Proposed Approach. (proposed + approach)

Distribution by Scientific Domains

Selected Abstracts

Aspect-enhanced goal-driven sequence diagram

Jonathan Lee
Recently, aspect-oriented approaches have resulted in a tremendous impact on the processing of broadly scoped properties during the development of software systems. However, the weaving mechanism of these crosscutting concerns cannot be easily represented with the extant unified modeling language (UML) notation at the early stage of software development life cycle. As an attempt toward the investigation of how the crosscutting behavior takes place, we proposed, in this work, an aspect-enhanced goal-driven approach to modeling the aspectual behavior in UML state transition diagrams and sequence diagrams with the proposed interaction operators based on the aspectual weaving semantics. By introducing the proposed interaction operations in the UML combined fragment, UML sequence diagrams can be further enhanced to support the modeling of the interactions between aspectual and base behavior in the analysis and design stage of software development. To further exemplify our points, the meeting scheduler system is chosen as a vehicle to illustrate the proposed approach. © 2010 Wiley Periodicals, Inc. [source]

A goal-driven approach for service request modeling

Chiung-Hon Leon Lee
We propose a goal-driven approach to model the service request intention in service-oriented systems. The service request intention can be extracted from the user input and modeled by predefined goal models. We identify this problem as the service request intention extraction. If a service-oriented system has the abilities of user's intention extraction and can make some activities to satisfy the extracted intention, the system can provide a more convenient and efficient service for the user. We start the system construction from the view of goal-driven requirements engineering. The requirements specification is generated by the goal-based requirements analysis in which the functional and nonfunctional requirements will be extended with goal models. A set of computable goal models that represent the user requirements is selected and refined as the basis of system services. The designer can also design related system services based on the requirements specification. Based on the proposed intention extraction approach, the user's vague and imprecise intention will be extracted and mapped to computer understandable and computable goal models for representing the intention. A case-based method is developed to implement the intention extraction process. The intention interpretation knowledge is stored in a case base, and the intention interpretation is based on the process of case retrieval and adaptation. A general architecture for an intention-aware service-oriented system is proposed for demonstrating how to apply the proposed approach. © 2010 Wiley Periodicals, Inc. [source]

Evidential reasoning-based nonlinear programming model for MCDA under fuzzy weights and utilities,

Mi Zhou
In a multiple-criteria decision analysis (MCDA) problem, qualitative information with subjective judgments of ambiguity is often provided by people, together with quantitative data that may also be imprecise or incomplete. There are several uncertainties that may be considered in an MCDA problem, such as fuzziness and ambiguity. The evidential reasoning (ER) approach is well suited for dealing with such MCDA problems and can generate comprehensive distributed assessments for different alternatives. Many researches in dealing with imprecise or uncertain belief structures have been conducted on the ER approach. In this paper, both triangular fuzzy weights of criteria and fuzzy utilities assigned to evaluation grades are introduced to the ER approach, which may be incurred in several circumstances such as group decision-making situation. The Hadamard multiplicative combination of judgment matrix is extended for the aggregation of triangular fuzzy judgment matrices, the result of which is applied as the fuzzy weights used in the fuzzy ER approach. The consistency of the aggregated triangular fuzzy judgment matrix is also proved. Several pairs of ER-based programming models are designed to generate the total fuzzy belief degrees and the overall expected fuzzy utilities for the comparison of alternatives. A numerical example is conducted to show the effectiveness of the proposed approach. © 2009 Wiley Periodicals, Inc. [source]

An argument-dependent approach to determining OWA operator weights based on the rule of maximum entropy

Jian Wu
The methods for determining OWA operator weights have aroused wide attention. We first review the main existing methods for determining OWA operator weights. We next introduce the principle of maximum entropy for setting up probability distributions on the basis of partial knowledge and prove that Xu's normal distribution-based method obeys the principle of maximum entropy. Finally, we propose an argument-dependent approach based on normal distribution, which assigns very low weights to these "false" or "biased" opinions and can relieve the influence of the unfair arguments. A numerical example is provided to illustrate the application of the proposed approach. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 209,221, 2007. [source]

