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The KnowWhereGraph Ontology

arXiv.org Artificial Intelligence

KnowWhereGraph is one of the largest fully publicly available geospatial knowledge graphs. It includes data from 30 layers on natural hazards (e.g., hurricanes, wildfires), climate variables (e.g., air temperature, precipitation), soil properties, crop and land-cover types, demographics, and human health, various place and region identifiers, among other themes. These have been leveraged through the graph by a variety of applications to address challenges in food security and agricultural supply chains; sustainability related to soil conservation practices and farm labor; and delivery of emergency humanitarian aid following a disaster. In this paper, we introduce the ontology that acts as the schema for KnowWhereGraph. This broad overview provides insight into the requirements and design specifications for the graph and its schema, including the development methodology (modular ontology modeling) and the resources utilized to implement, materialize, and deploy KnowWhereGraph with its end-user interfaces and public query SPARQL endpoint.


Extending the Benefits of Parallel Elasticity across Multiple Actuation Tasks: A Geometric and Optimization-Based Approach

arXiv.org Artificial Intelligence

A spring in parallel with an effort source (e.g., electric motor or human muscle) can reduce its energy consumption and effort (i.e., torque or force) depending on the spring stiffness, spring preload, and actuation task. However, selecting the spring stiffness and preload that guarantees effort or energy reduction for an arbitrary set of tasks is a design challenge. This work formulates a convex optimization problem to guarantee that a parallel spring reduces the root-mean-square source effort or energy consumption for multiple tasks. Specifically, we guarantee the benefits across multiple tasks by enforcing a set of convex quadratic constraints in our optimization variables -- the parallel spring stiffness and preload. These quadratic constraints are equivalent to ellipses in the stiffness and preload plane, any combination of stiffness and preload inside the ellipse represents a parallel spring that minimizes effort source or energy consumption with respect to an actuator without a spring. This geometric interpretation intuitively guides the stiffness and preload selection process. We analytically and experimentally prove the convex quadratic function of the spring stiffness and preload. As applications, we analyze the stiffness and preload selection of a parallel spring for a knee exoskeleton using human muscle as the effort source and a prosthetic ankle powered by electric motors. To promote adoption, the optimization and geometric methods are available as supplemental open-source software that can be executed in a web browser.


Tab2KG: Semantic Table Interpretation with Lightweight Semantic Profiles

arXiv.org Artificial Intelligence

Tabular data plays an essential role in many data analytics and machine learning tasks. Typically, tabular data does not possess any machine-readable semantics. In this context, semantic table interpretation is crucial for making data analytics workflows more robust and explainable. This article proposes Tab2KG - a novel method that targets at the interpretation of tables with previously unseen data and automatically infers their semantics to transform them into semantic data graphs. We introduce original lightweight semantic profiles that enrich a domain ontology's concepts and relations and represent domain and table characteristics. We propose a one-shot learning approach that relies on these profiles to map a tabular dataset containing previously unseen instances to a domain ontology. In contrast to the existing semantic table interpretation approaches, Tab2KG relies on the semantic profiles only and does not require any instance lookup. This property makes Tab2KG particularly suitable in the data analytics context, in which data tables typically contain new instances. Our experimental evaluation on several real-world datasets from different application domains demonstrates that Tab2KG outperforms state-of-the-art semantic table interpretation baselines.


Semantic CPPS in Industry 4.0

arXiv.org Artificial Intelligence

Cyber-Physical Systems (CPS) play a crucial role in the era of the 4thIndustrial Revolution. Recently, the application of the CPS to industrial manufacturing leads to a specialization of them referred as Cyber-Physical Production Systems (CPPS). Among other challenges, CPS and CPPS should be able to address interoperability issues, since one of their intrinsic requirement is the capability to interface and cooperate with other systems. On the other hand, to fully realize theIndustry 4.0 vision, it is required to address horizontal, vertical, and end-to-end integration enabling a complete awareness through the entire supply chain. In this context, Semantic Web standards and technologies may have a promising role to represent manufacturing knowledge in a machine-interpretable way for enabling communications among heterogeneous Industrial assets. This paper proposes an integration of Semantic Web models available at state of the art for implementing a5C architecture mainly targeted to collect and process semantic data stream in a way that would unlock the potentiality of data yield in a smart manufacturing environment. The analysis of key industrial ontologies and semantic technologies allows us to instantiate an example scenario for monitoring Overall Equipment Effectiveness(OEE). The solution uses the SOSA ontology for representing the semantic datastream. Then, C-SPARQL queries are defined for periodically carrying out useful KPIs to address the proposed aim.


