Prevenção de riscos profissionais na construção de edifícios com estruturas em aço leve

A utilização de estruturas em aço leve em edifícios de pequeno porte tem tido um assinalável crescimento nos últimos anos, em diversos países do mundo, fruto das suas assinaláveis vantagens em termos custos, sistematização da produção, facilidade de montagem e de rapidez de execução. As caraterísticas deste sistema construtivo contribuem para a diminuição dos riscos profissionais normalmente associados à execução de estruturas tradicionais, em função da leveza dos elementos estruturais constituintes, da simplicidade das ligações, da repetição das operações de montagem, etc. Mas também introduzem outros riscos que importa considerar no planeamento da segurança de obras deste tipo, nomeadamente, os que resultam da falta de sedimentação das equipas de trabalho, frequentemente associada à sua inexperiência e informalidade, em virtude da simplicidade e da rapidez de construção permitidas pelo sistema. Relevam aqui os riscos de natureza organizacional, sem por de parte os riscos físicos, principalmente relacionados com as operações de montagem, cuja importância vem crescendo à medida que este sistema construtivo vai tendo aplicações em projetos mais complexos e em obras de maior porte. Levantam-se então, para este tipo de obras preocupações diferentes na prevenção de riscos profissionais, quando comparadas com as obras tradicionais. Ao congregar um vasto conjunto de países ibero-americanos em que este sistema construtivo tem tido grande recetividade, a rede temática CYTED despoletou a reflexão sobre este tema, como se procura analisar na presente comunicação.The use of lightweight steel frame structures in small buildings has had a remarkable growth in recent years in many countries, because of their remarkable advantages in costs, production organization, ease of fitting and execution speed. The characteristics of this building system contribute for the reduction of occupational risks normally associated to conventional building structures, due to the lightness of the structural constituents, the simplicity of connections, the repetition of assembly operations, etc. But also introduce other relevant risks in safety planning, including those resulting from the lack of settling of work teams, often associated with inexperience and informality, due to the simplicity and construction provided by the system. Organizational risks are relevant under this topic as well as the increase of physical risks, mainly related to the assembly operations, the importance of which tends to increase as the system is used in more complex projects and larger works. In view of the above, different concerns in the prevention of occupational risks may arise for this type of works, when compared to traditional construction. By bringing a wide range of Latin American countries in which this system has had considerable receptivity, the thematic network CYTED triggered the debate on this issue, as analysed in this paper

Proteolysis of ovine and caprine Caseins in solution by enzymatic extracts from flowers of Cynara cardunculuso

Primary proteolysis of ovine and caprine Na-caseinate at 30°C in phosphate buffer at pH 6.5 or 5.5 in the absence of NaCl and at pH 5.2 with 5% (w/v) NaCl by cardosins in aqueous extracts of Cynara cardunculus flowers was investigated using urea-polyacrylamide gel electrophoresis and reversed-phase high performance liquid chromatography. Caprine caseinate underwent more extensive degradation than ovine caseinate under the same conditions (pH 6.5 and pH 5.5); proteolysis of b- and as-caseins in ovine and, to a lesser extent, in caprine caseinates was reduced in the presence of 5% (w/v) NaCl. Peptide profiles of the pH 4.6-soluble extract had different patterns throughout ripening arising from the different specificity of cardosins toward ovine and caprine Na-caseinates. The major cleavage sites in ovine (caprine) caseinate were Phe105-Met106 (Lys116-Thr117) for k-casein, Leu127-Thr128 and Leu190-Tyr191 (Glu100-Thr101, Leu127-Thr128, Leu136-Pro137 and Leu190- Tyr191) for b-casein, Phe23-Val24 (Phe23-Val24, Trp164-Tyr165 and Tyr173-Thr174) for as1-casein and Phe88-Tyr89 (Ser9-Ser10, Phe88-Tyr89 and Tyr179-Leu180) for as2-casein

Documentos de prevenção de riscos profissionais na construção na transposição das diretivas comunitárias para Portugal

