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51.
52.
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: |
53.
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
54.
The study analyzes variables that influence the water management model based on a simultaneous relationship between competing demands in the Marina Baja of Alicante, using a methodology that directly links together urban and irrigation demands, making them relevant to each other from a socioeconomic point of view. The paper identifies the relevant variables of this model and the agent behaviour in a closed and joint system. It also aims to demonstrate that by considering water demands for different yet simultaneous uses and regarding clean and reclaimed waters as integrated resources, the system could remain in equilibrium without external water supplies. 相似文献
55.
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
56.
José María Moreno-Jiménez Juan Aguarón Jesús Cardeñosa María Teresa Escobar José Luis Salazar Adrián Toncovich Alberto Turón 《Computers in human behavior》2012
Two key aspects of the Knowledge Society are the interconnection between the actors involved in the decision making processes and the importance of the human factor, particularly the citizen’s continuous learning and education. This paper presents a new module devoted to knowledge extraction and diffusion that has been incorporated into a previously developed decision making tool concerning the Internet and related with the multicriteria selection of a discrete number of alternatives (PRIOR-Web). Quantitative and qualitative procedures using data and text mining methods have been employed in the extraction of knowledge. Graphical visualisation tools have been incorporated in the diffusion stage of the methodological approach suggested when dealing with decision making in the Knowledge Society. The resulting collaborative platform is being used as the methodological support for the cognitive democracy known as e-cognocracy. 相似文献
57.
58.
This paper addresses the issue of improving the performance of memory management for real-time Java applications, building upon the real-time specification for Java (RTSJ) from the Real-Time Java Expert Group. In a first step, a collecting dynamic memory solution including both a real-time garbage collector and region-based memory management, is proposed. A thorough analysis of the parameters influencing the performance of write barriers in memory management, together with ways of improvement are then presented. Finally, the implementation of a memory management solution compliant with the RTSJ and integrating the proposed improvements is sketched. 相似文献
59.
A Nadal P Jares M Cazorla PL Fernández X Sanjuan L Hernandez M Pinyol M Aldea C Mallofré J Muntané J Traserra E Campo A Cardesa 《Canadian Metallurgical Quarterly》1997,183(2):156-163
The anti-metastatic effect of Z-100, an immunomodulatory arabinomannan extracted from Mycobacterium tuberculosis, was investigated in mice bearing B16 melanoma cells. Treatment of BF10 mice implanted with high metastatic B16F10 melanoma cells with a 10 mg/kg dose of Z-100 resulted in the reduction of experimental pulmonary metastasis as compared with that of BF10 mice treated with saline. The number of pulmonary metastatic colonies in BF1 mice (mice implanted with low metastatic B16F1 melanoma cells) was greatly increased after the inoculation of CD4+ CD11b+ CD281+ TCR alphabeta+ type 2 T cells (F10-Th2 cells) derived from BF10 mice, while only a few metastatic colonies were demonstrated in lungs of BF1 mice inoculated with naive CD4+ T cells. However, the numbers of metastatic colonies in BF1 mice were not increased when they were inoculated with the F10-Th2 cell fraction derived from Z-100-treated BF10 mice and the generation of F10-Th2 cells in BF10 mice was effectively suppressed by the Z-100 treatment. These results suggest that Z-100 inhibits pulmonary metastasis of B16 melanoma through the regulation of tumor-associated Th2 cells, which are a key cell in the acceleration of tumor metastasis. 相似文献
60.
New stainless steel inserts are developed for fastening sheet molding compound (SMC). Using these molded-in inserts, SMC components can be assembled without protrusions. The inserts consist of two mating surfaces which interlock through the existence of a shoulder male boss and a shoulder female counterbore. Repeated assembly and disassembly can take place without damaging the material being fastened. The strength of the joint, when using these interlocking inserts, is comparable to that when using bolts. Also being investigated is the strength of the joint after being immersed in water for half a month. The difference between the dry and wet strengths for the inserted samples is less than that for the bolted samples. Load versus extension plots show that these particular inserts provide a more rigid joint than a bolted connection. 相似文献