Long-Term Business Modelling Using System Dynamics

This paper presents an overview of the methodology used to model the resource allocation decisions of a research organisation using system dynamics. The resulting model combined the concept of aging chains and co-flows of System Dynamics with conventional spreadsheet analysis, and included representations of staff development and turnover; patent development and licensing revenue; and revenue from other sources. Using the model, senior management were able to evaluate the impact over the coming years of different resource allocation strategies.     

Year 2000 — a Sytems Integration challenge

BT, along with virtually every other IT-dependent business worldwide, is tackling a problem which is quite unique and if not corrected could be disastrous. The problem, sometimes known as the Year 2000 bug or millennium time bomb, has been caused by the use of two digits to represent the year in the majority of our systems and applications. The problem is technically not difficult to fix but the volume of changes occurring, and the need to potentially test every system to ensure that it is year 2000 proof, presents unique and challenging difficulties for integration and testing. Why this is the case, what problems need to be addressed, and an overview of some of the proposed integration and test strategies to tackle these problems, is the subject of this paper.     

Why ‘Current Mode’ Does Not Guarantee Good Performance

It is often said that there is a fundamental difference between current-mode and voltage-mode circuits. This conjecture is discussed in technical and philosophical terms, and it is shown that there is no such performance difference to be found, and that it is not possible to make a clear divide between voltage mode and current mode.And yet performance differences appear in the literature. It is shown that they come from the different design practices of the current-mode and the voltage-mode research groups. The conclusion of this paper is that the practical knowledge of the current-mode research groups should be re-integrated into main-stream IC design, and that all propaganda of the type current-mode is better than voltage-mode should be stopped immediately.     

Pervasive Home Environments

For decades, technologists have been promising the intelligent house. The vision is usually portrayed as a house filled with technology which will do the dweller's bidding and take all domestic drudgery out of their lives. The truly intelligent house is still some way off, but the emergence of broadband, availability of faster, smaller and ever cheaper computing equipment and a variety of wired and wireless network technologies are enabling technologies that bring this vision closer to reality. These technology trends lead to the concept that computing and other smart devices will become pervasive, fully networked and disappear into the infrastructure of the home. People will carry out their tasks unaware of the complexity of the infrastructure that supports their activities in much the same way as people today use mains electricity.This paper introduces these concepts and discusses the technological challenges to be overcome. We present our vision of the pervasive home environment where inhabitants can focus on tasks rather than the technology: I need to create X and send it to Y rather than I need to use this computer and this application which needs access to service A and resource B. Although this sounds simple, the environment needs to understand who I is, and who or what Y is. Appropriate permissions must be in place and resources allocated, if available. The most appropriate interface for the task and user must be determined.The pervasive, intelligent home will make available new ways to access and share information. It will herald new services, such as care and support of people in the home, entertainment, educational and security services. The final part of the paper discusses the commercial opportunities and challenges which must be met, not least the need for industry to agree on open standards and interfaces.     

The Problem with Disruption

Back in January 1995 Clayton Christensen and Joseph Bower wrote an article, Disruptive Technologies: catching the wave, in the Harvard Business Review, in which they argued: No matter the industry, a corporation consists of business units with finite life spans: the technological and market bases of any business will eventually disappear. Good businesses will often be adept at managing a process of incremental improvement, but this kind of incremental change, what they call sustaining technologies, is not the focus of this paper but rather disruptive technologies, which change the rules and leave established businesses with nowhere to go.     

Detection of Defects Using Fault Model Oriented Test Sequences

This paper analyzes the possibilities and limitations of defect detection using fault model oriented test sequences. The analysis is conducted through the example of a short defect considering the static voltage test technique. Firstly, the problem of defect excitation and effect propagation is studied. It is shown that the effect can be either a defective effect or a defect-free effect depending on the value of unpredictable parameters. The concept of Analog Detectability Interval (ADI) is used to represent the range of the unpredictable parameters creating a defective effect. It is demonstrated that the ADIs are pattern dependent. New concepts (Global ADI, Covered ADI) are then proposed to optimize the defect detection taking into account the unpredictable parameters. Finally, the ability of a fault oriented test sequence to detect defect is discussed. In particular, it is shown that the test sequence generated to target the stuck-at faults can reasonably guarantee short defect detection till a limit given by the Analog Detectability Intervals.     

SMART — improving customer service

The quality and consistency of customer service offered by telecommunications providers is now a key differentiator in the residential market-place. BT has introduced the SMART customer handling system to provide competitive advantage through worldclass levels of customer service. A large-scale, three-tier client/server system, SMART exploits the existing functionality, data and security mechanisms of an established mainframe system and adds ease-of-use, reduced error rates and a focus on service and selling. The development and deployment experiences of the SMART programme provide lessons in the delivery of large-scale distributed systems in a business-critical environment. The key issues of security, performance, resilience and operability are discussed and the solutions implemented for SMART are presented.     

