Text-Mining-Methoden im Semantic Web

Zusammenfassungen: Aufbau, Pflege und Nutzung groβer Wissensdatenbanken erfordern den kombinierten Einsatz menschlicher und maschineller Informationsverarbeitung. Da groβe Teile des menschlichen Wissens in Textform vorliegen, bieten sich Methoden des Text Mining zur Extraktion von Wissensinhalten an. Dieser Artikel behandelt Grundlagen des Text Mining im Kontext des Semantic Web. Methoden des Text Mining werden besprochen, die für die halbautomatische Annotierung von Texten und Textteilen eingesetzt werden, insbesondere Eigennamenerkennung (Named-Entity Recognition), automatische Schlüsselworterkennung (Keyword Recognition), automatische Dokumentenklassifikation, teilautomatisches Erstellen von Ontologien und halbautomatische Faktenerkennung (Fact Recognition, Event Recognition). Es werden auch kritische Hintergrundfragen aufgegriffen. Das Problem der zu hohen Fehlerrate und der zu geringen Performanz automatischer Verfahren wird diskutiert. Zwei Beispiele aus der Praxis werden vorgestellt: Erstens das Forschungsprojekt OntoGene der Universität Zürich, in dem Protein-Protein-Interaktionen als Relationstripel aus der Fachliteratur extrahiert werden, und zweitens ein ontologiebasierter Tag-Recommender, der die manuelle Vergabe von Schlüsselwörtern an Wissensressourcen unterstütz

Lifetime limit from nuclear intra-bunch scattering for high-energy hadron beams

We discuss the possibility and importance of nuclear scattering processes inside a bunched hadron beam. Estimates are presented for the LHC

Spatial Knowledge and Urban Planning (Editorial)

Urban planning is simultaneously shaped by and creates new (spatial) knowledge. The changes in planning culture that have taken place in the last decades - especially the so-called communicative turn in planning in the 1990s - have brought about an increased attention to a growing range of stakeholders of urban development, their interests, logics, and participation in planning as well as the negotiation processes between these stakeholders. However, while this has also been researched in breadth and depth, only scant attention has been paid to the knowledge (claims) of these stakeholders. In planning practice, knowledge, implicit and explicit, has been a highly relevant topic for quite some time: It is discussed how local knowledge can inform urban planning, how experimental knowledge on urban development can be generated in living labs, and what infrastructures can process "big data" and make it usable for planning, to name a few examples. With the thematic issue on "Spatial Knowledge and Urban Planning" we invited articles aiming at exploring the diverse understandings of (spatial) knowledge, and how knowledge influences planning and how planning itself constitutes processes of knowledge generation. The editorial gives a brief introduction to the general topic. Subsequently, abstracts of all articles illustrate what contents the issue has to offer and the specific contribution of each text is carved out. In the conclusion, common and recurring themes as well as remaining gaps and open questions at the interface of spatial knowledge and urban planning are discussed

Spatial knowledge and urban planning

Urban planning is simultaneously shaped by and creates new (spatial) knowledge. The changes in planning culture that have taken place in the last decades—especially the so-called communicative turn in planning in the 1990s—have brought about an increased attention to a growing range of stakeholders of urban development, their interests, logics, and participation in planning as well as the negotiation processes between these stakeholders. However, while this has also been researched in breadth and depth, only scant attention has been paid to the knowledge (claims) of these stakeholders. In planning practice, knowledge, implicit and explicit, has been a highly relevant topic for quite some time: It is discussed how local knowledge can inform urban planning, how experimental knowledge on urban development can be generated in living labs, and what infrastructures can process “big data” and make it usable for planning, to name a few examples. With the thematic issue on “Spatial Knowledge and Urban Planning” we invited articles aiming at exploring the diverse understandings of (spatial) knowledge, and how knowledge influences planning and how planning itself constitutes processes of knowledge generation. The editorial gives a brief introduction to the general topic. Subsequently, abstracts of all articles illustrate what contents the issue has to offer and the specific contribution of each text is carved out. In the conclusion, common and recurring themes as well as remaining gaps and open questions at the interface of spatial knowledge and urban planning are discussed

Towards e+e- --> 3 jets at NNLO by sector decomposition

A method based on sector decomposition has been developed to calculate the double real radiation part of the process e+e- to 3 jets at next-to-next-to-leading order. It is shown in an example that the numerical cancellation of soft and collinear poles works well. The method is flexible to include an arbitrary measurement function in the final Monte Carlo program, such that it allows to obtain differential distributions for different kinds of observables. This is demonstrated by showing 3-, 4- and 5-jet rates at order alpha_s^3 for a subpart of the process.Comment: 14 pages, 4 figure

