bluuebunny/crossref_metadata_2025 huggingface dataset:
The Design of Area Radiation Monitoring System for the Nuclear Accident at Sea
Authors: Gao Feng , Zhang Jianguo , Yang Yifang , Wang Zhentao , Wang Haijun
Published: February 2014

It was well known that the radiation monitoring is an essential part of dealing with a nuclear accident safely. When a Nuclear-powered Vessel (NPV) was in the event of a nuclear accident at sea, the rescue vessels with different functions would rush to the scene of the accident to implement a rescue. In order to ensure the radiation safety of the emergency personnel aboard the rescue vessels, some kinds of radiation measuring devices should be installed and the ambient radiation levels should be measured. However, the occurrence of the nuclear accident at sea is few and unforeseeable, so the rescue vessels usually perform other ordinary works and are dispersed in different departments. Since that, the service efficiency of the fixed radiation measuring devices installed in the rescue vessels is low. What’s more, it is difficult keep all of them at a good condition. In order to resolve these contradictions, a new type of radiation monitoring system, which has been called as Area Radiation Monitoring System for the Nuclear Accident at Sea (ARMS), is proposed in this paper. With the application of Building Block Design, the ARMS becomes easy to be assembled and disassembled, so the centralized maintenance comes true. The ARMS has a more wide range of uses, not only for the nuclear accident emergency radiation monitoring at sea, but also for ordinary or emergency radiation monitoring for monitoring nuclear power plant and the Nuclear-powered Vessel harbor. The component and function of the monitoring system as well as its Data Transmission Networks are introduced in this paper.
Preliminary Investigation of Heat-Transfer Correlation for Upward Flow of CO2 at Supercritical Pressure
Authors: Saltanov Eugene , Pioro Igor , Harvel Glenn
Published: February 2014

The development of Generation IV nuclear reactors is an ongoing worldwide interdisciplinary effort. Canada is involved with the development of the SuperCritical Water-cooled Reactor (SCWR). One of the numerous engineering challenges associated with this development is to ensure intensive and stable heat transfer to SuperCritical Water (SCW) in a core.

It is very important to develop sophisticated theoretical models to improving understanding of physical processes behind forced-convective heat transfer and its deterioration in near-critical region. However, not all turbulent models implemented in Computational Fluid Dynamics (CFD) codes are applicable to heat transfer at supercritical pressures. Additionally these codes should be first tuned on the basis of experimental data and, after that, used in similar calculations. Therefore, there is still a great reliance on 1D heat-transfer correlations for preliminary calculations.

Performing experiments in SCW is extremely expensive due to the high temperatures and pressures involved. Therefore, it is reasonable to study the general properties of SuperCritical Fluids (SCF) by running experiments with modelling fluids; for example, carbon dioxide, which is widely used as a modeling fluid. In view of this, there is a need to compile a large database that will include experimental data on forced-convection heat-transfer to SuperCritical (SC) CO2 within a wide range of operational parameters. To date, a part of this database has been produced. It contains the bulk-fluid and wall temperatures of CO2 flowing upward in a vertical bare tube. CO2 is at supercritical pressure and the bulk-fluid and wall temperatures are below or above the pseudocritical temperature at the inlet of the test-section.

Therefore, the objectives of this paper are:

1) to propose a correlation in a standard non-dimensional form, which will generalize data within ±25%;

2) to compare this correlation with the most recent, as well as previous 1D correlations for SC CO2 and SCW (appropriate scaling is performed).
On Operational and Start-Up Transients in an Accelerator Driven Systems
Authors: dos Santos Rubens Souza
Published: February 2014

Accelerator Driven Systems (ADS) are subcritical nuclear reactor cores driven by external spallation neutron source. These systems are currently under investigation to be used as minor actinide burners and also as transmuters of long lived fission products. The subcriticality level plays an important rule in the control of the system. Low subcriticality level more source dominant is the system. In this paper one analyzes two transients to analyze the feedback effect on power of the Accelerator Driven Systems, since they cover a wide range of temperature variations. These operational transients are a beam interruption in power and a startup one, when the ADS are powered up from zero power to power operation. Numerical results shown that ADS can not reach the nominal operation temperatures if the systems operate next to critical ones. In a beam interruption transient systems are not affected if operated as critical ones.
The Optimization Design of Lower Plenum and Distribution Plates in MSR
Authors: Zhou Jianjun , Qiu Suizheng , Guo Zhangpeng , Su Guanghui
Published: February 2014

Molten salt reactor was one of six Generation IV reactor types, which uses the liquid molten salt as the coolant and fuel solvent. In transmutation of actinides and long-lived fission products have marked advantages. As a liquid reactor the physical property and thermo-characteristic is different to solid fuel and water coolant reactors, which was influenced by many factors. MOSART was one of the advanced molten salt reactors concept design, which can burners TRU from LWR spent fuel. The reactor core does not contain graphite structure elements, so the flow pattern was potentially complex and may significantly affect the fuel temperature distributions. The optimizations of the salt flow may be needed, the present work designed three core models and three kinds of distribution plates to investigate the influence of lower plenum and distribution plates to thermohydraulics characteristics of the reactor core with CFD method use software FLUENT. Velocity field and maximum temperature of the core was simulated in each model at different mass flow rate.
Assessment of FLUENT Code as a Tool for SCW Heat Transfer Analysis
Authors: Farah Amjad , Harvel Glenn , Pioro Igor
Published: February 2014

Generation-IV SuperCritical Water-cooled Reactors (SCWRs) are expected to have high thermal efficiencies within the range of 45–50% owing to the reactor’s high pressures and outlet temperatures. The behavior of supercritical water however, is not well understood and most of the methods available to predict the effects of the heat transfer phenomena within the pseudocritical region are based on empirical one-directional correlations which do not capture the multi-dimensional effects and do not provide accurate results in regions such as the deteriorated heat transfer regime.

