Experimental Study on the Burning Behavior of Pool Fires in Rooms with Different Wall Linings

DEFF Research Database (Denmark)

Poulsen, Annemarie; Jomaas, Grunde

2011-01-01

An experimental test series, comprising 10 experiments with varying pool sizes, lining materials and amounts of liquid burning, was conducted under free burn and room burn conditions. The thermal feedback from the enclosure (ISO 9705 Room Corner Test facility) enhanced the burning rate of the poo...... in the shortest time. Given the profound difference between the enclosure tests and the free burn tests and also between enclosure tests with different linings, it is recommended to show great caution if free burn tests are to be used in design fire scenarios....

Landscape factors and hydrology influence mercury concentrations in wading birds breeding in the Florida Everglades, USA.

Science.gov (United States)

Herring, Garth; Eagles-Smith, Collin A; Ackerman, Joshua T; Gawlik, Dale E; Beerens, James M

2013-08-01

The hydrology of wetland ecosystems is a key driver of both mercury (Hg) methylation and waterbird foraging ecology, and hence may play a fundamental role in waterbird exposure and risk to Hg contamination. However, few studies have investigated hydrological factors that influence waterbird Hg exposure. We examined how several landscape-level hydrological variables influenced Hg concentrations in great egret and white ibis adults and chicks in the Florida Everglades. The great egret is a visual "exploiter" species that tolerates lower prey densities and is less sensitive to hydrological conditions than is the white ibis, which is a tactile "searcher" species that pursues higher prey densities in shallow water. Mercury concentrations in adult great egrets were most influenced by the spatial region that they occupied in the Everglades (higher in the southern region); whereas the number of days a site was dry during the previous dry season was the most important factor influencing Hg concentrations in adult ibis (Hg concentrations increased with the number of days dry). In contrast, Hg concentrations in egret chicks were most influenced by calendar date (increasing with date), whereas Hg concentrations in ibis chicks were most influenced by chick age, region, and water recession rate (Hg concentrations decreased with age, were higher in the southern regions, and increased with positive water recession rates). Our results indicate that both recent (preceding two weeks) hydrological conditions, and those of the prior year, influence Hg concentrations in wading birds. Further, these results suggest that Hg exposure in wading birds is driven by complex relationships between wading bird behavior and life stage, landscape hydrologic patterns, and biogeochemical processes. Published by Elsevier B.V.

Predicting foraging wading bird populations in Everglades National Park from seasonal hydrologic statistics under different management scenarios

Science.gov (United States)

Kwon, Hyun-Han; Lall, Upmanu; Engel, Vic

2011-09-01

The ability to map relationships between ecological outcomes and hydrologic conditions in the Everglades National Park (ENP) is a key building block for their restoration program, a primary goal of which is to improve conditions for wading birds. This paper presents a model linking wading bird foraging numbers to hydrologic conditions in the ENP. Seasonal hydrologic statistics derived from a single water level recorder are well correlated with water depths throughout most areas of the ENP, and are effective as predictors of wading bird numbers when using a nonlinear hierarchical Bayesian model to estimate the conditional distribution of bird populations. Model parameters are estimated using a Markov chain Monte Carlo (MCMC) procedure. Parameter and model uncertainty is assessed as a byproduct of the estimation process. Water depths at the beginning of the nesting season, the average dry season water level, and the numbers of reversals from the dry season recession are identified as significant predictors, consistent with the hydrologic conditions considered important in the production and concentration of prey organisms in this system. Long-term hydrologic records at the index location allow for a retrospective analysis (1952-2006) of foraging bird numbers showing low frequency oscillations in response to decadal fluctuations in hydroclimatic conditions. Simulations of water levels at the index location used in the Bayesian model under alternative water management scenarios allow the posterior probability distributions of the number of foraging birds to be compared, thus providing a mechanism for linking management schemes to seasonal rainfall forecasts.

Excavations in 2014 at Wade Street, Bristol - a documentary and archaeological analysis

OpenAIRE

Nick Corcos; Kamal Badreshany; Alejandra Gutiérrez; Rachel Heaton; Lorrain Higbee; Sarah Newns; Rachel Tyson

2017-01-01

A staged programme of historical research and archaeological fieldwork, involving a desk-based assessment in 2000 (Smith and Erskine 2000), an evaluation in 2013 (Mason 2013), and an excavation followed by a watching brief in 2014, the latter two by Avon Archaeology Ltd, was undertaken in order to mitigate the archaeological impact of a proposed residential development on a site of 1,260m² at the corner and on the north-west side of Little Anne Street and Wade Street, St Jude’s, Bristol. The ...

Preliminary Use of Uric Acid as a Biomarker for Wading Birds on Everglades Tree Islands, Florida, United States

Science.gov (United States)

Bates, Anne L.; Orem, William H.; Newman, Susan; Gawlik, Dale E.; Lerch, Harry E.; Corum, Margo D.; Van Winkle, Monica

2010-01-01

Concentrations of organic biomarkers and concentrations of phosphorus in soil cores can potentially be used as proxies for historic population densities of wading birds on tree islands in the Florida Everglades. This report focuses on establishing a link between the organic biomarker uric acid found in wading bird guano and the high phosphorus concentrations in tree island soils in the Florida Everglades. Uric acid was determined in soil core sections, in surface samples, and in bird guano by using a method of high-performance liquid chromatography-mass spectrometry (HPLC-MS) developed for this purpose. Preliminary results show an overall correlation between uric acid and total phosphorus in three soil cores, with a general trend of decreasing concentrations of both uric acid and phosphorus with depth. However, we have also found no uric acid in a soil core having high concentrations of phosphorus. We believe that this result may be explained by different geochemical circumstances at that site.

Refurbishment of Pakistan research reactor (PARR-1) for stainless steel lining of the reactor pool

International Nuclear Information System (INIS)

Salahuddin, A.; Israr, M.; Hussain, M.

2002-01-01

Pakistan Research Reactor-1 (PARR-1) is a pool-type research reactor. Reactor aging has resulted in the increase of water seepage from the concrete walls of the reactor pool. To stop the seepage, it was decided to augment the existing pool walls with an inner lining of stainless steel. This could be achieved only if the pool walls could be accessed unhindered and without excessive radiation doses. For this purpose a partial decommissioning was done by removing all active core components including standard/control fuel elements, reflector elements, beam tubes, thermal shield, core support structure, grid plate and the pool's ceramic tiles, etc. An overall decommissioning program was devised which included procedures specific to each item. This led to the development of a fuel transport cask for transportation, and an interim fuel storage bay for temporary storage of fuel elements (until final disposal). The safety of workers and the environment was ensured by the use of specially designed remote handling tools, appropriate shielding and pre-planned exposure reduction procedures based on the ALARA principle. During the implementation of this program, liquid and solid wastes generated were legally disposed of. It is felt that the experience gained during the refurbishment of PARR-1 to install the stainless steel liner will prove useful and better planning and execution for the future decommissioning of PARR-1, in particular, and for other research reactors like PARR-2 (27 kW MNSR), in general. Furthermore, due to the worldwide activities on decommissioning, especially those communicated through the IAEA CRP on 'Decommissioning Techniques for Research Reactors', the importance of early planning has been well recognized. This has made possible the implementation of some early steps like better record keeping, rehiring of trained manpower, and creation of interim and final waste storage. (author)

Pooled analysis of phase II trials evaluating weekly or conventional cisplatin as first-line therapy for advanced urothelial carcinoma

DEFF Research Database (Denmark)

Maughan, Benjamin L; Agarwal, Neeraj; Hussain, Syed A

2013-01-01

Weekly gemcitabine with GC every 3-4 weeks is considered conventional first-line chemotherapy for advanced urothelial carcinoma (UC). Weekly split-dose cisplatin with wGC might be less toxic and have similar activity, but has not been compared with GC. We pooled published phase II trials of GC an...

Wading bird guano enrichment of soil nutrients in tree islands of the Florida Everglades

Energy Technology Data Exchange (ETDEWEB)

Irick, Daniel L. [University of Florida, Soil and Water Science Department, Tropical Research and Education Center, 18905 SW 280th St., Homestead, FL 33031 (United States); Gu, Binhe [University of Florida, Soil and Water Science Department, 2181 McCarty Hall, Gainesville, FL 32611 (United States); Li, Yuncong C., E-mail: yunli@ufl.edu [University of Florida, Soil and Water Science Department, Tropical Research and Education Center, 18905 SW 280th St., Homestead, FL 33031 (United States); Inglett, Patrick W. [University of Florida, Soil and Water Science Department, 2181 McCarty Hall, Gainesville, FL 32611 (United States); Frederick, Peter C. [University of Florida, Department of Wildlife Ecology and Conservation, 110 Newins-Ziegler Hall, PO Box 110430, Gainesville, FL 32611 (United States); Ross, Michael S. [Florida International University, Department of Earth and Environment, Southeast Environmental Research Center, 11200 SW 8th St, Miami, FL 33199 (United States); Wright, Alan L. [University of Florida, Soil and Water Science Department, Everglades Research and Education Center, 3200 E. Palm Beach Rd., Belle Glade, FL 33430 (United States); Ewe, Sharon M.L. [Ecology and Environment, Inc., 12300 South Shore Blvd, Wellington, FL 33414 (United States)

2015-11-01

Differential distribution of nutrients within an ecosystem can offer insight of ecological and physical processes that are otherwise unclear. This study was conducted to determine if enrichment of phosphorus (P) in tree island soils of the Florida Everglades can be explained by bird guano deposition. Concentrations of total carbon, nitrogen (N), and P, and N stable isotope ratio (δ{sup 15}N) were determined on soil samples from 46 tree islands. Total elemental concentrations and δ{sup 15}N were determined on wading bird guano. Sequential chemical extraction of P pools was also performed on guano. Guano contained between 53.1 and 123.7 g-N kg{sup −1} and 20.7 and 56.7 g-P kg{sup −1}. Most of the P present in guano was extractable by HCl, which ranged from 82 to 97% of the total P. Total P of tree islands classified as having low or high P soils averaged 0.71 and 40.6 g kg{sup −1}, respectively. Tree island soil with high total P concentration was found to have a similar δ{sup 15}N signature and total P concentration as bird guano. Phosphorus concentrations and δ{sup 15}N were positively correlated in tree island soils (r = 0.83, p < 0.0001). Potential input of guano with elevated concentrations of N and P, and {sup 15}N enriched N, relative to other sources suggests that guano deposition in tree island soils is a mechanism contributing to this pattern. - Highlights: • Tree island soil P concentration and δ{sup 15}N values exceed other Everglades soils. • Characteristics of Everglades tree island soil may indicate guano deposition. • Deposition of stable guano P can exceed other P sources to tree island soil.

77 FR 16196 - Delaying the Compliance Date for Certain Requirements of the Regulations Implementing Titles II...

Science.gov (United States)

2012-03-20

... be received. The constraints imposed by the Regulations.gov/FDMS system do not apply to U.S. postal... pools, wading pools, and spas in compliance with the 2010 Standards. The proposed extension would run...

Roe v. Wade, the next twenty-five years.

Science.gov (United States)

Kissling, F

1998-01-01

There is little left to be said about abortion in the US; most Americans are either bored with the issue or the issue has simply lost its immediacy. The world today is certainly different from the 1970s, when the US Supreme Court issued its Roe vs. Wade decision. That era was marked by societal and economic generosity manifest by greater acceptance of civil rights, liberal sexual mores, acceptance of divorce, ignorance of infertility, and a focus on alleviating the readily apparent suffering of women made desperate by an unwanted pregnancy. In the 25 intervening years, abortion has remained legal even as the US has become more conservative. It may be, therefore, that pro-choices forces are safe enough to attempt to regain the moral edge and lead the way out of the abortion wars. In order to do this, the values that informed early commitment to women's right to make the abortion decision must finally be clearly expressed, explained, and advocated. Also, pro-choice groups must initiate a more meaningful public dialogue about the morality of abortion and offer answers to the hard questions such as whether it is not better to encourage teenagers to talk to their parents about an unwanted pregnancy, what is the moral significance of developing life, is viability a significant threshold, are there better and worse reasons for abortion, and are some pro-abortion arguments morally dubious. While some may consider this course of action threatening, the visionary leadership that is desperately needed involves addressing both the underlying values and hard questions.

Clean-up system for pool water in pressure suppression chamber and operation method therefor

Energy Technology Data Exchange (ETDEWEB)

Hirabayashi, Kentaro; Kinoshita, Shoichiro

1996-09-17

Pool water in a pressure suppression chamber of a BWR type reactor is sucked by a pump of an after-heat removing system. The pool water pressurized here is sent to the pressure suppression chamber by way of a heat exchanger and a test line backwarding pipeline to stir the pool water in the pressure suppression chamber. Further, the pool water pressurized by the pump is sent to the pressure suppression chamber by way of a filtration desalting device and an exit pipe to purify the pool water. Upon cleaning of pipelines before the start of a periodical test, the pool water sucked by the pump is sent to the filtration desalting device and recovered to the pressure suppression chamber. This can reduce the amount of impurities carried to the suppression chamber. After the cleaning of the pipelines, pool water is passed through the test line backwarding pipeline, so that the pool water can be stirred at the same time. (I.N.)

Security cost allocation under combined bilateral-pool market dispatch

International Nuclear Information System (INIS)

Abdullah, M.P.; Hassan, M.Y.; Hussin, F.

2008-01-01

Most electricity markets around the world are a combination of bilateral and pool markets, such as NordPool and NYPOOL. In these models, market participants bid into the pool and also make bilateral contracts with each other. This paper addressed the issue of congestion management and security cost allocation in a power pool market model. The basic idea of security cost allocation is to divide the incurred security cost due to congestion relief into pool and bilateral market based on their flow contribution to the congested line. A newly proposed security cost allocation strategy of the combined bilateral-pool market was also presented along with case studies using IEEE-14 bus system that tested the proposed method. Using the proposed method, it was shown that security costs are allocated to market participants at different prices which reflect the load contribution to the security problem. This solves the problem of the uniform security cost allocation in a pure pool market system having uniform pricing, and provides a proper security signal to market participants. 11 refs., 3 tabs., 4 figs

Mitigated subsurface transfer line leak resulting in a surface pool

Energy Technology Data Exchange (ETDEWEB)

SCOTT, D.L.

1999-02-08

This analysis evaluates the mitigated consequences of a potential waste transfer spill from an underground pipeline. The spill forms a surface pool. One waste composite, a 67% liquid, 33% solid, from a single shell tank is evaluated. Even drain back from a very long pipeline (50,000 ft), does not pose dose consequences to the onsite or offsite individual above guideline values.

Mitigated subsurface transfer line leak resulting in a surface pool

International Nuclear Information System (INIS)

SCOTT, D.L.

1999-01-01

This analysis evaluates the mitigated consequences of a potential waste transfer spill from an underground pipeline. The spill forms a surface pool. One waste composite, a 67% liquid, 33% solid, from a single shell tank is evaluated. Even drain back from a very long pipeline (50,000 ft), does not pose dose consequences to the onsite or offsite individual above guideline values

13 CFR 120.611 - Pools backing Pool Certificates.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Pools backing Pool Certificates. 120.611 Section 120.611 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Secondary Market Certificates § 120.611 Pools backing Pool Certificates. (a) Pool characteristics. As set...

Distributed Technologies in a Data Pool

Science.gov (United States)

Keiser, K.; Conover, H.; Graves, S.; He, Y.; Regner, K.; Smith, M.

2004-12-01

A Data Pool is an on-line repository providing interactive and programmatic access to data products through a variety of services. The University of Alabama in Huntsville has developed and deployed such a Data Pool in conjunction with the DISCOVER project, a collaboration with NASA and Remote Sensing Systems. DISCOVER provides long-term ocean and climate data from a variety of passive microwave satellite instruments, including such products as sea-surface temperature and wind, air temperature, atmospheric water vapor, cloud water and rain rate. The Data Pool provides multiple methods to access and visualize these products, including conventional HTTP and FTP access, as well as data services that provide for enhanced usability and interoperability, such as GridFTP, OPeNDAP, OpenGIS-compliant web mapping and coverage services, and custom subsetting and packaging services. This paper will focus on the distributed service technologies used in the Data Pool, which spans heterogeneous machines at multiple locations. For example, in order to provide seamless access to data at multiple sites, the Data Pool provides catalog services for all data products at the various data server locations. Under development is an automated metadata generation tool that crawls the online data repositories regularly to dynamically update the Data Pool catalog with information about newly generated data files. For efficient handling of data orders across distributed repositories, the Data Pool also implements distributed data processing services on the file servers where the data resides. Ontologies are planned to support automated service chaining for custom user requests. The UAH Data Pool is based on a configurable technology framework that integrates distributed data services with a web interface and a set of centralized database services for catalogs and order tracking. While this instantiation of the Data Pool was implemented to meet the needs of the DISCOVER project, the framework was

Integrating robust timetabling in line plan optimization for railway systems

DEFF Research Database (Denmark)

Burggraeve, Sofie; Bull, Simon Henry; Lusby, Richard Martin

The line planning problem in rail is to select a number of lines froma potential pool which provides sufficient passenger capacity and meetsoperational requirements, with some objective measure of solution linequality. We model the problem of minimizing the average passenger systemtime, including...... frequency-dependent estimates for switching between lines,working with the Danish rail operator DSB and data for Copenhagen commuters.We present a multi-commodity flow formulation for the problemof freely routing passengers, coupled to discrete line-frequency decisionsselecting lines from a predefined pool...

