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Introducción: Las fracturas diafisarias y distales de tibia son lesiones frecuentes en personas jóvenes que sufren un trauma de alta energía y en ancianos por un trauma de baja energía. El objetivo de este estudio fue comparar el tiempo quirúrgico, el uso de radioscopia, la evaluación funcional y el dolor en el tratamiento de fracturas diafisarias y distales de tibia mediante una técnica suprarrotuliana y una infrarrotuliana. Materiales y Métodos: Se realizó un estudio retrospectivo entre marzo de 2018 y octubre de 2019. La información de los pacientes se obtuvo de la historia clínica electrónica. Se incluyó a pacientes con fracturas diafisarias y distales de tibia. Se estudiaron y compararon los tiempos de radioscopia y de cirugía. El dolor posoperatorio se evaluó mediante la escala analógica visual y la función, con el puntaje de Lysholm. Resultados: Ochenta pacientes cumplían con los criterios de inclusión. Sus datos sociodemográficos fueron pareados en dos grupos similares. Treinta y seis pacientes fueron tratados con la técnica infrarrotuliana y 44, con la técnica suprarrotuliana. Se obtuvieron diferencias estadísticamente significativas en el tiempo de cirugía, el tiempo de radioscopia y en el puntaje de la escala analógica visual para dolor al año. Conclusiones: Los resultados mostraron un menor tiempo de cirugía y de radioscopia, y mejores resultados en la escala analógica visual para dolor con la técnica suprarrotuliana para el tratamiento de las fracturas mediodiafisarias y distales de tibia.

La fascitis necrotizante es una infección potencialmente letal. Es esencial un diagnóstico y tratamiento temprano. Las técnicas de reconstrucción y los protocolos de rehabilitación han sido escasamente descritos. El objetivo de este trabajo es describir los resultados del tratamiento oportuno para la conservación de miembros y la rehabilitación temprana en un caso de fascitis necrotizante masiva de miembros inferiores. Presentamos un caso de fascitis necrotizante en miembros inferiores, tratado quirúrgicamente mediante sistema de aspiración negativa, colgajos musculares e injerto cutáneo. Describimos su protocolo de rehabilitación y los resultados al año de seguimiento.

Building from previous research showing a bilingual advantage in school, the present study investigated the link between bilingualism and academic motivation. We asked whether bilingual students would exhibit higher levels of intrinsic or extrinsic motivation than their monolingual peers, how intrinsic and extrinsic motivation would change over time, and the extent to which those forms of motivation would be in tension with one another. Relative to their monolingual peers, we expected bilingual students to (1) report higher levels of both intrinsic and extrinsic forms of motivation, and (2) show a weaker negative correlation between intrinsic and extrinsic forms of motivation. Bilingual status, intrinsic motivation, and extrinsic motivation were measured at two time points in a diverse sample of 1047 3rd-grade through 8th-grade students (851 monolingual, 196 bilingual). Bilingual students reported significantly higher levels of both intrinsic and extrinsic motivation than monolingual students. They also showed a sharper decline in intrinsic motivation from fall to spring. Intrinsic and extrinsic forms of motivation were negatively correlated for monolinguals, but unrelated for bilinguals, suggesting that the two motive types may be less antagonistic among students who speak a language other than English at home. These differences may be driven by both cognitive (e.g., executive functioning skills) and cultural (e.g., family cohesion, interdependent orientation) factors, and may inform educators who wish to support learning for students from diverse groups.

