Improved Venting for Flammability Limit Testing Using ASTM E681 Apparatus

The literature on the determination of flammability limits was reviewed and experts on the ASTM E681 standard were interviewed to identify new means of improving the reproducibility of the ASTM E681 test. Venting was identified as a variable of flammability limits not yet addressed. Limitations of the current system for sealing and venting (a rubber stopper) were identified and addressed by the development of a custom burst disc. The burst disc was evaluated for its ability to hold and maintain a vacuum, its ability to vent at pressures of interest, and for its venting phenomena. The burst disc was deemed to be a satisfactory alternative to the rubber stopper and is recommended to be included in the ASTM E681 standard.

Posidonia oceanica (L.) Delile in its westernmost biogeographical limit (northwestern Alboran Sea): Meadows characterisation, phenology and flowering events

Posidonia oceanica is a Mediterranean endemic seagrass species that forms meadows covering ca. 2.5–4.5 millions of hectares, representing ca.25 % of the infralittoral and shallow circalittoral (down to 50m) bottoms of the Mediterranean. This seagrass is considered a habitat-engineer species and provides an elevated number of ecosystem services. In addition the Marine Strategy Framework Directive (MSFD, 2008/56/EC) includes seagrass like elements to evaluate the “Good Environmental Status” of the European coasts. Information about their phenological characteristic and structure of the meadows is needed for indicator estimations in order to establish their conservation status. The studied meadows are located in the westernmost limit of the P. oceanica distribution (North-western Alboran Sea) in the vecinity of the Strait of Gibraltar, an Atlantic-Mediterranean water transition area. Four sites were selected from East to West: Paraje Natural de Acantilados de Maro-Cerro Gordo (hereafter Maro), Special Area of Conservation “Calahonda” (hereafter Calahonda), Site of Community Importance Estepona (hereafter Estepona) and Punta Chullera (hereafter Chullera) where P. oceanica present their westernmost meadows. Phenological data were recorded from mid November to mid December in P. oceanica patches located at 2 – 3 m depth. At each site three types of patches (patch area <1m2, small patches; 1-2 m2, medium patches and >2 m2, large patches) were sampled. At each patch and site, 3 quadrants of 45 x 45 cm were sampled for shoot and inflorescences density measurements. In each quadrant, 10 random shoots were sampled for shoot morphology (shoot height and number of leaves). Shoot and inflorescences densities were standardized to squared meters. All the studied P. oceanica meadows develop on rocks and they present a fragmented structure with a coverage ranging between ca. 45% in Calahonda and Estepona and ca. 31% in Maro. The meadows of Chullera are reduced to a few small - medium patches with areas ranging between 0.5-1.5 m2 (Fig. 1). The meadows of Chullera and Estepona presented similar values of shoot density (ca. 752 – 662 shoots m-2, respectively) and leaf height (ca. 25 cm). Similarly, the Calahonda and Maro meadows also showed similar values of shoot density (ca. 510 – 550 shoots m-2, respectively) but displaying lower values than those of sites located closer to the Strait of Gibraltar. Regarding patch sizes and leaf height, the longest leaves (ca. 25 cm) were found in medium and large patches, but the number of leaves per shoot were higher in the small and the medium size patches (ca. 6.3 leaves per shoot). Flowering was only detected at the Calahonda meadows with maximum values of ca. 330 inflorescences m-2 (115.2 ± 98.2 inflorescences m-2, n= 9; mean ± SD) (Fig.1). Inflorescence density was not significant different among patches of different sizes. In the Alboran Sea and unlike the studied meadows, extensive beds of P. oceanica occur at the National Park of Cabo de Gata (northeastern Alboran Sea), but from east to west (Strait of Gibraltar), meadows are gradually fragmenting and their depth range decrease from 30m to 2m depth between Cabo de Gata and Chullera, respectively. Probably, the Atlantic influence and the characteristic oceanographic conditions of the Alboran Sea (i.e., higher turbidity, higher water turbulence) represent a developmental limiting factor for P. oceanica at higher depths. Similarities between the meadows located closer to Strait of Gibraltar (Chullera and Estepona) were detected as well as between those more distant (Calahonda and Maro). The first ones showed higher values of shoot densities and leaf heights than the formers, which could be relating to the higher hydrodynamic exposure found at Chullera and Estepona meadows. Regarding flowering events, sexual reproduction in P. oceanica is not common in different locations of the Mediterranean Sea. The available information seems to indicate that flowering represent an irregular event and it is related to high seawater temperature. In fact, the flowering episodes that occurred in Calahonda in November 2015, match with the warmest year ever recorded. This is the third flowering event registered in these meadows located close to the westernmost distributional limit of P. oceanica (Málaga, Alboran Sea), which could indicates that these meadows presents a healthy status. Furthermore, the absence of significant differences in relation to inflorescence density between patches of different sizes may be indicating that the fragmentation does not necessarily influence on the flowering of this seagrass species.