Reflection of illumination laser from gas metal arc weld pool surface

International Nuclear Information System (INIS)

Ma, Xiaoji; Zhang, YuMing

2009-01-01

The weld pool is the core of the welding process where complex welding phenomena originate. Skilled welders acquire their process feedback primarily from the weld pool. Observation and measurement of the three-dimensional weld pool surface thus play a fundamental role in understanding and future control of complex welding processes. To this end, a laser line is projected onto the weld pool surface in pulsed gas metal arc welding (GMAW) and an imaging plane is used to intercept its reflection from the weld pool surface. Resultant images of the reflected laser are analyzed and it is found that the weld pool surface in GMAW does specularly reflect the projected laser as in gas tungsten arc welding (GTAW). Hence, the weld pool surface in GMAW is also specular and it is in principle possible that it may be observed and measured by projecting a laser pattern and then intercepting and imaging the reflection from it. Due to high frequencies of surface fluctuations, GMAW requires a relatively short time to image the reflected laser

Analysis of sodium pool fire in SFEF for assessing the limiting pool fire

International Nuclear Information System (INIS)

Mangarjuna Rao, P.; Ramesh, S.S.; Nashine, B.K.; Kasinathan, N.; Chellapandi, P.

2011-01-01

Accidental sodium leaks and resultant sodium fires in Liquid Metal Fast Breeder Reactor (LMFBR) systems can create a threat to the safe operation of the plant. To avoid this defence-in depth approach is implemented from the design stage of reactor itself. Rapid detection of sodium leak and fast dumping of the sodium into the storage tank of a defective circuit, leak collection trays, adequate lining of load bearing structural concrete and extinguishment of the sodium fire are the important defensive measures in the design, construction and operation of a LMFBR for protection against sodium leaks and their resultant fires. Evaluation of sodium leak events and their consequences by conducting large scale engineering experiments is very essential for effective implementation of the above protection measures for sodium fire safety. For this purpose a Sodium Fire Experimental Facility (SFEF) is constructed at SED, IGCAR. SFEF is having an experimental hall of size 9 m x 6 m x 10 m with 540 m 3 volume and its design pressure is 50 kPa. It is a concrete structure and provided with SS 304 liner, which is fixed to the inside surfaces of walls, ceiling and floor. A leak tight door of size (1.8 m x 2.0 m) is provided to the experimental hall and the facility is provided with a sodium equipment hall and a control room. Experimental evaluation of sodium pool fire consequences is an important activity in the LMFBR sodium fire safety related studies. An experimental program has been planned for different types of sodium fire studies in SFEF. A prior to that numerical analysis have been carried out for enclosed sodium pool fires using SOFIRE-II sodium pool fire code for SFEF experimental hall configuration to evaluate the limiting pool fire. This paper brings out results of the analysis carried out for this purpose. Limiting pool fire of SFEF depends on the exposed surface area of the pool, amount of sodium in the pool, oxygen concentration and initial sodium temperature. Limiting

Hawaii ESI: POOLS (Anchialine Pool Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for anchialine pools in Hawaii. Anchialine pools are small, relatively shallow coastal ponds that occur...

Cash pooling

OpenAIRE

Lozovaya, Karina

2009-01-01

This work makes a mention of cash management. At next chapter describes two most known theoretical models of cash management -- Baumol Model and Miller-Orr Model. Principal part of work is about cash pooling, types of cash pooling, cash pooling at Czech Republic and influence of cash pooling over accounting and taxes.

Electricity prices and generator behaviour in gross pool electricity markets

International Nuclear Information System (INIS)

O'Mahoney, Amy; Denny, Eleanor

2013-01-01

Electricity market liberalisation has become common practice internationally. The justification for this process has been to enhance competition in a market traditionally characterised by statutory monopolies in an attempt to reduce costs to end-users. This paper endeavours to see whether a pool market achieves this goal of increasing competition and reducing electricity prices. Here the electricity market is set up as a sealed bid second price auction. Theory predicts that such markets should result with firms bidding their marginal cost, thereby resulting in an efficient outcome and lower costs to consumers. The Irish electricity system with a gross pool market experiences among the highest electricity prices in Europe. Thus, we analyse the Irish pool system econometrically in order to test if the high electricity prices seen there are due to participants bidding outside of market rules or out of line with theory. Overall we do not find any evidence that the interaction between generator and the pool in the Irish electricity market is not efficient. Thus, the pool element of the market structure does not explain the high electricity prices experienced in Ireland. - Highlights: • We consider whether a gross pool achieves competitive behaviour. • We analyse the Irish pool system econometrically. • Results indicate the Irish pool system appears to work efficiently. • Generators appear to be bidding appropriately

Cells Lacking mtDNA Display Increased dNTP Pools upon DNA Damage

DEFF Research Database (Denmark)

Skovgaard, Tine; Rasmussen, Lene Juel; Munch-Petersen, Birgitte

Imbalanced dNTP pools are highly mutagenic due to a deleterious effect on DNA polymerase fidelity. Mitochondrial DNA defects, including mutations and deletions, are commonly found in a wide variety of different cancer types. In order to further study the interconnection between dNTP pools...... and mitochondrial function we have examined the effect of DNA damage on dNTP pools in cells deficient of mtDNA. We show that DNA damage induced by UV irradiation, in a dose corresponding to LD50, induces an S phase delay in different human osteosarcoma cell lines. The UV pulse also has a destabilizing effect...... shows that normal mitochondrial function is prerequisite for retaining stable dNTP pools upon DNA damage. Therefore it is likely that mitochondrial deficiency defects may cause an increase in DNA mutations by disrupting dNTP pool balance....

Solar swimming pool

Energy Technology Data Exchange (ETDEWEB)

1985-01-01

This report examines the feasibility of using solar collectors to heat the water in a previously unheated outdoor swimming pool. The solar system is used in conjunction with a pool blanket, to conserve heat when the pool is not in use. Energy losses through evaporation can be reduced by as much as 70% by a pool blanket. A total of 130 m{sup 2} of highly durable black synthetic collectors were installed on a support structure at a 30{degree} angle from the horizontal, oriented to the south. Circulation of pool water though the collectors, which is controlled by a differential thermostat, was done with the existing pool pump. Before installation the pool temperature averaged 16{degree}C; after installation it ranged from 20{degree} to 26{degree}C. It was hard to distinguish how much pool heating was due to the solar system and how much heat was retained by the pool blanket. However, the pool season was extended by five weeks and attendance tripled. 2 figs.

In Silico Pooling of ChIP-seq Control Experiments

Science.gov (United States)

Sun, Guannan; Srinivasan, Rajini; Lopez-Anido, Camila; Hung, Holly A.; Svaren, John; Keleş, Sündüz

2014-01-01

As next generation sequencing technologies are becoming more economical, large-scale ChIP-seq studies are enabling the investigation of the roles of transcription factor binding and epigenome on phenotypic variation. Studying such variation requires individual level ChIP-seq experiments. Standard designs for ChIP-seq experiments employ a paired control per ChIP-seq sample. Genomic coverage for control experiments is often sacrificed to increase the resources for ChIP samples. However, the quality of ChIP-enriched regions identifiable from a ChIP-seq experiment depends on the quality and the coverage of the control experiments. Insufficient coverage leads to loss of power in detecting enrichment. We investigate the effect of in silico pooling of control samples within multiple biological replicates, multiple treatment conditions, and multiple cell lines and tissues across multiple datasets with varying levels of genomic coverage. Our computational studies suggest guidelines for performing in silico pooling of control experiments. Using vast amounts of ENCODE data, we show that pairwise correlations between control samples originating from multiple biological replicates, treatments, and cell lines/tissues can be grouped into two classes representing whether or not in silico pooling leads to power gain in detecting enrichment between the ChIP and the control samples. Our findings have important implications for multiplexing samples. PMID:25380244

Designing ARVs Patent Pool Up to Trade & Policy Evolutionary Dynamics.

Science.gov (United States)

Dionisio, Daniele; Racalbuto, Vincenzo; Messeri, Daniela

2010-01-19

Patent pools for second and third-line Fixed Dose Combination (FDC) antiretroviral drugs (ARVs) should not be delayed as they are instrumental to urgent public health needs in the under-served markets.Nonetheless, multinational originator companies still seem to perceive patent pooling for ARVs as a minefield that would offer the generic competitors lots of deeply exploitable opportunities, to the detriment of patent owner's rights.This paper analyses the brand industry concerns, while looking for a strategy up to a really equitable and free world market, without any discrimination between end-users in wealthy and resource-limited countries.This strategy would urge partnerships between originator companies first to make newer FDC ARVs quickly available and allow patent pool agreements with generic counterparts to be negotiated straight afterwards.The patent pool strategy highlighted in this paper would assert the primacy of health over for-profit policies, while aligning with the 61(st) WHO's Assembly recommendations and G7, G8 and World Trade Organisation's warnings and pledges against trade protectionism.

Laser energy-pooling processes in an optically thick Cs vapor near a dissipative surface

International Nuclear Information System (INIS)

Gagne, Jean-Marie; Le Bris, Karine; Gagne, Marie-Claude

2002-01-01

We characterize, for the first time to our knowledge, the laser-induced backward fluorescence (retrofluorescence) spectra that result from energy-pooling collisions between Cs atoms near a dissipative thin Cs layer on a glass substrate. We resolve, experimentally and theoretically, the laser spectroscopic problem of energy-pooling processes related to the nature of the glass-metallic vapor interface. Our study focused on the integrated laser-induced retrofluorescence spectra for the 455.5-nm (7 2 P 3/2 -6 2 S 1/2 ) and 852.2-nm (6 2 P 3/2 -6 2 S 1/2 ) lines as a function of laser scanning through pumping resonance at the 852.2-nm line. We experimentally investigate the retrofluorescence from 420 to 930 nm, induced by a diode laser tuned either in the wings or in the center of the pumping resonance line. We present a detailed theoretical model of the retrofluorescence signal based on the radiative transfer equation, taking into account the evanescent wave of the excited atomic dipole strongly coupled with a dissipative surface. Based on theoretical and experimental results, we evaluate the effective nonradiative transfer rate A(bar sign) 6 2 P 3/2 →6 2 S 1/2s f for atoms in the excited 6 2 P 3/2 level located in the near-field region of the surface of the cell. Values extracted from the energy-pooling process analysis are equivalent to those found directly from the 852.2-nm resonance retrofluorescence line. We show that the effective energy-pooling coefficients k-tilde 7 2 P 3/2 and k-tilde 7 2 P 1/2 are approximately equal. The agreement between theory and experiment is remarkably good, considering the simplicity of the model

Impacts of initial convective structure on subsequent squall line evolution

Science.gov (United States)

Varble, A.; Morrison, H.; Zipser, E. J.

2017-12-01

A Weather Research and Forecasting simulation of the 20 May 2011 MC3E squall line using 750-m horizontal grid spacing produces wide convective regions with strongly upshear tilted convective updrafts and mesoscale bowing segments that are not produced in radar observations. Similar features occur across several different bulk microphysics schemes, despite surface observations exhibiting cold pool equivalent potential temperature drops that are similar to and pressure rises that are greater than those in the simulation. Observed rear inflow remains more elevated than simulated, partly counteracting the cold pool circulation, whereas the simulated rear inflow descends to low levels, maintaining its strength and reinforcing the cold pool circulation that overpowers the pre-squall line low level vertical wind shear. The descent and strength of the simulated rear inflow is fueled by strong latent cooling caused by large ice water contents detrained from upshear tilted convective cores that accumulate at the rear of the stratiform region. This simulated squall evolution is sensitive to model resolution, which is too coarse to resolve individual convective drafts. Nesting a 250-m horizontal grid spacing domain into the 750-m domain substantially alters the initial convective cells with reduced latent cooling, weaker convective downdrafts, and a weaker initial cold pool. As the initial convective cells develop into a squall line, the rear inflow remains more elevated in the 250-m domain with a cold pool that eventually develops to be just as strong and deeper than the one in the 750-m run. Despite this, the convective cores remain more upright in the 250-m run with the rear inflow partly counteracting the cold pool circulation, whereas the 750-m rear inflow near the surface reinforces the shallower cold pool and causes bowing in the squall line. The different structure in the 750-m run produces excessive mid-level front-to-rear detrainment that widens the convective region

Pool-Frenkel thermoelectric modulation of exciton photoluminescence in GaSe crystals

International Nuclear Information System (INIS)

Ertap, H.; Mamedov, G.M.; Karabulut, M.; Bacioglu, A.

2011-01-01

Effect of external field on the exciton photoluminescence of GaSe crystals has been investigated and it has been observed that the PL is quenched with the applied field. The changes observed in the PL spectra have been analyzed with impact exciton, Franz-Keldysh and Pool-Frenkel effects. From the analyses of the experimental data, it has been found that the intensity of direct free, indirect free and bound exciton peaks decreased exponentially with the square root of applied field as I∼exp-β√E. The energy positions of emission peaks were found to shift to longer wavelength with the applied field as ΔE∼β√E. From these findings, the Pool-Frenkel thermoelectric field effect is seen to be the dominant mechanism in the variation of exciton PL with the applied field even though the impact exciton and Franz-Keldysh effects contribute. - Highlights: → Exciton PL intensity varies with the applied field. It decreases with the square root of E in accordance with Pool-Frenkel effect. → In the intrinsic region of PL spectrum, lines belonging to direct and indirect free/bound excitons were observed. → Line positions shifted to longer wavelengths with the applied field. → It was shown that amplitude modulation of exciton PL with electric field was possible.

Genome-wide SNP scan of pooled DNA reveals nonsense mutation in FGF20 in the scaleless line of featherless chickens

Directory of Open Access Journals (Sweden)

Wells Kirsty L

2012-06-01

Full Text Available Abstract Background Scaleless (sc/sc chickens carry a single recessive mutation that causes a lack of almost all body feathers, as well as foot scales and spurs, due to a failure of skin patterning during embryogenesis. This spontaneous mutant line, first described in the 1950s, has been used extensively to explore the tissue interactions involved in ectodermal appendage formation in embryonic skin. Moreover, the trait is potentially useful in tropical agriculture due to the ability of featherless chickens to tolerate heat, which is at present a major constraint to efficient poultry meat production in hot climates. In the interests of enhancing our understanding of feather placode development, and to provide the poultry industry with a strategy to breed heat-tolerant meat-type chickens (broilers, we mapped and identified the sc mutation. Results Through a cost-effective and labour-efficient SNP array mapping approach using DNA from sc/sc and sc/+ blood sample pools, we map the sc trait to chromosome 4 and show that a nonsense mutation in FGF20 is completely associated with the sc/sc phenotype. This mutation, common to all sc/sc individuals and absent from wild type, is predicted to lead to loss of a highly conserved region of the FGF20 protein important for FGF signalling. In situ hybridisation and quantitative RT-PCR studies reveal that FGF20 is epidermally expressed during the early stages of feather placode patterning. In addition, we describe a dCAPS genotyping assay based on the mutation, developed to facilitate discrimination between wild type and sc alleles. Conclusions This work represents the first loss of function genetic evidence supporting a role for FGF ligand signalling in feather development, and suggests FGF20 as a novel central player in the development of vertebrate skin appendages, including hair follicles and exocrine glands. In addition, this is to our knowledge the first report describing the use of the chicken SNP array to

Southern Africa power pool : benefits, achievements, challenges and sustainability

International Nuclear Information System (INIS)

Anderson, G.O.; Opok, A.O.

2008-01-01

An overview of the Southern Africa Power Pool (SAPP) was presented. The SAPP was formed by 12 southern African developing countries as a means of minimizing electricity costs and maintaining reliability. The pool includes over 200 million people in a region of 9 million square meters. The SAPP relies on long-term bilateral contracts for electricity supply between customers and generators. The contracts are supplemented by short-term contracts in the short-term energy market. The pool uses a pricing mechanism with 13 detailed schedules dealing with firm power contracts of varying duration; non-firm power contracts of varying duration; mutual support contracts and emergency energy and control area services; scheduled outage energy; and energy banking. Benefits of the pool include reductions or postponements in generating capacity, reserves and fuel costs. New major initiatives planned by the SAPP include increasing interconnection points, the construction of new transmission lines, and the formulation of regional environmental studies. SAPP is now making plans to increase rural electrification in its membership countries with funding from an electricity levy. It was concluded that political and economic co-operation between member states has resulted in the sustained supply of energy in the region. 10 refs., 7 tabs., 3 figs

Exciting Pools

Science.gov (United States)

Wright, Bradford L.

