763 resultados para Downside Risk Management


Relevância:

80.00% 80.00%

Publicador:

Resumo:

This paper is from a study on specialist and trade contracting in the construction industry. The research was commissioned by CIRIA and undertaken by the University of Reading in conjunction with Sir Alexander Gibb & Partners Ltd. The purpose of the work was to provide guidance for effective and equitable practice in the management of projects where much of the work is executed, and possibly designed, by specialist and trade contractors (STCs). As part of this study, a preliminary investigation into the nature and origins of specialist contracting was undertaken, in conjunction with a survey of the problems confronting STCs. This paper presents that phase of the project.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Two-dimensional flood inundation modelling is a widely used tool to aid flood risk management. In urban areas, where asset value and population density are greatest, the model spatial resolution required to represent flows through a typical street network (i.e. < 10m) often results in impractical computational cost at the whole city scale. Explicit diffusive storage cell models become very inefficient at such high resolutions, relative to shallow water models, because the stable time step in such schemes scales as a quadratic of resolution. This paper presents the calibration and evaluation of a recently developed new formulation of the LISFLOOD-FP model, where stability is controlled by the Courant–Freidrichs–Levy condition for the shallow water equations, such that, the stable time step instead scales linearly with resolution. The case study used is based on observations during the summer 2007 floods in Tewkesbury, UK. Aerial photography is available for model evaluation on three separate days from the 24th to the 31st of July. The model covered a 3.6 km by 2 km domain and was calibrated using gauge data from high flows during the previous month. The new formulation was benchmarked against the original version of the model at 20 m and 40 m resolutions, demonstrating equally accurate performance given the available validation data but at 67x faster computation time. The July event was then simulated at the 2 m resolution of the available airborne LiDAR DEM. This resulted in a significantly more accurate simulation of the drying dynamics compared to that simulated by the coarse resolution models, although estimates of peak inundation depth were similar.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Airborne scanning laser altimetry (LiDAR) is an important new data source for river flood modelling. LiDAR can give dense and accurate DTMs of floodplains for use as model bathymetry. Spatial resolutions of 0.5m or less are possible, with a height accuracy of 0.15m. LiDAR gives a Digital Surface Model (DSM), so vegetation removal software (e.g. TERRASCAN) must be used to obtain a DTM. An example used to illustrate the current state of the art will be the LiDAR data provided by the EA, which has been processed by their in-house software to convert the raw data to a ground DTM and separate vegetation height map. Their method distinguishes trees from buildings on the basis of object size. EA data products include the DTM with or without buildings removed, a vegetation height map, a DTM with bridges removed, etc. Most vegetation removal software ignores short vegetation less than say 1m high. We have attempted to extend vegetation height measurement to short vegetation using local height texture. Typically most of a floodplain may be covered in such vegetation. The idea is to assign friction coefficients depending on local vegetation height, so that friction is spatially varying. This obviates the need to calibrate a global floodplain friction coefficient. It’s not clear at present if the method is useful, but it’s worth testing further. The LiDAR DTM is usually determined by looking for local minima in the raw data, then interpolating between these to form a space-filling height surface. This is a low pass filtering operation, in which objects of high spatial frequency such as buildings, river embankments and walls may be incorrectly classed as vegetation. The problem is particularly acute in urban areas. A solution may be to apply pattern recognition techniques to LiDAR height data fused with other data types such as LiDAR intensity or multispectral CASI data. We are attempting to use digital map data (Mastermap structured topography data) to help to distinguish buildings from trees, and roads from areas of short vegetation. The problems involved in doing this will be discussed. A related problem of how best to merge historic river cross-section data with a LiDAR DTM will also be considered. LiDAR data may also be used to help generate a finite element mesh. In rural area we have decomposed a floodplain mesh according to taller vegetation features such as hedges and trees, so that e.g. hedge elements can be assigned higher friction coefficients than those in adjacent fields. We are attempting to extend this approach to urban area, so that the mesh is decomposed in the vicinity of buildings, roads, etc as well as trees and hedges. A dominant points algorithm is used to identify points of high curvature on a building or road, which act as initial nodes in the meshing process. A difficulty is that the resulting mesh may contain a very large number of nodes. However, the mesh generated may be useful to allow a high resolution FE model to act as a benchmark for a more practical lower resolution model. A further problem discussed will be how best to exploit data redundancy due to the high resolution of the LiDAR compared to that of a typical flood model. Problems occur if features have dimensions smaller than the model cell size e.g. for a 5m-wide embankment within a raster grid model with 15m cell size, the maximum height of the embankment locally could be assigned to each cell covering the embankment. But how could a 5m-wide ditch be represented? Again, this redundancy has been exploited to improve wetting/drying algorithms using the sub-grid-scale LiDAR heights within finite elements at the waterline.