Structure Identifiability of an NDS with LFT Parametrized Subsystems

Requirements on subsystems have been made clear in this paper for a linear time invariant (LTI) networked dynamic system (NDS), under which subsystem interconnections can be estimated from external output measurements. In this NDS, subsystems may have distinctive dynamics, and subsystem interconnections are arbitrary. It is assumed that system matrices of each subsystem depend on its (pseudo) first principle parameters (FPPs) through a linear fractional transformation (LFT). It has been proven that if in each subsystem, the transfer function matrix (TFM) from its internal inputs to its external outputs is of full normal column rank (FNCR), while the TFM from its external inputs to its internal outputs is of full normal row rank (FNRR), then the NDS is structurally identifiable. Moreover, under some particular situations like there are no direct information transmission from an internal input to an internal output in each subsystem, a necessary and sufficient condition is established for NDS structure identifiability. A matrix valued polynomial (MVP) rank based equivalent condition is further derived, which depends affinely on subsystem (pseudo) FPPs and can be independently verified for each subsystem. From this condition, some necessary conditions are obtained for both subsystem dynamics and its (pseudo) FPPs, using the Kronecker canonical form (KCF) of a matrix pencil.Comment: 16 page

General computational approach for optimal fault detection

We propose a new computational approach to solve the optimal fault detection problem in the most general setting. The proposed procedure is free of any technical assumptions and is applicable to both proper and non-proper systems. This procedure forms the basis of an integrated numerically reliable state-space algorithm, which relies on powerful descriptor systems techniques to solve the underlying computational subproblems. The new algorithm has been implemented into a Fault Detection Toolbox for Matlab

Fund Management and Systemic Risk - Lessons from the Global Financial Crisis

Fund managers play an important role in increasing efficiency and stability in financial markets. But research also indicates that fund management in certain circumstances may contribute to the buildup of systemic risk and severity of financial crises. The global financial crisis provided a number of new experiences on the contribution of fund managers to systemic risk. In this article, we focus on these lessons from the crisis. We distinguish between three sources of systemic risk in the financial system that may arise from fund management: insufficient credit risk transfer to fund managers; runs on funds that cause sudden reductions in funding to banks and other financial entities; and contagion through business ties between fund managers and their sponsors. Our discussion relates to the current intense debate on the role the so-called shadow banking system played in the global financial crisis. Several regulatory initiatives have been launched or suggested to reduce the systemic risk arising from non-bank financial entities, and we briefly discuss the likely impact of these on the sources of systemic risk outlined in the article

Trade Facilitation Needs and Customs Valuation in Fiji

In line with most developing countries, the last decade has seen Fiji adopt an export oriented, outward-looking approach to trade relations. Import restrictions have been largely lifted in favour of export promotion, and as such Fiji now has a more liberalized or open economy with increased volumes of both exports and importsTrade Facilitation, Customs Valuation, Fiji

An exploration of the need for and cost of selected trade facilitation measures in Asia-Pacific in the context of the WTO negotiations

This paper presents the findings and results of an exploratory ARTNeT study on the needs for and costs of implementation of selected trade facilitation measures (TFMs) related to GATT Articles V, VIII and X. This summary paper is based on six ARTNeT working papers issued between January and April 2006, including five country case studies (available at www.artnetontrade.org).WTO, Trade Facilitation,GATT Articles V,VIII and X