their own. By generalizing patterns of known benign/malicious training examples, machine learning (ML) exhibits the capability to quickly and accurately classify novel file samples in many research studies [19]. Moreover, ML-based malware research has made the transition from the subject of myriad research efforts to a current mainstay of commercial-off-the-shelf (COTS) malware detectors. Yet, few practical evaluations of COTS ML-based technologies have been conducted. Turning from the academic literature to market reports from commercial companies can provide (for a fee) useful information, specifically, end-user feedback, itemization of all technologies in the antivirus/endpoint detection and response marketplace [17], and even statistics showing the efficacy of the detectors on malware tests [4, 40].
Visual Comparison of Language Model Adaptation
Sevastjanova, Rita, Cakmak, Eren, Ravfogel, Shauli, Cotterell, Ryan, El-Assady, Mennatallah
To appear in IEEE Transactions on Visualization and Computer Graphics. Figure 1: We present a workspace that enables the evaluation and comparison of adapters - lightweight alternatives for language model fine-tuning. After data pre-processing (e.g., embedding extraction), users can select pre-trained adapters, create explanations, and explore model differences through three types of visualizations: Concept Embedding Similarity, Concept Embedding Projection, and Concept Prediction Similarity. The explanations are provided for single models as well as model comparisons. For each explanation, we provide further explanation details, such as the word contexts as well as embedding vectors themselves. Abstract--Neural language models are widely used; however, their model parameters often need to be adapted to the specific domains and tasks of an application, which is time-and resource-consuming. Thus, adapters have recently been introduced as a lightweight alternative for model adaptation. They consist of a small set of task-specific parameters with a reduced training time and simple parameter composition. The simplicity of adapter training and composition comes along with new challenges, such as maintaining an overview of adapter properties and effectively comparing their produced embedding spaces. To help developers overcome these challenges, we provide a twofold contribution. First, in close collaboration with NLP researchers, we conducted a requirement analysis for an approach supporting adapter evaluation and detected, among others, the need for both intrinsic (i.e., embedding similaritybased) and extrinsic (i.e., prediction-based) explanation methods. Second, motivated by the gathered requirements, we designed a flexible visual analytics workspace that enables the comparison of adapter properties. In this paper, we discuss several design iterations and alternatives for interactive, comparative visual explanation methods. Our comparative visualizations show the differences in the adapted embedding vectors and prediction outcomes for diverse human-interpretable concepts (e.g., person names, human qualities).
An Algorithmic Approach to Emergence
Bรฉdard, Charles Alexandre, Bergeron, Geoffroy
Emergence is a concept often referred to in the study of complex systems. Coined in 1875 by the philosopher George H. Lewes in his book Problems of Life and Mind [1], the term has ever since mainly been used in qualitative discussions [2, 3]. In most contexts, emergence refers to the phenomenon by which novel properties arise in a complex system which is composed of a large quantity of simpler subsystems that do not exhibit those novel properties by themselves, but rather through their collective interactions. The following citation from Wikipedia [4] reflects this popular idea: "For instance, the phenomenon of life as studied in biology is an emergent property of chemistry, and psychological phenomena emerge from the neurobiological phenomena of living things". For claims such as the above to have a precise meaning, an objective definition of emergence must be provided. Current definitions are framed around a qualitative evaluation of the "novelty" of properties exhibited by a system with respect
Adaptive Resources Allocation CUSUM for Binomial Count Data Monitoring with Application to COVID-19 Hotspot Detection
Hu, Jiuyun, Mei, Yajun, Holte, Sarah, Yan, Hao
In this paper, we present an efficient statistical method (denoted as "Adaptive Resources Allocation CUSUM") to robustly and efficiently detect the hotspot with limited sampling resources. Our main idea is to combine the multi-arm bandit (MAB) and change-point detection methods to balance the exploration and exploitation of resource allocation for hotspot detection. Further, a Bayesian weighted update is used to update the posterior distribution of the infection rate. Then, the upper confidence bound (UCB) is used for resource allocation and planning. Finally, CUSUM monitoring statistics to detect the change point as well as the change location. For performance evaluation, we compare the performance of the proposed method with several benchmark methods in the literature and showed the proposed algorithm is able to achieve a lower detection delay and higher detection precision. Finally, this method is applied to hotspot detection in a real case study of county-level daily positive COVID-19 cases in Washington State WA) and demonstrates the effectiveness with very limited distributed samples.
