263 research outputs found
Not-XOR (NXOR) Logic Gate Realized with Enzyme-Catalyzed Reactions: Optical and Electrochemical Signal Transduction
No full textThe studied enzyme-based biocatalytic system mimics NXOR Boolean logic gate, which is a logical operator that corresponds to equality in Boolean algebra. It gives the functional value true (1) if both functional arguments (input signals) have the same logical value (0,0 or 1,1), and false (0) if they are different (0,1 or 1,0). The output signal producing reaction is catalyzed by pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH), which is inhibited at acidic and basic pH values. Two other reactions catalyzed by esterase and urease produce acetic acid and ammonium hydroxide, respectively, shifting solution pH from the optimum pH for PQQ-GDH to acidic and basic values (1,0 and 0,1 input combinations, respectively), thus switching the enzyme activity off (output 0). When the input signals are not applied (0,0 combination) or both applied compensating each other (1,1 combination) the optimum pH is preserved, thus keeping PQQ-GDH running at the high rate (output 1). The biocatalytic cascade mimicking the NXOR gate was characterized optically and electrochemically. In the electrochemical experiments the PQQ-GDH enzyme communicated electronically with a conducting electrode support, thus resulting in the electrocatalytic current when signal combinations 0,0 and 1,1 were applied. The logic gate operation, when it was realized electrochemically, was also extended to the biomolecular release controlled by the gate. The release system included two electrodes, one performing the NXOR gate and another one activated for the release upon electrochemically stimulated alginate hydrogel dissolution. The studied system represents a general approach to the biocatalytic realization of the NXOR logic gate, which can be included in different catalytic cascades mimicking operation of concatenated gates in sophisticated logic circuitries
Late socialist revolutionary achievements of the township of Filipov: Cahiers du CEFRES N° 30, Le communisme à partir des sociétés - Communism from the viewpoint of societies
No full textInternational audienceFilipov is a township of three thousand, in the border and mostly agricultural county of Dubno, in Eastern Moravia. The author analyses how, though Filipov took a long time to recover from the post-war collapse and the socialist transformation, it gradually became a stable and prosperous municipality in a quiet county where, even as late as 1989, there was almost no indication that some changes in its well established way of life would soon arrive. It seems that when the changes occurred, the people of Filipov successfully passed through the phases of the Revolution (or, more precisely, the transfer of power) in a way that mirrored exactly how changes occurred at the centre. Indeed, it was not until the period 1997 to 1999, when the township was studied, that Filipov was forced to confront a crisis because of overspending on development motivated by the “Construction Spirit”, a legacy from Real Socialism. Kabele therefore asks the question why the people of Filipov completed a “Velvet Revolution” when the town was doing well, and why did it fail
Tailoring stiffness of deployable origami structures
No full textEmbargo set by: Seth Robbins for item 98713
Lift date: 2019-03-01T17:03:32Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemOrigami has gained popularity in science and engineering because a compactly stowed system can be folded into a transformable 3D structure with increased functionality. Origami can also be reconfigured and programmed to change shape, function, and mechanical properties. In this thesis, we explore origami from structural and stiffness perspectives, and in particular we study how geometry affects origami behavior and characteristics. Understanding origami from a structural standpoint can allow for conceptualizing and designing feasible applications in all scales and disciplines of engineering.
We improve, verify, and test a bar and hinge model that can analyze the elastic stiffness, and estimate deformed shapes of origami. The model simulates three distinct behaviors: stretching and shearing of thin sheet panels; bending of the flat panels; and bending along prescribed fold lines. We explore the influence of panel geometry on origami stiffness, and provide a study on fold line stiffness characteristics. The model formulation incorporates material characteristics and provides scalable, and isotopic behavior. It is useful for practical problems such as optimization and parametrization of geometric origami variations.
We explore the stiffness of tubular origami structures based on the Miura-ori folding pattern. A unique orientation for zipper coupling of rigidly foldable origami tubes substantially increases stiffness in higher order modes and permits only one flexible motion through which the structure can deploy. Deployment is permitted by localized bending along folds lines, however other deformations are over-constrained and engage the origami sheets in tension and compression. Furthermore, we couple compatible origami tubes into a variety of cellular assemblages that can enhance mechanical characteristics and geometric versatility. Practical applications such as deployable slabs, roofs, and arches are also explored.
