孤南-三合村洼陷含油气系统研究

The development petroleum geology has made people from studying and studying and predicting in statically and respectively the pool-forming conditions of an area such as oil source bed, reservoir, overlying formation, migration, trap and preservation, etc. to regarding these conditions as well as roles of generation, reservation and accumulation as an integrated dynamic evolution development system to do study .Meanwhile apply various simulating means to try to predict from quantitative angle. Undoubtedly, the solution of these questions will accumulate exploration process, cut down exploration cost and obtain remarkable economic and social benefits. This paper which take sedimentology ,structural geology and petroleum geology as guides and take petroleum system theory as nucleus and carry out study thinking of beginning with static factor and integration of point and face as well as regarding dynamic state factor as factor and apply study methods of integration of geology, Lab research and numerical modeling proceed integrated dissect and systematic analysis to GuNan-SanHeCun depression. Also apply methods of integration of sequence stratigraphy, biostratigraphy, petrostratigraphy and seismic data to found the time-contour stratigraphic framework and reveal time-space distribution of depositional system and meantime clarify oil-source bed, reservoir and overlying distribution regular patterns. Also use basin analysis means to study precisely the depositional history, packed sequences and evolution. Meanwhile analyze systematically and totally the fracture sequence and fault quality and fault feature, study the structural form, activity JiCi and time-space juxtaposion as well as roles of fault in migration and accumulation of oil and gas of different rank and different quality fault. Simultaneously, utilize seismic, log, analysis testing data and reservoir geology theory to do systematic study and prediction to GuNan-SanHeCun reservoir, study the reservoir types macroscopic distribution and major controlling factors, reservoir rock, filler and porosity structural features as well as distribution of reservoir physical property in 3D space and do comprehensive study and prediction to major controlling and influential factors of reservoir. Furthermore, develop deepingly organic geochemistry comprehensive study, emphasis on two overlaps of oil source rock (ESI, ES3) organic geochemistry features, including types, maturity and spatial variations of organic matter to predict their source potential .Also apply biological marks to proceed oil-to-source correlation ,thereby establish bases for distribution of petroleum system. This study recover the oil generation history of oil source rocks, evaluate source and hydrocarbon discharge potential ,infer pool-forming stages and point out the accumulation direction as well as discover the forming relations of mature oil-source rock and oil reservoir and develop research to study dynamic features of petroleum system. Meanwhile use systematic view, integrate every feature and role of pool forming and the evolution history and pool-forming history, thereby lead people from static conditions such as oil source bed, reservoir, overlying formation, migration, trap and preservation to dynamically analyzing pool-forming process. Also divide GuNan-SanHeCun depression into two second petroleum system, firstly propose to divide second petroleum system according to fluid tress, structural axis and larger faults of cutting depression, and divide lower part of petroleum system into five secondary systems. Meanwhile establish layer analysis and quantitative prediction model of petroleum model, and do quantitative prediction to secondary petroleum system.

