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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
501

Die Identifikation von Personen mit besonderen Merkmalen. Eine empirische Analyse zur Effizienz der Suchmethode Pyramiding.

Prügl, Reinhard Wilhelm 02 1900 (has links) (PDF)
Die Identifikation von Personen mit hoher Expertise in einem spezifischen Gebiet ist in vielen Bereichen des Wirtschaftslebens von zentraler Bedeutung. Um beispielsweise Marktinformationen einzuholen, wird in Unternehmen normalerweise die Marktforschung bemüht. Deren Instrumentarium ist aus guten Gründen stark am Ideal der Repräsentativität ausgerichtet. Was aber, wenn das Ziel nicht ist, allgemeingültige Aussagen zu gewinnen, sondern seltene, besonders wertvolle Informationen gesucht werden, wie etwa Ideen für neue Produkte? Methoden wird hierzu in der Marktforschungsliteratur kaum Aufmerksamkeit gewidmet. Wissen dazu ist jedoch von hoher Bedeutung. Unternehmen sind einem zunehmenden Innovationsdruck ausgesetzt und daher wird auch die Frage immer wichtiger, wie man zu Ideen für viel versprechende Innovationen gelangen kann. Eine besondere Bedeutung als Träger solcher Ideen haben die so genannten "Lead User" - Produktnutzer, die ihrer Zeit voraus sind. Wie findet man sie? Diese Frage ist keineswegs trivial. Ziel der vorliegenden Arbeit ist es daher, zentrale Fragen bei der Vewendung der Pyramiding-Methode für die Suche nach Personen mit besonderen Merkmalen theoretisch und empirisch zu beantworten. Die beiden Forschungsfragen dieser Dissertation lauten:(1)Wie effizient ist der Suchprozess im Rahmen der Pyramiding-Methode (im Vergleich zur Screening-Methode)? (2)Welche Faktoren beeinflussen die Effizienz eines Verweises der Auskunftsperson bei der Suche mit der Pyramiding-Methode? Ein aufwändiges Feldexperiment ermöglicht die Analyse von 292 Pyramiding-Verweisketten. Das Ergebnis: Im Rahmen der vorliegenden empirischen Untersuchung sind nur zwischen rund 8% und 70% des Aufwands (Anzahl der befragten Personen) für die Suche mittels der Screening-Methode notwendig, um die gesuchte Person zu identifizieren. Als zentrale Einflussfaktoren auf die Effizienz eines Pyramiding-Verweises einer Auskunftsperson konnten in dieser empirischen Untersuchung unterschiedliche Variablen identifiziert und empirisch bestätigt werden: sowohl personenbezogene als auch populationsbezogene Variablen zeigen einen signifikanten Einfluss. (Autorenref.)
502

A study of '2'1'0Pb in the atmosphere and estuarine sedimentary environment

Murdock, Christopher Paul January 1999 (has links)
No description available.
503

Lead in Private Water Wells

Farrell-Poe, Kitt, Jones-McLean, Lisa, McLean, Scott 03 1900 (has links)
2 pp. / 1. Drinking Water Wells; 2. Private Water Well Components; 3. Do Deeper Wells Mean Better Water; 4. Maintaining Your Private Well Water System; 5. Private Well Protection; 6. Well Water Testing and Understanding the Results; 7. Obtaining a Water Sample for Bacterial Analysis; 8. Microorganisms in Private Water Wells; 9. Lead in Private Water Wells; 10. Nitrate in Private Water Wells; 11.Arsenic in Private Water Wells; 12. Matching Drinking Water Quality Problems to Treatment Methods; 13. Commonly Available Home Water Treatment Systems; 14. Hard Water: To Soften or Not to Soften; 15. Shock Chlorination of Private Water Wells / This fact sheet is one in a series of fifteen for private water well owners. The one- to four-page fact sheets will be assembled into a two-pocket folder entitled Private Well Owners Guide. The titles will also be a part of the Changing Rural Landscapes project whose goal is to educate exurban, small acreage residents. The authors have made every effort to align the fact sheets with the proposed Arizona Cooperative Extension booklet An Arizona Well Owners Guide to Water Sources, Quality, Testing, Treatment, and Well Maintenance by Artiola and Uhlman. The private well owner project was funded by both the University of Arizonas Water Sustainability Program-Technology and Research Initiative Fund and the USDA-CSREES Region 9 Water Quality Program.
504

Metal and Metalloid Contaminants in Atmospheric Aerosols from Mining Operations

Csavina, Janae Lynn January 2012 (has links)
Mining operations, including crushing, grinding, smelting, refining, and tailings management, are a significant source of airborne metal and metalloid contaminants such as As, Pb, Cd and other potentially toxic elements. Dust particles emitted from mining operations can accumulate in surrounding soils, natural waters and vegetation at relatively high concentrations through wind and water transport. Human exposure to the dust can occur through inhalation and, especially in the case of children, incidental dust ingestion, particularly during the early years when children are likely to exhibit pica. Furthermore, smelting operations release metals and metalloids in the form of fumes and ultra-fine particulate matter, which disperses more readily than coarser soil dusts. Of specific concern, these fine particulates can be transported to the lungs, allowing contaminants to be transferred into the blood stream. The main aim of this research is to assess the role of atmospheric aerosol and dust in the transport of metal and metalloid contaminants from mining operations to assess the deleterious impacts of these emissions to ecology and human health. In a field campaign, ambient particulates from five mining sites and four reference sites were examined utilizing micro-orifice deposit impactors (MOUDI), total suspended particulate (TSP) collectors, a scanning mobility particle sizer (SMPS), and Dusttrak optical particle counters for an understanding of the fate and transport of atmospheric aerosols. One of the major findings from size-resolved chemical characterization at three mining sites showed that the majority of the contaminant concentrations were found in the fine size fraction (<1 micrometer). Further, metal and metalloids (e.g. As, Cd, and Pb) around smelting activities are significantly enriched in both the coarse and fine size fraction when compared to reference sites. Additionally, with dust events being a growing concern because of predicted climate change and mine tailings being a significant source for dust, high wind conditions around mine tailings were studied for dust generation. Relative humidity was found to play an important predicting role in atmospheric dust concentration. More generally, findings indicate mining activities remain a serious threat to human health and ecology despite the regulations in place to protect from their pollution.
505

FLUID FLOW AND PERMEABILITY OF SOLIDIFYING LEAD-20 WEIGHT PERCENT TIN ALLOYS.

Nasser-Rafi, Rahbar. January 1985 (has links)
No description available.
506

SURFACE ENHANCED RAMAN SCATTERING OF INTERFACIAL HALIDE IONS AND WATER AT SILVER ELECTRODES IN THE PRESENCE OF LEAD (SERS, ADSORPTION, DEPOSITION).

Coria Garcia, Jose Conrado. January 1985 (has links)
No description available.
507

The application of inductively coupled plasma source mass spectrometry to clinical biochemistry and environmental science

Moreton, Jennifer Anne January 1997 (has links)
No description available.
508

Effects of biosolid application to agricultural land on the potential for transport of nutrients (N & P) and heavy contaminants (Cd, Cu, Pb & Zn) in soils

Gove, Lindsey January 2002 (has links)
No description available.
509

Lead tungstate crystal electromagnetic calorimeter in CMS at the large Hadron collider and consequences for physics performance

Graham, Douglas Jonathan January 1998 (has links)
No description available.
510

Structural study of the ferroelectric materials PbNb₂O₆ and PbTa₂O₆

Reeve, William Francis January 1999 (has links)
No description available.

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