A dynamic convergence control scheme for the solution of the radial equilibrium equation in through-flow analyses

One of the most frequently encountered numerical problems in scientific analyses is the solution of non-linear equations. Often the analysis of complex phenomena falls beyond the range of applicability of the numerical methods available in the public domain, and demands the design of dedicated algorithms that will approximate, to a specified precision, the mathematical solution of specific problems. These algorithms can be developed from scratch or through the amalgamation of existing techniques. The accurate solution of the full radial equilibrium equation (REE) in streamline curvature (SLC) through-flow analyses presents such a case. This article discusses the development, validation, and application of an 'intelligent' dynamic convergence control (DCC) algorithm for the fast, accurate, and robust numerical solution of the non-linear equations of motion for two-dimensional flow fields. The algorithm was developed to eliminate the large extent of user intervention, usually required by standard numerical methods. The DCC algorithm was integrated into a turbomachinery design and performance simulation software tool and was tested rigorously, particularly at compressor operating regimes traditionally exhibiting convergence difficulties (i.e. far off-design conditions). Typical error histories and comparisons of simulated results against experimental are presented in this article for a particular case study. For all case studies examined, it was found that the algorithm could successfully 'guide' the solution down to the specified error tolerance, at the expense of a slightly slower iteration process (compared to a conventional Newton-Raphson scheme). This hybrid DCC algorithm can also find use in many other engineering and scientific applications that require the robust solution of mathematical problems by numerical instead of analytical means

Circadian rhythms of body temperature and metabolic rate in the House Sparrow (\u3ci\u3ePasser domesticus\u3c/i\u3e)

Birds maintain a fairly high body temperature (Tb) compared to most mammals. In order to maintain a high Tb birds must have a high metabolic rate. High daytime energy expenditures are decreased during the night by lowering Tb. In this experiment daily Tb in house sparrows (Passer domesticus) were determined by telemetry methods. Tb (n=6) showed a decrease of 3.00 C from daytime to night time. The average daytime Tb was 42.7 C and night time was 39.7 C. Oxygen consumption (VO2) was measured in an open flow metabolism system. Metabolic rate had a daytime to night time difference of 2.40 O2/g.hr. Thermal conductance (K) decreased from a daytime K of .23 (mL O2.hr)/C to nighttime K of .14 (mL O2/g.hr)/C. At a Tb of 42.7 C the night time energy expenditure would be 38.8 KJ. At 39.7, the average night time Tb for house sparrows (n=6) the energy expenditure is 36.0 KJ. Therefore a house sparrow saves 7% energy in maintaining circadian rhythms. Deeper depressions of Tb, known as torpor, may be energetically efficient, but costly in predation

Theoretical optimal trajectories for reducing the environmental impact of commercial aircraft operations

This work describes initial results obtained from an ongoing research involving the development of optimization algorithms which are capable of performing multi-disciplinary aircraft trajectory optimization processes. A short description of both the rationale behind the initial selection of a suitable optimization technique and the status of the optimization algorithms is firstly presented. The optimization algorithms developed are subsequently utilized to analyze different case studies involving one or more flight phases present in actual aircraft flight profiles. Several optimization processes focusing on the minimization of total flight time, fuel burned and oxides of nitrogen (NOx) emissions are carried out and their results are presented and discussed. When compared with others obtained using commercially available optimizers, results of these optimization processes show atisfactory level of accuracy (average discrepancies ~2%). It is expected that these optimization algorithms can be utilized in future to efficiently compute realistic, optimal and ‘greener’ aircraft trajectories, thereby minimizing the environmental impact of commercial aircraft operations

An experimental and numerical investigation of the effect of aero gas turbine test facility aspect ratio on thrust measurement

