Characterization of cleaners accidents in the Portuguese service sector

This paper characterizes work accidents at Portuguese industrial cleaning companies, operating in the service sector, through the application of ESAW methodology. Data was codified based on the analysis of 748 accident claims to insurance companies (number of days lost 1 working day) in 3 large industrial cleaning companies for the period 2001-2003. Slipping and falling in the same level was the main deviation from the normal working process in the moment of the accident (in 25% of the accidents); uncoordinated movements was the second cause of accidents (14%); falls of persons to a lower level was the third cause of accidents (~10%), including falls from stairs (~7%) and falls from ladders and mobile ladders (~2%); globally, body movement under or with physical stress, including lifting, carrying, putting down, bending down, twisting, turning, trading badly, twisting leg or ankle and slipping without falling, were the cause in 17% of the accidents. Lower limbs were injured in ~25% of the accidents, hand and fingers in ~14%, the eye in ~4% and the back in ~9% of the accidents. An incidence rate of 3,580 accidents/100,000 employees was found to the sector (2003 data).

Exposição ocupacional a compostos orgânicos voláteis e a matéria particulada na limpeza automóvel em parques de estacionamento

Mestrado em Segurança e Higiene no Trabalho

A survey of technologies and applications for climbing robots locomotion and adhesion

The interest in the development of climbing robots has grown rapidly in the last years. Climbing robots are useful devices that can be adopted in a variety of applications, such as maintenance and inspection in the process and construction industries. These systems are mainly adopted in places where direct access by a human operator is very expensive, because of the need for scaffolding, or very dangerous, due to the presence of an hostile environment. The main motivations are to increase the operation efficiency, by eliminating the costly assembly of scaffolding, or to protect human health and safety in hazardous tasks. Several climbing robots have already been developed, and other are under development, for applications ranging from cleaning to inspection of difficult to reach constructions. A wall climbing robot should not only be light, but also have large payload, so that it may reduce excessive adhesion forces and carry instrumentations during navigation. These machines should be capable of travelling over different types of surfaces, with different inclinations, such as floors, walls, or ceilings, and to walk between such surfaces (Elliot et al. (2006); Sattar et al. (2002)). Furthermore, they should be able of adapting and reconfiguring for various environment conditions and to be self-contained. Up to now, considerable research was devoted to these machines and various types of experimental models were already proposed (according to Chen et al. (2006), over 200 prototypes aimed at such applications had been developed in the world by the year 2006). However, we have to notice that the application of climbing robots is still limited. Apart from a couple successful industrialized products, most are only prototypes and few of them can be found in common use due to unsatisfactory performance in on-site tests (regarding aspects such as their speed, cost and reliability). Chen et al. (2006) present the main design problems affecting the system performance of climbing robots and also suggest solutions to these problems. The major two issues in the design of wall climbing robots are their locomotion and adhesion methods. With respect to the locomotion type, four types are often considered: the crawler, the wheeled, the legged and the propulsion robots. Although the crawler type is able to move relatively faster, it is not adequate to be applied in rough environments. On the other hand, the legged type easily copes with obstacles found in the environment, whereas generally its speed is lower and requires complex control systems. Regarding the adhesion to the surface, the robots should be able to produce a secure gripping force using a light-weight mechanism. The adhesion method is generally classified into four groups: suction force, magnetic, gripping to the surface and thrust force type. Nevertheless, recently new methods for assuring the adhesion, based in biological findings, were proposed. The vacuum type principle is light and easy to control though it presents the problem of supplying compressed air. An alternative, with costs in terms of weight, is the adoption of a vacuum pump. The magnetic type principle implies heavy actuators and is used only for ferromagnetic surfaces. The thrust force type robots make use of the forces developed by thrusters to adhere to the surfaces, but are used in very restricted and specific applications. Bearing these facts in mind, this chapter presents a survey of different applications and technologies adopted for the implementation of climbing robots locomotion and adhesion to surfaces, focusing on the new technologies that are recently being developed to fulfill these objectives. The chapter is organized as follows. Section two presents several applications of climbing robots. Sections three and four present the main locomotion principles, and the main "conventional" technologies for adhering to surfaces, respectively. Section five describes recent biological inspired technologies for robot adhesion to surfaces. Section six introduces several new architectures for climbing robots. Finally, section seven outlines the main conclusions.

