45,010 research outputs found
Coupled thermodynamic and biologic modelling of Legionella pneumophila proliferation in domestic hot water systems
The production of Domestic Hot Water (DHW) dominates the total energy demand. One of the main reasons for the high energy demand is that DHW is stored and distributed at temperatures above 55°C to mitigate the risk of infecting the DHW system with Legionella Pneumophila. At these temperatures, Legionella bacteria are effectively killed. For most of the applications of DHW, temperatures of only 30-40°C are required. This disparity (between 55 and 30-40°C) doubles the temperature difference between the DHW system and the environment and has a detrimental effect on the efficiency of DHW production units.
A simulation model will be developed that allows to investigate the infection risk for Legionella in the design phase of a DHW system and to test the effectiveness of disinfection techniques on an infected system. In addition to the modeling work, a test rig will be built and the relevant temperature and use profiles will be measured in DHW systems of several buildings. With the thermodynamically validated model, the Legionella infection risk of 5 to 10 DHW system configurations will be assessed and new design guidelines will be proposed based on an optimization study that looks for the trade-off between infection risk and energy efficiency
Supersymmetric particle mass measurement with the boost-corrected contransverse mass
A modification to the contransverse mass (MCT) technique for measuring the
masses of pair-produced semi-invisibly decaying heavy particles is proposed in
which MCT is corrected for non-zero boosts of the centre-of-momentum (CoM)
frame of the heavy states in the laboratory transverse plane. Lack of knowledge
of the mass of the CoM frame prevents exact correction for this boost, however
it is shown that a conservative correction can nevertheless be derived which
always generates an MCT value which is less than or equal to the true value of
MCT in the CoM frame. The new technique is demonstrated with case studies of
mass measurement with fully leptonic ttbar events and with SUSY events
possessing a similar final state.Comment: 33 pages, 33 .eps figures, JHEP3 styl
On Machine Capacitance Dimensional and Surface Profile Measurement System
A program was awarded under the Air Force Machine Tool Sensor Improvements Program Research and Development Announcement to develop and demonstrate the use of a Capacitance Sensor System including Capacitive Non-Contact Analog Probe and a Capacitive Array Dimensional Measurement System to check the dimensions of complex shapes and contours on a machine tool or in an automated inspection cell. The manufacturing of complex shapes and contours and the subsequent verification of those manufactured shapes is fundamental and widespread throughout industry. The critical profile of a gear tooth; the overall shape of a graphite EDM electrode; the contour of a turbine blade in a jet engine; and countless other components in varied applications possess complex shapes that require detailed and complex inspection procedures. Current inspection methods for complex shapes and contours are expensive, time-consuming, and labor intensive
Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 314)
This bibliography lists 139 reports, articles, and other documents introduced into the NASA scientific and technical information system in August, 1988
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Simple network management protocol co- existence with hydrocarbon process automation communication real-time network
Hydrocarbon Process Automation Applications (HPAA) utilizes Real-time network connecting process instrumentations, controllers, and real-time logic control applications. Conventional practice is to dedicate a real-time network for process automation applications and prevent other applications from utilizing the same infrastructure. An important application that can help optimize, improve network performance, and provide rapid response time in network diagnostics and mitigation is Simple Network Management Protocol (SNMP). This paper addresses the co-existence of SNMP traffic with real-time applications. The impacts of activating this protocol with the real-time HPAA utilizing high speed Ethernet network design will be examined. Empirical data for an implemented Hydrocarbon process automation system will be used to illustrate the interdependency of application performance, traffic mix, and potential areas of improvements. The outcomes of this effort demonstrate the co-existence of SNMP with HPPA, given special considerations (i.e., bandwidth, number of applications, etc.)
