177,805 research outputs found
Mittelmeerpflanzen der Güterbahnhöfe des rhein.-westf. Industriegebietes
No full textvon R. Scheuermann in Dortmun
Single-mode interband cascade lasers emitting below 2.8 μm
No full textFinancial support by the European Commission within the WideLase Seventh Framework Programme Project (Grant Agreement No.: 318798) is gratefully acknowledged.In this work, single-mode distributed feedback (DFB) interband cascade laser (ICL) devices with record short wavelength emission below 2.8 μm are presented. Pulsed measurements based on broad area laser devices with a cavity of 2 mm length and 150 μm width showed threshold current densities of 383 A/cm2 at T = 20 °C and a characteristic temperature T0 of 67 K. Fabricated DFB devices were operated in continuous wave mode at room temperature, with threshold currents of 57 mA and demonstrated side mode suppression ratios of larger than 25 dB. The devices showed current tuning ranges of 7 nm and total (including drive current and temperature) tuning ranges of 12 nm, with respective tuning rates of 21 nm/W, 0.13 nm/mA and 0.29 nm/K. Using the full spectral gain bandwidth of the underlying ICL material, single-mode DFB emission was observed within a wavelength range of 150 nm utilizing different DFB grating periods.Peer reviewe
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
Get PDFBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Comparative Visualization Of Geospatial-Temporal Data
No full textThe amount of online data annotated with geospatial and temporal metadata has grown rapidly in the recent years. Social networks like Flickr and Twitter are popular providers of masses of such data, but are hard to browse. Many systems exist that can show the data’s geospatial distribution in a map widget and their temporal distribution in a time widget, allowing these widgets to become dynamic-query-like filters for data. We present a web application that combines several existing approaches and supports comparison of multiple, potentially large result sets of textual queries in a geospatial and temporal context with extended interaction capabilities. We validate our approach with several case studies and our tool’s learnability in a field experiment
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Letter from R. R. Zellick, Assistant Trust Officer, Anglo California National Bank of San Francisco, to Joseph R. Goodman, October 2, 1942
No full textLetter from R. R. Zellick, Assistant Trust Officer at The Anglo California National Bank of San Francisco, to Joseph R. Goodman, regarding property owned by Dave Tatsuno. Zellick mentions a dispute between current tenants and Tatsuno, and that Tatsuno has asked Goodman to help locate trustworthy tenants.Personal correspondence, organizational records, government documents, publications, and other papers created or collected by Joseph R. Goodman documenting the forced removal and incarceration of Japanese Americans during World War II, as well as organized resistance to incarceration. Included in the collection are records of the Japanese Young Men's Christian Association and the Japanese American Citizens' League in San Francisco, including papers of the Japanese YMCA's executive secretary Lincoln Kanai; Sakai family papers; Goodman's correspondence to and from Japanese American incarcerees, organizations opposing forced removal and incarceration of Japanese Americans, the War Relocation Authority, and others; publications, photographs, and ephemera from the Topaz Relocation Center, where Goodman taught high school; War Relocation Authority records and publications; and newspaper clippings, pamphlets, and reports about forced removal and incarceration created by various government, religious, and civic organizations, in California and nationwide
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Supine fulcrum bending test and in-cast correction of Scheuermann juvenile kyphosis
Get PDFBackground: Patients with Scheuermann disease often require conservative management with a series of corrective casts, followed by anti-kyphotic brace. Flexibility of the kyphosis can be assessed during a supine fulcrum bending test. The aim of the study was to analyze the radiological flexibility of kyphosis and immediate in-cast correction in a series of patients conservatively treated.Methods: Eighty-six adolescents were conservatively treated for Scheuermann disease of thoracic location. Charts of 55 patients, 39 boys and 16 girls, were accessible. The mean age was 14.6±1.6 years. On the lateral full-cassette standing radiograph, the angle of thoracic and lumbar lordosis were measured. The flexibility of kyphosis was assessed on a supine fulcrum bending lateral radiograph. The in-cast kyphosis angle was measured on a standing lateral radiograph.Results: In 18 patients, a mild non-progressive scoliotic curvature was present; it did not exceed a Cobb angle measurement of 25°. The initial kyphosis angle was 59.2°±9.3°. The lordosis angle was 76.3°±9.3°. The kyphosis angle on supine fulcrum bending test was 30.4°±9.7°. The kyphosis angle in the reclining cast was 44.3°±12.5°. There was no correlation between age and the supine bending correction. There was a correlation between the correction obtained with the supine bending test and the immediate correction in the cast (r=0.64, p=0.0012).Conclusions: The reduction of the kyphosis Cobb angle by supine fulcrum bending was 50% on average, while in the cast in standing position, only half of this correction was maintained
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