Johannes Keizer
Food and Agriculture Organization
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Publication
Featured researches published by Johannes Keizer.
Semantic Web archive | 2013
Caterina Caracciolo; Armando Stellato; Ahsan Morshed; Gudrun Johannsen; Sachit Rajbhandari; Yves Jaques; Johannes Keizer
Born in the early 1980s as a multilingual agricultural thesaurus, AGROVOC has steadily evolved over the last fifteen years, moving to an electronic version around the year 2000, and embracing the Semantic Web shortly thereafter. Today AGROVOC is a SKOS-XL concept scheme published as Linked Open Data, containing links as well as backlinks and references to many other Linked Datasets in the LOD cloud. In this paper we provide a brief historical summary of AGROVOC and detail its specification as a Linked Dataset.
International Journal of Metadata, Semantics and Ontologies | 2012
Caterina Caracciolo; Armando Stellato; Sachit Rajbahndari; Ahsan Morshed; Gudrun Johannsen; Johannes Keizer; Yves Jaques
The AGROVOC multilingual thesaurus maintained by the Food and Agriculture Organisation (FAO) of the United Nations is now published as linked data. In order to reach this goal AGROVOC was expressed in Simple Knowledge Organisation System (SKOS) and its concepts provided with dereferenceable URIs. AGROVOC is now aligned with ten other multilingual Knowledge Organisation Systems (KOS) related to agriculture, using the SKOS properties exact match and close match. Alignments were automatically produced in Eclipse using a custom-designed tool and then validated by a domain expert. The resulting data is publicly available to both humans and machines using a SPARQL endpoint together with a modified version of Pubby, a lightweight front-end tool for publishing linked data. This paper describes the process that led to the current linked data AGROVOC and discusses current and future applications and directions. This paper extends a shorter version presented at MTSR 2011.
international conference on dublin core and metadata applications | 2002
Boris Lauser; Tanja Wildemann; Allison Poulos; Frehiwot Fisseha; Johannes Keizer; Stephen Katz
This paper presents our ongoing work in establishing a multilingual domain ontology for a biosecurity portal. As a prototypical approach, this project is embedded into the bigger context of the Agricultural Ontology Service (AOS) project of the Food and Agriculture Organization (FAO) of the UN. The AOS will act as a reference tool for ontology creation assistance and herewith enable the transfer of the agricultural domain towards the Semantic Web. The paper focuses on introducing a comprehensive, reusable framework for the process of semi-automatically supported ontology evolvement, which aims to be used in follow-up projects and can eventually be applied to any other domain. Within the multinational context of the FAO, multilingual aspects play a crucial role and therefore an extendable layered ontology modelling approach will be described within the framework. The paper will present the project milestones achieved so far: the creation of a core ontology, the semiautomatic extension of this ontology using a heuristic toolset, and the representation of the resulting ontology in a multilingual web portal. The reader will be provided with a practical example for the creation of a specific domain ontology, which can be applied to any possible domain. Future projects, including automatic text classification, and ontology facilitated search opportunities, will be addressed at the end of the paper.
Library Review | 2008
Margherita Sini; Boris Lauser; Gauri Salokhe; Johannes Keizer; Stephen Katz
Purpose – The main objective of the AGROVOC Concept Server (CS) is to create a collaborative reference platform and a “one‐stop” shop for a pool of commonly used concepts related to agriculture, containing terms, definitions and relationships between terms in multiple languages derived from various sources. This paper aims to address the issues.Design/methodology/approach – The CS offers a centralised facility where the agricultural information management community can build and share agricultural knowledge in a collaborative environment.Findings – The advantages of the CS are its extensibility and modularity that provide the possibility to extend the type of information that can be stored in this system based on user/community needs.Research limitations/implications – Further investigation still needs to be done on the modularisation of the CS (i.e. the creation of separated ontologies that can still be connected, in order to have domain‐related ontologies and to allow for better performance of the CS).P...
european semantic web conference | 2015
Armando Stellato; Sachit Rajbhandari; Andrea Turbati; Manuel Fiorelli; Caterina Caracciolo; Tiziano Lorenzetti; Johannes Keizer; Maria Teresa Pazienza
We introduce VocBench, an open source web application for editing thesauri complying with the SKOS and SKOS-XL standards. VocBench has a strong focus on collaboration, supported by workflow management for content validation and publication. Dedicated user roles provide a clean separation of competences, addressing different specificities ranging from management aspects to vertical competences on content editing, such as conceptualization versus terminology editing. Extensive support for scheme management allows editors to fully exploit the possibilities of the SKOS model, as well as to fulfill its integrity constraints. We discuss thoroughly the main features of VocBench, detail its architecture, and evaluate it under both a functional and user-appreciation ground, through a comparison with state-of-the-art and user questionnaires analysis, respectively. Finally, we provide insights on future developments.
