bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of road management systems in China
Authors: Wong W. G. , He G. P. , Luk S. T.
Published: November 2009

Since the introduction of pavement management systems (PMS) in China in 1984, there has been significant progress in research and development of such systems. This paper reviews the development of pavement management systems in China. Three main aspects are presented: the development of China PMS (CPMS) by the China Highway Institute, university-based work on PMS, and integration of facility management systems and integration of PMS with geographical information systems based applications. Significant contributions by researchers at Tongji University on PMS in the past 20 years are also discussed. The paper presents current problems in the full implementation of PMS, and further development in the future in China. Based on the understanding of the application of the Chinese PMS and the efforts of various highways departments, the authors provide some recommendations to help tackle real-world problems. It is estimated that full implementation of PMS in the whole country will take another 5–10 years.
Traffic generated by office and retail developments in Singapore
Authors: Tan Y. W. , Fan H. S. L.
Published: November 2009

This paper presents the development of models to estimate traffic generated by office and retail (shopping centre) developments in Singapore, based on surveys conducted at 27 representative sites. Of particular interest are the effects of the Singapore road pricing scheme and accessibility to public transport on traffic generated by these developments. Two different approaches were used to estimate vehicle trips generated by developments: weighted average rate and regression analysis. The study found that the mean trip rate for office sites located within the area charged under road pricing was lower than the rate for sites situated outside; however, the difference was not statistically significant. The mean trip rate for retail sites within the charged area during the weekday evening hour was significantly lower than the rate outside. For both office and retail developments there were strong linear relationships between traffic generated and floor area (either gross or leasable floor area). The inclusion of the variable ‘distance to the nearest Mass Rapid Transit (MRT) station’ to represent accessibility to MRT services proved to be significant in explaining traffic generated for office developments but not for retail. Trip rates for office and retail developments were found to be considerably lower in Singapore than the UK and US rates.
The Buchanan report: 40 years on
Authors: Hall P.
Published: November 2009

The 1963 Buchanan report made significant contributions to the theory and methodology of planning that are of continuing significance, albeit generally unrecognised. Most important was the concept of absolute environmental standards, basic to Buchanan's entire approach, which led him to fundamental and repeated conflict with the economists’ notion that all standards had an economic price capable of tradeoff. It came to a head in the contemporary criticisms of the Buchanan report by Michael Beesley and Christopher Foster, never resolved in debates at the time, and was repeated in the deliberations of the Roskill Commission on the Third London Airport, when Buchanan's 1971 minority report rejected both the cost-benefit approach of the other commissioners and its conclusion that the new airport should be located at Cublington in the Aylesbury Vale. It continues today in the debates about the environment, where environmentalists take an absolute position and economists a relative one.
Planning for the Leeds Supertram
Authors: Pickup R.
Published: November 2009

This paper sets out to show how the Leeds Supertram scheme was conceived as part of the Leeds Transport Strategy and the various procedures and criteria which are necessary if such a scheme is to be brought to fruition. It highlights the issues which emerged and the approach to gaining powers and funding. It demonstrates the good partnership working between the promoters, West Yorkshire PTE and Leeds City Council, and that the scheme has been robust enough to weather all the changes during the last decade and remain the cornerstone of transport ambitions in Leeds. Unfortunately, given recent press speculation that the Government is placing lower priority on major urban transport schemes, the future of the scheme may still not be secure despite the encouragement given following the publication of the Government's Ten Year Transport Plan in 2000.
Are new rail lines right for Britain?
Authors: Harris N. G.
Published: November 2009

A great deal of investment is currently going into the railway industry across Europe, including into new lines. The British Channel Tunnel Rail Link is under construction, and a number of other high-speed lines in Britain have been discussed. This paper considers whether high-speed lines are the best solution in the British context. It challenges those involved in decision-making to determine more clearly the reasons for such high-speed lines, where capacity increases are often more important than achieving end-to-end journey time reductions. A number of other strategies for railway investment are also discussed, with the paper concluding that (after operational improvements), a targeted investment in bottlenecks in the existing system may be the most cost-effective solution in general. However, this response is made more difficult by the performance regime on Britain's privatised railway.
Strategies for the enhancement of rural railways
Authors: Bugarín M. R. , Novales M. , Orro A.
Published: November 2009

The provision of rural public transport has always been seen as a matter of competing for scarce public resources. The fundamental problem is that the demand for rural transport is low and the population is widely dispersed. Conventional public transportation solutions are not able to meet the demand efficiently. In this respect, railway transport proves to be particularly inefficient. In Spain there are approximately 2500 km of rural railway lines carrying low traffic volumes. These have traditionally been considered to be loss-making lines. Yet, in principle, this idea is incorrect. This paper looks at some of the techniques currently being successfully applied on rural railway lines that enable considerable savings on operational and maintenance costs to be made.
Traffic operations at on-street parking facilities
Authors: Yousif S. , Purnawan
Published: November 2009

