Nominalization is a linguistic phenomenon in which events usually described in terms of clauses are expressed in the form of noun phrases. Extracting event structures is an important task in text mining applications. To achieve this goal, clauses are parsed and the argument structure of main verbs are extracted from the parsed results. This kind of preprocessing has been commonly done in the past research. In order to extract event structure from nominalized phrases as well, we need to establish a technique to transform nominalized phrases into clauses. In this paper, we propose a method to transform nominalized phrases into clauses by using corpus-based approach. The proposed method first enumerates possible predicate/argument structures by referring to a nominalized phrase (noun phrase) and makes their ranking based on the frequency of each argument in the corpus. The algorithm based on this method was evaluated using a corpus consisting of 24,626 aviation safety reports in English and it achieved a 78% accuracy in transformation. The algorithm was also evaluated by applying a text mining application to extract events and their cause-effect relations from the texts. This application produced an improvement in the text mining application's performance.

The thickness dependence of structure, magnetic properties and read-write characteristics has been studied for sputtered iron oxide thin films prepared by RF reactive sputtering. For sputter-deposited Fe3O4 films, [111] preferential orientation perpendicular to film surface is improved and crystal size increases with an increase in thickness (δ). Magnetic properties for Fe3O4 films are affected by thickness. In particular, saturation magnetization rapidly decreases at thicknesses less than about 0.07 µm. From this perspective, it is concluded that a thickness larger than about 0.07 µm is available for practical use. For oxidation-annealed γ- Fe2O3 media, signal-output and media transition length are proportional to δ0.7 and δ0.5, respectively. A γ-(Co0.025Cu0.03Fe0.945)2O3 medium with a 0.071 µm thickness shows 0.51 mV of Epp, 2000 frpm of D-6 dB, -35 dB of O/W and 38 dB of SNR.