The tempo and mode of Homo sapiens dispersal in Eurasia and the demise of Neanderthals has sparked debate about the dynamics of Neanderthal extinction and its relationship to the arrival of H. sapiens. In Italy, the so-called ‘Transition’ from Neanderthals to H. sapiens is related to the Uluzzian technocomplex, i.e. the first archaeological evidence for modern human dispersal on the European continent. This paper illustrates the new chronology and stratigraphy of Uluzzo C, a rock shelter and Uluzzian key site located in the Uluzzo Bay in southern Italy, where excavations are ongoing, refining the cultural sequence known from previous excavations. Microstratigraphic investigation suggests that most of the deposit formed after dismantling of the vault of the rock shelter and due to wind input of loess deflated by the continental shelf. The occasional reactivation of the hydrology of the local karst system under more humid conditions further contributed to the formation of specific layers accumulating former Terra Rossa-type soil fragments. Superposed on sedimentary processes, strong bioturbation and the mobilization and recrystallization of calcite have been detected. Optically stimulated luminescence (OSL) ages from Uluzzo C Rock Shelter are congruent with previously published radiocarbon ages obtained on shell beads and tephrachronology from adjacent sites preserving the Uluzzian technocomplex such as Grotta del Cavallo, confirming the onset for the Uluzzian in the area to ca. 39.2–42.0 ka. The OSL chronology from Uluzzo C also provides a terminus post quem for the end of the Mousterian in the region, constraining the disappearance of the Neanderthals in that part of Italy to ≥46 ± 4 ka.

Mild cognitive impairment (MCI) is a state of declining cognitive abilities with conserved everyday functioning. MCI has been linked with increased risk of dementia. Several non-pharmacological interventions have been investigated in this population. Computerised cognitive training (CCT) is a cognition-oriented treatment aimed at improving cognition. Most of the research on CCT has focused on the immediate or short-term effects on cognition and function of people with MCI. Thus, the aim of this review is to synthesise the current evidence on the medium- and long-term effects of CCT on people with MCI.Furthermore, this will be the first meta-analysis to be conducted with www.cogtale.com, an online repository of cognition-oriented treatment studies that automatises several steps of the evidence synthesis process.

Because of the close relationship among soils features and their forming factors, soils and paleosols are a useful archive both to reconstruct past environmental conditions and to gather information on the morphodynamic processes affecting landscape evolution through time. The formation of complex paleosols sequences is deeply affected by the combined effect of different soil forming factors that, shaping pedogenesis, leave marks that can be interpreted and used to reconstruct the climatic and environmental history of the landscape.By integrating geopedological, geomorphological and geoarchaeological data gathered in over 20 years of research, we aimed to reconstruct the environmental Holocene history of the Mt. Cusna area (Northern Italian Apennines). We collected chemical, physical and micromorphological data of about 70 soil profiles into a georeferenced database, which maps different soil characteristics from both modern soils and paleosols. The integration of soil data with other types of available data, as geomorphological map, previous paleoenvironmental and geoarcheological reconstructions, allowed to highlight natural and anthropogenic trends and model the dynamics of past climate history, past environmental conditions, and the reciprocal distribution of landforms and paleosurfaces.We have defined the occurrence of different phases of biostasy, characterized by the absence of erosion and/or deposition on the slope, the presence of vegetation cover, and the soil development, alternated with phases of rhexistasy, characterized by slope instability and soil erosion and burial. The soil and paleosols variability across the study area mirrors the different impact of soil forming factors on pedogenesis (e.g., vegetation cover, human impact, slope dynamics), supporting a detailed characterization of the succession of different environments conditions through space and time.These results highlight how soils can represent an important archive for paleoenvironmental information as well as geomorphological dynamics and demonstrate that a multi-disciplinary approach is necessary to properly characterize soils and retrace environmental changes.

In the context of the development of HALO3D (High Altitude Low Orbit 3D), an edge-based Finite Element Method multidisciplinary solver for hypersonic flows, this paper presents the simulation of fl...

Chemical characterization of cryptotephra is critical for temporally linking archaeological sites. Here, we describe cryptotephra investigations of two Middle–Upper Paleolithic sites from north‐west Italy, Arma Veirana and Riparo Bombrini. Cryptotephra are present as small (75 wt.%) with low FeO ( 1 and P2 is also a high silica rhyolite (>75 wt.%) but with higher FeO (2.33–2.65 wt.%). Shards at Riparo Bombrini (P3) are of the same composition as P1 shards at Arma Veirana, providing a distinct link between deposits at both sites. Geochemical characteristics suggest three possible sources for P1 and P3: eruptions from Lipari Island (56–37.7 ka) in Italy, the Acigöl volcanic field (200–20 ka) in Turkey and the Miocene Kirka‐Phrigian caldera (18 Ma) in Turkey. Eruptions from Lipari Island are the most likely source for P1,3 cryptotephra. This study highlights how cryptotephra can benefit archaeology, by providing a direct link between Arma Veirana and Riparo Bombrini as well as other deposits throughout the Mediterranean.