This work describes the outcome of research program investigating thrust measurements in enclosed test facility for modern aero gas turbine engines. Literature work, experimental work and a description of Computational fluid dynamics simulation system have been developed to improve the accuracy of test bed thrust measurement. The key parameters covered in the research include test house size in relation to engine size. The effect of the distance of engine to detuner on the thrust correction factor was also investigated. The rule of loss mechanism within the test facility to include intake momentum drag, cradle drag, base drag, recirculation on loss and intake exhaust losses loss. The thrust correction factor prediction technique available in the open literature are compared with the result given by this research and conclusion are drawn. CFD predictions show that the biggest difference with experimental data is only 1 % in TCF for the largest test cell size. For the smallest test cell this difference increases to only 2%. These results in terms of accuracy are lower than what would normally be expected for general CFD work. The major contributions to thrust measurement technology include the following: 1. The research was able to ascertain that as engine size increases it will become more risky to rely on test bed results as giving an accurate prediction of static thrust. 2. The work has enabled confident prediction that test bed results can give test bed static thrust compared to free air testing with an accuracy of one half of 1%. 3. Using Fluent it has been possible to reproduce a comparable comparison with test bed results. This will give the user of the research a higher level of confidence in predicting thrust measurements for test beds whose size is small in comparison with engine size. 4. It is of course an ambition for all those working in the field to eliminate engine testing. However this is unachievable ambition. This research has shown the way to improve CFD prediction towards achieving this ambition. Finally detailed recommendations are given for continuation for this research program.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Sub-idle modelling of gas turbines : altitude relight and windmilling

Gas turbine sub-idle performance modelling is still in an early development stage and this research aims to provide and improve present techniques, for modelling of windmilling and transient windmilling relights, through to groundstart simulations. Engine ATF data was studied and used to align models created within this research for low and high bypass engines, and compare these models simulation results. Methods for the extrapolation of component characteristics are improved and performed in linearised parameter form, and the most efficient approach discussed. The mixer behaviour is analysed and recommendations of off-design mixer behaviour representation in a sub-idle model are proposed and performed within the modelling. Combustion at sub-idle conditions is investigated with regards to the loading parameter definition, and also its representation for the influence of evaporation rate being limiting to overall combustion efficiency. A method is proposed on extrapolating and representation of the combustion characteristic. Compressor behaviour and the blade torques at locked rotor and windmilling conditions are studied using 3D CFD, producing insight and discussion on CFD suitability and what it can offer at these operating conditions. From the CFD studies generic loss coefficients were created for all compressor blades, from which a zero speed is created for the whole compressor, from a theoretical stage stacking calculation. This zero-speed curve is shown to allow interpolation of component characteristics to the sub-idle region, improving the definition and a predictive approach. A windmilling conditions cascade test rig is proposed, designed and built for validating the CFD loss coefficients. The findings and discussions within this thesis provide useful reference material on this complicated and little documented area of research. The modelling and methods proposed, provide great advancement of the research area, along with further integration of the Cranfield UTC in performance with Rolls-Royce.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Capability driven development: an approach to designing digital enterprises