This study reports on the findings based on observations from sites with parallel and angle parking layouts. The main parameters under consideration were the manoeuvre time for parking or unparking and the gap acceptance to merge into the traffic stream when leaving a parking stall. The results showed that the design of on-street parking layouts strongly affects drivers' parking and unparking behaviour. Alternative suggestions to the design of parking stalls were made depending on local conditions.
King's Cross underground station, London: geotechnical aspects
Authors: Macklin S. R. , Yeow H. C.
Published: November 2009

The redevelopment of London Underground's King's Cross St Pancras Station in central London is being carried out to increase capacity from the current 55 000 passengers per hour during the morning peak to an anticipated 82 000, following the construction of the adjacent Channel Tunnel Rail Link (CTRL) terminus. The work will be undertaken in two phases: phase I works, currently nearing completion, which comprises a new western ticket hall and upgrade of the existing tube ticket hall; and phase II, which will comprise a new northern ticket hall and tunnelled links between the existing underground stations. This paper reviews the considerable amount of geotechnical work carried out for the project and will focus principally on three key areas: (a) developing an understanding of the potential hazards related to the stratigraphy of the site; (b) the use of advanced numerical methods; and (c) the role of instrumentation and monitoring within the design and risk management process.
M1 East Midlands multi-modal study, England
Authors: Malik N.
Published: November 2009

The M1 East Midlands study was one of the first multi-modal studies commissioned as a direct response to the recommendations of the UK Government's 1998 trunk roads review in England. The immediate genesis of the study was a proposal for the widening of the M1 motorway and a bypass of the A6 at Kegworth, which were placed on hold in the trunk roads review. The remit for the study was to develop a long-term (20-year) transport strategy that addressed the problems in the study area. Within this context, the study aimed to set out a plan of specific intervention to address the most urgent transport problems. A multi-modal package with an estimated cost of £1·8 billion was recommended, including substantial motorway widening and junction improvements, three local bypasses, a doubling of heavy rail services, six new light rail lines as well as a number of new strategic park-and-ride sites. In addition, a number of policy and behavioural change recommendations were made. This paper describes the main transport issues in the study area, the range of options considered and the final study recommendations. Headline results of the appraisal outputs are given as well as the response of the Regional Planning Body and the ministerial announcement on the study's recommendations.
Procedures for the assessment of highway structures
Authors: O'Brien E. J. , Žnidaric A. , Brady K. , González A. , O'Connor A.
Published: November 2009

Bridges, earth-retaining walls and buried structures make up a substantial proportion of the fixed assets of the land-based transportation infrastructure within Europe. Little work has been done on the development of documents covering the assessment of highway structures compared to the design of new structures. This paper describes an approach to assessment developed through working groups 4 and 5 of the European Cooperation in Science and Technology (Cost) Action 345, entitled procedures required for assessing highway structures. This action was supported by the European Commission and involved experts from 16 European countries. The ICE trust fund has supported a study of a road bridge in Vienna to demonstrate the applicability and potential benefits of the approach developed through Cost 345. The approach is similar to that used in the UK in that there are five levels of assessment of increasing complexity and reliability, but there are a number of differences. This paper describes the approach developed through Cost 345 with a view to opening the debate on the need for a code of practice for assessment that facilitates the use of site-specific loading.
Assessing heat-adhesive emulsions for tack coats
Authors: Miró Recasens R. , Martínez A. , Pérez Jiménez F.
Published: November 2009

The use of conventional emulsions for tack coats can cause problems as they frequently stick to the tyres of construction vehicles. Consequently, the bond between the asphalt layers is inadequate. Recently, new types of emulsions have been developed from very low-penetration bitumen that contain no flux. They are known as ‘heat-adhesive’ emulsions and they are resistant to construction vehicles. However, the adhesive ability of these new emulsions has not previously been studied closely, particularly at low temperatures. The purpose of this study is to analyse the effect of different heat-adhesive emulsions and to verify their performance in service in comparison with the response of a conventional emulsion. For this reason a new shear test—the LCB test—has been developed. This test is carried out at different temperatures, both on laboratory specimens and on cores extracted from recently constructed pavements, where the same emulsions and dosages have been used. It is the modified heat-adhesive emulsion that performs best over the selected range of temperatures. The conventional heat-adhesive emulsion, while performing well at medium temperatures, does not achieve the same resistance at the other temperatures as it is more temperature susceptible.
The Hong Kong second parking demand study
Authors: Lau W. W. T. , Poon P. S. T. , Tong C. O. , Wong S. C.
Published: November 2009