Computational Fluid Dynamics (CFD) is a numerical approach to model fluids in multidimensional space using the Navier-Stokes equations and databases of fluid properties to arrive at a full simulation of a fluid dynamics and heat transfer system.

In this work, the CFD code, FLUENT-12, is used with associated software such as Gambit and NIST REFPROP to predict the Heat Transfer Coefficients at the wall and corresponding wall temperature profiles inside vertical bare tubes with SuperCritical Water (SCW) as the cooling medium. The numerical results are compared with experimental data and 1-D models represented by existing empirical correlations.

Analysis of the individual heat-transfer regimes is conducted using an axisymmetric 2-D model of tubes of various lengths and composed of different nodalizations along the heated length. Wall temperatures and heat transfer coefficients were analyzed to select the best model for each region (below, at and above the pseudocritical region). Two turbulent models were used in the process: k-ε and k-ω, with variations in the sub-model parameters such as viscous heating, thermal effects, and low-Reynolds number correction.

Results of the analysis show a fit of ±10% for the wall temperatures using the SST k-ω model in the deteriorated heat transfer regime and less than ±5% for the normal heat transfer regime. The accuracy of the model is higher than any empirical correlation tested in the mentioned regimes, and provides additional information about the multidimensional effects between the bulk-fluid and wall temperatures.
Heat Transfer Correlation for Supercritical Carbon Dioxide Flowing in Vertical Bare Tubes
Authors: Gupta Sahil , Saltanov Eugene , Pioro Igor
Published: February 2014

Canada among many other countries is in pursuit of developing next generation (Generation IV) nuclear-reactor concepts. One of the main objectives of Generation-IV concepts is to achieve high thermal efficiencies (45–50%). It has been proposed to make use of SuperCritical Fluids (SCFs) as the heat-transfer medium in such Gen IV reactor design concepts such as SuperCritical Water-cooled Reactor (SCWR). An important aspect towards development of SCF applications in novel Gen IV Nuclear Power Plant (NPP) designs is to understand the thermodynamic behavior and prediction of Heat Transfer Coefficients (HTCs) at supercritical (SC) conditions.

To calculate forced convection HTCs for simple geometries, a number of empirical 1-D correlations have been proposed using dimensional analysis. These 1-D HTC correlations are developed by applying data-fitting techniques to a model equation with dimensionless terms and can be used for rudimentary calculations.

Using similar statistical techniques three correlations were proposed by Gupta et al. [1] for Heat Transfer (HT) in SCCO2. These SCCO2 correlations were developed at the University of Ontario Institute of Technology (Canada) by using a large set of experimental SCCO2 data (∼4,000 data-points) obtained at the Chalk River Laboratories (CRL) AECL. These correlations predict HTC values with an accuracy of ±30% and wall temperatures with an accuracy of ±20% for the analyzed dataset. Since these correlations were developed using data from a single source - CRL (AECL), they can be limited in their range of applicability. To investigate the tangible applicability of these SCCO2 correlations it was imperative to perform a thorough error analysis by checking their results against a set of independent SCCO2 tube data.

In this paper SCCO2 data are compiled from various sources and within various experimental flow conditions. HTC and wall-temperature values for these data points are calculated using updated correlations presented in [1] and compared to the experimental values. Error analysis is then shown for these datasets to obtain a sense of the applicability of these updated SCCO2 correlations.
Experimental Investigation on Liquid-Metal Flow Distribution in Insulating Manifold Under Uniform Magnetic Field
Authors: Ueki Yoshitaka , Miura Masato , Yokomine Takehiko , Kunugi Tomoaki
Published: February 2014

A presence of a strong external magnetic field can affect a flow distribution of a liquid-metal (LM) coolant in a fusion blanket, due to magnetohydrodynamic (MHD) effects. LM blankets have some manifolds, where the coolant flow from a single supply channel is distributed to multiple parallel channels. Since these manifolds have complex geometries, an interaction between induced axial electric currents and the magnetic field reorganizes the flow to be three-dimensional. A flow imbalance in such a complicated manifold affects heat removal performances, which is closely related to the blanket feasibility and safety. This study was performed to experimentally and numerically investigate a LM distribution in MHD flows in an electrically insulating manifold with changing the intensity and orientation of the magnetic field transverse to the flows. The flow passage employed in this study is a U-turn manifold consisting of an upward rectangular duct, a U-turn branching area, and two downward ducts with insulating walls. The gallium-indium-tin eutectic alloy (GaInSn) was employed as a working fluid. The present study shows that, as the magnetic field is applied more perpendicularly with respect to the U-turn, much amount of the fluid flows in the inner downward channel than that in the outer one.
Research of Seawater Effects on Thermal-Hydraulic Behavior at Severe Accident: 1 — Research Plan and Results of Preliminary Experiments
Authors: Liu Wei , Nagatake Taku , Takase Kazuyuki , Yoshida Hiroyuki , Nagase Fumihisa
Published: February 2014

The development of analytical method to predict and assess the current state of the reactor cores of Fukushima Daiichi nuclear power plant is required. Experimental researches are also required to obtain data to verify the analytical results and to understand the phenomena that are important to the accident progress evaluation.