The final publication is available at Springer via http://dx.doi.org/10.1007/s12599-014-0362-0[EN] The need for organizations to operate in changing environments is addressed by proposing an approach that integrates organizational development with information system (IS) development taking into account changes in the application context of the solution. This is referred to as Capability Driven Development (CDD). A meta-model representing business and IS designs consisting of goals, key performance indicators, capabilities, context and capability delivery patterns, is being proposed. The use of the meta-model is validated in three industrial case studies as part of an ongoing collaboration project, whereas one case is presented in the paper. Issues related to the use of the CDD approach, namely, CDD methodology and tool support are also discussed.This work has been partially supported by the EU-FP7 funded project no: 611351 CaaS - Capability as a Service in Digital Enterprises.Berzisa, S.; Bravos, G.; Cardona Gonzalez, T.; Czubayko, U.; España, S.; Grabis, J.; Henkel, M.... (2015). Capability driven development: an approach to designing digital enterprises. Business and Information Systems Engineering. 57(1):15-25. https://doi.org/10.1007/s12599-014-0362-0S1525571ArchiMate (2013) An enterprise modeling language from the Open Group. http://www.opengroup.org/archimate/ . Accessed 3 Dec 2014Asadi M, Ramsin R (2008) MDA-based methodologies: an analytical survey. In: Proceedings Model driven architecture – foundations and applications (ECMDA-FA 2008), LNCS 5095, pp 419–431Barney JB (1991) Firm resources and sustained competitive advantage. J Manag 17(1):99–120Bērziša S, Bravos G, Gonzalez Cardona T, Czubayko U, España S, Grabis J, Henke lM, Jokste L, Kampars J, Koc H, Kuhr J, Llorca C, Loucopoulos P, Juanes Pascua lR, Sandkuh lK, Simic H, Stirna J, Zdravkovic J (2014) Deliverable 1.4: Requirements specification for CDD, CaaS – capability as a service for digital enterprises. FP7 project no 611351, Riga Technical University, Latvia. Submitted for reviewBubenko JA Jr, Persson A, Stirna J (2001) User guide of the knowledge management approach using enterprise knowledge patterns. Deliverable D3, IST programme project hypermedia and pattern based knowledge management for smart organisations. project no. IST-2000-28401, Royal Institute of Technology, SwedenBriand LC, Yue T, Labiche Y (2011) A systematic review of transformation approaches between user requirements and analysis models. Requir Eng 16:75–99De Kinderen S, Gordijn J, Akkermans H (2009) Reasoning about customer needs in multi-supplier ICT service bundles using decision models. In: Proceedings 11th international conference on enterprise information systems (ICEIS 2009), pp 131–136Deloitte (2009) Cloud computing: forecasting change. Deloitte Consulting, New York. http://public.deloitte.no/dokumenter/2_Cloud_Computing%5B1%5D.pdf . Accessed 3 Dec 2014Dey A (2001) Understanding and using context. Pers Ubiquitous Comput 5(1):4–7Gamma E, Helm R, Johnson R, Vlissides J (1995) Design patterns: elements of reusable object-oriented software architecture. Addison-Wesley, BostonGomes D, Gonçalves JM, Santos R, Aguiar R (2010) XMPP based context management architecture. In: Proceedings GLOBECOM workshop, IEEE, pp 1372–1377González A, España S, Ruiz M, Pastor Ó (2011) Systematic derivation of class diagrams from communication-oriented business process models. In: 12th working conference on business process modeling, development, and support (BPMDS’11). Springer LNBIP 81, pp 246–260Henkel M, Stirna J (2010) Pondering on the key functionality of model driven development tools: the case of mendix. In: Forbrig P, Günther H (eds) Proceedings business informatics research (BIR 2010), Springer LNBIP 64, pp 146–160Hervas R, Bravo J, Fontecha J (2010) A context model based on ontological languages – a proposal for information visualisation. J Univers Comput Sci 16(12):1539–1555Jarke M, Loucopoulos P, Lyytinen K, Mylopoulos J, Robinson W (2011) The brave new world of design requirements. Information Syst 36(7):992–1008Kaplan RS, Norton DP (2004) Strategy maps: converting intangible assets into tangible outcomes. Harvard Business School Press, BostonKleppe A, Warmer J, Bast W (2013) MDA explained. Addison-Wesley, BostonLoniewski G, Insfran E, Abrahao L (2010) A systematic review of the use of requirements engineering techniques in model-driven development. In: Proceedings model driven engineering languages and systems (MODELS 2010), Part II, LNCS 6395, pp 213–227Mohagheghi P, Dehlen V (2008) Where is the proof? - a review of experiences from applying MDE in industry. In: Proceedings model driven architecture – foundations and applications (ECMDA-FA 2008). LNCS 5095. Springer, Heidelberg, pp 432–443Nilsson AG, Tolis C, Nellborn C (eds) (1999) Perspectives on business modelling: understanding and changing organisations. Springer, HeidelbergOASIS (2011) Reference architecture foundation for service oriented architecture version 1.0, committee specification draft 03/public review draft 02 06 July 2011. http://docs.oasis-open.org/soa-rm/soa-ra/v1.0/soa-ra.pdf . Accessed 3 Dec 2014OMG (2011a) UML superstructure. http://www.omg.org/spec/UML/2.4.1/ . Accessed 3 Dec 2014OMG (2011b) Business process model and notation. http://www.omg.org/spec/BPMN/2.0/ . Accessed 3 Dec 2014Osterwalder A, Pigneur Y (2003) Modeling value propositions in e-business. Proc 5th international conference on electronic commerce (ICEC 2003). ACM Conference Proceedings Series 50Papazoglou MP, Yang J (2002) Design methodology for web services and business processes. In: Proceedings 3rd international workshop on technologies for e-services (TES 03). LNCS 2444. Springer, Heidelberg, pp 54–64Pastor O, Giachetti G (2010) Linking goal-oriented requirements and model-driven development. In: Intentional perspectives on information systems engineering. Springer, Heidelberg, pp 257–276Porter ME (1985) Competitive advantage: creating and sustaining superior performance. Free Press, New YorkRuiz M, Costal D, España S, Franch X, Pastor Ó (2014) Integrating the goal and business process perspectives in information system analysis. In: 26th International Conference on Advanced Information Systems Engineering (CAiSE 2014). LNCS 8484. Springer, Heidelberg, pp 332–346Sheng Q, Yu J, Dustar S (eds) (2010) Enabling context-aware web services: methods, architectures, and technologies. Chapman & Hall/CRC, Boca RatonSmanchat S, Ling S, Indrawan M (2008) A survey on context-aware workflow adaptations. In: Proceedings 6th international conference on advances in mobile computing and multimedia (MoMM 2008), New York, pp 414–417Stirna J, Grabis J, Henkel M, Zdravkovic J (2012) Capability driven development – an approach to support evolving organizations. In: The practice of enterprise modeling (PoEM 2012). LNBIP 134. Springer, Heidelberg, pp 117–131Vale S, Hammoudi S (2009) COMODE: a framework for the development of context-aware applications in the context of MDE. In: Proceedings 4th international conference on internet and web applications and services (ICIW 2009). IEEE, Venice, pp 261–266Wesenberg H (2011) Enterprise modeling in an agile world. In: Johannesson P, Krogstie J, Opdahl AL (eds) The practice of enterprise modeling (PoEM 2011). LNBIP 92. Springer, Heidelberg, pp 126–130Zdravkovic J, Stirna J, Henkel M, Grabis J (2013) Modeling business capabilities and context dependent delivery by cloud services. In: Proceedings advanced information systems engineering (CAiSE 2013). LNCS 7908. Springer, Heidelberg, pp 369–38