University timetabling through conceptual modeling

Jonathan Lee
A number of approaches have been proposed in tackling the timetabling problem, such as operational research, human-machine interaction, constraint programming, expert systems, and neural networks. However, there are still several key challenges to be addressed: easily reformulated to support changes, a generalized framework to handle various timetabling problems, and ability to incorporate knowledge in the timetabling system. In this article, we propose an automatic software engineering approach, called task-based conceptual graphs, to addressing the challenges in the timetabling problem. Task-based conceptual graphs provide the automation of software development processes including specification, verification, and automatic programming. Maintenance can be directly performed on the specifications rather than on the source code; moreover, hard and soft constraints can be easily inserted or removed. A university timetabling system in the Department of Computer Science and Information Engineering at National Central University is used as an illustrative example for the proposed approach. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 1137,1160, 2005. [source]

A fuzzy goal programming procedure for solving quadratic bilevel programming problems

Bijay Baran Pal
This article presents a fuzzy goal programming (FGP) procedure for solving quadratic bilevel programming problems (QBLPP). In the proposed approach, the membership functions for the defined fuzzy objective goals of the decision makers (DM) at both the levels are developed first. Then, a quadratic programming model is formulated by using the notion of distance function minimizing the degree of regret to satisfaction of both DMs. At the first phase of the solution process, the quadratic programming model is transformed into an equivalent nonlinear goal programming (NLGP) model to maximize the membership value of each of the fuzzy objective goals on the extent possible on the basis of their priorities in the decision context. Then, at the second phase, the concept of linear approximation technique in goal programming is introduced for measuring the degree of satisfaction of the DMs at both the levels by arriving at a compromised decision regarding the optimality of two different sets of decision variables controlled separately by each of them. A numerical example is provided to illustrate the proposed approach. © 2003 Wiley Periodicals, Inc. [source]

Underwater SLAM in man-made structured environments

David Ribas
This paper describes a navigation system for autonomous underwater vehicles (AUVs) in partially structured environments, such as dams, harbors, marinas, and marine platforms. A mechanically scanned imaging sonar is used to obtain information about the location of vertical planar structures present in such environments. A robust voting algorithm has been developed to extract line features, together with their uncertainty, from the continuous sonar data flow. The obtained information is incorporated into a feature-based simultaneous localization and mapping (SLAM) algorithm running an extended Kalman filter. Simultaneously, the AUV's position estimate is provided to the feature extraction algorithm to correct the distortions that the vehicle motion produces in the acoustic images. Moreover, a procedure to build and maintain a sequence of local maps and to posteriorly recover the full global map has been adapted for the application presented. Experiments carried out in a marina located in the Costa Brava (Spain) with the Ictineu AUV show the viability of the proposed approach. © 2008 Wiley Periodicals, Inc. [source]

Position and force tracking of a two-manipulator system manipulating a flexible beam

Dong Sun
This article discusses the issue of hybrid position and force control of a two-manipulator system manipulating a flexible beam in trajectory tracking. Unlike our previous approach of set-point position control in the trajectory tracking, the system coordinates are hard to be regulated to the desired states with nonzero tracking velocities under continuous feedback control. In this study, we design a hybrid position and force tracking controller while using saturation control to compensate for the effect of beam vibration dynamics on the tracking performance. All parameters and states used in the controller are readily available so that the proposed method is feasible to implement. Under the proposed controller, the tracking error asymptotically converges to a predetermined boundary. Simulation results demonstrate the validity of the proposed approach. © 2001 John Wiley & Sons, Inc. [source]

Forecasting real-time data allowing for data revisions

Kosei Fukuda
Abstract A modeling approach to real-time forecasting that allows for data revisions is shown. In this approach, an observed time series is decomposed into stochastic trend, data revision, and observation noise in real time. It is assumed that the stochastic trend is defined such that its first difference is specified as an AR model, and that the data revision, obtained only for the latest part of the time series, is also specified as an AR model. The proposed method is applicable to the data set with one vintage. Empirical applications to real-time forecasting of quarterly time series of US real GDP and its eight components are shown to illustrate the usefulness of the proposed approach.,,Copyright © 2007 John Wiley & Sons, Ltd. [source]

