Equações de Painlevé mistas e modelo PIII-PV simétrico

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Solving the multiobjective environmental/economic dispatch problem using weighted sum and ε-constraint strategies and a predictor-corrector primal-dual interior point method

This paper proposes a technique for solving the multiobjective environmental/economic dispatch problem using the weighted sum and ε-constraint strategies, which transform the problem into a set of single-objective problems. In the first strategy, the objective function is a weighted sum of the environmental and economic objective functions. The second strategy considers one of the objective functions: in this case, the environmental function, as a problem constraint, bounded above by a constant. A specific predictor-corrector primal-dual interior point method which uses the modified log barrier is proposed for solving the set of single-objective problems generated by such strategies. The purpose of the modified barrier approach is to solve the problem with relaxation of its original feasible region, enabling the method to be initialized with unfeasible points. The tests involving the proposed solution technique indicate i) the efficiency of the proposed method with respect to the initialization with unfeasible points, and ii) its ability to find a set of efficient solutions for the multiobjective environmental/economic dispatch problem.

Model reduction techniques in flexible multibody dynamics with application to engine cranktrain simulation

The development of a multibody model of a motorbike engine cranktrain is presented in this work, with an emphasis on flexible component model reduction. A modelling methodology based upon the adoption of non-ideal joints at interface locations, and the inclusion of component flexibility, is developed: both are necessary tasks if one wants to capture dynamic effects which arise in lightweight, high-speed applications. With regard to the first topic, both a ball bearing model and a journal bearing model are implemented, in order to properly capture the dynamic effects of the main connections in the system: angular contact ball bearings are modelled according to a five-DOF nonlinear scheme in order to grasp the crankshaft main bearings behaviour, while an impedance-based hydrodynamic bearing model is implemented providing an enhanced operation prediction at the conrod big end locations. Concerning the second matter, flexible models of the crankshaft and the connecting rod are produced. The well-established Craig-Bampton reduction technique is adopted as a general framework to obtain reduced model representations which are suitable for the subsequent multibody analyses. A particular component mode selection procedure is implemented, based on the concept of Effective Interface Mass, allowing an assessment of the accuracy of the reduced models prior to the nonlinear simulation phase. In addition, a procedure to alleviate the effects of modal truncation, based on the Modal Truncation Augmentation approach, is developed. In order to assess the performances of the proposed modal reduction schemes, numerical tests are performed onto the crankshaft and the conrod models in both frequency and modal domains. A multibody model of the cranktrain is eventually assembled and simulated using a commercial software. Numerical results are presented, demonstrating the effectiveness of the implemented flexible model reduction techniques. The advantages over the conventional frequency-based truncation approach are discussed.

Anterior approaches to the acetabulum

Since the 1960s the ilioinguinal approach by Letournel with the three anatomic windows has been successfully established for the treatment of acetabular fractures involving predominantly the anterior column. The previous standard approach, the iliofemoral approach by Smith-Petersen, is still used for the therapy of anterior wall or isolated femoral head fractures. The increase in acetabular fractures in the elderly with lateral compression fractures after lateral falls, characterized by medial displacement of the quadrilateral plate and superomedial dome impaction, led to the use of the intrapelvic modified Stoppa approach with or without the first window of the ilioinguinal approach in the 1990s. To combine the advantages of the second and third windows of the ilioinguinal approach and the medial view of the modified Stoppa approach the Berne research group recently introduced the pararectus approach in acetabular surgery, which can be used as a less invasive acetabular surgical (LIAS) technique especially in the elderly.

Cardiovascular-renal axis disorders in the domestic dog and cat: a veterinary consensus statement.

OBJECTIVES There is a growing understanding of the complexity of interplay between renal and cardiovascular systems in both health and disease. The medical profession has adopted the term "cardiorenal syndrome" (CRS) to describe the pathophysiological relationship between the kidney and heart in disease. CRS has yet to be formally defined and described by the veterinary profession and its existence and importance in dogs and cats warrant investigation. The CRS Consensus Group, comprising nine veterinary cardiologists and seven nephrologists from Europe and North America, sought to achieve consensus around the definition, pathophysiology, diagnosis and management of dogs and cats with "cardiovascular-renal disorders" (CvRD). To this end, the Delphi formal methodology for defining/building consensus and defining guidelines was utilised. METHODS Following a literature review, 13 candidate statements regarding CvRD in dogs and cats were tested for consensus, using a modified Delphi method. As a new area of interest, well-designed studies, specific to CRS/CvRD, are lacking, particularly in dogs and cats. Hence, while scientific justification of all the recommendations was sought and used when available, recommendations were largely reliant on theory, expert opinion, small clinical studies and extrapolation from data derived from other species. RESULTS Of the 13 statements, 11 achieved consensus and 2 did not. The modified Delphi approach worked well to achieve consensus in an objective manner and to develop initial guidelines for CvRD. DISCUSSION The resultant manuscript describes consensus statements for the definition, classification, diagnosis and management strategies for veterinary patients with CvRD, with an emphasis on the pathological interplay between the two organ systems. By formulating consensus statements regarding CvRD in veterinary medicine, the authors hope to stimulate interest in and advancement of the understanding and management of CvRD in dogs and cats. The use of a formalised method for consensus and guideline development should be considered for other topics in veterinary medicine.