an individual participant data meta-analysis

Background The impact of neuraminidase inhibitors (NAIs) on influenza-related pneumonia (IRP) is not established. Our objective was to investigate the association between NAI treatment and IRP incidence and outcomes in patients hospitalised with A(H1N1)pdm09 virus infection. Methods A worldwide meta- analysis of individual participant data from 20 634 hospitalised patients with laboratory-confirmed A(H1N1)pdm09 (n = 20 021) or clinically diagnosed (n = 613) ‘pandemic influenza’. The primary outcome was radiologically confirmed IRP. Odds ratios (OR) were estimated using generalised linear mixed modelling, adjusting for NAI treatment propensity, antibiotics and corticosteroids. Results Of 20 634 included participants, 5978 (29·0%) had IRP; conversely, 3349 (16·2%) had confirmed the absence of radiographic pneumonia (the comparator). Early NAI treatment (within 2 days of symptom onset) versus no NAI was not significantly associated with IRP [adj. OR 0·83 (95% CI 0·64–1·06; P = 0·136)]. Among the 5978 patients with IRP, early NAI treatment versus none did not impact on mortality [adj. OR = 0·72 (0·44–1·17; P = 0·180)] or likelihood of requiring ventilatory support [adj. OR = 1·17 (0·71–1·92; P = 0·537)], but early treatment versus later significantly reduced mortality [adj. OR = 0·70 (0·55–0·88; P = 0·003)] and likelihood of requiring ventilatory support [adj. OR = 0·68 (0·54–0·85; P = 0·001)]. Conclusions Early NAI treatment of patients hospitalised with A(H1N1)pdm09 virus infection versus no treatment did not reduce the likelihood of IRP. However, in patients who developed IRP, early NAI treatment versus later reduced the likelihood of mortality and needing ventilatory support

