Layout and material gradation in topology optimization of functionally graded structures: a global-local approach

By means of continuous topology optimization, this paper discusses the influence of material gradation and layout in the overall stiffness behavior of functionally graded structures. The formulation is associated to symmetry and pattern repetition constraints, including material gradation effects at both global and local levels. For instance, constraints associated with pattern repetition are applied by considering material gradation either on the global structure or locally over the specific pattern. By means of pattern repetition, we recover previous results in the literature which were obtained using homogenization and optimization of cellular materials.

Design methodology of piezoelectric energy-harvesting skin using topology optimization

Abstract This paper describes a design methodology for piezoelectric energy harvester s that thinly encapsulate the mechanical devices and expl oit resonances from higher- order vibrational modes. The direction of polarization determines the sign of the pi ezoelectric tensor to avoid cancellations of electric fields from opposite polarizations in the same circuit. The resultant modified equations of state are solved by finite element method (FEM). Com- bining this method with the solid isotropic material with penalization (SIMP) method for piezoelectric material, we have developed an optimization methodology that optimizes the piezoelectric material layout and polarization direc- tion. Updating the density function of the SIMP method is performed based on sensitivity analysis, the sequen- tial linear programming on the early stage of the opti- mization, and the phase field method on the latter stage

Melhoria de fluxos no armazém de componentes da Bosch Termotecnologia S.A.

A gestão de um armazém de componentes de uma qualquer empresa produtiva é uma das principais tarefas a desempenhar no seio desta, pois a mesma afecta toda a cadeia de abastecimento de entrega do produto final, sendo o armazém de componentes o início da cadeia interna. Qualquer dificuldade que surja no desenrolar das actividades associadas poderá causar impactos prejudiciais nos processos consequentes. A melhoria do principal processo do armazém, correspondente à satisfação dos pedidos de material dos processos a jusante, é algo que trará benefícios a toda a cadeia, ao mesmo tempo que são melhoradas as condições de trabalho, eliminando o desperdício e tornando o processo mais eficiente. Não obstante deste processo, ainda existe a necessidade de recolher e gerir informações referentes aos diferentes processos do armazém da maneira mais rápida possível, para actuar de acordo com as necessidades. A falta de informação relativamente ao estado de um processo também poderá influenciar os processos seguintes de forma negativa. O projecto aqui apresentado foi realizado no armazém de componentes da Bosch Termotecnologia S.A., em Aveiro, tendo como objectivo mostrar a importância da movimentação de material e também de informação dentro desta área, criando ao mesmo tempo a melhoria tanto dos fluxos de material como dos fluxos de informação. Serão apresentadas diferentes implementações que foram desenvolvidas com o intuito de criar melhoria nos fluxos: a criação de novos fluxos de informação para o processo de recepção de material, com o intuito de recolher informação que até agora não era perceptível, para depois actuar na melhoria do processo; a criação de áreas dedicadas dentro da área de picking, de modo a atingir uma redução no número de colaboradores afectos ao processo de picking; a implementação de uma célula de repacking, de modo a remover esta actividade do processo de picking; bem como todas as actividades realizadas com o objectivo de implementar as melhorias propostas.

Induktiokoneiden vyyhdenvalmistuksen ja kääminnän tulevaisuuden kapasiteettia sekä läpimenoajan lyhenemistä tukeva layout