Agricultural Information and Knowledge Management Papers (FAO) | 2010
Tom Baker; Johannes Keizer
FAO, the Food and Agriculture Organization of the UN, has the global goal to defeat hunger and eliminate poverty. One of its core functions is the generation, dissemination and application of information and knowledge. Since 2000, the Agricultural InformationManagement Standards (AIMS) activity in FAO’s Knowledge Exchange and Capacity Building Division has promoted the use of Semantic Web standards to improve information sharing within a global network of research institutes and related partner organizations. The strategy emphasizes the use of simple descriptive metadata, thesauri, and ontologies for integrating access to information from a wide range of sources for both scientific and non-expert audiences. An early adopter of Semantic Web technology, the AIMS strategy is evolving to help information providers in nineteen language areas use modern Linked Data methods to improve the quality of life in developing rural areas, home to seventy percent of the world’s poor and hungry people.
Online Information Review | 2008
Imma Subirats; Irene Onyancha; Gauri Salokhe; Stefka Kaloyanova; Stefano Anibaldi; Johannes Keizer
Purpose – The purpose of this paper is to explore addressing the accessibility, availability and interoperability issues of exchanging agricultural research output by means of the AGRIS application profile – an exchange metadata standard – and controlled vocabularies or subject‐specific knowledge organisation systems.Design/methodology/approach – Based on an analysis of the open access (OA) publishing model and the open archives initiative (OAI), the authors share their proposal for the architecture for open archive networks in agricultural sciences and technology.Findings – The lack of adequate information exchange possibilities between researchers in food and agricultural sciences represents a significant weakness, limiting the research system to properly help address the issues of agricultural development. The OA publishing model promotes the availability of content online, including grey literature, which is not available through commercial distribution channels but which significantly contributes to ...
Journal of Integrative Agriculture | 2012
Sachit Rajbhandari; Johannes Keizer
The Food and Agriculture Organization is developing a concept based multilingual vocabulary management tool to manage thesauri, authority lists and glossaries expressed as concept schemes ready to be used in a linked data environment. In this paper, we described the evolution of the AGROVOC thesaurus to AGROVOC Concept Scheme based on OWL (web ontology language) model and now shifting to SKOS (simple knowledge organization system) model. The paper explained why and how it evolved highlighting the key differences between different models. The system architecture and significant set of features available in the VocBench was discussed in the paper.
metadata and semantics research | 2009
Hilke Stuempel; Gauri Salokhe; Anne Aubert; Johannes Keizer; Andrew Nadeau; Stephen Katz; Stephen Rudgard
Capacity and institution building is a core function of the Food and Agricultural Organization of the United Nations (FAO). FAO has recently started the “Capacity and Institution Building Portal” to provide structured access to information on FAO’s capacity and institution building services and learning resources. To ensure that the Portal can be searched by users and to enable interoperability with other recognized educational repositories, an Application Profile (AP) was created conforming to available and commonly used standards, to describe agricultural learning resources. This article presents the AP, provides an example of an FAO learning resource described and displayed using FAO Learning Resource AP, and presents the lessons learned.
Cataloging & Classification Quarterly | 2007
Anita C. Liang; Gauri Salokhe; Margherita Sini; Johannes Keizer
SUMMARY The semantic heterogeneity of Web information in the Agricultural domain presents tremendous information retrieval challenges. This article presents work taking place at the Food and Agriculture Organizations (FAO) that addresses this challenge. Based on the analysis of resources in the domain of agriculture, this paper proposes (a) an application profile (AP) for dealing with the problem of heterogeneity originating from differences in terminologies, domain coverage, and domain modelling, and (b) a root application ontology (AAO) based on the application profile which can serve as a basis for extending knowledge of the domain. The paper explains how even a small investment in the enhancement of relationships among vocabularies, both metadata and domain-specific, yield a relatively large return on investment.