This paper describes the background, objectives, surveys, models, findings and recommendations of the Hong Kong second parking demand study. This study aims to give strategic directions to guide the planning and management of parking facilities in Hong Kong. It comprises extensive surveys to determine the parking inventory, parking characteristics and driver behaviour. Demand models were developed to predict the future night-time and daytime parking demand over a planning horizon of 15 years. All types of vehicle, including private cars, taxis, motorcycles, coaches and goods vehicles, were included in the analysis. The recommendations of a previous parking demand study have been reviewed, and new recommendations are given.
Enhancing pavement management systems using GIS
Authors: Parida M. , Aggarwal S. , Jain S. S.
Published: November 2009

Pavement management systems (PMS) are useful tools for highway agencies in quantifying the overall maintenance needs of pavements and presenting the alternative maintenance strategies under budget constraints. The most important aspect of development of a PMS is to collect, manage and analyse the pavement condition data in a considerably detailed format. Since geographical information systems (GIS), with their spatial analysis capabilities, match the geographical nature of the road networks, they are considered to be the most appropriate tools to enhance pavement management operations, with features such as graphical display of pavement condition. An attempt has been made in this paper to enhance the PMS process with GIS for an identified highway network. The PMS is based on internationally recognised Highway Development and Management System (HDM-4). The ‘programme analysis’ application of HDM-4 has been used for data analysis and the graphical presentation of the analysis results has been made using commercially available ArcView GIS software.
Laboratory simulation of train loading and tamping on ballast
Authors: McDowell G. R. , Lim W. L. , Collop A. C. , Armitage R. , Thom N. H.
Published: November 2009

A box test has been developed to simulate the effects of train loading and tamping on the performance of four different ballasts. The ballasts have each been loaded in the box by a simulated segment of sleeper for up to a million cycles of traffic loading, representing early life behaviour. Simulated tamping has also been performed on the ballasts causing rearrangement of grains. Results from the box tests have been found to be repeatable, and give realistic stiffness and settlement characteristics compared with full-scale tests on trackbeds in the UK. The performance of each of the four ballasts has been determined in terms of settlement characteristics, stiffness and degradation, and the results have been found to agree with results from Los Angeles abrasion tests and water absorption values, and also with petrographic analysis, thus demonstrating the usefulness of the box test for estimating the performance of ballast in the field.
The safe management of civil airfield pavements
Authors: Barling J. M. , Fleming P.
Published: November 2009

The personal safety of all who either travel by air or perform some service function on our airfields is the principal concern of professionals from many disciplines. This paper examines the safe management of airfield pavements for civilian use from inception to expiry of service life. Against a background of international agreement and national regulations, the functional requirements of airfield pavements, recognised standards of design, UK maintenance best practice and operational incident reporting protocols are examined. Although the UK's record for safety related to pavement construction and maintenance is good, there have been avoidable mistakes and we cannot afford to be complacent. Initiatives by a major airport operator to ensure both compliance with health and safety legislation in construction and highest standards of operational safety are reported. Winter maintenance to ensure runway safety is also examined, together with ongoing research into the effects of environmentally friendly de-icing agents on pavement materials.
Remote automatic incident detection using inductive loops
Authors: Cherrett T. , Waterson B. , McDonald M.
Published: November 2009

This paper describes the remote automatic incident detection algorithm designed to detect abnormal periods of traffic congestion existing over single inductive loop detectors (typically 2 × 1·5 m). This algorithm identifies those detectors which show a critical increase in average loop-occupancy time per vehicle coinciding with a critical decrease in average time-gap between vehicles according to a set of rules previously defined by the operator. The rules define the maximum and minimum values of loop occupancy and time gap respectively for each detector, which when exceeded for a given duration, trigger a report of a potential traffic flow ‘abnormality’ for that time of day at that particular location on the network. Initial rules are developed by studying the 85th percentile values of loop occupancy returned by the urban traffic control system every 30 s. A real-time trial took place between 07:00 and 19:00 over 167 consecutive days involving 74 detectors situated along two sections of the A33 Bassett Avenue and A35 Winchester Road in Southampton. Over this period, 181 and 334 triggers were recorded on the A33 and A35, respectively. An independent operator log showed that over the same period, 32 incidents were recorded on the A33 and 49 on the A35. The remote automatic incident detection system detected 69% and 92% of the verified incidents on the A33 and A35, respectively; the low detection rate on the A33 being mainly due to five incidents which occurred during off-peak periods causing no congestion and were therefore not detected.
Setting road maintenance standards by multicriteria analysis
Authors: Ortiz-García J. J. , Snaith M. S. , Costello S. B.
Published: November 2009

