Academic literature on the topic 'Linee guida EULAR'

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Journal articles on the topic "Linee guida EULAR"

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Maldonado, Ana Luisa P., and R. Jeremy Astley. "SwirlProp: A tool for sound propagation and attenuation in swirling flows." International Journal of Aeroacoustics 20, no. 5-7 (September 2021): 588–609. http://dx.doi.org/10.1177/1475472x211052591.

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The current trends for next generation turbofan engines are towards shorter nacelles and increased distances between the fan and the outlet guide vanes. This leads to an overall reduction in lined surface areas as well as an increase in the relative importance of the interstage liner, which is the liner placed between the rotor blades and the stator vanes. So far most of the efforts have been on liners for intakes and bypass ducts. The interstage is different in that the liner is subject to a mean flow with a strong swirl component and shear. The SwirlProp code was developed to contribute to understanding and predicting the effect of the swirl on liner attenuation. The code is based on the linearized Euler equations together with the Ingard–Myers boundary condition. An eigenvalue problem is formulated and discretized using a finite difference method. The code is exhaustively compared against predicted values obtained by other methods for uniform, sheared and swirling mean flows and hard-walled and lined ducts. A cross-validation between SwirlProp and an in-house code from Rolls-Royce was carried out for a more realistic case. Also, details on the implementation of the boundary condition are proposed and details are presented.
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Luz, Saturnino, and Masood Masoodian. "A comparison of linear and mosaic diagrams for set visualization." Information Visualization 18, no. 3 (February 7, 2018): 297–310. http://dx.doi.org/10.1177/1473871618754343.

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Linear diagrams have been shown to compare favourably to better known forms of set visualization, such as Venn and Euler diagrams, in supporting non-interactive assessment of set relationships. Recent studies that compared several variants of linear diagrams have demonstrated that users perform best at tasks involving identification of intersections, disjointness and subsets when using a horizontally drawn linear diagram with thin lines representing sets and employing vertical lines as guide lines. The essential visual task the user needs to perform in order to interpret this kind of diagram is vertical alignment of parallel lines and detection of overlaps. Space-filling mosaic diagrams which support this same visual task have been used in other applications, such as the visualization of schedules of activities, where they have been shown to be superior to linear Gantt charts. In this article, we present an experimental comparison of linear and mosaic diagrams for visualization of set relationships, in terms of accuracy, time-to-answer and subjective ratings of perceived task difficulty. The findings show that the two visualizations are largely similar with respect to these measures, suggesting that the choice of one or the other may be solely guided by other visual design considerations. Mosaic diagrams might be more suitable, for instance, in cases where miniature diagrams representing overviews of relations in different collections of sets are required, such as in small-multiples displays.
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Telegin, A. I. "Formalism of Writing Out of Manipulators Dynamic Equation." Bulletin of the South Ural State University. Ser. Computer Technologies, Automatic Control & Radioelectronics 21, no. 4 (November 2021): 52–68. http://dx.doi.org/10.14529/ctcr210405.

