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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
191.
David Wastell 《欧洲信息系统杂志》2010,19(4):422-431
In response to anxieties about our discipline's decline, this opinion piece ‘looks to the future’, arguing a strong prospectus for the IS field, based on its direct relevance to general management practice. The thesis set out is inspired by the recent upsurge in interest in ‘managing as designing’. Reformulating management as design, I argue that we have a formidable knowledge-base of tools, theories and critique relevant to any manager, not just the MIS-inclined specialist. A case study of yet another failed information system (in U.K. children's services) is presented to show just how uniquely relevant our discipline is, in the workplace of today. Other pertinent issues are explored, such as synergies with the growing vogue for evidence-based management. The paper concludes by considering implications for research, including the need for a less exclusive approach to publishing and dissemination emphasising the need to make our work more accessible to lay practitioners. 相似文献
192.
In a number of prior papers we described and explored a new pattern recognition method called Margin-Setting that accomplishes
excellent generalization using very few training samples. The result was a multi-round classifier with each round consisting
of a set of hyperspheres such that if a datum fell within a certain hypersphere, it was labeled with one particular class.
Margin-Setting achieves concurrent low Vapnik-Chervonenkis (VC) dimension and high accuracy which is a consequence of partitioning
the training set into smaller sets that make this possible. This paper extends Margin-Setting from hyperspheres to hyperellipsoids
resulting in improved performance. 相似文献
193.
AND/OR search spaces accommodate advanced algorithmic schemes for graphical models which can exploit the structure of the
model. We extend and evaluate the depth-first and best-first AND/OR search algorithms to solving 0-1 Integer Linear Programs (0-1 ILP) within this framework. We also include a class
of dynamic variable ordering heuristics while exploring an AND/OR search tree for 0-1 ILPs. We demonstrate the effectiveness
of these search algorithms on a variety of benchmarks, including real-world combinatorial auctions, random uncapacitated warehouse
location problems and MAX-SAT instances. 相似文献
194.
Knowledge of the information goal of users is critical in website design, analyzing the efficacy of such designs, and in ensuring effective user-access to
desired information. Determining the information goal is complex due to the subjective and latent nature of user information
needs. This challenge is further exacerbated in media-rich websites since the semantics of media-based information is context-based
and emergent. A critical step in determining information goals lies in the identification of content pages. These are the pages which contain the information the user seeks. We propose a method to automatically determine the content
pages by taking into account the organization of the web site, the media-based information content, as well as the influence
of a specific user browsing pattern. Given a specific browsing pattern, in our method, putative content pages are identified
as the pages corresponding to the local minima of page-content entropy values. For an (unknown) user information goal this
intuitively corresponds to modeling the progressive transition of the user from pages with generic information to those with
specific information. Experimental investigations on media rich sites demonstrate the effectiveness of the technique and underline
its potential in modeling user information needs and actions in a media-rich web. 相似文献
195.
Fuzzy grey relational analysis for software effort estimation 总被引:1,自引:1,他引:0
Accurate and credible software effort estimation is a challenge for academic research and software industry. From many software
effort estimation models in existence, Estimation by Analogy (EA) is still one of the preferred techniques by software engineering
practitioners because it mimics the human problem solving approach. Accuracy of such a model depends on the characteristics
of the dataset, which is subject to considerable uncertainty. The inherent uncertainty in software attribute measurement has
significant impact on estimation accuracy because these attributes are measured based on human judgment and are often vague
and imprecise. To overcome this challenge we propose a new formal EA model based on the integration of Fuzzy set theory with
Grey Relational Analysis (GRA). Fuzzy set theory is employed to reduce uncertainty in distance measure between two tuples
at the k
th
continuous feature ( | ( xo(k) - xi(k) | ) \left( {\left| {\left( {{x_o}(k) - {x_i}(k)} \right.} \right|} \right) .GRA is a problem solving method that is used to assess the similarity between two tuples with M features. Since some of these features are not necessary to be continuous and may have nominal and ordinal scale type, aggregating
different forms of similarity measures will increase uncertainty in the similarity degree. Thus the GRA is mainly used to
reduce uncertainty in the distance measure between two software projects for both continuous and categorical features. Both
techniques are suitable when relationship between effort and other effort drivers is complex. Experimental results showed
that using integration of GRA with FL produced credible estimates when compared with the results obtained using Case-Based
Reasoning, Multiple Linear Regression and Artificial Neural Networks methods. 相似文献
196.