港西地区河流相砂岩油藏剩余油分布研究

The Gangxi oil field has reached a stage of high water production. The reservoir parameters, such as reservoir physical characteristics, pore structure, fluid, have obviously changed. This thesis therefore carries out a study of these parameters that control reservoir characteristics, physical and chemical actions that have taken place within the reservoirs due to fluid injection, subsequent variations of reservoir macroscopic physical features, microscopic pore structures, seepages, and formation fluid properties. This study rebuilds a geologic model for this oil field, establishes a log-interpreting model, proposes a methodology for dealing with large pore channels and remnant oil distribution, and offers a basis for effective excavation of potential oil, recovery planning, and improvement of water-injection techniques. To resolve some concurrent key problems in the process of exploration of the Gangxi area, this thesis carries out a multidisciplinary research into reservoir geology, physical geography, reservoir engineering, and oil-water well testing. Taking sandstone and flow unit as objects, this study establishes a fine geologic model by a quantificational or semi-quantificational approach in order to understand the remnant oil distribution and the reservoir potential, and accordingly proposes a plan for further exploration. By rebuilding a geological model and applying reservoir-engineering methods, such as numerical simulation, this thesis studies the oil-water movement patterns and remnant-oil distribution, and further advances a deployment plan for the necessary adjustments and increase of recoverable reserves. Main achievements of this study are as follows: 1. The Minghazhen Formation in the Gangxi area is featured by medium-sinuosity river deposits, manifesting themselves as a transitional type between typical meandering and braided rivers. The main microfacies are products of main and branch channels, levee, inter-channel overflows and crevasse-splay floodplains. The Guantao Group is dominantly braided river deposit, and microfacies are mainly formed in channel bar, braided channel and overbank. Main lithofacies include conglomerate, sandstone, siltstone and shale, with sandstone facies being the principal type of the reservoir. 2. The reservoir flow unit of the Gangxi area can be divided into three types: Type I is a high-quality heterogeneous seepage unit, mainly distributed in main channel; Type II is a moderate-quality semi-heterogeneous seepage unit, mainly distributed in both main and branch channels, and partly seen within inter-channel overflow microfacies; Type III is a low-quality, relatively strong heterogeneous seepage unit, mainly distributed in inter-channel overflow microfacies and channel flanks. 3. Flow units and sedimentary microfacies have exerted relatively strong controls on the flowing of underground oil-water: (1) injection-production is often effective in the float units of Type I and II, whilst in the same group of injection-production wells, impellent velocity depends on flow unit types and injection-production spacing; (2) The injection-production of Type III flow unit between the injection-production wells of Type I and II flow units, however, are little effective; (3) there can form a seepage shield in composite channels between channels, leading to inefficient injection and production. 4. Mainly types of large-scale remnant-oil distribution are as follows: (1) remnant oil reservoir of Type III flow unit; (2) injection-production well group of remnant oil area of Type III flow unit; (3) remnant oil reservoirs that cannot be controlled by well network, including reservoir featured by injection without production, reservoir characterized by production without injection, and oil reservoir at which no well can arrive; (4) remnant oil area where injection-production system is not complete. 5. Utilizing different methods to deal with different sedimentary types, sub-dividing the columns of up to 900 wells into 76 chronostratigraphic units. Four transitional sandstone types are recognized, and contrast modes of different sandstone facies are summarized Analyzing in details the reservoirs of different quality by deciphering densely spaced well patterns, dividing microscopic facies and flow units, analyzing remnant oil distribution and its effect on injection-production pattern, and the heterogeneity. Theory foundation is therefore provided for further excavation of remnant oil. Re-evaluating well-log data. The understanding of water-flood layers and conductive formations in the Gangxi area have been considerably improved, and the original interpretations of 233 wells have changed by means of double checking. Variations of the reservoirs and the fluid and formation pressures after water injection are analyzed and summarized Studies are carried out of close elements of the reservoirs, fine reservoir types, oil-water distribution patterns, as well as factors controlling oil-gas enrichment. A static geological model and a prediction model of important tracts are established. Remaining recoverable reserves are calculated of all the oil wells and oil-sandstones. It is proposed that injection-production patterns of 348 oil-sandstones should be adjusted according to the analysis of adaptability of all kinds of sandstones in the injection-production wells.

文33块沙二下段油藏动态模型及剩余油预测

By applying synthetically multi-subject theories, methods and technology, such as petroleum geology, sedimentology, seep mechanics, geochemistry, geophysics and so on; and by making full use of computer; combining quantity and quality, macroscopic and microscopic, intensive static and active description, comprehensive studying and physical modeling, 3 dimension and 4 dimension description; the paper took Wen-33 block of Zhongyuan oil field as an example; and studied reservoir macroscopic and microscopic parameter changing rule and evolve mechanics in different water-blood stage. The reservoir dynamic model and remaining-oil distribution mode was established, and several results were achieved as follows: (1) Three types of parameter gaining, optimizing and whole data body of Wen33th reservoir were established. Strata framework, structure framework, reservoir types and distribution of Wen33th reservoir were discussed. Reservoir genesis types, space distribution law and evolve rule of Wen33th reservoir were explained. 4D dynamic model of macroscopic parameter of reservoir flow dynamic geologic function of Wen33th reservoir was established. The macroscopic remaining-oil distribution and control factor was revealed. The models of the microscopic matrix field, pore-throat network field, fluid field, clay mineral field of Wen-33 block were established. The characters, changing rules and controlled factors in different water stage were revealed. The evolve rule and mechanics of petroleum fluid field in Wen-33 block reservoir were revealed. Macroscopic and microscopic remaining oil distribution mode of Wen-33 block were established. Seven types, namely 12 shapes of dynamic model of microscopic remaining oil were discussed, and the distribution of mover remaining oil was predicted. Emulation model: mathematical model and prediction model of Wen-33 block were established. The changing mechanics of reservoir parameter and distribution of remaining-oil were predicted. Firstly, the paper putting forward that the dynamic geologic function of petroleum development is the factor of controlling remaining-oil, which is the main factor leading to matrix field, network field, clay mineral field, fluid field, physic and chemical field, stress field and fluid field forming and evolving. (10) A set of theories, methods and technologies of investigating, describing, characterizing and predicting complex fault-block petroleum were developed.

