105,587 research outputs found
An analysis of the requirements traceability problem
In this paper1, we investigate and discuss the underlying nature
of the requirements traceability problem. Our work is based on
empirical studies, involving over 100 practitioners, and an
evaluation of current support. We introduce the distinction
between pre-requirements specification (pre-RS) traceability
and post-requirements specification (post-RS) traceability, to
demonstrate why an all-encompassing solution to the problem is
unlikely, and to provide a framework through which to
understand its multifaceted nature. We report how the majority
of the problems attributed to poor requirements traceability are
due to inadequate pre-RS traceability and show the fundamental
need for improvements here. In the remainder of the paper, we
present an analysis of the main barriers confronting such
improvements in practice, identify relevant areas in which
advances have been (or can be) made, and make
recommendations for research
Trends in Cardiac Pacemaker Batteries
Batteries used in Implantable cardiac pacemakers-present unique challenges to their developers and manufacturers in terms of high levels of safety and reliability. In addition, the batteries must have longevity to avoid frequent replacements. Technological advances in leads/electrodes have reduced energy requirements by two orders of magnitude. Micro-electronics advances sharply reduce internal current drain concurrently decreasing size and increasing functionality, reliability, and longevity. It is reported that about 600,000 pacemakers are implanted each year worldwide and the total number of people with various types of implanted pacemaker has already crossed 3 million. A cardiac pacemaker uses half of its battery power for cardiac stimulation and the other half for housekeeping tasks such as monitoring and data logging. The first implanted cardiac pacemaker used nickel-cadmium rechargeable battery, later on zinc-mercury battery was developed and used which lasted for over 2 years. Lithium iodine battery invented and used by Wilson Greatbatch and his team in 1972 made the real impact to implantable cardiac pacemakers. This battery lasts for about 10 years and even today is the power source for many manufacturers of cardiac pacemakers. This paper briefly reviews various developments of battery technologies since the inception of cardiac pacemaker and presents the alternative to lithium iodine battery for the near future
âFuture Bathroomâ, What to make? Or How to Make? Challenges in meeting sustainable needs.
This paper is a case study that describes a design research programme, âthe future bathroomâ, undertaken by the authors which illuminates both challenges and solutions for inclusive and sustainable design. A co-design research methodology was adopted and engaged older users and community lay researchers to help overcome the barriers of developing a comprehensive understanding of the issues related to highly personal, private and intimate activities. We adopt the term co-design to describe an approach to design that encourages both user involvement and interdisciplinary design. Our challenge has been to provide an environment where an exchange of ideas between stakeholders could take place and to foster what Manzini (1) has referred to as a âcreative communityâ. From the project emerged both insight and understanding of age related disability and bathroom use and potential design solutions to support these needs. Adopting an inclusive approach to design research we have developed flexible, durable and sustainable solutions that meet the diverse and changing needs of bathroom usage The paper discusses how sustainability in the context of inclusive design might need to consider more âwhat we should makeâ rather than âhow we should makeâ
Guidelines for the Use of Synthetic Fluid Dust Control Palliatives on Unpaved Roads
The amount of small soil particles, dust, lost from typical unpaved roads to fugitive dust is staggering. A 1 km stretch of unpaved road can contribute over 2400 kg of dust to the atmosphere (4.2 ton/mile) in a typical 3-month summer season. Road managers typically manage dust from unpaved roads with various dust-control palliatives, which are effective for up to 1 year. Synthetic fluids are a relatively new category of dust-control palliatives. Unlike the more commonly used dust-control palliatives, such as salts, engineering guidelines do not exist for the application and maintenance of synthetic fluids on unpaved roads. To fill this void, we present through this document guidelines for road design and maintenance, palliative selection, application, and care of synthetic fluid-treated roadways.Midwest Industrial Supply
United States Department of TransportationReport Documentation Page .............................................................................................. ii
Disclaimer ......................................................................................................................... iii
List of Figures .................................................................................................................... vi
Executive Summary............................................................................................................. 1
CHAPTER 1.0 â Introduction............................................................................................... 4
CHAPTER 2.0 â Background.............................................................................................. 6
Measurements of the Effectiveness of Dust Palliatives .....................................................10
CHAPTER 3.0 â Guidelines .............................................................................................. 16
Road Design and Maintenance...........................................................................................16