Strength prediction and experimental validation of adhesive joints including polyethylene, carbon-epoxy and aluminium adherends

Polyolefins are especially difficult to bond due to their non-polar, non-porous and chemically inert surfaces. Acrylic adhesives used in industry are particularly suited to bond these materials, including many grades of polypropylene (PP) and polyethylene (PE), without special surface preparation. In this work, the tensile strength of single-lap PE and mixed joints bonded with an acrylic adhesive was investigated. The mixed joints included PE with aluminium (AL) or carbon fibre reinforced plastic (CFRP) substrates. The PE substrates were only cleaned with isopropanol, which assured cohesive failures. For the PE CFRP joints, three different surfaces preparations were employed for the CFRP substrates: cleaning with acetone, abrasion with 100 grit sand paper and peel-ply finishing. In the PE AL joints, the AL bonding surfaces were prepared by the following methods: cleaning with acetone, abrasion with 180 and 320 grit sand papers, grit blasting and chemical etching with chromic acid. After abrasion of the CFRP and AL substrates, the surfaces were always cleaned with acetone. The tensile strengths were compared with numerical results from ABAQUS® and a mixed mode (I+II) cohesive damage model. A good agreement was found between the experimental and numerical results, except for the PE AL joints, since the AL surface treatments were not found to be effective.

Recuperação parcial da água de lavagem dos filtros utilizados no tratamento da água de piscinas de uso público

Mestrado em Engenharia Química. Ramo optimização energética na indústria química

MBR activated sludge filterability characterization in cross flow filtration

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia do Ambiente, perfil Sanitária

Avaliação da eficácia de tratamentos convencionais e aplicações alternativas para prevenir a biodeterioração em património cultural

Dissertação de Mestrado em Conservação e Restauro.Área de especialização: Pedra

The influence of sludge characteristics from fullscale MBR in membrane filterability

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia do Ambiente,perfil Sanitária

Gestão de resíduos produzidos num sistema de drenagem e tratamento de águas residuais

O presente trabalho centra-se na gestão de resíduos produzidos no sistema de drenagem e tratamento de águas residuais do município de Vila Nova de Gaia. A entidade onde decorreu o trabalho é uma empresa responsável pela distribuição de água e pela drenagem e tratamento de águas residuais. A empresa está certificada pela norma NP EN ISO 14001, desde 2001, sendo então um dos objectivos o enquadramento da gestão dos resíduos em estudo na referida norma, acompanhando os requisitos da mesma com vista ao seu total cumprimento. Outros dos objectivos foi estudar qual a opção de tratamento mais adequada a aplicar ao resíduo no seu local de armazenamento temporário com vista a minorar os seus impactes ambientais. De acordo com a caracterização analítica do resíduo e com os aspetos legais aplicáveis, foram também analisados os destinos finais possíveis e ambientalmente adequados ao resíduo. A medida proposta para a minimização de impactes no local de armazenamento temporário do resíduo foi a estabilização com cal nos leitos de secagem, disponíveis numa antiga ETAR de loteamento. O doseamento de cal a aplicar ao resíduo será de 10 kg de cal apagada comercial (Ca (OH)2) por uma tonelada de resíduo fresco com um período mínimo de secagem de 2 meses. Outra das medidas de minimização de impactes selecionada foi a implantação de uma cortina arbórea ao redor da instalação. Sendo o resíduo em estudo muito heterogéneo, constituído principalmente por areias, terras e gradados, a valorização foi equacionada mas não foram encontrados alternativas viáveis. O destino final considerado como mais adequado tendo em conta todas as características do resíduo e eluato, analisadas de acordo com o previsto no Decreto-Lei n.º 183/2009 de 10 de Agosto, foi o aterro para resíduos não perigosos. Foi também objecto do estudo a identificação e análise de todos os aspectos ambientais relacionados com a gestão de resíduos e a avaliação da sua significância. Dos aspectos ambientais identificados como significativos, destacam-se aqueles que ocorrem presentemente, os resíduos armazenados (gradados/limpeza de redes), e os que podem ocorrer em situações de emergência, fuga/derrame de óleos/combustíveis e cheiros/odores. De forma a minimizar os aspectos ambientais identificados, e de acordo com a norma NP EN ISO 14001, foram propostas ações que constam de um programa de gestão elaborado para este trabalho, onde se definem os objectivos, metas e prazos. As principais medidas propostas no programa de gestão foram: Estabilização com cal (inicial e reforço se necessário); melhoria do espaço envolvente; análise de questões de saúde ocupacional/segurança; adjudicação de prestação de serviços da recolha por operador licenciado; implantação da cortina arbórea; registo no SIRAPA; criação de planos de emergência ambiental e de segurança.