三峡库区滑坡的时空分布、成因及其预报模式

Landslides are widely distributed along the main stream banks of the Three Gorges Reservoir area. Especially with the acceleration of the human economic activities in the recent 30 years, the occurrence of landslide hazards in the local area trends to be more serious. Because of the special geological, topographic and climatic conditions of the Three Gorges areas, many Paleo-landslides are found along the gentle slope terrain of the population relocation sites. Under the natural condition, the Paleo-landslides usually keep stable. The Paleo-landslides might revive while they are influenced under the strong rainfall, water storage and migration engineering disturbance. Therefore, the prediction and prevention of landslide hazards have become the important problem involving with the safety of migration engineering of the Three Gorges Reservoir area.The past research on the landslides of the Three Gorges area is mainly concentrated on the stability analysis of individual landslide, and importance was little attached to the knowledge on the geological environment background of the formation of regional landslides. So, the relationship between distribution and evolution of landslides and globe dynamic processes was very scarce in the past research. With further study, it becomes difficult to explain the reasons for the magnitude and frequency of major geological hazards in terms of single endogenic or exogenic processes. It is possible to resolve the causes of major landslides in the Three Gorges area through the systematic research of regional tectonics and river evolution history.In present paper, based on the view of coupling of earth's endogenic and exogenic processes, the author researches the temporal and spacial distribution and formation evolution of major landslides(Volume^lOOX 104m3) in the Three Gorges Reservoir area through integration of first-hand sources statistics, .geological evolution history, isotope dating and numerical simulation method etc. And considering the main formation factors of landslides (topography, geology and rainfall condition), the author discusses the occurrence probability and prediction model of rainfall induced landslides.The distribution and magnitude of Paleo-landslides in the Three Gorges area is mainly controlled by lithology, geological structure, bank slope shape and geostress field etc. The major Paleo-landslides are concentrated on the periods 2.7-15.0 X 104aB.R, which conrresponds to the warm and wettest Paleoclimate stages. In the same time, the Three Gorges area experiences with the quickest crust uplift phase since 15.0X 104aB.P. It is indicated that the dynamic factor of polyphase major Paleo-landslides is the coupling processes of neotectonic movement and Quaternary climate changes. Based on the numerical simulation results of the formation evolution of Baota landslide, the quick crust uplift makes the deep river incision and the geostress relief causes the rock body of banks flexible. Under the strong rainfall condition, the pore-water pressure resulted from rain penetration and high flood level can have the shear strength of weak structural plane decrease to a great degree. Therefore, the bank slope is easy to slide at the slope bottom where shear stress concentrates. Finally, it forms the composite draught-traction type landslide of dip stratified rocks.The susceptibility idea for the rainfall induced landslide is put forward in this paper and the degree of susceptibility is graded in terms of the topography and geological conditions of landslides. Base on the integration with geological environment factors and rainfall condition, the author gives a new probabilistic prediction model for rainfall induced landslides. As an example from Chongqing City of the Three Gorges area, selecting the 5 factors of topography, lithology combination, slope shape, rock structure and hydrogeology and 21 kinds of status as prediction variables, the susceptibility zonation is carried out by information methods. The prediction criterion of landslides is established by two factors: the maximum 24 hour rainfall and the antecedent effective precipitation of 15 days. The new prediction model is possible to actualize the real-time regional landslide prediction and improve accuracy of landslide forecast.

