The preservation of digital artifacts represents an unanswered challenge for the modern information society: XML and its query languages provide an effective environment to address this challenge because of their abil...
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ISBN:
(纸本)1595935258
The preservation of digital artifacts represents an unanswered challenge for the modern information society: XML and its query languages provide an effective environment to address this challenge because of their ability to support temporal information and queries, and make it easy to publish database history to the Web. In this paper, we focus on the problem of preserving, publishing, and querying efficiently the history of a relational database. Past research on temporal databases revealed the difficulty of achieving satisfactory solutions using flat relational tables and SQL. Here we show that the problem can be solved using (a) XML to support temporally grouped representations of the database history, and (b) XQuery to express powerful temporal queries on such representations. Furthermore, the approach is quite general and it can be used to preserve and query the history of multi-version XML documents. Then we turn to the problem of efficient implementation, and we investigate alternative approaches, including (i) XML DBMS, (ii) shredding XML into relational tables and using SQL/XML on these tables, (iii) SQL:2003 nested tables, and iv) OR-DBMS extended with XML support. These experiments suggest that a combination of temporal XML views and physical relational tables provides the best approach for managing temporal database information. Copyright 2006 ACM.
In this paper, we present a topological approach for simplifying continuous functions defined on volumetric domains. We introduce two atomic operations that remove pairs of critical points of the function and design a...
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Decision-making in complex, dynamic, high-risk environments is clearly challenging. Part of this challenge is due to the presence of qualifiers of information, or meta-information (e.g., staleness, uncertainty, source...
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ISBN:
(纸本)094528926X
Decision-making in complex, dynamic, high-risk environments is clearly challenging. Part of this challenge is due to the presence of qualifiers of information, or meta-information (e.g., staleness, uncertainty, source), that alter a person's information processing, situational awareness, and decision-making. We investigated the influence of meta-information on decision-making in a Military Intelligence Operations (10) environment using Cognitive Task Analysis (CTA) techniques. We performed a CTA on IO tasks surrounding the use of smart sensor webs, a relatively new technology that can be used for a variety of IO purposes. Our analysis addressed information management tasks and tactical decision-making tasks using sensor webs. We discovered that a variety of types of meta-information significantly impacted decision-making, and that the influence of meta-information was both context- and task- sensitive. In this paper, we present the results of the CTA and discuss the implications for the development of decision-aiding systems, including the design of constituent displays, interfaces, and automated systems.
In a paper at Fusion 2000, Bjornfot and Svensson discussed the use of HMMs to recognize mobile military organizations moving in column formation along a road from observations of the types and relative positions of it...
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In a paper at Fusion 2000, Bjornfot and Svensson discussed the use of HMMs to recognize mobile military organizations moving in column formation along a road from observations of the types and relative positions of its component vehicles. Straightforward use of standard HMMs in the sequence recognition task restricts the application of this technique to the rather unlikely situation where all vehicle types normally follow each other according to a fixed sequential pattern. In this paper, this restriction is relaxed by representing a multi-level organization by a Hierarchical Hidden Markov Model, in which each possible component sequence for each organizational subunit type is modeled by a separate "sub-HMM". Experiments are carried out using simulated data which illustrate the increased flexibility and applicability of this approach in column recognition tasks.
Decision-making in complex, dynamic, high-risk environments is clearly challenging. Part of this challenge is due to the presence of qualifiers of information, or meta-information (e.g., staleness, uncertainty, source...
Decision-making in complex, dynamic, high-risk environments is clearly challenging. Part of this challenge is due to the presence of qualifiers of information, or meta-information (e.g., staleness, uncertainty, source), that alter a person's information processing, situational awareness, and decision-making. We investigated the influence of meta-information on decision-making in a Military Intelligence Operations (IO) environment using Cognitive Task Analysis (CTA) techniques. We performed a CTA on IO tasks surrounding the use of smart sensor webs, a relatively new technology that can be used for a variety of IO purposes. Our analysis addressed information management tasks and tactical decision-making tasks using sensor webs. We discovered that a variety of types of meta-information significantly impacted decision-making, and that the influence of meta-information was both context- and task- sensitive. In this paper, we present the results of the CTA and discuss the implications for the development of decision-aiding systems, including the design of constituent displays, interfaces, and automated systems.
A numerical model has been developed to analyze and optimize the run-time performance of a disk drive spindle motor. A field-circuit coupled time-stepping finite element method is used for the analysis of the motor op...
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Digital broadcasting is a novel paradigm for the next generation broadcasting. It can offer a new opportunity for interactive services such as content-based browsing, non-linear navigation, usage of user preference, a...
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Software pipelining is an effective technique to reduce cycle count by exploiting instruction level parallelism in loops. It has been implemented in most VLIW DSP compilers. However, software pipelining expands the co...
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