Climbing robots: a survey of technologies and applications

The interest in the development of climbing robots is growing rapidly. Motivations are typically to increase the operation efficiency by obviating the costly assembly of scaffolding or to protect human health and safety in hazardous tasks. Climbing robots are starting to be developed for applications ranging from cleaning to inspection of difficult to reach constructions. These robots should be capable of travelling on different types of surfaces, with varying inclinations, such as floors, walls, ceilings, and to walk between such surfaces. Furthermore, these machines should be capable of adapting and reconfiguring for various environment conditions and to be self-contained. Regarding the adhesion to the surface, they should be able to produce a secure gripping force using a light-weight mechanism. This paper presents a survey of different applications and technologies proposed for the implementation of climbing robots.

Revestimento de piso em pedra calcária: adequabilidade, patologia e manutenção

Dissertação para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização em Edificações

Graffiti nas edificações: identificação e resolução do problema

Trabalho final de Mestrado para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização em Edificações

Spectroscopy studies on conservation issues in modern and contemporary paintings

Dissertation presented to the Faculty of Sciences and Technology of New University of Lisbon in fulfilment of the requirements for the Master’s degree in Conservation and Restoration Specialization in easel painting

Como polir uma montanha: trabalho de projeto

Esta reflexão visa contextualizar o processo criativo da componente prática do Trabalho de Projecto – Objecto conferente do grau de Mestre em Teatro, especialização em Artes Performativas – Interpretação, e que consiste no solo Como polir uma montanha que teve lugar no Lavadouro Público de Carnide com Acolhimento do Teatro do Silêncio em Maio de 2014. O objectivo foi criar um espectáculo com base em acções de limpeza, utilizando os gestos quotidianos como elemento catalisador do processo criativo. Procurei, desta forma, espelhar algumas rotinas do dia-a-dia no campo abstracto das artes performativas, desconstruindo o espaço privado e servindo-me do corpo como ferramenta primordial na comunicação destas acções através do movimento. A premissa para este solo partiu da limpeza enquanto acção passível de gerar transformação no espaço e no tempo, e também no corpo e na mente. Inicialmente pensei que a limpeza era fundamental para a organização destes elementos, contudo o resultado levou-me a compreender que limpeza e organização podem ter pressupostos muito distintos. Fundamentei a minha pesquisa observando acções quotidianas de limpeza em contextos diversificados como a vivência rural, a vivência urbana e ao nível da memória – a minha e a de outros indivíduos – de como processamos determinados comportamentos observados desde a infância. Durante o processo de criação de Como polir uma montanha, surgiram diversas inquietações que me levaram a reflectir também sobre a problemática de ser criadora e intérprete a solo, e de como esta questão é transversal à noção de si mesmo perante o outro. Esta noção leva-me a questionar o limiar que separa, mas também une, o palco e a plateia. Por isso integrei o público na acção cénica, através de elementos que propunham uma observação participativa do espectáculo.

Destruction of the tar present in syngas by combustion in porous media

The cleaning of syngas is one of the most important challenges in the development of technologies based on gasification of biomass. Tar is an undesired byproduct because, once condensed, it can cause fouling and plugging and damage the downstream equipment. Thermochemical methods for tar destruction, which include catalytic cracking and thermal cracking, are intrinsically attractive because they are energetically efficient and no movable parts are required nor byproducts are produced. The main difficulty with these methods is the tendency for tar to polymerize at high temperatures. An alternative to tar removal is the complete combustion of the syngas in a porous burner directly as it leaves the particle capture system. In this context, the main aim of this study is to evaluate the destruction of the tar present in the syngas from biomass gasification by combustion in porous media. A gas mixture was used to emulate the syngas, which included toluene as a tar surrogate. Initially, CHEMKIN was used to assess the potential of the proposed solution. The calculations revealed the complete destruction of the tar surrogate for a wide range of operating conditions and indicated that the most important reactions in the toluene conversion are C6H5CH3 + OH <-> C6H5CH2 + H2O, C6H5CH3 + OH <-> C6H4CH3 + H2O, and C6H5CH3 + O <-> OC6H4CH3 + H and that the formation of toluene can occur through C6H5CH2 + H <-> C6H5CH3. Subsequently, experimental tests were performed in a porous burner fired with pure methane and syngas for two equivalence ratios and three flow velocities. In these tests, the toluene concentration in the syngas varied from 50 to 200 g/Nm(3). In line with the CHEMKIN calculations, the results revealed that toluene was almost completely destroyed for all tested conditions and that the process did not affect the performance of the porous burner regarding the emissions of CO, hydrocarbons, and NOx.