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Technical Performance (technical + performance)
Selected AbstractsManagement Strategies and Improvement of Performance of Sewer NetworksCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 7 2007Denys Breysse Even when they are conscious about the needs of maintenance to keep the system in a good condition, they lack efficient methods and tools that may help them in taking appropriate decisions. One can say that no really satisfactory and efficient tool exists, enabling the optimization of Inspection, Maintenance, or Rehabilitation (IMR) strategies on such systems. Sewer managers and researchers have been involved for many years in the French National Research Project for Renewal of Non Man Entry Sewer System (RERAU,Réhabilitation des Réseaux d'Assainissement Urbains, in French) to improve their knowledge of these systems and the management policies. During the RERAU project, a specific action has been dedicated to the modeling of asset ageing and maintenance. A special attention has been dedicated to the description of defects and dysfunctions, to the evaluation of performances and its modeling, accounting for its various dimensions (from the point of view of the manager, of the user, of the environment,). After having defined an Index of Technical Performance (ITp), we will introduce the Index of Technical and Economic Performance (ITEp) that is a combined measure of performance (including social costs) and technical costs. This index provides an objective standard tool for managers to compare different alternatives. It is used in the article to compare some simple IMR strategies. It sets the basis of a new method for no-man entry sewer system management, enabling us to analyze the profitableness of investment in terms of both technical and economic performance. [source] Technical Performance of Percutaneous and Laminectomy Leads Analyzed by ModelingNEUROMODULATION, Issue 4 2004Ljubomir Manola Dipl. Abstract The objective of this study was to compare the technical performance of laminectomy and percutaneous spinal cord stimulation leads with similar contact spacing by computer modeling. Monopolar and tripolar (guarded cathode) stimulation with both lead types in a low-thoracic spine model was simulated using UT-SCS software. Dorsal column and dorsal root fiber thresholds were calculated as well as the area of recruited fibers in the dorsal columns, the rostrocaudal span of recruited dorsal root fibers and the energy consumption at discomfort threshold. Tripolar stimulation is superior to monopolar stimulation in the recruitment of the dorsal columns, a percutaneous lead recruits a ,12% larger dorsal column area than a laminectomy lead does. This difference is reduced when the contact spacing of the lead models is the same. A percutaneous lead with significant wire impedance (140 Ohms) consumes ,115,240% more energy, whereas the same lead with negligible wire impedance consumes ,40,85% more energy. A deterioration of all performance parameters is predicted when a percutaneous lead is placed more dorsally in the epidural tissue. When positioned next to the dura mater, a percutaneous lead has a similar performance (fiber recruitment in the dorsal columns and the dorsal roots) as a laminectomy lead with similar contact spacing, but substantially higher energy consumption. The superior clinical performance of the laminectomy lead is most probably due to the difference in volume and insertion technique of the two lead types. [source] Acute toxicity investigations of ester-based lubricants by using biotests with algae and bacteriaENVIRONMENTAL TOXICOLOGY, Issue 4 2004K. Michel Abstract Although ester-based lubricants are ecologically acceptable due to their good biodegradability, there are still some environmental ecotoxicological impacts that have to be considered. Information on the acute ecotoxicological behavior of lubricants is obtained in this work using several single species bioassays. In previous studies it was observed that lubricating fluids containing additives for the enhancement of their technical performance were more problematic than base fluids especially with respect to algae growth inhibition. In order to clarify the influence of additives, the anti-wear additive tri- n -butyl phosphate was tested. It was very toxic to algae though not to bacteria. Additionally, a mixture of this additive with a base fluid is characterized. Despite the high toxicity of the single additive, the water extract of the mixture of tri- n -butyl phosphate with hydraulic base fluid caused almost no toxicity. Therefore, tri- n -butyl phosphate cannot explain the effect observed for the toxicity of water extracts of the commercially available lubricants. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 445,448, 2004. [source] The Relationship between Patients' Perception of Care and Measures of Hospital Quality and SafetyHEALTH SERVICES RESEARCH, Issue 4 2010Thomas Isaac Background. The extent to which patient experiences with hospital care are related to other measures of hospital quality and safety is unknown. Methods. We examined the relationship between Hospital Consumer Assessment of Healthcare Providers and Systems scores and technical measures of quality and safety using service-line specific data in 927 hospitals. We used data from the Hospital Quality Alliance to assess technical performance in medical and surgical processes of care and calculated Patient Safety Indicators to measure medical and surgical complication rates. Results. The overall rating of the hospital and willingness to recommend the hospital had strong relationships with technical performance in all medical