A survey of transfer learning for machinery diagnostics and prognostics - Artificial Intelligence Review
In industrial manufacturing systems, failures of machines caused by faults in their key components greatly influence operational safety and system reliability. Many data-driven methods have been developed for machinery diagnostics and prognostics. However, there lacks sufficient labeled data to train a high-performance data-driven model. Moreover, machinery datasets are usually collected from different operation conditions and mechanical components, leading to poor model generalization. To address these concerns, cross-domain transfer learning methods are applied to enhance the feasibility and accuracy of data-driven methods for machinery diagnostics and prognostics.
What is Database Management System (DBMS)?
A Database Management System (DBMS) is a computer software application that enables users to create, manage, and query databases. In addition, it can be used to store data for various purposes, such as tracking customer information or managing inventory. Many different DBMS applications are available today, each with its unique features and capabilities. Therefore, when deciding which database is suitable for your needs, it's essential to understand what these systems do. This blog post will provide an overview of DBMS and highlight some of the key features to look for when choosing one.
A Survey of Ad Hoc Teamwork Research
Mirsky, Reuth, Carlucho, Ignacio, Rahman, Arrasy, Fosong, Elliot, Macke, William, Sridharan, Mohan, Stone, Peter, Albrecht, Stefano V.
Ad hoc teamwork is the research problem of designing agents that can collaborate with new teammates without prior coordination. This survey makes a two-fold contribution: First, it provides a structured description of the different facets of the ad hoc teamwork problem. Second, it discusses the progress that has been made in the field so far, and identifies the immediate and long-term open problems that need to be addressed in ad hoc teamwork.
Fair Machine Learning in Healthcare: A Review
Feng, Qizhang, Du, Mengnan, Zou, Na, Hu, Xia
Benefiting from the digitization of healthcare data and the development of computing power, machine learning methods are increasingly used in the healthcare domain. Fairness problems have been identified in machine learning for healthcare, resulting in an unfair allocation of limited healthcare resources or excessive health risks for certain groups. Therefore, addressing the fairness problems has recently attracted increasing attention from the healthcare community. However, the intersection of machine learning for healthcare and fairness in machine learning remains understudied. In this review, we build the bridge by exposing fairness problems, summarizing possible biases, sorting out mitigation methods and pointing out challenges along with opportunities for the future.
Error Parity Fairness: Testing for Group Fairness in Regression Tasks
Gursoy, Furkan, Kakadiaris, Ioannis A.
The applications of Artificial Intelligence (AI) surround decisions on increasingly many aspects of human lives. Society responds by imposing legal and social expectations for the accountability of such automated decision systems (ADSs). Fairness, a fundamental constituent of AI accountability, is concerned with just treatment of individuals and sensitive groups (e.g., based on sex, race). While many studies focus on fair learning and fairness testing for the classification tasks, the literature is rather limited on how to examine fairness in regression tasks. This work presents error parity as a regression fairness notion and introduces a testing methodology to assess group fairness based on a statistical hypothesis testing procedure. The error parity test checks whether prediction errors are distributed similarly across sensitive groups to determine if an ADS is fair. It is followed by a suitable permutation test to compare groups on several statistics to explore disparities and identify impacted groups. The usefulness and applicability of the proposed methodology are demonstrated via a case study on COVID-19 projections in the US at the county level, which revealed race-based differences in forecast errors. Overall, the proposed regression fairness testing methodology fills a gap in the fair machine learning literature and may serve as a part of larger accountability assessments and algorithm audits.