A unified model of property integration for batch and continuous processes

AICHE JOURNAL, Issue 7 2010
Cheng-Liang Chen
Abstract This article aims to present a general model for synthesis of property-based resource conservation networks. The proposed model is applicable to batch and continuous processes. Therein, the process systems are characterized by properties instead of composition that is found in most published works to date in the area of resource conservation. By treating continuous process as a special case of batch processes, both kinds of operations can be optimized with a unified model that is developed on the basis of a superstructure. The overall framework of property network is adopted, where material reuse/recycle, interception, and waste treatment are all taken into consideration. Apart from direct reuse/recycle, interception devices are employed to improve stream properties for further recovery, whereas effluent treatment is needed for compliance with environmental discharge limits. In addition, storage vessels are employed in batch processes to override intrinsic time constraint. Four case studies are solved to illustrate the proposed approach. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source]

A bi-criterion optimization approach for the design and planning of hydrogen supply chains for vehicle use

AICHE JOURNAL, Issue 3 2010
Gonzalo Guillén-Gosálbez
Abstract In this article, we address the design of hydrogen supply chains for vehicle use with economic and environmental concerns. Given a set of available technologies to produce, store, and deliver hydrogen, the problem consists of determining the optimal design of the production-distribution network capable of satisfying a predefined hydrogen demand. The design task is formulated as a bi-criterion mixed-integer linear programming (MILP) problem, which simultaneously accounts for the minimization of cost and environmental impact. The environmental impact is measured through the contribution to climate change made by the hydrogen network operation. The emissions considered in the analysis are those associated with the entire life cycle of the process, and are quantified according to the principles of Life Cycle Assessment (LCA). To expedite the search of the Pareto solutions of the problem, we introduce a bi-level algorithm that exploits its specific structure. A case study that addresses the optimal design of the hydrogen infrastructure needed to fulfill the expected hydrogen demand in Great Britain is introduced to illustrate the capabilities of the proposed approach. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source]

Hybrid DEM-compartment modeling approach for granular mixing

AICHE JOURNAL, Issue 1 2007
Patricia M. Portillo
Abstract A new hybrid approach to model powder mixing based on the use of discrete element method (DEM) and compartment modeling is presented. The main motivation behind the proposed approach is to reduce the computational expense of modeling powder mixing by partitioning the mixing system into high shear areas that are modeled using detailed DEM simulations, whereas the remaining process is simulated using stochastic models. The approach can, thus, be used to model complex geometries, as well as a large number of particles that is typically unfeasible with the existing approaches. The results of a horizontal convective mixing vessel are used to illustrate the applicability and efficiency of the proposed approach. © 2006 American Institute of Chemical Engineers AIChE J 2007 [source]

Compact harmonic control network for Doherty power amplifier

Paolo Colantonio
Abstract In this contribution, an innovative design solution to realize small size Doherty power amplifier is presented. The idea consists in the realization of a unique output matching network for both carrier and peaking devices without losing the Doherty behavior. Experimental results performed on uneven Doherty amplifier using GaN HEMT device is given to demonstrate the proposed approach. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 256,258, 2009; Published online in Wiley InterScience ( DOI 10.1002/mop.23983 [source]

Signal enhancement in multiuser communication through adaptivity on transmit

Abdellatif Medouri
Abstract This paper presents a technique to enhance the received signals in a multiuser communication environment through the use of adaptivity on transmit. This technique is based on the principle of reciprocity and is independent of the material medium of transmission and the near-field environments. The objective here is to select a set of weights to be applied to each transmitting antenna, which is a function of the user location. The methodology is not a function of the multipath environment. Furthermore, the transmitted signal may be directed to a particular receiver location and simultaneously be minimized at other receiver locations while operating on the same frequency. Numerical simulations have been made to illustrate the novelty of the proposed approach. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 265,269, 2003; Published online in Wiley InterScience ( DOI 10.1002/mop.11034 [source]