Home About us Contact
|
Home About us Contact | ||
|
|
||
System Requirements (system + requirement)
Selected AbstractsCPA assessment , the regional assessors' experienceCYTOPATHOLOGY, Issue 2007E. Welsh Many individuals within Laboratory Medicine will be unaware that CPA conducts assessments to two different sets of CPA Standards. There are the Standards for the Medical Laboratory and the Standards for EQA Schemes in Laboratory Medicine. The style and format of both sets of standards is very similar with each being presented in eight sections A , H. The EQA standards are almost identical to the laboratory standards with the exception of the E.F and G standards which are specific to EQA schemes. There are approximately 40 EQA Schemes registered with CPA compared with almost 2 500 laboratories. These EQA schemes vary from very large national/international schemes with numerous analytes to small interpretive schemes run by one individual with a personal interest in that specific subject. The large schemes usually come under the UKNEQAS consortia banner and due to their size and configuration do not present undue problems in the assessment process. Smaller interpretive EQA schemes present a challenge both for the scheme and CPA in gaining accreditation. These schemes are usually within the discipline of Histopathology and are regarded as educational rather than proficiency testing schemes. Very frequently, the scheme is organized by a single individual with a collection of microscope slides, storage facilities for the slides and a computer. This presents the Scheme Organizer with great difficulty in complying with the Quality Management System requirements of the CPA Standards. There are a number of models which can be applied in order to satisfy the requirement of the Quality Management System, but ultimately it must be recognized that in some circumstances it is not possible to accredit these small schemes. The NHSCSP Gynae Cytology EQA Scheme is probably the largest EQA scheme within the UK, in respect of the number of participants and the number of staff supporting the scheme. Scheme Management decided that all nine regions of England would apply for accreditation under one CPA Reference Number. This process meant that the scheme would be assessed as a Managed Pathology Network. This is unique in terms of EQA schemes and presented a number of problems not previously encountered in EQA scheme accreditation. This decision meant that all nine regions must comply with a single Quality Management System and other CPA standards whilst allowing flexibility within the system for each region to facilitate the assessment process specific to their user's requirements. The process worked in a satisfactory manner and the overall outcome was not dissimilar to that of other large EQA schemes. The assessment to the current EQA Standards only commenced in April 2006 whilst the Standards for Medical Laboratories commenced in 2003, and it is perhaps not surprising to find that the principal non-conformities are related to the Quality Management System. This parallels the findings encountered in laboratory accreditation. There is an ongoing educational process for Scheme Management and the Facilitators in each region in how to comply fully with the standards and a commitment to quality improvement which ultimately is beneficial to the participant's of the scheme and to patient safety. [source] The concept of work compatibility: An integrated design criterion for improving workplace human performance in manufacturing systemsHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 4 2004S. Abdallah In this paper, we present the concept of work compatibility as an integrated work design criterion that simultaneously improves human health and safety, productivity, and work quality in manufacturing systems. In this respect, we have modeled work compatibility as a work design parameter that mathematically integrates the energizing (i.e., system resources) and the demand (i.e., system requirements) forces in the work system. A mathematical equation has been derived for the work compatibility matrix. Furthermore, an operating zone has been developed in which there is a region of optimality for the employee to function on practical grounds with a good degree of efficiency and sustainability. An application example is provided to demonstrate the potential of work compatibility to improve productivity and quality along with improvement in worker safety and health. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 379,402, 2004. [source] Reliability factors in business software: volatility, requirements and end-usersINFORMATION SYSTEMS JOURNAL, Issue 3 2002Paul L Bowen Abstract. Many business-oriented software applications are subject to frequent changes in requirements. This paper shows that, ceteris paribus, increases in the volatility of system requirements decrease the reliability of software. Further, systems that exhibit high volatility during the development phase are likely to have lower reliability during their operational phase. In addition to the typically higher volatility of requirements, end-users who specify the requirements of business-oriented systems are usually less technically oriented than people who specify the requirements of compilers, radar tracking systems or medical equipment. Hence, the characteristics of software reliability problems for business-oriented systems are likely to differ significantly from those of more technically oriented systems. [source] Multimedia satellite communications experiments to the international space stationINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 5 2002Carlo Matarasso