In the Fukushima Daiichi nuclear power plant accident, seawater was injected into the reactors to cool down nuclear fuels. Core cooling with seawater has never been assumed and the effect of seawater on heat transfer in core is not clear. Then, effects of seawater on thermal-hydraulic behavior must be investigated to understand the phenomena occurred in the accident and to evaluate current state of the reactor cores.

In this series of research work, the effects of seawater on thermal-hydraulic behavior before and after degradation of the cores will be researched experimentally. Experimental results will be incorporated to numerical simulation codes to evaluate effects of seawater on the Fukushima Daiichi nuclear power plant accident. In the experimental research part, we have a plan performing two heat transfer experiments to evaluate thermal hydraulic performance of sea water and effects of salt precipitation. A precipitation state confirmation experiment is performed to obtain basic information required for the experiments with salt precipitation. In this paper, outline of the research plan is explained and the results of the precipitation state confirmation experiment is shown.
Predicting Thermal Mixing and Fatigue Inside Control Rod Guide Tubes
Authors: Lillberg Eric
Published: February 2014

The cracked control rods shafts found in two Swedish NPPs were subjected to thermal fatigue due to mixing of cold purge flow with hot bypass water in the upper part of the top tube on which the control rod guide tubes rests. The interaction between the jets formed at the bypass water inlets is the main source of oscillation resulting in low frequency downward motion of hot bypass water into the cold purge flow. This ultimately causes thermal fatigue in the control rod shaft in the region below the four lower bypass water inlets.

The transient analyses shown in this report were done to further investigate this oscillating phenomenon and compare to experimental measurements of water temperatures inside the control rod guide tube. The simulated results show good agreement with experimental data regarding all important variables for the estimation of thermal fatigue such as peak-to-peak temperature range, frequency of oscillation and duration of the temperature peaks.

The results presented in this report show that CFD using LES methodology and the open source toolbox OpenFOAM is a viable tool for predicting complex turbulent mixing flows and thermal loads.
Study on Design of Scaled Down Test Facilities for Investigation of Instabilities in Supercritical Water Reactor
Authors: Shankar Daya , Basu Dipankar N. , Pandey Manmohan
Published: February 2014

Supercritical Water Reactor (SCWR) proposes higher thermal efficiency and simpler plant design compared to modern Boiling Water Reactors. High pressure, temperature and power requirement in SCWR, however, escalates the cost of an experimental facility significantly. Present work, therefore, focuses on designing downscaled test facilities for stability analysis of SCWR. The facilities are conceptualized to model the European reference design of SCWR under both forced and natural circulation condition. R-134a is identified as the scaling fluids through fluid-to-fluid modeling, along with two others from literature. Similarity variables are obtained following two different approaches, starting from fundamental conservation equations. Dimensional and non-dimensional representations of important geometric, kinematic and dynamic parameters are evaluated and compared. Comparisons between two different approaches, as well as between forced and natural circulation have been presented for each scaling fluid.
AFCR and EC6: The Two Sister Products
Authors: Yee Frank , Kuran Sermet , Soulard Mike , Zhang Zhenhua
Published: February 2014

Candu Energy, based on its highly successful CANDU 6 (C6) reactors proven on four continents, is preparing to launch its C6 referenced Generation III products: Enhanced CANDU 6 (EC6), the natural uranium optimized, and Advanced Fuel CANDU Reactor (AFCR), the alternative fuel optimized, CANDU reactors. The AFCR design is based on the EC6 design with appropriate design changes to the reactor core to cater for the alternative fuel cycles and post Fukushima improvement.. The paper reviews the common design basis of these reactors and then discusses the unique advantages and market specific features for each product. The AFCR implementation plan for China is also discussed.
Thermal Conductivity Measurements for Simulated PWR Crud
Authors: Wang G. , Byers W. A. , Young M. Y. , Deshon J. , Karoutas Z. , Oelrich R. L.
Published: February 2014

This paper describes a laboratory test program to measure the thermal conductivity of corrosion product deposits on the surface of a Pressurized Water Reactor (PWR) fuel rod under a variety of thermal hydraulic conditions. This thermal conductivity information is necessary to allow more accurate predictions of fuel rod surface temperatures in the presence of fuel deposits, commonly known as crud.