A Diretiva Comunitária nº 92/57/CEE (Diretiva Estaleiros Temporários ou Móveis) foi transposta pela generalidade dos países europeus nos anos seguintes ao da sua publicação. Se bem que o documento de base para a transposição seja o mesmo, cada país europeu teve necessidade de o adaptar à sua realidade legislativa, durante o processo de transposição, observando-se, hoje em dia, algumas diferenças entre os instrumentos legais em vigor nos diversos países. Em Portugal, a transposição da Diretiva teve lugar em 1995, mas o instrumento legal atualmente em vigor data de 2003 (Decreto-Lei nº 273/2003, de 29 de Outubro). O diploma estipula quatro documentos essenciais de prevenção dos riscos profissionais em estaleiros de construção: – o plano de segurança e saúde, a comunicação prévia, as fichas de procedimentos de segurança e a compilação técnica – e introduz novos intervenientes no processo da construção – os coordenadores de segurança e saúde – explicitando as suas funções e obrigações. A rede temática CYTED tem permitido observar as diferenças de abordagens da prevenção de riscos profissionais em países ibero-americanos e identificar as suas melhores práticas no sentido do usufruto comum. Ao mesmo tempo, revelou algumas especificidades interessantes da prática de cada país da rede, que importa partilhar e refletir. Esta comunicação apresenta algumas especificidades da prática Portuguesa que se analisam sumariamente: a adoção de um só documento de prevenção de riscos profissionais da fase de construção, transversal a todo o processo construtivo; a sua simplificação por fichas de utilização mais prática, quando estão em causa pequenos trabalhos tipificados; a constituição de um documento de prevenção para a fase de utilização do empreendimento construído, da responsabilidade do dono da obraThe Community Directive No. 92/57/EEC (Temorary or Mobile sites Directive) has been implemented by most European countries in the years following its publication. While the basic document for the implementation is the same, each European country had to adapt it to its legislative reality, during the transposition process; therefore, various differences between the legal instruments in force in different countries may be observed, nowadays. In Portugal, the transposition of the Directive took place in 1995, but the legal instrument currently in force dates from 2003 (Decree-Law No. 273/2003 of 29 October). The law stipulates four essential documents for the prevention of occupational risks on construction sites: - the health and safety plan, the prior notice, the safety procedures and technical file - and introduces new actors in the construction process - health and safety coordinators - explaining their duties and obligations. The thematic network CYTED has allowed to observe differences between the approaches followed in Ibero-American countries for occupational risk prevention and identified their best practices for mutual benefit. At the same time, it revealed some interesting specifics in the practices of each country in the network, that it is interesting to share and reflect. This paper presents some specificities of Portuguese practice that are briefly analysed: the adoption of a single document for occupational risks prevention of in construction, across the whole construction process; the simplificationof this document through more easy to use forms usable for smaller works; the creation of a document to prevent the utilization phase of the project under the responsibility of the developer

Remote Boundary-Scan Testbench with Extended SFV Commands

Este artigo propõe um conjunto estendido de comandos SVF, desenhados para permitir a monitorização em tempo real de combinações lógicas proibidas em grupos seleccionados de pinos com boundary-scan. O programa completo em SVF é escrito e executado através de um controlador de teste com IP próprio, que permite o controlo remoto do sistema alvo. É apresentado um exemplo de aplicação, usando uma carta boundary-scan com duas cadeias de teste.This paper proposes an extended set of SVF commands, which were designed to support real-time monitoring of forbidden patterns at selected groups of boundary-scan pins. The complete SVF program is written and run using an integrated low-cost test controller with its own IP address, enabling remote control of the target hardware. An application example is presented, using a simple dual-port boundary-scan board

Evolution of free fatty acid profile during ripening in cheeses manufactured from bovine, ovine and caprine milks with extracts of Cynara cardunculus as coagulant

Changes in the concentrations of free fatty acids (FFA) in bovine, ovine and caprine milk cheeses manufactured with a plant rennet (flowers of Cynara cardunculus) were studied throughout a 68-day ripening period. The long-chain saturated (C16 : 0 and C18 : 0) and unsaturated (C18 : 1, C18 : 2, and C18 : 3) FFA were the most abundant at all stages of ripening. The overall concentration of FFA in fresh cheese was 3598, 3538 and 3868 mg/kg cheese for bovine, ovine and caprine milk cheeses, respectively; these values increased to 5047, 6517 and 5257 mg/kg cheese, respectively, by 68 days, of which 1171, 1734 and 1791 mg/kg cheese, respectively, were accounted for by C4 : 0 – C12 : 0. The FFA that showed the highest fractional increase by 68 days of ripening in bovine milk cheese were C4 : 0, C6 : 0, C8 : 0, C12 : 0, C18 : 1 and C18 : 2; in ovine milk cheese they were C4 : 0, C6 : 0, C8 : 0, C10 : 0, C14 : 0, and C18 : 1; and in caprine milk cheese they were C4 : 0, C8 : 0, C10 : 0, C14 : 0 and C18 : 1