Finally, we introduce origami tubes with polygonal cross-sections that can reconfigure into numerous geometries. The tubular structures satisfy the mathematical definitions for flat and rigid foldability, meaning that they can fully unfold from a flattened state with deformations occurring only at the fold lines. From a global viewpoint, the tubes do not need to be straight, and can be constructed to follow a non-linear curved line when deployed. From a local viewpoint, their cross-sections and kinematics can be reprogrammed by changing the direction of folding at some folds.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2018-12-01The student, Evgueni Filipov, accepted the attached license on 2016-11-30 at 15:41.The student, Evgueni Filipov, submitted this Dissertation for approval on 2016-11-30 at 15:54.This Dissertation was approved for publication on 2016-12-01 at 14:38.DSpace SAF Submission Ingestion Package generated from Vireo submission #10379 on 2017-02-28 at 14:42:29Made available in DSpace on 2017-03-01T17:01:48Z (GMT). No. of bitstreams: 3
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Previous issue date: 2016-12-01Embargo set by: Seth Robbins for item 98713
Lift date: 2019-03-01T17:02:22Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 98713
Lift date: 2019-03-01T17:05:02Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 98713
Lift date: 2019-03-01T17:06:55Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemLimited Restriction Lifted for Item 98713 on 2019-03-02T10:15:33Z
Avaliação da dose fetal em radioterapia de mama, com câmara de ionização cilíndrica, usando blindagem e filtros físico e dinâmico
No full textWhen a pregnant woman is submitted to breast radiotherapy, the fetus may be seriously affected by the peripheral dose. In order to verify that dose, a humanoid phantom, was irradiated at the left breast. The phantom is an adapted manikin, with some materials (densities close to water) inside and outside of it. The irradiation was done using a 6 MeV x-ray beam energy from a linear accelerator “Clinac 600C”. During the irradiation, a shield around the abdominal area of the manikin, consisting of blocks and slabs of lead was used. In addition, two types of filters were used: a physical, with 30o angulation, and an enhanced dynamic one. Through a cylindrical ionization chamber, positioned in the simulator ́s fetal region, it was found that, at the end of the breast treatment, the peripheral doses reach values between 3.90 and 48.67 cGy, when the physical wedge was used. With the application of the enhanced dynamic wedge, the values were between 1.75 and 13.78 cGy. According to the obtained data, the physical wedge can increase the peripheral dose due to the larger background radiation intensity and to the scattering caused by the attenuator material. In addition, the shielding couldn ́t block all the secondary radiation, which, according to the literature, can be able to induce mental retardation and cancer during postnatal life. However, the induction to these effects is negligible, when the type of wedge was changed.Quando uma mulher grávida é submetida à radioterapia mamária, o feto pode ser gravemente afetado pela dose periférica. Com o objetivo de verificar essa dose, um objeto simulador humanóide foi irradiado na mama esquerda. O phantom é um manequim adaptado, com alguns materiais (de densidades próximas a da água) dentro e fora do mesmo. A irradiação foi feita usando feixes de raios X de energia de 6 MeV, provenientes de um acelerador linear “Clinac 600C”. Durante as irradiações, foi empregada uma blindagem, constituída de blocos e placas de chumbo, em torno da região abdominal do manequim. Além disso, foram utilizados dois tipos de filtros: físico, com angulação de 30o, e dinâmico. Através de uma câmara de ionização cilíndrica posicionada na região fetal do simulador, verificou-se que, ao final do tratamento mamário, a dose de radiação periférica atinge valores entre 3,90 e 48,67 cGy quando se irradia com o filtro físico, e entre 1,75 e 13,78 cGy para o filtro dinâmico; ambos com a blindagem. Através dos dados obtidos, conclui-se que a implantação do filtro físico incrementa a dose periférica devido ao aumento da intensidade da radiação de fuga e ao espalhamento causado pelo material atenuador. Além disso, a blindagem empregada não foi suficiente para bloquear toda radiação secundária: Ao se empregar o filtro em cunha, segundo a literatura, as doses podem ser capazes de induzir o retardo mental e o câncer durante a vida pós-nascimento. Já com o filtro dinâmico esses riscos são reduzidos drasticamente, chegando a ser ínfimos
Bulgaria: Asen Filipov Stoyanov
No full textA document from Amnesty International's Urgent Action Networ
not available