1975-01-01

Advocates the creation of swimming pool oscillations as part of a general investigation of mechanical oscillations. Presents the equations, procedure for deriving the slosh modes, and methods of period estimation for exciting swimming pool oscillations. (GS)

A survey of endangered waterbirds on Maui and Oahu and assessment of potential impacts to waterbirds from the proposed Hawaii Geothermal Project transmission corridor. Final report

Energy Technology Data Exchange (ETDEWEB)

Evans, K.; Woodside, D.; Bruegmann, M. [Fish and Wildlife Service, Honolulu, HI (United States). Pacific Islands Office

1994-08-01

A survey of endangered waterbirds on Maui and Oahu was conducted during August and September 1993 to identify potential waterbird habitats within the general area of the proposed Hawaii Geothermal Project transmission corridor and to assess the potential impacts to endangered waterbird of installing and operating a high voltage transmission line from the Island of Hawaii to the islands of Oahu and Maui. Annual waterbird survey information and other literature containing information on specific wetland sites were summarized. Literature describing impacts of overhead transmission lines on birds was used to evaluate potential impacts of the proposed project on endangered waterbirds, resident wading birds, and migratory shorebirds and waterfowl. On Oahu, five wetland habitats supporting endangered Hawaiian waterbirds were identified within 2.5 miles of the proposed transmission line corridor. On Maui, three wetland habitats supporting endangered Hawaiian waterbirds were identified within the general area of the proposed transmission line corridor. Several of the wetlands identified on Oahu and Maui also supported resident wading birds and migratory shorebirds and waterfowl. Endangered waterbirds, resident wading birds, and migratory birds may collide with the proposed transmission lines wires. The frequency and numbers of bird collisions is expected to be greater on Oahu than on Maui because more wetland habitat exists and greater numbers of birds occur in the project area on Oahu. In addition, the endangered Hawaiian goose and the endangered Hawaiian petrel may be impacted by the proposed segment of the Hawaii Geothermal Project transmission line on Maui.

Study of mixed convection in sodium pool

International Nuclear Information System (INIS)

Wang Zhou; Chen Yan

1995-01-01

The mixed convection phenomena in the sodium pool of fast reactor have been studied systematically by the two dimensional modeling method. A generalized concept of circumferential line in the cylindrical coordinates was proposed to overcome the three dimensional effect induced by the pool geometry in an analysis of two dimensional modeling. A method of sub-step in time was developed for solving the turbulent equations. The treatments on the boundary condition for the auxiliary velocity field have been proposed, and the explanation of allowing the flow function method to be used in the flow field in presence of a mass source term was given. As examples of verification, the experiments were conducted with water flow in a rectangular cavity. The results from theoretical analysis were applied to the numerical computation for the mixed convection in the cavity. The mechanism of stratified flow in the cavity was studied. A numerical calculation was carried out for the mixed convection in hot plenum of a typical fast reactor

Seismic analysis and design of spent subassembly storage bay (SSSB) pool

International Nuclear Information System (INIS)

Abdul Gani, H.I.; Ramanjaneyulu, K.V.S.; Pillai, C.S.; Chetal, S.C.

2003-01-01

Fuel bundles, after their specified stay in reactor core, are replaced by fresh fuel for sustaining power generation at rated levels. The irradiated fuel subassembly, removed fresh from core, known as spent fuel sub assembly, is radioactive and decay heat generating. It needs to be cooled before it becomes amenable for handling, either for reprocessing or for immobilisation. For this purpose, it is immersed in a pool of water, retained in a concrete structure referred as Spent Subassembly Storage Bay (SSSB) pool. The height of water column above fuel bundles is arrived from shielding considerations. SSSB pool is one of the nuclear safety related structures and warrants rigorous analysis and design. The SSSB pool, in case of PFBR 500 MW(e) is located in fuel building. It is a stainless steel lined. water retaining rectangular R.C.C. open tank of size 7.5 X 29.0 m, with a height of 11.0 m. This structure is analysed for two levels of site specific earthquakes taking in to account liquid structure interactions as per ASCE-4, 1998. The design of walls and bottom slab is carried out satisfying the AERB code for nuclear safety related structures. Analysis and design of SSSB pool of PFBR is presented in the following paper. (author)

Swimming-pool piles

International Nuclear Information System (INIS)

Trioulaire, M.

1959-01-01

In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10 13 . This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [fr

Groundwater dependent pools in seasonal and permanent streams in the Clare Valley of South Australia

Directory of Open Access Journals (Sweden)

Erick Bestland

2017-02-01

In this Mediterranean climate with cool wet winters and dry hot summers strong salinity changes (up to 2.5 times due to seasonal cycles of wetting and drying were observed in surface water. Oxygen and hydrogen isotope values from pool sites showed strong evaporative enrichment during the dry season with up to 50% net evaporation calculated. Water isotopes from groundwater, however, cluster at the depleted end of the local meteoric water line and most do not show change despite significant seasonal salinity changes. Strontium isotope values and concentrations from the pools over the one year period do not define a mixing relationship. Instead, most pool sites have unchanging strontium isotope values despite the large seasonal change in salinity indicating strong evaporation of groundwater fed pools during this drought year.

An optimization based method for line planning to minimize travel time

DEFF Research Database (Denmark)

Bull, Simon Henry; Lusby, Richard Martin; Larsen, Jesper

2015-01-01

The line planning problem is to select a number of lines from a potential pool which provides sufficient passenger capacity and meets operational requirements, with some objective measure of solution line quality. We model the problem of minimizing the average passenger system time, including...

Spent fuel storage pool

International Nuclear Information System (INIS)

Murakami, Naoshi.

1996-01-01

Fences are disposed to a fuel exchange floor surrounding the upper surface of a fuel pool for preventing overflow of pool water. The fences comprise a plurality of flat boards arranged in parallel with each other in the longitudinal direction while being vertically inclined, and slits are disposed between the boards for looking down the pool. Further, the fences comprise wide boards and are constituted so as to be laid horizontally on the fuel exchange floor in a normal state and uprisen by means of the signals from an earthquake sensing device. Even if pool water is overflow from the fuel pool by the vibrations occurred upon earthquake and flown out to the floor of the fuel exchange floor, the overflow from the fuel exchange floor is prevented by the fences. An operator who monitors the fuel pool can observe the inside of the fuel pool through the slits formed to the fences during normal operation. The fences act as resistance against overflowing water upon occurrence of an earthquake thereby capable of reducing the overflowing amount of water due to the vibrations of pool water. The effect of preventing overflowing water can be enhanced. (N.H.)

Measurement of argon concentrations in a TRIGA Mark-III pool

Energy Technology Data Exchange (ETDEWEB)

Simms, R [California State University, Northridge, CA (United States)

1974-07-01

Argon-41, the principal radioactive effluent from a pool type reactor during normal operation, is produced by the {sup 40}A (n,{gamma}) reaction. The reactant, {sup 40}A, is introduced into the pool water by contact with the air. Reduction in radioactive argon release can be accomplished by reducing the concentration of dissolved {sup 40}A and retaining the {sup 41}A within the pool. However, little data were available concerning the mechanisms of argon introduction, production, retention, and release from a reactor pool. Experiments have therefore been performed at the Torrey Pines TRIGA Mark-III Reactor to develop techniques to sample dissolved argon and to provide data on argon concentrations in the pool for release modeling studies. Significant results for argon dissolved at different pool depths can only be obtained if the water samples are sealed at the point of collection. A special handling tool was developed to perform this remote operation. Pool samples were counted for {sup 41}A soon after collection with a NaI spectrometer. After allowing one day for decay of {sup 41}A, the concentration of {sup 40}A in the water sample was determined by neutron activation analysis. In each case, the 1.29 MeV gamma-ray peak of {sup 41}A was used. Interference from the 1.37 MeV {sup 24}Na peak was considered and its effect subtracted after determining {sup 24}Na content from the 2.75 MeV {sup 24}Na peak and a sodium standard. A Ge(Li) detector was tried and found to eliminate the problem, but it introduced an unacceptable geometrical effect dependent on bubble size within the sample bottles. Samples were taken from the 27 ft deep TRIGA pool at various locations. Results were obtained for samples taken on several different days along the same vertical line about 3-1/2 ft from the reactor centerline. Temperature measurements along this vertical traverse indicated a sharp temperature gradient at about 15 ft below the surface ({approx}6 ft above the top of the reactor). The

Snippets from the past: the evolution of Wade Hampton Frost's epidemiology as viewed from the American Journal of Hygiene/Epidemiology.

Science.gov (United States)

Morabia, Alfredo

2013-10-01

Wade Hampton Frost, who was a Professor of Epidemiology at Johns Hopkins University from 1919 to 1938, spurred the development of epidemiologic methods. His 6 publications in the American Journal of Hygiene, which later became the American Journal of Epidemiology, comprise a 1928 Cutter lecture on a theory of epidemics, a survey-based study of tonsillectomy and immunity to Corynebacterium diphtheriae (1931), 2 papers from a longitudinal study of the incidence of minor respiratory diseases (1933 and 1935), an attack rate ratio analysis of the decline of diphtheria in Baltimore (1936), and a 1936 lecture on the age, time, and cohort analysis of tuberculosis mortality. These 6 American Journal of Hygiene /American Journal of Epidemiology papers attest that Frost's personal evolution mirrored that of the emerging "early" epidemiology: The scope of epidemiology extended beyond the study of epidemics of acute infectious diseases, and rigorous comparative study designs and their associated quantitative methods came to light.

Evaluation of RSG-GAS purification system and pool warm water layer supplier performance

International Nuclear Information System (INIS)

Sudiyono; Suhadi; Diah-Erlina-Lestari

2005-01-01

Function of RSG-GAS purification system and warm water supplier (KBE 02) are to pick up dissolve activation result and another dirts of warm water layer. To keep quality of water at the decided level. The system is equipped by heater to supply warm water layer on the reactor pool surface the distribution is to reduce radiation level in the operation hall area a speciality on the reactor pool surface. Line KBE 02 tomord beam tube headitty system supplies water necessary to be shielding to beam tube in use off time. Of the RSG-GAS purification system and pool warm water layer performance date can be shown north of water is always in good condition. To require the dechded requirement. Resin live time is two years and then months

Operation and maintenance techniques of pool and pool water purification system in IMEF

Energy Technology Data Exchange (ETDEWEB)

Soong, Woong Sup

1999-03-01

IMEF pool is used pass way between pool and hot cell in order to inlet and outlet of fuel pin in cask. All operation is performed conforming with naked eyes. Therefore floating matter is filtered so as to easy under water handling. Also radioactivity in pool water is controlled according to the nuclear law, radioactivity ration maintained less than 15mR/hr on pool side. Perfect operation and maintenance can be achieved well trained operator. Result obtained from the perfection can give more influence over restrain, spreading contamination of radioactivity materials. This report describes operation and maintenance technique of pool water purification system in IMEF. (Author). 7 refs., 13 figs.

Operation and maintenance techniques of pool and pool water purification system in IMEF

International Nuclear Information System (INIS)

Soong, Woong Sup

1999-03-01

IMEF pool is used pass way between pool and hot cell in order to inlet and outlet of fuel pin in cask. All operation is performed conforming with naked eyes. Therefore floating matter is filtered so as to easy under water handling. Also radioactivity in pool water is controlled according to the nuclear law, radioactivity ration maintained less than 15mR/hr on pool side. Perfect operation and maintenance can be achieved well trained operator. Result obtained from the perfection can give more influence over restrain, spreading contamination of radioactivity materials. This report describes operation and maintenance technique of pool water purification system in IMEF. (Author). 7 refs., 13 figs

Swimming pool granuloma

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/001357.htm Swimming pool granuloma To use the sharing features on this page, please enable JavaScript. A swimming pool granuloma is a long-term (chronic) skin ...

Swimming pool hydraulics and their significance for public pools. Bedeutung der Beckenhydraulik in oeffentlichen Schwimmbaedern

Energy Technology Data Exchange (ETDEWEB)

Gansloser, G

1989-11-01

The term of swimming pool hydraulics means the process of letting in and drawing off water to and from the pool while ensuring that no inadmissible water-borne contaminant concentrations will occur anywhere within the pool. Measurements were performed on a pool to study the significance of correct pool hydraulics. The author points out that a wrong water recirculation design will bring to nought the effects of an elaborate water treatment system; by contrast, poor pool water quality can be greatly improved by redesigning the pool water hydraulics approach. In principle, systems with with water inlet at one side and water outlet at the far side will fall short of hygienic requirements. (BWI).

Unchanged thymidine triphosphate pools and thymidine metabolism in two lines of thymidine kinase 2-mutated fibroblasts.

Science.gov (United States)

Frangini, Miriam; Rampazzo, Chiara; Franzolin, Elisa; Lara, Mari-Carmen; Vilà, Maya R; Martí, Ramon; Bianchi, Vera

2009-02-01

Mitochondrial thymidine kinase (TK2) catalyzes the phosphorylation of thymidine in mitochondria. Its function becomes essential for dTTP synthesis in noncycling cells, where cytosolic dTTP synthesis via R1/R2 ribonucleotide reductase and thymidine kinase 1 is turned down. Mutations in the nuclear gene for TK2 cause a fatal mtDNA depletion syndrome. Only selected cell types are affected, suggesting that the other cells compensate for the TK2 deficiency by adapting the enzyme network that regulates dTTP synthesis outside S-phase. Here we looked for such metabolic adaptation in quiescent cultures of fibroblasts from two TK2-deficient patients with a slow-progressing syndrome. In cell extracts, we measured the activities of TK2, deoxycytidine kinase, thymidine phosphorylase, deoxynucleotidases and the amounts of the three ribonucleotide reductase subunits. Patient cells contained 40% or 5% TK2 activity and unchanged activities of the other enzymes. However, their mitochondrial and cytosolic dTTP pools were unchanged, and also the overall composition of the dNTP pools was normal. TK2-dependent phosphorylation of [(3)H]thymidine in intact cells and the turnover of the dTTP pool showed that even the fibroblasts with 5% residual TK2 activity synthesized dTTP at an almost normal rate. Normal fibroblasts apparently contain more TK2 than needed to maintain dTTP during quiescence, which would explain why TK2-mutated fibroblasts do not manifest mtDNA depletion despite their reduced TK2 activity.

PDA: Pooled DNA analyzer

Directory of Open Access Journals (Sweden)

Lin Chin-Yu

2006-04-01

Full Text Available Abstract Background Association mapping using abundant single nucleotide polymorphisms is a powerful tool for identifying disease susceptibility genes for complex traits and exploring possible genetic diversity. Genotyping large numbers of SNPs individually is performed routinely but is cost prohibitive for large-scale genetic studies. DNA pooling is a reliable and cost-saving alternative genotyping method. However, no software has been developed for complete pooled-DNA analyses, including data standardization, allele frequency estimation, and single/multipoint DNA pooling association tests. This motivated the development of the software, 'PDA' (Pooled DNA Analyzer, to analyze pooled DNA data. Results We develop the software, PDA, for the analysis of pooled-DNA data. PDA is originally implemented with the MATLAB® language, but it can also be executed on a Windows system without installing the MATLAB®. PDA provides estimates of the coefficient of preferential amplification and allele frequency. PDA considers an extended single-point association test, which can compare allele frequencies between two DNA pools constructed under different experimental conditions. Moreover, PDA also provides novel chromosome-wide multipoint association tests based on p-value combinations and a sliding-window concept. This new multipoint testing procedure overcomes a computational bottleneck of conventional haplotype-oriented multipoint methods in DNA pooling analyses and can handle data sets having a large pool size and/or large numbers of polymorphic markers. All of the PDA functions are illustrated in the four bona fide examples. Conclusion PDA is simple to operate and does not require that users have a strong statistical background. The software is available at http://www.ibms.sinica.edu.tw/%7Ecsjfann/first%20flow/pda.htm.

13 CFR 120.1706 - Pool Originator's retained interest in Pool.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Pool Originator's retained interest in Pool. 120.1706 Section 120.1706 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan...

Bioreactor scale up and protein product quality characterization of piggyBac transposon derived CHO pools.