The interaction of human dispersal patterns with landscape features can in many cases provide useful information on the sustenance strategies of past communities. Mapping the present landscape is a necessary step in recognizing the nature, impact, and diffusion of the processes which drive the behaviour of past populations and modify palaeolandscapes. We constructed a map of the land units in the southwestern corner of Sardinia and compared them with the distribution of known Bronze Age megalithic towers called nuraghes. The vast majority of nuraghes are near the plains or at mid elevations close to the river network, in areas with the highest landscape diversity. The occurrence of nuraghes also seems to be related to elevated outcrops giving the advantage of a raised position and stable foundations. Denudation processes, Late Holocene sea level rise, and anthropogenic disturbance seem to be the most important factors driving changes in the palaeolandscape.

Unmanned aerial vehicles (UAV) are a suitable solution for monitoring growing cultures due to the possibility of covering a large area and the necessity of periodic monitoring. In inspection and monitoring tasks, the UAV must find an optimal or near-optimal collision-free route given initial and target positions. In this sense, path-planning strategies are crucial, especially online path planning that can represent the robot’s operational environment or for control purposes. Therefore, this paper proposes an online adaptive path-planning solution based on the fusion of rapidly exploring random trees (RRT) and deep reinforcement learning (DRL) algorithms applied to the generation and control of the UAV autonomous trajectory during an olive-growing fly traps inspection task. The main objective of this proposal is to provide a reliable route for the UAV to reach the inspection points in the tree space to capture an image of the trap autonomously, avoiding possible obstacles present in the environment. The proposed framework was tested in a simulated environment using Gazebo and ROS. The results showed that the proposed solution accomplished the trial for environments up to 300 m3 and with 10 dynamic objects. The authors would like to thank the following Brazilian Agencies CEFET-RJ, CAPES, CNPq, and FAPERJ. The authors also want to thank the Research Centre in Digitalization and Intelligent Robotics (CeDRI), Instituto Politécnico de Bragança–IPB (UIDB/05757/2020 and UIDP/05757/2020), the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI, and Laboratório Associado para a Sustentabilidade e Tecnologia em Regiões de Montanha (SusTEC) and IPB, Portugal. This work was carried out under the Project “OleaChain: Competências para a sustentabilidade e inovação da cadeia de valor do olival tradicional no Norte Interior de Portugal” (NORTE-06-3559-FSE-000188), an operation to hire highly qualified human resources, funded by NORTE 2020 through the European Social Fund (ESF). info:eu-repo/semantics/publishedVersion

The paper presents an edge-based finite element method formulation for the coupled magnetohydrodynamic equations used for the simulation of magnetogasdynamic propulsion systems. The flow is modeled...

This work aims to describe the physical and numerical modeling of a CFD solver for hypersonic flows in thermo-chemical non-equilibrium. This paper is the second of a two-part series that concerns the application of the solver introduced in Part I to adaptive unstructured meshes.,The governing equations are discretized with an edge-based stabilized finite element method (FEM). Chemical non-equilibrium is simulated using a laminar finite-rate kinetics, while a two-temperature model is used to account for thermodynamic non-equilibrium. The equations for total quantities, species and vibrational-electronic energy conservation are loosely coupled to provide flexibility and ease of implementation. To accurately perform simulations on unstructured meshes, the non-equilibrium flow solver is coupled with an edge-based anisotropic mesh optimizer driven by the solution Hessian to carry out mesh refinement, coarsening, edge swapping and node movement.,The paper shows, through comparisons with experimental and other numerical results, how FEM + anisotropic mesh optimization are the natural choice to accurately simulate hypersonic non-equilibrium flows on unstructured meshes. Three-dimensional test cases demonstrate how, for high-speed flows, shocks resolution, and not necessarily boundary layers resolution, is the main driver of solution accuracy at walls. Equally distributing the error among all elements in a suitably defined Riemannian space yields highly anisotropic grids that feature well-resolved shock waves. The resulting high level of accuracy in the computation of the enthalpy jump translates into accurate wall heat flux predictions. At the opposite end, in all cases examined, high-quality but isotropic unstructured meshes gave very poor solutions with severely inadequate heat flux distributions not even featuring expected symmetries. The paper unequivocally demonstrates that unstructured anisotropically adapted meshes are the best, and may be the only, way for accurate and cost-effective hypersonic flow solutions.,Although many hypersonic flow solvers are developed for unstructured meshes, few numerical simulations on unstructured meshes are presented in the literature. This work demonstrates that the proposed approach can be used successfully for hypersonic flows on unstructured meshes.