conditions and surgical care (correlation coefficients ranging from 0.15 to 0.63; p<.05 for all). Better patient experiences for each measure domain were associated with lower decubitus ulcer rates (correlations ,0.17 to ,0.35; p<.05 for all), and for at least some domains with each of the other assessed complications, such as infections due to medical care. Conclusions. Patient experiences of care were related to measures of technical quality of care, supporting their validity as summary measures of hospital quality. Further study may elucidate implications of these relationships for improving hospital care. [source] Using discrete event simulation to model excavator operator performanceHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 5 2010Khaliah Hughes Abstract The traditional design process of fluid power systems such as hydraulic excavators has placed much emphasis on technical performance rather than human components. This research aims to develop human-performance models to assess operator performance and human interaction during excavation processes. Task analysis, time studies, and statistical distributions were developed into task-network models and imbedded into four Micro Saint simulation models with regard to various expertise and control types. An empirical study was conducted using the simulation models. Results indicated that both expertise and control type had a significant impact on operator performance, resulting in both time and consistency differences at various points during excavation processes. Models also revealed implications of operator fatigue leading to stress for the operator. Recommendations suggest that designers consider the placement of controls and measures to reduce operator workload for better performance in future systems. © 2010 Wiley Periodicals, Inc. [source] Multiple displacement amplification to create a long-lasting source of DNA for genetic studies,HUMAN MUTATION, Issue 7 2006Lovisa Lovmar Abstract In many situations there may not be sufficient DNA collected from patient or population cohorts to meet the requirements of genome-wide analysis of SNPs, genomic copy number polymorphisms, or acquired copy number alternations. When the amount of available DNA for genotype analysis is limited, high performance whole-genome amplification (WGA) represents a new development in genetic analysis. It is especially useful for analysis of DNA extracted from stored histology slides, tissue samples, buccal swabs, or blood stains collected on filter paper. The multiple displacement amplification (MDA) method, which relies on isothermal amplification using the DNA polymerase of the bacteriophage ,29, is a recently developed technique for high performance WGA. This review addresses new trends in the technical performance of MDA and its applications to genetic analyses. The main challenge of WGA methods is to obtain balanced and faithful replication of all chromosomal regions without the loss of or preferential amplification of any genomic loci or allele. In multiple comparisons to other WGA methods, MDA appears to be most reliable for genotyping, with the most favorable call rates, best genomic coverage, and lowest amplification bias. Hum Mutat 27(7), 603,614, 2006. © 2006 Wiley-Liss, Inc. [source] A comprehensive techno-economic analysis method for power generation systems with CO2 captureINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 4 2010Gang Xu Abstract A new comprehensive techno-economic analysis method for power generation systems with CO2 capture is proposed in this paper. The correlative relationship between the efficiency penalty, investment increment, and CO2 avoidance cost is established. Through theoretical derivation, typical system analysis, and variation trends investigation, the mutual influence between technical and economic factors and their impacts on the CO2 avoidance cost are studied. At the same time, the important role that system integration plays in CO2 avoidance is investigated based on the analysis of a novel partial gasification CO2 recovery system. The results reveal that for the power generation systems with CO2 capture, the efficiency penalty not only affects the costs on fuel, but the incremental investment cost for CO2 capture (U.S.$,kW,1) as well. Consequently, it will have a decisive impact on the CO2 avoidance cost. Therefore, the added attention should be paid to improve the technical performance in order to reduce the efficiency penalty in energy system with CO2 capture and storage. Additionally, the system integration may not only decrease the efficiency penalty, but also simplify the system structure and keep the investment increment at a low level, and thereby it reduces the CO2 avoidance cost significantly. For example, for the novel partial gasification CO2 recovery system, owing to system integration, its efficiency can reach 42.2%, with 70% of CO2 capture, and its investment cost is only 87$,kW,1 higher than that of the reference IGCC system, thereby the CO2 avoidance cost is only 6.23$,t,1 CO2. The obtained results provide a comprehensive technical,economical analysis method for energy systems with CO2 capture useful for reducing the avoidance costs. Copyright © 2009 John Wiley & Sons, Ltd. [source] The role of policy instruments for promoting combined heat and power production with low CO2 emissions in district heating systemsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 6 2005Å. Marbe Abstract Policy instruments clearly influence the choice of production technologies and fuels in large energy systems, including district heating networks. Current Swedish policy instruments aim at promoting the use of biofuel in district heating