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Useful Life (useful + life)
Selected AbstractsLlong Casnewydd: the Newport Ship,a Personal ViewINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 1 2004Owain T. P. Roberts The discovery of a late medieval ship on a building site at Newport (Casnewydd) in south Wales, UK, in 2002 raised public awareness of the fragility of such discoveries where they interrupt municipal building programmes. Within a tight schedule the ship remains were recovered and now await further work. The origins of the ship are unknown since the dendrochronology is as yet unmatched, though the structure indicates Scandinavian and possibly Basque influences. Artefacts indicate trading with Iberia during the first half of the 15th century. Much of the ship had been salvaged at the end of her useful life about 1467. © 2004 The Nautical Archaeology Society [source] Evaluation of trimedlure dispensers by a method based on thermal desorption coupled with gas chromatography,mass spectrometryJOURNAL OF APPLIED ENTOMOLOGY, Issue 9-10 2008C. Alfaro Abstract Knowledge about the behaviour of trimedlure (TML) dispensers is essential to ensure the efficacy of monitoring and control methods based on TML as attractant. There are several commercially available TML dispensers, and each of them has a different useful life and TML release profile. Their emission is also affected differently by environmental factors. Even the same type of dispenser sometimes shows an important variability in the TML release rate. Because of the importance of methods based on TML lures in the control of the Mediterranean fruit fly and the influence of the TML dispenser on the efficacy of these control methods, we developed a non-destructive flow-through system to measure the TML release rate. This volatile collection method (VCM) adsorbs TML vapour on a Tenax TA desorption tube, and TML is quantified by Thermal desorption coupled with gas chromatography/mass spectrometry. Two types of TML dispensers, a polymeric (Aralure) and a mesoporous (Epalure), were field aged during 3 months. The TML release rates of these dispensers were determined by both, VCM and solvent extraction method. In this study, the correlation between both measurement methods is shown. A field trial has also been carried out to correlate trap catches and TML emission of each type of tested dispenser. The VCM allows a quick and accurate evaluation of the current behaviour of commercial dispensers along their useful life. It also allows comparing the TML release rate between different dispensers. We believe that the VCM can be useful for dispenser manufacturers to determine seasonal dispenser performance before a new product is introduced in the market, and to rapidly verify TML dispenser release when field-aged dispenser efficacy is in question. Thus, it can be employed as a quality control of commercial dispensers. [source] Survival Analysis Applied to Sensory Shelf Life of Yogurts,II: Spanish FormulationsJOURNAL OF FOOD SCIENCE, Issue 7 2005Ana Salvador ABSTRACT: Sensory shelf lives of commercial Spanish yogurts stored at 10 °C were studied. Yogurts were strawberry flavored and differed in fat content (free and whole-fat) and consistency (stirred and set-style). Yogurts were tested between 0 and 90 d of storage by consumers who expressed acceptance or rejection of each sample and measured overall and attribute acceptability on a 9-point hedonic scale. Survival analysis statistics were used to estimate sensory shelf lives. Considering 25% of consumers rejecting the product, shelf lives varied from 38 to 69 d, depending on the composition, so if useful life were to be established using sensory criteria, a single shelf life for yogurt would not appear to be very appropriate. A log-linear model and a direct quantile comparison formula were introduced to analyze the effect of formulation on rejection time distributions and shelf life values, respectively. Fat-free yogurts had shorter shelf lives than whole-fat yogurts. Acceptability of yogurts measured on a 9-point hedonic scale varied less than percentage rejection over the storage times. [source] Architecture-based semantic evolution of embedded remotely controlled systemsJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 3 2003Lawrence Chung Abstract Evolution of a software system is a natural process. In most systems, evolution takes place during the maintenance phase of their life cycles. Those systems that have reached their limit in evolution have usually reached their end of useful life and may have to be replaced. However, there are systems in which evolution occurs during the operational phase of their life cycles. Such systems are designed to evolve while in use or, in other words, be adaptable. Semantically adaptable systems are of particular interest to industry as such systems often times adapt themselves to environment change with little or no intervention from their developing or maintaining organization. Since embedded systems usually have a restricted hardware configuration, it is difficult to apply the techniques developed for non-embedded systems directly to embedded systems. This paper focuses on evolution through adaptation and develops the concepts and techniques for semantic evolution in embedded systems. As the first step in the development of a software solution, architectures of software systems themselves have to be made semantically evolvable. In this paper we explore various architectural alternatives for the semantic evolution of embedded systems,these architectures are based on four different techniques that we have identified for semantic evolution in embedded systems. The development of these architectures follows the systematic process provided by the non-functional requirement (NFR) framework, which also permits the architectures to be rated in terms of their evolvability. As the field of embedded systems is vast, this paper concentrates on those embedded systems that can be remotely controlled. In this application domain the embedded system is connected to an external controller by a communication link such as ethernet, serial, radio frequency, etc., and receives commands from and sends responses to the external controller via the communication link. The architectures developed in this paper have been partly validated by applying them in a real embedded system,a test instrument used for testing cell phones. These architectures and techniques for semantic evolution in this application domain give a glimpse of what can be done in achieving semantic evolution in software-implemented systems. Copyright © 2003 John Wiley & Sons, Ltd. [source] Linear sulphonate detergents as pour point depressantsLUBRICATION SCIENCE, Issue 2 2004S. Li Abstract Oil-soluble metallic sulphonate detergents have been extensively used in automobile lubricants to keep