In this paper, a four regime theory and methodology are proposed and utilized for crud thermal conductivity measurements and calculations. The relevant measurements were performed at the Westinghouse Advanced Loop Tester (WALT) facility, which is a single rod crud thermal-hydraulic test loop built at the Westinghouse Science and Technology Center (STC). This facility is described and then selected experiments and calculated results of this study are presented and discussed.
Review of the State of the Art on Startup Transients in Natural Circulation Boiling Water Systems
Authors: Lakshmanan S. P. , Pandey Manmohan
Published: February 2014

A proper understanding of the system behavior and other important parameters during startup of a Natural Circulation Boiling Water Reactor (NCBWR) is of primary importance in thermal hydraulic safety analysis. The use of natural circulation has introduced operational uncertainties, especially related to the startup phase of the reactor, when the system has to pass from single-phase to two-phase operation. Natural circulation systems may exhibit thermal-hydraulic instabilities under low-pressure low-power startup conditions. At low-pressures, a natural circulation loop typically has three operation ranges: single-phase stable region, two-phase unstable region and two-phase stable region. The instabilities in the region between single-phase and stable two-phase NC mode are mainly induced by the phenomenon of geysering in the heated channel and flashing in the riser section. The findings and understanding obtained through various experimental and analytical research is summarized in this paper. Numerical modeling of such low-pressure natural circulation phenomenon was also revisited and their start of the art is reported. The paper also discusses the various startup procedure proposed and employed for startup of NCBWRs.
Analysis of Accident Progression of Fukushima Daiichi NPPs With SAMPSON Code
Authors: Naitoh Masanori , Pellegrini Marco , Mizouchi Hideo , Suzuki Hiroaki , Okada Hidetoshi
Published: February 2014

The Fukushima Daiichi Nuclear Power Plant units 1, 2, and 3 had serious damages due to the huge earthquake and tsunami which occurred on March 11th 2011. Pressure transients in the reactor pressure vessels (RPVs) of the units 1, 2, and 3 were analyzed with the severe accident analysis code, SAMPSON for a few days from the scram until occurrence of depressurization. Since preliminary analysis results with the original SAMPSON showed difference from the measured data, the following phenomena were newly considered in the current analyses.

For unit 1: Damage of a source range monitor, which is one of in-core monitors.

For unit 2: Part load operation of the reactor core isolation cooling system.

For unit 3: Part load operation of the high pressure coolant injection system.

The calculation results showed fairly good agreements with the measured pressure data and showed RPV bottom damage for all the units resulting in falling of debris in the core region into the pedestal of the drywell.
Wave Propagation in the Hot Duct of VHTR
Authors: Liou Jim C. P. , Schultz Richard R.
Published: February 2014

In VHTR, helium from the reactor vessel is conveyed to a power conversion unit through a hot duct. In a hypothesized Depressurized Conduction Cooldown event where a rupture of the hot duct occurs, pressure waves will be initiated and reverberate in the hot duct. A numerical model is developed to quantify the transients and the helium mass flux through the rupture for such events. The flow path of the helium forms a closed loop but only the hot duct is modeled in this study. The lower plum of the reactor vessel and the steam generator are treated as specified pressure and/or temperature boundary to the hot duct. The model is based on the conservation principles of mass, momentum and energy, and on the equations of state for helium. The numerical solution is based on the method of characteristics with specified time intervals with a predictor and corrector algorithm. The rupture sub-model gives reasonable results. Transients induced by ruptures with break area equaling 20%, 10%, and 5% of the duct cross-sectional area are described.
A Preliminary 3D Steam Flow Analysis for CET Behavior During LSTF SBLOCA Experiment Using FLUENT Code
Authors: Irwanto Dwi , Satou Akira , Takeda Takeshi , Nakamura Hideo
Published: February 2014

A 3D steam flow within simulated fuel bundle of Large Scale Test Facility (LSTF), a PWR system simulator, has been investigated by Computational Fluid Dynamics (CFD) analysis with Ansys Fluent code to clarify influences of the steam flow on Core Exit Temperature (CET) response. A LSTF SBLOCA experiment with 1.5% hot leg break as the OECD/NEA ROSA-2 Project Test 3 was simulated by the CFD code to clarify relation between CET and fuel rod surface temperature. A portion of the LSTF core above the mixture level up to around CET sensors was modeled by taking into account high, medium and low heat-zone heater rod bundle, including internal structures such as end-box and upper core plate (UCP). Simulation of steady-state condition at a certain time when mixture level lowered to a certain position at around half of the core height (post-5) was carried out by considering relevant boundary conditions which were developed based on the LSTF Test 3 results. The calculation results revealed that inner structures of the core such as core spacer, end box and UCP indeed affect the CET due to heat transfer from hot steam to these cool structures. 3D flow mixing may also contribute to the final CET values and the delayed increase in the CET relative to the Peak Cladding Temperature (PCT) in the core.
Measurement of Three-Dimensional Time-Averaged Void Fraction Distribution in Rod Bundle in Air-Water System by X-Ray CT Technique
Authors: Katono Kenichi , Nukaga Jun , Nagayoshi Takuji , Yasuda Kenichi
Published: February 2014

