Caracterização isoenzimática de pupunha (Bactris gasipaes).

Resumo 23

Impacto visual dos estaleiros de construção nos centros urbanos

Este artigo pretende abordar os diversos impactos que os estaleiros de construção provocam na sua área de implantação e imediações. Analise-se de forma mais pormenorizada o impacto visual que estes têm nos meios urbanos e em particular nos centros históricos, apresentando alguns casos com impacto marcadamente negativo e outros onde a solução pretende e consegue enquadrar de forma harmoniosa o estaleiro com a envolvente. São enumeradas e sugeridas formas de minimizar este impacto

Disjunctive shared information between ontology concepts: application to Gene Ontology

<p>Abstract</p> <p>Background</p> <p>The large-scale effort in developing, maintaining and making biomedical ontologies available motivates the application of similarity measures to compare ontology concepts or, by extension, the entities described therein. A common approach, known as semantic similarity, compares ontology concepts through the information content they share in the ontology. However, different disjunctive ancestors in the ontology are frequently neglected, or not properly explored, by semantic similarity measures.</p> <p>Results</p> <p>This paper proposes a novel method, dubbed DiShIn, that effectively exploits the multiple inheritance relationships present in many biomedical ontologies. DiShIn calculates the shared information content of two ontology concepts, based on the information content of the disjunctive common ancestors of the concepts being compared. DiShIn identifies these disjunctive ancestors through the number of distinct paths from the concepts to their common ancestors.</p> <p>Conclusions</p> <p>DiShIn was applied to Gene Ontology and its performance was evaluated against state-of-the-art measures using CESSM, a publicly available evaluation platform of protein similarity measures. By modifying the way traditional semantic similarity measures calculate the shared information content, DiShIn was able to obtain a statistically significant higher correlation between semantic and sequence similarity. Moreover, the incorporation of DiShIn in existing applications that exploit multiple inheritance would reduce their execution time.</p

As consequências do incumprimento dos prazos para a competitividade da indústria de construção : razões para os atrasos

Este artigo pretende divulgar o estudo que tem decorrido na Universidade do Minho sobre a problemática dos incumprimentos dos prazos de construção. Numa primeira fase centrou-se na identificação das causas dos atrasos dos projectos de construção, nos métodos da sua resolução e aspectos afins, numa segunda fase procedeu-se à elaboração e implementação de um inquérito às partes envolvidas nas actividades de construção

Using linear model for learning curve effect on highrise floor construction

The evolution of repetitive scheduling methods led to the introduction of the learning concept in construction planning. It is common knowledge that performing the same activity repeatedly, and in the same conditions, takes less and less time as the activity is repeated (Gates and Scarpa, 1972). This phenomenon is clear in many construction activities and is known as learning experience or learning effect. The increase in productivity is mainly due to the increasing knowledge acquired by work repetition. Graphic representation is through a learning curve that admits duration decreases as the activity is repeated, according to a predictable and constant learning rate. The Linear Model of logarithmic coordinates (log10Y 5 log10A – nlog10X) was applied to two repetitive construction processes, frequently used in Portuguese construction. The intent was to examine its applicability and efficiency in predicting future performances, and the interest in incorporating the model in new planning methodologies for repetitive construction. In both cases, learning processes were created

Método das curvas de equilíbrio no planeamento da construção repetitiva em altura

A abordagem do planeamento da construção repetitiva iniciou-se com os métodos tradicionais de programação. Porém, dadas as suas limitações no tratamento do problema desenvolveram-se métodos específicos para este tipo de construção, e mais recentemente introduziu-se o conceito de aprendizagem. Neste trabalho apresenta-se um novo método de programação dos trabalhos repetitivos, dotado dos atributos das metodologias tradicionais e das vantagens que resultam da utilização de métodos específicos na programação daquele tipo de trabalhos e que inclui a consideração do efeito da aprendizagem

