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The Formal Underpinnings of the Response Functions used in XRay Spectral Analysis
, 2001
"... This work provides an indepth mathematical description of the response functions that are used for spatial and spectral analysis of Xray data. The use of such functions is wellknown to anyone familiar with the analysis of Xray data where they may be identied with the quantities contained in t ..."
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Cited by 2 (0 self)
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This work provides an indepth mathematical description of the response functions that are used for spatial and spectral analysis of Xray data. The use of such functions is wellknown to anyone familiar with the analysis of Xray data where they may be identied with the quantities contained in the Ancillary Response File (ARF), the Redistribution Matrix File (RMF), and the Exposure Map. Starting from rstprinciples, explicit mathematical expressions for these functions, for both imaging and dispersive modes, are arrived at in terms of the underlying instrumental characteristics of the telescope including the eects of pointing motion. The response functions are presented in the context of integral equations relating the expected detector count rate to the source spectrum incident upon the telescope. Their application to the analysis of several source distributions is considered. These include multiple, possibly overlapping, and spectrally distinct point sources, as well as extended sources. Assumptions and limitations behind the usage of these functions, as well as their practical computation are addressed.
A formal basis for architectural connection
 ACM TRANSACTIONS ON SOJIWARE ENGINEERING AND METHODOLOGY
, 1997
"... ..."
BULK SIMULATION OF USING INFORMATIONINTENSIVE PRODUCTS AND PRODUCTSERVICE SYSTEMS: FORMAL UNDERPINNINGS
"... In virtual usability testing, simulating the workings of products is typically a computationintensive process. For interactive setups, researchers have put much effort in realizing realtime physics simulations that can keep up with human subjects. But what if fasterthanrealtime simulations woul ..."
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Cited by 1 (1 self)
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physics phenomena offer an excellent opportunity to realize fasterthanrealtime simulations. Building on previous work on noninteractive simulation, this paper gives the concepts and the formal theory of a new approach based on a further simplified reasoning model of humanartifact interaction
AgentSpeak(L): BDI Agents speak out in a logical computable language
, 1996
"... BeliefDesireIntention (BDI) agents have been investigated by many researchers from both a theoretical specification perspective and a practical design perspective. However, there still remains a large gap between theory and practice. The main reason for this has been the complexity of theoremprov ..."
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Cited by 509 (2 self)
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proving or modelchecking in these expressive specification logics. Hence, the implemented BDI systems have tended to use the three major attitudes as data structures, rather than as modal operators. In this paper, we provide an alternative formalization of BDI agents by providing an operational and proof
A classification and comparison framework for software architecture description languages
 IEEE Transactions on Software Engineering
, 2000
"... Software architectures shift the focus of developers from linesofcode to coarsergrained architectural elements and their overall interconnection structure. Architecture description languages (ADLs) have been proposed as modeling notations to support architecturebased development. There is, howev ..."
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Cited by 840 (59 self)
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, however, little consensus in the research community on what is an ADL, what aspects of an architecture should be modeled in an ADL, and which of several possible ADLs is best suited for a particular problem. Furthermore, the distinction is rarely made between ADLs on one hand and formal specification
Social capital, intellectual capital, and the organizational advantage
 Academy of Management Review
, 1998
"... Scholars of the theory of the firm have begun to emphasize the sources and conditions of what has been described a s "the organizational advantage, " rather than focus on the causes and consequences of market failure. Typically, researchers see such organizational advantage a s accruing fr ..."
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Cited by 1100 (1 self)
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in the speed and efficiency in the creation and transfer of knowledge " (1996: 503). This is an important and relatively new perspective on the theory of the firm currently being formalized through the ongoing work of
Foundations for the Study of Software Architecture
 ACM SIGSOFT SOFTWARE ENGINEERING NOTES
, 1992
"... The purpose of this paper is to build the foundation for software architecture. We first develop an intuition for software architecture by appealing to several wellestablished architectural disciplines. On the basis of this intuition, we present a model of software architecture that consists of th ..."
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Cited by 784 (35 self)
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The purpose of this paper is to build the foundation for software architecture. We first develop an intuition for software architecture by appealing to several wellestablished architectural disciplines. On the basis of this intuition, we present a model of software architecture that consists of three components: elements, form, and rationale. Elements are either processing, data, or connecting elements. Form is defined in terms of the properties of, and the relationships among, the elements that is, the constraints on the elements. The rationale provides the underlying basis for the architecture in terms of the system constraints, which most often derive from the system:requirements. We discuss the components of the model in the context of both architectures and architectural styles and present an extended example to illustrate some important architecture and style considerations. We conclude by presenting some of the benefits of our approach to software architecture, summarizing our contributions, and relating our approach to other current work.
A calculus for cryptographic protocols: The spi calculus
 Information and Computation
, 1999
"... We introduce the spi calculus, an extension of the pi calculus designed for the description and analysis of cryptographic protocols. We show how to use the spi calculus, particularly for studying authentication protocols. The pi calculus (without extension) suffices for some abstract protocols; the ..."
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Cited by 919 (55 self)
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We introduce the spi calculus, an extension of the pi calculus designed for the description and analysis of cryptographic protocols. We show how to use the spi calculus, particularly for studying authentication protocols. The pi calculus (without extension) suffices for some abstract protocols; the spi calculus enables us to consider cryptographic issues in more detail. We represent protocols as processes in the spi calculus and state their security properties in terms of coarsegrained notions of protocol equivalence.
Maximum entropy markov models for information extraction and segmentation
, 2000
"... Hidden Markov models (HMMs) are a powerful probabilistic tool for modeling sequential data, and have been applied with success to many textrelated tasks, such as partofspeech tagging, text segmentation and information extraction. In these cases, the observations are usually modeled as multinomial ..."
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Cited by 554 (18 self)
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Hidden Markov models (HMMs) are a powerful probabilistic tool for modeling sequential data, and have been applied with success to many textrelated tasks, such as partofspeech tagging, text segmentation and information extraction. In these cases, the observations are usually modeled as multinomial distributions over a discrete vocabulary, and the HMM parameters are set to maximize the likelihood of the observations. This paper presents a new Markovian sequence model, closely related to HMMs, that allows observations to be represented as arbitrary overlapping features (such as word, capitalization, formatting, partofspeech), and defines the conditional probability of state sequences given observation sequences. It does this by using the maximum entropy framework to fit a set of exponential models that represent the probability of a state given an observation and the previous state. We present positive experimental results on the segmentation of FAQ’s. 1.
Empirical exchange rate models of the Seventies: do they fit out of sample?
 JOURNAL OF INTERNATIONAL ECONOMICS
, 1983
"... This study compares the outofsample forecasting accuracy of various structural and time series exchange rate models. We find that a random walk model performs as well as any estimated model at one to twelve month horizons for the dollar/pound, dollar/mark, dollar/yen and tradeweighted dollar exch ..."
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Cited by 831 (12 self)
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This study compares the outofsample forecasting accuracy of various structural and time series exchange rate models. We find that a random walk model performs as well as any estimated model at one to twelve month horizons for the dollar/pound, dollar/mark, dollar/yen and tradeweighted dollar exchange rates. The candidate structural models include the flexibleprice (FrenkelBilson) and stickyprice (DornbuschFrankel) monetary models, and a stickyprice model which incorporates the current account (HooperMorton). The structural models perform poorly despite the fact that we base their forecasts on actual realized values of future explanatory variables.
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