Uncertainty in wind energy forecasting

Wind energy is the energy source that contributes most to the renewable energy mix of European countries. While there are good wind resources throughout Europe, the intermittency of the wind represents a major problem for the deployment of wind energy into the electricity networks. To ensure grid security a Transmission System Operator needs today for each kilowatt of wind energy either an equal amount of spinning reserve or a forecasting system that can predict the amount of energy that will be produced from wind over a period of 1 to 48 hours. In the range from 5m/s to 15m/s a wind turbine’s production increases with a power of three. For this reason, a Transmission System Operator requires an accuracy for wind speed forecasts of 1m/s in this wind speed range. Forecasting wind energy with a numerical weather prediction model in this context builds the background of this work. The author’s goal was to present a pragmatic solution to this specific problem in the ”real world”. This work therefore has to be seen in a technical context and hence does not provide nor intends to provide a general overview of the benefits and drawbacks of wind energy as a renewable energy source. In the first part of this work the accuracy requirements of the energy sector for wind speed predictions from numerical weather prediction models are described and analysed. A unique set of numerical experiments has been carried out in collaboration with the Danish Meteorological Institute to investigate the forecast quality of an operational numerical weather prediction model for this purpose. The results of this investigation revealed that the accuracy requirements for wind speed and wind power forecasts from today’s numerical weather prediction models can only be met at certain times. This means that the uncertainty of the forecast quality becomes a parameter that is as important as the wind speed and wind power itself. To quantify the uncertainty of a forecast valid for tomorrow requires an ensemble of forecasts. In the second part of this work such an ensemble of forecasts was designed and verified for its ability to quantify the forecast error. This was accomplished by correlating the measured error and the forecasted uncertainty on area integrated wind speed and wind power in Denmark and Ireland. A correlation of 93% was achieved in these areas. This method cannot solve the accuracy requirements of the energy sector. By knowing the uncertainty of the forecasts, the focus can however be put on the accuracy requirements at times when it is possible to accurately predict the weather. Thus, this result presents a major step forward in making wind energy a compatible energy source in the future.

Real-Time and Data-Driven Operation Optimization and Knowledge Discovery for an Enterprise Information System

An enterprise information system (EIS) is an integrated data-applications platform characterized by diverse, heterogeneous, and distributed data sources. For many enterprises, a number of business processes still depend heavily on static rule-based methods and extensive human expertise. Enterprises are faced with the need for optimizing operation scheduling, improving resource utilization, discovering useful knowledge, and making data-driven decisions.

This thesis research is focused on real-time optimization and knowledge discovery that addresses workflow optimization, resource allocation, as well as data-driven predictions of process-execution times, order fulfillment, and enterprise service-level performance. In contrast to prior work on data analytics techniques for enterprise performance optimization, the emphasis here is on realizing scalable and real-time enterprise intelligence based on a combination of heterogeneous system simulation, combinatorial optimization, machine-learning algorithms, and statistical methods.

On-demand digital-print service is a representative enterprise requiring a powerful EIS.We use real-life data from Reischling Press, Inc. (RPI), a digit-print-service provider (PSP), to evaluate our optimization algorithms.

In order to handle the increase in volume and diversity of demands, we first present a high-performance, scalable, and real-time production scheduling algorithm for production automation based on an incremental genetic algorithm (IGA). The objective of this algorithm is to optimize the order dispatching sequence and balance resource utilization. Compared to prior work, this solution is scalable for a high volume of orders and it provides fast scheduling solutions for orders that require complex fulfillment procedures. Experimental results highlight its potential benefit in reducing production inefficiencies and enhancing the productivity of an enterprise.

We next discuss analysis and prediction of different attributes involved in hierarchical components of an enterprise. We start from a study of the fundamental processes related to real-time prediction. Our process-execution time and process status prediction models integrate statistical methods with machine-learning algorithms. In addition to improved prediction accuracy compared to stand-alone machine-learning algorithms, it also performs a probabilistic estimation of the predicted status. An order generally consists of multiple series and parallel processes. We next introduce an order-fulfillment prediction model that combines advantages of multiple classification models by incorporating flexible decision-integration mechanisms. Experimental results show that adopting due dates recommended by the model can significantly reduce enterprise late-delivery ratio. Finally, we investigate service-level attributes that reflect the overall performance of an enterprise. We analyze and decompose time-series data into different components according to their hierarchical periodic nature, perform correlation analysis,

and develop univariate prediction models for each component as well as multivariate models for correlated components. Predictions for the original time series are aggregated from the predictions of its components. In addition to a significant increase in mid-term prediction accuracy, this distributed modeling strategy also improves short-term time-series prediction accuracy.