Waste identification diagrams

CLME'2011 / IIICEM – 6º Congresso Luso-Moçambicano de Engenharia - 3º Congresso de Engenharia de Moçambique Maputo, 29Ago - 2Set 2011 - Edições INEGI 2011, (ISBN: 978-972-8826-24-6), Ref: CLME’2011_0912AThe most popular and perhaps the most effective way to represent the material flow in production units is the diagram known as Value Stream Map (VSM). Moreover these maps are also used to help in the identification of waste as well as a tool to support continuous improvement. Nevertheless, many of VSM limitations are known and thus there is room for the creation of other more effective ways to represent productive units as well as helping the identification of production waste. This paper presents a new graphic representation model for production units, as a tool to identify three forms of waste, designated as Waste Identification Diagram (WID), which aims to provide information to top managers in a much more effective format. The WID is a network of blocks and arrows, showing visually the throughput times, idle capacity, transport effort, changeover times and work-in-process levels. To illustrate the main features of this new tool, the paper includes a WID of a real production unity

Poly-dodecahedrane: A new allotrope of carbon

Carbon is the most important chemical element and the theoretical study of its new allotropes can be of great interest. In this study, regular dodecahedron (dodecahedrane) oligomers (n = 1, 3, 5, 7, 9, 11, 13) by extending the dodecahedrane units in 3-dimensions were designed. Then, a theoretical study was conducted on their structures and electronic properties as potential new carbon allotrope. The cohesive energy (Ecoh) and $\Delta$G, were calculated. Experimental observations indicate that the Ecoh rises as the number of dodecahedrane units increases, whereas the Gibbs free energy change $\Delta$G decreases with an increase in the number of dodecahedrane units. The HOMO-LUMO energy gap (Eg) values, which represent electronic properties, decrease with increasing number of dodecahedrane units. Density functional theory (DFT) calculations of the novel carbon allotropes polydodecahedrane nanostructures have unveiled a previously unobserved symmetry, indicating intrinsic metallic behavior. The symmetrical distribution of partial charges was found in molecular electrostatic potential (MEP) diagrams for all oligomers, showing a tendency of the structures to maintain a symmetrical structural order as the number of monomer units increases. In addition, natural bond orbital (NBO) analysis of 13-units oligomer as largest designed structure reveals near-$sp^3$ hybridization for different carbons. Based on the calculated results, the structures have a tendency to extend in 3-dimensions and form a covalent network of poly-dodecahedrane with a unique structure consisting of interconnected cyclopentane rings. The results show that this exclusive configuration exhibits theoretical stability and suggests the potential for poly-dodecahedrane to be regarded as a novel carbon allotrope

Dermal denticles and morphometrics of the sailfin roughshark Oxynotus paradoxus (Elasmobranchii, Oxynotidae), with comments on its geographic distribution

The dermal denticles of the sailfin roughshark Oxynotus paradoxus are described and illustrated with SEM pictures, based on two specimens captured at the Azores. The flank denticles are similar to those of O. centrina, with a central cusp flanked by two smaller lateral cusps, rising from the lateral ridges, and a secondary median cusp posterior to the main one. Differences in squamation between both species are described. Body proportions of the Azorean specimens are given and found to be consistent with those reported by previous authors. The published information shows depth of capture to have a mode at 570 m. A bathybenthic habitat has been suggested, with spring reproductive migrations to the continental shelf. The presence of this species in the Azores and Mid-Atlantic Ridge represents a significant westward extension of its previously known geographic distribution, the continental shelf and upper slope of the north and eastern Atlantic. It is possible that O. paradoxus is continuously distributed along the north-eastern Atlantic floor, deeper than presently known. Alternatively, separate slope and ridge populations may exist