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51.
This paper presents work directed at capturing the entrepreneurial and collaborative activity of university researchers. The Triple Helix points to the emergence of the entrepreneurial university as well as to an increasing overlay of activities in universities, industry and government. This study explores ways in which patent-based metrics could be utilized in a Triple Helix context, and how hybrid indicators could be developed by combining patent with survey data. More specifically, it aims to develop indicators that connect technological inventiveness of university researchers to both funding organizations and users, as well as to entrepreneurial activities by academics. The paper develops a simplified model of the innovation process to benchmark the relevance of the indicators to the Triple Helix. An analysis of Finnish academic patents illustrates that patent data can already provide useful indicators but, on its own, cannot provide information about how academic patents are interconnected with government or industry through funding or utilization links. An exclusive analysis of patents can point to patent concentrations on certain universities, to inventors and assignees, or to potential gaps in translating applied science into industrial technology. However, the patent data had to be combined with an inventor survey in order to relate academic patents more to their Triple Helix environment. The survey indicated that most patented academic inventions are connected to (often publicly funded) scientific research by the inventors and tend to be utilized in large firms rather than in start-up companies founded by academic entrepreneurs. 相似文献
52.
Content This paper is dealing with the power density versus electric field characteristic of microwave-excited discharges on the example of typical CO2 laser gas discharges.The fundamentals of the method are a simple electric equivalent circuit for the excitation structure and the assumption of a fixed reduced electric field intensity within the plasma. This operating field is enforced by the plasma under stationary conditions and can be calculated using an electron balance under consideration of the non-Maxwellian electron energy distribution function. The calculations turn out that c.w. excitation with microwaves is involved with considerable plasma power densities. In the case of the CO2 laser this requires special discharge channel designs for effective gas cooling. Besides a discussion of the plasma characteristic, measurements taken from a microwave applicator are presented and compared to the calculations.
Modellierung mikrowellenangeregter Gasentladungen
Übersicht Der Artikel behandelt die Berechnung der Feldstärke-Leistungsdichte-Kennlinie mikrowellenangeregter Gasentladungen am Beispiel von Entladungen in typischen CO2-Lasergasgemischen. Das Berechnungsverfahren beruht auf einem einfachen, auf die meisten Anregungsstrukturen anwendbaren elektrischen Ersatzschaltbild und der Tatsache einer vom Plasma erzwungenen stationären Brennfeldstärke. Letztere wird über eine Elektronenbilanz unter Berücksichtigung der nicht Maxwell'schen Elektronen-Energieverteilung ermittelt. Es zeigt sich, daß bei einer CW-Anregung mit Mikrowellen hohe Mindestleistungsdichten im Plasma auftreten, wodurch beispielsweise im Fall des CO2-Lasers kein Laserbetrieb ohne sehr effektive Maßnahmen zur Gaskühlung möglich ist.Neben einer Diskussion der Plasmakennlinie werden Vergleichsmessungen an einer konkreten Anregungsstruktur vorgestellt.相似文献
53.
Bourque Paul; Blanchard Louis; Saulnier Jo?l; Vézina Jean 《Canadian Metallurgical Quarterly》1992,24(1):118
Studied the relationship among age, physical health status, and psychic and somatic symptoms of depression among elderly adults. Human Ss: 318 male and female Canadian older adults (aged 65–102 yrs). Information on sociodemographic factors and health status was obtained using the Older American Research Scale, French version, by R. Lefran?ois et al (1988). A French version by P. Bourque and D. Beaudette (1982) of the Beck Depression Inventory was also used. The results were evaluated according to each S's sex, age, institutionalized residence status, and health status. Statistical tests were used. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
Survival of pure and mixed cultures of Yersinia enterocolitica and Escherichia coli in sterile spring water stored at 4 degrees C was evaluated. Y. enterocolitica increased two or three logs during the first 3 weeks of incubation, and at the end of 64 weeks viable cells in numbers corresponding to the initial inoculum level were still detectable. However, after 1 week of incubation, the number of E. coli in water started to decrease and in 13 weeks time no E. coli was detected. More rapid decrease of E. coli was observed in mixed cultures. 相似文献
55.
Droplet formation on Si surfaces bombarded by 10 keV beams from a liquid metal indium ion source has been observed. It has been verified that excess indium is transported in the ion beam, probably in the form of charged droplets. SIMS, SEM and RBS techniques have been used to study the distribution of droplets at the surface. At the specified ion source operating conditions, equilibrium droplet coverage is of the order of 25%. Individual droplets have an average diameter of 0.35 ωm and an average height of 2.2 nm. At a bombardment current density of 0.1 mA cm?2, equilibrium coverage is reached in about 1 s. 相似文献
56.