Science.gov (United States)

Rajendra, Yashas; Balasubramanian, Sowmya; Peery, Robert B; Swartling, James R; McCracken, Neil A; Norris, Dawn L; Frye, Christopher C; Barnard, Gavin C

2017-03-01

Chinese hamster ovary (CHO) cells remain the most popular host for the production of biopharmaceutical drugs, particularly monoclonal antibodies (mAbs), bispecific antibodies, and Fc-fusion proteins. Creating and characterizing the stable CHO clonally-derived cell lines (CDCLs) needed to manufacture these therapeutic proteins is a lengthy and laborious process. Therefore, CHO pools have increasingly been used to rapidly produce protein to support and enable preclinical drug development. We recently described the generation of CHO pools yielding mAb titers as high as 7.6 g/L in a 16 day bioprocess using piggyBac transposon-mediated gene integration. In this study, we wanted to understand why the piggyBac pool titers were significantly higher (2-10 fold) than the control CHO pools. Higher titers were the result of a combination of increased average gene copy number, significantly higher messenger RNA levels and the homogeneity (i.e. less diverse population distribution) of the piggyBac pools, relative to the control pools. In order to validate the use of piggyBac pools to support preclinical drug development, we then performed an in-depth product quality analysis of purified protein. The product quality of protein obtained from the piggyBac pools was very similar to the product quality profile of protein obtained from the control pools. Finally, we demonstrated the scalability of these pools from shake flasks to 36L bioreactors. Overall, these results suggest that gram quantities of therapeutic protein can be rapidly obtained from piggyBac CHO pools without significantly changing product quality attributes. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:534-540, 2017. © 2017 American Institute of Chemical Engineers.

Diversity in host clone performance within a Chinese hamster ovary cell line.

Science.gov (United States)

O'Callaghan, Peter M; Berthelot, Maud E; Young, Robert J; Graham, James W A; Racher, Andrew J; Aldana, Dulce

2015-01-01

Much effort has been expended to improve the capabilities of individual Chinese hamster ovary (CHO) host cell lines to synthesize recombinant therapeutic proteins (rPs). However, given the increasing variety in rP molecular types and formats it may be advantageous to employ a toolbox of CHO host cell lines in biomanufacturing. Such a toolbox would contain a panel of hosts with specific capabilities to synthesize certain molecular types at high volumetric concentrations and with the correct product quality (PQ). In this work, we examine a panel of clonally derived host cell lines isolated from CHOK1SV for the ability to manufacture two model proteins, an IgG4 monoclonal antibody (Mab) and an Fc-fusion protein (etanercept). We show that these host cell lines vary in their relative ability to synthesize these proteins in transient and stable pool production format. Furthermore, we examined the PQ attributes of the stable pool-produced Mab and etanercept (by N-glycan ultra performance liquid chromatography (UPLC) and liquid chromatography - tandem mass spectrometry (LC-MS/MS), respectively), and uncovered substantial variation between the host cell lines in Mab N-glycan micro-heterogeneity and etanercept N and O-linked macro-heterogeneity. To further investigate the capabilities of these hosts to act as cell factories, we examined the glycosylation pathway gene expression profiles as well as the levels of endoplasmic reticulum (ER) and mitochondria in the untransfected hosts. We uncovered a moderate correlation between ER mass and the volumetric product concentration in transient and stable pool Mab production. This work demonstrates the utility of leveraging diversity within the CHOK1SV pool to identify new host cell lines with different performance characteristics. © 2015 American Institute of Chemical Engineers.

Efficient evaluation of humoral immune responses by the use of serum pools

DEFF Research Database (Denmark)

Sternbæk, Louise; Draborg, Anette H.; Nielsen, Christoffer T.

2017-01-01

has considered using serum pools as a quick and efficient screening method to confirm or deny hypotheses. Methods We created serum pools from four different patient groups (systemic lupus erythematosus n = 85, rheumatoid arthritis n = 77, Sjögren's syndrome n = 91, systemic sclerosis n = 66) and one......Background Collection and testing of individual serum samples are often used in research to gain knowledge about e.g. the humoral response against bacteria or virus. This is a valid but time-consuming method and might be a waste of valuable serum samples for inefficient research. So far, no study...... healthy control group (n = 67). Each serum pool was analyzed using three well-known immunoassays: enzyme-linked immunosorbent assay (ELISA), line blot, and immunofluorescence microscopy (anti-nuclear antibody (ANA) screening). The presence of Epstein-Barr virus (EBV) EA/D-, EBNA-1-, VCA p23-, and gp350...

Benthic assemblages of rock pools in northern Portugal: seasonal and between-pool variability

Directory of Open Access Journals (Sweden)

Iacopo Bertocci

2012-11-01

Full Text Available We investigated the seasonal (winter vs summer and within season and spatial (between-pool variability of benthic assemblages of rock pools at mid-intertidal level along the shore of Viana do Castelo (North Portugal. Physical traits of rock pools, including size, depth and position along the shore, were also compared between pools. While pools did not differ for any of the examined physical traits, results indicated a clear seasonal difference in the structure of assemblages, including a total of 49 macroalgal and 13 animal taxa. This finding was driven by six taxa that are more abundant in winter (the reef-forming polychaete Sabellaria alveolata, the articulated coralline algae Corallina spp., the brown alga Bifurcaria bifurcata, the encrusting coralline alga Lithophyllum incrustans, the red alga Chondracanthus acicularis and the grazing snails Gibbula spp. and four algal taxa that are more abundant in summer (the invasive brown Sargassum muticum, the green Ulva spp., the kelp Laminaria ochroleuca and the filamentous red Ceramium spp.. These data provide a new contribution to the knowledge of rock pool systems and have potential implications for monitoring programmes aimed at assessing ecological modifications related to natural and anthropogenic disturbances and for identifying processes responsible for the variability of rock pool assemblages.

Towards predicting wading bird densities from predicted prey densities in a post-barrage Severn estuary

International Nuclear Information System (INIS)

Goss-Custard, J.D.; McGrorty, S.; Clarke, R.T.; Pearson, B.; Rispin, W.E.; Durell, S.E.A. le V. dit; Rose, R.J.; Warwick, R.M.; Kirby, R.

1991-01-01

A winter survey of seven species of wading birds in six estuaries in south-west England was made to develop a method for predicting bird densities should a tidal power barrage be built on the Severn estuary. Within most estuaries, bird densities correlated with the densities of widely taken prey species. A barrage would substantially reduce the area of intertidal flats available at low water for the birds to feed but the invertebrate density could increase in the generally more benign post-barrage environmental conditions. Wader densities would have to increase approximately twofold to allow the same overall numbers of birds to remain post-barrage as occur on the Severn at present. Provisional estimates are given of the increases in prey density required to allow bird densities to increase by this amount. With the exception of the prey of dunlin, these fall well within the ranges of densities found in other estuaries, and so could in principle be attained in the post-barrage Severn. An attempt was made to derive equations with which to predict post-barrage densities of invertebrates from easily measured, static environmental variables. The fact that a site was in the Severn had a significant additional effect on invertebrate density in seven cases. This suggests that there is a special feature of the Severn, probably one associated with its highly dynamic nature. This factor must be identified if the post-barrage densities of invertebrates are to be successful predicted. (author)

Big city consultants shut down our pool : a shocking community pool gets checked for stray voltage

Energy Technology Data Exchange (ETDEWEB)

Lynch, P. [Power Line Systems Engineering Inc., Markham, ON (Canada)

2009-12-15

This article discussed an investigation conducted at a community pool where swimmers complained of receiving electrical shocks both in the pool and on the pool's deck area. Electrical measurements taken at the pool revealed current flows from the pool water to various points around the deck area. Measured current flow in the pool area was 30 amps even when the main pool service breaker was opened to shut off power to the entire facility. Thirty amps of primary neutral current was then measured on the primary side aerial neutral in front of the pool. A 10 amp primary feeder from the pool joined up with the complex's primary neutral wire to increase the neutral current to 40 amps. The combined 40 amps current then returned to the secondary side of a nearby utility transformer substation. The study showed that the underground wet low-resistance grounded surface area of the pool was attracting the 30 amps of utility current from the surrounding ground area. The local utility disconnected the primary and secondary neutral interconnection at the pool's main 600-volt step-down transformer. The pool deck was removed in order to install additional copper bonding grounds. In order to avert serious injuries, many experts propose that all electric utilities should be required by law to reconfigure their power systems to prevent primary power neutral currents from entering private buildings. 1 tab., 2 figs.

poolHiTS: A Shifted Transversal Design based pooling strategy for high-throughput drug screening

Directory of Open Access Journals (Sweden)

Woolf Peter J

2008-05-01

Full Text Available Abstract Background A key goal of drug discovery is to increase the throughput of small molecule screens without sacrificing screening accuracy. High-throughput screening (HTS in drug discovery involves testing a large number of compounds in a biological assay to identify active compounds. Normally, molecules from a large compound library are tested individually to identify the activity of each molecule. Usually a small number of compounds are found to be active, however the presence of false positive and negative testing errors suggests that this one-drug one-assay screening strategy can be significantly improved. Pooling designs are testing schemes that test mixtures of compounds in each assay, thereby generating a screen of the whole compound library in fewer tests. By repeatedly testing compounds in different combinations, pooling designs also allow for error-correction. These pooled designs, for specific experiment parameters, can be simply and efficiently created using the Shifted Transversal Design (STD pooling algorithm. However, drug screening contains a number of key constraints that require specific modifications if this pooling approach is to be useful for practical screen designs. Results In this paper, we introduce a pooling strategy called poolHiTS (Pooled High-Throughput Screening which is based on the STD algorithm. In poolHiTS, we implement a limit on the number of compounds that can be mixed in a single assay. In addition, we show that the STD-based pooling strategy is limited in the error-correction that it can achieve. Due to the mixing constraint, we show that it is more efficient to split a large library into smaller blocks of compounds, which are then tested using an optimized strategy repeated for each block. We package the optimal block selection algorithm into poolHiTS. The MATLAB codes for the poolHiTS algorithm and the corresponding decoding strategy are also provided. Conclusion We have produced a practical version

Gene pool conservation and tree improvement in Serbia

Directory of Open Access Journals (Sweden)

Isajev Vasilije

2009-01-01

Full Text Available This paper presents the concepts applied in the gene pool conservation and tree improvement in Serbia. Gene pool conservation of tree species in Serbia includes a series of activities aiming at the sustainability and protection of genetic and species variability. This implies the investigation of genetic resources and their identification through the research of the genetic structure and the breeding system of individual species. Paper also includes the study of intra- and inter-population variability in experiments - provenance tests, progeny tests, half- and full-sib lines, etc. The increased use of the genetic potential in tree improvement in Serbia should be intensified by the following activities: improvement of production of normal forest seed, application of the concept of new selections directed primarily to the improvement of only one character, because in that case the result would be certain, establishment and management of seed orchards as specialized plantations for long-term production of genetically good-quality forest seeds, and the shortening of the improvement process by introducing new techniques and methods (molecular markers, somaclonal variation, genetic engineering, protoplast fusion, micropropagation, etc..

Pool scrubbing

International Nuclear Information System (INIS)

Lopez-Jimenez, J.; Herranz, J.; Escudero, M.J.; Espigares, M.M.; Peyres, V.; Polo, J.; Kortz, Ch.; Koch, M.K.; Brockmeier, U.; Unger, H.; Dutton, L.M.C.; Smedley, Ch.; Trow, W.; Jones, A.V.; Bonanni, E.; Calvo, M.; Alonso, A.

1996-12-01

The Source Term Project in the Third Frame Work Programme of the European Union Was conducted under and important joined effort on pool scrubbing research. CIEMAT was the Task Manager of the project and several other organizations participated in it: JRC-Ispra, NNC Limited, RUB-NES and UPM. The project was divided into several tasks. A peer review of the models in the pool scrubbing codes SPARC90 and BUSCA-AUG92 was made, considering the different aspects in the hydrodynamic phenomenology, particle retention and fission product vapor abortions. Several dominant risk accident sequences were analyzed with MAAP, SPARC90 and BUSCA-AUG92 codes, and the predictions were compared. A churn-turbulent model was developed for the hydrodynamic behaviour of the pool. Finally, an experimental programme in the PECA facility of CIEMAT was conducted in order to study the decontamination factor under jet injection regime, and the experimental observations were compared with the SPARC and BUSCA codes. (Author)

A pooled analysis of sequential therapies with sorafenib and sunitinib in metastatic renal cell carcinoma.

Science.gov (United States)

Stenner, Frank; Chastonay, Rahel; Liewen, Heike; Haile, Sarah R; Cathomas, Richard; Rothermundt, Christian; Siciliano, Raffaele D; Stoll, Susanna; Knuth, Alexander; Buchler, Tomas; Porta, Camillo; Renner, Christoph; Samaras, Panagiotis

2012-01-01

To evaluate the optimal sequence for the receptor tyrosine kinase inhibitors (rTKIs) sorafenib and sunitinib in metastatic renal cell cancer. We performed a retrospective analysis of patients who had received sequential therapy with both rTKIs and integrated these results into a pooled analysis of available data from other publications. Differences in median progression-free survival (PFS) for first- (PFS1) and second-line treatment (PFS2), and for the combined PFS (PFS1 plus PFS2) were examined using weighted linear regression. In the pooled analysis encompassing 853 patients, the median combined PFS for first-line sunitinib and 2nd-line sorafenib (SuSo) was 12.1 months compared with 15.4 months for the reverse sequence (SoSu; 95% CI for difference 1.45-5.12, p = 0.0013). Regarding first-line treatment, no significant difference in PFS1 was noted regardless of which drug was initially used (0.62 months average increase on sorafenib, 95% CI for difference -1.01 to 2.26, p = 0.43). In second-line treatment, sunitinib showed a significantly longer PFS2 than sorafenib (average increase 2.66 months, 95% CI 1.02-4.3, p = 0.003). The SoSu sequence translates into a longer combined PFS compared to the SuSo sequence. Predominantly the superiority of sunitinib regarding PFS2 contributed to the longer combined PFS in sequential use. Copyright © 2012 S. Karger AG, Basel.

An applied optimization based method for line planning to minimize travel time

DEFF Research Database (Denmark)

Bull, Simon Henry; Rezanova, Natalia Jurjevna; Lusby, Richard Martin

The line planning problem in rail is to select a number of lines froma potential pool which provides sufficient passenger capacity and meetsoperational requirements, with some objective measure of solution linequality. We model the problem of minimizing the average passenger systemtime, including...

Wading bird guano contributes to Hg accumulation in tree island soils in the Florida Everglades

International Nuclear Information System (INIS)

Zhu, Yingjia; Gu, Binhe; Irick, Daniel L.; Ewe, Sharon; Li, Yuncong; Ross, Michael S.; Ma, Lena Q.

2014-01-01

Tree islands are habitat for wading birds and a characteristic landscape feature in the Everglades. A total of 93 surface soil and 3 soil core samples were collected from 7 degraded/ghost and 34 live tree islands. The mean Hg concentration in surface soils of ghost tree islands was low and similar to marsh soil. For live tree islands, Hg concentrations in the surface head region were considerably greater than those in mid and tail region, and marsh soils. Hg concentrations in bird guano (286 μg kg −1 ) were significantly higher than those in mammal droppings (105 μg kg −1 ) and plant leaves (53 μg kg −1 ). In addition, Hg concentrations and δ 15 N values displayed positive correlation in soils influenced by guano. During 1998–2010, estimated annual Hg deposition by guano was 148 μg m −2 yr −1 and ∼8 times the atmospheric deposition. Highlights: • Hg concentrations in the head region of tree islands were the highest. • Hg concentrations in bird guano (286 μg kg −1 ) were significantly higher than those in mammal droppings and plant leaves. • Hg concentrations and δ 15 N values showed positive correlation in soils influenced by guano. • Estimated annual Hg deposition by guano was 148 μg m −2 yr −1 , ∼8 times the atmospheric deposition. -- The annual Hg deposition by bird guano to tree island soils in the Everglades was ∼8 times the atmospheric deposition

Design of hydrotherapy exercise pools.

Science.gov (United States)

Edlich, R F; Abidin, M R; Becker, D G; Pavlovich, L J; Dang, M T

1988-01-01

Several hydrotherapy pools have been designed specifically for a variety of aquatic exercise. Aqua-Ark positions the exerciser in the center of the pool for deep-water exercise. Aqua-Trex is a shallow underwater treadmill system for water walking or jogging. Swim-Ex generates an adjustable laminar flow that permits swimming without turning. Musculoskeletal conditioning can be accomplished in the above-ground Arjo shallow-water exercise pool. A hydrotherapy pool also can be custom designed for musculoskeletal conditioning in its shallow part and cardiovascular conditioning in a deeper portion of the pool. Regardless of the type of exercise, there is general agreement that the specific exercise conducted in water requires significantly more energy expenditure than when the same exercise is performed on land.