We have been developing a void fraction distribution measurement technique using the three-dimensional (3D) time-averaged X-ray CT (computed tomography) system to understand two-phase flow behavior inside a fuel assembly for BWR (boiling water reactor) thermal hydraulic conditions of 7.2 MPa and 288 °C. Unlike CT images of a normal standstill object, we can obtain 3D CT images that are reconstructed from time-averaged X-ray projection data of the intermittent two-phase flow. We measured the 3D void fraction distribution in a vertical square (5 × 5) rod array that simulated a BWR fuel assembly in the air-water test. From the 3D time-averaged CT images, we confirmed that the void fraction at the center part of the channel box was higher than that near the channel box wall, and the local void fraction at the central region of a subchannel was higher than that at the gap region of the subchannel. A comparison of the volume-averaged void fractions evaluated by the developed X-ray CT system with those evaluated by a differential pressure transducer in a void fraction range from 0.05 to 0.40 showed satisfactory agreement within a difference of 0.03.
Shielding Calculation Research Based on Point-Kernel Integral Method
Authors: Yin Yuhao , Ding Sizhong , Huang Yichao
Published: February 2014

Point-kernel integral method, which has been verified by authorities, is widely used in radiation shielding calculations. In this article, we introduced point-kernel integral method in detail. Calculations have been performed for the radiation shielding design of TEG (gaseous waste processing system) system of one Chinese CRP1000 reactor, using the point-kernel integral codes QAD-CGA and Microshield 9. Dose results calculated by the two representative codes are compared from several aspects. We also focus our discussion on the impact of buildup factors that are fitted by different kinds of methods, which are the most important parameters in point-kernel integral method.

From the discussion in this article, we can draw the conclusions that 1)both of the two codes are of accurate and consistent calculation results, shielding calculation results are convinced; Microshield 9 proved to be reasonably reliable compared to results of traditional code QAD-CGA; 2) compared with QAD-CGA, Microshield 9 uses the latest database and simpler input form, but cannot calculate more than one source at one time; 3) buildup factor plays the most important role in point-kernel integral method; the two codes adopt different kinds of buildup factor fitting method; for the difference of dose calculation results using buildup factor or not, QAD-CGA is a little higher than Microshield 9 because of the different buildup factor calculation principles; 4) besides, the buildup factor reference material is advised to use either the last or the most dominant shielding.
The Document Management of Major Scientific Projection of Fusion
Authors: Wang Shenji , Fu Xiaofeng , Ye Minyou , Li Jia , Gong Meijing
Published: February 2014

As we all know the nuclear energy is becoming more and more important in our current life, as well in the future. Considering the radiation protection, nuclear safety, security, fusion attracts more and more view of scientists compared with fission. International Thermonuclear Experimental Reactor (ITER) is the world’s biggest energy research project, aiming to prove the feasibility of fusion power as a possible source of safe, sustainable and abundant energy. China together with EU, India, Japan, the Russian Federation, South Korea and the USA are working together on this major research facility. It is an example of international scientific collaboration on an unprecedented scale that will provide the link between plasma physics and engineering and future commercial fusion-based power plants. ITER design and construction have resulted in new issue that how the seven members collaborate all over the earth. So the Document Management has become the indispensable part. This article according to the document management of ITER, as we all know, the IDM system analysis the key point of scan and search, document operating, security settings, process controlling and other information.

In order to progress the document management of major scientific project of fusion for China, for example the China Fusion Engineering Test Reactor (CFETR), the first step we should learn from IDM of ITER. Then try to solve the current problem of IDM, such as the response speed, operating difficulty and so on.

This paper gives a conceptual design solution for the document management system of major scientific projection like CFETR including document storage, document classification and nomenclature, access control, workflow and roles setting of the system.
Mechanical Performances of ITER In-Vessel Coil’s Conductor
Authors: Jin Huan , Yu Wu , Long Feng , Yu Min , Han Qiyang , Zhai Yuhu
Published: February 2014

The design and R&D for ITER In-Vessel Coils (IVCs) is being deployed. The concerned issue of “Edge Localized Modes” (ELMs) and “Vertical Stabilization” (VS) of the ITER plasma can be addressed by the implemented IVCs. The ELM and VS coils will be installed in the vessel just behind the blanket shield modules to reach the requirement of keeping strong coupling with the plasma. The 59mm Stainless Steel Jacketed Mineral Insulated Conductor (SSMIC) using MgO as the insulation is being designed for the IVCs to resist the special challenges, including the nuclear radiation, high temperature, electromagnetic and thermal fatigue. It is necessary to take the mechanical performances of the SSMIC and the feasibility of fabrication techniques into consideration of the R&D program. The mechanical performances of the SSMIC close to the actual work conditions, including the three point bend modulus, three point bend cyclical performance and the cyclical performance with a U-bend sample of the SSMIC prototypes have been investigated and the results are presented in this paper.
Nanofluid Boiling Heat Transfer and Critical Heat Flux Enhancement: Mechanism to Be Revealed
Authors: Wu Junmei , Zhao Jiyun , Wang Yun
Published: February 2014