This paper discusses the evolution of highway maintenance standards determination, from purely engineering judgement through the application of scientific research to the inclusion of economic assessment in the process. It then proceeds to discuss more recent initiatives that have identified the need to include not only engineering and economics in the determination of maintenance standards but also social and political factors, together with environmental aspects where appropriate. Finally, multicriteria analysis (MCA) is suggested as an appropriate decision-making tool capable of taking proper account of the dominant social, political and environmental issues in an all-embracing and logical process. The suitability of four candidate MCA methodologies was studied: the utility theory approach, the goals programming approach, methods based on the outranking concept and the analytic hierarchy process (AHP). The research has concluded that the AHP is the most appropriate to use, at least initially, owing to its operational advantages. An example of its use in the determination of highway maintenance standards is provided.
The role of thermal ratcheting in pavement failures
Authors: Croll J. G. A.
Published: November 2009

Although recognised to be a factor in certain failures of pavements, there is evidence that alternations in solar energy may be contributing to considerably wider classes of pavement distress than is currently acknowledged. Restrained expansion or contraction during alternations in heating and cooling often result in forms of distortion that are not fully recovered at the end of each thermal cycle. Over time a form of thermal ratchet leads to an accumulation of failure that can have serious consequences for pavement integrity. This paper attempts to describe a representative range of these thermal ratchet-induced failures. It aims to provide a classification system for failures according to the dominant material failure or mechanical process responsible for the cyclic accumulation of distress. It is suggested that greater recognition of the thermo-mechanical processes responsible for these various types of pavement failure could have important implications for improving future design and maintenance strategies.
Capacity prediction for traffic circles: applicability of ANN
Authors: Özuysal M. , Çalışkanelli S. P. , Tanyel S. , Baran T.
Published: November 2009

The traffic circle is a common solution which is widely used in urban and rural areas of Turkey. Although, most of the traffic circles are designed to be signal-controlled, some of them are still being used as unsignalised intersections in order to provide higher capacity and better performance particularly in rural areas. Regression analysis and gap acceptance-based models are the most used estimation methods for capacity prediction of unsignalised traffic circles. In this study, an artificial neural network model (ANN) was investigated as a new approach as ANN models have been successfully applied in various other traffic studies. The entry capacity was predicted by using exponential and multiple linear regressions, gap acceptance theory and the feed forward backpropagation algorithm type of ANN. The results were compared with well known models. The ANN model including the geometric parameters was found to be the most reliable estimator with 71·6% of proper predictions when the discrepancy percentages of the predicted versus observed entry flows were examined for the models. The multiple linear regression and gap acceptance models followed the ANN model with proper prediction proportions of 63·3 and 51·6%, respectively. On the other hand, models that included only circulating flow parameters were only found to be acceptable for limited geometric data conditions.
A model for the evaluation of airport service quality
Authors: Chou C.-C.
Published: November 2009

In the past many studies have focused on the evaluation of air transportation service quality but most of these studies evaluated airline service quality and only a small number have attempted to evaluate the service quality at airports. Furthermore, the majority of previous studies applied the Servqual method to evaluate the airline service quality and only a few have attempted the evaluation using the multiple criteria decision-making method. The present study attempted to fill this gap in the current literature by establishing a model for the evaluation of airport service quality. A case study of two major Taiwanese international airports was conducted to demonstrate the effectiveness of the proposed model. Finally, some interesting conclusions and useful suggestions are offered to airports as suggestions of ways to improve their service quality.
New deterioration models for sealed granular pavements
Authors: Martin T. C.
Published: November 2009

This study developed mechanistic–empirical deterministic-based pavement deterioration models for rutting, roughness and the structural deterioration of typical good-quality sealed granular pavements that are not liable to rapid deterioration at a network level. The models were based on long-term observational deterioration data collected from Australian arterial road sites in several states for up to 16 years. These data was combined with extended observational data from simulation experiments, using accelerated load testing, which separately quantified the impact on pavement deterioration of changes to maintenance treatments and changes to axle loads. The models were developed for predicting deterioration of sealed granular pavements during the gradual deterioration phase. The deterioration models are applicable to road networks for strategic life-cycle costing analyses. The roughness deterioration model can be used in the estimation of heavy vehicle road wear as a basis for heavy vehicle road-user charges.
Understanding and modelling drainage of railway ballast
Authors: Rushton K. R. , Ghataora G.
Published: November 2009

Railway track drainage has a significant effect on both the response of a rail to loading and the durability of the ballast and sub-ballast. Although various standards and design methods exist for the surface drainage there is limited information on sub-surface drainage. In particular there is a paucity of analytical or numerical studies of drainage of track foundations. The present study re-evaluates results of a laboratory-based investigation of track drainage. A time-variant numerical model, based on the Dupuit–Forchheimer approximation, was developed to reproduce the experimental results. The model was also used to show the importance of the slope of subgrade and the ballast/sub-ballast permeability ratio in reducing the water retention time in the track support layers. The numerical model has practical applications as it can be used to evaluate groundwater conditions beneath the track for rainfall storm return periods and can thus be used to design track drainage.
Comment on historical ICE paper
Authors: Hall P.
Published: November 2009