Simulation of the Gamma Dose Rate in Loss of Pool Water Accident of the Second Egyptian Research Reactor ETRR-2

International Nuclear Information System (INIS)

Amin, E.; Saleh, H.; Ashoub, N.

2000-01-01

The Second Egyptian Research Reactor ETRR-2, is a pool type reactor, a sudden loss of pool water resulting of leaving the core region un-covered. The reactor core is surrounded by chimney chambers whose water is isolated from pool water. This accident would lead to significant external dose. A model is developed and is used to calculate the dose rates for key access and traffic plans from indirect line of sight of the core have a maximum dose rate. The model developed uses the discrete ordinate method as implemented in the code DOT 3.5

Swimming pool cleaner poisoning

Science.gov (United States)

Swimming pool cleaner poisoning occurs when someone swallows this type of cleaner, touches it, or breathes in ... The harmful substances in swimming pool cleaner are: Bromine ... copper Chlorine Soda ash Sodium bicarbonate Various mild acids

Proximity to overhead power lines and childhood leukaemia

DEFF Research Database (Denmark)

Amoon, Aryana T; Crespi, Catherine M; Ahlbom, Anders

2018-01-01

BACKGROUND: Although studies have consistently found an association between childhood leukaemia risk and magnetic fields, the associations between childhood leukaemia and distance to overhead power lines have been inconsistent. We pooled data from multiple studies to assess the association with d...

Efficient pooling designs for library screening

OpenAIRE

Bruno, William J.; Knill, Emanuel; Balding, David J.; Bruce, D. C.; Doggett, N. A.; Sawhill, W. W.; Stallings, R. L.; Whittaker, Craig C.; Torney, David C.

1994-01-01

We describe efficient methods for screening clone libraries, based on pooling schemes which we call ``random $k$-sets designs''. In these designs, the pools in which any clone occurs are equally likely to be any possible selection of $k$ from the $v$ pools. The values of $k$ and $v$ can be chosen to optimize desirable properties. Random $k$-sets designs have substantial advantages over alternative pooling schemes: they are efficient, flexible, easy to specify, require fewer pools, and have er...

21 CFR 1250.89 - Swimming pools.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Swimming pools. 1250.89 Section 1250.89 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.89 Swimming pools. (a) Fill and draw swimming pools shall not be installed or used. (b) Swimming pools of the recirculation type shall be...

Assessment of left ventricular function by gated myocardial perfusion and gated blood-pool SPECT. Can we use the same reference database?

Energy Technology Data Exchange (ETDEWEB)

Paul, A.K.; Hasegawa, Shinji; Yoshioka, Jun; Yamaguchi, Hitoshi; Tsujimura, Eiichiro; Nishimura, Tsunehiko [Osaka Univ., Suita (Japan). Graduate School of Medicine

2000-04-01

The purpose of this study was to compare left ventricular (LV) volume and ejection fraction (LVEF) measurements obtained with electrocardiographic gated single-photon emission computed tomographic (SPECT) myocardial perfusion imaging (GS-MPI) with those obtained with gated SPECT cardiac blood-pool imaging (GS-pool). Fifteen patients underwent GS-MPI with technetium-99m tetrofosmin and GS-pool with technetium-99m-erythrocyte, within a mean interval of 8{+-}3 days. Eight patients had suspected dilated cardiomyopathy and seven patients had angiographically significant coronary artery disease. End-diastolic volume (EDV), end-systolic volume (ESV) and LVEF measurements were estimated from GS-MPI images by means of Cedars-Sinai automatic quantitative program and from GS-pool images by the threshold technique. Mean differences between GS-MPI and GS-pool in EDV, ESV and LVEF measurements were -2.8{+-}10.5 ml [95% confidence interval (CI): -8.6{+-}3.0 ml], 2.6{+-}7.3 ml (CI: -1.4-6.6 ml) and -2.3{+-}5.1% (CI: -5.1-0.6%), respectively. No significant difference in the mean differences from 0 was found for EDV, ESV or LVEF measurements. Bland-Altman plots revealed no trend over the measured LV volumes and LVEF. For all parameters, regression lines approximated lines of identity. The excellent agreement between GS-MPI and GS-pool measurements suggests that, for estimation of LV volumes and LVEF, these two techniques may be used interchangeably and measurements by one method can serve as a reference for the other. (author)

Modal analysis of pool door in water tank

Energy Technology Data Exchange (ETDEWEB)

Kim, Kang Soo; Jeong, Kyeong Hoon; Park, Chan Gook; Koo, In Soo [KAERI, Daejeon (Korea, Republic of)

2012-10-15

A pool door is installed at the chase of the pool gate by means of an overhead crane in the building of a research reactor. The principal function of the pool door, which is located between the reactor pool and service pool, is to separate the reactor pool from the service pool for the maintenance and/or the removal of the equipment either in the reactor pool or service pool. The pool door consists of stainless steel plates supported by structural steel frames and sealing components. The pool door is equipped with double inflatable gaskets. The configuration of the pool door is shown in Figure 1. The FEM analysis and theoretical calculation by the formula were performed to evaluate the natural frequency for the pool door in the water. The results from the two methods were compared.

Numerical modeling of sodium fire – Part II: Pool combustion and combined spray and pool combustion

International Nuclear Information System (INIS)

Sathiah, Pratap; Roelofs, Ferry

2014-01-01

Highlights: • A CFD based method is proposed for the simulation of sodium pool combustion. • A sodium evaporation based model is proposed to model sodium pool evaporation. • The proposed method is validated against sodium pool experiments of Newman and Payne. • The results obtained using the proposed method are in good agreement with the experiments. - Abstract: The risk of sodium-air reaction has received considerable attention after the sodium-fire accident in Monju reactor. The fires resulting from the sodium-air reaction can be detrimental to the safety of a sodium fast reactor. Therefore, predicting the consequences of a sodium fire is important from a safety point of view. A computational method based on CFD is proposed here to simulate sodium pool fire and understand its characteristics. The method solves the Favre-averaged Navier-Stokes equation and uses a non-premixed mixture fraction based combustion model. The mass transfer of sodium vapor from the pool surface to the flame is obtained using a sodium evaporation model. The proposed method is then validated against well-known sodium pool experiments of Newman and Payne. The flame temperature and location predicted by the model are in good agreement with experiments. Furthermore, the trends of the mean burning rate with initial pool temperature and oxygen concentration are captured well. Additionally, parametric studies have been performed to understand the effects of pool diameter and initial air temperature on the mean burning rate. Furthermore, the sodium spray and sodium pool combustion models are combined to simulate simultaneous spray and pool combustion. Simulations were performed to demonstrate that the combined code could be applied to simulate this. Once sufficiently validated, the present code can be used for safety evaluation of a sodium fast reactor

Numerical modeling of sodium fire – Part II: Pool combustion and combined spray and pool combustion

Energy Technology Data Exchange (ETDEWEB)

Sathiah, Pratap, E-mail: pratap.sathiah78@gmail.com [Shell Global Solutions Ltd., Brabazon House, Concord Business Park, Threapwood Road, Manchester M220RR (United Kingdom); Roelofs, Ferry, E-mail: roelofs@nrg.eu [Nuclear Research and Consultancy Group (NRG), Westerduinweg 3, 1755ZG Petten (Netherlands)

2014-10-15

Highlights: • A CFD based method is proposed for the simulation of sodium pool combustion. • A sodium evaporation based model is proposed to model sodium pool evaporation. • The proposed method is validated against sodium pool experiments of Newman and Payne. • The results obtained using the proposed method are in good agreement with the experiments. - Abstract: The risk of sodium-air reaction has received considerable attention after the sodium-fire accident in Monju reactor. The fires resulting from the sodium-air reaction can be detrimental to the safety of a sodium fast reactor. Therefore, predicting the consequences of a sodium fire is important from a safety point of view. A computational method based on CFD is proposed here to simulate sodium pool fire and understand its characteristics. The method solves the Favre-averaged Navier-Stokes equation and uses a non-premixed mixture fraction based combustion model. The mass transfer of sodium vapor from the pool surface to the flame is obtained using a sodium evaporation model. The proposed method is then validated against well-known sodium pool experiments of Newman and Payne. The flame temperature and location predicted by the model are in good agreement with experiments. Furthermore, the trends of the mean burning rate with initial pool temperature and oxygen concentration are captured well. Additionally, parametric studies have been performed to understand the effects of pool diameter and initial air temperature on the mean burning rate. Furthermore, the sodium spray and sodium pool combustion models are combined to simulate simultaneous spray and pool combustion. Simulations were performed to demonstrate that the combined code could be applied to simulate this. Once sufficiently validated, the present code can be used for safety evaluation of a sodium fast reactor.

10 CFR 36.63 - Pool water purity.

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Pool water purity. 36.63 Section 36.63 Energy NUCLEAR... § 36.63 Pool water purity. (a) Pool water purification system must be run sufficiently to maintain the conductivity of the pool water below 20 microsiemens per centimeter under normal circumstances. If pool water...

Replacement of thermal column elastomeric gasket in pool type research reactors based on ageing and radiation degradation

International Nuclear Information System (INIS)

Garai, S.K.

2006-01-01

Pool type research reactors are designed with Thermal column facilities to irradiate samples at different flux levels of thermal neutrons. The sealing of demineralised pool water between stainless steel lined pool wall and the Aluminium Thermal column plate is achieved by an elastomeric gasket. The gasket joint is subjected to pool water temperature ranging from 25degC to 45degC and radiation field of the order of 104 -106 R/hr. The gasket loses its sealing properties due to ageing and radiation degradation after a few years, leading to the leakage and loss of the pool water. Though degradation of the gasket is, generally, predictable, some amount of uncertainty always remains in the leakage rate. The paper describes the study of a few elastomers in radiation environment and replacement of the Thermal column gasket of a swimming pool type research reactor. It includes the details of features like planning and scheduling, the actual sequential execution of the job, various problems encountered and corrective measures applied, engineering and radiological safety measures adopted, development of remote tools, disassembly and reassembly procedure and finally satisfactory completion of the site job in high radiation environment with minimum time and man rem consumption. (author)

Model of large pool fires

Energy Technology Data Exchange (ETDEWEB)

Fay, J.A. [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)]. E-mail: jfay@mit.edu

2006-08-21

A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables.

Model of large pool fires

International Nuclear Information System (INIS)

Fay, J.A.

2006-01-01

A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables

POOL WATER TREATMENT AND COOLING SYSTEM DESCRIPTION DOCUMENT

International Nuclear Information System (INIS)

King, V.

2000-01-01

The Pool Water Treatment and Cooling System is located in the Waste Handling Building (WHB), and is comprised of various process subsystems designed to support waste handling operations. This system maintains the pool water temperature within an acceptable range, maintains water quality standards that support remote underwater operations and prevent corrosion, detects leakage from the pool liner, provides the capability to remove debris from the pool, controls the pool water level, and helps limit radiological exposure to personnel. The pool structure and liner, pool lighting, and the fuel staging racks in the pool are not within the scope of the Pool Water Treatment and Cooling System. Pool water temperature control is accomplished by circulating the pool water through heat exchangers. Adequate circulation and mixing of the pool water is provided to prevent localized thermal hotspots in the pool. Treatment of the pool water is accomplished by a water treatment system that circulates the pool water through filters, and ion exchange units. These water treatment units remove radioactive and non-radioactive particulate and dissolved solids from the water, thereby providing the water clarity needed to conduct waste handling operations. The system also controls pool water chemistry to prevent advanced corrosion of the pool liner, pool components, and fuel assemblies. Removal of radioactivity from the pool water contributes to the project ALARA (as low as is reasonably achievable) goals. A leak detection system is provided to detect and alarm leaks through the pool liner. The pool level control system monitors the water level to ensure that the minimum water level required for adequate radiological shielding is maintained. Through interface with a demineralized water system, adequate makeup is provided to compensate for loss of water inventory through evaporation and waste handling operations. Interface with the Site Radiological Monitoring System provides continuous

Pool scrubbing models for iodine components

Energy Technology Data Exchange (ETDEWEB)

Fischer, K [Battelle Ingenieurtechnik GmbH, Eschborn (Germany)

1996-12-01

Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs.

Pool scrubbing models for iodine components

International Nuclear Information System (INIS)

Fischer, K.

1996-01-01

Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs

Simulation of the gamma dose rate in a loss of pool water accident of the second Egyptian research reactor ET-RR-2

International Nuclear Information System (INIS)

Amin, E.; Saleh, H.G.; Ashoub, N.

2002-01-01

The second Egyptian research reactor ET-RR-2, is a pool type reactor. A sudden loss of pool water would leave the core region uncovered. The reactor core is surrounded by chimney chambers with water isolated from the pool water. This accident would lead to significant external doses. A model is developed and used to calculate the dose rates for key access-areas and traffic plans from indirect line of sight of the core which have a maximum dose rate. The model developed uses the discrete ordinate method as implemented in the code DOT3.5. (orig.) [de

The economics of power generation in Alberta : the pool price impact of Genesee Unit 3

International Nuclear Information System (INIS)

Topping, D.

2003-01-01

Alberta power pool prices for year 2000 were reviewed. The model assumptions were: studies based on PROSYM market simulations; base-load units offered at incremental cost; and, considerations in those cases where system gas units were modeled as coal units. The current situation in Alberta was reviewed. The Genesee 3 coal-fired facility is expected to be completed in the Winter 2004-2005 with an efficiency of 8 to 18 per cent better than other coal units. A graph was shown to examine the expected impact of Genesee 3 on Alberta prices. Electricity prices would increase during the period 2005-2008 without Genesee 3. Alberta prices are affected by factors such as: load-resource balance, fuel prices, cost of new capacity, offer strategy, available transmission, and tie lines. A capacity surplus is expected for the period 2003-2008. In addition, good correlation is expected for pool prices with gas prices. With Genesee 3 in operation, lower pool prices are expected in Alberta. figs

Self-formed waterfall plunge pools in homogeneous rock

Science.gov (United States)

Scheingross, Joel S.; Lo, Daniel Y.; Lamb, Michael P.

2017-01-01

Waterfalls are ubiquitous, and their upstream propagation can set the pace of landscape evolution, yet no experimental studies have examined waterfall plunge pool erosion in homogeneous rock. We performed laboratory experiments, using synthetic foam as a bedrock simulant, to produce self-formed waterfall plunge pools via particle impact abrasion. Plunge pool vertical incision exceeded lateral erosion by approximately tenfold until pools deepened to the point that the supplied sediment could not be evacuated and deposition armored the pool bedrock floor. Lateral erosion of plunge pool sidewalls continued after sediment deposition, but primarily at the downstream pool wall, which might lead to undermining of the plunge pool lip, sediment evacuation, and continued vertical pool floor incision in natural streams. Undercutting of the upstream pool wall was absent, and our results suggest that vertical drilling of successive plunge pools is a more efficient waterfall retreat mechanism than the classic model of headwall undercutting and collapse in homogeneous rock.

Patent pools: Intellectual property rights and competition.

NARCIS (Netherlands)

Rodriguez, V.F.

2010-01-01

Patent pools do not correct all problems associated with patent thickets. In this respect, patent pools might not stop the outsider problem from striking pools. Moreover, patent pools can be expensive to negotiate, can exclude patent holders with smaller numbers of patents or enable a group of major

A Study on Rack Thickness Effect for Spent Fuel Pool Storage

International Nuclear Information System (INIS)

Kim, Mi Jin; Lee, Hee-Jae; Sohn, Dong-Seong

2015-01-01

For the effective storage of used fuel, the development of high performance neutron absorbing materials is needed. One of the major concern for the used fuel storage is the assurance to keep subcriticality of the storage rack and the high performance neutron absorbing material is the vital part to assure this requirement. According to NRC guide line, the k-effective of the spent fuel storage racks must not exceed 0.95. To ensure its safety, subcriticality analysis is required. Subcriticality analysis of the used storage in spent fuel pool have been performed by different authors. Criticality calculations for light water reactor spent fuel storage rack were carried out by Jae et al. They used AMPX-KENO IV code and considered the effect of rack pitch and rack thickness for consolidated fuel. The criticality analysis has performed at Gd 0.2 and 1 wt% according to thickness change. As thickness increases, the volume of the spent fuel pool rack increases. Therefore, absorbing material also increases according to thickness

A Study on Rack Thickness Effect for Spent Fuel Pool Storage

Energy Technology Data Exchange (ETDEWEB)

Kim, Mi Jin; Lee, Hee-Jae; Sohn, Dong-Seong [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

2015-05-15

For the effective storage of used fuel, the development of high performance neutron absorbing materials is needed. One of the major concern for the used fuel storage is the assurance to keep subcriticality of the storage rack and the high performance neutron absorbing material is the vital part to assure this requirement. According to NRC guide line, the k-effective of the spent fuel storage racks must not exceed 0.95. To ensure its safety, subcriticality analysis is required. Subcriticality analysis of the used storage in spent fuel pool have been performed by different authors. Criticality calculations for light water reactor spent fuel storage rack were carried out by Jae et al. They used AMPX-KENO IV code and considered the effect of rack pitch and rack thickness for consolidated fuel. The criticality analysis has performed at Gd 0.2 and 1 wt% according to thickness change. As thickness increases, the volume of the spent fuel pool rack increases. Therefore, absorbing material also increases according to thickness.