engines clean and to extend their useful life. Calcium alkylbenzene sulphonate is widely used in the lubricant industry as a detergent. However, the authors have discovered that, uniquely, linear sulphonate detergents can play another role in lubricants, namely to depress the pour point of mineral oils. The authors have studied the relationship between the molecular structures of sulphonate detergents and pour point depression, and it has been found that, in order for a sulphonate detergent to be a pour point depressant (PPD), it must have a linear hydrocarbon tail. Other factors, such as the metal type, e.g., Ca or Mg, and the degree of overbasing, are not critical for pour point depression activity. A model is proposed to explain why sulphonate detergents with linear hydrocarbon tails can function as pour point depressants. [source] Thermal degradation of a brominated bisphenol a derivativePOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 11-12 2003M. P. Luda Abstract The thermal degradation of 2,6,2,,6,,tetrabromo-4,4,-isopropylidene-di phenol (tetrabromobisphenol A) (TBBPA) has been investigated and a mechanism for its thermal degradation is suggested. TBBPA is a comonomer widely used in epoxy and in unsaturated polyester resins to impart fire retardance. These resins find a common use in electric and electronic equipment. The presence of bromine atoms is the key factor in fire retardant activity, while on the other hand it represents an ecological problem when pyrolytic recycling is programmed at the end of the useful life of such items. However, pyrolysis is the more advantageous recycling system for thermosetting resins and thus efforts should be made to control the pyrolysis in order to avoid or minimize the development of toxics. Homolytic scission of the aromatic bromine and condensation of aromatic bromine with phenolic hydroxyl are the main processes occurring in the range 270,340°C. A large amount of charred residue is left as a consequence of condensation reactions. HBr and brominated phenols and bisphenols are the main volatile products formed. Brominated dibenzodioxins structures are included in the charred residue and not evolved in the volatile phases. Copyright © 2003 John Wiley & Sons, Ltd. [source] Methodology and model for performance and cost comparison of innovative treatment technologies at wood preserving sitesREMEDIATION, Issue 1 2001Mark L. Evans Wood preserving facilities have used a variety of compounds, including pentachlorophenol (PCP), creosote, and certain metals, to extend the useful life of wood products. Past operations and waste management practices resulted in soil and water contamination at a portion of the more than 700 wood preserving sites in the United States (EPA, 1997). Many of these sites are currently being addressed under federal, state, or voluntary cleanup programs. The U.S. Environmental Protection Agency (EPA) National Risk Management Research Laboratory (NRMRL) has responded to the need for information aimed at facilitating remediation of wood preserving sites by conducting treatability studies, issuing guidance, and preparing reports. This article presents a practical methodology and computer model for screening the performances and comparing the costs of seven innovative technologies that could be used for the treatment of contaminated soils at user-specified wood preserving sites. The model incorporates a technology screening function and a cost-estimating function developed from literature searches and vendor information solicited for this study. This article also provides background information on the derivation of various assumptions and default values used in the model, common contaminants at wood preserving sites, and recent trends in the cleanup of such sites. © 2001 John Wiley & Sons, Inc. [source] Strategic Responses to Environmental Regulation in the U.K. Automotive Sector: The European Union End-of-Life Vehicle Directive and the Porter HypothesisJOURNAL OF INDUSTRIAL ECOLOGY, Issue 4 2006Jo Crotty Summary As of 1 January 2006 all automotive OEMs (original equipment manufacturers) and component manufacturers operating within the European Union will need to comply with the End-of-Life Vehicle Directive (referred to hereafter as the EU ELV Directive). The EU ELV Directive compels all OEMs to take back and dismantle all motor vehicles for domestic use at the end of their useful lives. Each component part will then be either reused or recycled. To this end, the ultimate goal of the EU ELV Directive is that all motor vehicles for domestic use will have a reuse or recyclable content of 85% at the end of their useful lives, moving toward 95% by 2015. The burden of the EU ELV Directive falls on both the OEMs and their component manufacturers, forcing them to innovate and "design for disassembly." This being the case, it offers a unique real world example with which to test the Porter Hypothesis. Porter asserts that strict, correctly formulated environmental regulation can offer a firm secondary benefits through improved product design and the reduction of waste. This in turn allows the firm to offset the cost of compliance. Because the EU ELV Directive has been fashioned to force firms into a process of innovation and redesign, the magnitude of these so-called offsets can be judged. This article employs Rugman and Verbeke's 1998 strategic matrix of firm response to environmental regulation to examine qualitative details of the strategic response of automotive component manufacturers and OEMs in the United Kingdom to the demands of the directive to judge the volume of offsets generated. This analysis shows no support for the Porter Hypothesis and challenges the assumptions of Rugman and Verbeke's model. [source] Integrating maintenance activities and Quality Assurance in a research and development (R&D) systemQUALITY ASSURANCE JOURNAL, Issue 4 2006Debasish Basak Abstract A well-balanced maintenance program furnishes information and instructions to personnel involved in maintaining existing equipment, provides current information on the availability and location of maintenance materials, improves utilization of labor forces and increases equipment reliability. Planned and preventive maintenance procedures where components are serviced and changed when they approach the end of their useful lives can be augmented by suitable means, which continuously check vital machine functions. Quality Assurance can be seen as a management system that brings maintenance activities undertaken by all parties under control with the aim of preventing things from going wrong and costing time, effort and money to put them right. An attempt has been made to highlight the integration of maintenance activities with Quality Assurance as a whole in a research and development (R&D) system. Copyright © 2006 John Wiley & Sons, Ltd. [source] | ||||||||||