884 resultados para Standard and Eurocode design fire curves


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This thesis aims to give a general view of pavement types all over the world, by showing the different characteristics of each one and its different life steps starting from construction, passing by maintenance and arriving until recycling phase. The flexible pavement took the main part of this work because it has been used in the last part of this thesis to design a project of a rural road. This project is located in the province of Bologna-Italy (‘Comune di Argelato’, 26 km in the north of Bologna), and has 5677, 81 m of length. A pavement design was made using the program BISAR 3.0 and a fatigue life study was made, also, in order to estimate the number of loads (in terms of heavy vehicles axle) to cause road’s failure . An alignment design was made for this project and a safety study was established in order to check if the available sight distance at curves respects the safety norms or not, by comparing it to the stopping sight distance. Different technical sheets are demonstrated and several cases are discussed in order to clarify the main design principles and underline the main hazardous cases to be avoided especially at intersection. This latter, its type’s choice depends on several factors in order to make the suitable design according to the environmental data. At this part of the road, the safety is a primordial point due to the high accident rate in this zone. For this reason, different safety aspects are discussed especially at roundabouts, signalized intersections, and also some other common intersection types. The design and the safety norms are taken with reference to AASHTO (American Association of State Highway and Transportation Officials), ACT (Transportation Association of Canada), and also according to Italian norms (Decreto Ministeriale delle Starde).

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This paper presents the capabilities of a Space-Based Space Surveillance (SBSS) demonstration mission for Space Surveillance and Tracking (SST) based on a micro-satellite platform. The results have been produced in the frame of ESA’s "Assessment Study for Space Based Space Surveillance Demonstration Mission" performed by the Airbus Defence and Space consortium. The assessment of SBSS in an SST system architecture has shown that both an operational SBSS and also already a well- designed space-based demonstrator can provide substantial performance in terms of surveillance and tracking of beyond-LEO objects. Especially the early deployment of a demonstrator, possible by using standard equipment, could boost initial operating capability and create a self-maintained object catalogue. Furthermore, unique statistical information about small-size LEO debris (mm size) can be collected in-situ. Unlike classical technology demonstration missions, the primary goal is the demonstration and optimisation of the functional elements in a complex end-to-end chain (mission planning, observation strategies, data acquisition, processing, etc.) until the final products can be offered to the users and with low technological effort and risk. The SBSS system concept takes the ESA SST System Requirements into account and aims at fulfilling SST core requirements in a stand-alone manner. Additionally, requirements for detection and characterisation of small-sizedLEO debris are considered. The paper presents details of the system concept, candidate micro-satellite platforms, the instrument design and the operational modes. Note that the detailed results of performance simulations for space debris coverage and cataloguing accuracy are presented in a separate paper “Capability of a Space-based Space Surveillance System to Detect and Track Objects in GEO, MEO and LEO Orbits” by J. Silha (AIUB) et al., IAC-14, A6, 1.1x25640.

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Improving energy efficiency is an unarguable emergent issue in developing economies and an energy efficiency standard and labeling program is an ideal mechanism to achieve this target. However, there is concern regarding whether the consumers will choose the highly energy efficient appliances because of its high price in consequence of the high cost. This paper estimates how the consumer responds to introduction of the energy efficiency standard and labeling program in China. To quantify evaluation by consumers, we estimated their consumer surplus and the benefits of products based on the estimated parameters of demand function. We found the following points. First, evaluation of energy efficiency labeling by the consumer is not monotonically correlated with the number of grades. The highest efficiency label (Label 1) is not evaluated to be no less higher than labels 2 and 3, and is sometimes lower than the least energy efficient label (Label UI). This goes against the design of policy intervention. Second, several governmental policies affects in mixed directions: the subsidies for energy saving policies to the highest degree of the labels contribute to expanding consumer welfare as the program was designed. However, the replacement for new appliances policies decreased the welfare.

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Henan. Luoyang; H: 5 19/32 in.; painted pottery