Experimental and computational analysis of the hot water layer for the radiological protection in swimming pool reactor

International Nuclear Information System (INIS)

Ribeiro, Rogerio.

1995-01-01

Pool reactors are research reactors, which allow easy access to the core and rare simple to operate. Reactors of this kind operating at power levels higher than about one megawatt need a hot water layer at the surface of the pool, in order to keep surface activity below acceptable levels and enable free access to the upper part of the reactor. An experimental apparatus was constructed to study the hot water layer stability. Thermocouples were used to measure the temperature field. A numerical analysis was conducted simultaneously. Regarding experimental results, representative temperature contour lines of the hot water layer were plotted. The temperature field was determined in the numerical analysis and temperature contour lines corresponding to those of the experimental results were plotted. The hot water layer kept stable for experimental and numerical results. Good agreement between the results for the hot water layer position and thickness has been obtained. (author). 21 refs., 40 figs., 15 tabs

13 CFR 120.1705 - Pool formation requirements.

Science.gov (United States)

2010-01-01

... requirements. SBA may adjust the Pool characteristics periodically based on program experience and market... a Pool involving a Pool Loan it does not own, it must purchase the Loan Interest it proposes to pool... purchase the Loan Interest and take it into inventory or settle the purchase of the Loan Interest through...

Seismic analysis of large pools

Energy Technology Data Exchange (ETDEWEB)

Dong, R.G.; Tokarz, F.J.

1976-11-17

Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated.

Seismic analysis of large pools

International Nuclear Information System (INIS)

Dong, R.G.; Tokarz, F.J.

1976-01-01

Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated

1968 Listing of Swimming Pool Equipment.

Science.gov (United States)

National Sanitation Foundation, Ann Arbor, MI. Testing Lab.

An up-to-date listing of swimming pool equipment including--(1) companies authorized to display the National Sanitation Foundation seal of approval, (2) equipment listed as meeting NSF swimming pool equipment standards relating to diatomite type filters, (3) equipment listed as meeting NSF swimming pool equipment standard relating to sand type…

A strategy for optimizing item-pool management

NARCIS (Netherlands)

Ariel, A.; van der Linden, Willem J.; Veldkamp, Bernard P.

2006-01-01

Item-pool management requires a balancing act between the input of new items into the pool and the output of tests assembled from it. A strategy for optimizing item-pool management is presented that is based on the idea of a periodic update of an optimal blueprint for the item pool to tune item

Swimming Pools and Molluscum Contagiosum

Science.gov (United States)

... Travelers’ Health: Smallpox & Other Orthopoxvirus-Associated Infections Poxvirus Swimming Pools Recommend on Facebook Tweet Share Compartir The ... often ask if molluscum virus can spread in swimming pools. There is also concern that it can ...

Pooling and correlated neural activity

Directory of Open Access Journals (Sweden)

Robert Rosenbaum

2010-04-01

Full Text Available Correlations between spike trains can strongly modulate neuronal activity and affect the ability of neurons to encode information. Neurons integrate inputs from thousands of afferents. Similarly, a number of experimental techniques are designed to record pooled cell activity. We review and generalize a number of previous results that show how correlations between cells in a population can be amplified and distorted in signals that reflect their collective activity. The structure of the underlying neuronal response can significantly impact correlations between such pooled signals. Therefore care needs to be taken when interpreting pooled recordings, or modeling networks of cells that receive inputs from large presynaptic populations. We also show that the frequently observed runaway synchrony in feedforward chains is primarily due to the pooling of correlated inputs.

Method of measuring a liquid pool volume

Science.gov (United States)

Garcia, G.V.; Carlson, N.M.; Donaldson, A.D.

1991-03-19

A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools is disclosed, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid. 3 figures.

Design and Construction of Pool Door for Research Reactor

Energy Technology Data Exchange (ETDEWEB)

Jung, Kwangsub; Lee, Sangjin; Choi, Jinbok; Oh, Jinho; Lee, Jongmin [KAERI, Daejeon (Korea, Republic of)

2016-05-15

The pool door is a structure to isolate the reactor pool from the service pool for maintenance. The pool door is installed before the reactor pool is drained. The pool door consists of structural component and sealing component. The main structures of the pool door are stainless steel plates and side frames. The plates and frames are assembled by welded joints. Lug is welded at the top of the plate. The pool door is submerged in the pool water when it is used. Materials of the pool door should be resistive to corrosion and radiation. Stainless steel is used in structural components and air nozzle assemblies. Features of design and construction of the pool door for the research reactor are introduced. The pool door is designed to isolate the reactor pool for maintenance. Structural analysis is performed to evaluate the structural integrity during earthquake. Tests and inspections are also carried out during construction to identify the safety and function of the pool door.

Design and Construction of Pool Door for Research Reactor

International Nuclear Information System (INIS)

Jung, Kwangsub; Lee, Sangjin; Choi, Jinbok; Oh, Jinho; Lee, Jongmin

2016-01-01

The pool door is a structure to isolate the reactor pool from the service pool for maintenance. The pool door is installed before the reactor pool is drained. The pool door consists of structural component and sealing component. The main structures of the pool door are stainless steel plates and side frames. The plates and frames are assembled by welded joints. Lug is welded at the top of the plate. The pool door is submerged in the pool water when it is used. Materials of the pool door should be resistive to corrosion and radiation. Stainless steel is used in structural components and air nozzle assemblies. Features of design and construction of the pool door for the research reactor are introduced. The pool door is designed to isolate the reactor pool for maintenance. Structural analysis is performed to evaluate the structural integrity during earthquake. Tests and inspections are also carried out during construction to identify the safety and function of the pool door

Structural integrity assessment of HANARO pool cover

International Nuclear Information System (INIS)

Ryu, Jeong Soo

2001-11-01

This report is for the seismic analysis and the structural integrity evaluation of HANARO Pool Cover in accordances with the requirement of the Technical Specification for Seismic Analysis of HANARO Pool Cover. For performing the seismic analysis and evaluating the structural integrity for HANARO Pool Cover, the finite element analysis model using ANSYS 5.7 was developed and the dynamic characteristics were analyzed. The seismic response spectrum analyses of HANARO Pool Cover under the design floor response spectrum loads of OBE and SSE were performed. The analysis results show that the stress values in HANARO Pool Cover for the seismic loads are within the ASME Code limits. It is also confirmed that the fatigue usage factor is less than 1.0. Therefore any damage on structural integrity is not expected when an HANARO Pool Cover is installed in the upper part of the reactor pool

Collaborative Car Pooling System

OpenAIRE

João Ferreira; Paulo Trigo; Porfírio Filipe

2009-01-01

This paper describes the architecture for a collaborative Car Pooling System based on a credits mechanism to motivate the cooperation among users. Users can spend the accumulated credits on parking facilities. For this, we propose a business model to support the collaboration between a car pooling system and parking facilities. The Portuguese Lisbon-s Metropolitan area is used as application scenario.

Strain-specific and pooled genome sequences for populations of Drosophila melanogaster from three continents.

Science.gov (United States)

Bergman, Casey M; Haddrill, Penelope R

2015-01-01

To contribute to our general understanding of the evolutionary forces that shape variation in genome sequences in nature, we have sequenced genomes from 50 isofemale lines and six pooled samples from populations of Drosophila melanogaster on three continents. Analysis of raw and reference-mapped reads indicates the quality of these genomic sequence data is very high. Comparison of the predicted and experimentally-determined Wolbachia infection status of these samples suggests that strain or sample swaps are unlikely to have occurred in the generation of these data. Genome sequences are freely available in the European Nucleotide Archive under accession ERP009059. Isofemale lines can be obtained from the Drosophila Species Stock Center.

Life cycle environmental implications of residential swimming pools.

Science.gov (United States)

Forrest, Nigel; Williams, Eric

2010-07-15

Ownership of private swimming pools in the U.S. grew 2 to 4% per annum from 1997 to 2007. The environmental implications of pool ownership are analyzed by hybrid life cycle assessment (LCA) for nine U.S. cities. An operational model is constructed estimating consumption of chemicals, water, and energy for a typical residential pool. The model incorporates geographical climatic variations and upstream water and energy use from electricity and water supply networks. Results vary considerably by city: a factor of 5-6 for both water and energy use. Water use is driven by aridness and length of the swimming season, while energy use is mainly driven by length of the swimming season. Water and energy impacts of pools are significant, particularly in arid climates. In Phoenix for example pools account for 22% and 13% of a household's electricity and water use, respectively. Measures to reduce water and energy use in pools such as optimizing the pump schedule and covering the pool in winter can realize greater savings than many common household efficiency improvements. Private versus community pools are also compared. Community pools in Phoenix use 60% less swimming pool water and energy per household than subdivisions without community pools.

Structure for nuclear fuel storage pools

International Nuclear Information System (INIS)

Ebata, Sakae; Nichiei, Shinji.

1979-01-01

Purpose: To enable leak detection in nuclear fuel storage pools, as well as prevent external leakages while keeping the strength of the constructional structures. Constitution: Protection plates are provided around pool linear plates and a leak reception is provided to the bottom. Leakages are detected by leak detecting pipeways and the external leakages are prevented by collecting them in a detection area provided in the intermediate layer. Since ferro-reinforcements at the bottom wall of the pool are disconnected by the protection plate making it impossible to form the constructional body, body hunches are provided to the bottom wall of the pool for processing the ferro-reinforcements. (Yoshino, Y.)

Safety System for Controlling Fluid Flow into a Suction Line

Science.gov (United States)

England, John Dwight (Inventor); Kelley, Anthony R. (Inventor); Cronise, Raymond J. (Inventor)

2018-01-01

A safety system includes a sleeve fitted within a pool's suction line at its inlet. The sleeve terminates with a plate that resides within the suction line. The plate has holes formed therethrough. A housing defining distinct channels is fitted in the sleeve so that the distinct channels lie within the sleeve. Each of the distinct channels has a first opening on one end thereof and a second opening on another end thereof. The second openings reside in the sleeve. The first openings are in fluid communication with the water in the pool, and are distributed around a periphery of an area of the housing that prevents coverage of all the first openings when a human interacts therewith. A first sensor is coupled to the sleeve to sense pressure therein, and a second pressure sensor is coupled to the plate to sense pressure in one of the plates' holes.

Spent fuel pool cleanup and stabilization

International Nuclear Information System (INIS)

Miller, R.L.

1987-06-01

Each of the plutonium production reactors at Hanford had a large water-filled spent fuel pool to provide interim storage of irradiated fuel while awaiting shipment to the separation facilities. After cessation of reactor operations the fuel was removed from the pools and the water levels were drawn down to a 5- to 10-foot depth. The pools were maintained with the water to provide shielding and radiological control. What appeared to be a straightforward project to process the water, remove the sediments from the basin, and stabilize the contamination on the floors and walls became a very complex and time consuming operation. The sediment characteristics varied from pool to pool, the ion exchange system required modification, areas of hard-pack sediments were discovered on the floors, special arrangements to handle and package high dose rate items for shipment were required, and contract problems ensued with the subcontractor. The original schedule to complete the project from preliminary engineering to final stabilization of the pools was 15 months. The actual time required was about 25 months. The original cost estimate to perform the work was $2,651,000. The actual cost of the project was $5,120,000, which included $150,000 for payment of claims to the subcontractor. This paper summarizes the experiences associated with the cleanup and radiological stabilization of the 100-B, -C, -D, and -DR spent fuel pools, and discusses a number of lessons learned items

Evaporation-preventive device for nuclear reactor pool water

International Nuclear Information System (INIS)

Kurusu, Yoshihisa; Akabori, Shiro.

1986-01-01

Purpose: To prevent pool water from evaporating by a great amount in a reactor pool such as a spent fuel storing pool. Constitution: Air discharge and in-take ports are disposed just above the surface of the pool water and charge and discharge of airs are forcively carried out to form air curtains above the pool water. Water vapor evaporated from the surface of the pool water does not diffuse above the air curtains due to the air stream of the curtains, but is intaken into the intake port and then condensated into water by a steam condensator and re-supplied to the pool. Since diffusion of water vapor and radioactive materials are suppressed above the air curtains, the working circumstance in the pool chamber can be maintained desirably thereby keeping the radioactivity dose in the atmosphere. Further, incorporation of dusts from above into the pool can also be prevented by the air curtains to provide an effect for the prevention of radioactive contamination. Further, since covers are not used, visual observation can be insured. (Kawakami, Y.)

Ripples in a superconducting tidal pool

CERN Document Server

Hudson, E

2003-01-01

The behaviour of electrons in a metal is often compared to that of water in a pool. An empty pool is like a material that has all of its electrons removed. As electrons are 'poured' into the metal, they first occupy the lowest energies available - the bottom of the pool - and eventually fill up to the Fermi energy, the top of the pool. At this point we no longer discuss electrons but quasiparticles. These are electrons that have modified properties due to their interactions within the material. Waves in a pool can be excited, and their properties will depend on the depth of the water. Similarly in a metal, quasiparticles behave like waves that have a material-dependent dispersion relation between their energy and their wavevector, which specifies their direction and wavelength. This simple analogy also hints at an indirect method of measuring the dispersion relation of a metal, and hence the myriad of properties that depend on it. (U.K.)

Swimming pools as heat sinks for air conditioners: Model design and experimental validation for natural thermal behavior of the pool

Energy Technology Data Exchange (ETDEWEB)

Woolley, Jonathan; Harrington, Curtis; Modera, Mark [University of California Davis, Western Cooling Efficiency Center, 1450 Drew Avenue, Suite 100, Davis, CA 95618 (United States)

2011-01-15

Swimming pools as thermal sinks for air conditioners could save approximately 40% on peak cooling power and 30% of overall cooling energy, compared to standard residential air conditioning. Heat dissipation from pools in semi-arid climates with large diurnal temperature shifts is such that pool heating and space cooling may occur concurrently; in which case heat rejected from cooling equipment could directly displace pool heating energy, while also improving space cooling efficiency. The performance of such a system relies on the natural temperature regulation of swimming pools governed by evaporative and convective heat exchange with the air, radiative heat exchange with the sky, and conductive heat exchange with the ground. This paper describes and validates a model that uses meteorological data to accurately predict the hourly temperature of a swimming pool to within 1.1 C maximum error over the period of observation. A thorough review of literature guided our choice of the most appropriate set of equations to describe the natural mass and energy exchange between a swimming pool and the environment. Monitoring of a pool in Davis, CA, was used to confirm the resulting simulations. Comparison of predicted and observed pool temperature for all hours over a 56 day experimental period shows an R-squared relatedness of 0.967. (author)

Generalizing Pooling Functions in CNNs: Mixed, Gated, and Tree.

Science.gov (United States)

Lee, Chen-Yu; Gallagher, Patrick; Tu, Zhuowen

2018-04-01

In this paper, we seek to improve deep neural networks by generalizing the pooling operations that play a central role in the current architectures. We pursue a careful exploration of approaches to allow pooling to learn and to adapt to complex and variable patterns. The two primary directions lie in: (1) learning a pooling function via (two strategies of) combining of max and average pooling, and (2) learning a pooling function in the form of a tree-structured fusion of pooling filters that are themselves learned. In our experiments every generalized pooling operation we explore improves performance when used in place of average or max pooling. We experimentally demonstrate that the proposed pooling operations provide a boost in invariance properties relative to conventional pooling and set the state of the art on several widely adopted benchmark datasets. These benefits come with only a light increase in computational overhead during training (ranging from additional 5 to 15 percent in time complexity) and a very modest increase in the number of model parameters (e.g., additional 1, 9, and 27 parameters for mixed, gated, and 2-level tree pooling operators, respectively). To gain more insights about our proposed pooling methods, we also visualize the learned pooling masks and the embeddings of the internal feature responses for different pooling operations. Our proposed pooling operations are easy to implement and can be applied within various deep neural network architectures.

Using pooled budgets to integrate health and welfare services: a comparison of experiments in England and Sweden.