Necrotizing fasciitis is a life-threatening infection. Early diagnosis and treatment are essential. Reconstruction techniques and rehabilitation protocols have been poorly described. The objective of this work is to describe the results of timely treatment for limb preservation and early rehabilitation in a case of massive necrotizing fasciitis of the lower limbs. We present a case of necrotizing fasciitis in the lower limbs, treated surgically with a negative aspiration system, muscle flaps, and skin graft. We describe his rehabilitation protocol and the results at one year of follow-up.La fascitis necrotizante es una infección potencialmente letal. Es esencial un diagnóstico y tratamiento temprano. Las técnicas de reconstrucción y los protocolos de rehabilitación han sido escasamente descritos. El objetivo de este trabajo es describir los resultados del tratamiento oportuno para la conservación de miembros y la rehabilitación temprana en un caso de fascitis necrotizante masiva de miembros inferiores. Presentamos un caso de fascitis necrotizante en miembros inferiores, tratado quirúrgicamente mediante sistema de aspiración negativa, colgajos musculares e injerto cutáneo. Describimos su protocolo de rehabilitación y los resultados al año de seguimiento.

Located along the Tigris River in the Kurdistan Region of Iraq (KRI), the Mosul Dam reservoir is the second biggest dam of the Near East, and represents an important water storage for local human activities. The Dam was built between 1981 and 1988 north of the village of Eski Mosul; along this part of the Tigris River several archaeological sites were inundated. Analysis of historical images derived from Declassified Corona satellite acquired between December 1967 and August 1968 reveals seasonal changes of the Tigris riverbed, shifting across the hydrological year from meandering to anastomosing. The geomorphological mapping was carried out on the December 1967 and. in August 1968, Corona images were taken, in order to estimate the modification of several fluvial geomorphological elements such as floodplain and point, middle and longitudinal bars. Here, such evidence is compared with Landsat data collected between the 1990ies and today, in order to detect the first phases of filling of the basin and the control of inherited Tigris channel belt over the reservoir. Moreover, we also noticed an influence of the ancient Tigris course on is recent insertion into the lake. Our work permitted to reconstruct the ancient fluvial landscape below the Mosul Dam Lake, and its evolution in response to seasonal variation of the discharge.

The technological advances in Unmanned Aerial Vehicles (UAV) related to energy power structure inspection are gaining visibility in the past decade, due to the advantages of this technique compared with traditional inspection methods. In the particular case of power pylon structure and components, autonomous UAV inspection architectures are able to increase the efficacy and security of these tasks. This kind of application presents technical challenges that must be faced to build real-world solutions, especially the precise positioning and path following for the UAV during a mission. This paper aims to evaluate a novel architecture applied to a power line pylon inspection process, based on the machine learning techniques to process and identify the signal obtained from a UAV-embedded planar Light Detection and Ranging - LiDAR sensor. A simulated environment built on the GAZEBO software presents a first evaluation of the architecture. The results show an positive detection accuracy level superior to 97% using the vertical scan data and 70% using the horizontal scan data. This accuracy level indicates that the proposed architecture is proper for the development of positioning algorithms based on the LiDAR scan data of a power pylon. This work has been supported by FCT - Fundação para a Ciência e Tecnologia within the Project Scope: UIDB/05757/2020. This work has also been supported by Fundação Araucária (grant 34/2019), and by CAPES and UTFPR through stundent scholarships. info:eu-repo/semantics/publishedVersion