CGM2, a Member of the Carcinoembryonic Antigen Gene Family is Down- Regulated in Colorectal Carcinomas

We have determined the precise chromosomal location, the exon structure, and the expression pattern of CGM2, a member of the carcinoembryonic antigen (CEA) gene family. CGM2 cDNA was amplified by reverse transcription-polymerase chain reaction (RT/PCR) from the colon adenocarcinoma cell line, LS174T. A defective exon is missing from this cDNA clone, leading to a novel domain organization for the human CEA family with two immunoglobulin-like domains. The derived C-terminal domain predicts that the CGM2 protein is membrane-bound through a glycosyl phosphatidylinositol anchor. RT/PCR analyses identified CGM2 transcripts in mucinous ovarian and colonic adenocarcinomas as well as in adjacent colonic tissue, but not in other tumors including leukocytes from six chronic myeloid leukemia patients. Thus, unlike several other family members, CGM2 is not expressed in granulocytes but reveals a more CEA-like expression pattern. Northern blot analyses identified a 2.5-kilobase CGM2 mRNA that is strongly down-regulated in colonic adenocarcinomas compared with adjacent colonic mucosa, suggesting a possible tumor suppressor function. In addition, a 3.2- kilobase transcript was observed in a number of colon tumors that is not detectable in normal colonic tissue. This mRNA species could represent a tumor-specific CGM2 splice variant

CLIC Final Focus Studies

The CLIC final focus system has been designed based on the local compensation scheme proposed by P. Raimondi and A. Seryi. However, there exist important chromatic aberrations that deteriorate the performance of the system. This paper studies the optimization of the final focus based on the computation of the higher orders of the map using MAD-X and PTC. The use of octupole tail folding to reduce the size of the halo in the locations with aperture limitations is also discussed

Decision Support for IT Investment Projects - A Real Option Analysis Approach Based on Relaxed Assumptions

Managerial flexibilities have to be taken into account in ex-ante decision-making on IT investment projects (ITIPs). In many papers of the IS literature, standard financial option pricing models are used to value such managerial flexibilities. Based on a review of the related literature, the paper critically discusses the assumptions of the most frequently used financial option pricing model, namely the Black–Scholes model, arguing for relaxed assumptions that better represent the characteristics of ITIPs. The authors find that existing real option analysis approaches featured in the IS, Finance, and Economics literature are unable to consider more than two of our relaxed assumptions. Consequently, they present their own approach in form of a simulation model for the valuation of real options in ITIPs which offers a better representation of the characteristics of ITIPs by taking the discounted cash-flows and the runtime to be uncertain as well as the market to be incomplete. Based on these modifications of the Black–Scholes model’s assumptions, it is found that the resulting option value contains idiosyncratic risk that has to be taken into account in ITIP decision making. For the realistic case of risk averse decision makers, the consideration of idiosyncratic risk usually leads to a lower risk-adjusted option value, compared to one calculated by means of the Black–Scholes model. This confirms the perception of managers who feel that financial option pricing models frequently overvalue ITIPs and hence may induce flawed investment decisions

Cloning of the Complete Gene for Carcinoembryonic Antigen

Carcinoembryonic antigen (CEA) is a widely used tumor marker, especially in the surveillance of colonic cancer patients. Although CEA is also present in some normal tissues, it is apparently expressed at higher levels in tumorous tissues than in corresponding normal tissues. As a first step toward analyzing the regulation of expression of CEA at the transcriptional level, we have isolated and characterized a cosmid clone (cosCEA1), which contains the entire coding region of the CEA gene. A close correlation exists between the exon and deduced immunoglobulin-like domain borders. We have determined a cluster of transcriptional starts for CEA and the closely related nonspecific cross-reacting antigen (NCA) gene and have sequenced their putative promoters. Regions of sequence homology are found as far as approximately 500 nucleotides upstream from the translational starts of these genes, but farther upstream they diverge completely. In both cases we were unable to find classic TATA or CAAT boxes at their expected positions. To characterize the CEA and NCA promoters, we carried out transient transfection assays with promoter-indicator gene constructs in the CEA-producing adenocarcinoma cell line SW403, as well as in nonproducing HeLa cells. A CEA gene promoter construct, containing approximately 400 nucleotides upstream from the translational start, showed nine times higher activity in the SW403 than in the HeLa cell line. This indicates that cis-acting sequences which convey cell type-specific expression of the CEA gene are contained within this region