In this paper, the dynamic behaviors of a class of neural networks with time-varying delays are investigated. Some less weak
sufficient conditions based on p-norm and ∞-norm are obtained to guarantee the existence, uniqueness of the equilibrium point for the addressed neural networks
without impulsive control by applying homeomorphism theory. And then, by utilizing inequality technique, Lyapunov functional
method and the analysis method, some new and useful criteria of the globally exponential stability with respect to the equilibrium
point under impulsive control we assumed are derived based on p-norm and ∞-norm, respectively. Finally, an example with simulation is given to show the effectiveness of the obtained results. 相似文献
197.
During the past decade, feature extraction and knowledge acquisition based on video analysis have been extensively researched and tested on many applications such as closed-circuit television(CCTV)data analysis, large-scale public event control, and other daily security monitoring and surveillance operations with various degrees of success. However, since the actual video process is a multi-phased one and encompasses extensive theories and techniques ranging from fundamental image processing, computational geometry and graphics, and machine vision, to advanced artificial intelligence, pattern analysis, and even cognitive science, there are still many important problems to resolve before it can be widely applied. Among them, video event identification and detection are two prominent ones. Comparing with the most popular frame-to-frame processing mode of most of today's approaches and systems, this project reorganizes video data as a 3D volume structure that provides the hybrid spatial and temporal information in a unified space. This paper reports an innovative technique to transform original video frames to 3D volume structures denoted by spatial and temporal features. It then highlights the volume array structure in a so-called "pre-suspicion" mechanism for a later process. The focus of this report is the development of an effective and efficient voxel-based segmentation technique suitable to the volumetric nature of video events and ready for deployment in 3D clustering operations. The paper is concluded with a performance evaluation of the devised technique and discussion on the future work for accelerating the pre-processing of the original video data. 相似文献
198.
Burkhard Schafer 《Datenschutz und Datensicherheit - DuD》2010,34(8):535-538
As readers of this journal will of course know, the Zugangserschwerungsgesetz has caused considerable and often very profound
debate in Germany about the limits of legal and technological interference with the freedom of access to information, culminating
in the temporary refusal of the President to sign the law into action. In the UK by contrast, a core aspect of this law, the
technical prevention of access to sites hosting illegal content by ISPs, was introduced through the so called “Cleanfeed system”
as early as 1996, with little or no public debate, and bypassing by and large all parliamentary procedure and scrutiny. This
article has a threefold aim: First, it gives a brief account of the history and implementation of the UK Cleanfeed system1;
second, it explains some of its more unusual aspects by putting them into the historical and constitutional context of policing
in the UK, and third, it highlights those experiences made with the system that are of direct relevance for the German discussion. 相似文献
199.
The flow of a model non-polar liquid through small carbon nanotubes is studied using non-equilibrium molecular dynamics simulation.
We explain how a membrane of small-diameter nanotubes can transport this liquid faster than a membrane consisting of larger-diameter
nanotubes. This effect is shown to be back-pressure dependent, and the reasons for this are explored. The flow through the
very smallest nanotubes is shown to depend strongly on the depth of the potential inside, suggesting atomic separation can
be based on carbon interaction strength as well as physical size. Finally, we demonstrate how increasing the back-pressure
can counter-intuitively result in lower exit velocities from a nanotube. Such studies are crucial for optimisation of nanotube
membranes. 相似文献
200.