Preparation, characterization, and pharmacological activity of Cymbopogon winterianus Jowitt ex Bor (Poaceae) leaf essential oil of B-cyclodextrin inclusion complexes

This study aimed to evaluate the orofacial antinociceptive effect of the Cymbopogon winterianus essential oil (LEO) complexed in B-cyclodextrin (LEO-CD) and to assess the possible involvement of the central nervous system (CNS). The LEO was extracted, chromatographed, and complexed in B-cyclodextrin. The complex was characterized by differential scanning calorimetry (DSC) and thermogravimetry derivative (TG/DTG). Male Swiss mice (2-3 months) were treated with LEO-CD (50–200 mg/kg, p.o.), vehicle (distilled water, p.o.), or standard drug (i.p.) and subjected to the orofacial nociception formalin-, capsaicin-, and glutamateinduced. After the formalin test, the animals were perfused and the brains subjected to immunofluorescence for Fos. The rota-rod test (7 rpm/min) was carried out. Geraniol (37.57%) was the main compound of LEO. DSC and TG/DTG proved the complexation. The orofacial nociceptive behavior was significantly (p < 0.05) reduced. The number of Fos-positive cells was significantly changed in the dorsal raphe nucleus (p < 0.01), locus coeruleus (p < 0.001), trigeminal nucleus (p < 0.05), and trigeminal thalamic tract (p < 0.05). LEO-CD did not cause changes in motor coordination in the rota-rod test. Thus, our results suggested that LEO-CD has an orofacial antinociceptive profile, probably mediated by the activation of the CNS without changing the motor coordination

CNS Penetration of Intrathecal-Lumbar Idursulfase in the Monkey, Dog and Mouse: Implications for Neurological Outcomes of Lysosomal Storage Disorder

A major challenge for the treatment of many central nervous system (CNS) disorders is the lack of convenient and effective methods for delivering biological agents to the brain. Mucopolysaccharidosis II (Hunter syndrome) is a rare inherited lysosomal storage disorder resulting from a deficiency of iduronate-2-sulfatase (I2S). I2S is a large, highly glycosylated enzyme. Intravenous administration is not likely to be an effective therapy for disease-related neurological outcomes that require enzyme access to the brain cells, in particular neurons and oligodendrocytes. We demonstrate that intracerebroventricular and lumbar intrathecal administration of recombinant I2S in dogs and nonhuman primates resulted in widespread enzyme distribution in the brain parenchyma, including remarkable deposition in the lysosomes of both neurons and oligodendrocytes. Lumbar intrathecal administration also resulted in enzyme delivery to the spinal cord, whereas little enzyme was detected there after intraventricular administration. Mucopolysaccharidosis II model is available in mice. Lumbar administration of recombinant I2S to enzyme deficient animals reduced the storage of glycosaminoglycans in both superficial and deep brain tissues, with concurrent morphological improvements. The observed patterns of enzyme transport from cerebrospinal fluid to the CNS tissues and the resultant biological activity (a) warrant further investigation of intrathecal delivery of I2S via lumbar catheter as an experimental treatment for the neurological symptoms of Hunter syndrome and (b) may have broader implications for CNS treatment with biopharmaceuticals