Aerospace Medicine and Biology. A continuing bibliography with indexes
This bibliography lists 244 reports, articles, and other documents introduced into the NASA scientific and technical information system in February 1981. Aerospace medicine and aerobiology topics are included. Listings for physiological factors, astronaut performance, control theory, artificial intelligence, and cybernetics are included
Validating Pharma Machinery: A Journey To Find a Line Somewhere Above Baseline with Science and Risk Consideration for Cost Efficient Facility Requirement
Every industries should be aware about how their product quality are build. It began with the end in mind about a detail specification of the product, a quality atribut designed to the product profile, process and technology choice. Then it will initiate a requirement of the facility for those need. Pharmaceutical product is one in many manufacturing industries that need to be carefully manage in term of product quality and the consideration that it can be harm to the consumer. The impact can also come from a requirement specification of its facility1. To protect the drugs consumer, we can use the term 'patient safety' then, authority made a regulation that became a coridor to lead the industry on how the good manufacturing pratices should be conducted. Regulator put it in the terminology: GMP (Good Manufacturing Practices). But they give only general statement about what a 'good manufacturing' is. Most of the time it needs detail technical explanation. Especially for the engineers perspective. Some pharmaceutical engineering professional organization try to describe the minimum requirement should be designed for pharmaceutical facility purpose. A Baseline. But the baseline sometimes is not a clear bold line, Most of the time, in very detail technical decision, it can be a wide grey area. How high we put our requirement level above baseline corelate with how expensive the cost will be
Technical Efficiency of Nigerian Insurance Companies
This paper uses data envelopment analysis (DEA) to evaluate the performance of Nigerian insurance companies, from 2001 to 2005, combining operational and financial variables. The paper also analyses the situations of these companies in relation to the frontier of best practices. In addition, it tests for the roles played by dimension, bank network and market share in the efficiency of the Nigerian insurance companies. The implications of this research for managerial purposes are then drawn.Nigerian insurance companies; Data Envelopment Analysis; Efficiency.
Methodological considerations in the analysis of fecal glucocorticoid metabolites in tufted capuchins (Cebus apella)
Analysis of fecal glucocorticoid (GC) metabolites has recently become the standard method to monitor adrenocortical activity in primates noninvasively. However, given variation in the production, metabolism, and excretion of GCs across species and even between sexes, there are no standard methods that are universally applicable. In particular, it is important to validate assays intended to measure GC production, test extraction and storage procedures, and consider the time course of GC metabolite excretion relative to the production and circulation of the native hormones. This study examines these four methodological aspects of fecal GC metabolite analysis in tufted capuchins (Cebus apella). Specifically, we conducted an adrenocorticotrophic hormone (ACTH) challenge on one male and one female capuchin to test the validity of four GC enzyme immunoassays (EIAs) and document the time course characterizing GC me- tabolite excretion in this species. In addition, we compare a common field-friendly technique for extracting fecal GC metabolites to an established laboratory extraction methodology and test for effects of storing “field extracts” for up to 1 yr. Results suggest that a corticosterone EIA is most sensitive to changes in GC production, provides reliable measures when extracted according to the field method, and measures GC metabolites which remain highly stable after even 12 mo of storage. Further, the time course of GC metabolite excretion is shorter than that described yet for any primate taxa. These results provide guidelines for studies of GCs in tufted capuchins, and underscore the importance of validating methods for fecal hormone analysis for each species of interest
Biofunctionalized all-polymer photonic lab on a chip with integrated solid-state light emitter
A photonic lab on a chip (PhLOC), comprising a solid-state light emitter (SSLE) aligned with a biofunctionalized optofluidic multiple internal reflection (MIR) system, is presented. The SSLE is obtained by filling a microfluidic structure with a phenyltrimethoxysilane (PhTMOS) aqueous sol solution containing a fluorophore organic dye. After curing, the resulting xerogel solid structure retains the emitting properties of the fluorophore, which is evenly distributed in the xerogel matrix. Photostability studies demonstrate that after a total dose (at l = 365 nm) greater than 24 J/cm2, the xerogel emission decay is only 4.1%. To re-direct the emitted light, the SSLE includes two sets of air mirrors that surround the xerogel. Emission mapping of the SSLE demonstrates that alignment variations of 150 mm (between the SSLE and the external pumping light source) provide fluctuations in emitted light smaller than 5%. After this verification, the SSLE is monolithically implemented with a MIR, forming the PhLOC. Its performance is assessed by measuring quinolone yellow, obtaining a limit of detection (LOD) of (0.60 +/- 0.01) mM. Finally, the MIR is selectively biofunctionalized with horseradish peroxidase (HRP) for the detection of hydrogen peroxide (H2O2) target analyte, obtaining a LOD of (0.7 +/- 0.1) mM for H2O2, confirming, for the first time, that solid-state xerogel-based emitters can be massively implemented in biofunctionalized PhLOCs
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