systems, and at promoting electric power generation from renewable energy sources. However, there is increasing pressure to harmonize energy policy instruments within the EU. In addition, natural gas based combined cycle technology has emerged as the technology of choice in the power generation sector in the EU. This study aims at exploring the role of policy instruments for promoting the use of low CO2 emissions fuels in high performance combined heat and power systems in the district heating sector. The paper presents the results of a case study for a Swedish district heating network where new large size natural gas combined cycle (NGCC) combined heat and power (CHP) is being built. Given the aim of current Swedish energy policy, it is assumed that it could be of interest in the future to integrate a biofuel gasifier to the CHP plant and co-fire the gasified biofuel in the gas turbine unit, thereby reducing usage of fossil fuel. The goals of the study are to evaluate which policy instruments promote construction of the planned NGCC CHP unit, the technical performance of an integrated biofuelled pressurized gasifier with or without dryer on plant site, and which combination of policy instruments promote integration of a biofuel gasifier to the planned CHP unit. The power plant simulation program GateCycle was used for plant performance evaluation. The results show that current Swedish energy policy instruments favour investing in the NGCC CHP unit. The corresponding cost of electricity (COE) from the NGCC CHP unit is estimated at 253 SEK MWh,1, which is lower than the reference power price of 284 SEK MWh,1. Investing in the NGCC CHP unit is also shown to be attractive if a CO2 trading system is implemented. If the value of tradable emission permits (TEP) in such as system is 250 SEK tonne,1, COE is 353 SEK MWh,1 compared to the reference power price of 384 SEK MWh,1. It is possible to integrate a pressurized biofuel gasifier to the NGCC CHP plant without any major re-design of the combined cycle provided that the maximum degree of co-firing is limited to 27,38% (energy basis) product gas, depending on the design of the gasifier system. There are many parameters that affect the economic performance of an integrated biofuel gasifier for product gas co-firing of a NGCC CHP plant. The premium value of the co-generated renewable electricity and the value of TEPs are very important parameters. Assuming a future CO2 trading system with a TEP value of 250 SEK tonne,1 and a premium value of renewable electricity of 200 SEK MWh,1 COE from a CHP plant with an integrated biofuelled gasifier could be 336 SEK MWh,1, which is lower than both the reference market electric power price and COE for the plant operating on natural gas alone. Copyright © 2005 John Wiley & Sons, Ltd. [source] Comparison of the technical and clinical performance of the Elecsys® HBsAg II assay with the Architect®, AxSym®, and Advia® Centaur HBsAg screening assaysJOURNAL OF MEDICAL VIROLOGY, Issue 5 2010S. Louisirirotchanakul Abstract South East Asia has some of the highest prevalence rates of hepatitis B virus (HBV) infection (,8%) in the world, and the emergence of hepatitis B surface antigen (HBsAg) mutant strains is a growing problem. Assays with the highest levels of sensitivity, including mutant detection, should be used for routine HBsAg screening. In this large multicenter study, the clinical and technical performance of the fully automated Elecsys HBsAg II assay was compared with the Architect, AxSYM, and Advia Centaur HBsAg assays for HBsAg screening. Nine laboratories (three each from Thailand, Korea, and Singapore) compared the Elecsys HBsAg II assay with their routine HBsAg screening assay against a range of stored and routine clinical samples, including recombinant mutants. The Elecsys HBsAg II assay demonstrated equivalent sensitivity and specificity to the Architect HBsAg assay. However, the Elecsys HBsAg II assay recognized a native mutant sample (L94S, L97V, L98V, T123A) that the Architect HBsAg assay failed to detect. The AxSYM and Advia Centaur HBsAg assays appeared less sensitive for the detection of early HBV infection and also failed to detect some of the recombinant mutant strains. There was almost complete agreement between the Elecsys HBsAg II assay and comparator assays with respect to routine serum samples. The results of this study demonstrate that the Elecsys HBsAg II assay is a highly sensitive and specific screening assay for HBsAg and detects reliably the most important and clinically relevant HBV mutants and genotypes. It is suitable for routine HBsAg screening in Asia. J. Med. Virol. 82: 755,762, 2010. © 2010 Wiley-Liss, Inc. [source] Technical Performance of Percutaneous and Laminectomy Leads Analyzed by ModelingNEUROMODULATION, Issue 4 2004Ljubomir Manola Dipl. Abstract The objective of this study was to compare the technical performance of laminectomy and percutaneous spinal cord stimulation leads with similar contact spacing by computer modeling. Monopolar and tripolar (guarded cathode) stimulation with both lead types in a low-thoracic spine model was simulated using UT-SCS software. Dorsal column and dorsal root fiber thresholds were calculated as well as the area of recruited fibers in the dorsal columns, the rostrocaudal span of recruited dorsal root fibers and the energy consumption at discomfort threshold. Tripolar stimulation is superior to monopolar stimulation in the recruitment of the dorsal columns, a percutaneous lead recruits a ,12% larger dorsal column area than a laminectomy lead does. This difference is reduced when the contact spacing of the lead models is the same. A percutaneous lead with significant wire impedance (140 