On a Limit of Perturbed Conservation Laws with Diffusion and Non-Positive Dispersion

We consider a conservation law perturbed by a linear diffusion and a general form of non-positive dispersion. We prove the convergence of the corresponding solution to the entropy weak solution of the hyperbolic conservation law.

Determination of preventive maintenance lead time using hybrid analysis

The time for conducting Preventive Maintenance (PM) on an asset is often determined using a predefined alarm limit based on trends of a hazard function. In this paper, the authors propose using both hazard and reliability functions to improve the accuracy of the prediction particularly when the failure characteristic of the asset whole life is modelled using different failure distributions for the different stages of the life of the asset. The proposed method is validated using simulations and case studies.

Condensed phase combustion travelling waves with sequential exothermic or endothermic reactions

The one-dimensional propagation of a combustion wave through a premixed solid fuel for two-stage kinetics is studied. We re-examine the analysis of a single reaction travelling-wave and extend it to the case of two-stage reactions. We derive an expression for the travelling wave speed in the limit of large activation energy for both reactions. The analysis shows that when both reactions are exothermic, the wave structure is similar to the single reaction case. However, when the second reaction is endothermic, the wave structure can be significantly different from single reaction case. In particular, as might be expected, a travelling wave does not necessarily exist in this case. We establish conditions in the limiting large activation energy limit for the non-existence, and for monotonicity of the temperature profile in the travelling wave.

On the zeros of the Abelian integrals for a class of Liénard systems

A planar polynomial differential system has a finite number of limit cycles. However, finding the upper bound of the number of limit cycles is an open problem for the general nonlinear dynamical systems. In this paper, we investigated a class of Liénard systems of the form x'=y, y'=f(x)+y g(x) with deg f=5 and deg g=4. We proved that the related elliptic integrals of the Liénard systems have at most three zeros including multiple zeros, which implies that the number of limit cycles bifurcated from the periodic orbits of the unperturbed system is less than or equal to 3.

Systemic racism: the hidden barrier to educational success for Indigenous school students

Explanations for poor educational experiences and results for Australian Indigenous school students have, to a great extent, focused on intended or conscious acts or omissions. This paper adopts an analysis based on the legislation prohibiting indirect racial discrimination. Using the elements of the legislation and case law it argues that apparently benign and race-neutral policies and practices may unwittingly be having an adverse impact on Indigenous students' education. These practices or policies include the building blocks of learning, a Eurocentric school culture. Standard English as the language of assessment, legislation to limit schools' legal liability, and teachers' promotions.

Artists, audience and participations

We spent a fare amount of time thinking and debating where to draw the line between what is and what is not single-screen-based interactive media. This really is a tricky category. I would like to use this opportunity to raise certain issues about this very new category introduced this year to ifva. First of all, what do we mean by "interactive" media? If we conceptually or philosophically try to describe it, almost every artifact (not only those who are intended as a piece of art) can be perceived as "interactive" media as soon as one sees/ recognises it and begins interacting with it physically and/or mentally. What about when we limit this to computer related media? This certainly limits the scope, but well, it is becoming increasinly difficult to find art and design that are considered innovative without the use of computer. the term "single-screen" certainly makes it more specific, but as we saw from a range of works submitted to this category, people do come up with various interpretations to it. Some simply submitted work that can be viewed with computer screen, which didn't allow much user participation, while others provided various degrees of user/audience participation. What does "singel-screen-based interactive media" mean?