Periazetabuläre Frakturen bei Hüftprothesen

Periazetabuläre Frakturen bei Hüftprothesen nehmen aufgrund der Überalterung und der zunehmenden Aktivität alter Menschen zu. Die periprothetischen Azetabulumfrakturen werden anhand der Einteilung von Letournel klassifiziert. Wenn beide Azetabulumpfeiler bei Hüftprothese betroffen sind, wird auch von einer Beckendiskontinuität gesprochen. Durch eine laterale Kompression können auch periazetabuläre Schambeinastfrakturen und/oder transiliakale Frakturen auftreten. Für die Therapieentscheidung (konservativ, alleinige Osteosynthese, Revisionshüfttotalprothese mit oder ohne zusätzliche Osteosynthese des Vorder- und/oder Hinterpfeilers) und die Zugangswahl bei operativer Versorgung werden patientenspezifische (Alter, Morbidität, Osteoporose, Aktivitätslevel des Patienten), frakturspezifische (Frakturtyp, Dislokationsausmaß, Impression des Doms oder der Hinterwand) und auch prothesenspezifische Faktoren (Art der implantierten Prothese [Hemiprothese vs. Totalprothese], Pfannenstabilität, Zeichen eines Prothesenabriebs, Ausmaß und Lokalisation einer azetabulären Lyse, Stabilität und Lysezeichen des Prothesenschafts) berücksichtigt. Bei akuten Beckendiskontinuitäten werden neben einer Osteosynthese des dorsalen Pfeilers zunehmend eine schnell ossär integrierbare Pfanne (Tantalum [„Trabecular Metal“: TM]) mit oder ohne Augment und/oder Allograft und allenfalls in einer sog. „Cup-Cage“-Technik (TM-Pfanne mit einem abstützenden Revisionsring [Burch-Schneider-Ring] analog zur Therapie von chronischen Beckendiskontinuitäten empfohlen. Bei großen Lysezonen und starken Dislokationen des vorderen Pfeilers und der quadrilateralen Fläche können intrapelvine Zugänge (modifizierter Stoppa- oder Pararectus-Zugang nach Keel) zur zusätzlichen Zuggurtungsosteosynthese des vorderen Pfeilers und Abstützung der quadrilateralen Fläche gewählt werden.

THE KYOTO PROTOCOL AND THE WTO: INSTITUTIONAL EVOLUTION AND ADAPTATION. CEPS Policy Brief No. 28/December