Hypertension affects more than one billion people worldwide. There has been much discussion about clinical practice guidelines (CPGs) following the proposal of lower thresholds for starting pharmacological treatment. Some smaller groups or institutions could benefit from adapting CPGs to their local context, a process that requires high-quality CPGs with few points of conflict in their recommendations. To address this issue, we have compared high-quality hypertension CPGs and highlighted conflicting recommendations.CPGs were searched in MEDLINE, Embase, the Cochrane Library, as well as specific websites. Only CPGs published between 2016 and 2019 were included. We defined CPGs as high-quality if the 'rigor of development' and 'editorial independence' AGREE II domains were scored at least 60%. We compared recommendations made by high-quality CPGs and highlighted areas of conflict (defined as disagreements between more than two CPGs).Nineteen CPGs were identified. The highest scoring domain was 'scope and purpose' (74.3%) and the lowest scoring was 'applicability' (40.0%). Eight CPGs were rated as high quality. Most CPG recommendations on the management of hypertension were consistent. Conflicting recommendations were regarding blood pressure (BP) levels to initiate pharmacotherapy and therapeutic goals, particularly in patients with low cardiovascular risk and older patients.It is possible to adapt hypertension CPGs once high-quality documents have been identified with agreement between most recommendations. Guideline developers can focus on the adaption process and concentrate efforts on implementation.

The abundant faunal remains from the Takarkori rock shelter in the Tadrart Acacus region of southwestern Libya are described. The material that covers the period between 10,200 to 4650 years cal BP illustrates the more humid environmental conditions in the Central Sahara during early and middle Holocene times. Particular attention is focussed on the aquatic fauna that shows marked diachronic changes related to increasing aridification. This is reflected in the decreasing amount of fish remains compared to mammals and, within the fish fauna, by changes through time in the proportion of the species and by a reduction of fish size. The aquatic fauna can, in addition, be used to formulate hypotheses about the former palaeohydrographical network. This is done by considering the possible location of pre-Holocene relic populations combined with observations on the topography and palaeohydrological settings of the Central Sahara. ispartof: Plos One vol:15 issue:2 ispartof: location:United States status: published

Objective Hypertension affects more than one billion people worldwide. There has been much discussion about clinical practice guidelines (CPGs) following the proposal of lower thresholds for starting pharmacological treatment. Some smaller groups or institutions could benefit from adapting CPGs to their local context, a process that requires high-quality CPGs with few points of conflict in their recommendations. To address this issue, we have compared high-quality hypertension CPGs and highlighted conflicting recommendations. Methods CPGs were searched in MEDLINE, Embase, the Cochrane Library, as well as specific websites. Only CPGs published between 2016 and 2019 were included. We defined CPGs as high-quality if the 'rigor of development' and 'editorial independence' AGREE II domains were scored at least 60%. We compared recommendations made by high-quality CPGs and highlighted areas of conflict (defined as disagreements between more than two CPGs). Results Nineteen CPGs were identified. The highest scoring domain was 'scope and purpose' (74.3%) and the lowest scoring was 'applicability' (40.0%). Eight CPGs were rated as high quality. Most CPG recommendations on the management of hypertension were consistent. Conflicting recommendations were regarding blood pressure (BP) levels to initiate pharmacotherapy and therapeutic goals, particularly in patients with low cardiovascular risk and older patients. Conclusion It is possible to adapt hypertension CPGs once high-quality documents have been identified with agreement between most recommendations. Guideline developers can focus on the adaption process and concentrate efforts on implementation.

The paper presents an edge-based finite element method for the simulation of three-dimensional hypersonic flows subject to an imposed magnetic field. Under the magnetogasdynamics assumptions and at...

The numerical modeling of the aerodynamic interactions at high-Altitudes and high-Mach numbers is considered in view of its importance when studying problems where the continuum hypothesis at the foundation of the Navier- Stokes equations becomes invalid. One of the difficulties associated with these flight conditions is that both the velocity and the temperature of the fluid do not abide by the no-slip conditions at the wall. A weak Galerkin finite element formulation of the Maxwell-Smoluchowki model is introduced to discretize the velocity slip and temperature jump conditions with better accuracy than the standard finite element approximation. The methodology is assessed on configurations such as cylinders and spheres for flow conditions ranging from quasi-equilibrium to nonequilibrium. Improvements are observed in the slip regime compared with available data. Nonetheless, the results in the transition regime highlight the need for more sophisticated physical modeling to address nonequilibrium at the wall.