Electronic tendering: an industry perspective

The construction industry is categorised as being an information-intensive industry and described as one of the most important industries in any developed country, facing a period of rapid and unparalleled change (Industry Science Resources 1999) (Love P.E.D., Tucker S.N. et al. 1996). Project communications are becoming increasingly complex, with a growing need and fundamental drive to collaborate electronically at project level and beyond (Olesen K. and Myers M.D. 1999; Thorpe T. and Mead S. 2001; CITE 2003). Yet, the industry is also identified as having a considerable lack of knowledge and awareness about innovative information and communication technology (ICT) and web-based communication processes, systems and solutions which may prove beneficial in the procurement, delivery and life cycle of projects (NSW Government 1998; Kajewski S. and Weippert A. 2000). The Internet has debatably revolutionised the way in which information is stored, exchanged and viewed, opening new avenues for business, which only a decade ago were deemed almost inconceivable (DCITA 1998; IIB 2002). In an attempt to put these ‘new avenues of business’ into perspective, this report provides an overall ‘snapshot’ of current public and private construction industry sector opportunities and practices in the implementation and application of web-based ICT tools, systems and processes (e-Uptake). Research found that even with a reserved uptake, the construction industry and its participating organisations are making concerted efforts (fortunately with positive results) in taking up innovative forms of doing business via the internet, including e-Tendering (making it possible to manage the entire tender letting process electronically and online) (Anumba C.J. and Ruikar K. 2002; ITCBP 2003). Furthermore, Government (often a key client within the construction industry),and with its increased tendency to transact its business electronically, undoubtedly has an effect on how various private industry consultants, contractors, suppliers, etc. do business (Murray M. 2003) – by offering a wide range of (current and anticipated) e-facilities / services, including e-Tendering (Ecommerce 2002). Overall, doing business electronically is found to have a profound impact on the way today’s construction businesses operate - streamlining existing processes, with the growth in innovative tools, such as e-Tender, offering the construction industry new responsibilities and opportunities for all parties involved (ITCBP 2003). It is therefore important that these opportunities should be accessible to as many construction industry businesses as possible (The Construction Confederation 2001). Historically, there is a considerable exchange of information between various parties during a tendering process, where accuracy and efficiency of documentation is critical. Traditionally this process is either paper-based (involving large volumes of supporting tender documentation), or via a number of stand-alone, non-compatible computer systems, usually costly to both the client and contractor. As such, having a standard electronic exchange format that allows all parties involved in an electronic tender process to access one system only via the Internet, saves both time and money, eliminates transcription errors and increases speed of bid analysis (The Construction Confederation 2001). Supporting this research project’s aims and objectives, researchers set to determine today’s construction industry ‘current state-of-play’ in relation to e-Tendering opportunities. The report also provides brief introductions to several Australian and International e-Tender systems identified during this investigation. e-Tendering, in its simplest form, is described as the electronic publishing, communicating, accessing, receiving and submitting of all tender related information and documentation via the internet, thereby replacing the traditional paper-based tender processes, and achieving a more efficient and effective business process for all parties involved (NT Governement 2000; NT Government 2000; NSW Department of Commerce 2003; NSW Government 2003). Although most of the e-Tender websites investigated at the time, maintain their tendering processes and capabilities are ‘electronic’, research shows these ‘eTendering’ systems vary from being reasonably advanced to more ‘basic’ electronic tender notification and archiving services for various industry sectors. Research also indicates an e-Tender system should have a number of basic features and capabilities, including: • All tender documentation to be distributed via a secure web-based tender system – thereby avoiding the need for collating paperwork and couriers. • The client/purchaser should be able to upload a notice and/or invitation to tender onto the system. • Notification is sent out electronically (usually via email) for suppliers to download the information and return their responses electronically (online). • During the tender period, updates and queries are exchanged through the same e-Tender system. • The client/purchaser should only be able to access the tenders after the deadline has passed. • All tender related information is held in a central database, which should be easily searchable and fully audited, with all activities recorded. • It is essential that tender documents are not read or submitted by unauthorised parties. • Users of the e-Tender system are to be properly identified and registered via controlled access. In simple terms, security has to be as good as if not better than a manual tender process. Data is to be encrypted and users authenticated by means such as digital signatures, electronic certificates or smartcards. • All parties must be assured that no 'undetected' alterations can be made to any tender. • The tenderer should be able to amend the bid right up to the deadline – whilst the client/purchaser cannot obtain access until the submission deadline has passed. • The e-Tender system may also include features such as a database of service providers with spreadsheet-based pricing schedules, which can make it easier for a potential tenderer to electronically prepare and analyse a tender. Research indicates the efficiency of an e-Tender process is well supported internationally, with a significant number, yet similar, e-Tender benefits identified during this investigation. Both construction industry and Government participants generally agree that the implementation of an automated e-Tendering process or system enhances the overall quality, timeliness and cost-effectiveness of a tender process, and provides a more streamlined method of receiving, managing, and submitting tender documents than the traditional paper-based process. On the other hand, whilst there are undoubtedly many more barriers challenging the successful implementation and adoption of an e-Tendering system or process, researchers have also identified a range of challenges and perceptions that seem to hinder the uptake of this innovative approach to tendering electronically. A central concern seems to be that of security - when industry organisations have to use the Internet for electronic information transfer. As a result, when it comes to e-Tendering, industry participants insist these innovative tendering systems are developed to ensure the utmost security and integrity. Finally, if Australian organisations continue to explore the competitive ‘dynamics’ of the construction industry, without realising the current and future, trends and benefits of adopting innovative processes, such as e-Tendering, it will limit their globalising opportunities to expand into overseas markets and allow the continuation of international firms successfully entering local markets. As such, researchers believe increased knowledge, awareness and successful implementation of innovative systems and processes raises great expectations regarding their contribution towards ‘stimulating’ the globalisation of electronic procurement activities, and improving overall business and project performances throughout the construction industry sectors and overall marketplace (NSW Government 2002; Harty C. 2003; Murray M. 2003; Pietroforte R. 2003). Achieving the successful integration of an innovative e-Tender solution with an existing / traditional process can be a complex, and if not done correctly, could lead to failure (Bourn J. 2002).