No full textSeja M um domínio, dividido em duas partes, N e S, utilizando-se uma função diferenciável f. Seja D a fronteira comum de N e S. Em N é definido um campo vetorial X e em S um campo vetorial Y, formando assim um campo Z definido em M, chamado de campo vetorial descontínuo. Filipov [Fi] desenvolveu as regras para a transição das órbitas entre as regiões N e S ou a permanência das mesmas em D. Sosotmayor e Teixeira [S-T] utilizaram como domínio a esfera 'S. POT 2' e desenvolveram o métododa regularização. Este método consiste em utilizar uma função de transição 'fi' para formar uma família de campos vetoriais contínuos que se aproxima do campo vetorial descontínuo, quando o parâmetro 'epsilon' tende a zero. Estes campo vetoriais contínuos são chamados de campos vetoriais que os campos vetoriais regularizados. Sotomayor e Teixeira estabeleceram condições sobre Z para que os campos vetoriais regularizados sejam estruturalmente estáveis. Neste trabalho utiliza-se comodomínio uma região M compacta e contida em 'R. POT 2'. E, utilizando-se o método da regularização , estabelece-se condições sobre X e Y para os campos regularizados sejam estruturalmente estáveisLet M be a doamin, divided in two parts, N and S, using a differentiable function f. Let D be the common border of N and S. In N is defined a vector field X, and in S a vector field Y, forming thereby a field Z, defined in M, called discontinuous vector field. Filipov [Fi] developed the rules for the transition of the orbits between N and S, or their persistence in D. Sotomayor and Teixeira [S-T] used as domain the sphere 'S.pot.2' and developed the regularization method. This method consists in using a transition function 'fi' to define a one parameter family of continuous vector field. When the parameter goes to zero. These continuous vector fileds are called regularized vector fields. Sotomayor and Teixeira provided conditions over Z, in orderb to the regularized vector fields be structuraly stable. This paper uses as domain a compact M region contained in 'R.pot.2'. Using the regularization method, searches the conditions over X and Y, in order to the regularized vector fields be strucuturaly stabl
Untitled in english
No full textA mineração brasileira de rocha ornamental apresenta, nos últimos anos, um significativo crescimento, principalmente pela exportação de produtos acabados e semi-acabados, que permitiram agregar valor ao material. O mercado brasileiro se destaca por seu grande dinamismo e diversificação, em virtude da enorme variedade e das tendências estéticas da construção civil, que caracterizam este mercado. Apesar disto, ainda são vistos métodos arcaicos de extração dos blocos de rocha e, não raro, executados sobre forma de garimpos. Em conseqüência, ocorrem significativas perdas em todas as etapas do fluxo produtivo de rochas ornamentais. A presente dissertação apresenta uma metodologia de modelagem computacional de jazidas de rocha ornamental em maciço rochoso, como contribuição técnica ao setor, através de um caso real, exemplificado pela mina SOMIBRAS, no município de Capão Bonito - SP. Embora os procedimentos gerais adotados sejam semelhantes aos demais trabalhos de modelagem de depósitos minerais, verifica-se que em detalhes estes não se aplicam diretamente, devido às peculiaridades características das jazidas de rocha ornamental: grande abundância de tipos litológicos, padrão estético, baixo valor agregado e sanidade estrutural. Um dos maiores obstáculos enfrentados pela pesquisa foi o mesmo problema encontrado em quase todos os depósitos ornamentais brasileiros: a falta generalizada de dados geológicos e/ou topográficos. Os trabalhos de levantamento de dados realizados nesta dissertação ressaltaram a grande importância desses dados, com especial destaque para o método geofísico GPR (Radar de penetração de solo), que possibilitou o mapeamento das fraturas em profundidade, e sua interpretação tridimensional. ) Os benefícios da aplicação das técnicas computacionais são significativos e poderão encorajar futuros esforços de pesquisa para melhorar o aproveitamento econômico da jazida de rochas ornamentais, bem como a de planejar corretamente os avanços das frentes de lavra e disposição de materiais de descartes.The brasilian dimension stone industry has substantially increased lately, mainly by exportation of its refined or semi-refined products. The brasilian markets show a great variety and dynamism to attend the new aesthetic tendency of civil constructions. In spite of this, the archaic methods of block extractions are frequently shown yet. The present master thesis presents a methodology for computational modeling of dimensional stone quarry as a technical contribution to the sector of ornamental rocks, illustrated by a real exemple case of SOMIBRAS mine at Capão Bonito, SP. Although its general procedures are similars to the others mineral modeling works, this work have confirmed that in details the same procedures aren´t directly applied in this case, due to the peculiar characteristics of dimension stones. One of great problems faced by this study was the same difficulties found in major parts of brasilian dimension stone quarries: a generalized absence of geological and/or topographic data. The field searches emphasized the importance of these data, with special distinction for GPR system (Ground Penetration Radar) that provided mapping of deep fractures and its spatial interpretations. The benefits of computational technique are significants and could stimulate new research efforts to improve profits, feasibility and economical plans of dimensional stone quarries