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The problem of cumbersome equations of dynamics for manipulation systems of industrial robots (manipulators) with translational and rotational joints is solved. A new formalism for writing out the equations of dynamics of manipulators by using of guide cosines is proposed. Examples of writing out equations of dynamics of manipulators with guid cosines are given. The equations of dynamics in relative angles of rotation of bodies are obtained with the help of these guide cosines by applying their properties. These manipulators have from three to six degrees of freedom. In their equations of dynamics the geometric, kinematic, static and inertial parameters are explicit. The multipliers for accelerations and products of velocities are optimal in the sense of the minimum of arithmetic operations (additions and multiplications) that are needed for their calculations in the written out equations of dynamics. JS-code and method for verification of the equations of dynamics of manipulators written in analytical form are proposed. The problem is that when the equations are written out manually, errors and oversights in the intermediate entries and the final result are possible. Therefore it is necessary to check the results of writing out for absence of errors, i.e. to perform verification of formulas for calculation of constitutive equations of dynamics. To do this, we can use software designed to calculate the generalized driving forces of manipulators, i.e. to solve the first problem of dynamics. Such software is offered as a web-application, in which JS-function is used for verification of the equations of dynamics of manipulators. The method of verification of formulas to calculate the generalized forces of gravity and multipliers (coefficients) for generalized accelerations and products of generalized velocities in the equations of dynamics is developed. An example of verification of the equations of dynamics of the universal manipulator with six degrees of freedom in space is given. Aim. The aim of research is to develop a formalism for writing out the analytical form of the equations of the manipulators’ dynamics in the guide cosines of the principal axes of the coupled body coordinate systems, whose coefficients contain the minimum number of arithmetic operations. Research methods. The methods of research refer to vector and analytic mechanics of absolutely solid systems, to vector algebra, and to systems analysis and programming in scripting languages. Results. The results contain two proved statements, in which there are the formulas and the methodology that allow us to write manually the equations of dynamics of manipulators with three and six degrees of mobility both in guiding cosines and in generalized coordinates. In both cases it is impossible to simplify the obtained equations. Conclusion. The offered analytical types of the equations of dynamics occupy several lines. By the known classical formalisms (Lagrange, Appel, Nielsen, Newton-Euler, etc.) it is practically impossible to obtain similar results because of the large number of complex mathematical operations in their implementation and the cumbersomeness of the resulting formulas.
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Rollefstad, S., E. Ikdahl, J. Sexton, G. Kitas, P. Van Riel, C. S. Crowson, I. Graham, and A. G. Semb. "OP0121 MANAGEMENT OF DYSLIPIDAEMIA AND HYPERTENSION IN PATIENTS WITH RHEUMATOID ARTHRITIS – DATA FROM 19 COUNTRIES." Annals of the Rheumatic Diseases 79, Suppl 1 (June 2020): 80.2–80. http://dx.doi.org/10.1136/annrheumdis-2020-eular.4236.

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Background:The realisation that subjects with rheumatoid arthritis (RA) are at increased risk of cardiovascular disease (CVD) has led to a growing interest in risk factor control in such people, but whether this has influenced the management of dyslipidaemia and hypertension (HT) is uncertain. In subjects with coronary heart disease (CHD), audits of CVD risk factor control are regularly performed, which makes it possible to evaluate guideline implementation over time.1Updated surveys on CVD risk management in patients with RA are needed.Objectives:To describe differences in lipid and blood pressure (BP) levels among patients with RA from five world regions. Furthermore, to evaluate attainment of guideline recommended targets for lipid lowering and antihypertensive treatment.Methods:The SUrvey of CVD Risk Factors in patients with RA (SURF-RA) was conducted at 53 centres in 19 countries from 2014 to 2019. Data including demographics, RA disease characteristics, CVD comorbidity, risk factors and use of preventive treatment was collected. HT was defined as self-reported HT, and/or measured BP ≥140/90 mmHg, and/or use of anti HT medication (a-HT). The treatment goal of a-HT was BP <140/90 mmHg. The 10-year risk of a fatal CVD event was calculated by the European CVD risk calculator, the Systematic COronary Risk Evaluation (SCORE), and was thereafter multiplied with 1.5 as recommended by the European League Against Rheumatism. Patients were classified in a high or very high CVD risk group according to the 2012 European Society of Cardiology guidelines, with low density lipoprotein cholesterol (LDL-c) goal at <2.6 and <1.8 mmol/L, respectively.2Results:In total, 14503 RA patients were included. The mean age was 59.8±13.6 years, and it was a strong female preponderance (74%). Nearly 2/3 of the patients were hypertensive. Use of a-HT in the total population differed substantially between the cohorts with limited use in West Europe and Latin America (17.4% and 24.8%), in contrast to North America and East Europe (46.8% and 57.0%). On average, half of those with HT were at the recommended BP goal. The lowest BP goal attainment was seen in Asia, West and East Europe (40.8-43.1%), and the highest in North America (63.5%). Overall 51.5% had an indication for lipid lowering therapy (LLT), and of these 43.5% were taking LLT. Only 34.0% of patients with an indication for LLT were at recommended LDL-c goals. The proportion of RA patients on target for LDL-c varied greatly between regions, from 23.1% in East Europe to 51.0% in North America. The LDL-c goal attainment was higher in RA patients at high risk (45.1%) compared to those at very high risk of CVD (18.0%).Conclusion:This large international survey on RA patients revealed considerable geographical differences in CVD preventive treatment. Lower goal attainment for LLT than reported for subjects with CHD was observed. We conclude that there is a substantial need for improvement in CVD preventive measures in RA patients.References:[1]De Backer G, Jankowski P, Kotseva K,et al.Management of dyslipidaemia in patients with coronary heart disease: Results from the ESC-EORP EUROASPIRE V survey in 27 countries.Atherosclerosis. 2019;285:135-146.[2]Perk J, De Backer G, Gohlke H,et al.European Guide-lines on cardiovascular disease prevention in clinical practice.Eur Heart J.2012:1635-701.Disclosure of Interests:Silvia Rollefstad: None declared, Eirik Ikdahl: None declared, Joe Sexton: None declared, Georeg Kitas: None declared, Piet van Riel: None declared, Cynthia S. Crowson Grant/research support from: Pfizer research grant, Ian Graham: None declared, Anne Grete Semb: None declared
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Rodriguez-García, S. C., E. Toledano Martinez, M. J. García de Yébenes, L. Carmona, and I. González-Álvaro. "AB0120 IDENTIFYING CORE VARIABLES TO DEVELOP A SEVERITY INDEX IN RHEUMATOID ARTHRITIS: A NATIONWIDE DELPHI CONSENSUS." Annals of the Rheumatic Diseases 80, Suppl 1 (May 19, 2021): 1089. http://dx.doi.org/10.1136/annrheumdis-2021-eular.1821.