In summary, this thesis research has led to a set of characterization, optimization, and prediction tools for an EIS to derive insightful knowledge from data and use them as guidance for production management. It is expected to provide solutions for enterprises to increase reconfigurability, accomplish more automated procedures, and obtain data-driven recommendations or effective decisions.

Development and usability testing of a Web-based decision aid for families of patients receiving prolonged mechanical ventilation.

BACKGROUND: Web-based decision aids are increasingly important in medical research and clinical care. However, few have been studied in an intensive care unit setting. The objectives of this study were to develop a Web-based decision aid for family members of patients receiving prolonged mechanical ventilation and to evaluate its usability and acceptability. METHODS: Using an iterative process involving 48 critical illness survivors, family surrogate decision makers, and intensivists, we developed a Web-based decision aid addressing goals of care preferences for surrogate decision makers of patients with prolonged mechanical ventilation that could be either administered by study staff or completed independently by family members (Development Phase). After piloting the decision aid among 13 surrogate decision makers and seven intensivists, we assessed the decision aid's usability in the Evaluation Phase among a cohort of 30 surrogate decision makers using the Systems Usability Scale (SUS). Acceptability was assessed using measures of satisfaction and preference for electronic Collaborative Decision Support (eCODES) versus the original printed decision aid. RESULTS: The final decision aid, termed 'electronic Collaborative Decision Support', provides a framework for shared decision making, elicits relevant values and preferences, incorporates clinical data to personalize prognostic estimates generated from the ProVent prediction model, generates a printable document summarizing the user's interaction with the decision aid, and can digitally archive each user session. Usability was excellent (mean SUS, 80 ± 10) overall, but lower among those 56 years and older (73 ± 7) versus those who were younger (84 ± 9); p = 0.03. A total of 93% of users reported a preference for electronic versus printed versions. CONCLUSIONS: The Web-based decision aid for ICU surrogate decision makers can facilitate highly individualized information sharing with excellent usability and acceptability. Decision aids that employ an electronic format such as eCODES represent a strategy that could enhance patient-clinician collaboration and decision making quality in intensive care.

Multiphysics modelling of the metals casting process

Metals casting is a process governed by the interaction of a range of physical phenomena. Most computational models of this process address only what are conventionally regarded as the primary phenomena-heat conduction and solidification. However, to predict the formation of porosity (a factor of key importance in cast quality) requires the modelling of the interaction of the fluid flow, heat transfer, solidification and the development of stress-deformation in the solidified part of a component. In this paper, a model of the casting process is described which addresses all the main continuum phenomena involved in a coupled manner. The model is solved numerically using novel finite volume unstructured mesh techniques, and then applied to both the prediction of shape deformation (plus the subsequent formation of a gap at the metal-mould interface and its impact on the heat transfer behaviour) and porosity formation in solidifying metal components. Although the porosity prediction model is phenomenologically simplistic it is based on the interaction of the continuum phenomena and yields good comparisons with available experimental results. This work represents the first of the next generation of casting simulation tools to predict aspects of the structure of cast components.

Explicit finite volume modeling of aircraft anti-icing and de-icing

In this paper, a runback water and ice prediction model is extended to anti-icing and thermal de-icing situations. The resulting coupled equations that govern thin-film flow, ice accretion, and heat conduction in the multilayered system substrate-ice-water are solved using an explicit finite volume approach. The procedure is implemented in the three-dimensional icing code ICECREMO2, and both structured and unstructured grids can be considered. Numerical results are presented to compare the present code simulations to some data provided by other ice prediction codes and to show the capabilities of the present numerical tool.