Bulgaria: Asen Filipov Stoyanov ,follow-up #1
No full textA document from Amnesty Internationals Urgent Action Networ
REVIEW OF POWER SOURCES OF UNMANNED SURFACE VEHICLES
No full textThe article deals with small unmanned surface vehicles (USV), which main objective is exploration of seas and oceans as well as use for military purposes. The subject matter of this study is to analyze power sources providing power supply for all USVs power consuming units. There has been offered a review of actual-to-date USVs both of Russian and foreign manufacturing, which autonomous operation can last up to 3 months. The author has analyzed general characteristics of USVs, and paid special attention to the power sources and to consuming energy by the vehicles. Approximate total power obtained from USV electric sources makes 300-1000 W. It should be noted that USV electric power sources are not only accumulators and generators, but solar batteries and wind power generators. To save power USVs use sailing rigging, or apply wave glider’s technology where wave power is harvested to increase mobility of the vehicle. A distinctive feature of some USVs structure is placing solar batteries both on deck and on sales. A significant advantage of this structure is less power consumption at sufficient wind velocity and strengthening USV power system. There are considered not only single-hulled USVs, but also catamaran types (for gaining effective area to place additional solar batteries). Using data of USV structural features analysis, the author has inferred the factors influencing USV’s electric power system design, as well as perspectives of development of new types of unmanned crafts.</jats:p
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No full textA Teoria dos Jogos Diferenciais (TJD) teve origem em meados de 1950 com a pesquisa de Rufus Philip Isaacs, um pesquisador da RAND Corporation. Os pesquisadores que tinham contato com essa teoria logo descobriram que o tra- balho de John Von Neumann e Oskar Morgenstern [9] não era suciente para resolver tais problemas. Os estudos relacionados a TJD caram ligados direta- mente ao estudo de sistemas dinâmicos. Sendo assim, assuntos ligados a Teoria de Controle Ótimo começaram a tomar a frente nas pesquisas sobre TJD. O Jogo do Motorista Assassino (JMA), se tornou um JP padrão no estudo em TJD. A solução de JDs está ligada a existência de controles ótimos. O Princípio da Programação Dinâmica e o Princípio do Mínimo, propostos por Richard Ernst Bellman e Lev Semyonovitch Pontryagin, respectivamente, se tornam condições para a determinação de estratégias (controles) ótimas. A existência é garantida por um teorema proposto por Aleksei Fyodorovich Filipov. Os JDs serão apresentados de maneira formal, junto com a função de Payo. Daremos especial atenção aos JPs. Os JPs são JDs de Dois Jogadores com Soma Zero, conceito bastante difundido em TJD. No caso dos JPs, teremos dois jogadores: um Perseguidor e um Evasor. A função de Payo será estudada de acordo com a sua convergência a Funçao de Valores de um JD. A continuidade da função de valores será provada, utilizando a Equação de Hamilton-Jacobi- Isaacs (EHJI). Um estudo qualitativo será feito sobre as condições de capturabilidade do Evasor pelo Perseguidor. Utilizaremos o Princípio do Mínimo como ferramenta princi- pal para determinarmos a Barreira S, que determina a região de capturabilidade do Evasor pelo Perseguidor.The Dierential Game Theory (DGT) originated in the mid 1950s with the research Rufus Philip Isaacs, a researcher at the RAND Corporation. Researchers who had contact with this theory soon discovered that the work of John von Neumann and Oskar Morgenstern [9] was not enough to solve such problems. Studies related to DGT were directly linked to the study of dynamical systems. Therefore, issues related to Optimal Control Theory began to take the lead in research on DGT. The Homicidal Chaueur Game (HCG) has become a standard PG of study in DGT. The DGs solution is attached to the existence of optimal controls. The Dynamic Programming Principle and The Minimum Principle proposed by Richard Ernst Bellman and Lev Semyonovitch Pontryagin, respectively, become condi- tions for determining optimal strategies (controls). The existence is guaranteed by a theorem proposed by Aleksei Fyodorovich Filipov. The DGs will be presented formally, along with the Payo function. We will give special attention to DGs. The PGs are Two Player Zero-Sum DG, a concept widespread in DGT. In the case of PGs, we have two players: a Pursuer and an Evader. The Payo Function will be studied according to their convergence to the Value Function of a DG. The continuity of the Value Function will be tested, using the Hamilton-Jacobi-Isaacs Equation (HJIE). A qualitative study will be done about the conditions of capturability of Evader by the Pursuer. We will use the Minimum Principle as the main tool to deter- mine the Barrier S, which determines the capturability region of Evader by the Pursuer
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