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Background:Early interventions during the “window of opportunity” have been shown to improve clinical outcomes in rheumatoid arthritis (RA). However, intensive treatment can induce toxicity so identifying patients most likely to benefit from it is of great importance. Hence, tools for guiding therapeutic decisions in early disease stages are needed.Objectives:To identify core variables to develop a RA severity index according to an expert panel.Methods:An expert panel was prompted to analyze relevant variables to define a “severity” construct, specified as “early severe disease”, able to classify patients with data collected on the first 2 years of the disease. They were also asked to identify potential modifying factors and external criteria to evaluate criterion validity.An anonymous nationwide 2-round Delphi survey was applied to look for consensus about: (1) the priority of inclusion of each variable, (2) the feasibility to obtain them from usual sources (e.g., medical records) and (3) their definition. Each item was rated on a 10-point (priority) or 5-point (feasibility and definition) Likert scales were 0=complete disagreement and 5-10=complete agreement.After the 1st round, any item rated from 5 to 10 in priority and 3 to 5 for feasibility by at least 70% of responders was included in the final variable list. Items not reaching at least 20% consensus were discarded. The remaining ones would be voted again in the 2nd round and adopted if they reached at least 50% consensus or else discarded.Results:The task force identified 17 variables to define the “severity” construct (Table 1). Socio-economic status, knowledge of their own disease, type or work adherence to treatment, among others were proposed modifying factors. Rheumatoid factor or anti-citrullinated peptide antibody seropositivity as predictive factors The physician global assessment and the “burden of treatment” (lines of treatment, number and dose of DMARDs and cumulative steroid dose received) were proposed for evaluating criterion validity.A total of 61 stakeholders from across Spain took the survey, 56% were female and had 19.8 years of average experience after training. All variables were included after 1st round. Nonetheless, definitions were submitted for a 2nd round after rephrasing, including comments received on the survey. The final list was reduced to 15 items after merging 3 of the initial variables into a new one called “refractoriness”(Table 1).Conclusion:The consensus process resulted in a list of variables and modifying factors deemed of relevance for the severity construct as we defined it. These items will be used to develop a severity index to guide treatment decisions in early disease stages.Table 1.Variables proposed for the severity construct.NInitially proposed variablesNFinal variables after Delphi1Polyarthritis1Polyarthritis2Big joint involvement2Big joint involvement3High disease activity at 2 years of follow-up3High disease activity at 2 years of follow-up4Maintained disease activity in the first 2 years4Maintained disease activity in the first 2 years5Acute phase reactants persistently elevated5Acute phase reactants persistently elevated6Extra-articular manifestations6Extra-articular manifestations7Failure to reach remission7Failure to reach remission8Need for aggressive therapy in the first 2 years8Need for aggressive therapy in the first 2 years9Presence of erosions at diagnosis9Presence of erosions by at diagnosis10Number of erosions at 2 years of follow-up10Number of erosions at 2 years of follow-up11Lack of improvement in the HAQ-DI11Lack of improvement in the HAQ-DI12Need for prosthetic surgery12Need for prosthetic surgery13Hospital Admissions13Hospital Admissions14Cortico-dependence14Cortico-dependence15MTX withdrawal due to loss of efficacy15Refractoriness16Completely absent response to MTX17Number of drugs with lack of efficacyUnderlined variables on the left were merged into a new variable called “Refractoriness”. HAQ-DI: Health Assessment Questionnaire-Disability IndexDisclosure of Interests:Sebastián C Rodriguez-García Speakers bureau: Roche, Sanofi, MSD, UCB-Pharma, Bristol-Myers-Squibb, Novartis, janssen, Consultant of: Bristol-Myers-Squibb, Galapagos, ESTHER TOLEDANO MARTINEZ: None declared, María Jesús García de Yébenes: None declared, Loreto Carmona Grant/research support from: Novartis Farmacéutica, SA, Pfizer, S.L.U., Merck Sharp & Dohme España, S.A., Roche Farma, S.A, Sanofi Aventis, AbbVie Spain, S.L.U., and Laboratorios Gebro Pharma, SA, Isidoro González-Álvaro Speakers bureau: Abbvie, MSD, Roche, Lilly, Paid instructor for: Lilly, Consultant of: Lilly, Sanofi, Grant/research support from: Roche
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Dissertations / Theses on the topic "Linee guida EULAR"