This research is done to know effects of financial performance toward corporate value by using the disclosure of Good Corporate Governance and Corporate Social Responsibility as a moderating variable. ROA, ROE, and Leverage as an indicator of financial performance is known as the independent variable. Company value measured by Tobin’s is known as the dependent variable. Good Corporate Governance(GCG) and Corporate Social Responsibility (CSR) is moderating variable.The companies that are in this research are manufacturing companies which are listed in the Indonesia Stock Exchange (IDX) starting from 2004 until 2007, published financial statements ending 31 December, and had complete data of Good Corporate Governance and Corporate Social Responsibility. The data is then processed by using statistical appliance that are called regression with interaction.According to the research, the financial performance (ROA and leverage) has an effect on corporate value. Disclosure of Corporate Social Responsibility(CSR) does not affect to financial performance (ROA and Leverage) toward the value of the company. Disclosure of Good Corporate Governance (GCG) affects the financial performance of relationship (ROA and Leverage) toward the value of the company.

A parallel formulation of a Jacobian-free all Mach numbers solver on unstructured hybrid meshes is proposed. The Finite Element formulation is edge-based with flow stabilization obtained with either AUSM+ -up or Roe scheme. The linear system is solved via a Jacobian-Free Newton-Krylov (JFNK) method with Lower-Upper Symmetric GaussSeidel (LU-SGS) used as matrix-free preconditioner. The traditional formulation of LU-SGS is enriched by including the contributions from viscous fluxes and boundary conditions. The accuracy and efficiency of the proposed approach are demonstrated over cases ranging from low to high Mach numbers: subsonic flow over the Trap Wing, transonic flow over the ONERA M6 wing, supersonic flow over a sphere, supersonic flow over a waverider and finally hypersonic flow over a sphere.

Hypersonic flows have recently re-acquired an important role in fluids research, with many nations interested in their applications. Due to their complex multidisciplinary aspects, the limitations ...

A mesoscale model for droplet dynamics based on a quasi-molecular approach is proposed. It considers the interaction between quasi-molecules within a single liquid droplet, each quasi-molecule representing an agglomeration of a large number of actual water molecules. The goal is to improve the understanding of the dynamics of large droplet collisions over dry or wet surfaces at velocities typical of aeronautical applications. This detailed analysis will eventually be used to refine the macroscopic Eulerian description of the water impingement process by providing numerical correlations for splashing and bouncing phenomena relevant for in-flight icing applications. Based on the Equipartition Theorem, approaches for extracting macroscopic quantities such as temperature and transport coefficients from the quasi-molecular method are discussed. A proper choice of the free parameters of the model that leads to accurate values of the macroscopic properties is also addressed.

A parallel finite element solver is developed for hypersonic flows with frozen chemistry. The finite element formulation is edge-based with flow stabilization via a Roe scheme. The flow solver is loosely-coupled with a two-temperature thermal non-equilibrium solver. Numerical experiments are performed to assess the accuracy and efficiency of the proposed approach.

A stabilized finite element formulation of the level set equation is proposed for the numerical simulation of water droplet dynamics for in-flight ice accretion problems. The variational multi-scale and Taylor–Galerkin approaches are coupled such that the temporal derivative in the weak Galerkin formulation is replaced with a Taylor series expansion improving the temporal accuracy of the scheme. The variational multi-scale approach is then applied to the semi-discrete equation, allowing the stabilization terms to appear naturally. Taylor series expansions up to the fourth order have been studied in terms of accuracy and convergence rates. A second order implicit expansion was found to provide a good trade-off between accuracy and computational cost when compared to a fourth order implicit expansion. Validation is done through a number of benchmark cases considering droplet stretching and high-speed advection. Results indicate good mass conservation characteristics compared to other methods available in the literature.