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The paper examines how European retailers are using private standards for food safety and,quality as risk management and competitive tools and the strategic responses of leading Kenyan and other developing country supplier/exporters to such standards. Despite measures to harmonize a 'single market', the European fresh produce market is very diverse in terms of consumer preferences, structural dynamics and attention to and enforcement of food safety and other standards. Leading Kenyan fresh produce suppliers have re-positioned themselves at the high end, including 'high care', segments of the market - precisely those that are most demanding in terms of quality assurance and food safety systems. An array of factors have influenced this strategic positioning, including relatively high international freight costs, the emergence of more effective competition in mainstream product lines, relatively low labor costs for produce preparation, and strong market relationships with selected retail chains. To succeed in this demanding market segment, the industry has had to invest substantially in improved production and procurement systems, upgraded pack house facilities, and quality assurance/food safety management systems. (C) 2005 Elsevier Ltd. All rights reserved.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The Bahrain International Circuit (BIC) is considered its one of the best international racing car track in terms of technical aspects and architectural quality. Two Formula 1 races have been hosted in the Kingdom of Bahrain, in 2004 and 2005, at BIC. The BIC had recently won the award of the best international racing car circuit. This paper highlights on the elements that contributed to the success of such project starting from the architectural aspects, construction, challenges, tendering process, risk management, the workforce, speed of the construction method, and future prospects for harnessing solar and wind energy for sustainable electrification and production of water for the circuit, i.e. making BIC green and environment-friendly international circuit.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Two-dimensional flood inundation modelling is a widely used tool to aid flood risk management. In urban areas, the model spatial resolution required to represent flows through a typical street network often results in an impractical computational cost at the city scale. This paper presents the calibration and evaluation of a recently developed formulation of the LISFLOOD-FP model, which is more computationally efficient at these resolutions. Aerial photography was available for model evaluation on 3 days from the 24 to the 31 of July. The new formulation was benchmarked against the original version of the model at 20 and 40 m resolutions, demonstrating equally accurate simulation, given the evaluation data but at a 67 times faster computation time. The July event was then simulated at the 2 m resolution of the available airborne LiDAR DEM. This resulted in more accurate simulation of the floodplain drying dynamics compared with the coarse resolution models, although maximum inundation levels were simulated equally well at all resolutions tested.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Multi-factor approaches to analysis of real estate returns have, since the pioneering work of Chan, Hendershott and Sanders (1990), emphasised a macro-variables approach in preference to the latent factor approach that formed the original basis of the arbitrage pricing theory. With increasing use of high frequency data and trading strategies and with a growing emphasis on the risks of extreme events, the macro-variable procedure has some deficiencies. This paper explores a third way, with the use of an alternative to the standard principal components approach – independent components analysis (ICA). ICA seeks higher moment independence and maximises in relation to a chosen risk parameter. We apply an ICA based on kurtosis maximisation to weekly US REIT data using a kurtosis maximising algorithm. The results show that ICA is successful in capturing the kurtosis characteristics of REIT returns, offering possibilities for the development of risk management strategies that are sensitive to extreme events and tail distributions.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Uncertainty affects all aspects of the property market but one area where the impact of uncertainty is particularly significant is within feasibility analyses. Any development is impacted by differences between market conditions at the conception of the project and the market realities at the time of completion. The feasibility study needs to address the possible outcomes based on an understanding of the current market. This requires the appraiser to forecast the most likely outcome relating to the sale price of the completed development, the construction costs and the timing of both. It also requires the appraiser to understand the impact of finance on the project. All these issues are time sensitive and analysis needs to be undertaken to show the impact of time to the viability of the project. The future is uncertain and a full feasibility analysis should be able to model the upside and downside risk pertaining to a range of possible outcomes. Feasibility studies are extensively used in Italy to determine land value but they tend to be single point analysis based upon a single set of “likely” inputs. In this paper we look at the practical impact of uncertainty in variables using a simulation model (Crystal Ball ©) with an actual case study of an urban redevelopment plan for an Italian Municipality. This allows the appraiser to address the issues of uncertainty involved and thus provide the decision maker with a better understanding of the risk of development. This technique is then refined using a “two-dimensional technique” to distinguish between “uncertainty” and “variability” and thus create a more robust model.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