Tämä insinöörityö tehtiin ABB Oy:n Pitäjänmäen konetehtaan Sähkökoneet -yksikölle. Työssä suunniteltiin Induktiokoneiden vyyhdenvalmistuksen ja kääminnän tulevaisuuden kapasiteettia sekä läpimenoajan lyhenemistä tukeva layout. Työssä kiinnitettiin huomiota myös järkeviin materiaalivirtoihin sekä työturvallisuuden parantamiseen. Työ aloitettiin kartoittamalla vyyhdenvalmistusten ja käämintöjen tilanne sekä tutkittiin tulevaisuudelle ennustettu kuormitus. Kartoituksen perusteella mietittiin, mitä välttämättömiä muutoksia tarvitsee tulevaisuudessa tehdä työtapojen, koneiden ja työpisteiden suhteen. Läpimenoaikoja tutkittiin ja mietittiin keinoja sen lyhentämiseksi. Edellä mainittujen perusteella lähdettiin suunnittelemaan layout, joka toteuttaisi kaikki vaaditut kriteerit mahdollisimman kattavasti. Työn tuloksena syntyi layout-ehdotus, joka kattaa vaaditut kriteerit käytössä oleviin tiloihin ja niiden sijaintiin nähden parhaalla mahdollisella tavalla. Tämä ehdotus on varsin varteenotettava, mikäli tuotantokäyttöön suunniteltu käsieristyskone ei sovellu sille tarkoitettuun käyttötarkoitukseen, eikä näin ollen tule tuotantokäyttöön. Tällä layoutilla on mahdollista parantaa työturvallisuutta raskaiden taakkojen kuljetusten vähentyessä, lyhentää läpimenoaikoja turhien siirtelyiden poistuttua ja tehdä materiaalivirroista loogisia. Näillä parannuksilla varmistuisi tulevaisuuden kuormituksen läpimenon kyseisillä osastoilla. Tästä lopputyöstä on hyötyä ABB:llä käynnissä olevalle vyyhdenvalmistus projektille, jonka tehtävänä on kehittää vyyhdenvalmistusta. Tämän lisäksi projektin tarkoituksena on miettiä vyyhdenvalmistukselle uusi layout, mikäli se nähdään tarpeelliseksi. Tekemäni kartoitus, layout ja parannusehdotukset ovat tarpeellisena pohjatietona tämän projektin edetessä. Tekemiäni parannusehdotuksia on jo osittain otettu käyttöön vyyhdenvalmistuksessa. Parannusehdotuksiani tullaan vyyhdenvalmistuksessa toteuttamaan, kokeilemaan ja kehittämään eteenpäin vielä jatkossakin.

Typographic layout and first impressions: testing how changes in text layout influence reader's judgments of documents

This study explores how the typographic layout of information influences readers' impressions of magazine contents pages. Thirteen descriptors were used in a paired comparison procedure that assessed whether participants' rhetorical impressions of a set of six controlled documents change in relation to variations in layout. The combinations of layout attributes tested were derived from the structural attributes associated with three patterns of typographic differentiation (high, moderate, and low) described in a previous study (see Moys, 2014). The content and the range of stylistic attributes applied to the test material were controlled in order to focus on layout attributes. Triangulation of the quantitative and qualitative data indicates that, even within the experimental confines of limited stylistic differentiation, the layout attributes associated with patterns of high, moderate, and low typographic differentiation do influence readers' rhetorical judgments. In addition, the findings emphasize the importance of considering inter-relationships between clusters of typographic attributes rather than testing isolated variables.

Análise e melhoria de layout de processo na indústria de beneficiamento de couro

A aplicação de técnicas de estudo de sistemas em ambientes industriais com grande concorrência, é cada vez mais significativa devido às modificações e flexibilidade de produção exigidas. A aplicação de técnicas de análise e ajustes de layouts são algumas destas técnicas que podem trazer resultados competitivos positivos. O presente trabalho descreve os tipos de layouts existentes, com suas aplicações, vantagens e desvantagens com a finalidade de analisar e propor melhorias em layouts de processo na indústria coureira. O trabalho enfoca ainda os principais pontos a serem considerados quando da criação de um novo layout ou do ajuste e/ou melhoria de um existente. Para tal, foi realizado um estudo de caso utilizando a técnica de Melhoria de Layout de Silveira (1998), com a aplicação do Planejamento Sistemático de Layout em um layout de processo do setor da Secagem, característico em uma indústria beneficiadora de couro. Os resultados obtidos traduzem o re-arranjo de seus postos de trabalho com redução do fluxo de material de acordo com a aproximação de postos com relações de afinidade. Essa alteração possibilitou uma melhor organização espacial dos postos de trabalho e um melhor controle da produção, através da separação natural dos lotes. A metodologia adotada pode ser utilizada como ferramenta de melhoria nos demais setores, tanto da própria empresa, como do mercado coureiro em geral.

