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51.
Information systems (IS) integration is among the most challenging tasks in corporate mergers and acquisitions (M&As). In
this paper we propose and illustrate the use of an approach to analyzing and planning post-merger IS integration that extends
general theory for IS planning, considering the specific characteristics of the M&A context. We highlight that planning effectiveness
is possible to achieve in fundamentally different ways, dependent on the characteristics of the merger or acquisition at hand.
相似文献
Stefan HenningssonEmail: |
52.
António V. Sousa Ana Maria Mendonça Aurélio Campilho 《Pattern Analysis & Applications》2008,11(3-4):409-423
This paper proposes a non-parametric method for the classification of thin-layer chromatographic (TLC) images from patterns represented in a dissimilarity space. Each pattern corresponds to a mixture of Gaussian approximation of the intensity profile. The methodology comprises various phases, including image processing and analysis steps to extract the chromatographic profiles and a classification phase to discriminate among two groups, one corresponding to normal cases and the other to three pathological classes. We present an extensive study of several dissimilarity-based approaches analysing the influence of the dissimilarity measure and the prototype selection method on the classification performance. The main conclusions of this paper are that, Match and Profile-difference dissimilarity measures present better results, and a new prototype selection methodology achieves a performance similar or even better than conventional methods. Furthermore, we also concluded that simplest classifiers, such as k-NN and linear discriminant classifiers (LDCs), present good performance being the overall classification error less than 10% for the four-class problem. 相似文献
53.
Maria Koutantji Peter McCulloch Shabnam Undre Sanjay Gautama Simon Cunniffe Nick Sevdalis Rachel Davis Piers Thomas Charles Vincent Ara Darzi 《Cognition, Technology & Work》2008,10(4):275-285
We developed a module for surgical team training using briefings in simulated crisis scenarios and here we report preliminary
findings. Nine surgical teams (34 trainees) participated in a pre-training simulation, followed by an interactive workshop
on briefing and checklists, and then a post-training simulation. Both technical and non-technical skills were assessed via
observation during simulations by expert trainers who provided feedback on performances at the end of simulation. Trainees
also reported their attitudes to briefings and evaluated the training. Pre-training attitudes to briefing were positive, some
of which improved post-training and trainees’ evaluation of the training was positive. Surgeons’ technical skill improved
significantly post-training, but their decision-making skill was rated lower than other non-technical skills, compared to
other trainees. The training did not appear to greatly improve non-technical skill performance. Training surgical teams in
simulation is feasible but much more work is needed on measurement development and training strategy to confirm its efficacy
and utility. 相似文献
54.
55.
Optimizing multiple dimensional queries simultaneously in multidimensional databases 总被引:1,自引:0,他引:1
Weifa Liang Maria E. Orlowska Jeffrey X. Yu 《The VLDB Journal The International Journal on Very Large Data Bases》2000,8(3-4):319-338
Some significant progress related to multidimensional data analysis has been achieved in the past few years, including the
design of fast algorithms for computing datacubes, selecting some precomputed group-bys to materialize, and designing efficient
storage structures for multidimensional data. However, little work has been carried out on multidimensional query optimization
issues. Particularly the response time (or evaluation cost) for answering several related dimensional queries simultaneously
is crucial to the OLAP applications. Recently, Zhao et al. first exploited this problem by presenting three heuristic algorithms.
In this paper we first consider in detail two cases of the problem in which all the queries are either hash-based star joins
or index-based star joins only. In the case of the hash-based star join, we devise a polynomial approximation algorithm which
delivers a plan whose evaluation cost is $ O(n^{\epsilon }$) times the optimal, where n is the number of queries and is a fixed constant with . We also present an exponential algorithm which delivers a plan with the optimal evaluation cost. In the case of the index-based
star join, we present a heuristic algorithm which delivers a plan whose evaluation cost is n times the optimal, and an exponential algorithm which delivers a plan with the optimal evaluation cost. We then consider
a general case in which both hash-based star-join and index-based star-join queries are included. For this case, we give a
possible improvement on the work of Zhao et al., based on an analysis of their solutions. We also develop another heuristic
and an exact algorithm for the problem. We finally conduct a performance study by implementing our algorithms. The experimental
results demonstrate that the solutions delivered for the restricted cases are always within two times of the optimal, which
confirms our theoretical upper bounds. Actually these experiments produce much better results than our theoretical estimates.
To the best of our knowledge, this is the only development of polynomial algorithms for the first two cases which are able
to deliver plans with deterministic performance guarantees in terms of the qualities of the plans generated. The previous
approaches including that of [ZDNS98] may generate a feasible plan for the problem in these two cases, but they do not provide
any performance guarantee, i.e., the plans generated by their algorithms can be arbitrarily far from the optimal one.
Received: July 21, 1998 / Accepted: August 26, 1999 相似文献
56.
It is argued that robotic platforms are the way forward towards building intelligent systems, where multiple sensors and manipulation are used for cognitive processes. It is also argued that the cue for developing the right architecture for such a system is human language. 相似文献
57.
Cristina Pignotti 《Systems & Control Letters》2012,61(1):92-97
In this paper, we consider the wave equation with internal distributed time delay and local damping in a bounded and smooth domain Ω⊂Rn. When the local damping acts on a neighborhood of a suitable part of the boundary of Ω, we show that an exponential stability result holds if the coefficient of the delay term is sufficiently small. 相似文献
58.
59.
A survey of QoS architectures 总被引:14,自引:0,他引:14
Over the past several years there has been a considerable amount of research within the field of quality-of-service (QoS)
support for distributed multimedia systems. To date, most of the work has been within the context of individual architectural
layers such as the distributed system platform, operating system, transport subsystem and network layers. Much less progress
has been made in addressing the issue of overall end-to-end support for multimedia communications. In recognition of this,
a number of research teams have proposed the development of QoS architectures which incorporate QoS-configurable interfaces
and QoS driven control and management mechanisms across all architectural layers. This paper examines the state-of-the-art
in the development of QoS architectures. The approach taken is to present QoS terminology and a generalized QoS framework
for understanding and discussing QoS in the context of distributed multimedia systems. Following this, we evaluate a number
of QoS architectures that have emerged in the literature. 相似文献
60.
A Peer-to-Peer Approach to Web Service Discovery 总被引:9,自引:0,他引:9
Web Services are emerging as a dominant paradigm for constructing and composing distributed business applications and enabling enterprise-wide interoperability. A critical factor to the overall utility of Web Services is a scalable, flexible and robust discovery mechanism. This paper presents a Peer-to-Peer (P2P) indexing system and associated P2P storage that supports large-scale, decentralized, real-time search capabilities. The presented system supports complex queries containing partial keywords and wildcards. Furthermore, it guarantees that all existing data elements matching a query will be found with bounded costs in terms of number of messages and number of nodes involved. The key innovation is a dimension reducing indexing scheme that effectively maps the multidimensional information space to physical peers. The design and an experimental evaluation of the system are presented. 相似文献