A significant part of bank lending in the UK is secured on commercial property and valuations play an important part in this process. They are an integral part of risk management within the banking sector. It is therefore important that valuations are independent and objective and are used properly to ensure that secured lending is soundly based from the perspective of both lender and borrower. The purpose of this research is to examine objectivity and transparency in the valuation process for bank lending and to identify any influences which may undermine the process. A detailed analysis of 31 valuation negligence cases has been followed by two focus groups of lenders and valuers and also questionnaire surveys of commercial lenders and valuers. Many stakeholders exist, for example lenders, borrowers and brokers, who are able to influence the process in various ways. The strongest evidence of overt influence in the process comes from the method of valuer selection with borrowers and brokers seen to be heavily involved. There is some also some evidence of influence during the draft valuation process. A significant minority of valuers feel that inappropriate pressure is applied by borrowers and brokers yet there is no apparent part of the process that leads to this. The panel system employed by lenders is found to be a significant part of the system and merits further examination. The pressure felt by valuers needs more investigation along with the question of if and how the process could dispel such feelings. This is seen as particularly important in the context of bank regulation.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

There is widespread evidence that the volatility of stock returns displays an asymmetric response to good and bad news. This article considers the impact of asymmetry on time-varying hedges for financial futures. An asymmetric model that allows forecasts of cash and futures return volatility to respond differently to positive and negative return innovations gives superior in-sample hedging performance. However, the simpler symmetric model is not inferior in a hold-out sample. A method for evaluating the models in a modern risk-management framework is presented, highlighting the importance of allowing optimal hedge ratios to be both time-varying and asymmetric.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Value chain studies, including production system and market chain studies, are essential to value chain analysis, which when coupled with disease risk analysis is a powerful tool to identify key constraints and opportunities for disease control based on risk management in a livestock production and marketing system. Several production system and market chain studies have been conducted to support disease control interventions in South East Asia. This practical aid summarizes experiences and lessons learned from the implementation of such value chain studies in South East Asia. Based on these experiences it prioritizes the required data for the respective purpose of a value chain study and recommends data collection as well as data analysis tools. This practical aid is intended as an adjunct to the FAO value chain approach and animal diseases risk management guidelines document. Further practical advice is provided for more effective use of value chain studies in South and South East Asia as part of animal health decision support.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

A significant part of bank lending in the UK is secured on commercial property and valuations play an important part in this process. They are an integral part of risk management within the banking sector. It is therefore important that valuations are independent and objective and are used properly to ensure that secured lending is soundly based from the perspective of both lender and borrower. The purpose of this research is to examine objectivity and transparency in the valuation process for bank lending and to identify any influences which may undermine the process. A detailed analysis of 31 valuation negligence cases has been followed by two focus groups of lenders and valuers and also questionnaire surveys of commercial lenders and valuers. Many stakeholders exist, for example lenders, borrowers and brokers, who are able to influence the process in various ways. The strongest evidence of overt influence in the process comes from the method of valuer selection with borrowers and brokers seen to be heavily involved. There is some also some evidence of influence during the draft valuation process. A significant minority of valuers feel that inappropriate pressure is applied by borrowers and brokers yet there is no apparent part of the process that leads to this. The panel system employed by lenders is found to be a significant part of the system and merits further examination. The pressure felt by valuers needs more investigation along with the question of if and how the process could dispel such feelings. This is seen as particularly important in the context of bank regulation.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This paper proposes hybrid capital securities as a significant part of senior bank executive incentive compensation in light of Basel III, a new global regulatory standard on bank capital adequacy and liquidity agreed by the members of the Basel Committee on Banking Supervision. The committee developed Basel III in a response to the deficiencies in financial regulation brought about by the global financial crisis. Basel III strengthens bank capital requirements and introduces new regulatory requirements on bank liquidity and bank leverage. The hybrid bank capital securities we propose for bank executives’ compensation are preferred shares and subordinated debt that the June 2004 Basel II regulatory framework recognised as other admissible forms of capital. The past two decades have witnessed dramatic increase in performance-related pay in the banking industry. Stakeholders such as shareholders, debtholders and regulators criticise traditional cash and equity-based compensation for encouraging bank executives’ excessive risk taking and short-termism, which has resulted in the failure of risk management in high profile banks during the global financial crisis. Paying compensation in the form of hybrid bank capital securities may align the interests of executives with those of stakeholders and help banks regain their reputation for prudence after years of aggressive risk-taking. Additionally, banks are desperately seeking to raise capital in order to bolster balance sheets damaged by the ongoing credit crisis. Tapping their own senior employees with large incentive compensation packages may be a viable additional source of capital that is politically acceptable in times of large-scale bailouts of the financial sector and economically wise as it aligns the interests of the executives with the need for a stable financial system.