Overview. Questions about the interface between the multilateral climate regime embodied in the Kyoto Protocol and the multilateral trade regime embodied in the World Trade Organisation (WTO) have become especially timely since the fall of 2001. At that time, ministerial-level meetings in Marrakech and Doha agreed to advance the agendas, respectively, for the implementation of the Kyoto Protocol and for negotiations on further agreements at the WTO. There have been concerns that each of these multilateral arrangements could constrain the effectiveness of the other, and these concerns will become more salient with the entry into force of the Kyoto Protocol. There are questions about whether and how the rights and obligations of the members of the WTO and the parties to the Protocol may conflict. Of particular concern is whether provisions in the Protocol, as well as government policies and business activities undertaken in keeping with those provisions, may conflict with the WTO non-discrimination principles of national treatment and most-favoured nation treatment. The WTO agreements that are potentially relevant to climate change issues include many of the individual Uruguay Round agreements and subsequent agreements as well. The principal elements of the Kyoto Protocol that are particularly relevant are its provisions concerning emissions trading, the Clean Development Mechanism, Joint Implementation, enforcement, and parties’ policies and measures. In combination, therefore, there are numerous potential points of intersection between the elements of the Kyoto Protocol and the WTO agreements. Previous studies have clarified many issues, as they have focused on particular aspects of the regimes’ relationships. Yet, some analyses suggest that the two regimes are largely compatible and even mutually reinforcing, while others suggest that there are significant conflicts between them. Those and other studies are referenced in the ‘suggestions for further reading’ section at the end of the paper.1 The present paper seeks to expand on those studies by providing additional breadth and depth to understanding of the issues. The analysis gives special attention to key issues on the agenda – i.e. issues that are particularly problematic because of the likelihood of occurrence of specific conflicts and the significance of their economic and/or political consequences. The paper adopts a modified ‘triage’ approach, which classifies points of intersection as (a) highly problematic and clearly in need of further attention, (b) perhaps problematic but less urgent, and (c) apparently not problematic, at least at this point in time. The principal conclusions are that: · The missions and objectives of the two regimes are largely compatible, and their operations are potentially mutually reinforcing in several respects. · Some provisions of the multilateral agreements that may superficially seem at odds are not likely to become particularly problematic in practice. · ‘Domestic policies and measures’ that governments may undertake in the context of the Protocol could pose difficult issues in the context of WTO dispute cases. · Recent WTO agreements and dispute cases acknowledge the legitimacy of the ‘precautionary principle’ and are thus consistent with the environmental protection objectives of the Protocol. · The relative newness of the climate regime creates opportunities for institutional adaptation, as compared with the constraints of tradition in the trade-investment regime. · The prospect of largely independent evolutionary paths for the two regimes poses a series of issues about future international regime design and management, which may require new institutional arrangements. In sum, the present paper thus finds that although there are some areas of interaction that are problematic, the two regimes may nevertheless co-exist in relative harmony in other respects –more like ‘neighbours’ than either ‘friends’ or ‘foes’, as Krist (2001) has suggested.

Climatic classification: the semi-arid tropics and its environment a review.

This paper analyses the advantages and limitations in using the Troll, Hargreaves and modified Thornthwaite approaches for the demarcation of the semi-arid tropics. Data from India, Africa, Brazil, Australia and Thailand, were used for the comparison of these three methods. The modified Thornthwaite approach provided the most relevant agriculturally oriented demarcation of the semi-arid tropics. This method in not only simple, tut uses input data that are avaliable for a global network of stations. Using this method the semi-arid tropics include major dryland or rainfed agricultural zones with annual rainfall varying from about 400 to 1,250 mm. Major dryland crops are pearl millet, sorghum, pigeonpea and groundnut. This paper also presents the brief description of climate, soils and farming systems of the semi-arid tropics.

Cordectomía por sustracción pedicular en la columna dorsal y lumbar en fracturas traumáticas: experiencia en el hospital universitario mayor Mederi y revisión sistemática de la literatura

Objetivo: Presentar la experiencia con la técnica de corpectomia por sustracción pedicular en fracturas traumática a nivel de la columna dorsal y Lumbar en el Hospital Universitario Mayor en Bogotá y hacer una revisión sistemática de la literatura de esta técnica quirúrgica. Material y métodos: Se realizó un análisis retrospectivo de las historias clínicas de pacientes que consultaron al servicio de neurocirugía entre los años 2013 y 2015 con fracturas traumáticas a nivel de la columna dorsal y lumbosacra. Se realizó un análisis de déficit neurológico pre y posoperatorio por medio de la Clasificación neurológica estándar de lesión medular (ASIA), al igual que tiempos de cirugía, sangrado intraoperatorio y complicaciones. A su vez se realiza una revisión sistemática de la literatura sobre esta técnica quirúrgica. Resultados: El total de pacientes que se sometieron a cirugía fue de 32, de los cuales el tiempo quirúrgico promedio fue de 396 min, se obtuvo un ASIA prequirúrgico B: 50% C: 47% y E: 3%. El ASIA post operatorio fue de B: 9% C: 47% D: 38% E: 6%. Se obtuvo una mejoría del déficit neurológico en el 75% los pacientes intervenidos. El promedio de sangrado fue de 1,223 cc. Se tuvieron 4 complicaciones, 2 hematomas en lecho quirúrgico que requirió re intervención y dos fistulas de líquido cefalorraquídeo las cuales se manejaron con vendaje compresivo y reposo absoluto. Conclusiones: La corpectomia por sustracción pedicular requiere de un adecuado entrenamiento y un grupo multidisciplinario dentro de los que se incluye neuroanestesiologo, a su vez de neurocirujanos entrenados en columna. Este abordaje presenta grandes beneficios como disminución de tiempos quirúrgicos, disminución de sangrado intraoperatorio y disminución de morbilidad entre otras.

