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1.
《Information Systems》1999,24(6):457-473
When an organization embarks on e-commerce it rarely has a chance to re-engineer its existing business applications. However, if these business applications were built using an application framework, then one might hope to reuse many of the existing legacy applications in the new e-commerce context. How much of the original application can be reused, and how much does the original application framework have to evolve in order to support this reuse? This paper describes our experience with evolving our framework for building engineered-product business applications so that these applications can be delivered over the Internet. We discuss the general issues created by migrating applications to e-commerce, and identify architectural concerns for application frameworks that must support e-commerce.  相似文献   

2.
As the computer disappears in the environments surrounding our activities, the objects therein become augmented with sensors, actuators, processors, memories, wireless communication modules and they can receive, store, process and transmit information. In addition to objects, spaces also undergo a change towards becoming smart and eventually Ambient Intelligence (AmI) spaces. In order to model the way everyday activities are carried out within an AmI environment, we introduce the notion of “activity sphere”. In this paper, we are interested in the ontology-based representation of activity spheres from two different perspectives (as creators and as observers), as well as the modeling and control of the dynamic nature of activity spheres.  相似文献   

3.
Technological innovation ushered in the computer era, and, after a few years of tutelage by established disciplines, computer science emerged as an independent discipline. In the subsequent decades computer science developed its special identity, sharing the dual character of engineering and mathematics. This evolution is revisited here based on my personal experience. In my view, the notion of computational model has been the enabler of extraordinary creativity, and at the same time the source of critical ...  相似文献   

4.
The ongoing evolution of storage and network technologies has supported the rapid growth in the field of distributed storage over the past few years, but a widely-felt demand for more and better storage is a significant driving force behind this growth. The demand arises from an apparent de-facto economic and cultural mandate to store and archive as many bits as possible. This trend poses interesting new challenges as storage systems are asked to store not just bits, but also the their semantics; for what use is an image that can't be seen because its format has been forgotten or a program that can no longer be executed because the machine that ran it no longer exists?  相似文献   

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Reflection on the natural/artificial, real/imaginary, subjective/objective dicotomies is increasingly the subject of debate on systems of communication, which make more and more widespread use of expert and/or intelligent advanced technologies. This paper analyses different forms of communication operating in a socio-technical system. The analysis is concerned with changes in creativity and participation of the human being in the decision and production processes within various contexts of social life. It is thus important to verify the possibility of an interpolation between vital world, social system, and information technologies in order to understand a possible interrelation between therational and therelational components in the presentsocio-technical system.  相似文献   

8.
The evolving philosophers problem: dynamic change management   总被引:1,自引:0,他引:1  
A model for dynamic change management which separates structural concerns from component application concerns is presented. This separation of concerns permits the formulation of general structural rules for change at the configuration level without the need to consider application state, and the specification of application component actions without prior knowledge of the actual structural changes which may be introduced. In addition, the changes can be applied in such a way so as to leave the modified system in a consistent state, and cause no disturbance to the unaffected part of the operational system. The model is applied to an example problem, `evolving philosophers'. The principles of this model have been implemented and tested in the Conic environment for distributed systems  相似文献   

9.
ISEB is evolving     
《ITNOW》2006,48(5):21
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10.
A maximum pseudo-likelihood approach has previously been developed for fitting pairwise interaction models to patterns generated by growth-interaction processes that are sampled at fixed time points. This approach is now extended, not only by estimating the parameters of the process through time, but also by employing least squares estimation since likelihood based approaches are much more computationally demanding. First, simple stochastic models are used to demonstrate that least squares methods are as powerful as likelihood-based approaches, as well as being mathematically and computationally simpler. The algorithm generates simulations of the deterministic growth-interaction and stochastic immigration-death process, and through these the parameter estimates are determined. Logistic and linear growth are then combined with (symmetric) disc-interaction and (asymmetric) area-interaction processes, and between them these generate a variety of mark-point spatial structures. A robustness study shows that the procedure works well in that the presence, structure and strength of a growth-interaction process can be determined even when an incorrectly presumed model is employed. Thus, the technique is likely to prove to be very useful in general practical applications where the underlying process generating mechanism is almost certain to be unknown. Finally, the procedure is applied to the analysis of a new Swedish pine forest data set for which tree location and diameter at breast height were recorded in 1985, 1990 and 1996.  相似文献   

11.
In recent years there have been rapid developments in both manufacturing and information technologies and their systems. Advances have occured so rapidly that often the results has been “islands” of automation and information subsystems, such as CAD/CAM, robotics, group technology, and office automation. Some recent developments, however, provide capabilities for integrating these “islands” into systems which both improve manufacturing productivity and produce more meaningful management information. Integrated systems seem imminent. Suggestions that could help ensure a smooth evolution toward these systems are made and some conclusions are drawn.  相似文献   

12.
借助拓扑进化网络描述生物进化的模型,设计出网络拓扑进化算法。算法的拓扑进化结构使其具有可变的种群规模,而进化中产生的新解提高了探测空间的能力。通过在算法中引入组合优化问题解的backbone概念,可以用解的相同部分来直观表示进化网络中单元(解)之间的联系。将连续变量转换成二进制编码后,以相同取值的二进制“位”表示解的相同部分,也可以用该算法求解连续函数优化问题。网络拓扑进化算法不规定解的变异方式,可以结合各种现有的技术,具有广泛的应用性。仿真实验表明算法具有较强的空间搜索能力。  相似文献   