Abstract In the present concept of the International Space Station ISS, it is planned to provide the communication services between the European Columbus module of the ISS and the ground equipment via the TDRS (tracking and data relay satellite) network provided by the American NASA (National Aeronautics and Space Agency). Especially because of its low uplink data rate, an unacceptable limitation of the communication services with Columbus is to be expected. In order to investigate possible improvements to this situation, the MEDIS proposal studies the feasibility of a 150 Mbps full duplex communication system to the Columbus Module on via two MEO satellites. A mixed topology with optical inter satellite links and Ka-band up/down-links shall be employed. Also possible liaisons with the Artemis mission will be considered. The MEDIS project is a collaboration of Astrium GmbH, which is project manager, Bosch SatCom, GMD-Fokus and the German Aerospace Center (DLR). The preparation phase of the project will investigate the concept of the communications infrastructure and the experiments that could be realized when the MEOs are launched. This stage has been completed in February 2001. An additional study phase followed, which will be completed with a presentation in July 2002. Briefly the following aspects have been studied by DLR in the preparation phase: the overall concept of experimental communication services for Columbus, the system requirements and network topology, the relevant protocol and hardware architectures, useful satellite constellations and link scenarios. Two phases could follow the preparation phase, in phase one the satellite will be launched and the link will be tested. In phase two the satellites will be connected to the ISS. Copyright © 2002 John Wiley & Sons, Ltd. [source] Operational performance metrics for mars exploration roversJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 8-9 2007Edward Tunstel The concept of operational performance metrics and associated measurement issues is explored for deployed robotic systems. The focus is on performance of mobility and robotic arm autonomy exercised on the NASA Mars Exploration Rovers surface mission. This planetary rover mission has been underway for nearly 3 years since January 2004 using two rovers performing separate missions. The autonomy functions of surface navigation, short-distance approach to surface science targets, and robotic placement of armmounted instruments on science targets are considered. Operational metrics that measure performance of these functions relative to system requirements are advocated. Specific metrics are defined and computed using telemetry from the rovers' multiyear operations on Mars and applied to rate performance during their respective missions. An existing methodology is applied to compute metrics with respect to required performance and to aggregate multiple metrics into a composite performance score for each rover. The formulation is augmented to accommodate importance weights that add flexibility in use of the metrics by different potential endusers, e.g., sponsors, program managers, systems engineers, and technologists. A brief example illustrates the application and effect of importance weights on overall rover performance scores. © 2007 Wiley Periodicals, Inc. [source] Improving change tolerance through Capabilities-based design: an empirical analysisJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 2 2008Ramya Ravichandar Abstract We introduce a Capabilities-based approach for constructing large-scale systems such that they are change - tolerant. The inherent complexity of software systems increases their susceptibility to change when subjected to the vagaries of user needs, technology advances, market demands, and other change-inducing factors. Despite the inevitability of change, traditional requirements engineering strives to develop systems based on a fixed solution; a mostly unsuccessful approach as evidenced by the history of system failures. In contrast, we utilize Capabilities,functional abstractions that are neither as amorphous as user needs nor as rigid as system requirements,to architect systems that accommodate change with minimum impact. These entities are designed to exhibit the desirable characteristics of high cohesion, low coupling, and balanced abstraction levels and are generated by a two-phased process called Capabilities Engineering. Phase I mathematically exploits the structural semantics of a function decomposition graph,a representation of user needs,to formulate change-tolerant Capabilities. Phase II optimizes these Capabilities to comply with schedule and technology constraints. In this paper, we present the overall framework of this process and detail the algorithm to identify Capabilities. In addition, we empirically evaluate the change tolerance of Capabilities resulting from Phase I. For this we examine the ripple effect of needs change on a real-world Course Evaluation System based on the original requirements-based design and the corresponding Capabilities-based design. Our experimental results indicate, with statistical significance, that the Capabilities-based design is less impacted by change and thereby improves the change tolerance of the system when subjected to needs volatility. Copyright © 2008 John Wiley & Sons, Ltd. [source] Human-information interaction in time-critical settings: Information needs and use in the emergency roomPROCEEDINGS OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 1 2007Aleksandra Sarcevic Trauma centers are stressful, noisy, and dynamic places, with many people performing complex tasks, and with no technological aids to