As a novel strategy to improve heat transfer characteristics of fluids by the addition of solid particles with diameters below 100 nm, nanofluids exhibits unprecedented heat transfer properties and are being considered as potential working fluids to be used in high heat flux systems such as nuclear reactors, electronic cooling systems and solar collectors. The present paper reviews the state-of-the-art studies on nanofluid boiling heat transfer performance and critical heat flux (CHF) enhancement. It is found that some results on nanofluids boiling heat transfer performance are inconsistent or contradictory in data published. The knowledge on the mechanism of nanofluids boiling CHF enhancement is insufficient. Bubble dynamics of nanofluids boiling is suggested to be investigated to identify the exact contributions of solid surface modifications and suspended nanoparticles to CHF enhancement in nanofluids boiling heat transfer.
Physiological Response, Time–Motion Characteristics, and Reproducibility of Various Speed-Endurance Drills in Elite Youth Soccer Players: Small-Sided Games Versus Generic Running
Authors: Ade Jack D. , Harley Jamie A. , Bradley Paul S.
Published: February 2014

Purpose:

To quantify the physiological responses, time–motion characteristics, and reproducibility of various speed-endurance-production (SEP) and speed-endurance-maintenance (SEM) drills.

Methods:

Sixteen elite male youth soccer players completed 4 drills: SEP 1 v 1 small-sided game (SSG), SEP running drill, SEM 2 v 2 SSG, and SEM running drill. Heart-rate response, blood lactate concentration, subjective rating of perceived exertion (RPE), and time–motion characteristics were recorded for each drill.

Results:

The SEP and SEM running drills elicited greater (P < .05) heart-rate responses, blood lactate concentrations, and RPE than the respective SSGs (ES 1.1–1.4 and 1.0–3.2). Players covered less (P < .01) total distance and high-intensity distance in the SEP and SEM SSGs than in the respective running drills (ES 6.0–22.1 and 3.0–18.4). Greater distances (P < .01) were covered in high to maximum acceleration/deceleration bands during the SEP and SEM SSGs than the respective running drills (ES 2.6–4.6 and 2.3–4.8). The SEP SSG and generic running protocols produced greater (P < .05) blood lactate concentrations than the respective SEM protocols (ES 1.2–1.7). Small to moderate test–retest variability was observed for heart-rate response (CV 0.9–1.9%), RPE (CV 2.9–5.7%), and blood lactate concentration (CV 9.9–14.4%); moderate to large test–retest variability was observed for high-intensity-running parameters (CV > 11.3%) and the majority of accelerations/deceleration distances (CV > 9.8%) for each drill.

Conclusions:

The data demonstrate the potential to tax the anaerobic energy system to different extents using speed-endurance SSGs and that SSGs elicit greater acceleration/deceleration load than generic running drills.
Assessment of Bilateral Asymmetry in Cycling Using a Commercial Instrumented Crank System and Instrumented Pedals
Authors: Bini Rodrigo R. , Hume Patria A.
Published: February 2014

The accuracy of commercial instrumented crank systems for symmetry assessment in cycling has not been fully explored. Therefore, the authors’ aims were to compare peak crank torque between a commercial instrumented crank system and instrumented pedals and to assess the effect of power output on bilateral asymmetries during cycling. Ten competitive cyclists performed an incremental cycling test to exhaustion. Forces and pedal angles were recorded using right and left instrumented pedals synchronized with crank-torque measurements using an instrumented crank system. Differences in right (dominant) and left (nondominant) peak torque and asymmetry index were assessed using effect sizes. In the 100- to 250-W power-output range, the instrumented pedal system recorded larger peak torque (dominant 55–122%, nondominant 23–99%) than the instrumented crank system. There was an increase in differences between dominant and nondominant crank torque as power output increased using the instrumented crank system (7% to 33%) and the instrumented pedals (9% to 66%). Lower-limb asymmetries in peak torque increased at higher power-output levels in favor of the dominant leg. Limitations in design of the instrumented crank system may preclude the use of this system to assess peak crank-torque symmetry.
Draft Genome Sequence of Ralstonia pickettii AU12-08, Isolated from an Intravascular Catheter in Australia
Authors: Zhang Li , Morrison Mark , Rickard Claire M.
Published: February 2014

Ralstonia pickettii
is a nonfermenting Gram-negative bacillus that creates a significant problem in clinical settings, as it is a widespread cause of nosocomial infections. Here, we report the draft genome sequence of
R. pickettii
AU12-08, isolated from an intravascular catheter tip.
Draft Genome Sequence of the Filamentous Cyanobacterium
Leptolyngbya
sp. Strain Heron Island J, Exhibiting Chromatic Acclimation
Authors: Paul Robin , Jinkerson Robert E. , Buss Kristina , Steel Jason , Mohr Remus , Hess Wolfgang R. , Chen Min , Fromme Petra
Published: February 2014

Leptolyngbya
sp. strain Heron Island is a cyanobacterium exhibiting chromatic acclimation. However, this strain has strong interactions with other bacteria, making it impossible to obtain axenic cultures for sequencing. A protocol involving an analysis of tetranucleotide frequencies, G+C content, and BLAST searches has been described for separating the cyanobacterial scaffolds from those of its cooccurring bacteria.
Complete Genome Sequence of Mycobacterium avium subsp.
paratuberculosis
, Isolated from Human Breast Milk
Authors: Bannantine John P. , Li Lingling , Mwangi Michael , Cote Rebecca , Raygoza Garay Juan A. , Kapur Vivek
Published: February 2014