Loading applied on prosthetic knee of transfemoral amputee: comparison of inverse dynamics and direct measurements

Inverse dynamics is the most comprehensive method that gives access to the net joint forces and moments during walking. However it is based on assumptions (i.e., rigid segments linked by ideal joints) and it is known to be sensitive to the input data (e.g., kinematic derivatives, positions of joint centres and centre of pressure, inertial parameters). Alternatively, transducers can be used to measure directly the load applied on the residuum of transfemoral amputees. So, the purpose of this study was to compare the forces and moments applied on a prosthetic knee measured directly with the ones calculated by three inverse dynamics computations - corresponding to 3 and 2 segments, and « ground reaction vector technique » - during the gait of one patient. The maximum RMSEs between the estimated and directly measured forces (i.e., 56 N) and moment (i.e., 5 N.m) were relatively small. However the dynamic outcomes of the prosthetic components (i.e., absorption of the foot, friction and limit stop of the knee) were only partially assessed with inverse dynamic methods.

Site survey and analysis of highway trucks overloading status quo in Anhui

In 2004, with the increasing overloading restriction requirements of society in Anhui, a provincial comprehensive overloading transportation survey has been developed to take evaluations on overloading actuality and enforcement efficiency with the support of the World Bank. A total of six site surveys were conducted at Hefei, Fuyang, Luan, Wuhu, Huainan and Huangshan Areas with four main contents respectively: traffic volume, axle load, freight information and registration information. Via statistical analysis on the survey data, conclusions were gained that: vehicle overloading are very universal and serious problems at arterial highways in Anhui now. The traffic loads have far exceeded the designed endure capacity of highways and have caused prevalent premature pavement damage, especially for rigid pavement. The overloading trucks are unimpeded engaged in highway freight transportation actually due to the disordered overloading enforcement strategies and the deficient inspecting technologies.

