4 resultados para Nitrogen Availability
em Repositório Científico do Instituto Politécnico de Lisboa - Portugal
Resumo:
In the last decades considerations about equipments' availability became an important issue, as well as its dependence on components characteristics such as reliability and maintainability. This is particularly of outstanding importance if one is dealing with high risk industrial equipments, where these factors play an important and fundamental role in risk management when safety or huge economic values are in discussion. As availability is a function of reliability, maintainability, and maintenance support activities, the main goal is to improve one or more of these factors. This paper intends to show how maintainability can influence availability and present a methodology to select the most important attributes for maintainability using a partial Multi Criteria Decision Making (pMCDM). Improvements in maintainability can be analyzed assuming it as a probability related with a restore probability density function [g(t)].
Resumo:
Four cationic ruthenium(II) complexes with the formula [Ru(eta(5)-C5H5)(PPh3)(2)](+), with L = 5-phenyl-1H-tetrazole (TzH) 1, imidazole (ImH) 2, benzo[1,2-b; 4,3-b'] dithio-phen-2-carbonitrile (Bzt) 3, and [5-(2-thiophen-2-yl)-vinyl]-thiophene-2-carbonitrile] (Tvt) 4 were prepared and characterized in view to evaluate their potentialities as antitumor agents. Studies by Circular Dichroism indicated changes in the secondary structure of ct-DNA. Changes in the tertiary structure of pBR322 plasmid DNA were also observed in gel electrophoresis experiment and the images obtained by atomic force microscopy (AFM) suggest strong interaction with pBR322 plasmid DNA; the observed decreasing of the viscosity with time indicates that the complexes do not intercalate between DNA base pairs. Compounds 1, 2, and 3 showed much higher cytotoxicity than the cisplatin against human leukaemia cancer cells (HL-60 cells).
Resumo:
We live in a changing world. At an impressive speed, every day new technological resources appear. We increasingly use the Internet to obtain and share information, and new online communication tools are emerging. Each of them encompasses new potential and creates new audiences. In recent years, we witnessed the emergence of Facebook, Twitter, YouTube and other media platforms. They have provided us with an even greater interactivity between sender and receiver, as well as generated a new sense of community. At the same time we also see the availability of content like it never happened before. We are increasingly sharing texts, videos, photos, etc. This poster intends to explore the potential of using these new online communication tools in the cultural sphere to create new audiences, to develop of a new kind of community, to provide information as well as different ways of building organizations’ memory. The transience of performing arts is accompanied by the need to counter that transience by means of documentation. This desire to ‘save’ events reaches its expression with the information archive of the different production moments as well as the opportunity to record the event and present it through, for instance, digital platforms. In this poster we intend to answer the following questions: which online communication tools are being used to engage audiences in the cultural sphere (specifically between theater companies in Lisbon)? Is there a new relationship with the public? Are online communication tools creating a new kind of community? What changes are these tools introducing in the creative process? In what way the availability of content and its archive contribute to the organization memory? Among several references, we will approach the two-way communication model that James E. Grunig & Todd T. Hunt (1984) already presented and the concept of mass self-communication of Manuel Castells (2010). Castells also tells us that we have moved from traditional media to a system of communication networks. For Scott Kirsner (2010), we have entered an era of digital creativity, where artists have the tools to do what they imagined and the public no longer wants to just consume cultural goods, but instead to have a voice and participate. The creativity process is now depending on the public choice as they wander through the screen. It is the receiver who owns an object which can be exchanged. Virtual reality has encouraged the receiver to abandon its position of passive observer and to become a participant agent, which implies a challenge to organizations: inventing new forms of interfaces. Therefore, we intend to find new and effective online tools that can be used by cultural organizations; the best way to manage them; to show how organizations can create a community with the public and how the availability of online content and its archive can contribute to the organizations’ memory.
Resumo:
This paper shows several ways to analyse the performance of a safety barrier, depending on the objective to be achieved and present a method to analyse binary components usually present on sensor systems of safety barriers. An application example of a water-based fire system is presented and the Probability of Failure on Demand (PFD) of the sensor system is determined based on the analysis of pressure switches installed in this safety barrier. The knowledge of such information will allow the determination of safety barrier’s availability.