Sir James Drake (1907–1989) was the creator of the British motorway system. As Borough Surveyor of Blackpool in 1936, he apparently designed it on a sheet of paper. His 1949 Roads Plan for Lancashire was a blueprint for a regional motorway system which he essentially completed over the next quarter-century. In this paper, read to the ICE in late 1956, he calls for completion of a national motorways plan over 25 years, at an estimated cost of £175 million a year. His map is remarkably close to the system that was actually completed by the 1980s.
Conceptions of the city-region: a critical review
Authors: Davoudi S.
Published: November 2009

Since the 1990s, there has been a remarkable resurgence of the concept of the city-region in both academic and policy communities. In broad terms, the concept articulates the relationships between the city and its environs. While the city-region's rising popularity is recent, its origin is not. Despite its long history, however, the concept of the city-region does not enjoy a common definition, neither in its use as an analytical term nor in its upsurge as a political one. While there are clear linkages between the two, the main focus of this review is on the city-region as an analytical construct. Hence, the paper provides a critical review of the different methodologies that have been employed over the last 50 years for defining and mapping the city-region. This work shows that, despite their variations, they share two common features—an urban-centric view of the city-region and an economically driven approach to its definition. These are further elaborated by focusing on the prevailing conception of the city-region as a functional economic space and the dominant top-down approach to delineate the boundaries of what is known as the functional urban region.
Global flagships, local impacts
Authors: Doucet B.
Published: November 2009

Over the past three decades, the use of site-specific, iconic flagship regeneration projects has become a popular tool for urban development. This is particularly true in former industrial cities that have suffered from both economic decline and poor image. Such projects are intended to act as catalysts for further development, to attract inward investment and help produce a new icon or image for the city and, as such, they are often geared to outside audiences of tourists, investors or potential residents. With their high profile and external audience, they strive to become global spaces. However, because they are built into an existing urban fabric, they have a very strong local impact. This paper reviews the development and evolution of flagship regeneration over the past three decades, particularly with reference to how it contrasts with other forms of urban regeneration. It will also review the major criticisms of flagship projects during this time, paying particular attention to their impact on local residents.
Resilience and the city: the water sector
Authors: Hamilton W. A. H.
Published: November 2009

This paper describes historical measures taken by the water sector to increase resilience. Drawing mainly on UK practice and experience in England and Wales, it includes a brief discussion on the nature of urban resilience and on some of the technical, social, political, institutional and environmental factors involved. The main part of the paper covers the measures used to increase resilience in the sector, including those related to water resources, supply, drainage, flood protection and co-systems. The paper concludes with notes on recent developments in the UK, with particular emphasis on the serious urban flooding incidents in the last eight years and their implications for urban resilience.
Ultra-green construction: reactive magnesia masonry products
Authors: Liska M. , Al-Tabbaa A.
Published: November 2009

As worldwide production of Portland cement (PC) is one of the major contributors to global anthropogenic carbon dioxide emissions, a range of carbon-reduction initiatives are being considered. One recent development, namely reactive magnesia cements, has received significant attention as a promising sustainable alternative to PC. Reactive magnesia cements are blends of PC and reactive magnesia in different proportions depending on the intended application, from high-density concrete to porous masonry units. An extensive investigation into the strength development of reactive magnesia cement masonry units, in which the PC is either partially or completely replaced by reactive magnesia, has been carried out. The results show that when subjected to accelerated carbonation conditions, such units can achieve strengths that far exceed those of corresponding PC blocks – both in laboratory studies and full-scale commercial trials. In order to determine their environmental advantages, quantification of carbon dioxide sequestration during carbonation of these blocks was performed using X-ray diffraction. This paper presents an overview of the strength performance of reactive magnesia cements in masonry blocks and links that to microstructural analyses using X-ray diffraction and scanning electron microscopy. The paper also presents a quantification of the degree of hydration and carbonation within the blocks. The results are compared with corresponding PC and lime systems.
Carbon in waste: strategies for treatment and landfilling
Authors: Huber-Humer M. , Mostbauer P. , Lechner P.
Published: November 2009

The high amount of carbon present in waste can be reused, recycled, sequestered in sinks or released into the environment in different forms according to the diverse waste management strategies applied in different countries. When landfilled under anaerobic conditions, carbon is partly transformed into methane. The methane can be used as an alternative energy source or, when not captured, it is released into the atmosphere contributing to the greenhouse effect. The forthcoming essential turn in global energy supply will change anthropogenic carbon fluxes significantly, producing a marked impact on the biosphere and pedosphere as well as waste management issues. Through systematic manipulation of both carbon sources and sinks in all life domains and areas of operation, attempts should be made to enhance sequestration and slow down carbon release processes. Indeed, integrated waste management schemes and adapted technologies are already capable of providing a major contribution to this task. This paper describes several innovative promising strategies that can help reduce carbon emissions from final disposal during landfill operation and aftercare.
Mechanisms of Enhanced Natural Imbibition With Novel Chemicals
Authors: Zhang Jieyuan , Nguyen Quoc P. , Flaaten Adam K. , Pope Gary A.
Published: November 2009