Modified lattice model for mode-I fracture analysis of notched plain concrete beam using probabilistic approach

A modified lattice model using finite element method has been developed to study the mode-I fracture analysis of heterogeneous materials like concrete. In this model, the truss members always join at points where aggregates are located which are modeled as plane stress triangular elements. The truss members are given the properties of cement mortar matrix randomly, so as to represent the randomness of strength in concrete. It is widely accepted that the fracture of concrete structures should not be based on strength criterion alone, but should be coupled with energy criterion. Here, by incorporating the strain softening through a parameter ‘α’, the energy concept is introduced. The softening branch of load-displacement curves was successfully obtained. From the sensitivity study, it was observed that the maximum load of a beam is most sensitive to the tensile strength of mortar. It is seen that by varying the values of properties of mortar according to a normal random distribution, better results can be obtained for load-displacement diagram.

Coulomb-hole summations and energies for GW calculations with limited number of empty orbitals: a modified static remainder approach

Ab initio GW calculations are a standard method for computing the spectroscopic properties of many materials. The most computationally expensive part in conventional implementations of the method is the generation and summation over the large number of empty orbitals required to converge the electron self-energy. We propose a scheme to reduce the summation over empty states by the use of a modified static remainder approximation, which is simple to implement and yields accurate self-energies for both bulk and molecular systems requiring a small fraction of the typical number of empty orbitals.

A modified approach to numerical solution of Fredholm integral equations of the second kind

A modified approach to obtain approximate numerical solutions of Fredholin integral equations of the second kind is presented. The error bound is explained by the aid of several illustrative examples. In each example, the approximate solution is compared with the exact solution, wherever possible, and an excellent agreement is observed. In addition, the error bound in each example is compared with the one obtained by the Nystrom method. It is found that the error bound of the present method is smaller than the ones obtained by the Nystrom method. Further, the present method is successfully applied to derive the solution of an integral equation arising in a special Dirichlet problem. (C) 2015 Elsevier Inc. All rights reserved.

Monolithic Integration of Electro-Absorption Modulators and DFB Lasers by Modified Double Stack Active Layer Approach

Monolithic electro-absorption modulated distributed-feedback(DFB) lasers are proposed and fabricated by using a modified double stack active layer.The 38mA threshold,9dB extinction ratio (from 0.5V to 3.0V),and about 5mW output power at the 100mA operation current are achieved.Compared with other reported results (only 1.5mW at the same operation current) of the traditional stack active structure,the proposed structure improves the output power of devices.

On configuration of exchanged La3+ on ZSM-5: A theoretical approach to the improvement in hydrothermal stability of La-modified ZSM-5 zeolite

Density functional calculations have been employed to investigate the locating and binding of lanthanum cation, i.e., La(OH)(2)(+), on HZSM-5 zeolite. Through geometry optimization, it was determined that lanthanum ions are favorably accommodated in the two 6-T rings of the straight channels (Clusters 1 and 2, see Sec. III A for details). Cluster 1 was found to exist in prior to Cluster 2 due to the preference of Al substitution in the T11 site (Cluster 1) rather than in the T8 site (Cluster 2). Geometry-optimization of Cluster 1 containing another two lanthanide ions Nd3+ and Yb3+ was also carried out and it was found that a monotonic decrease in Ln-O bond length will take place as the atomic number increases, conforming well to the rule of lanthanide contraction. Some of the optimized parameters are comparable to the corresponding experimental values in Y zeolite, which confirms that the optimized configurations are acceptable. The average frequencies of hydroxyls attached to La3+ or Yb3+ in Cluster 1 fall at 3609.16 and 3579.76 cm(-1), respectively, with the gap of these two frequencies close to that in the sodalite cage of Y zeolite. Compared to H-form zeolite, the charges on both Al and O atoms in Ln-ZSM-5 zeolite show an obvious increase, which will undoubtedly lead to a stronger mutual interaction and hence enhance the stability of the [AlO4](-) anion. Moreover, the Ln(OH)(2)(+) seem to have thickened the zeolite framework, which can effectively retard the process of dealumination. Through the evaluation of the possibility for dimer formation, it turned out that when the exchange degree arrived to approximately 0.28, lanthanum monomers began to aggregate into dimers, and were completely converted into dimers when the exchange degree approached 0.60. (C) 2003 American Institute of Physics.