A conservative Eulerian numerical approach for modeling postimpact Supercooled Large Droplets undergoing splashing and bouncing on aircraft surfaces is presented. The approach introduces the effect of the postimpact droplets by successive solutions of the conservation equations. Two models have been selected to identify the droplet splashing and bouncing conditions, and to provide initial conditions for the reinjected water. The method has been applied to droplet impingement in Supercooled Large Droplet conditions on clean and iced NACA 23012 geometries, as well as the MS(1)-0317 airfoil, and the results have been compared to experimental data. Good agreement is observed for both impingement limits and collection efficiency. Additionally, the method has been applied to a three-element high-lift configuration operating in one of the proposed Appendix O Supercooled Large Droplet environments to demonstrate the danger posed by the re-impingement of splashing and bouncing droplets on complex interacting aerod...

DOI: 10.2514/1.C031607 This paper presents a truly unsteady approach for the numerical simulation of in-flight electrothermal anti-icing orde-icing, using a conjugate heat transfer technique. This numerical approach has been implemented in FENSAPICE to compute the complex heat transfer phenomena occurring during in-flight de-icing with multiple heating elements following independent cycling. At each time step, the energy fluxes through the aircraft’s solid skin, the melting ice layer, the liquid water film, and the external fluid are computed. The ice shape is then modified by taking intoaccounttheopposingmassbalanceeffectsoficeaccretingduetotheimpactofsupercooleddropletsand/orwater runback, and the partial or total melting of the existing ice layer due to heating. The results of the verification of this phase-changeconductioncodearepresented,followedbyastudyofintercyclede-icingonawing,showingintercycle ice growth. Nomenclature ch = convective heat flux coefficient d = droplet diameter E = internal energy e = volumetric internal energy H = enthalpy

A IRCRAFT flying through clouds of supercooled liquid droplets (SLD) can be subjected to in-flight ice accretion. Surface tension prevents the expansion of the droplets that would occur with phase change, forcing them to remain in liquid form even though their temperature is below the freezing point. When the droplets hit an aircraft’s surfaces, the surface tension decreases at the contact point, and theymay freeze completely on impact if the temperature is very low or freeze partially at higher temperatures, whereas the remaining liquid portion runs back on the surface, transported by the pressure gradient and the shear stress of the airflow. If no ice protection is provided, the aerodynamic characteristics of the aircraft and its handling can be severely degraded when ice accretes. The increased drag generated by the roughness of the ice can lead to flow separation, reduction of the stall margins, control reversals, and engine blockages [1]. Airworthiness of transport airplanes in icing conditions is demonstrated by compliance with certification standards (Appendix C of the FAA Federal Aviation Regulations, part 25) set by agencies, such as the Federal Aviation Administration, European Air Safety Association, Transport Canada, etc. These standards, frozen for 50 years, will soon undergo significant revisions with the adoption of Appendix O to address the icing threat posed by SLD conditions. Unlike smaller droplets, SLD can distort, break into smaller droplets, splash, bounce off surfaces, get carried downstream by the flow, and reimpinge, increasing the potential for ice contamination on unprotected surfaces [2–4]. Nowadays, wind tunnel tests, icing tunnel tests, and computer simulations play major complementary roles in the process of certifying a new aircraft [5,6]. Advances in modeling capabilities have created the conditions to accurately simulate the ice accretion process in a realistic three-dimensional (3-D) context [7,8]. Unfortunately, the computational cost associated with performing a multitude of 3-D simulations of various aeroicing conditions somewhat limits the widespread use of computational fluid dynamics (CFD), even if advanced computational resources are available [9,10]. To overcome this difficulty, mostly low-cost and, consequently, low-fidelity tools are usually employed. These may be based on empirical correlations, two-dimensional (2-D) approximations, inviscid or incompressible flow assumptions, and/or other simplifications that result in limited accuracy and realism. A viable alternative is the reduced-order modeling (ROM) approach [11,12], which dramatically reduces the cost of highfidelity simulations while providing solutions of superior accuracy to low-fidelity methods because it preserves the detailed physical modeling of the problem under consideration [13–16]. Although the use of this approach in the aeroicing environment is in its pioneering phase, recent results support the effectiveness of this methodology as a valuable tool in the context of a multicondition, multiparameter certification process [17–20]. In a framework of ice accretion simulation as the succession of airflow, water concentration, and heat transfer calculations, the most time-consuming part is obtaining the water impact patterns. The common practice is to assume a distribution of discrete droplet diameters, compute the impingement distribution of each diameter class, andweight-average thesemonodispersed solutions. In the case of the droplet sizes of Appendix C, seven distinct monodispersed sizes (Langmuir-D distribution) are used to compute the overall impingement distribution. In the SLD regime, however, due to the complex phenomena of droplet breakup, splashing, and bouncing, distributions containing up to 27 diameters of monodispersed droplets are needed to obtain realistic impingement predictions [5–7]. The computational cost of an SLD simulation is hence four times that of a Langmuir-D distribution. In the presentwork, it will be shown that the ROM approach can dramatically reduce cost with only a very modest degradation of the overall accuracy of the simulation. The essentials of the ROM approach used to extract the solution eigenfunctions (or modes) and compute solutions at unknown states are introduced in sections II and III of this paper, whereas section IV illustrates the interpolation technique used to compute the surrogate solutions. Finally, 2and 3-D results and comparison with experiments and other methods are presented to validate the present methodology. Received 29 July 2011; revision received 14 September 2011; accepted for publication 15 September 2011. Copyright © 2011 by Wagdi Habashi. Published by the American Institute of Aeronautics and Astronautics, Inc., with permission. Copies of this paper may be made for personal or internal use, on condition that the copier pay the $10.00 per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923; include the code 0021-8669/12 and $10.00 in correspondence with the CCC. Postdoctoral Research Associate, Mechanical Engineering, Computational Fluid Dynamics Laboratory, 688 Sherbrooke Street West; mfossati@cfdlab.mcgill.ca. Member AIAA (Corresponding Author). Professor and Director, NSERC-J. Armand Bombardier-Bell HelicopterCAE Industrial Research Chair of Multidisciplinary Computational Fluid Dynamics Laboratory, Department of Mechanical Engineering, 688 Sherbrooke Street West, Fellow AIAA. Research &Development Director, 688 Sherbrooke StreetWest, Member AIAA. JOURNAL OF AIRCRAFT Vol. 49, No. 2, March–April 2012