Uma análise de modelos quantitativos aplicados a solução de problemas de Plant - Layout

Este trabalho tem por objetivo reunir e analisar os modelos quantitativos mais comumente usados como suporte às atividades dos especialistas, responsáveis, nas empresas, pela consecução do melhor arranjo. Enfase especial é dispensada à análise dos modelos computacionais que, de fato, constitui a parte central da monografia. Não há qualquer pretensão de originalidade para os conceitos e para o material aqui apresentado.

Utilização de 5S, Kanban e Layout para a melhoria do controle de estoque em um varejo de materiais para construção

Many small businesses suffer from a lack of control of goods stored. This lack of control affects other areas of the company as purchase, that can’t buy material in an advanced and accurated way. It also affects services provided by the company, especially when it is a store because for sell something it is necessary to have the material in the right time. Futhermore, the business isn’t able to identify obsolete items in stock, theft and vandalism, loss or damage to materials. All of these disorders can be converted into financial losses that make much difference to a small business that needs to remain competitive in the market facing the giants while generating a profit that allows it to invest in their growth. Therefore, any unnecessary expense is exceedingly harmful and any savings already differentiates it from other companies of similar size. This study deals with the application of production engineering tools as 5S, kanban and layout in a building materials retail to tackle problems that prevent this company to have a stock organized and accurated. Finally, we recorded gains that the company reached with the implementation of part of the solution proposed

Impacts of seawater acidification on mantle gene expression patterns of the Baltic Sea blue mussel: implications for shell formation and energy metabolism, link to supplementary material

Marine organisms have to cope with increasing CO2 partial pressures and decreasing pH in the oceans. We elucidated the impacts of an 8-week acclimation period to four seawater pCO2 treatments (39, 113, 243 and 405 Pa/385, 1,120, 2,400 and 4,000 µatm) on mantle gene expression patterns in the blue mussel Mytilus edulis from the Baltic Sea. Based on the M. edulis mantle tissue transcriptome, the expression of several genes involved in metabolism, calcification and stress responses was assessed in the outer (marginal and pallial zone) and the inner mantle tissues (central zone) using quantitative real-time PCR. The expression of genes involved in energy and protein metabolism (F-ATPase, hexokinase and elongation factor alpha) was strongly affected by acclimation to moderately elevated CO2 partial pressures. Expression of a chitinase, potentially important for the calcification process, was strongly depressed (maximum ninefold), correlating with a linear decrease in shell growth observed in the experimental animals. Interestingly, shell matrix protein candidate genes were less affected by CO2 in both tissues. A compensatory process toward enhanced shell protection is indicated by a massive increase in the expression of tyrosinase, a gene involved in periostracum formation (maximum 220-fold). Using correlation matrices and a force-directed layout network graph, we were able to uncover possible underlying regulatory networks and the connections between different pathways, thereby providing a molecular basis of observed changes in animal physiology in response to ocean acidification.

The Material Dynamics of a London-French Blog: A Multimodal Reading of Migrant Habitus

Through a fine-grained reading of a London-French blog, this article aims to shed light on the lived experience of the French community in London. The ethnosemiotic conceptual framework brings together ethnographic and semiotic schools of thought, focusing in particular on Pierre Bourdieu’s concept of habitus and Gunther Kress’s multimodal social semiotic analytical model. Habitus is broken down into its material manifestations of habitat, habit and habituation, all displayed in the blog and revealing of the blogger’s identity and positioning within the migration setting. As all modes are considered to be of equal semiotic potential, equivalent emphasis is placed on the multiple modes of meaning-making present in the blog, such as layout, colour, typography and language. By examining the dynamic relationships between blogger and audience, subjectivity and objectivity, on-line and on-land habitus, and intermodal dynamics themselves, through the prism of multimodality, hidden facets of the blogger’s cultural identity and sense of community belonging within the diasporic context begin to materialise.