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With the competitive challenge facing business today, the need to keep cost down and quality up is a matter of survival. One way in which wire manufacturers can meet this challenge is to possess a thorough understanding of deformation, friction and lubrication during the wire drawing process, and therefore to make good decisions regarding the selection and application of lubricants as well as the die design. Friction, lubrication and die design during wire drawing thus become the subject of this study. Although theoretical and experimental investigations have been being carried out ever since the establishment of wire drawing technology, many problems remain unsolved. It is therefore necessary to conduct further research on traditional and fundamental subjects such as the mechanics of deformation, friction, lubrication and die design in wire drawing. Drawing experiments were carried out on an existing bull-block under different cross-sectional area reductions, different speeds and different lubricants. The instrumentation to measure drawing load and drawing speed was set up and connected to the wire drawing machine, together with a data acquisition system. A die box connected to the existing die holder for using dry soap lubricant was designed and tested. The experimental results in terms of drawing stress vs percentage area reduction curves under different drawing conditions were analysed and compared. The effects on drawing stress of friction, lubrication, drawing speed and pressure die nozzle are discussed. In order to determine the flow stress of the material during deformation, tensile tests were performed on an Instron universal test machine, using the wires drawn under different area reductions. A polynomial function is used to correlate the flow stress of the material with the plastic strain, on which a general computer program has been written to find out the coefficients of the stress-strain function. The residual lubricant film on the steel wire after drawing was examined both radially and longitudinally using an SEM and optical microscope. The lubricant film on the drawn wire was clearly observed. Therefore, the micro-analysis by SEM provides a way of friction and lubrication assessment in wire drawing.

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Once the preserve of university academics and research laboratories with high-powered and expensive computers, the power of sophisticated mathematical fire models has now arrived on the desk top of the fire safety engineer. It is a revolution made possible by parallel advances in PC technology and fire modelling software. But while the tools have proliferated, there has not been a corresponding transfer of knowledge and understanding of the discipline from expert to general user. It is a serious shortfall of which the lack of suitable engineering courses dealing with the subject is symptomatic, if not the cause. The computational vehicles to run the models and an understanding of fire dynamics are not enough to exploit these sophisticated tools. Too often, they become 'black boxes' producing magic answers in exciting three-dimensional colour graphics and client-satisfying 'virtual reality' imagery. As well as a fundamental understanding of the physics and chemistry of fire, the fire safety engineer must have at least a rudimentary understanding of the theoretical basis supporting fire models to appreciate their limitations and capabilities. The five day short course, "Principles and Practice of Fire Modelling" run by the University of Greenwich attempt to bridge the divide between the expert and the general user, providing them with the expertise they need to understand the results of mathematical fire modelling. The course and associated text book, "Mathematical Modelling of Fire Phenomena" are aimed at students and professionals with a wide and varied background, they offer a friendly guide through the unfamiliar terrain of mathematical modelling. These concepts and techniques are introduced and demonstrated in seminars. Those attending also gain experience in using the methods during "hands-on" tutorial and workshop sessions. On completion of this short course, those participating should: - be familiar with the concept of zone and field modelling; - be familiar with zone and field model assumptions; - have an understanding of the capabilities and limitations of modelling software packages for zone and field modelling; - be able to select and use the most appropriate mathematical software and demonstrate their use in compartment fire applications; and - be able to interpret model predictions. The result is that the fire safety engineer is empowered to realise the full value of mathematical models to help in the prediction of fire development, and to determine the consequences of fire under a variety of conditions. This in turn enables him or her to design and implement safety measures which can potentially control, or at the very least reduce the impact of fire.

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In this article, we take a close look at the literacy demands of one task from the ‘Marvellous Micro-organisms Stage 3 Life and Living’ Primary Connections unit (Australian Academy of Science, 2005). One lesson from the unit, ‘Exploring Bread’, (pp 4-8) asks students to ‘use bread labels to locate ingredient information and synthesise understanding of bread ingredients’. We draw upon a framework offered by the New London Group (2000), that of linguistic, visual and spatial design, to consider in more detail three bread wrappers and from there the complex literacies that students need to interrelate to undertake the required task. Our findings are that although bread wrappers are an example of an everyday science text, their linguistic, visual and spatial designs and their interrelationship are not trivial. We conclude by reinforcing the need for teachers of science to also consider how the complex design elements of everyday science texts and their interrelated literacies are made visible through instructional practice.

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The topic of designers’ knowledge and how they conduct design process has been widely investigated in design research. Understanding theoretical and experiential knowledge in design has involved recognition of the importance of designers’ experience of experiencing, seeing, and absorbing ideas from the world as points of reference (or precedents) that are consulted whenever a design problem arises (Lawson, 2004). Hence, various types of design knowledge have been categorized (Lawson, 2004), and the nature of design knowledge continues to be studied (Cross, 2006); nevertheless, the study of the experiential aspects embedded in design knowledge is a topic not fully addressed. In particular there has been little emphasis on the investigation of the ways in which designers’ individual experience influences different types of design tasks. This research focuses on the investigation of the ways in which designers inform a usability design process. It aims to understand how designers design product usability, what informs their process, and the role their individual experience (and episodic knowledge) plays within the design process. This paper introduces initial outcomes from an empirical study involving observation of a design task that emphasized usability issues. It discusses the experiential knowledge observed in the visual representations (sketches) produced by designers as part of the design tasks. Through the use of visuals as means to represent experiential knowledge, this paper presents initial research outcomes to demonstrate how designers’ individual experience is integrated into design tasks and communicated within the design process. Initial outcomes demonstrate the influence of designers’ experience in the design of product usability. It is expected that outcomes will help identify the causal relationships between experience, context of use, and product usability, which will contribute to enhance our understanding about the design of user-product interactions.