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ZANETTI, ANNA. "The management of patients with rheumatoid arthritis: an overview of obstacles and improvement strategies." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/365542.

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L’artirite reumatoide (AR) è la più diffusa patologia autoimmune in Italia con elevati costi terapeutici e previdenziali associati. Questa patologia colpisce circa lo 0.5-1% della popolazione adulta, prevalentemente di genere femminile. Essendo una patologia degenerativa, i cui danni sono frequentemente irreversibili, una diagnosi precoce così come un adeguato trattamento ed un elevato livello di compliance del paziente allo stesso, potrebbero rallentare il peggioramento della malattia. Inoltre sono poco noti i possibili effetti della malattia e del suo trattamento sulle gravidanze e i successivi outcome gravidici. I principali obiettivi della tesi quindi sono: i) valutare l’aderenza alle linee guida per il trattamento dell’ AR da parte dei clinici, ii) valutare l’aderenza al trattamento per AR da parte del paziente, iii) stimare costo ed efficacia delle cure erogate nelle cliniche specializzate per il trattamento di pazienti con AR, iv) analizzare gli esiti gravidici e il raggiungimento della gravidanza in donne con AR trattate con metotrexate (MTX). La prima tematica ha riguardato la valutazione di come sono state implementate le linee guida della European Alliance of Associations for Rheumatology (EULAR) per il trattamento dell’AR e l’impatto dell’aderenza a queste linee guida sulla probabilità di ospedalizzazione. I principali risultati di questo studio hanno mostrato come i pazienti con un’ottima aderenza alle linee guida, se confrontati con quelli con bassa aderenza, abbiano un rischio del 24% inferiore di incorrere in ospedalizzazione. La seconda tematica ha riguardato la valutazione dell’impatto dell’aderenza al trattamento con Disease-Modifying Anti-Rheumatic Drugs (DMARDs), terapia suggerita dall’EULAR, sul raggiungimento della remissione clinica di malattia. I dati provengono dal database ELECTRA (con informazioni cliniche e provenienti da database amministrativi) di pazienti con AR trattati presso l’IRCCS Policlinico San Matteo (Pavia). Si è osservato che un incremento percentuale di 10 unità nella copertura al trattamento comporta un aumento della probabilità di remissione clinica del 10%. Da questi risultati sembra emergere l’importanza di riuscire a monitorare i pazienti nella pratica clinica per mantenere elevati standard di compliance. L’obiettivo della terza tematica si è focalizzato su una valutazione costo-efficacia del trattamento dei pazienti con AR erogato da cliniche specializzate (EAC), confrontandolo con quello dei pazienti trattati in cliniche non specializzate. Sono state quindi reclutate due coorti, la prima di pazienti trattati in una EAC e l’altra estratta dai database amministrativi di regione lombardia tra i soli soggetti con AR. I risultati principali di questa terza fase hanno mostrato come ad un incremento moderato dei costi si associ un incremento molto elevato dell’efficacia, specialmente se calcolata come durata di degenza e come aderenza alle linee guida EULAR. La quarta ed ultima tematica riguarda l’analisi dell’impatto del trattamento con MTX (DMARD suggerito dall’EULAR come prima linea di trattamento) nelle pazienti con AR sulla possibilità di raggiungere una gravidanza e sugli outcome gravidici conseguenti. Sono state definite tre coorti: donne con AR con esposizione incidente di MTX, donne con AR senza trattamento con MTX e donne senza AR. I risultati principali di questa analisi hanno mostrato che le donne con AR, specialmente se trattate con MTX, hanno una minor frequenza di gravidanze rispetto alle donne senza AR. Inoltre, le donne trattate con MTX sembrano avere un rischio più elevato di aborto spontaneo (circa due volte superiore) rispetto alle altre due coorti.
Rheumatoid arthritis (RA) is, in Italy, the most widespread autoimmune disease with high associated costs for the National Health Service. This disease affects about 0.5-1% of the adult population, mainly of the female gender. Being a degenerative disease, whose damages are frequently irreversible, an early diagnosis as well as an adequate treatment and a high level treatment compliance of the patient, could slow down the worsening of the disease. Furthermore, the possible effects of RA and its treatment on pregnancies and subsequent pregnancy outcomes are not well known. The main objectives of the thesis are therefore: i) to evaluate the adherence to guidelines for the treatment of RA, ii) to evaluate the patient's adherence to RA treatment, iii) to