37 research outputs found
Effects of ATF cladding properties on PWR responses to an SBO accident: A sensitivity analysis
No full textTo investigate the effects of ATF cladding properties on the plant responses to severe accidents, shortterm station blackout simulations and sensitivity analyses on hypothetical cladding materials were performed using MAAP code. For sensitivity analyses, 7 hypothetical cladding materials were used. Hypo-0 was the reference cladding whose properties are anticipated to show the poorest fuel performance during an STSBO. The input property values for Hypo-1 through Hypo-6 were selected by changing each variable independently while keeping the others at their reference values. The onset times for core uncovery and cladding oxidation were similar for all the simulation cases, implying that single property cannot affect the event times. A main conclusion is that a large enthalpy of cladding can delay the increase in temperatures of fuel and cladding by playing a role as a heat sink after the core uncovery occurs, resulting in the delayed hot leg rupture. (c) 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Correction: Alrwashdeh, M.; Alameri, S.A. Chromium-Coated Zirconium Cladding Neutronics Impact for APR-1400 Reactor Core. <i>Energies</i> 2022, <i>15</i>, 8008
No full textIn the original publication [...
Dental Technology Services and Industry Trends in New Zealand
Get PDFObjective: This cross-sectional survey provides a snapshot of the New Zealand dental technology industry and identifies the range and cost of dental laboratory services.
Background: Developing an understanding on the commercial dental laboratories environment can provide insight into the entire dental industry and help identify factors that influence the industry.
Method: Two main questionnaires were used targeting dental laboratory owners and dental technician employees. The dental laboratory owners’ questionnaire had six sections (demographics, workforce information, services provided, revenue, and personal opinion). The dental technician employees’ survey consisted of three sections covering: demographics, workforce information and personal opinion. A web-based survey was the primary method for data collection. Categorical variables were tested for significance using SPSS statistical software (Version 19.0; SPSS Inc., Chicago, USA) with an alpha level of 0.05.
Results: Twenty six (41.3%) of responding dental laboratories use services from other New Zealand dental laboratories, 14 (22.2%) were using offshore laboratories. In 2010, over half of responding dental laboratories (19; 55.9%) made more than $250,000 annually. Clinical dental technicians are earning the highest hourly rate and removable prostheses were the most common dental laboratory services in New Zealand. The main reason provided for attrition of dental clients was due to them leaving the country, retirement or death.
Conclusion: There are multiple factors influencing the dental technology industry. Clinical dental technology appears to be prospering and while facing difficulties, the dental technology industry is adapting and still viable
Dental Technology Services and Industry Trends in New Zealand
No full textObjective: This cross-sectional survey provides a snapshot of the New Zealand dental technology industry and identifies the range and cost of dental laboratory services.
Background: Developing an understanding on the commercial dental laboratories environment can provide insight into the entire dental industry and help identify factors that influence the industry.
Method: Two main questionnaires were used targeting dental laboratory owners and dental technician employees. The dental laboratory owners’ questionnaire had six sections (demographics, workforce information, services provided, revenue, and personal opinion). The dental technician employees’ survey consisted of three sections covering: demographics, workforce information and personal opinion. A web-based survey was the primary method for data collection. Categorical variables were tested for significance using SPSS statistical software (Version 19.0; SPSS Inc., Chicago, USA) with an alpha level of 0.05.
Results: Twenty six (41.3%) of responding dental laboratories use services from other New Zealand dental laboratories, 14 (22.2%) were using offshore laboratories. In 2010, over half of responding dental laboratories (19; 55.9%) made more than $250,000 annually. Clinical dental technicians are earning the highest hourly rate and removable prostheses were the most common dental laboratory services in New Zealand. The main reason provided for attrition of dental clients was due to them leaving the country, retirement or death.