Mycobacterium avium
subsp.
paratuberculosis
is the etiologic agent of Johne's disease in ruminants and has also been associated with human Crohn's disease. We report the complete genome sequence of
M. avium
subsp.
paratuberculosis
, isolated from the breast milk of a Crohn's disease patient. This sequence has high identity with characterized strains recovered from cattle.
Complete Genome Sequence of the WHO International Standard for HIV-1 RNA Determined by Deep Sequencing
Authors: Gall Astrid , Morris Clare , Kellam Paul , Berry Neil
Published: February 2014

The World Health Organization (WHO) International Standard for HIV-1 RNA nucleic acid assays was characterized by complete genome deep sequencing analysis. The entire coding sequence and flanking long terminal repeats (LTRs), including minority species, were assigned subtype B. This information will aid the design, development, and evaluation of HIV-1 RNA amplification assays.
Reactive arthritis induced by intravesical BCG therapy for bladder cancer
Authors: Ben Abdelghani Kaouther , Fazaa Alia , Souabni Leila , Zakraoui Leith
Published: February 2014

Cancers of the bladder could be treated with intravesical instillation of BCG therapy. This treatment could lead to some complications. Osteoarticular ones are relatively uncommon. We describe an original observation, illustrating the development of reactive arthritis after intravesical BCG therapy. A 60-year-old man was followed for a T1G3 transitional papillary carcinoma of the bladder and was treated with intravesical BCG immunotherapy. Within the sixth intravesical instillation, he presented with polyarthritis confirmed by musculoskeletal ultrasound. The erythrocyte sedimentation rate was 100 mm without leukocytosis. The viral and bacterial serologies and immunological tests were negative. The ophthalmological examination revealed left conjunctivitis. Treatment with non-steroidal anti-inflammatory drugs was started, combined with the discontinuation of the intravesical instillation. No recurrence has been reported with a current decline of 2 years.
Excellent postoperative analgesia with the addition of hyaluronidase to lignocaine for subcostal TAP block used in conjunction with systemic analgesia for laparoscopic cholecystectomy
Authors: Johnson Mark Zachary , O'Connor Therese C
Published: February 2014

Subcostal transversus abdominis plane (TAP) blocks provide good postoperative analgesia for laparoscopic cholecystectomies. We hypothesised that adding hyaluronidase may improve the efficacy of this technique by increasing spread of the local anaesthetic (LA). In this case, we performed a bilateral ultrasound-guided subcostal TAP block using lignocaine (40 mL 1%) with hyaluronidase (75 IU/mL) for postoperative analgesia following elective laparoscopic cholecystectomy. It was used in combination with intraoperative morphine, diclofenac and paracetamol. Regular paracetamol was administered postoperatively. We monitored serial serum lignocaine levels and recorded the patient's visual analogue scale (VAS) pain scores postoperatively. We found that the patient experienced excellent analgesia throughout the postoperative period and that the serum lignocaine levels did not exceed the therapeutic range.
Laboratory test ordering and results management systems: a qualitative study of safety risks identified by administrators in general practice
Authors: Bowie Paul , Halley Lyn , McKay John
Published: February 2014

Objective

To explore experiences and perceptions of frontline administrators involved in the systems-based management of laboratory test ordering and results handling in general medical practice.

Design

Qualitative using focus group interviews.

Setting

West of Scotland general medical practices in three National Health Service (NHS) territorial board areas.

Participants

Convenience samples of administrators (receptionists, healthcare assistants and phlebotomists).

Methods

Transcript data were subjected to content analysis.

Results

A total of 40 administrative staff were recruited. Four key themes emerged: (1) system variations and weaknesses (eg, lack of a tracking process is a known risk that needs to be addressed). (2) Doctor to administrator communication (eg, unclear information can lead to emotional impacts and additional workload). (3) Informing patients of test results (eg, levels of anxiety and uncertainty are experienced by administrators influenced by experience and test result outcome) and (4) patient follow-up and confidentiality (eg, maintaining confidentiality in a busy reception area can be challenging). The key findings were explained in terms of sociotechnical systems theory.

Conclusions

The study further confirms the safety-related problems associated with results handling systems and adds to our knowledge of the communication and psychosocial issues that can affect the health and well-being of staff and patients alike. However, opportunities exist for practices to identify barriers to safe care, and plan and implement system improvements to accommodate or mitigate the potential for human error in this complex area.
Carotid artery stenting in nonagenarians: are there benefits in surgically treating this high risk population?
Authors: Wach Michael M , Dumont Travis M , Shakir Hakeem J , Snyder Kenneth V , Hopkins L Nelson , Levy Elad I , Siddiqui Adnan H
Published: February 2014

Background

Carotid angioplasty and stenting (CAS) is considered desirable treatment for patients at high risk for carotid endarterectomy. Despite a growing elderly population, scant data exist on CAS in nonagenarians. Nonagenarians represent a high risk population for open and endovascular interventions due to unique anatomic and physiologic characteristics presenting significant challenges to anesthesiologists and surgeons. Studies have quantified that symptomatic and asymptomatic patients should survive 2 and 5 years, respectively, to gain benefit from revascularization; thus doubt exists on the value of CAS in nonagenarian patients because of their extreme age and unique risk factors. We therefore evaluated CAS safety and efficacy in our hospital's nonagenarian population.