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Experience underlies all kinds of human knowledge and determines how people interact with products and environments. It also influences designers’ knowledge and their design process. An issue not fully addressed in current literature is about the way in which designers’ individual experience influences design tasks. This paper presents two qualitative design case studies that involve experiments employing collaborative design approaches. Case study one focuses on product usability and case study two, sustainable design. Both studies applied an empirical approach; data collected consisted of sketches and audio- and video-recordings. The studies share a common research approach that opens the discussion about designers’ interactions; the way those interactions reveal knowledge and experience, the influence of these interactions upon the design process and approach to design tasks. This paper will present the correlations and discrepancies between these two case studies and the collaborative design approach used in each study, outlining future research endeavors.

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People have adopted various formats of media such as graphics, photo and text (nickname) in order to represent themselves when communicate with others online. Avatar is known as a visual form representing a user oneself and one's identity wished. Its form can vary from a two-dimensional model to a three-dimensional model, and can be visualised with various visual forms and styles. In general, two-dimensional images including an animated image are used in online forum communities and live chat software; while three-dimensional models are often used in computer games. Avatar design is often regarded as a graphic designer's visual image creation or a user's output based on one's personal preference, yet it often causes the avatar design having no consideration of its practical visual design and users' interactive communication experience aspects. This paper will review various types and styles of avatar and discuss about avatar design from visual design and online user experience perspectives. It aims to raise a design discourse in avatar design and build up a well-articulated set of design principles for effective avatar design.

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Surveillance for invasive non-indigenous species (NIS) is an integral part of a quarantine system. Estimating the efficiency of a surveillance strategy relies on many uncertain parameters estimated by experts, such as the efficiency of its components in face of the specific NIS, the ability of the NIS to inhabit different environments, and so on. Due to the importance of detecting an invasive NIS within a critical period of time, it is crucial that these uncertainties be accounted for in the design of the surveillance system. We formulate a detection model that takes into account, in addition to structured sampling for incursive NIS, incidental detection by untrained workers. We use info-gap theory for satisficing (not minimizing) the probability of detection, while at the same time maximizing the robustness to uncertainty. We demonstrate the trade-off between robustness to uncertainty, and an increase in the required probability of detection. An empirical example based on the detection of Pheidole megacephala on Barrow Island demonstrates the use of info-gap analysis to select a surveillance strategy.

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Mainstream business process modelling techniques promote a design paradigm wherein the activities to be performed within a case, together with their usual execution order, form the backbone of a process model, on top of which other aspects are anchored. This paradigm, while eective in standardised and production-oriented domains, shows some limitations when confronted with processes where case-by-case variations and exceptions are the norm. In this thesis we develop the idea that the eective design of exible process models calls for an alternative modelling paradigm, one in which process models are modularised along key business objects, rather than along activity decompositions. The research follows a design science method, starting from the formulation of a research problem expressed in terms of requirements, and culminating in a set of artifacts that have been devised to satisfy these requirements. The main contributions of the thesis are: (i) a meta-model for object-centric process modelling incorporating constructs for capturing exible processes; (ii) a transformation from this meta-model to an existing activity-centric process modelling language, namely YAWL, showing the relation between object-centric and activity-centric process modelling approaches; and (iii) a Coloured Petri Net that captures the semantics of the proposed meta-model. The meta-model has been evaluated using a framework consisting of a set of work ow patterns. Moreover, the meta-model has been embodied in a modelling tool that has been used to capture two industrial scenarios.

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The rhetoric of the pedagogic discourses of landscape architectural students and interior design students is described as part of a doctoral study undertaken to document practices and orientations prior to cross-disciplinary collaboration. We draw on the theoretical framework of Basil Bernstein, an educational sociologist, and the rhetorical method of Kenneth Burke, a literary dramatist, to study the grammars of ‘landscape’ representation employed within these disciplinary examples. We investigate how prepared final year students are for working in a cross-disciplinary manner. The discursive interactions of their work, as illustrated by four examples of drawn images and written text, are described. Our findings suggest that we need to concern ourselves aspects of our pedagogic discourse that brings uniqueness and value to our disciplines ,as well as that shared discourses between disciplines.