Complement Component 3: an assessment of association with AMD and analysis of gene-gene and gene-environment interactions in a Northern Irish cohort

Purpose: A non-synonymous single nucleotide polymorphism ( SNP) in complement component 3 has been shown to increase the risk of age-related macular degeneration (AMD). We assess its effect on AMD risk in a Northern Irish sample, test for gene-gene and gene-environment interaction, and review a risk prediction model.

High-pressure volumetric properties of imidazolium-based ionic liquids: Effect of the anion

The densities of five imidazolium-based ionic liquids (ILs) (1-butyl-3-methylimidazolium tetrafluoroborate, [CiC4-Im][BF 4]; 1-butyl-3-methylimidazolium hexafluorophosphate, [CiC 4Im][PF6]; 1-butyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}imide, [C1C4Im][Tf 2N]; 1-ethyl-3-methylimidazoliumbis{(trifluoromethyl)sulfonyl}-imide, [C1C2Im][Tf2N]; l-ethyl-3-methylimidazolium ethylsulfate, [C1C2Im][EtSO4]) were measured as a function of temperature from (293 to 415) K and over an extended pressure range from (0.1 to 40) MPa using a vibratingtube densimeter. Knowledge of the variation of the density with temperature and pressure allows access to the mechanical coefficients: thermal expansion coefficient and isothermal compressibility. The effects of the anion and of the length of the alkyl chain on the imidazolium ring on the volumetric properties were particularly examined. The mechanical coefficients were compared with those of common organic solvents, water and liquid NaCl. Finally, a prediction model, based on an "ideal" volumetric behavior of the ILs, is proposed to allow calculation of the molar volume of imidazolium-based ionic liquids as a function of temperature. ©2007 American Chemical Society.

Surveillance for ocular hypertension: An evidence synthesis and economic evaluation

OBJECTIVES: To determine effective and efficient monitoring criteria for ocular hypertension [raised intraocular pressure (IOP)] through (i) identification and validation of glaucoma risk prediction models; and (ii) development of models to determine optimal surveillance pathways.

DESIGN: A discrete event simulation economic modelling evaluation. Data from systematic reviews of risk prediction models and agreement between tonometers, secondary analyses of existing datasets (to validate identified risk models and determine optimal monitoring criteria) and public preferences were used to structure and populate the economic model.

SETTING: Primary and secondary care.

PARTICIPANTS: Adults with ocular hypertension (IOP > 21 mmHg) and the public (surveillance preferences).

INTERVENTIONS: We compared five pathways: two based on National Institute for Health and Clinical Excellence (NICE) guidelines with monitoring interval and treatment depending on initial risk stratification, 'NICE intensive' (4-monthly to annual monitoring) and 'NICE conservative' (6-monthly to biennial monitoring); two pathways, differing in location (hospital and community), with monitoring biennially and treatment initiated for a ≥ 6% 5-year glaucoma risk; and a 'treat all' pathway involving treatment with a prostaglandin analogue if IOP > 21 mmHg and IOP measured annually in the community.

MAIN OUTCOME MEASURES: Glaucoma cases detected; tonometer agreement; public preferences; costs; willingness to pay and quality-adjusted life-years (QALYs).

RESULTS: The best available glaucoma risk prediction model estimated the 5-year risk based on age and ocular predictors (IOP, central corneal thickness, optic nerve damage and index of visual field status). Taking the average of two IOP readings, by tonometry, true change was detected at two years. Sizeable measurement variability was noted between tonometers. There was a general public preference for monitoring; good communication and understanding of the process predicted service value. 'Treat all' was the least costly and 'NICE intensive' the most costly pathway. Biennial monitoring reduced the number of cases of glaucoma conversion compared with a 'treat all' pathway and provided more QALYs, but the incremental cost-effectiveness ratio (ICER) was considerably more than £30,000. The 'NICE intensive' pathway also avoided glaucoma conversion, but NICE-based pathways were either dominated (more costly and less effective) by biennial hospital monitoring or had a ICERs > £30,000. Results were not sensitive to the risk threshold for initiating surveillance but were sensitive to the risk threshold for initiating treatment, NHS costs and treatment adherence.

LIMITATIONS: Optimal monitoring intervals were based on IOP data. There were insufficient data to determine the optimal frequency of measurement of the visual field or optic nerve head for identification of glaucoma. The economic modelling took a 20-year time horizon which may be insufficient to capture long-term benefits. Sensitivity analyses may not fully capture the uncertainty surrounding parameter estimates.

