1,911 research outputs found
An investigation of erosion and deposition of fine cohesive sediments
No full textSIGLEAvailable from British Library Document Supply Centre-DSC:DXN017124 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
On the conceptual feasibility of a CAAD-CAAI integrated decision support system: A computer aided environment for technical decision-making in architecture
No full textArchitectur
Locating Energy Levels of Lanthanide Ions in Inorganic Ionic Compounds
No full textMany phosphors nowadays are lanthanide (Ln) activated semi-conductor and insulator materials due to their serviceable luminescent properties. Few years ago, an empirical model for semi-conductor and insulator materials with an Ln activator has been developed that not only explains the optical properties of phosphors but helps as well to find hitherto unknown materials with selected photoluminescence (PL), thermoluminescence (TL) or charge carrier trapping properties. Within the model, such properties are determined by the locations of the 4f and 5d energy levels of Ln dopant ions relative to the conduction band (CB) and the valence band (VB) of the host. One objective of this project was to localize the Ln 4f levels in different materials relative to the VB and the CB by means of temperature- (T-) dependent PL spectroscopy and (wavelength resolved) TL studies. Another objective was to study possible regularities when going from one type of compound to another one. In this context not only own measured data have been analyzed but also different models have been compared with each other which all aim at explaining the very same phenomenon. For the important class of compounds with formula ABO4:Ln3+ (A = rare earth; B = transition metal, P) it will be shown that the most important charge transfer (CT) energies can be approximated by using always the same approach.Radiation, Radionuclides & ReactorsApplied Science
A letter to A.H. Esq., concerning the stage [electronic resource]
No full textA defense of the stage, in answer to Jeremy Collier's Short view of the immorality and profaneness of the English stage."The initials in the title [i.e. A.H.] have been identified as those of Anthony Hammond. Charles Hopkins has been suggested as the probable author." Cf. NUC pre-1956.Reproduction of original in Huntington Library.WingElectronic reproduction
De kosten van een zandsuppletie op het strand van de Kop van Goeree uitgevoerd met behulp van de zogenaamde "Punaise"
No full textIn het 1e deel van het afstudeerverslag van A.H. van Berk (lit. 1) werd de vraag gesteld of een baggersysteem voor het kustonderhoud van de Kop van Goeree met de punaise (fig. 0) in één van de wingebieden A, B of C (fig. 2) kan konkurreren met een systeem met een cutterzuiger in wingebied E. Voor het antwoord op deze vraag zijn de kosten van zowel de uitvoering met de punaise als die met de cutterzuiger bepaald. Deze kosten zijn omgerekend naar de gemiddelde jaarlijkse kosten voor het kustonderhoud en onderling vergeleken. In het tweede deel wordt een handleiding gegeven voor de berekening van de jaarlijkse kosten van het kustonderhoud van de lop van Goeree door zandsuppietie a.b.v. de Punaise.Hydraulic EngineeringCivil Engineering and Geoscience
Historical Course and Deficiencies of Comparative Interpretation from the 4th to the 6th Century A.H.