Science.gov (United States)

Hultberg, Eva-Lisa; Glendinning, Caroline; Allebeck, Peter; Lönnroth, Knut

2005-11-01

The lack of collaboration between health, social and other welfare services is believed to impair efficiency and reduce effectiveness in addressing the complex problems of patients. Differences in funding streams, political accountabilities, organisational structures and professional cultures are all alleged to contribute to barriers between services. Drawing on their respective evaluations, this paper describes experiments in England and Sweden that use pooled budgets between services to improve interagency and interprofessional collaboration and presents evidence on their impact. Despite differences in the funding and organisation of health and welfare services in each country, some similar conclusions are reached. Among senior managers and politicians, budget pooling broadened their awareness of interdependencies with other agencies and professionals in promoting patients' welfare. However, these broadened perspectives were not immediately shared by professionals working at the front line, with whom patients had immediate contact. Moreover, neither experiment yielded unequivocal evidence of improved cost-effectiveness or of the benefits of budget pooling on the outcomes for service users. These experiments also raise questions about the equity and accountability of welfare services because in both countries only a limited range of services has been integrated under the umbrella of the pooled budgets.

Technical specification for fabrication of HANARO pool cover

Energy Technology Data Exchange (ETDEWEB)

Ryu, Jeong Soo; Woo, Sang Ik

2001-06-01

This technical specification details the requirements and the acceptance criteria for design, seismic analysis, function test, installation and quality assurance for HANARO pool cover which will be installed at the top of reactor pool. The pool cover is classified as non-nuclear safety, seismic category II and quality class T. The basic design of the pool cover for increasing HANARO applications has been carried out for supporting the driving devices which can load, unload and rotate the irradiation targets in the in-core and out-core vertical irradiation holes under on-power operation. The comments of HANARO user group related with irradiation tests have optimally considered in the process of design. The interference between fuel handling and control absorber units in the reactor pool and activities to load, unload and rotate the irradiation targets at the top of the reactor pool have been minimized. The pool cover can be moved for maintenance and can protect the reactor pool from unexpected drop of foreign materials. It provides the space to vertical access of driving devices for NTD, CT/IR and OR4/OR5 under on-power operation. And the pool cover assembly must maintain its structural integrity under seismic load. Based on the above design concept, the HANARO pool cover has been proposed as supporting structure of driving devices for NTD, fission moly and RI production under on-power operation.

The CRDL model of SSC-K code for the safety improvement of a pool-type liquid metal-cooled reactor

International Nuclear Information System (INIS)

Jung, H. Y.; Ha, K. S.; Jang, W. P.; Hu, S.; Lee, Y. B.

2004-01-01

With the increased thermal power of KALIMER-600, it becomes important to model accurately the reactivity feedback effects due to the thermal expansion of a fuel rod and internal structure during a transient. In KALIMER design, the fuel axial expansion, core radial expansion, and the control rod drive line/reactor vessel (CRDL/RV) thermal expansion are the important reactivity feedback mechanisms. It is required to develop a more detailed CRDL/RV model for the accurate analysis of the KALIMER-600 transient because the control rod drive line of 9.5 m is immersed in the hot pool. For this a new CRDL/RV model was developed to model the effect of expansion of CRDL utilizing the temperature distribution obtained with the hot-pool 2-D model of SSC-K code. It is estimated that the developed model describes more realistically the negative reactivity insertion effect due to the initial temperature change during the UTOP transient of KALIMER-150

Decontamination of outdoor school swimming pools in Fukushima

International Nuclear Information System (INIS)

Saegusa, Jun

2013-01-01

After the Fukushima Daiichi NPP accident following the Great East Japan Earthquake, many school swimming pools in Fukushima have suspended water discharge, due to concerns that pool water which contains radioactive fallout is discharged into a river or waterway for agricultural use. The Japan Atomic Energy Agency conducted researches and examinations on the existing absorbent method and the flocculation method as ways for decontaminating pool water. By reviewing and improving these methods through decontamination demonstrations at eight pools in Fukushima, a practical decontamination method for outdoor pools has been established. This report summarizes the methods and results of the decontamination demonstrations carried out at the schools. Also, the surface density of fallout estimated at one of the pools is also presented and discussed in connection with the overall collection ratio of radiocesium at the pool. (author)

48 CFR 873.114 - Best value pool.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Best value pool. 873.114... SUPPLEMENTARY REGULATIONS SIMPLIFIED ACQUISITION PROCEDURES FOR HEALTH-CARE RESOURCES 873.114 Best value pool... solicitation. These vendors constitute the best value pool. This determination is within the sole discretion of...

Biodiversity of 52 chicken populations assessed by microsatellite typing of DNA pools

Directory of Open Access Journals (Sweden)

Thomson Pippa

2003-09-01

Full Text Available Abstract In a project on the biodiversity of chickens funded by the European Commission (EC, eight laboratories collaborated to assess the genetic variation within and between 52 populations from a wide range of chicken types. Twenty-two di-nucleotide microsatellite markers were used to genotype DNA pools of 50 birds from each population. The polymorphism measures for the average, the least polymorphic population (inbred C line and the most polymorphic population (Gallus gallus spadiceus were, respectively, as follows: number of alleles per locus, per population: 3.5, 1.3 and 5.2; average gene diversity across markers: 0.47, 0.05 and 0.64; and proportion of polymorphic markers: 0.91, 0.25 and 1.0. These were in good agreement with the breeding history of the populations. For instance, unselected populations were found to be more polymorphic than selected breeds such as layers. Thus DNA pools are effective in the preliminary assessment of genetic variation of populations and markers. Mean genetic distance indicates the extent to which a given population shares its genetic diversity with that of the whole tested gene pool and is a useful criterion for conservation of diversity. The distribution of population-specific (private alleles and the amount of genetic variation shared among populations supports the hypothesis that the red jungle fowl is the main progenitor of the domesticated chicken.

Development of a Two-dimensional Thermohydraulic Hot Pool Model and ITS Effects on Reactivity Feedback during a UTOP in Liquid Metal Reactors

International Nuclear Information System (INIS)

Lee, Yong Bum; Jeong, Hae Yong; Cho, Chung Ho; Kwon, Young Min; Ha, Kwi Seok; Chang, Won Pyo; Suk, Soo Dong; Hahn, Do Hee

2009-01-01

The existence of a large sodium pool in the KALIMER, a pool-type LMR developed by the Korea Atomic Energy Research Institute, plays an important role in reactor safety and operability because it determines the grace time for operators to cope with an abnormal event and to terminate a transient before reactor enters into an accident condition. A two-dimensional hot pool model has been developed and implemented in the SSC-K code, and has been successfully applied for the assessment of safety issues in the conceptual design of KALIMER and for the analysis of anticipated system transients. The other important models of the SSC-K code include a three-dimensional core thermal-hydraulic model, a reactivity model, a passive decay heat removal system model, and an intermediate heat transport system and steam generation system model. The capability of the developed two-dimensional hot pool model was evaluated with a comparison of the temperature distribution calculated with the CFX code. The predicted hot pool coolant temperature distributions obtained with the two-dimensional hot pool model agreed well with those predicted with the CFX code. Variations in the temperature distribution of the hot pool affect the reactivity feedback due to an expansion of the control rod drive line (CRDL) immersed in the pool. The existing CRDL reactivity model of the SSC-K code has been modified based on the detailed hot pool temperature distribution obtained with the two-dimensional pool model. An analysis of an unprotected transient over power with the modified reactivity model showed an improved negative reactivity feedback effect

Two endornaviruses show differential infection patterns between gene pools of Phaseolus vulgaris.

Science.gov (United States)

Khankhum, Surasak; Valverde, Rodrigo A; Pastor-Corrales, Marcial A; Osorno, Juan M; Sabanadzovic, Sead

2015-04-01

We investigated the occurrence of two plant endornaviruses, Phaseolus vulgaris endornavirus 1 and Phaseolus vulgaris endornavirus 2, in breeding lines, cultivars, landraces, and wild genotypes of common bean (Phaseolus vulgaris) collected from the two centers of common bean domestication: Mesoamerica and the Andes. The two endornaviruses were detected in many genotypes of Mesoamerican origin but rarely in genotypes of Andean origin. The results suggest that these two endornaviruses were introduced into the Mesoamerican modern genotypes during common bean domestication and provide more evidence for the existence of two divergent gene pools of common bean.

Delineating probabilistic species pools in ecology and biogeography

OpenAIRE

Karger, Dirk Nikolaus; Cord, Anna F; Kessler, Michael; Kreft, Holger; Kühn, Ingolf; Pompe, Sven; Sandel, Brody; Sarmento Cabral, Juliano; Smith, Adam B; Svenning, Jens-Christian; Tuomisto, Hanna; Weigelt, Patrick; Wesche, Karsten

2016-01-01

Aim To provide a mechanistic and probabilistic framework for defining the species pool based on species-specific probabilities of dispersal, environmental suitability and biotic interactions within a specific temporal extent, and to show how probabilistic species pools can help disentangle the geographical structure of different community assembly processes. Innovation Probabilistic species pools provide an improved species pool definition based on probabilities in conjuncti...

Pool water cleaning facility

Energy Technology Data Exchange (ETDEWEB)

Yoshikawa, Kazuhiro; Kinoshita, Shoichiro [Hitachi Ltd., Tokyo (Japan); Asano, Takashi

1998-05-29

Only one system comprising a suppression poor water cleaning system (SPCU) and a filtration desalting tower (F/D) is connected for a plurality of nuclear power plants. Pipelines/valves for connecting the one system of the SPCU pump, the F/D and the plurality of nuclear power plants are disposed, and the system is used in common with the plurality of nuclear power plants. Pipelines/valves for connecting a pipeline for passing SP water to the commonly used SPCU pump and a skimmer surge tank are disposed, and fuel pool water is cooled and cleaned by the commonly used SPCU pump and the commonly used F/D. The number of SPCU pumps and the F/D facilities can be reduced, and a fuel pool water cooling operation mode and a fuel pool water cleaning operation mode which were conducted by an FPC pump so far are conducted by the SPCU pump. (N.H.)

Current operating practices of nuclear insurance pools

International Nuclear Information System (INIS)

O'Connell, J.M.

1993-01-01

This paper discusses the nuclear pooling system and co-operation between the pools, present practice and capacity, with a breakdown of the limits for third party liability and material damage. The author also describes the relationship between the pools and the nuclear operators (the policyholders), and concludes that the nuclear pools have been successful in serving the interests of their member companies, their policyholders and the governments as they have provided a stable insurance market by making available capacity in amounts that had never before been assembled and placed at risk in a single location. 2 tabs

Heat transfer from internally heated hemispherical pools

International Nuclear Information System (INIS)

Gabor, J.D.; Ellsion, P.G.; Cassulo, J.C.

1980-01-01

Experiments were conducted on heat transfer from internally heated ZnSO 4 -H 2 O pools to the walls of hemispherical containers. This experimental technique provides data for a heat transfer system that has to date been only theoretically treated. Three different sizes of copper hemispherical containers were used: 240, 280, 320 mm in diameter. The pool container served both as a heat transfer surface and as an electrode. The opposing electrode was a copper disk, 50 mm in diameter located at the top of the pool in the center. The top surface of the pool was open to the atmosphere

Cooling device for reactor suppression pool

International Nuclear Information System (INIS)

Togasaki, Susumu; Kato, Kiyoshi.

1994-01-01

In a cooling device of a reactor suppression pool, when a temperature of pool water is abnormally increased and a heat absorbing portion is heated by, for example, occurrence of an accident, coolants are sent to the outside of the reactor container to actuates a thermally operating portion by the heat energy of coolants and drive heat exchanging fluids of a secondary cooling system. If the heat exchanging fluids are sent to a cooling portion, the coolants are cooled and returned to the heat absorbing portion of the suppression pool water. If the heat absorbing portion is heat pipes, the coolants are evaporated by heat absorbed from the suppression pool water, steams are sent to the thermally operating portion, then coolants are liquefied and caused to return to the heat absorbing portion. If the thermal operation portion is a gas turbine, the gas turbine is operated by the coolants, and it is converted to a rotational force to drive heat exchanging fluids by pumps. By constituting the cooling portion with a condensator, the coolants are condensed and liquefied and returned to the heat absorbing portion of the suppression pool water. (N.H.)

Structure of pool in reactor building

International Nuclear Information System (INIS)

Yokoyama, Shigeki.

1997-01-01

Shielding walls made of iron-reinforced concrete having a metal liner including two body walls rigidly combined to the upper surface of a reactor container are disposed at least to one of an equipment pool or spent fuel storage pool in a reactor building. A rack for temporarily placing an upper lattice plate is detachably attached at least above one of a steam dryer or a gas/liquid separator temporarily placed in the temporary pool, and the height from the bottom portion to the upper end of the shielding wall is determined based on the height of an upper lattice plate temporary placed on the rack and the water depth required for shielding radiation from the upper lattice plate. An operator's exposure on the operation floor can be reduced by the shielding wall, and radiation dose from the spent fuels is reduced. The increase of the height of a pool guarder enhances bending resistance as a ceiling. In addition, the total height of them is made identical with the depth of the spent fuel storage pool thereby enabling to increase storage area for spent fuels. (N.H.)

School Discipline in the Dark: Crippling Court Confusion Offers Mixed Messages for School Administrators Attempting to Discipline Students for Cyber Misconduct

Science.gov (United States)

Summers, Beth A.

2013-01-01

This dissertation examines the demarcation line of school authority between off campus conduct and on campus discipline involving student cyber speech. A lack of clear direction from the Supreme court has left school administrators wading through a quagmire of advice and disparate lower court rulings regarding their authority to punish students…

Pool gateway seal

International Nuclear Information System (INIS)

Starr, J.A.; Steinert, L.A.

1983-01-01

A device for sealing a gateway between interconnectable pools in a nuclear facility comprising a frame supporting a liquid impermeable sheet positioned in a u-shaped gateway between the pools. An inflatable tube carried in a channel in the periphery of the frame and adjoining the gateway provides a seal therebetween when inflated. A restraining arrangement on the bottom edge of the frame is releasably engagable with an adjacent portion of the gateway to restrict the movement of the frame in the u-shaped gateway upon inflation of the tube, thereby enhancing the seal. The impermeable sheet is formed of an elastomer and thus is conformable to a liquid permeable supportive wall upon application of liquid pressure to the side of the sheet opposite the wall

Recent advances in probabilistic species pool delineations

Directory of Open Access Journals (Sweden)

Dirk Nikolaus Karger

2016-07-01

Full Text Available A species pool is the set of species that could potentially colonize and establish within a community. It has been a commonly used concept in biogeography since the early days of MacArthur and Wilson’s work on Island Biogeography. Despite their simple and appealing definition, an operational application of species pools is bundled with a multitude of problems, which have often resulted in arbitrary decisions and workarounds when defining species pools. Two recently published papers address the operational problems of species pool delineations, and show ways of delineating them in a probabilistic fashion. In both papers, species pools were delineated using a process-based, mechanistical approach, which opens the door for a multitude of new applications in biogeography. Such applications include detecting the hidden signature of biotic interactions, disentangling the geographical structure of community assembly processes, and incorporating a temporal extent into species pools. Although similar in their conclusions, both ‘probabilistic approaches’ differ in their implementation and definitions. Here I give a brief overview of the differences and similarities of both approaches, and identify the challenges and advantages in their application.

Chinese nuclear insurance and Chinese nuclear insurance pool

International Nuclear Information System (INIS)

Gong Zhiqi

2000-01-01

Chinese Nuclear Insurance Started with Daya Bay Nuclear Power Station, PICC issued the insurance policy. Nuclear insurance cooperation between Chinese and international pool's organizations was set up in 1989. In 1996, the Chinese Nuclear Insurance Pool was prepared. The Chinese Nuclear Insurance Pool was approved by The Chinese Insurance Regulatory Committee in May of 1999. The principal aim is to centralize maximum the insurance capacity for nuclear insurance from local individual insurers and to strengthen the reinsurance relations with international insurance pools so as to provide the high quality insurance service for Chinese nuclear industry. The Member Company of Chinese Nuclear Pool and its roles are introduced in this article

Guide for decontaminating swimming pool at schools

International Nuclear Information System (INIS)

Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

2012-07-01

Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

Guide for decontaminating swimming pool at schools

Energy Technology Data Exchange (ETDEWEB)

Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

2012-07-15

Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

(Important hygienic aspects for swimming pools (author's transl))

Energy Technology Data Exchange (ETDEWEB)

Somosi, G

1981-01-01

The major epidemics which occurred in Hungary and originated from water in swimming pools are reported. The difficulties encountered in producing epidemiological evidence and in monitoring infections originating from water in swimming pools are mentioned. The possibilities of controlling the water quality in swimming pools and of preventing infections are discussed. Reference is made to the existing bacteriological limit values in Hungary to be observed in the recirculation of water in swimming pools.

Studies of thermal stratification in water pool

International Nuclear Information System (INIS)

Verma, P.K.; Chandraker, D.K.; Nayak, A.K.; Vijayan, P.K.

