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71.
Outsourcing der Informationsverarbeitung im Mittelstand: Test eines multitheoretischen Kausalmodells
In this paper determinants of information systems (IS) outsourcing are deduced from transaction cost economic theory, resource-based theory and power theory. They are summarized in a theoretical framework which is tested using a sample of small and medium sized enterprises (SMEs) in Germany. The results show that internal performance and know-how deficits vis-à-vis external service providers are key determinants that explain why different IS functions are outsourced to varying degrees in SMEs. Moreover, the determinants of IS functions were found to partially differ between IS functions. Revised reprint of an article from WIRTSCHAFTSINFORMATIK 43(4)2001:339–350. 相似文献
72.
Prof. Dr. Jarke 《WIRTSCHAFTSINFORMATIK》2009,51(1):154-155
Ohne Zusammenfassung
This article is also available in English via http://www.springerlink.com and http://www.bise-journal.org: BISE – Call for
Papers, Issue 3/2010, High-Impact Requirements Engineering. Bus Inf Syst Eng. doi: . 相似文献
73.
Prof. Dr. Erwin Grochla Direktor Betriebswirtschaftliches Institut für Organisation und Automation an der Universit?t zu
K?ln K?ln Deutschland 《WIRTSCHAFTSINFORMATIK》2009,51(1):104-109
Zusammenfassung Nachdruck eines Aufsatzes aus elektronische datenverarbeitung 11(11)1969:544–548.
This article is also available in English via and : Grochla E (2008) Corporate Information Systems Engineering and Business and Information Systems Engineering as a Necessary
Application-Oriented Extension of General Computer Science – Proposals for Enhancing Academic Education in the Field of Automated
Data Processing in the Federal Republic of Germany. Bus Inf Syst Eng. doi .
相似文献
相似文献
74.
Wirtschaftsinformatik zwischen Wissenschaft und Unternehmertum 总被引:1,自引:1,他引:0
One of the major success indicators for applied research sciences is the rate of transfer from research into practice. Only if concrete and economically successful products are derived from research results, such sciences can induce an impact. However, this process of innovation mandatorily needs entrepreneurship. Within the domain of business information systems, the two German enterprises SAP AG and IDS Scheer AG demonstrate that linking research and innovation is the key to lasting success in the information technology markets. German industry has significant disadvantages on the cost of human resources. Therefore it can be only successful with products that incorporate a high degree of innovation and that are consequently highly priced. But the invention of such products needs scientific research as a source of inspiration. Germany has a highly developed infrastructure of research facilities and organizations. However, they need to be better coordinated and aligned with business needs. Vice versa, enterprises need to actively approach the scientific community in order to clearly formulate their demand. Such a strategy needs changes on all sides. To achieve a change in the domain of science, it is necessary to change the profile of leading researchers, such as full professors. They should incorporate attributes of an entrepreneur and be profiled more as a research manager that tries to anticipate future needs and to develop its unit in terms of research subjects as well as personnel and financial resources. Consequently, the process of application, selection and review of leading researchers should be more oriented on processes that are common in enterprises. E. g. external head-hunters can be involved in the searching and assessing process in order to get the best qualified person for the research vacancy. Also enterprises need to change their attitude towards scientific research. In order to foster this process, executives could be invited to advisory and supervisory boards of research organisations. Furthermore, those executives must be proactively informed about the research activities and results in order to attract their interest and to show potentials for a transfer into products. There is still a long way in the hunt for innovation leadership and all these suggestions can only be a starting point. 相似文献
75.