Palliative Selection..............................................................................................................20
Application .........................................................................................................................22
Areas Requiring Special Attention......................................................................................26
Maintenance .......................................................................................................................27
CHAPTER 4.0 â Summary................................................................................................. 31
CHAPTER 5.0 â References.............................................................................................. 3
Cooperative Longevity and Sustainable Development in a Family Farming System
This paper focuses on small holding, family farming in Southeast Spain where agricultural economic activity is predominantly organized around cooperative business models. A variety of diverse studies on the AlmerĂa agricultural and credit cooperative sector and the exploration of social-economic and eco-social indicators, in addition to economic-market indicators are presented. Each correspond to a cooperative âlogicâ that spans theoretical perspectives from the dominant economic-market model, new institutionalism, and an eco-social approach, echoing theories on collective coordination governance, and the avoidance of the âtragedy of the commonsâ. The latter is of particular importance given environmental challenges and scarce resources for agricultural activity. The cooperatives in AlmerĂa have increasingly relied on collective collaboration and coordination in order to meet social-economic and social-ecological challenges, transforming their role from that founded on a market dominant logic to that of cooperation as a coordination mechanism based on the mutual benefit of the community and environment. In turn, their ability to meet a wide range of needs and challenges of members and the community leads to their longevity. Cooperatives are able to act as both a market and non-market coordination mechanism, balancing the economic, social, and environmental dimensions, such that neither market nor non-market logics are dominant or exclusive
Annuities for an ageing world
Substantial research attention has been devoted to the pension accumulation process, whereby employees and those advising them work to accumulate funds for retirement. Until recently, less analysis has been devoted to the pension decumulation process â the process by which retirees finance their consumption during retirement. This gap has recently begun to be filled by an active group of researchers examining key aspects of the pension payout market. One of the areas of most interesting investigation has been in the area of annuities, which are financial products intended to cover the risk of retirees outliving their assets. This paper reviews and extends recent research examining the role of annuities in helping finance retirement consumption. We also examine key market and regulatory factors
Global communication part 1: the use of apparel CAD technology
Trends needed for improved communication systems, through the development of future computer-aided design technology (CAD) applications, is a theme that has received attention due to its perceived benefits in improving global supply chain efficiencies. This article discusses the developments of both 2D and 3D computer-aided design capabilities, found within global fashion supply chain relationships and environments. Major characteristics identified within the data suggest that CAD/CAM technology appears to be improving; however, evidence also suggest a plateau effect, which is accrediting forced profits towards information technology manufactures, and arguably compromising the industry's competitive advantage. Nevertheless, 2D CAD increases communication speed; whereas 3D human interaction technology is seen to be evolving slowly and questionably with limited success. The article discusses the findings and also presents the issues regarding human interaction; technology education; and individual communication enhancements using technology processes. These are still prevalent topics for the future developments of global strategy and cultural communication amalgamation
The real issues with in-ground SUDS in Scotland
The aim of this research was to produce enhanced detailing and improved operation of in-ground SUDS. Data from on-site monitoring at three filter drain and three infiltration trench systems were analysed and the results were combined with information gathered from 40 assessments of in-situ systems in Eastern Scotland. Current findings showed that almost 50% of all systems were found to be unsatisfactory and more than half of these were rated as having failed. 36% provided fair and 16%, good performance. Only one system was considered to be performing excellently. Several reasons were identified for the poor performance. The principal cause of problems was runoff from unstabilised areas or construction runoff, which was found to be affecting the systemsâ longevity. Almost 30% of all sites were affected by construction runoff. Another major problem was related to system maintenance since maintenance programs were generally not in place. This study has shown that regular maintenance is vital for the longevity of in-ground SUDS
Biomarkers of Aging: From Primitive Organisms to Man
What biological changes take place as we age? Efforts by scientists to uncover the biomarkers of aging, that is, the normal phenomena of growing old, and to separate these inevitable physiologic changes from diseases and other factors.Warns that alleged "anti-aging" medicines like growth hormone injections are unprovable given current scientific knowledge
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