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71.
Ohne Zusammenfassung 相似文献
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Ohne Zusammenfassung 相似文献
73.
Frank G. Goethals Monique Snoeck Wilfried Lemahieu Jacques Vandenbulcke 《Information Systems Frontiers》2006,8(2):67-79
Enterprises are living things. They constantly need to be (re-)architected in order to achieve the necessary agility, alignment
and integration. This paper gives a high-level overview of how companies can go about doing ‘enterprise architecture’ in the
context of both the classic (isolated) enterprise and the Extended Enterprise. By discussing the goals that are pursued in
an enterprise architecture effort we reveal some basic requirements that can be put on the process of architecting the enterprise.
The relationship between managing and architecting the enterprise is discussed and clarified in the FAD(E)E, the Framework
for the Architectural Development of the (Extended) Enterprise.
Frank G. Goethals completed his Master studies in economics (option informatics), at the Katholieke Universiteit Leuven, Belgium, in 2000.
He is presently researching for a Ph.D. under the theme of `Managing data in the Extended Enterprise'. This research is conducted
at the K.U.Leuven under the guidance of professor J. Vandenbulcke, and is financed by SAP Belgium. Frank has a strong interest
in coordination and dependency theory and Enterprise Architecture.
Monique Snoeck obtained her Ph.D. in May 1995 from The Department of Computer Science of the Katholieke Universiteit Leuven with a thesis
that lays the formal foundations of the object-oriented business modelling method MERODE. Since then she has done further
research in the area of formal methods for object-oriented conceptual modelling. She now is Full Professor with the Management
Information Systems Group of the Faculty of Economics and Applied Economics at the Katholieke Universiteit Leuven in Belgium.
She has been involved in several industrial conceptual modelling projects. Her research interests are object oriented conceptual
modelling, software architecture and software quality.
Wilfried Lemahieu holds a Ph.D. from the Department of Applied Economic Sciences of the Katholieke Universiteit Leuven, Belgium (1999). At
present, he is associate professor at the Management Informatics research group of the Faculty of Economics and Applied Economics.
His teaching includes Database Management, Data Storage Architectures and Management Informatics. His research interests comprise
distributed object architectures and web services, object-relational and object-oriented database systems and hypermedia systems.
Jacques A. Vandenbulcke is professor at the Faculty of Economics and Applied Economics of the Katholieke Universiteit Leuven, Belgium. His main research
interests are in Database management, Data modelling, and Business Information Systems. He is co-ordinator of the Leuven Institute
for Research on Information Systems (LIRIS) and holder of the SAP-chair on ‘Extended enterprise infrastructures’. He is president
of ‘Studiecentrum voor Automatische Informatieverwerking (SAI)’, the largest society for computer professionals in Belgium,
and co-founder of the ‘Production and Inventory Control Society (PICS)’ in Belgium. 相似文献
74.
This article presents gas kinetic calculation methods for the energy transport in hydrogen/ air and methane/ air mixture. The total molecular heat conductivity as well as its various shares are calculated and discussed for a temperature range of 400 to 3500 K and for a pressure of 105 Pa. The variation of the air/ fuel ratio under the conditions of chemical equilibrium is also investigated. As opposed to our previous article, an extension of the Chapman-Knskog method which goes beyond the classical 1st approximation for elastic collisions is applied for the evaluation of suitable calculation methods. This is carried out following the method for strong relaxing thermal nonequilibrium according to Brun. The equations applied in this work are simplified formulations for the proximity to equilibrium. The method for the evaluation of the parameters of the inelastic collision and some chosen results are presented. A discussion of the various shares of the molecular heat conductivity emphasizes the considerable influence of the diffusion and the thermal diffusion processes in fuel/ air mixtures compared to the Fourier heat conductivity. 相似文献
75.
The reproducibility of short tandem repeat (STR) amplification of aDNA extracts is limited by means of formation of artifacts during PCR. One of these artifacts, the so called allelic-dropout (failure of the amplification of alleles), may result in false-homozygote typing of a sample, if genotyping is based on the analysis of a single amplification product. 30 tooth- and bone samples collected from 17 individuals of three burial sites were investigated in a blind test. Using the polymerase chain reaction (PCR) the two independent segregating STR-loci HUMVWA and HUMTH01 were amplified. Corresponding to a mathematical estimation, multiple amplifications of each sample and genelocus were carried out. The results of this genotyping were compared intraindividually. 相似文献
76.
Based on the dispersion model rather than on the conventional pluf-flow model, a method of predicting the transient behaviour of parallel and counterflow heat exchangers is developed, whereby the effects of shell-side flow maldistribution and the finite heat capacities of both fluids, tube bundle and shell are considered. The final solution has been obtained by numerical inversion of the Laplace transform, to determine the transient responses to arbitrary inlet temperature variations. The experiment was carried out in a one pass tube heat exchanger. The comparison between therotical and experimental results is presented and the feasibility of this method is discussed. 相似文献
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Wilfried H. Eppendorfer 《Journal of the science of food and agriculture》1977,28(7):607-614
In experiments with increasing applications of nitrogen to ryegrass, red clover and lucerne grown in pots, freeze-dried plant material with widely varying N-content was obtained. Increasing N-concentrations were associated with increasing nitrate contents which proportionally decreased the concentrations (g/16 g total-N) of all amino acids. Expressed as g amino acid/16 g total-N minus NO3-N, concentrations of all amino acids were closely similar at different N-levels. Differences between the three species ' amino acid composition were negligible except for a lower concentration of lysine in the crude protein of ryegrass and of methionine + cystine in the crude protein of clover and lucerne. In feeding experiments with rats increasing total-N concentrations were generally associated with higher true digestibilities of the crude protein of ryegrass, red clover and lucerne, but slightly lower biological values, especially in red clover. Net crude protein utilisation was increased by increasing total-N concentration in ryegrass, decreased in red clover and unchanged in lucerne. When ranked according to the nutritional value of the crude protein, ryegrass comes first, lucerne second and red clover last. Addition of synthetic methionine to ryegrass and lucerne improved their biological values by 30 and 47% respectively. 相似文献