In-flight ice accretion, even though driven by a steady flow airstream, is an inherently unsteady phenomenon. It is, however, completely ignored in icing simulation codes (one-shot) or, at best approximated via quasi-steady modeling (multishot). The final ice shapes thus depend on the length of the total accretion time (one-shot), or of the arbitrarily prescribed time intervals (multishot), during which the impact of ice growth on both airflow and water impingement is ignored. Such a longstanding heuristic approximation is removed in this paper by coupling in time the dilute two-phase flow (air and water droplets flow) with ice accretion, and is implemented in a new code, FENSAP-ICE-Unsteady. The two-phase flow is solved using the coupled Navier–Stokes and water concentration equations, and the water film characteristics and ice shapes are obtained from laws of conservation of mass and energy within the thin film layer. To continually update the geometry of the iced surface in time, arbitrary Lagrangian–Eulerian terms are added to all governing equations to account for mesh movement in the case of stationary components. In the case of rotating/stationary interacting components, a dynamically stitched grid is used. The numerical results clearly show that unsteady modeling improves the accuracy of both rime and glaze ice shape prediction, compared with the traditional quasi-steady approach with frozen solutions. The unsteady model is shown to open the door for a unified approach to icing on fixed wings, on helicopters with blades/rotors/fuselage systems. Problems of current concern in the icing community such as the ingestion of ice crystals at high altitude become tractable with the new formulation.

The present paper is the second article in a three-part series on anisotropic mesh adaptation and its application to (2-D) structured and unstructured meshes. In the first article, the theory was presented, the methodology detailed and brief examples given of the application of the method to both types of grids. The second part details the application of the mesh adaptation method to structured grids. The adaptation operations are restricted to mesh movement in order to avoid the creation of hanging nodes. Being based on a spring analogy with no restrictive orthogonality constraint, a wide grid motion is allowed. The adaptation process is first validated on analytical test cases and its high efficiency is shown on relevant transonic and supersonic benchmarks. These latter test cases are also solved on adapted unstructured grids to provide a reference for comparison studies. The third part of the series will demonstrate the capability of the methodology on 2-D unstructured test cases. Copyright © 2002 John Wiley & Sons, Ltd.