Village green

For a communal garden in Copenhagen, Stig L. Andersson uses grasses of varying texture and height, creating a new view or spatial experience from every angle. The idea of vegetation texture being an important constituent of planting design is pervasive. Gardening books tell aspiring designers that "colour, texture and form" are the central aspects of planting arrangements. While these elements contribute to this language, they have tended to limit the language of planting to a singular, two dimensional paradigm, where planting is designed in static elevation. This has developed from a perennial-border approach demonstrated by the early 20th century garden designer Gertrude Jekyll, where the viewer is parallel to the bed, and the planting is layered to address this view. If one were to characterise the difference between a garden design and a landscape architectural approach, the latter would seem self-conscious in its use of space, movement and vision.

The interactions of consumption characteristics on social norms

Purpose: An extended Theory of Planned Behavior (TPB) model tests how customer loyalty intentions may relate to subjective and descriptive norms. The study further determines whether consumption characteristics – product enjoyment and importance – moderate norms-loyalty relationships.----- Methodology: Using a two-study approach focusing on youth, an Australian study (n = 244) first augmented TPB with descriptive norm. A Singapore study (n = 415) followed up with how consumption characteristics might moderate norms-loyalty relationships. With both studies, linear regressions tested the relationships among the variables.----- Findings: Extending TPB with descriptive norm improved TPB’s predictive ability across studies. Further, product enjoyment and importance moderated the norms-loyalty relationships differently. Subjective norm related to loyalty intentions significantly with high enjoyment, whereas descriptive norm was significant with low enjoyment. Only subjective norm was significant with low importance.----- Research limitations: Single-item variables, self-reported questionnaires on intended rather than actual behavior, and not controlling for cultural differences between the two samples limit generalizablity.----- Practical implications: The significance of both norms suggests that mobile firms should reach youth through their peers. With youth, social pressure may be influential particularly with hedonic products. However, the different moderations of product enjoyment and importance imply that a blanket marketing strategy targeting youth may not work.----- Originality/Value: This study extends academic knowledge on the relationships between norms and customer loyalty, particularly with consumption characteristics as moderators. The findings highlight the importance of considering different norms with consumer behavior. The study should help mobile firms understand how social influences impact customer loyalty.

Living walls - a way to green the built environment

Actions Towards Sustainable Outcomes Environmental Issues/Principal Impacts The increasing urbanisation of cities brings with it several detrimental consequences, such as: • Significant energy use for heating and cooling many more buildings has led to urban heat islands and increased greenhouse gas emissions. • Increased amount of hard surfaces, which not only contributes to higher temperatures in cities, but also to increased stormwater runoff. • Degraded air quality and noise. • Health and general well-being of people is frequently compromised, by inadequate indoor air quality. • Reduced urban biodiversity. Basic Strategies In many design situations, boundaries and constraints limit the application of cutting EDGe actions. In these circumstances, designers should at least consider the following: • Living walls are an emerging technology, and many Australian examples function more as internal feature walls. However,as understanding of the benefits and construction of living walls develops this technology could be part of an exterior facade that enhances a building’s thermal performance. • Living walls should be designed to function with an irrigation system using non-potable water. Cutting EDGe Strategies • Living walls can be part of a design strategy that effectively improves the thermal performance of a building, thereby contributing to lower energy use and greenhouse gas emissions. • Including living walls in the initial stages of design would provide greater flexibility to the design, especially of the facade, structural supports, mechanical ventilation and watering systems, thus lowering costs. • Designing a building with an early understanding of living walls can greatly reduce maintenance costs. • Including plant species and planting media that would be able to remove air impurities could contribute to improved indoor air quality, workplace productivity and well-being. Synergies and References • Living walls are a key research topic at the Centre for Subtropical Design, Queensland University of Technology: http://www.subtropicaldesign.bee.qut.edu.au • BEDP Environment Design Guide: DES 53: Roof and Facade Gardens • BEDP Environment Design Guide: GEN 4: Positive Development – Designing for Net Positive Impacts (see green scaffolding and green space frame walls). • Green Roofs Australia: www.greenroofs.wordpress.com • Green Roofs for Healthy Cities USA: www.greenroofs.org