Developing ontologies in OWL: An observational study

No abstract

Lifecycle-Support in Architectures for Ontology-Based Information Systems

Ontology-based applications play an increasingly important role in the public and corporate Semantic Web. While today there exist a range of tools and technologies to support specific ontology engineering and management activities, architectural design guidelines for building ontology-based applications are missing. In this paper, we present an architecture for ontology-based applications—covering the complete ontology-lifecycle—that is intended to support software engineers in designing and developing ontology based-applications. We illustrate the use of the architecture in a concrete case study using the NeOn toolkit as one implementation of the architecture

Rotational spectroscopy of mono-deuterated oxirane (cc-C2_2H3_3DO) and its detection towards IRAS 16293−-2422 B

We prepared a sample of mono-deuterated oxirane and studied its rotational spectrum in the laboratory between 490 GHz and 1060 GHz in order to improve its spectroscopic parameters and consequently the calculated rest frequencies of its rotational transitions. The updated rest frequencies were employed to detect $c$-C$_2$H$_3$DO for the first time in the interstellar medium in the Atacama Large Millimetre/submillimetre Array (ALMA) Protostellar Interferometric Line Survey (PILS) of the Class 0 protostellar system IRAS 16293$-$2422. Fits of the detected lines using the rotation diagrams yield a temperature of $T_{\rm rot} = 103 \pm 19$ K, which in turn agrees well with 125 K derived for the $c$-C$_2$H$_4$O main isotopologue previously. The $c$-C$_2$H$_3$DO to $c$-C$_2$H$_4$O ratio is found to be $\sim$0.15 corresponding to a D-to-H ratio of $\sim$0.036 per H atom which is slightly higher than the D-to-H ratio of species such as methanol, formaldehyde, ketene and but lower than those of the larger complex organic species such as ethanol, methylformate and glycolaldehyde. This may reflect that oxirane is formed fairly early in the evolution of the prestellar cores. The identification of doubly deuterated oxirane isotopomers in the PILS data may be possible judged by the amount of mono-deuterated oxirane and the observed trend that multiply deuterated isotopologues have higher deuteration rates than their mono-deuterated variants.Comment: 10 pages total; Mon. Not. R. Astron. Soc., accepte

Rotational spectroscopy of the thioformaldehyde isotopologues H2_2CS and H2_2C34^{34}S in four interacting excited vibrational states and an account on the rotational spectrum of thioketene, H2_2CCS

An investigation of the rotational spectrum of the interstellar molecule thioformaldehyde between 110 and 377 GHz through a pyrolysis reaction revealed a multitude of absorption lines assignable to H$_2$CS and H$_2$C$^{34}$S in their lowest four excited vibrational states besides lines of numerous thioformaldehyde isotopologues in their ground vibrational states reported earlier as well as lines pertaining to several by-products. Additional transitions of H$_2$CS in its lowest four excited vibrational states were recorded in selected regions between 571 and 1386 GHz. Slight to strong Coriolis interactions occur between all four vibrational states with the exception of the two highest lying states because both are totally symmetric vibrations. We present combined analyses of the ground and the four interacting states for our rotational data of H$_2$CS and H$_2$C$^{34}$S. The H$_2$CS data were supplemented with two sets of high-resultion IR data in two separate analyses. The $v_2 = 1$ state has been included in analyses of Coriolis interactions of low-lying fundamental states of H$_2$CS for the first time and this improved the quality of the fits substantially. We extended furthermore assignments in $J$ of transition frequencies of thioketene in its ground vibrational state.Comment: 23 pages including figures, tables, and references; Mol. Phys., accepted (for the Tim Lee memorial issue

SmartWeb: Mobile Access to the Semantic Web

Ankolekar A, Cimiano P, Hitzler P, et al. SmartWeb: Mobile Access to the Semantic Web. In: Wache H, ed. Proceedings of the ESWC2006 poster and demo session. 2006: 3-4

Rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C_4H_9CN) between 2 and 400 GHz

We present high-resolution rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C_4H_9CN). Spectra were taken between 2 and 24 GHz by means of Fourier transform microwave spectroscopy. Spectra between 36 and 403 GHz were recorded by means of frequency modulated (FM) absorption spectroscopy. The analysis yields precise rotational constants and higher order distortion constants, as well as a set of ^(14)N nuclear electric quadrupole coupling parameters for each of the two conformers. In addition, quantum chemical calculations were performed in order to assist the assignments. Frequency calculations yield insight into the vibrational energy structure of the two conformers, from which partition functions and vibrational correction factors are determined. These factors are used to determine experimentally and computationally the energy difference between the two conformers, which is revealed to be negligible. Overall, this study provides precise spectroscopic constants for the search of 3-methylbutyronitrile in the interstellar medium. In particular, this molecule is a perfect test case for our knowledge of branched molecule formation in space