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Key Result (key + result)
Selected AbstractsModelling of paste flows subject to liquid phase migrationINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 10 2007M. J. Patel Abstract Particulate pastes undergoing extrusion can exhibit differential velocities between the solid and liquid phases, termed liquid phase migration (LPM). This is observed experimentally but understanding and predictive capacity for paste and extruder design is limited. Most models for LPM feature one-dimensional analyses. Here, a two-dimensional finite element model based on soil mechanics approaches (modified Cam-Clay) was developed where the liquid and the solids skeleton are treated separately. Adaptive remeshing routines were developed to overcome the significant mesh distortion arising from the large strains inherent in extrusion. Material data to evaluate the model's behaviour were taken from the literature. The predictive capacity of the model is evaluated for different ram velocities and die entry angles (smooth walls). Results are compared with experimental findings in the literature and good qualitative agreement is found. Key results are plots of pressure contributions and extrudate liquid fraction against ram displacement, and maps of permeability, liquid velocity and voids ratio. Pore liquid pressure always dominates extrusion pressure. The relationship between extrusion geometry, ram speed and LPM is complex. Overall, for a given geometry, higher ram speeds give less migration. Pastes flowing into conical entry dies give different voids ratio distributions and do not feature static zones. Copyright © 2007 John Wiley & Sons, Ltd. [source] A review of metal release in the food industryMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 5 2006M. S. Jellesen Abstract The objective of this review is to outline literature on metal release in the food industry. Key results are reviewed from publications with high scientific level as well as papers with focus on industrial aspects. Examples of food products with a corrosive effect are given, and cases concerning processes, storing equipment as well as cleaning and sanitising procedures are reviewed. Stainless steel is the most widely used metallic material in the food industry; however other metals and their alloys are also briefly treated. The review deals with phenomena mainly relating to electrochemical corrosion, but also examples of material degradation as a consequence of wear and corrosive wear are presented. [source] Demand for cash balances in a cashless economyINTERNATIONAL JOURNAL OF ECONOMIC THEORY, Issue 3 2009Richard Dusansky D11; D91; E41 We study the demand for cash balances in the year 2050, when people exclusively use debit cards for all transactions. Money no longer serves as a medium of exchange. However, money still retains its roles as unit of account, numeraire and store of value. We capture these roles in a multi-period model with intertemporal uncertainty regarding prices and the interest rate on bonds, the alternative asset. A key result of our analysis is that the standard negative relationship between money demand and the bond interest rate is seen to be part of a larger economic reality encompassing a broader range of empirically testable implications, including the possibility that the relationship may be positive. We develop formal structural restrictions under which the positive relationship between cash balance demand and the bond interest rate is not only a possible outcome, but an explicit prediction of the model. [source] Price and Nonprice Competition with Endogenous Market StructureJOURNAL OF ECONOMICS & MANAGEMENT STRATEGY, Issue 1 2000George Symeonidis This paper examines the effect of the intensity of short-run price competition and other exogenous variables that affect gross profit margins,such as the degree of product differentiation and the consumers' responsiveness to quality,on market structure and on advertising and R&D expenditure. A key result is that more intense short-run competition can lead to lower concentration in industries with high advertising or R&D intensity, unlike exogenous-sunk-cost industries. Also, price competition has a negative effect on advertising or R&D expenditure. A case study is also presented, which is consistent with the theoretical results of the paper. [source] Die Zweckentfremdung des kommunalen Kassenkredits , eine rechtlich-ökonomische AnalysePERSPEKTIVEN DER WIRTSCHAFTSPOLITIK, Issue 2 2010Christoph Gröpl This development suggests that this debt instrument has been diverted from its original purpose, namely as an instrument of bridging short-run liquidity shortfalls. In this paper we analyze the reasons for this development , from a legal and institutional perspective on the one hand, and from an economic perspective on the other hand. One key result of the analysis is that this development is partly due to the lacking intervention of municipal supervision institutions from the Länder (German Federal States). Obviously, the Länder tolerate the abuse of the Kassenkredit in order to avoid more open types of debt. In addition, we investigate how the introduction of the doubly-entry bookkeeping in the municipalities affects the (improper) use of short-term liquidity credits. Finally, we point to the potential of the municipal Kassenkredit as a loophole in the new German constitutional debt brake. [source] Deformation Driven Homogenization of Fracturing SolidsPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2005Ercan Gürses The paper discusses numerical formulations of the homogenization for solids with discrete crack development. We focus on multi,phase microstructures of heterogeneous materials, where fracture occurs in the form of debonding mechanisms as well as matrix cracking. The definition of overall properties critically depends on the developing discontinuities. To this end, we extend continuous formulations [1] to microstructures with discontinuities [2]. The basic underlying structure is a canonical variational formulation in the fully nonlinear range based on incremental energy minimization. We develop algorithms for numerical homogenization of fracturing solids in a deformation,driven context with non,trivial formulations of boundary conditions for (i) linear deformation and (ii) uniform tractions. The overall response of composite materials with fracturing microstructures are investigated. As a key result, we show the significance of the proposed non,trivial formulation of a traction,type boundary condition in the deformation,driven context. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Src kinase activation: A switched electrostatic networkPROTEIN SCIENCE, Issue 5 2006Elif Ozkirimli Abstract Src tyrosine kinases are essential in numerous cell signaling pathways, and improper functioning of these enzymes has been implicated in many diseases. The activity of Src kinases is regulated by conformational activation, which involves several structural changes within the catalytic domain (CD): the orientation of two lobes of CD; rearrangement of the activation loop (A-loop); and movement of an ,-helix (,C), which is located at the interface between the two lobes, into or away from the catalytic cleft. Conformational activation was investigated using biased molecular dynamics to explore the transition pathway between the active and the down-regulated conformation of CD for the Src-kinase family member Lyn kinase, and to gain insight into the interdependence of these changes. Lobe opening is observed to be a facile motion, whereas movement of the A-loop motion is more complex requiring secondary structure changes as well as communication with ,C. A key result is that the conformational transition involves a switch in an electrostatic network of six polar residues between the active and the down-regulated conformations. The exchange between interactions links the three main motions of the CD. Kinetic experiments that would demonstrate the contribution of the switched electrostatic network to the enzyme mechanism are proposed. Possible implications for regulation conferred by interdomain interactions are also discussed. [source] How buyers frame problems: RevisitedPSYCHOLOGY & MARKETING, Issue 6 2001Elizabeth J. Wilson This article investigates the following propositions: a useful approach for building an organizational-buying,behavior taxonomy might begin with classifying how buyers frame purchasing problems followed by how such frames affect subsequent perceptions and actions in the decision process. Unlike previous taxonomies of buying situations, direct questioning of organizational buyers is used to learn: (1) whether or not they identify different categories of buying problems; (2) if they do, what dimensions they use when framing buying problems; and (3) how do such frames influence their choices of value-added service alternatives offered by suppliers. To test the propositions empirically, supplier choices are modeled with the use of buying-decision exercises. A key result of this study is that the buyers' framing of problems affects their preferences for vendor designs of value-added customer services. Most likely, the framing of buying problems by organizational buyers is layered and more complex than related taxonomies found in the marketing literature. © 2001 John Wiley & Sons, Inc. [source] ROBUST CONTROL FOR A CLASS OF UNCERTAIN STATE-DELAYED SINGULARLY PERTURBED SYSTEMSASIAN JOURNAL OF CONTROL, Issue 2 2005H.R. Karimi ABSTRACT This paper considers the problem of robust control for a class of uncertain state-delayed singularly perturbed systems with norm-bounded nonlinear uncertainties. The system under consideration involves state time-delay and norm-bounded nonlinear uncertainties in the slow state variable. It is shown that the state feedback gain matrices can be determined to guarantee the stability of the closed-loop system for all , , (0, ,00) and independently of the time-delay. Based on this key result and some standard Riccati inequality approaches for robust control of singularly perturbed systems, a constructive design procedure is developed. We present an illustrative example to demonstrate the applicability of the proposed design approach. [source] From Bismarck to FriedmanECONOMIC AFFAIRS, Issue 2 2007Kristian Niemietz Chile provides the most frequently quoted example of a change from an established state PAYGO pension system to a privately funded scheme based on personal savings. Most of the key results have been impressive and a lot of the often-heard criticisms of funded schemes have been disproved. A number of shortcomings remain. These shortcomings are seldom caused by features inherent to funded schemes, but rather by elements specific to the Chilean arrangement which could be altered given the political will. [source] Linking Product Development Outcomes to Market Valuation of the Firm: The Case of the U.S. Pharmaceutical Industry,THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 5 2004Anurag Sharma The purpose of this research was to examine empirically the effects of new product development outcomes on overall firm performance. To do so, first product development and finance literature were connected to develop three testable hypotheses. Next, an event study was conducted in order to explore whether the changes in the stock market valuation of firms are influenced by the outcomes of efforts to develop new products. The pharmaceutical industry was chosen as the empirical context for the present study's analysis largely because the gate-keeping role played by the Food and Drug Administration (FDA) provides a specific event date on which to focus the event study methodology. As such, this study's events were dates of public announcements of the FDA decisions to approve or to reject the New Drug Applications submitted by the sponsoring firms. Consistent with the efficient market hypothesis, this study's results show that market valuations are responsive strongly and cleanly to the success or failure of new product development efforts. Hence, one of this study's key results suggests that financial markets may be attuned sharply to product development outcomes in publicly traded firms. This study also finds that financial market losses from product development failures were much larger in magnitude than financial market gains from product development successes,indicating an asymmetry in the response of financial markets to the success and failure of new product development efforts. Hence, another implication of this study's results is that managers should factor in a substantial risk premium when considering substantial new development projects. The present study's results also imply that managers should refrain from hyping new products and perhaps even should restrain the enthusiasm that the financial community may build before the product fully is developed. The effect on firm value is severe when expectations about an anticipated new product are not fulfilled. Managers in effect should take care to build reasonable and realistic expectations about potential new products. [source] | |||||||||||||