estimate the cost and effectiveness of care provided in specialized clinics for the treatment of RA patients, iv) to analyze pregnancy outcomes and the likelihood of achieving pregnancy in women with RA treated with methotrexate (MTX). The first issue concerned the assessment of how the guidelines of the European Alliance of Associations for Rheumatology (EULAR) for the treatment of RA have been implemented, and the impact of adherence to these guidelines on the probability of hospitalization. The main results of this study showed that patients with excellent adherence to guidelines, when compared with those with low adherence, have a 24% lower risk of hospitalization. The second topic concerned the evaluation of the impact of adherence to treatment with Disease-Modifying Anti-Rheumatic Drugs (DMARDs), the therapy suggested by EULAR, on the achievement of disease clinical remission (defined as a substantial decrease or absence of symptoms). The ELECTRA database, which contains clinical information and information from administrative databases of RA patients treated at the IRCCS Policlinico San Matteo (Pavia), was considered for the analysis. The main finding showed that a 10-unit percentage increase in proportion of days covered by DMARDs is associated with a 10% increase in the likelihood of clinical remission. These results show the importance of monitoring patients in clinical practice to maintain high levels of treatment compliance. The objective of the third theme focused on a cost-effectiveness evaluation, comparing RA patients treated in specialized clinics ("Early Arthritis Clinic" - EAC), with RA patients treated in non-specialized clinics. Two cohorts were recruited, the first one included patients treated in the EAC of the IRCCS Policlinico San Matteo and the other one with patients with RA extracted from the administrative databases of Lombardy region. The main results of this third phase showed that a moderate increase in costs is associated with a very high increase in effectiveness, especially if calculated as length of hospitalizations and as adherence to the EULAR guidelines. These findings could open up new scenarios in RA patient management. The fourth and final topic concerned the impact of treatment with MTX (DMARD suggested by EULAR as the first line of treatment) in RA women, on the likelihood of achieving pregnancy and on pregnancy outcomes. Three cohorts were recruited: women with RA with incident MTX exposure, women with RA without MTX treatment, and women without RA. The main results of this analysis showed that women with RA, especially when treated with MTX, have a lower frequency of pregnancies than women without RA. Furthermore, women treated with MTX have a higher risk of spontaneous abortion (about twice as high) than the other two cohorts.
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Conference papers on the topic "Linee guida EULAR"

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Pa´scoa, J. C., A. C. Mendes, and L. M. C. Gato. "Redesigning Annular Turbine Blade Rows Using a Viscous-Inviscid Inverse Design Method." In ASME Turbo Expo 2008: Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-50313.

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This paper presents the results of the aerodynamic redesign of an annular turbine blade row. The inverse method herein applied is an extension to 3D of an iterative inverse design method based on the imposition of the blade load, thickness distribution and stacking line. We define a mass-averaged mean tangential velocity over one blade pitch, ru¯θ, as the main design variable, since its derivative is related to the aerodynamic load. A time-lagged formulation for the 3D camber surface generator is given in order to include the blade thickness distribution into the design algorithm. The hybrid viscous-inviscid design code comprises three main components: the blade update algorithm; a fast inviscid 3D Euler code; and a viscous analysis code. The blade geometry and flow conditions are typical of LP turbine nozzle guide vanes. The design method will demonstrate its ability to redesign blade rows that achieve lower flow losses and a more uniform exit flow angle distribution. The performance of the new blades is checked by means of a Navier-Stokes computation using the κ–ε turbulence model. The presented results show a minor decrease in the losses and a better redistribution of the exit flow angle.
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Gastaldi, Chiara, and Muzio M. Gola. "Platform Centered Reduction: A Process Capturing the Essentials for Blade-Damper Coupled Optimization." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-16317.

