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221.
Priv. Doz. Dr. Horst Treiblmaier Univ. Ass. Dr. Andreas Strebinger 《WIRTSCHAFTSINFORMATIK》2006,48(2):87-95
We analyze the influence of B2C e-commerce on IT structure and brand architecture based on conceptual considerations, a case study and an empirical survey. We first discuss the changes in transaction costs that are induced by B2C e-commerce. The effects of B2C e-commerce on IT structure and brand architecture, which are anticipated from a transaction cost perspective, are illustrated using a case study from the tourism industry. We conducted a quantitative study among 101 chief information officers (CIOs) and chief marketing officers (CMOs) from the most important consumer brand companies in Austria. The results of a correspondence analysis show that a high importance of e-commerce triggers a typical bundle of changes in IT structure and brand architecture, which point toward a stronger integration within and between these two structural elements. We therefore conclude that B2C e-commerce calls for a better coordination of those measures that impact IT structure and brand architecture. 相似文献
222.
Dipl.-Wirtsch.-Ing Michael Klafft Dr. rer. pol. Sarah Spiekermann 《WIRTSCHAFTSINFORMATIK》2006,48(1):36-45
Web-based bid invitation platforms and reverse auctions are increasingly used by consumers for the procurement of goods and
services. An empirical examination shows that with B-2-C these procurement methods generate considerable benefits for the
consumer:
相似文献
– | ⊎ Reverse auctions and bid invitation platforms generate high consumer surplus in the procurement of general and crafts services. |
– | ⊎ The level of this consumer surplus is affected by the number of bidders. The duration of the auction and the starting price are less important. |
– | ⊎ In the painting business prices are considerably lower than with traditional procurement channels. |
– | ⊎ On bid invitation platforms, in most cases (> 55%) the bids with the lowest price are chosen. |
223.
Critical success factors revisited: success and failure cases of information systems for senior executives 总被引:1,自引:0,他引:1
The literature suggests the existence of critical success factors (CSFs) for the development of information systems that support senior executives. Our study of six organizations gives evidence for this notion of CSFs. The study further shows an interesting pattern, namely that companies either “get it right”, and essentially succeed on all CSFs, or “get it completely wrong”, that is, fall short on each of the CSFs. Among the six cases for which data were collected through in-depth interviews with company executives, three organizations seemed to manage all the CSFs properly, while two others managed all CSFs poorly. Only one organization showed a mixed scorecard, managing some factors well and some not so well. At the completion of the study, this organization could neither be judged as a success, nor as a failure. This dichotomy between success and failure cases suggests the existence of an even smaller set of “meta-success” factors. Based on our findings, we speculate that these “meta-success” factors are “championship”, “availability of resources”, and “link to organization objectives”. 相似文献
224.
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
225.
Dr.-Ing. B. -J. Brunsbach Univ.-Prof. Dr.-Ing. G. Henneberger Dipl.-Ing. Th. Klepsch 《Electrical Engineering (Archiv fur Elektrotechnik)》1993,76(5):335-341
Mechanische Sensoren zur Drehzahl- und Lageerfassung bei elektrischen Antrieben verursachen Kosten, vergrößern das Bauvolumen des Antriebs, bedingen die Datenübertragung zwischen Regler und Sensor und schränken das Einsatzgebiet des Antriebs ein. Daher wurden verschiedene Konzepte zum Ersatz dieser mechanischen Sensoren entwickelt. Sie unterscheiden sich durch den Aufwand, die benötigte Genauigkeit (Pumpenantrieb Servoantrieb) und dem gewünschten Betriebsbereich.In diesem Beitrag wird die Realisierung des sensorlosen Betriebs einer permanenterregten Synchronmaschine durch ein Kalman-Filter beschrieben. Durch Simulation und durch praktische Untersuchungen konnte gezeigt werden, daß die Schätzung von Lage und Drehzahl die Genauigkeitsanforderungen für eine indirekte Lageregelung erfüllt. Eine solche Lageregelung besitzt keinen mechanischen Sensor mehr. 相似文献
226.
227.
Application of autoregressive spectral analysis to cepstral estimation of mean scatterer spacing 总被引:4,自引:0,他引:4
Wear KA Wagner RF Insana MF Hall TJ 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1993,40(1):50-58
The problem of estimation of mean scatterer spacing in an object containing regularly spaced structures is addressed. An autoregressive (AR) spectral estimation method is compared with a conventional fast Fourier transform (FFT)-based approach for this task. Regularly spaced structures produce a periodicity in the power spectrum of ultrasonic backscatter. This periodicity is manifested as a peak in the cepstrum. A phantom was constructed for comparison of the two methods. It contained regularly spaced nylon filaments. It also contained randomly positioned glass spheres that produced incoherent backscatter. In an experiment in which this target was interrogated using broadband ultrasound, the AR spectral estimate offered considerable improvement over the FFT when the analysis gate length was on the order of the structural dimension. Advantages included improved resolution, reduction in bias and variance of scatterer spacing estimates, and greater resistance to ringing artifacts. Data were also acquired from human liver in vivo. AR spectral estimates on human data exhibited a decreased dependence on gate length. These results offer promise for enhanced spatial resolution and accuracy in ultrasonic tissue characterization and nondestructive evaluation of materials. 相似文献
228.
Dr. habil. N. Van Thoai 《Computing》1993,50(3):241-253
We consider a nonconvex programming problem of minimizing a linear functioncx over a convex setX?? n with an additional constraint ofmultiplicative type \(\prod _{i = 1}^p \psi _i (x) \leqslant 1\) , where the functionsψ i are convex and positive onX. The main idea of our approach is to transform this problem, by usingp additional variables, into acanonical d.c. programming problem with the special structure that thereverse convex constraint involved does only depend on the newly introduced variables. This special structure suggests modifying certain techniques in d.c. programming in a way that the operations handling the nonconvexity are actually performed in the space of the additional variables. The resulting algorithm works very well whenp is small (in comparison withn). 相似文献
229.
Report on highly automated works in Japan — management of labour in line with technology development
In recent years drastic shifts in the paradigms of politics, economics and technologies have occurred throughout the world. The shifts in these three fields are all related. It is our responsibility to investigate these shifts from the aspects of society and mankind for the prosperity of future generations. For this, societies should share with each other their wisdom and knowledge in an effort to plan for the future.Presented at conference on Ecology of Science and Technology, Japan Science Foundation, Tokyo, 1992. 相似文献
230.
The use of information technology to enhance teaching and learning processes has been practiced for a number of years now.
However, the rapid growth in the use of the Internet has led to a new dimension in interactive and collaborative learning
anytime and anyplace dynamically. With the explosion of “virtual education initiatives”, the question of the feasibility and
success criteria for such projects quickly arises. To address the question in an organized way, we propose a project assessment
based on critical success factors. Hence, in this article, we draw on a widely recognized critical success factor framework.
We (slightly) adjust the framework to fit the special characteristics of virtual education initiatives, and apply to one case
study, namely the virtual education initiative at the Faculty of Business at the City University of Hong Kong. The results
suggest that the past success of the case is due to the adherence to the large majority of critical success factors. However,
it also outlines some areas of concern. The paper concludes with a discussion on the strength and limitations of virtual learning
environment as well as future directions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献