4612858
Requirements Engineering for Organisational Modelling
This paper explores a semiotic perspective to information systems engineering, using organisational modelling techniques rooted in organisational semiotics. The components and relationships of large corporations are highly complex, volatile and unstructured. Semiotic modelling techniques are therefore introduced to address these challenges posed by large enterprises. MEASUR, a suite of methods based on organisational semiotics, are used to address the IT and organisational requirements, needed to encapsulate behavioural patterns and to formalise the convoluted relationships. A case study illustrating the applicability of MEASUR is presented, to evaluate a crime reporting system from the Police Information Technology Organisation (PITO) in UK, and to examine its application and significance in the modelling of organisations. We focus on two key fundamental issues. Firstly we investigate the agent behaviour within the organisation. Secondly, we analyse the semantics of the relationships between these patterns of behaviour in building a normative model of a large organisation.
4687357
Enterprise Infrastructure Planning - Modelling and Simulation Using the Problem Articulation Method
Current systems development costs rise almost exponentially as development time increases, underlining the importance of effective project management and enterprise planning. Enterprise infrastructure planning offers an avenue to efficiently improve and shorten design time; and to develop a system of high quality and with considerably lower operating and development costs. The Problem Articulation Method (PAM) is a method for articulating business and technical requirements in an organisation. It is capable of assimilating the internal systems changes in response to the dynamics and uncertainties of the business environment. The requirements and specifications from this analysis constitute as a baseline for managing changes, and provide the mechanism by which the reality of the enterprise and its systems can be aligned with planned enterprise objectives. An illustration of planning and development of a procurement system will be used to demonstrate the enterprise infrastructure requirements using a discrete-event enterprise simulation package “Enterprise Dynamic”. This paper will examine the capability of PAM in the articulation and simulation of complex enterprise requirements.
14057050
Environmental scanning on the Internet
This study investigates the important organizational task of environmental scanning in an Internet context. A theoretical model relating potential causal factors to effectiveness of environmental scanning was formulated based on a synthesis of environmental scanning literature that took into consideration the Internet context. A questionnaire was developed for data collection. Responses from 105 organizations were tested for convergent and discriminant validity before the theoretical model was assessed using PLS analysis. Results showed that smaller organizations tend to scan more frequently on the Internet, both use of external consultants and volatility of competitor sector tend to cause organizations to scan more frequently on the Internet, and both use of external consultants and scanning frequency on the Internet tend to result in effectiveness of environmental scanning. Additional insights on these results were obtained through telephone interviews with 10 respondents.
16229677
Qualitative Decision Theory
We describe a framework for specifying conditional desires "desire α by e degrees if β" and evaluating preference queries "would you prefer σ1 over σ2 given ϕ" under uncertainty. We refine the semantics presented in (Tan & Pearl 1994) to allow conditional desires to be overridden by more specific desires in the database. Within this framework, we also enable consideration of surprising worlds having extreme desirability values and the determination of degrees of preference.
1339663
Adaptive beamforming for binary phase shift keying communication systems
The paper revisits adaptive beamforming assisted receiver for multiple antenna aided multiuser systems that employ binary phase shift keying (BPSK) modulation. The standard minimum mean square error (MMSE) design is based on the criterion of minimising the mean square error (MSE) between the beamformer's desired output and complex-valued beamformer's output. Since the desired output for BPSK systems is real-valued, minimising the MSE between the beamformer's desired output and real-part of the beamformer's output can significantly improve the bit error rate (BER) performance, and we refer to this alternative MMSE design as the real-valued MMSE (RV-MMSE) to contrast to the standard complex-valued MMSE (CV-MMSE) design. The minimum BER (MBER) design however still outperforms the RV-MMSE solution, particularly for overloaded systems where degree of freedom of the antenna array is smaller than the number of BPSK users. Adaptive implementation of this RV-MMSE beamforming design is realised using a least mean square (LMS) type adaptive algorithm, which we refer to as the RV-LMS, in comparison to the standard CV-LMS algorithm. The RV-LMS adaptive beamformer is shown to have a similar computational complexity as the adaptive MBER beamforming implementation known as the least bit error rate (LBER), imposing only half of the computational requirements of the CV-LMS algorithm.