Li YF Polgar O Okada M Esser L Bates SE Xia D 《Journal of molecular graphics & modelling》2007,25(6):837-851
The ATP-binding cassette protein ABCG2 is a member of a broad family of ABC transporters with potential clinical importance as a mediator of multidrug resistance. We carried out a homology and knowledge-based, and mutationally improved molecular modeling study to establish a much needed structural framework for the protein, which could serve as guidance for further genetic, biochemical, and structural analyses. Based on homology with known structures of both full-length and nucleotide-binding domains (NBD) of ABC transporters and structural knowledge of integral membrane proteins, an initial model of ABCG2 was established. Subsequent refinement to conform to the lipophilic index distributions in the transmembrane domain (TMD) and to the results of site-directed mutagenesis experiments led to an improved model. The complete ABCG2 model consists of two identical subunits facing each other in a closed conformation. The dimeric interface in the nucleotide-binding domain (NBD) involves a characteristic nucleotide sandwich and the interface in the TMD consists of the TM helices 1–3 of one subunit and the helices 5 and 6 of the other. The interface between the NBD and the TMD is bridged by the conserved structural motif between TM2 and TM3, the intracellular domain 1 (ICD1), and the terminal β-strand (S6) of the central β-sheet in the NBD. The apparent flexibility of the ICD1 may play a role in transmitting conformational changes from the NBD to the TMD or from the TMD to the NBD. 相似文献
76.
Masaki Yamamoto 《Theory of Computing Systems》2006,39(5):723-742
A test instance generator (an instance generator for short) for MAX2SAT is a procedure that produces, given a number n of
variables, a 2-CNF formula F of n variables (randomly chosen from some reasonably large domain), and simultaneously provides
one of the optimal solutions for F. We propose an outline to design an instance generator using an expanding graph of a certain
type, called here an "exact 1/2-enlarger". We first show a simple algorithm for constructing an exact 1/2-enlarger, thereby
deriving one concrete polynomial-time instance generator GEN. We also show that an exact 1/2-enlarger can be obtained with
high probability
from graphs randomly constructed. From this fact, we propose another type of instance generator RGEN; it produces a 2-CNF
formula with a solution which is optimal for the formula with high probability. However, RGEN produces less structured formulas
and a much larger class of formulas than GEN. In fact, we prove the NP-hardness of MAX2SAT over the set of 2-CNF formulas
produced by RGEN. 相似文献
77.
Summary This paper presents a unique approach, named mathematical regularization, to remove the nearly-singular and singular integrals occurring in the boundary integral formulations for the solution of the boundary value problems with a pathologica integration boundary due to the very near or coinciding parts of the total boundary. Nonsingular boundary integral equations are derived for thin-walled structure problems. In the case of crack-like problems, we present two kinds of the nonsingular integral representations of the secondary fields and the derivative boundary integral equations. 相似文献
78.
Prof. Dr. P. Albrecht 《Computing》1978,19(3):233-249
The present paper contains a stability concept for discretization methods of a certain, very general classM, which is optimal (in the sense of yielding the best general, two-sided error bounds) without being more restrictive than any of the classical stability definitions. The optimal stability functional Ψh related to it depends on the linear part of the discretization operator, and has the important property that Ψh [δ] may be of orderq+1, i.e. Ψh [δ] = O(h q+1), even if the local error δ only has orderq, δ = O(h q). This result may be used for the construction of methods with maximum order. Its application to linear cyclic methods, for example, furnishes a new approach to the theory of linearM-cyclick-step methods of maximum order. 相似文献
79.
The purpose of this paper is to show that for continuous functions the related quadratic splines converge without any assumption on the spline grid. The points of the interpolatory grid can be chosen between the corresponding points of the spline grid with a division ratio from \(\frac{{\sqrt 2 }}{2}\) to \(1 - \frac{{\sqrt 2 }}{2}\) . In the case of continuously differentiable functions the division ratio can even be taken between 0 and 1; in addition, the order of convergence is increased. For twice differentiable functions the full order of convergence is obtained. Analogous results about the convergence of histo splines are proved. 相似文献
80.
Let the space curveL be defined implicitly by the (n, n+1) nonlinear systemH(u)=0. A new direct Newton-like method for computing turning points ofL is described that requires per step only the evaluation of one Jacobian and 5 function values ofH. Moreover, a linear system of dimensionn+1 with 4 different right hand sides has to be solved per step. Under suitable conditions the method is shown to converge locally withQ-order two if a certain discretization stepsize is appropriately chosen. Two numerical examples confirm the theoretical results. 相似文献