Performance Monitoring for In-life Capacity Management

The key to providing a meaningful management view of the performance of complex systems lies in having a co-ordinated process for data collection, analysis and presentation. TeleMarketing Services, such as the Freefone service, provide a good example. Managers of diverse, remote subsystems receive summarised performance and customer service information, mostly in the form of simple graphs, in exchange for providing reliable data. The aim is to bring together a structured view of all the components, including a red-amber-green status table, for use by senior customer-facing staff. Generally, the analyses focus on capacity, forecast and measurement, covering a flexible range of parameters. Managers then have an early view of service degradation, potential capacity exhaustion, workload imbalance and resource wastage, enabling timely remedial action, fault clearance and system enhancements.     

Network computing

Network computing represents a new computing paradigm in which all information, data and software applications reside on a network and are accessed on demand by users. This approach to computing offers the potential for users to access everything from anywhere, removing the constraints of localised storage of information and applications, and, based on evolving standards, allowing access from a range of information appliances. This paper introduces the basic ideas behind network computing, and examines a range of forms it could take. It describes the current status of commercial network computing approaches, with particular emphasis on the use of the Java language, and examines the associated benefits and technical issues. A prototype BT system, developed using Java client software and CORBA-based middleware, is described.     

Simple Laws for Complex Networks

In this paper, we investigate the effect of using two different connection rules (growth and delayed attachment) on the topological properties of simulated networks. We show that comparable values of global variables (like the slope of the power law distribution of node frequency versus node degree) do not guarantee topological similarity, which can have considerable implications for network resilience to cumulative node failure. We present evidence that the decay of the giant component under stress can be approximated using a simple logistic function, the constants of which being determined by the connection rules. The relevance of these findings to present and future telecommunications networks is discussed, especially in terms of potential improvements to robustness.     

Editorial

Future integrated microsystems will benefit significantlyfrom progress in the VLSI field. Two key elements will boostthe implementation of new micro-integrated architectures: progressin batch-manufactured silicon sensors and the introduction ofnew circuit techniques for designing interface circuits. Thesetwo factors will be essential in favoring the transition fromthe present research driven speculations to customer drivenactivities. This paper discusses the key issues in realizingmicrosensors and the most suitable circuit techniques for interfacingand processing their output signals. A number of examples ofintegrated structures will illustrate present problems and possiblesolutions.     

The Supply Chain

One of the most visible examples of ubiquitous computing poised for implementation can be found in the retail industry. Radio frequency identification (RFID) tags are being billed as the replacement for barcoding, the all-pervasive technology which has underpinned supply chains for the past 35 years. The standards allow for up to thirty trillion, trillion, trillion unique addresses, and the ultimate goal is to create an Internet of things in which everyday physical items are networked together. Concerted research effort over the past five years has developed the technology and reduced cost to a point where deployment is now possible. However, the recent heated debate centred on spy chips has highlighted the fact that one person's ubiquitous computing is another person's Big Brother state.     

SRAM-Based FPGAs: Testing the Embedded RAM Modules

This paper addresses the problem of testing the RAM mode of the LUT/RAM modules of configurable SRAM-based Field Programmable Gate Arrays (FPGAs) using a minimum number of test configurations. A model of architecture for the LUT/RAM module with N inputs and 2N memory cells is proposed taking into account the LUT and RAM modes. Targeting the RAM mode, we demonstrate that a unique test configuration is required for a single module. The problem is shown equivalent to the test of a classical SRAM circuit allowing to use existing algorithms such as the March tests. We also propose a unique test configuration called pseudo shift register for an m × m array of modules. In the proposed configuration, the circuit operates as a shift register and an adapted version of the MATS++ algorithm called shifted MATS++ is described.     

Redundancy Removal during High-Level Synthesis Using Scheduling Don‘t-Cares

Previous work in automata theory has shown how to eliminate sequential redundancy from networks of FSMs by finding sequences of inputs and outputs which are never communicated between components of the network. This paper shows that behavior automata—finite-state machines whose inputs and outputs are incompletely scheduled—exhibit similar properties. Using the behavior FSM (BFSM) as a model for scheduling, we show how to identify and eliminate both input and output scheduling dont-cares. When a scheduling dont-care is eliminated from a network of BFSMs, the register-transfer implementation is guaranteed not to suffer from the corresponding dont-care sequence. A definition of scheduling dont-cares improves our understanding of the foundations of high-level synthesis and the relationship between high-level and sequential optimization. In practice, scheduling dont-care elimination is a powerful tool for eliminating redundancy early in the design process.     