No full textComparative studies are the blessed events in the contemporary period that put humanities at the departure point for a dramatic progress. The various branches of religious studies, including the interpretation of the Quran, can be one of the manifestations of such studies. The particular religious thought of the Quran commentators has led to the production of different exegetical products, so that the effect of the two schools of Shi’a and Sunni on the interpretation of some verses - especially theological and jurisprudential verses- is undeniable. Applying a comparative approach in interpreting these two kinds of Quranic verses, while also giving rise to the transparency of the exegetical views of the Shi’a and Sunni commentators, will increase the knowledge of the interpretation and selection of stronger views by Quran exegetes. The present paper seeks to study the beginning of the comparative approach to the interpretation and evolution of it through the study of the most important inferential interpretations of the Fourth, the Fifth and Sixth Centuries. In this essay, some of the most controversial verses among jurisprudents and theologians of Shi’a and Sunni have been selected and the viewpoints of a commentator of a cult in comparison to another cult commentator have been evaluated. The authors of this paper seek to answer the question of what the characteristics are in the comparative approach in the relevant commentaries and what each commentator has looked at, and by what criteria, criticized these views. The results of this research show that with the simultaneously development of two knowledge of theology and jurisprudence in the Middle Centuries A.H, a comparative Shiite-Sunni approach has led to inferential interpretations, and in both schools there has been evolutionary development, and subsequent commentators have compensated for the weaknesses of previous interpreters. Examples that have been examined in this study include points that highlight the strengths and weaknesses of the comparative interpretation, which could be a light for commentators, and a good departure point for interpretive knowledge
Stufenlose hydrostatische Koppelgetriebe fuer Kraftfahrzeuge Auslegung, Gestaltung, Regelung, Vergleiche mit hydrostatischen Standgetrieben, Handschalt- und hydrodynamischen Lastgetrieben
No full textTIB: RN 7998 (1981,5) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman
The structure of a voltage gated potassium channel
No full textVoltage gated potassium channels (Kv channels) are tetrameric ion channels, responsible for regulating the potassium component of the membrane potential in a large range of cell types ranging from mammalian excitable cells to bacteria. Attempts have been made to elucidate the structure of voltage gated potassium channels using X-ray crystallography, however due to the inherent flexibility of the voltage sensors, removal of the channels from their native lipid environment causes distortion of the channels, and as a result much controversy remains over their exact structure. KvAP is a voltage gated potassium channel from the thermophilic archaea Aeropyrum pernix which contains a single cysteine residue, which can be removed by site directed mutagenesis to give a template for cysteine scanning mutagenesis. Fluorescence spectroscopy utilising cysteine reactive probes can be used to probe the membrane topology of proteins in the context of a lipid bilayer. Single cysteine mutants within the pore domain outer helix (S5 helix) of KvAP were generated and labelled with thiol reactive fluorescent probes. These probes were used to report on the polarity of the surrounding environment using a combination of the environmental sensitivity of the probes and fluorescence quenching from both aqueous and lipid phases. Fluorescence results fit well to a hypothetical model describing a trough like variation in dielectric constant of the membrane, allowing the determination of the position of the hydrophobic interface of the membrane at each end of the helix. A mutant of KvAP with no voltage sensing domains was also generated and subjected to cysteine scanning mutagenesis of the S5 helix. Again results fitted well to a hypothetical profile of the dielectric constant of the membrane, and the shift in fluorescence properties at some positions within the helix in the absence of the voltage sensor shows the residues of the pore domain which are in close contact with the voltage sensor
Determinanten van kennisintensieve onderzoeks- en ontwikkelingssamenwerking
No full textIt is becoming increasingly important for companies to ensure a continuing supply of new knowledge. The development of innovative production processes and marketing strategies as well as better products and services improves the competitive position of firms on the world market. This is of special interest to Dutch firms who have only a small and open home market. The principal research question addressed in this thesis concerns the determinants that influence companies in their choice of whether or not to enter into a knowledge-intensive research and development collaboration. This thesis also looks in detail at the role of publicly financed research institutions such as universities, in the setting of the company innovation process as well as at cooperation among private firms. About 13% of all innovative firms in the Netherlands are engaged in some sort of knowledge-intensive research and development collaboration. Knowledge spillovers are an important reason to reject collaboration as a means of acquiring knowledge because spillovers worsen the appropriability conditions, thus decreasing the economic benefits gained from innovative efforts. In correspondence with the literature we find that a high level of R&D-intensity of the partners involved is a very important prerequisite for entering into knowledge intensive R&D-collaboration. Furthermore an important finding is that the probability of entering into a knowledge-intensive R&D-collaboration increases proportionally to the size of the firm. Most innovative firms choose to be engaged in both private and public types of knowledge intensive R&D-collaboration. From this it can be concluded that public and private types of collaboration are complementary to one another. Knowledge intensive R&D-collaboration is also of strategic importance making the decision whether to introduce either improved or newly-developed products onto the market. Firms engaged in knowledge intensive R&D-collaboration more often choose to introduce new products instead of improved products onto the market.Technology, Policy and Managemen
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