Auguste Commeyras Hlne Collet Laurent Boiteau Jacques Taillades Odile Vandenabeele‐Trambouze Herv Cottet Jean‐Philippe Biron Raphaël Plasson Louis Mion Olivier Lagrille Herv Martin Franck Selsis Michel Dobrijevic 《Polymer International》2002,51(7):661-665
Addressing the still open question of the prebiotic origin of sequential macromolecules (peptides, nucleic acids) on the primitive Earth, we describe a molecular engine (the primary pump), which works at ambient temperature and continuously generates, elongates and complexifies sequential peptides. This new scenario is based on a cyclic reaction sequence, whose keystep is the activation of amino acids into their N‐carboxyanhydrides (NCA) through nitrosation by NOx. This process could have taken place on tidal beaches; it requires a buffered ocean, emerged land and a nitrosating atmosphere. With the help of geochemical studies and computer simulations of atmosphere photochemistry, we show that the primitive Earth during the Hadean may have satisfied all these requirements. © 2001 Society of Chemical Industry. 相似文献
57.
The ability of human gastrointestinal organisms to transform the trichothecenes 3-acetyldeoxynivalenol and nivalenol was investigated. Samples of human faeces were incubated under anaerobic conditions for 48 h with the toxins. They were then extracted and analysed for trichothecenes and metabolites. 3-Acetyldeoxynivalenol was metabolized to deoxynivalenol during the incubation period. In contrast to what has been reported for other species such as rats, mice and pigs, no de-epoxidated metabolites were detected in the faecal incubates. The toxicological significance of the difference in the intestinal ability to transform trichothecenes between species is unknown. 相似文献
58.
Kurzfassung Die Saltpool-Experimente von OSWALD (1998) und OSWALD & KINZELBACH (2004), im Jahre 1998 an der ETH Zürich ausgeführt, sind exzellente Benchmark-Tests für numerische Simulationsprogramme der dichtevariablen Strömung. Zahlreiche Autoren haben Ergebnisse dazu veröffentlicht. Die kritischen Probleme hierbei sind sowohl die zu dicke Übergangszone von hoher Konzentration an der Sohle der Versuchsbox zum Süßwasser am Top der Box in der Injektionsphase und in der Ruhephase als auch die extrem langen Rechenzeiten.Die Untersuchungen von HÄFNER & BOY (2003a) wurden fortgeführt mit dem erweiterten Code MODCALIF-MST (MODular Flow and CALIbration with Front Limitation algorithm—Multi Species and Temperature). Insbesondere werden Methoden zur Rechenzeitbeschleunigung diskutiert und verifiziert. Durch Nutzung eines algebraischen Multigrid- Gleichungslösers konnte die Rechenzeit um den Faktor 4 verringert werden. Zur Prüfung der Leistungsfähigkeit von MODCALIF-MST wurden die Saltpool Experimente, case 1 und case 2, nachsimuliert und Gitterkonvergenzstudien sowie eine Modellkalibrierung durchgeführt.
Simulation of density-dependent solute transport in groundwater and verification with saltpool experiments
Abstract The Saltpool experiments by OSWALD (1998) and OSWALD & KINZELBACH (2004), carried out in 1998 at the ETH Zurich, are an excellent benchmark test for numerical simulation programmes of the variable-density flow. Numerous authors published results on this subject. Here, critical problems are the thick transition zones from high concentration at the bottom to fresh water at the top of the box in the injection phase and the rest phase (phases 1–2) as well as the extremely long computing time.We have continued the investigations by HÄFNER & BOY (2003a) with the extended code MODCALIF-MST (MODular Flow and CALIbration with Front Limitation algorithm—Multi Species and Temperature) in double porosity porous media. Especially, the methods for code acceleration are discussed and verified. By incorporating the algebraic multigrid package as linear equation solver, computing times could be reduced by a factor of about 4. Simulations, a grid convergence study and a model calibration were carried out for the experiments case 1 and case 2 with MODCALIF.相似文献
59.
Ahmet Ekmekyapar Nizamettin Demirkran Asm Künkül 《Chemical Engineering Research and Design》2008,86(9):1011-1016
Ulexite is an important boron mineral used for the production of boron compounds. The aims of this study are to examine the dissolution kinetics of ulexite in acetic acid solutions, and to present an alternative process to produce boric acid. In order to investigate the dissolution kinetics of ulexite in acetic acid solutions, the concentration of solution, reaction temperature, solid-to-liquid ratio, and particle size were selected as experimental parameters. It was determined that the dissolution rate of ulexite increased with increasing solution concentration and temperature and decreasing particle size and solid-to-liquid ratio. The activation energy of the process was found to be 55.8 kJ/mol. 相似文献
60.
Guimond Serge; Dambrun Micha?l; Michinov Nicolas; Duarte Sandra 《Canadian Metallurgical Quarterly》2003,84(4):697
Social dominance orientation (SDO) has been proposed as an important variable in the explanation of prejudice. We distinguish between three conceptualizations of SDO: SDO as a personality trait (personality model), SDO as a moderator of the effects of situational variables (Person X Situation model), and SDO as a mediator of the effect of social position on prejudice (group socialization model [GSM]). Four studies (N = 1,657) looking at the relations between social positions, SDO, and prejudice in a natural setting and in a laboratory setting provide strong support for the GSM. In contrast to previous correlational findings, there is evidence of a cause (dominant social position), an effect (prejudice increases), and a mediator (SDO). These results suggest new perspectives on the integration of individual and contextual determinants of prejudice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献