Conclusion: There are multiple factors influencing the dental technology industry. Clinical dental technology appears to be prospering and while facing difficulties, the dental technology industry is adapting and still viable
Chromium-Coated Zirconium Cladding Neutronics Impact for APR-1400 Reactor Core
No full textThe accident-tolerant fuel concept involves replacing the conventional cladding system (zirconium) with a new material or coating that has specific thermomechanical properties. The aim of this study is to evaluate the neutronics performance of a chromium coating concept and design solutions. A Zircaloy–uranium fuel system (Zr–U) is currently used as a standard fuel system in pressurized water reactors around the world. This investigation presents the benefits of utilizing an alternative cladding material such as chromium coating and the effects on the thermal neutron parameters of the way in which the chromium coating is introduced in the reactor fuel. Among these significant benefits is an increase in the reactor fuel’s thermal conductivity, which improves reactor safety. Two types of fuel-cladding systems were investigated: Zircaloy–uranium (Zr–U) and Zircaloy–chromium (Zr–Cr–U) coating fuel systems. Neutronics analysis evaluations were performed for the selected fuel assemblies and a two-dimensional full core based on an APR-1400 reactor design. Neutronics analyses were performed for the application of the new fuel-cladding material systems using the reactor-physics Monte Carlo code Serpent 2.31
SiC and FeCrAl as Potential Cladding Materials for APR-1400 Neutronic Analysis
No full textThe aim of this study is to investigate the potential improvement of accident-tolerant fuels in pressurized water reactors for replacing existing reference zircaloy (Zr) fuel-cladding systems. Three main strategies for improving accident-tolerant fuels are investigated: enhancement of the present state-of-the-art zirconium fuel-cladding system to improve oxidation resistance, replacement of the current referenced fuel-cladding system material with an alternative high-performance oxidation-resistant cladding, and replacement of the current fuel with alternative fuel forms. This study focuses on a preliminary analysis of the neutronic behavior and properties of silicon carbide (SiC)-fuel and FeCrAl cladding systems, which provide a better safety margin as accident-tolerant fuel systems for pressurized water reactors. The typical physical behavior of both cladding systems is investigated to determine their general neutronic performance. The multiplication factor, thermal neutron flux spectrum, 239Pu inventory, pin power distribution, and radial power are analyzed and compared with those of a reference Zr fuel-cladding system. Furthermore, the effects of a burnable poison rod (Gd2O3) in different fuel assemblies are investigated. SiC cladding assemblies present a softer neutron spectrum and a lower linear power distribution compared with the conventional Zr-fuel-cladding system. Additionally, the SiC fuel-cladding system exhibits behaviors that are consistent with the neutronic behavior of conventional Zr fuel-cladding systems, thereby affording greater economic and safety improvements
Two-Dimensional Full Core Analysis of IFBA-Coated TRISO Fuel Particles in Very High Temperature Reactors
No full textReactor Monte Carlo (RMC) model validation and verification in compare with MCNP for plate-type reactor
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A survey of mobile ad-hoc networks based on fuzzy logic
No full textWirelessly connected mobile devices with self-configuration need to have reliable communication. The deployment of routing techniques in dynamic Ad-Hoc networks has enhanced traffic management. In mobile Ad-Hoc networks (MANETs), each node freely moves from one place to another and acts as a router. However, mobile networks are also considered Ad-Hoc wireless networks. Wireless technologies are merged in MANETs to improve communication among the nodes. MANETs can be easily installed in civil and military applications. This paper presents a survey study on MANETs using fuzzy logic-based techniques based on reviewed literature. Also, some applications are discussed, which include forestry, search and rescue operations, and digital libraries. In addition, different types of routing protocols are incorporated, like proactive, reactive, hybrid, swarm intelligence, and fuzzy logic-based routing. However, a brief overview of fuzzy systems and different real-time applications that use fuzzy technology as a controller are given preference. Besides, investigating fuzzy logic in MANETs, especially in routing protocols, has attracted researchers to this field of study.Bezdrátově připojená mobilní zařízení s vlastní konfigurací musí mít spolehlivou komunikaci. Nasazení směrovacích technik v dynamických sítích Ad-Hoc zlepšilo řízení provozu. V mobilních sítích Ad-Hoc (MANET) se každý uzel volně pohybuje z jednoho místa na druhé a funguje jako router. Mobilní sítě jsou však také považovány za bezdrátové sítě Ad-Hoc. Bezdrátové technologie jsou sloučeny v MANETech, aby se zlepšila komunikace mezi uzly. MANETy lze snadno nainstalovat v civilních a vojenských aplikacích. Tento článek představuje přehledovou studii o MANETech s využitím technik založených na fuzzy logice na základě recenzované literatury. Diskutovány jsou také některé aplikace, které zahrnují lesnictví, pátrací a záchranné operace a digitální knihovny. Kromě toho jsou začleněny různé typy směrovacích protokolů, jako je proaktivní, reaktivní, hybridní, swarm intelligence a směrování založené na fuzzy logice. Upřednostňuje se však stručný přehled fuzzy systémů a různých aplikací v reálném čase, které používají fuzzy technologii jako regulátor. Kromě toho zkoumání fuzzy logiky v MANETech, zejména ve směrovacích protokolech, přilákalo výzkumníky do této oblasti studia
Association of ANA seropositivity with RF, CRP, Brucellosis test in patients with SLE, a compression between immunofluorescence technique and latex agglutination
Get PDFObjectives The present study aims to inspect the connection between patients with SLE and RF, CRP, Brucellosis and compression between immunofluorescence technique and latex agglutination method to detect ANA.
Methods A total of 90 serum sample collected from patients with symptoms and signs of SLE those send to the immunity lab in Al-Hussein hospital. The immunofloriscent ANA test, SLE latex agglutination test, RF, CRP and Rose Bengal tests were done to all these samples.
Results The results show that there was significant difference between males (16%) and females (84%) patients with sign and symptom of SLE, while there was no significant difference in CRP, RF, in patients with SLE positive (50%,17%) and SLE negative patients (48.5%,17%), continuously Rose Bengal test is higher in SLE negative patients than in SLE positive patients (15.2%, 8.3%). Finally, there is significant difference in diagnosis of SLE disease between IF technique and latex agglutination test (41.6%, 100%).
Conclusions Latex agglutination test for ANA detection is reliable, specific but less sensitive test when compared to SLE IF test. There are significance differences in Rose Bengal test in SLE negative and in SLE positive patient’s, while there are non-significance difference in CRP, RF in SLE positive samples and in SLE negative samples