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Abstract The purpose of this document is to continue along the line of research of the authors in the direction of developing an attractive tool for designers in the initial design phase of the damping of the turbomachinery blades. In particular, in order to guide their initial choice of a dry friction underplatform damper in the most appropriate way. The paper shows how, to this purpose, certain reasonable simplifications are introduced in the procedure and in the model, leaving the customary full high fidelity computations to the final design verification analysis. The key simplifications here considered are: – the blade neck is modelled with Euler beam finite elements so to speed up the updating of its dimensions during the optimisation process; – the contact forces exerted by the dampers on the two sides of the blade platform are represented by the resultant forces and moments applied to a reference point on the platform, associated to its displacements and rotations; – as an improvement to the model proposed in the paper presented at Turbo Expo 2019, the airfoil is now obtained from a full 3D FE model after a component mode synthesis reduction; this choice is justified by the facts that the airfoil is by large the item with most complex shape and that during the coupled optimization of the damper the airfoil is considered to be of fixed shape. It is shown that the process captures the essentials of the nonlinear dynamics of the blade-damper problem without sacrificing in any way the accuracy of the results. This hybrid model is then employed in the process where the domains of optimal matching between the damper and the blade is searched for by exploring the influence of blade neck thickness (flexibility) and damper mass. Such a purposely simplified process allows a clear identification of relationships between relevant blade features and response with a focus on fatigue life. At the same time, it allows an assessment of the interplay between blade parameters and damper parameters in determining the modal features and the damping capabilities. It is shown how different matching solutions may be identified depending on the expected forcing level on the blade.
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Fredrick, Nicholas, and Milt Davis. "Investigation of the Effects of Inlet Swirl on Compressor Performance and Operability Using a Modified Parallel Compressor Model." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-45553.

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Serpentine ducts used by both military and commercial aircraft can generate significant flow angularity and total pressure distortion at the engine face. Most low by-pass ratio turbofan engines with mixed exhaust are equipped with inlet guide vanes (IGV) which can reduce the effect of moderate inlet distortion. High by-pass ratio and some low by-pass ratio turbofan engines are not equipped with IGVs, and swirl can in effect change the angle of attack of the fan blades. Swirl and total pressure distortion at the engine inlet will impact engine performance, operability, and durability. The impact on the engine performance and operability must be quantified to ensure safe operation of the aircraft and propulsion system. Testing is performed at a limited number of discrete points inside the propulsion system flight envelope where it is believed the engine is most sensitive to the inlet distortion in order to quantify these effects. Turbine engine compressor models are based on the limited amount of experimental data collected during testing. These models can be used as an analysis tool to improve the effectiveness of engine testing and to improve understanding of engine response to inlet distortion. The Dynamic Turbine Engine Compressor Code (DYNTECC) utilizes parallel compressor theory and quasi-one-dimensional Euler equations to determine compressor performance. In its standard form, DYNTECC uses user supplied characteristic stage maps in order to calculate stage forces and shaft work for use in the momentum and energy equations. These maps were typically developed using experimental data or created using characteristic codes such as the 1-D Mean Line Code (MLC) or the 2-D Streamline Curvature Code. The MLC was created to calculate the performance of individual compressor stages and requires less computational effort than the 2-D and 3-D models. To improve efficiency and accuracy, the MLC has been incorporated into DYNTECC as a subroutine. Rather than independently developing stage maps using the MLC and then importing these maps into DYNTECC, DYNTECC can now use the MLC to develop the required stage characteristic for the desired operating point. This will reduce time and complexity required to analyze the effects of inlet swirl on compressor performance. The combined DYNTECC/MLC was used in the past to model total pressure distortion. This paper presents the result obtained using the combined DYNTECC/MLC to model the effects of various types of inlet swirl on F109 fan performance and operability for the first time.
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