Ohms) consumes ,115,240% more energy, whereas the same lead with negligible wire impedance consumes ,40,85% more energy. A deterioration of all performance parameters is predicted when a percutaneous lead is placed more dorsally in the epidural tissue. When positioned next to the dura mater, a percutaneous lead has a similar performance (fiber recruitment in the dorsal columns and the dorsal roots) as a laminectomy lead with similar contact spacing, but substantially higher energy consumption. The superior clinical performance of the laminectomy lead is most probably due to the difference in volume and insertion technique of the two lead types. [source] An Integrated Framework for Measuring Product Development Performance in High Technology IndustriesPRODUCTION AND OPERATIONS MANAGEMENT, Issue 2 2005Debasish N. Mallick We present an integrated framework for measuring product development performance. The framework consists of a three stage model for exploring the relationships between metrics used by design, manufacturing, marketing functions, and overall commercial success. Using a cross-sectional survey of 383 product development professionals working on 38 product development projects in the high-tech electronic assembled goods manufacturing sector, we provide empirical evidence of the proposed framework. The findings indicate that in the high-tech manufacturing sector (1) commercial success of new product development projects is primarily determined by market share, (2) gain in market share is primarily driven by lower unit cost and not by technical performance, and (3) reduction in unit cost is primarily driven by the increased speed of new product development and not by the R&D budget. The study failed to identify any significant association between R&D budget and technical performance, and development speed and technical performance. [source] Grid-connected photovoltaic systems: the Brazilian experience and the performance of an installationPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 5 2001Sérgio Henrique Ferreira de Oliveira Just as in several other countries, the Brazilian experience of installing in place solar photovoltaic technology was first aimed at meeting the needs of rural areas. More recently, the effects of the international trend towards grid-connected photovoltaic systems are beginning to be felt in Brazil. In less than five years, the first four grid-connected photovoltaic systems have been installed, and other projects are in progress. This work presents the overall characteristics of the first four systems and the technical performance achieved by one of them, with an annual production in the range of 1500,kW,h/kWp. Copyright © 2001 John Wiley & Sons, Ltd. [source] Improving glandular coverage during prostate biopsy using a long-core needle: technical performance of an end-cutting needleBJU INTERNATIONAL, Issue 1 2002G.N. Ubhayakar Objective To compare the technical performance of a 33-mm core-length biopsy needle with that of the standard 18 mm needle, as many prostate cancers are isoechoic and in large prostates the tissue coverage with the 18 mm needle is inadequate. Patients and methods A 33-mm core length BioPinceÔ VSL disposable needle (Amedic, Sweden) and a standard TruCut 18 mm needle (Medical Device Technology Inc., FL, USA) were used to take prostatic biopsies in two groups of 15 patients. The following variables were assessed for each group: mean core length, core quality, capsular coverage (one or both capsules within the specimen), and side-effects in the first week after biopsy (for the BioPince group, surveyed using a self-completed questionnaire). The results were compared with historical data from a group of 30 patients biopsied using the standard needle. Results For the BioPince and standard groups the mean (sd) core length was 19.4 (8.9) and 14.9 (5.1) mm, respectively. Four needles in the BioPince group failed to capture a sample, requiring needle replacement. The samples were fragmented in 15 of 90 (17%) and 41 of 90 (46%) biopsies in the BioPince and standard groups, respectively (P < 0.05). Specimens had both capsules present in five of 90 (6%) and four of 90 (4%), respectively. Within 7 days minor bleeding was the most common side-effect. Pain after biopsy was the only symptom showing a significant difference between the groups, at six of 15 and none (P = 0.001), respectively. The incidence of haematuria, haematospermia and rectal bleeding was similar in the two groups (P > 0.05), but fever more common (three vs none) in the BioPince group (P = 0.06). Conclusion When set at a 33-mm stroke length, the BioPince needle increases the mean core length by 30%, with less fragmentation than a standard 18 mm needle. However, it has a significant failure rate for capture (27% needle replacement rate), slightly greater morbidity (pain and possibly fever) and shows no advantage in capsular coverage. Therefore, there are shortcomings with this end-cutting needle when used at 33 mm core length. [source] Percutaneous intervention for unprotected left main disease prior to explantation of a left ventricular assist deviceCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2003Samuel M. Butman MD Abstract Percutaneous coronary intervention of unprotected left main coronary arterial disease is an alternative to surgical revascularization in selected patients. In this report, a patient with an implanted left ventricular assist device (LVAD) underwent successful coronary intervention prior to its planned removal. The implanted LVAD clearly assisted the technical performance of the intervention. Cathet Cardiovasc Intervent 2003;59:471,474. © 2003 Wiley-Liss, Inc. [source] | ||||||||||||||||