Evaluating Invariances in Document Layout Functions

With the development of variable-data-driven digital presses - where each document printed is potentially unique - there is a need for pre-press optimization to identify material that is invariant from document to document. In this way rasterisation can be confined solely to those areas which change between successive documents thereby alleviating a potential performance bottleneck. Given a template document specified in terms of layout functions, where actual data is bound at the last possible moment before printing, we look at deriving and exploiting the invariant properties of layout functions from their formal specifications. We propose future work on generic extraction of invariance from such properties for certain classes of layout functions.

Effect Of Platform Connection And Abutment Material On Stress Distribution In Single Anterior Implant-supported Restorations: A Nonlinear 3-dimensional Finite Element Analysis.

Although various abutment connections and materials have recently been introduced, insufficient data exist regarding the effect of stress distribution on their mechanical performance. The purpose of this study was to investigate the effect of different abutment materials and platform connections on stress distribution in single anterior implant-supported restorations with the finite element method. Nine experimental groups were modeled from the combination of 3 platform connections (external hexagon, internal hexagon, and Morse tapered) and 3 abutment materials (titanium, zirconia, and hybrid) as follows: external hexagon-titanium, external hexagon-zirconia, external hexagon-hybrid, internal hexagon-titanium, internal hexagon-zirconia, internal hexagon-hybrid, Morse tapered-titanium, Morse tapered-zirconia, and Morse tapered-hybrid. Finite element models consisted of a 4×13-mm implant, anatomic abutment, and lithium disilicate central incisor crown cemented over the abutment. The 49 N occlusal loading was applied in 6 steps to simulate the incisal guidance. Equivalent von Mises stress (σvM) was used for both the qualitative and quantitative evaluation of the implant and abutment in all the groups and the maximum (σmax) and minimum (σmin) principal stresses for the numerical comparison of the zirconia parts. The highest abutment σvM occurred in the Morse-tapered groups and the lowest in the external hexagon-hybrid, internal hexagon-titanium, and internal hexagon-hybrid groups. The σmax and σmin values were lower in the hybrid groups than in the zirconia groups. The stress distribution concentrated in the abutment-implant interface in all the groups, regardless of the platform connection or abutment material. The platform connection influenced the stress on abutments more than the abutment material. The stress values for implants were similar among different platform connections, but greater stress concentrations were observed in internal connections.

Improved Selective Cholesterol Adsorption By Molecularly Imprinted Poly(methacrylic Acid)/silica (pmaa-sio₂) Hybrid Material Synthesized With Different Molar Ratios.

The present paper describes the synthesis of molecularly imprinted polymer - poly(methacrylic acid)/silica and reports its performance feasibility with desired adsorption capacity and selectivity for cholesterol extraction. Two imprinted hybrid materials were synthesized at different methacrylic acid (MAA)/tetraethoxysilane (TEOS) molar ratios (6:1 and 1:5) and characterized by FT-IR, TGA, SEM and textural data. Cholesterol adsorption on hybrid materials took place preferably in apolar solvent medium, especially in chloroform. From the kinetic data, the equilibrium time was reached quickly, being 12 and 20 min for the polymers synthesized at MAA/TEOS molar ratio of 6:1 and 1:5, respectively. The pseudo-second-order model provided the best fit for cholesterol adsorption on polymers, confirming the chemical nature of the adsorption process, while the dual-site Langmuir-Freundlich equation presented the best fit to the experimental data, suggesting the existence of two kinds of adsorption sites on both polymers. The maximum adsorption capacities obtained for the polymers synthesized at MAA/TEOS molar ratios of 6:1 and 1:5 were found to be 214.8 and 166.4 mg g(-1), respectively. The results from isotherm data also indicated higher adsorption capacity for both imprinted polymers regarding to corresponding non-imprinted polymers. Nevertheless, taking into account the retention parameters and selectivity of cholesterol in the presence of structurally analogue compounds (5-α-cholestane and 7-dehydrocholesterol), it was observed that the polymer synthesized at the MAA/TEOS molar ratio of 6:1 was much more selective for cholesterol than the one prepared at the ratio of 1:5, thus suggesting that selective binding sites ascribed to the carboxyl group from MAA play a central role in the imprinting effect created on MIP.