Gaussian radial basis functions and inner product spaces

An approximation result is given concerning Gaussian radial basis functions in a general inner product space. Applications are described concerning the classification of the elements of disjoint sets of signals, and also the approximation of continuous real functions defined on all of ⁿ using radial basis function (RBF) networks. More specifically, it is shown that an important large class of classification problems involving signals can be solved using a structure consisting of only a generalized RBF network followed by a quantizer. It is also shown that Gaussian radial basis functions defined on ⁿ can uniformly approximate arbitrarily well over all of ⁿ any continuous real functionalf on ⁿ that meets the condition that |f(x)|0 as x.     

Unified IP Networks

Corporations are looking to harness the flexibility and ubiquity of IP as a means of automating key business transactions and increasing efficiency. As part of this eRevolution corporate businesses are looking at migrating new applications on to their existing IP infrastructures.Computer/telephony integration and unified messaging are applications that will drive forward the integration of voice and data networks for BT's corporate customers, enabling the use of a flexible, shared IP infrastructure for voice and data.While voice over IP is widely seen as the obvious way forward there are many issues to be resolved before this can deliver the anticipated benefits. This paper provides an insight into the building blocks required to enable the development/deployment of shared infrastructure, for quality of service (QoS) capable, unified, IP network solutions. It highlights the detailed understanding and careful design approach required (particularly in the complex area of network QoS) to engineer custom voice solutions as part of a unified IP network design based on today's technology. Emerging protocols and technology, which may turn the unified network dream into reaility, are identified.     

BT Middleware — software as infrastructure

BT Middleware has been in production use since 1987. Every working day a user population of 60 000 people execute 25 million transactions on systems that generate in excess of 70% of BTs revenues. BT Middleware is installed on 32 production mainframe instances.BT Middleware provides both a development and run-time environment for applications that is controlled and manageable. Application standards can be enforced providing reuse of common code as well as common look and feel user interfaces. The use of BT Middleware has allowed the rapid implementation of leading edge solutions to pressing business requirements and Middleware is evolving to allow BTs operational support systems (OSS) to participate seamlessly in complex distributed architectures.The future for BTs OSS lies in their ability to integrate with new applications developed on open systems platforms. BT Middleware has been evolving to provide the required interconnection capabilities and now supports numerous batch and on-line interfaces via strategic infrastructure products. This paper describes the major Middleware infrastructure components developed and supported by BTs London Software Engineering Centre that allow the companys huge investment in OSS to be exploited in todays environment.     

A Single Clocked Adiabatic Static Logic—A Proposal for Digital Low Power Applications

A modified method to construct adiabatic logic is introduced. Advantages of this circuitry over most of the previous ones is that logic behaves in a static mode. In the present research the applicability of a one-phase power clock was studied. The functionality was guaranteed by having the power source frequency much higher than the logic frequency. The new logic gates do not differ much from any standard CMOS logic gates. The only difference is the use of diodes to form logical 1 and 0 states. The static nature of the introduced logic family makes possible to apply the charge recycling technic to other more complex digital circuits and systems. In measurements 77% power saving was achieved compared to a conventional CMOS logic.     

Fully Complex Multi-Layer Perceptron Network for Nonlinear Signal Processing

Designing a neural network (NN) to process complex-valued signals is a challenging task since a complex nonlinear activation function (AF) cannot be both analytic and bounded everywhere in the complex plane . To avoid this difficulty, splitting, i.e., using a pair of real sigmoidal functions for the real and imaginary components has been the traditional approach. However, this ad hoc compromise to avoid the unbounded nature of nonlinear complex functions results in a nowhere analytic AF that performs the error back-propagation (BP) using the split derivatives of the real and imaginary components instead of relying on well-defined fully complex derivatives. In this paper, a fully complex multi-layer perceptron (MLP) structure that yields a simplified complex-valued back-propagation (BP) algorithm is presented. The simplified BP verifies that the fully complex BP weight update formula is the complex conjugate form of real BP formula and the split complex BP is a special case of the fully complex BP. This generalization is possible by employing elementary transcendental functions (ETFs) that are almost everywhere (a.e.) bounded and analytic in . The properties of fully complex MLP are investigated and the advantage of ETFs over split complex AF is shown in numerical examples where nonlinear magnitude and phase distortions of non-constant modulus modulated signals are successfully restored.     

Bibliography on Nullors and Their Applications in Circuit Analysis, Synthesis and Design

A bibliography on research work related to nullors and their applications in circuit analysis, synthesis and design, covering the period 1961–2000, is given.