Methods

CAS cases performed in patients aged ≥90 years between April 2005 and January 2013 were retrospectively examined. Relevant demographic and medical data were reviewed. Rates of perioperative complications and complications until end of follow-up (including stroke, myocardial infarction, death) were compiled.

Results

Among 21 nonagenarian cases of stent placement performed in 20 patients (11 symptomatic, nine asymptomatic), two patients suffered perioperative stroke after undergoing CAS and one died during the perioperative period. 50% of symptomatic patients were alive at 19 months; 50% of asymptomatic patients were alive at 47 months.

Conclusions

CAS in nonagenarian patients carried increased risk of perioperative ischemic events, compared with contemporary trial results in symptomatic and asymptomatic patients. Further, mean survival time postprocedure fell short of guidelines for receiving procedural benefit. Although larger scale multicenter research is needed, we recommend careful consideration of overall health status when contemplating stenting in nonagenarians.
Nonlinear integro-differential Einstein’s field equations from nonstandard Lagrangians
Authors: El-Nabulsi Rami Ahmad
Published: February 2014

Given a manifold [Formula: see text] described by coordinates {xμ} and a space–time metric gμν on [Formula: see text] describing the gravitational field whose standard action is the Einstein–Hilbert action, we observe that if the action functional of spinor fields {Ψ(S)(x)}, S = 1, 2, …, N representing the matter and gauge fields holds a nonstandard exponential Lagrangian, the modified Einstein field equations acquire nonlinear partial integro-differential forms where both spinor and gravitational fields come out together.
When do pieces determine the whole? Extreme marginals of a completely positive map
Authors: Haapasalo E. , Heinosaari T. , Pellonpää J.-P.
Published: February 2014

We will consider completely positive maps defined on tensor products of von Neumann algebras and taking values in the algebra of bounded operators on a Hilbert space and particularly certain convex subsets of the set of such maps. We show that when one of the marginal maps of such a map is an extreme point, then the marginals uniquely determine the map. We will further prove that when both of the marginals are extreme, then the whole map is extreme. We show that this general result is the common source of several well-known results dealing with, e.g., jointly measurable observables. We also obtain new insight especially in the realm of quantum instruments and their marginal observables and channels.
QUANTUM PARTICLE SWARM OPTIMIZATION CLASSIFICATION ALGORITHM AND ITS APPLICATIONS
Authors: LIU RUOCHEN , ZHANG PING , JIAO LICHENG
Published: February 2014

Data processing in high-dimensional spaces is a challenging task. In order to effectively classify the data in a high-dimensional space, a quantum particle swarm optimization classification algorithm (QPSOCA) for high-dimensional datasets is proposed in this paper. In QPSOCA, an uncorrelated discriminant analysis algorithm is utilized to reduce the dimension of the data, which is implemented automatically and no extra parameters are needed. In addition, to avoid the randomness of the swarm and improve the convergence speed, quantum computation is introduced into particle swarm optimization (PSO). In the experimental section, a detailed comparison of three different combinatorial optimization methods is given to demonstrate the efficiency of the proposed algorithm. Comparative experiments show that the proposed algorithm can improve the classification accuracy.
CLUSTER ALGEBRA AND COMPLEX VOLUME OF ONCE-PUNCTURED TORUS BUNDLES AND 2-BRIDGE LINKS
Authors: HIKAMI KAZUHIRO , INOUE REI
Published: February 2014

We propose a method to compute complex volume of 2-bridge link complements. Our construction sheds light on a relationship between cluster variables with coefficients and canonical decompositions of link complements.
The Cauchy problem in hybrid metric-Palatini f(X)-gravity
Authors: Capozziello Salvatore , Harko Tiberiu , Lobo Francisco S. N. , Olmo Gonzalo J. , Vignolo Stefano
Published: February 2014

The well-formulation and the well-posedness of the Cauchy problem are discussed for hybrid metric-Palatini gravity, a recently proposed modified gravitational theory consisting of adding to the Einstein–Hilbert Lagrangian an f(R)-term constructed à la Palatini. The theory can be recast as a scalar-tensor one predicting the existence of a light long-range scalar field that evades the local Solar System tests and is able to modify galactic and cosmological dynamics, leading to the late-time cosmic acceleration. In this work, adopting generalized harmonic coordinates, we show that the initial value problem can always be well-formulated and, furthermore, can be well-posed depending on the adopted matter sources.
A survey of migration mechanisms of virtual machines
Authors: Medina Violeta , García Juan Manuel
Published: February 2014

In the virtualization area, replication has been considered as a mechanism to provide high availability. A high-availability system should be active most of the time, and this is the reason that its design should consider almost zero downtime and a minimal human intervention if a recovery process is demanded. Several migration and replication mechanisms have been developed to provide high availability inside virtualized environments. In this article, a survey of migration mechanisms is reported. These approaches are classified in three main classes: process migration, memory migration, and suspend/resume migration.