A large body of literature has reflected an extensive experimental study of natural imbibition driven by local capillary pressures at high interfacial tension (IFT). However, water imbibition induced by emulsification at low IFT is not well understood. Recently, anionic surfactants have been shown to induce imbibition in mixed- and oil-wet carbonates. Sodium carbonate has been used to reduce the surfactant adsorption. However, calcium and other divalent cations can cause precipitation of the alkali unless soft water is used. This is a significant limitation of sodium carbonate. The present research both advances our understanding of the use of chemicals to enhance oil recovery (EOR) from fractured carbonate reservoirs and indicates how the process can be optimized using novel chemicals. This research applies to the improvement of oil recovery from mixed- and oil-wet fractured carbonate reservoirs.

We show how to select and evaluate new chemicals as natural imbibition enhancers in carbonate rocks. A novel experimental method has also been developed to quantify the significance of capillary and emulsification driven imbibition because of the presence of the chemical imbibition enhancers. An in situ imbibition profile was visualized using a computed tomography (CT) X-ray scanning technique. The results show that formation of microemulsion strongly promotes water imbibition. The rate was highest for Winsor Type II microemulsion and lowest for Winsor Type I microemulsion. The alkalis exhibited a striking imbibition enhancement driven mainly by alteration of capillary pressure. The performance of the imbibition enhancers was found to be consistent for different core-plug sizes and boundary conditions. A novel alkali has been tested that shows a high tolerance for hardness and, thus, may be a good alternative to sodium carbonate under some conditions.

The application of low-cost chemicals to EOR from fractured carbonates is an extremely significant development owing to the vast volumes of oil in such reservoirs and the lack of practical alternative methods of recovering such oil.
Field Applications of Capacitance-Resistance Models in Waterfloods
Authors: Sayarpour M. , Kabir C. S. , Lake L. W.
Published: November 2009

Application of fast, simple and yet powerful analytic tools, capacitance-resistance models (CRMs), is demonstrated with four field examples. Most waterfloods lend themselves to this treatment. This spreadsheet-based tool is ideally suited for engineers who manage daily flood performance. We envision CRM application to precede any detailed full-field numerical modeling.

We have selected field case studies in a way to demonstrate CRM capabilities in different settings: a tank representation of a field, its ability to determine connectivity between the producers and injectors, and understanding flood efficiencies for the entire field or a portion of a field.

Significant insights about the flood performance over a short time period can be gained by estimating fractions of injected fluid being directed from an injector to various producers and the time taken for an injection signal to reach a producer. Injector-to-producer connectivity may be inferred directly during the course of error minimization. Because the method circumvents geologic modeling and saturation matching, it lends itself to frequent usage without intervention of expert modelers.
Comparison of Stochastic Sampling Algorithms for Uncertainty Quantification
Authors: Mohamed Linah , Christie Mike , Demyanov Vasily
Published: November 2009

History matching and uncertainty quantification are two important research topics in reservoir simulation currently. In the Bayesian approach, we start with prior information about a reservoir (e.g., from analog outcrop data) and update our reservoir models with observations (e.g., from production data or time-lapse seismic). The goal of this activity is often to generate multiple models that match the history and use the models to quantify uncertainties in predictions of reservoir performance. A critical aspect of generating multiple history-matched models is the sampling algorithm used to generate the models. Algorithms that have been studied include gradient methods, genetic algorithms, and the ensemble Kalman filter (EnKF).

This paper investigates the efficiency of three stochastic sampling algorithms: Hamiltonian Monte Carlo (HMC) algorithm, Particle Swarm Optimization (PSO) algorithm, and the Neighbourhood Algorithm (NA). HMC is a Markov chain Monte Carlo (MCMC) technique that uses Hamiltonian dynamics to achieve larger jumps than are possible with other MCMC techniques. PSO is a swarm intelligence algorithm that uses similar dynamics to HMC to guide the search but incorporates acceleration and damping parameters to provide rapid convergence to possible multiple minima. NA is a sampling technique that uses the properties of Voronoi cells in high dimensions to achieve multiple history-matched models.

The algorithms are compared by generating multiple history- matched reservoir models and comparing the Bayesian credible intervals (p10-p50-p90) produced by each algorithm. We show that all the algorithms are able to find equivalent match qualities for this example but that some algorithms are able to find good fitting models quickly, whereas others are able to find a more diverse set of models in parameter space. The effects of the different sampling of model parameter space are compared in terms of the p10-p50-p90 uncertainty envelopes in forecast oil rate.

