Nokia Research Center (NRC) has been leading Esprit project ARES (Architectural Reasoning for Embedded Systems) for two years. One of the main purposes of ARES is to demonstrate the use of architectural modeling in co...
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Nokia Research Center (NRC) has been leading Esprit project ARES (Architectural Reasoning for Embedded Systems) for two years. One of the main purposes of ARES is to demonstrate the use of architectural modeling in controlling properties of industrial scale products and product families. Two examples are documented. Forward architecting was applied in modeling the new architecture for our mobile phone family showing how to control the dynamic properties of the software. Reverse architecting was used to tune the performance of our telephone switch software. Both cases show that special purpose models can be constructed even for very large systems and they do give valuable insight to the properties of the software.
Since the emergence of object technology, organizations have accumulated a tremendous amount of object-oriented (OO) code. Instead of continuing to recreate components that are similar to existing artifacts, and consi...
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Since the emergence of object technology, organizations have accumulated a tremendous amount of object-oriented (OO) code. Instead of continuing to recreate components that are similar to existing artifacts, and considering the rising costs of development, many organizations would like to decrease software development costs and cycle time by reusing existing OO components. this paper proposes an experiment to verify three hypotheses about the impact of three internal characteristics (inheritance, coupling and complexity) of OO applications on reusability. this verification is done through a machine learning approach (the C4.5 algorithm and a windowing technique). Two kinds of results are produced: (1) for each hypothesis (characteristic), a predictive model is built using a set of metrics derived from this characteristic; and (2) for each predictive model, we measure its completeness, correctness and global accuracy.
We present the results of an empirical study in which we have investigated machine learning (ML) algorithms with regard to their capabilities to accurately assess the correctability of faulty software components. thre...
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We present the results of an empirical study in which we have investigated machine learning (ML) algorithms with regard to their capabilities to accurately assess the correctability of faulty software components. three different families of algorithms have been analyzed. We have used (1) fault data collected on corrective maintenance activities for the Generalized Support software reuse asset library located at the Flight Dynamics Division of NASA's GSFC and (2) product measures extracted directly from the faulty components of this library.
One method of overcoming wire delay due to long resistive interconnect is to insert repeaters in the line. Analytical expressions describing a CMOS inverter driving an RC load have been integrated into a global optimi...
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One method of overcoming wire delay due to long resistive interconnect is to insert repeaters in the line. Analytical expressions describing a CMOS inverter driving an RC load have been integrated into a global optimization algorithm for inserting repeaters into RC trees. the timing model predicts results generally within 10% of SPICE. the global optimization method exhibits total delay improvements of up to 86% over typical cascaded buffer insertion methods. the repeater timing model, global insertion methodology and algorithm, and software implementation are summarized in this paper.
Computer model prediction of motions developed by functional electrical stimulation (FES) can be effective for clinical applications. the musculoskeletal model that responds to electrical stimulation is necessary for ...
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Computer model prediction of motions developed by functional electrical stimulation (FES) can be effective for clinical applications. the musculoskeletal model that responds to electrical stimulation is necessary for the model prediction. In this paper, a musculoskeletal model of the elbow joint was tested experimentally on a normal subject with surface electrode stimulation. In the musculoskeletal model, the musculotendon guide that reflects geometrical arrangement of muscles was adopted. Parameters in the muscle model were adapted to the subject based on the force measured under the isometric condition. the output of the tuned model agreed well with experimental results of the single muscle stimulation at high amplitude of stimulation and results of the simultaneous antagonistic stimulation in some stimulus conditions.
the beat-to-beat regulation of heart rate (HR) is achieved through a beautifully elaborate but not well-understood system of dynamic interactions between sympathetic and parasympathetic (vagal) components of the auton...
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the beat-to-beat regulation of heart rate (HR) is achieved through a beautifully elaborate but not well-understood system of dynamic interactions between sympathetic and parasympathetic (vagal) components of the autonomic nervous system. While numerous investigators consistently have reported dramatic nonlinearities in the HR response to concurrent activation of sympathetic and vagal nerves, a quantitative characterization of such dynamic nonlinearities has been lacking. therefore, in the present study performed in 8 anesthetized Japanese white rabbits, we surgically isolated vagal and cardiac sympathetic efferent nerves such that we were able to stimulate them simultaneously according to mutually independent, band-limited Gaussian white-noise stimuli as we measured the HR response. Under two-input, single-output system assumptions we took advantage of LYSIS 6.2 software to compute first- and second-order nonlinear self kernels relating input nerve stimulation to HR response, as well as compute the nonlinear cross-kernel that quantified the dynamic interaction between concurrent sympathetic and vagal stimulation on HR response. Our results demonstrated nonlinear kernels that significantly enhanced the predictive validity of our model to predict HR response over results obtained using linear kernels alone. We conclude that dynamic nonlinearities play a quantitatively significant role in mediating the HR response to autonomic activation.
In this paper we characterize and model the cost of rework in a Component Factory (CF) organization. A CF is responsible for developing and packaging reusable software components. Data was collected on corrective main...
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ISBN:
(纸本)0897919149
In this paper we characterize and model the cost of rework in a Component Factory (CF) organization. A CF is responsible for developing and packaging reusable software components. Data was collected on corrective maintenance activities for the Generalized Support software reuse asset library located at the Flight Dynamics Division of NASA's GSFC. We then constructed a predictive model of the cost of rework using the C4.5 system for generating a logical classification model. the predictor variables for the model are measures of internal software product attributes. the model demonstrates good prediction accuracy, and can be used by managers to allocate resources for corrective used by managers to allocate resources for corrective maintenance activities. Furthermore, we used the model to generate proscriptive coding guidelines to improve programming practices so that the cost of rework can be reduced in the future. the general approach we have used is applicable to other environments.
Two important phases in the software development process of large systems are modeling and coding of the system components and their interrelations. While the modeling phase is the creative part and must be done manua...
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OO-Method is an OO Methodology that blends the use of formal specification systems with conventional OO methodologies based on practice. In contrast to other approaches in this field ([Jun95,Esd93]), a set of graphica...
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ISBN:
(纸本)3540631070
OO-Method is an OO Methodology that blends the use of formal specification systems with conventional OO methodologies based on practice. In contrast to other approaches in this field ([Jun95,Esd93]), a set of graphical models provided by the methodology allows analysts to introduce the relevant system information to obtain the conceptual model through a requirements collection phase, so that an OO formal specification in Oasis ([Pas92, Pas95-1]), can be generated at any time. this formal specification acts as a high-level system repository. Furthermore, a software prototype which is functionally equivalent to the Oasis specification is also generated in an automated way. this is achieved by defining an execution model which gives the pattern for obtaining a concrete implementation in a declarative or an imperative software development environment (depending on the user choice). the methodology is supported by a CASE workbench.
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