Computing Machinery and Knowledge

arXiv.org Artificial Intelligence

In this paper, I will examine virtue epistemology from the perspective of a nonhuman artificial intelligence (AI) agent to see whether such agent, computing machine, can be able to know things and to possess knowledge. The aim is to gain insight into what it means for a human agent to know things and to possess knowledge by comparing it to a nonhuman agent in this way. Alan Turing, one of the founding fathers of AI, wrote in his classical paper "Computing Machinery and Intelligence" (Turing, 1950) about machine intelligence and ask whether computing machinery, digital computers, could be said to think or not. The paper also covers the ability for a machine to learn things. Turing's position was that this was possible, maybe not at his time, but that it would be possible by the end of the century. Well, the end of the century has now passed and today there is a big hype around AI and specifically related to machine learning. My intention is to review selected parts from Alan Turing's paper and put it to the test against virtue epistemology to see if our progress in the field of AI has changed anything in relation to the possibility for machines to think and know things. My hypothesis, like that of Alan Turing, is that this is possible. The question is if we are there yet or if we need to wait for another end of the century!


Rule Applicability on RDF Triplestore Schemas

arXiv.org Artificial Intelligence

Rule-based systems play a critical role in health and safety, where policies created by experts are usually formalised as rules. When dealing with increasingly large and dynamic sources of data, as in the case of Internet of Things (IoT) applications, it becomes important not only to efficiently apply rules, but also to reason about their applicability on datasets confined by a certain schema. In this paper we define the notion of a triplestore schema which models a set of RDF graphs. Given a set of rules and such a schema as input we propose a method to determine rule applicability and produce output schemas. Output schemas model the graphs that would be obtained by running the rules on the graph models of the input schema. We present two approaches: one based on computing a canonical (critical) instance of the schema, and a novel approach based on query rewriting. We provide theoretical, complexity and evaluation results that show the superior efficiency of our rewriting approach.


SOSA: A Lightweight Ontology for Sensors, Observations, Samples, and Actuators

arXiv.org Artificial Intelligence

The Sensor, Observation, Sample, and Actuator (SOSA) ontology provides a formal but lightweight general-purpose specification for modeling the interaction between the entities involved in the acts of observation, actuation, and sampling. SOSA is the result of rethinking the W3C-XG Semantic Sensor Network (SSN) ontology based on changes in scope and target audience, technical developments, and lessons learned over the past years. SOSA also acts as a replacement of SSN's Stimulus Sensor Observation (SSO) core. It has been developed by the first joint working group of the Open Geospatial Consortium (OGC) and the World Wide Web Consortium (W3C) on Spatial Data on the Web. In this work, we motivate the need for SOSA, provide an overview of the main classes and properties, and briefly discuss its integration with the new release of the SSN ontology as well as various other alignments to specifications such as OGC's Observations and Measurements (O&M), Dolce-Ultralite (DUL), and other prominent ontologies. We will also touch upon common modeling problems and application areas related to publishing and searching observation, sampling, and actuation data on the Web. The SOSA ontology and standard can be accessed at https://www.w3.org/TR/vocab-ssn/. Keywords: Ontology, Sensor, Observation, Actuator, Linked Data, Web of Things, Internet of Things, Schema.org 1. Introduction and Motivation In their broadest definition sensors detect and react to changes in the environment that directly or indirectly reveal the value of a property. The process of determining this, not necessarily numeric, value is called an observation.


This PSA About Fake News From Barack Obama Is Not What It Appears

#artificialintelligence

"We're entering an era in which our enemies can make it look like anyone is saying anything at any point in time -- even if they would never say those things," says "Obama," his lips moving in perfect sync with his words as they become increasingly bizarre. "So, for instance, they could have me say things like, I don't know, [Black Panther's] Killmonger was right! Or Ben Carson is in the sunken place! Or, how'bout this: Simply, President Trump is a total and complete dipshit." As the video soon reveals, the man speaking is not the former commander-in-chief, but rather Oscar-winning filmmaker Jordan Peele with a warning for viewers about trusting material they encounter online.