Reasons for the lack of competitiveness of the portuguese construction industry

The last few years have confirmed what was mostly feared: Portuguese construction industry suffers from a chronic disease - the lack of competitiveness. Symptoms have long been recognised in several construction projects: frequent delays, cost overruns, deficient safety, absent quality. The authors have been carrying out several studies whose aiming at are clarify reasons for the lack of competitiveness of national construction industry on the four items mentioned above. This paper occurs mainly about the aims of PhD` survey about construction delays. It has the following mains components: (1) to research and analysis bibliography and establish a common set of causes and background reasons for the problem; (2) to inquire to Portuguese construction stakeholders on the causes and background reasons for project delays following from their experience in recent projects; (3) to establish possible paths to solve the problem. The survey results appear to confirm the original list of causes for delays of the study. The mains reasons are related with designer problems, poor productivity, procurement system, overly optimistic planning, and frequent change orders during construction and so on. Thereafter, the paper will seek what could possibly be done and from which parties, in order to correct the above problems and improve construction competitiveness. The most highly ranked on a scale of relevance by stakeholders were implementation a national database with the quantity works list for different construction projects, a more appropriate and efficient organizational systems within design teams and a need for greater care on the part of the owners when they prepare their schedules and preliminary programmes.Science and Technology Foundation, in Portuguese - Project SAPIENS Nº 4762 "Reasons for the lack of accomplishment of schedule, costs and safety objectives in construction".LEONARDO DA VINCI - Community Vocational Training Action Programme Second, Phase 2000-2006 - Project PL/04/B/P/PP/-174 417 "Recognition of needs and creation of professional training in the area of preparation and management of infrastructure construction projects financed by the European Union"

Microscopic mechanism for mechanical polishing of diamond (110) surfaces

Mechanically induced degradation of diamond, as occurs during polishing, is studied using total--energy pseudopotential calculations. The strong asymmetry in the rate of polishing between different directions on the diamond (110) surface is explained in terms of an atomistic mechanism for nano--groove formation. The post--polishing surface morphology and the nature of the polishing residue predicted by this mechanism are consistent with experimental evidence.Comment: 4 pages, 5 figure

Advances in materials science and engineering assessment of gamma radiation hazards related to geologic materials: comparison of results by field gamma spectrometry and laboratory methods

Geologic materials are a potential source of external gamma radiation in buildings due to the presence of radioisotopes (K-40 and isotopes from U and Th decay families). The contents of these radioisotopes can be evaluated by laboratory analyses that require the extraction of samples, with associated financial and time constraints, and it is also difficult to perform on materials already applied in existing structures. In this work, portable gamma spectrometry results are compared with laboratory analyses in terms of radioisotopes estimations, and the activity concentration index is calculated from them (which assess the conjoint contribution of the different radioisotopes to the external gamma radiation). The studied objects are rocks and their "in situ" weathering products. The results obtained indicate that despite several problems posed by field measurements with portable gamma spectrometry, namely, in terms of the geometric characteristics of the objects measured, this technique has the potential to identify materials with different hazard levels related to external gamma radiation.The Lab2PT-Landscapes, Heritage and Territory laboratory-AUR/04509 is supported by the Portuguese "Fundacao para a Ciencia e a Tecnologia" (Portuguese funds and where applicable the FEDER co-financing, in the aim of the new partnership agreement PT2020 and COMPETE2020-POCI 01 0145 FEDER 007528). The University Institute of Geology of the University of A Coruna (Spain) received support from Xunta de Galicia with funds from "Consolidacion y estructuracion de unidades de investigacion competitivas-Grupo de potencial de crecimiento" (GPC2015/024). The authors would like to thank A. Pinto, F. Dias, M. Cunha, and P. Pereira for help during the field work

Modelos de aprendizagem na construção

A importância da consideração do efeito de aprendizagem no planeamento das actividades produtivas industriais tem sido objecto de investigação abundante. Recentemente, com o reconhecimento das vantagens da consideração do fenómeno, a investigação estendeuse também ao sector da construção. No entanto, são conhecidas dificuldades de aplicação do produto dessa análise em especial no tocante ao modelo matemático a adoptar para a curva de aprendizagem. Neste trabalho, faz-se uma descrição dos modelos matemáticos mais utilizados para a modelação da aprendizagem e é apresentado um estudo que aponta para uma melhor correlação do modelo cúbico (logx, y) com a informação conhecida e para uma melhor previsão do modelo linear (logx, logy) de desempenhos futuros