support their operations. This paper describes research that uses an emergency room as a natural laboratory for investigating information behavior and information sources of trauma team members. Data from interviews, focus groups, and videotaped trauma resuscitations revealed specific information needs in four distinct phases of a trauma event. The most commonly utilized information sources include the patient, vital signs monitor, x-rays images, and other team members. Additionally, data indicated inefficiencies in teamwork and communication. Results from this study can be used to derive system requirements for the design of decision and communication support systems for trauma teams. [source] Estimation of Phosphene Spatial Variability for Visual Prosthesis ApplicationsARTIFICIAL ORGANS, Issue 5 2010Iyad Obeid Abstract Visual prostheses are the focus of intensive research efforts to restore some measure of useful vision to blind or near-blind patients. The development of such technology is being guided to an extent by tools that simulate prosthesis behavior for healthy sighted subjects in order to assess system requirements and configurations. These simulators, however, typically assume purely deterministic phosphene properties and thus do not apply any variability to phosphene size, intensity, or location. We address this issue by presenting data on phosphene variability measured in a blind human subject fitted with an optic nerve prosthesis. In order to correct for normal limitations in human-pointing accuracy, the experimental conditions were repeated with sighted subjects. We conclude that identical optic nerve stimulations can result in phosphenes whose perceived locations vary by up to 5° of deviation angle and 10° of position angle. The consistency of phosphenes presented in the peripheral field of view can vary by an additional 3°. [source] Geospatial identification of optimal straw-to-energy conversion sites in the Pacific Northwest,BIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 4 2010George W. Mueller-Warrant Abstract Previous attempts to develop straw-based bioenergy systems have stumbled at costs of transporting this low-density resource to large-scale, centralized facilities. Success in developing small-scale, distributed technologies (e.g. syngas or pyrolysis bio-oil) that reduce these costs will depend on closely matching system requirements to spatial distribution of available straw. We analyzed straw distribution in the Pacific Northwest to identify optimal sites for facilities ranging from a pilot plant currently under development to larger ones of previous studies. Sites for plants with capacities of 1, 10, or 100 million kg straw y -1 were identified using a ,lowest-hanging-fruit' iterative siting process in which the location of maximum density of straw over an appropriately sized neighborhood was identified, distance from that point necessary to include desired quantity of straw measured, straw assigned to that plant removed from the raster, and the process repeated until all available straw had been assigned. Compared to K-means, our new method sited the first 44% of plants at superior locations in terms of local straw density (i.e. lower transportation costs) and the next 39% at equivalent locations. K-means produced better locations for the final 17% of plants along with superior average results. For the smallest facilities at locations defined by 3-year average available straw density, 1.2 km buffers were adequate to provide straw for the first 10% of plants, with twice that distance sufficient for the first 70%. For the largest plants, 12 km buffers satisfied the first 10% of plants, with 24 km buffers satisfying the first 60%. Buffer distances exceeded 68 km for the final 20% of the largest plants. Siting patterns for the smallest plants were more evenly distributed than larger ones, suggesting that farm-scale technology may be more politically appealing. Smaller plants, however, suffered from higher year-to-year variability in straw supply within pre-defined distances. Published in 2010 by John Wiley & Sons, Ltd. [source] Diagnosing Rejection in Renal Transplants: A Comparison of Molecular- and Histopathology-Based ApproachesAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2009J. Reeve The transcriptome has considerable potential for improving biopsy diagnoses. However, to realize this potential the relationship between the molecular phenotype of disease and histopathology must be established. We assessed 186 consecutive clinically indicated kidney transplant biopsies using microarrays, and built a classifier to distinguish rejection from nonrejection using predictive analysis of microarrays (PAM). Most genes selected by PAM were interferon-,,inducible or cytotoxic T-cell associated, for example, CXCL9, CXCL11, GBP1 and INDO. We then compared the PAM diagnoses to those from histopathology, which are based on the Banff diagnostic criteria. Disagreement occurred in approximately 20% of diagnoses, principally because of idiosyncratic limitations in the histopathology scoring system. The problematic diagnosis of ,borderline rejection' was resolved by PAM into two distinct classes, rejection and nonrejection. The diagnostic discrepancies between Banff and PAM in these cases were largely due to the Banff system's requirement for a tubulitis threshold in defining rejection. By examining the discrepancies between gene expression and histopathology, we provide external validation of the main features of the histopathology diagnostic criteria (the Banff consensus system), recommend improvements and outline a pathway for introducing molecular measurements. [source] | ||||||||||||||||