13.
DEMON: mining and monitoring evolving data   总被引:4,自引:0,他引:4  
Data mining algorithms have been the focus of much research. In practice, the input data to a data mining process resides in a large data warehouse whose data is kept up-to-date through periodic or occasional addition and deletion of blocks of data. Most data mining algorithms have either assumed that the input data is static, or have been designed for arbitrary insertions and deletions of data records. We consider a dynamic environment that evolves through systematic addition or deletion of blocks of data. We introduce a new dimension, called the data span dimension, which allows user-defined selections of a temporal subset of the database. Taking this new degree of freedom into account, we describe efficient model maintenance algorithms for frequent item sets and clusters. We then describe a generic algorithm that takes any traditional incremental model maintenance algorithm and transforms it into an algorithm that allows restrictions on the data span dimension. We also develop an algorithm for automatically discovering a specific class of interesting block selection sequences. In a detailed experimental study, we examine the validity and performance of our ideas on synthetic and real datasets  相似文献   

14.
We present an extension module for the Dune system. This module, called dune-subgrid, allows to mark elements of another Dune hierarchical grid. The set of marked elements can then be accessed as a Dune grid in its own right. dune-subgrid is free software and is available for download (External Dune Modules: ). We describe the functionality and use of dune-subgrid, comment on its implementation, and give two example applications. First, we show how dune-subgrid can be used for micro-FE simulations of trabecular bone. Then we present an algorithm that allows to use exact residuals for the adaptive solution of the spatial problems of time-discretized evolution equations.  相似文献   

15.
The Trace transform and its applications   总被引:4,自引:0,他引:4  
The Trace transform proposed, a generalization of the Radon transform, consists of tracing an image with straight lines along which certain functionals of the image function are calculated. Different functionals that can be used may be invariant to different transformations of the image. The paper presents the properties the functionals must have in order to be useful in three different applications of the method: construction of invariant features to rotation, translation and scaling of the image, construction of sensitive features to the parameters of rotation, translation and scaling of the image, and construction of features that may correlate well with a certain phenomenon we wish to monitor  相似文献   

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In Arizona, a window of opportunity exists for using planned infrastructure expenditures to construct intelligent lanes on Interstate Highway 10 between Phoenix and Tucson for deploying intelligent vehicles (IVs). In 1998, the University of Arizona formed the Vehicles with Intelligent Systems for Transport Automation research team, which the ADOT charged with the mission of investigating new and existing technologies and concepts that address those issues. The Arizona state legislature and ADOT funded the VISTA project initially. The paper discusses the vehicle and control system.  相似文献   

18.
Parallel algorithms that use shared resources are notoriously difficult to write and verify, especially when properties such as fairness and efficiency are desired. This paper introduces a new synchronization method called the group lock. This method has some of the advantages of strict synchronization methods such as monitors; algorithms written using group lock are quite clear and easy to verify. At the same time, these algorithms generally make better use of parallelism than those written using stricter synchronization methods. In many cases we can obtain worst case time bounds that are constant or logarithmic in the number of processes, thus also insuring bounded fairness. The paper begins with a discussion of related synchronization methods and an introduction to the group lock. This is followed by some examples of applications in algorithms for a readers/writers problem, parallel stacks and queues, implementation of fetch- and-phi routines, and others. Finally, two implementations of group lock are described. A detailed implementation is given for the paracomputer, an idealized MIMD multiprocessor that supports the fetch-and-add synchronization instruction. An implementation is also outlined for general CREW multiprocessors using only reads and writes to shared memory.  相似文献   

19.
A central aim of robotics research is to design robots that can perform in the real world; a real world that is often highly changeable in nature. An important challenge for researchers is therefore to produce robots that can improve their performance when the environment is stable, and adapt when the environment changes. This paper reports on experiments which show how evolutionary methods can provide lifelong adaptation for robots, and how this evolutionary process was embodied on the robot itself. A unique combination of training and lifelong adaptation are used, and this paper highlights the importance of training to this approach.  相似文献   

20.
In this article we describe a new approach in evolutionary robotics according to which human breeders are involved in the evolutionary process. While traditionally robots are selected to reproduce automatically according to a fitness formula, which is a quantitative and strictly defined measure, human breeders can operate selection based on qualitative criteria, and rewarding behaviors that can slip between the meshes woven by the fitness formula. In authors’ opinion this may bring advantages to the evolutionary robotics methodology, allowing the production of robots that display more, and more multiform, behaviors. In order to illustrate this approach, the software Breedbot was developed in which human breeders can intervene in evolving robots, complementing the automatic evaluation. After describing the software, some results on sample evolutionary processes are reported showing that the joint use of human and artificial selection on an exploration task generates robots with a higher performance and in a shorter time compared with the exclusive action of each breeding method. Future work will explore this hypothesis further. This work was presented in part at the First European Workshop on Artificial Life and Robotics, Vienna, Austria, July 12–13, 2007  相似文献   

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