These results show that algorithms based on Hamiltonian dynamics and swarm intelligence concepts have the potential to be effective tools in uncertainty quantification in the oil industry.
Combined Underground Gas Storage and Enhanced Oil Recovery in a Fractured Reservoir
Authors: de Kok Joop , Clemens Torsten
Published: November 2009

The Schönkirchen Tief reservoir is located in the Vienna basin. The reservoir contained 19 std m3 oil originally in place. The current recovery factor after 45 years of production is 59%. The field was produced by water injection. The wells, located at the crest of the high relief structure are exhibiting a high water cut. In 2006–07, a comprehensive study was performed to optimize the future development of the field.

The field is made up of different types of dolostones. The lower part of the field consists of fractured dolomite, the upper part of weathered dolomite and dolomite debris. A dual-permeability model was used to simulate the flow in the dolomite and the weathered zone, whereas a single-permeability model was sufficient for the debris.

The main recovery mechanisms for this reservoir are imbibition and water/oil gravity drainage. Laboratory experiments indicated that the dolomite is water-wet to mixed-wet at reservoir conditions of 100°C.

The results of the study show that an economically attractive option for the field development is establishing an underground gas storage (UGS) and using the injected gas to increase the oil recovery. Because of the fact that the current reservoir pressure is below initial pressure, within half a year, approximately 1 billion std m3 can be injected. Only approximately one-third of this gas has to remain as cushion gas during the first cycle. To further increase the amount of gas that can be used for UGS, fluids have to be withdrawn from the reservoir. Drilling horizontal wells close to the original oil/water contact enables injection of an additional 2 billion std m3 gas.

The gas injection leads to gas/oil gravity drainage of the oil and water present in the matrix of the fractured reservoir. The oil is collected by the horizontal wells, resulting in incremental oil recovery of up to 5% of oil originally in place.
Monitoring and Control of Drilling Utilizing Continuously Updated Process Models
Authors: Iversen F. P. , Cayeux E. , Dvergsnes E. W. , Gravdal J. E. , Vefring E. H. , Mykletun B. , Torsvoll A. , Omdal S. , Merlo A.
Published: November 2009

Recent developments in drilling technology, such as increased sensory information, enhanced data processing and transmitting capacity and capability, and developments in computer controlled machinery, together with adaptation of already available process technology and know-how, are opening up new possibilities for drilling operations. Application of these combined technologies, together with advanced computer modeling, enables enhanced monitoring and increased optimization and control of drilling operations. This paper presents such an integrated system for monitoring and control of the drilling process, currently in the test phase.

A key element in the methodology used here is that the models for fluid flow and drilling mechanics are continuously updated in real-time according to the measured data using Kalman filtering techniques. By comparing the calibrated models to real-time data, unwanted occurrences can be detected quickly, and mitigating actions may be taken, either through system control or through manual intervention.

Using the calibrated models, safe limits for the drilling operation are computed and enforced, and procedures are optimized. The modules developed cover tripping and reaming, pump start up, friction tests, stick-slip prevention, bit load optimization and monitoring.

The methodology may be applied to drilling operations where the drilling equipment is computer controlled. Surface and preferably downhole data must be available in real time. Rigorous testing with drilling data from offshore drilling operations has been performed, and several full-scale tests have been run on a test rig. The ability to maintain the drilling operation within critical limits has been demonstrated. The methodology may contribute to increased safety and reduced down time during drilling operations.
Is Macroeconomics Off Track?
Authors: Mulligan Casey B
Published: November 2009

Paul Krugman has made the case that economics, at least in Chicago, is grossly off track, but Casey Mulligan does not see this in his area of research.
Where Is Internet Policy Really Headed?
Authors: Hahn Robert
Published: November 2009

A new academic consensus is emerging that innovation is the key to consumer welfare, and rules governing Internet policy need to be updated to reflect this reality, according to Robert Hahn.
Response to the U.S. Securities and Exchange’s Proposed Rule: Roadmap for the Potential Use of Financial Statements Prepared in Accordance with International Financial Reporting Standards by U.S. Issuers (Release No. 33-8831; 34-56217; IC-27924; File No. S7-20-07)
Authors: Frost Carol Ann , Henry Elaine , Lin Stephen W. ,   Research Committee of the American Accounting Association’s International Accounting Section
Published: November 2009

