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101.
This is the first part of a large survey paper in which we analyze recent literature on Formal Concept Analysis (FCA) and some closely related disciplines using FCA. We collected 1072 papers published between 2003 and 2011 mentioning terms related to Formal Concept Analysis in the title, abstract and keywords. We developed a knowledge browsing environment to support our literature analysis process. We use the visualization capabilities of FCA to explore the literature, to discover and conceptually represent the main research topics in the FCA community. In this first part, we zoom in on and give an extensive overview of the papers published between 2003 and 2011 on developing FCA-based methods for knowledge processing. We also give an overview of the literature on FCA extensions such as pattern structures, logical concept analysis, relational concept analysis, power context families, fuzzy FCA, rough FCA, temporal and triadic concept analysis and discuss scalability issues.  相似文献   
102.
TALplanner: A temporal logic based forward chaining planner   总被引:1,自引:0,他引:1  
We present TALplanner, a forward-chaining planner based on the use of domain-dependent search control knowledge represented as formulas in the Temporal Action Logic (TAL). TAL is a narrative based linear metric time logic used for reasoning about action and change in incompletely specified dynamic environments. TAL is used as the formal semantic basis for TALplanner, where a TAL goal narrative with control formulas is input to TALplanner which then generates a TAL narrative that entails the goal and control formulas. The sequential version of TALplanner is presented. The expressivity of plan operators is then extended to deal with an interesting class of resource types. An algorithm for generating concurrent plans, where operators have varying durations and internal state, is also presented. All versions of TALplanner have been implemented. The potential of these techniques is demonstrated by applying TALplanner to a number of standard planning benchmarks in the literature. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
103.
In this paper, we evaluate whether the primary supply temperature in district heating networks can be used to control radiator systems in buildings connected to district heating; with the purpose of increasing the ΔT. The primary supply temperature in district heating systems can mostly be described as a function of outdoor temperature; similarly, the radiator supply temperature in houses, offices and industries can also be described as a function of outdoor temperature. To calibrate the radiator control system to produce an ideally optimal radiator supply temperature that produces a maximized ΔT across the substation, the relationship between the primary supply temperature and outdoor temperature must be known. However, even if the relation is known there is always a deviation between the expected primary supply temperature and the actual temperature of the received distribution media. This deviation makes the radiator control system incapable of controlling the radiator supply temperature to a point that would generate a maximized ΔT.  相似文献   
104.
Single crystal silicon and quartz wafers were seeded with colloidal TPA-silicalite-1 crystals. Hydrothermal treatment of the seeded substrates was used to grow dense MFI films. The preferred orientation of the crystals constituting the films as a function of the amount and size of seeds, film thickness and hydrothermal treatment conditions was investigated. In thin films, most of the crystalline material was found to be oriented with the b-axes close to perpendicular to the substrate surface. In thick films, the a- or c-axes were close to perpendicular to the substrate surface depending on the conditions used for hydrothermal treatment. The seed size and amount was found to affect the rate of change in preferred orientation as a function of film thickness. A film growth mechanism which is able to explain the experimental results is proposed.  相似文献   
105.
In this article a very efficient implementation of a 2D-Lattice Boltzmann kernel using the Compute Unified Device Architecture (CUDA?) interface developed by nVIDIA® is presented. By exploiting the explicit parallelism exposed in the graphics hardware we obtain more than one order in performance gain compared to standard CPUs. A non-trivial example, the flow through a generic porous medium, shows the performance of the implementation.  相似文献   
106.
The performance of segmented and continuous penetrators impacting semi-infinite and spaced armor is studied using both the EPIC-2 and HULL hydrocodes. First the performance of a segmented rod is studied, striking semi-infinite armor, for various parameters such as striking velocity, segment spacing and number of segments. Then an actual penetrator configuration proposed by A. Charters is analyzed and the use of normalized penetration is discussed. Finally three-dimensional simulations are presented for segmented and continuous penetrators impacting oblique spaced armor varying such parameters as striking velocity, segment spacing, number of segments, and target thickness.  相似文献   
107.
Variable Resolution 4-k Meshes: Concepts and Applications   总被引:2,自引:0,他引:2  
  相似文献   
108.
109.
This study investigates video recordings of design reviews in architectural education, focusing on how presentations and discussions of designs are contingent on the specific tools employed. In the analyzed recordings, three different setups are utilized: traditional posters, digital slide-show technologies, and combinations of the two. This range of different setups provides a set of contrasts that make visible the role of technologies in shaping the ways in which the reviews are conducted. The analysis is structured in three themes. First, we examine the sequential organization of digital presentations in relation to the spatial structure of poster-based presentations. Second, the different ways in which shared attention is established in digital, paper-based, and hybrid presentation practices are analyzed. Third, we address part-whole relations—how details in presented materials are put in relation to the overarching project or the presentation as a whole. Taken together, the analyses suggest that the detailed organization of the design review is transformed in subtle yet consequential ways through the introduction of digital slide-show technologies. These transformations are consequential not only locally, for the design review itself, but also for the instructive work that is accomplished through this practice. We conclude by discussing some implications for design, arguing that an increased awareness of how the practice is influenced by the different setups might be key for the proper adaptation of presentation technologies to particular purposes.  相似文献   
110.
An important tool for studying standard finitely presented algebras is the Ufnarovski graph. In this paper we extend the use of the Ufnarovski graph to automaton algebras, introducing the generalized Ufnarovski graph. As an application, we show how this construction can be used to test Noetherianity of automaton algebras.  相似文献   
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