This paper proposes Agriculture Activity Ontology(AAO) as a basis of the core vocabulary of agricultural activity. Since concepts of agriculture activities are formed by the various context such as purpose, means, crop, and eld, we organize the agriculture activity ontology as a hierarchy of concepts discriminated by various properties such as purpose, means, crop and eld. The vocabulary of agricultural activity is then de ned as the subset of the ontology. Since the ontology is consistent, extendable, and capable of some inferences thanks to Description Logics, so the vocabulary inherits these features. It is expected to use in the data format in the agricultural IT system.
The various IT systems have been introduced in farm management to realize better management, i.e., more efficient resource management, ner production control and better product quality. Now data management is indispensable in farm management. Data in farm management is also used in own purpose but the aggregated data is used for statistics, analysis and prediction for area agriculture.
Data in agricultural IT systems is nonetheless not easy to federate and integrate since the languages to describe data are not uni ed. Terminology in agriculture such as names of activity, equipment, and crop has not been well standardized mainly because agriculture has been local. Some of locality comes from diversity of culture and environment and others from the way of business, i.e., farms are small and run independently. But introduction of IT systems changed the situation; farms can be connected beyond the barrier of individual farms, regions, and even culture. But un-uni ed terminology exists as the problem. Without uni ed terminology, smooth data exchange cannot be enabled. So standardization of terminology is the key to enhance agriculture with IT systems.
We focus on agriculture activity in this paper. Agriculture activity is the most basic element of farm management and also the most difficult to standardize since it is more abstract than other types of terminology like equipment and crop. 2
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Agriculture Activity Ontology(AAO) is the basis of the core vocabulary of
agriculture activity, and it provides semantics for agricultural activity names. Also,
AAO is formalized by Description Logics[
The Structuralization of the Agricultural Activities Our strategy to structuralize agricultural activities is the top-down, i.e, starting from the most general activity and expanding it to more speci c activities. The important criteria for the top-down approach is how we can classify more speci c concepts consistently. We de ne more speci c concepts by specifying attributes and their values. We furthermore de ne the general rule for specifying attributes.
We start with the top concept Agriculture Activity which denotes all kind of activities related on crop and/or elds. Then we break down the concept into more concrete concepts. When farmers plan or do a certain agricultural activity, the rst decision is what for they would take the action, i.e., purpose is the rst attribute to distinguish agriculture activities. After the purpose is well speci ed, we use other attributes, i.e., act(type of action), target, place, means, equipment, and season in this order. Crop is also introduced so as to de ne the activity for a speci c crop. These eight attributes are used to de ne the concept and to form the hierarchy of the agricultural activity. For exmaple, Direct seeding in ooded paddy eld can be expressed with DL as follows;
⊓8purpose:seed propagation (1) (2) ⊓8act:sow ⊓8target:seed ⊓8crop:rice ⊓8place:paddy f ield Polysemic Concepts There are many activities conducted for the multiple purposes in the agricultural activities. The typical case is Puddling. it is to plow the bottom of a rice eld, but it is also intended to conduct for the purpose of water retention, i.e., preventing from the water leak, and for the purpose of land leveling, i.e., attening the soil.
⊔Land leveling ⊔Activity f or water retention
In our formalization, these concepts are interpreted as polysemic concept and modelled as disjunction of multiple concepts since none of multiple concepts are mandatory rather optional. The polysemic concepts de ned with multiple concepts can properly express features for the activities conducted for multiple attributions in the Agriculture Activity Ontology.
Reasoning by Agriculture Activity Ontology Since the purpose of AAO is
to keep the agriculture activity terms consistent and well-organized, placing new
terms at the appropriate location in the ontology is mandatory. The main task of
Description Logics is to compute truth value in subsumption checking. However,
it cannot discover subsumers or subsumees for a given subsumee or subsumer
in a given ontological hierarchies. Therefore, we introduced Schank's algorithm
for Case-Based Reasoning(CBR)[
Web Services based on AAO AAO is hosted on CAVOC(Common Agricultural VOCabulary, www.cavoc.org). CAVOC allows browsing and searching concepts of AAO. The key feature of CAVOC is that it provides URIs for names of agriculture activities. In the page, the hierarchical structure is represented in order to indicate the narrower concept, the broader concept, and the relationship between concepts. Also, the data of AAO can be downloaded in the RDF/Turtle formats from cavoc.org/aao/. This format is well supported by many semantic 4 SWCLOS is a lisp-based OWL Full processor on top of Common Lisp Object System (CLOS). It is downloadable from https://github.com/SeijiKoide/SWCLOS. tools, and it is possible to convert it into other RDF formats if needed. Also, we provide a SPARQL endpoint for users to explore AAO data using SPARQL queries. 4
We provide the Agriculture Activity Ontology(AAO) so as to standardize the
vocabulary for agricultural activities. By using the ontology, it is possible to de ne
concepts of agriculture activities beyond the linguistic diversity of the
vocabulary for agricultural activities. The agriculture activity ontology was adopted as
the part of "the guideline for agriculture activity names for agriculture IT
systems" issued by Ministry of Agriculture, Forestry and Fisheries (MAFF), Japan
in 2016, which is one of the achievements of this study[
We are now working to extend our idea to other agriculture domains, i.e., the standardization of vocabulary for agriculture such as the crop, distribution, and agricultural pesticide. Also, international interoperability is next to do. We have already connections with other activities for agricultural ontologies(for example Crop Ontology Group5). Our research has begun from the purpose of establishing the core vocabulary for the eld of agriculture of Japan, although it can be independent regardless of language culture so that it can be applied to various languages and cultures.
This work was supported by Council for Science, Technology and Innovation (CSTI), Cross-ministerial Strategic Innovation Promotion Program(SIP), "Technologies for creating next-generation agriculture, forestry and sheries"(funding agency: Bio-oriented Technology Research Advancement Institution, NARO) 5 https://sites.google.com/a/cgxchange.org/cropontologycommunity/