ABSTRACT: This paper is a response to the U.S. Securities and Exchange Commission’s request for comments on its proposed rule concerning a “Roadmap” for the use of financial statements prepared in accordance with International Financial Reporting Standards (IFRS) by U.S. issuers. The paper addresses only a few of the 70 multipart questions contained in the Roadmap (refer to the Appendix for a list of all 70 questions). We find that while there are widely divergent opinions, little empirical evidence directly bears on the question of whether U.S. issuers should be required or permitted to adopt IFRS. We conclude that further analysis of the costs and benefits of a mandated transition to IFRS should be done. Notwithstanding the need for further analysis, we question whether it is justified to withhold from U.S. issuers the option to use IFRS for financial reports based on industry membership or size, when all non-U.S. issuers have the option to do so. While IFRS might marginally increase the concentration among audit firms, research suggests that concentration of audit services may be driven primarily by the litigious environment in the U.S. This suggests that concentration would be relatively unaffected by a change in accounting standards.
Tax Relief, or Lack Thereof, for the Long-Term Care Costs of the Aging Population in America
Authors: Blanthorne Cynthia , Higgins Mark M.
Published: November 2009

ABSTRACT: As the health and longevity of Americans continue to improve, adult children caring for aging parents—possibly at the same time as raising children of their own—is becoming a national phenomenon. This paper examines current and proposed income tax relief for taxpayers who provide financial support for the long-term care of an adult individual (e.g., parent of taxpayer). Four specific tax relief options are evaluated: dependency exemption, head of household filing status, medical itemized deduction, and dependent care credit. The current tax law is not structured to encompass the unprecedented issue of the long-term care costs of the aging population in the United States. In response, various options are introduced to advance the discussion of tax policy alternatives.
Deleterious Associations of Sitting Time and Television Viewing Time With Cardiometabolic Risk Biomarkers
Authors: Thorp Alicia A. , Healy Genevieve N. , Owen Neville , Salmon Jo , Ball Kylie , Shaw Jonathan E. , Zimmet Paul Z. , Dunstan David W.
Published: November 2009

OBJECTIVE

We examined the associations of sitting time and television (TV) viewing time with continuously measured biomarkers of cardio-metabolic risk in Australian adults.

RESEARCH DESIGN AND METHODS

Waist circumference, BMI, resting blood pressure, triglycerides, HDL cholesterol, fasting and 2-h postload plasma glucose, and fasting insulin were measured in 2,761 women and 2,103 men aged ≥30 years (mean age 54 years) without clinically diagnosed diabetes from the 2004–2005 Australian Diabetes, Obesity and Lifestyle (AusDiab) study. Multivariate linear regression analyses examined associations of self-reported sitting time and TV viewing time (hours per day) with these biomarkers, adjusting for potential confounding variables.

RESULTS

For both women and men, sitting time was detrimentally associated with waist circumference, BMI, systolic blood pressure, fasting triglycerides, HDL cholesterol, 2-h postload plasma glucose, and fasting insulin (all P < 0.05), but not with fasting plasma glucose and diastolic blood pressure (men only). With the exception of HDL cholesterol and systolic blood pressure in women, the associations remained significant after further adjustment for waist circumference. TV viewing time was detrimentally associated with all metabolic measures in women and all except HDL cholesterol and blood pressure in men. Only fasting insulin and glucose (men only) remained deleteriously associated with TV viewing time after adjustment for waist circumference.

CONCLUSIONS

In women and men, sitting time and TV viewing time were deleteriously associated with cardio-metabolic risk biomarkers, with sitting time having more consistent associations in both sexes and being independent of central adiposity. Preventive initiatives aimed at reducing sitting time should focus on both nonleisure and leisure-time domains.
Postprandial Diabetic Glucose Tolerance Is Normalized by Gastric Bypass Feeding as Opposed to Gastric Feeding and Is Associated With Exaggerated GLP-1 Secretion
Authors: Dirksen Carsten , Hansen Dorte L. , Madsbad Sten , Hvolris Lisbeth E. , Naver Lars S. , Holst Jens J. , Worm Dorte
Published: November 2009

OBJECTIVE

To examine after gastric bypass the effect of peroral versus gastroduodenal feeding on glucose metabolism.

RESEARCH DESIGN AND METHODS

A type 2 diabetic patient was examined on 2 consecutive days 5 weeks after gastric bypass. A standard liquid meal was given on the first day into the bypassed gastric remnant and on the second day perorally. Plasma glucose, insulin, C-peptide, glucagon, incretin hormones, peptide YY, and free fatty acids were measured.

RESULTS

Peroral feeding reduced 2-h postprandial plasma glucose (7.8 vs. 11.1 mmol/l) and incremental area under the glucose curve (iAUC) (0.33 vs. 0.49 mmol · l−1 · min−1) compared with gastroduodenal feeding. β-Cell function (iAUCCpeptide/Glu) was more than twofold improved during peroral feeding, and the glucagon-like peptide (GLP)-1 response increased nearly fivefold.

CONCLUSIONS

Improvement in postprandial glucose metabolism after gastric bypass is an immediate and direct consequence of the gastrointestinal rearrangement, associated with exaggerated GLP-1 release and independent of changes in insulin sensitivity, weight loss, and caloric restriction.