6 
InfModel infmodel = ModelFactory.createInfModel(reasoner, m);
Resource vegetarian = infmodel.getResource(source + "Vegetarian");
Resource margherita = infmodel.getResource(source + "Example-Margherita");
if (infmodel.contains(margherita, RDF., vegetarian)) {
        System.out.println("Margherita is a memberOf Vegetarian pizza");
    }

上面给出的例子是由正式的 Pizza.owl 形成的。在这只猫头鹰中，Example-Margherita 是 Margherita 类的个体。所以，它已经写在 owl 文件中了。然而，问题在于推理者应该推断出 margherita-example 也应该是素食披萨。谁能举一个例子来说明如何在 Protege 中找到个人可能的推断类？（Protege 正确推断 Example-Margherita 是素食披萨。但是，我无法以编程方式推断）

4

1 回答 1

10

我解决了我的问题。我认为我的本体有问题。因此，我创建了另一个本体来推断个体。我创建的本体包含 Person 和 Person 的子类：MalePerson、FemalePerson 和 MarriedPerson。并且，有两个对象属性（hasSpouse、hasSibling）和一个数据类型属性（hasAge）。而且，我创建了 3 个个体。John - MalePerson - hasAge(20) - hasSibling(Jane) Jane - FemalePerson - hasSibling(John) - hasSpouse(Bob) Bob - MalePerson - hasSpouse(Jane)

而且，我对 MalePerson 和 FemalePerson 类设置了两个限制。对于 MalePerson : hasSpouse max 1 hasSpouse only MalePerson For FemalePerson : hasSpouse max 1 hasSpouse only FemalePerson

最后，我让 MarriedPerson 成为一个已定义的类。在推理之前，MarriedPerson 没有个体。但是，模型应该推断出 Jane 和 Bob 已婚。因此，最后，MarriedPerson 类应该有 2 个个体。

当我使用 Jena 在 Java 中运行此代码时，我得到了 2 个推断个体。

OntModel ontModel = ModelFactory.createOntologyModel();
    InputStream in = FileManager.get().open(inputFileName);
    if (in == null) {
        throw new IllegalArgumentException( "File: " + inputFileName + " not found");
    }
    ontModel.read(in, "");


    Reasoner reasoner = ReasonerRegistry.getOWLReasoner();
    reasoner = reasoner.bindSchema(ontModel);
    // Obtain standard OWL-DL spec and attach the Pellet reasoner
    OntModelSpec ontModelSpec = OntModelSpec.OWL_DL_MEM;
    ontModelSpec.setReasoner(reasoner);
    // Create ontology model with reasoner support
    OntModel model = ModelFactory.createOntologyModel(ontModelSpec, ontModel);

    // MarriedPerson has no asserted instances
    // However, if an inference engine is used, two of the three
    // individuals in the example presented here will be
    // recognized as MarriedPersons
            //ns is the uri
    OntClass marPerson = model.getOntClass(ns + "OWLClass_00000003866036241880"); // this is the uri for MarriedPerson class
    ExtendedIterator married = marPerson.listInstances();
    while(married.hasNext()) {
        OntResource mp = (OntResource)married.next();
        System.out.println(mp.getURI());
    } // this code returns 2 individuals with the help of reasoner
于 2010-06-12T12:41:44.947 回答