CONCLUSIONS: For confirmed ocular hypertension, findings suggest that there is no clear benefit from intensive monitoring. Consideration of the patient experience is important. A cohort study is recommended to provide data to refine the glaucoma risk prediction model, determine the optimum type and frequency of serial glaucoma tests and estimate costs and patient preferences for monitoring and treatment.

FUNDING: The National Institute for Health Research Health Technology Assessment Programme.

Metabolomic Profiling of In Vivo Plasma Responses to DioxinAssociated Dietary Contaminant Exposure in Rats: Implications for Identification of Sources of Animal and Human Exposure

Dioxin contamination of the food chain typically occurs when cocktails of combustion residues or polychlorinated biphenyl (PCB) containing oils become incorporated into animal feed. These highly toxic compounds are bioaccumulative with small amounts posing a major health risk. The ability to identify animal exposure to these compounds prior to their entry into the food chain may be an invaluable tool to safeguard public health. Dioxin-like compounds act by a common mode of action and this suggests that markers or patterns of response may facilitate identification of exposed animals. However, secondary co-contaminating compounds present in typical dioxin sources may affect responses to compounds. This study has investigated for the first time the potential of a metabolomics platform to distinguish between animals exposed to different sources of dioxin contamination through their diet. Sprague-Dawley rats were given feed containing dioxin-like toxins from hospital incinerator soot, a common PCB oil standard and pure 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (normalized at 0.1 µg/kg TEQ) and acquired plasma was subsequently biochemically profiled using ultra high performance liquid chromatography (UPLC) quadropole time-of-flight-mass spectrometry (QTof-MS). An OPLS-DA model was generated from acquired metabolite fingerprints and validated which allowed classification of plasma from individual animals into the four dietary exposure study groups with a level of accuracy of 97-100%. A set of 24 ions of importance to the prediction model, and which had levels significantly altered between feeding groups, were positively identified as deriving from eight identifiable metabolites including lysophosphatidylcholine (16:0) and tyrosine. This study demonstrates the enormous potential of metabolomic-based profiling to provide a powerful and reliable tool for the detection of dioxin exposure in food-producing animals.

Combination of CFD and DOE to analyse solid particle erosion in elbows

Solid particle erosion is a major concern in the engineering industry, particularly where transport of slurry flow is involved. Such flow regimes are characteristic of those in alumina refinement plants. The entrainment of particulate matter, for example sand, in the Bayer liquor can cause severe erosion in pipe fittings, especially in those which redirect the flow. The considerable costs involved in the maintenance and replacement of these eroded components led to an interest in research into erosion prediction by numerical methods at Rusal Aughinish alumina refinery, Limerick, Ireland, and the University of Limerick. The first stage of this study focused on the use of computational fluid dynamics (CFD) to simulate solid particle erosion in elbows. Subsequently an analysis of the factors that affect erosion of elbows was performed using design of experiments (DOE) techniques. Combining CFD with DOE harnesses the computational power of CFD in the most efficient manner for prediction of elbow erosion. An analysis of the factors that affect the erosion of elbows was undertaken with the intention of producing an erosion prediction model. © 2009 Taylor & Francis.

A Soft Sensor for Viscosity Control of Polymer Extrusion

Viscosity represents a key indicator of product quality in polymer extrusion but has traditionally been difficult to measure in-process in real-time. An innovative, yet simple, solution to this problem is proposed by a Prediction-Feedback observer mechanism. A `Prediction' model based on the operating conditions generates an open-loop estimate of the melt viscosity; this estimate is used as an input to a second, `Feedback' model to predict the pressure of the system. The pressure value is compared to the actual measured melt pressure and the error used to correct the viscosity estimate. The Prediction model captures the relationship between the operating conditions and the resulting melt viscosity and as such describes the specific material behavior. The Feedback model on the other hand describes the fundamental physical relationship between viscosity and extruder pressure and is a function of the machine geometry. The resulting system yields viscosity estimates within 1% error, shows excellent disturbance rejection properties and can be directly applied to model-based control. This is of major significance to achieving higher quality and reducing waste and set-up times in the polymer extrusion industry.