2015-01-01

Large water pools are used as a heat sink for various cooling systems used in industry. In context of advance nuclear reactors like AHWR, it is used as ultimate heat sink for passive systems for decay heat removal and containment cooling. This system incorporates heat exchangers submerged in the large water pool. However, heat transfer by natural convection in pool poses a problem of thermal stratification. Due to thermal stratification hot layers of water accumulate over the relatively cold one. The heat transfer performance of heat exchanger gets deteriorated as a hot fluid envelops it. In the nuclear reactors, the walls of the pool are made of concrete and it may subject to high temperature due to thermal stratification which is not desirable. In this paper, a concept of employing shrouds around the heat source is studied. These shrouds provide a bulk flow in the water pool, thereby facilitating mixing of hot and cold fluid, which eliminate stratification. The concept has been applied to the a scaled model of Gravity Driven Water Pool (GDWP) of AHWR in which Isolation Condensers (IC) tubes are submerged for decay heat removal of AHWR using ICS and thermal stratification phenomenon was predicted with and without shrouds. To demonstrate the adequacy of the effectiveness of shroud arrangement and to validate the simulation methodology of RELAP5/Mod3.2, experiments has been conducted on a scaled model of the pool with and without shroud. (author)

Thermal analyses of solar swimming pool heating in Pakistan

International Nuclear Information System (INIS)

Ahmad, I.

2011-01-01

Hotels and swimming clubs in Pakistan pay huge gas bills for heating Swimming pools in winter. Winter days in most parts of Pakistan remain sunny and unglazed low cost solar collectors may be used to extend the swimming season. Installing the pool in a wind-protected area, which receives unobstructed solar radiation, may further reduce the size of the solar collectors required to heat the swimming pools. The pools should be covered with plastic sheet to eliminate evaporative heat losses and to prevent dust and tree leaves falling in the pool. The results of the thermal analysis show that in some parts of the country, a solar exposed pool can maintain comfortable temperature simply by using a plastic sheet on the pool surface. On the other hand, there are cities where solar collector array equal to twice the surface area of the pool is required to keep desired temperature in winter. (author)

Reduction of the pool-top radiation level in HANARO

International Nuclear Information System (INIS)

Lee, Choong-Sung; Park, Sang-Jun; Kim, Heonil; Park, Yong-Chul; Choi, Young-San

1999-01-01

HANARO is an open-tank-in-pool type reactor. Pool water is the only shielding to minimize the pool top radiation level. During the power ascension test of HANARO, the measured pool top radiation level was higher than the design value because some of the activation products in the coolant reached the pool surface. In order to suppress this rising coolant, the hot water layer system (HWL) was designed and installed to maintain l.2 meter-deep hot water layer whose temperature is 5degC higher than that of the underneath pool surface. After the installation of the HWL system, however, the radiation level of the pool-top did not satisfy the design value. The operation modes of the hot water layer system and the other systems in the reactor pool, which had an effect on the formation of the hot water layer, were changed to reduce pool-top radiation level. After the above efforts, the temperature and the radioactivity distribution in the pool was measured to confirm whether this system blocked the rising coolant. The radiation level at the pool-top was significantly reduced below one tenth of that before installing the HWL and satisfied the design value. It was also confirmed by calculation that this hot water layer system would significantly reduce the release of fission gases to the reactor hall and the environment during the hypothetical accident as well. (author)

17 CFR 4.22 - Reporting to pool participants.

Science.gov (United States)

2010-04-01

..., the financial statements are not required to include consolidated information for all series. (7) For... event that the International Financial Reporting Standards require consolidated financial statements for... reporting pool's consolidated financial statements. (ii) The commodity pool operator of a pool that meets...

Behavior of spent nuclear fuel in water pool storage

International Nuclear Information System (INIS)

Johnson, A.B. Jr.

1977-09-01

Storage of irradiated nuclear fuel in water pools (basins) has been standard practice since nuclear reactors first began operation approximately 34 years ago. Pool storage is the starting point for all other fuel storage candidate processes and is a candidate for extended interim fuel storage until policy questions regarding reprocessing and ultimate disposal have been resolved. This report assesses the current performance of nuclear fuel in pool storage, the range of storage conditions, and the prospects for extending residence times. The assessment is based on visits to five U.S. and Canadian fuel storage sites, representing nine storage pools, and on discussions with operators of an additional 21 storage pools. Spent fuel storage experience from British pools at Winfrith and Windscale and from a German pool at Karlsruhe (WAK) also is summarized

Condensation in a two-phase pool

International Nuclear Information System (INIS)

Duffey, R.B.; Hughes, E.D.

1991-01-01

We consider the case of vapor condensation in a liquid pool, when the heat transfer is controlled by heat losses through the walls. The analysis is based on drift flux theory for phase separation in the pool, and determines the two-phase mixture height for the pool. To our knowledge this is the first analytical treatment of this classic problem that gives an explicit result, previous work having established the result for the evaporative case. From conservation of mass and energy in a one-dimensional steady flow, together with a void relation between the liquid and vapor fluxes, we determine the increase in the mixture level from the base level of the pool. It can be seen that the thermal and hydrodynamic influences are separable. Thus, the thermal influence of the wall heat transfer appears through its effect on the condensing length L*, so that at high condensation rates the pool is all liquid, and at low rates overflows (the level swell or foaming effect). Similarly, the phase separation effect hydrodynamically determines the height via the relative velocity of the mixture to the entering flux. We examine some practical applications of this result to level swell in condensing flows, and also examine some limits in ideal cases

Welding pool measurement using thermal array sensor

Science.gov (United States)

Cho, Chia-Hung; Hsieh, Yi-Chen; Chen, Hsin-Yi

2015-08-01

Selective laser melting (SLM) is an additive manufacturing (AM) technology that uses a high-power laser beam to melt metal powder in chamber of inert gas. The process starts by slicing the 3D CAD data as a digital information source into layers to create a 2D image of each layer. Melting pool was formed by using laser irradiation on metal powders which then solidified to consolidated structure. In a selective laser melting process, the variation of melt pool affects the yield of a printed three-dimensional product. For three dimensional parts, the border conditions of the conductive heat transport have a very large influence on the melt pool dimensions. Therefore, melting pool is an important behavior that affects the final quality of the 3D object. To meet the temperature and geometry of the melting pool for monitoring in additive manufacturing technology. In this paper, we proposed the temperature sensing system which is composed of infrared photodiode, high speed camera, band-pass filter, dichroic beam splitter and focus lens. Since the infrared photodiode and high speed camera look at the process through the 2D galvanometer scanner and f-theta lens, the temperature sensing system can be used to observe the melting pool at any time, regardless of the movement of the laser spot. In order to obtain a wide temperature detecting range, 500 °C to 2500 °C, the radiation from the melting pool to be measured is filtered into a plurality of radiation portions, and since the intensity ratio distribution of the radiation portions is calculated by using black-body radiation. The experimental result shows that the system is suitable for melting pool to measure temperature.

A skeleton for distributed work pools in Eden

DEFF Research Database (Denmark)

Dieterle, Mischa; Berthold, Jost; Loogen, Rita

2010-01-01

We present a flexible skeleton for implementing distributed work pools in our parallel functional language Eden. The skeleton manages a pool of tasks (work pool) in a distributed manner using a demand-driven work stealing approach for load balancing. All coordination is done locally within...

Sustainability of common pool resources

OpenAIRE

Timilsina, Raja Rajendra; Kotani, Koji; Kamijo, Yoshio

2017-01-01

Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as "capitalism," affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepales...

The Nuclear Insurance Pools: Operations and Covers

International Nuclear Information System (INIS)

Tetley, M.

2008-01-01

Nuclear insurance pools have provided insurance for the nuclear industry for over fifty years and it is fair to say that the development of civil nuclear power would not have been possible without the support of the commercial insurance market. The unknown risks presented by the nascent nuclear power industry in the 1950s required a leap of faith by insurers who developed specialist pooled insurance capacity to ensure adequate capacity to back up the operators' compensation obligations. Since then, nuclear insurance pools have evolved to become comprehensive suppliers of most types of insurance for nuclear plant globally. This paper will outline the structure, development, products and current operations of nuclear insurance pools.(author)

Shedding Light on Dark Liquidity Pools

NARCIS (Netherlands)

Degryse, H.A.; van Achter, M.; Wuyts, G.

2008-01-01

This article reviews the recent developments on dark liquidity pools starting from the theoretical and empirical academic literature. The number of dark liquidity pools as well as their trading volume has grown substantially in the last couple of years. We highlight the incentives of providers as

NACUBO's Guide to Unitizing Investment Pools. Second Edition

Science.gov (United States)

Wheeler, Mary S.

2011-01-01

The National Association of College and University Business Officers' (NACUBO's) "Guide to Unitizing Investment Pools" addresses the principles and concepts for administering a consolidated investment pool. Unitization is the mechanism by which investment funds are pooled to maximize investment efficiencies and provide information for donors,…

Investigation of the condition of spent-fuel pool components

International Nuclear Information System (INIS)

Kustas, F.M.; Bates, S.O.; Opitz, B.E.; Johnson, A.B. Jr.; Perez, J.M. Jr.; Farnsworth, R.K.

1981-09-01

It is currently projected that spent nuclear fuel, which is discharged from the reactor and then stored in water pools, may remain in those pools for several decades. Other studies have addressed the expected integrity of the spent fuel during extended water storage; this study assesses the integrity of metallic spent fuel pool components. Results from metallurgical examinations of specimens taken from stainless steel and aluminum components exposed in spent fuel pools are presented. Licensee Event Reports (LERs) relating to problems with spent fuel components were assessed and are summarized to define the types of operational problems that have occurred. The major conclusions of this study are: aluminum and stainless steel spent fuel pool components have a good history of performance in both deionized and borated water pools. Although some operational problems involving pool components have occurred, these problems have had minimal impacts

Investigation of the condition of spent-fuel pool components

Energy Technology Data Exchange (ETDEWEB)

Kustas, F.M.; Bates, S.O.; Opitz, B.E.; Johnson, A.B. Jr.; Perez, J.M. Jr.; Farnsworth, R.K.

1981-09-01

It is currently projected that spent nuclear fuel, which is discharged from the reactor and then stored in water pools, may remain in those pools for several decades. Other studies have addressed the expected integrity of the spent fuel during extended water storage; this study assesses the integrity of metallic spent fuel pool components. Results from metallurgical examinations of specimens taken from stainless steel and aluminum components exposed in spent fuel pools are presented. Licensee Event Reports (LERs) relating to problems with spent fuel components were assessed and are summarized to define the types of operational problems that have occurred. The major conclusions of this study are: aluminum and stainless steel spent fuel pool components have a good history of performance in both deionized and borated water pools. Although some operational problems involving pool components have occurred, these problems have had minimal impacts.

Analysis of the loss of pool cooling accident in a PWR spent fuel pool with MAAP5

International Nuclear Information System (INIS)

Wu, Xiaoli; Li, Wei; Zhang, Yapei; Tian, Wenxi; Su, Guanghui; Qiu, Suizheng

2014-01-01

Highlights: • A PWR spent fuel pool was modeled by using MAAP5. • Loss of pool cooling severe accident scenarios were studied. • Loss of pool cooling accidents with two mitigation measures were analyzed. - Abstract: The Fukushima Daiichi nuclear accident shows that it is necessary to study potential severe accidents and corresponding mitigation measures for the spent fuel pool (SFP) of a nuclear power plant (NPP). This paper presents the analysis of loss of pool cooling accident scenarios and the discussion of mitigation measures for the SFP at a pressurized water reactor (PWR) NPP with the MAAP5 code. Analysis of uncompensated loss of water due to the loss of pool cooling with different initial pool water levels of 12.2 m (designated as a reference case) and 10.7 m have been performed based on a MAAP5 input model. Scenarios of the accident such as overheating of uncovered fuel assemblies, oxidation of claddings and hydrogen generation, loss of intactness of fuel rod claddings, and release of radioactive fission products were predicted with the assumption that mitigation measures were unavailable. The results covered a broad spectrum of severe accident evaluations in the SFP. Furthermore, as important mitigation measures, the effects of recovering the SFP cooling system and makeup water in SFP on the accident progressions have also been investigated respectively based on the events of pool water boiling and spent fuels uncovery. Based upon the reference case, three cases with the recovery of SFP cooling system and three other cases with makeup water in SFP have been studied. The results showed that, severe accident might happen if SFP cooling system was not restored timely before the spent fuels started to become uncovered; spent fuels could be completely submerged and severe accident might be avoided if SFP makeup water system provided water with a mass flow rate larger than the average evaporation rate defined as the division of pool water mass above the

Swimming-pool piles; Piles piscines

Energy Technology Data Exchange (ETDEWEB)

Trioulaire, M [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1959-07-01

In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10{sup 13}. This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [French] En France, deux piles piscines, Melusine et Triton, viennent d'entrer en service. La pile piscine est l'outil de recherche ideal pour des flux de neutrons de l'ordre de 10{sup 13}. Ce type de pile peut interesser des maintenant de nombreux centres de recherches mais il faut reduire son prix de revient et rompre avec le conformisme de sa conception. Il y a avantage: - a enterrer la piscine; - a supprimer les canaux experimentaux; - a concentrer le circuit de refrigeration dans la piscine; - a effectuer toutes les manipulations dans l'eau; - a doubler le coeur. (auteur)

Plant diversity associated with pools in natural and restored peatlands

Directory of Open Access Journals (Sweden)

N. Fontaine

2007-06-01

Full Text Available This study describes plant assemblages associated with the edges of peatland pools. We conducted inventories in six natural peatlands in the province of Québec (Canada in order to measure the contribution of pools to species diversity in climatic regions where peatlands are used for peat extraction. We also carried out vegetation surveys in a peatland that has been restored after peat extraction/harvesting to determine whether pool vegetation establishes along the edges of created pools when dry surface restoration techniques only are used. Pools enhanced plant species richness in natural peatlands. Around created pools, species associated with natural pools were still absent, and non-bog species were present, six years after restoration. On this basis, we emphasise the importance of preserving natural peatlands with pools. In order to restore fully the plant diversity associated with peatlands at harvested sites, it may be necessary to modify pool excavation techniques so that created pools resemble more closely those in natural peatlands. Active introduction of the plant species or communities associated with natural pools may also be needed; candidate species for North America include Andromeda glaucophylla, Cladopodiella fluitans, Carex limosa, Eriophorum virginicum, Rhynchospora alba and Sphagnum cuspidatum.

Grundfoss: Chlorination of Swimming Pools

DEFF Research Database (Denmark)

Hjorth, Poul G.; Hogan, John; Andreassen, Viggo

1998-01-01

Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools.......Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools....

Livestock Grazing as a Driver of Vernal Pool Ecohydrology

Science.gov (United States)

Michaels, J.; McCarten, N. F.

2017-12-01

Vernal pools are seasonal wetlands that host rare plant communities of high conservation priority. Plant community composition is largely driven by pool hydroperiod. A previous study found that vernal pools grazed by livestock had longer hydroperiods compared with pools excluded from grazing for 10 years, and suggests that livestock grazing can be used to protect plant diversity. It is important to assess whether observed differences are due to the grazing or due to water balance variables including upland discharge into or out of the pools since no a priori measurements were made of the hydrology prior to grazing. To address this question, in 2016 we compared 15 pools that have been grazed continuously and 15 pools that have been fenced off for over 40 years at a site in Sacramento County. We paired pools based on abiotic characteristics (size, shape, slope, soil type) to minimize natural variation. We sampled vegetation and water depth using Solinst level loggers. We found that plant diversity and average hydroperiod was significantly higher in the grazed pools. We are currently measuring groundwater connectivity and upland inputs in order to compare the relative strength of livestock grazing as a driver of hydroperiod to these other drivers.

The Role of Nuclear Insurance Pools

International Nuclear Information System (INIS)

Reitsma, S. M. S.

2006-01-01

Since fifty years insurers respond to the need of both governments and the electricity industry to provide financial protection to cover the perils presented by the use of nuclear energy for peaceful purposes. This paper aims at explaining what difficulties had to be solved in order to enable insurers to provide such protection, that as a solution to these difficulties Nuclear Insurance Pools were formed, how such pools operate and what security they provide. Thereby not only a number of universal principles underlying nuclear pool insurance will be explained, but also some differences in the characteristics of such insurance per group of countries. (author)

From wetland specialist to hand-fed generalist: shifts in diet and condition with provisioning for a recently urbanized wading bird.

Science.gov (United States)

Murray, Maureen H; Kidd, Anjelika D; Curry, Shannon E; Hepinstall-Cymerman, Jeffrey; Yabsley, Michael J; Adams, Henry C; Ellison, Taylor; Welch, Catharine N; Hernandez, Sonia M

2018-05-05

Many wildlife species shift their diets to use novel resources in urban areas. The consequences of these shifts are not well known, and consumption of reliable-but low quality-anthropogenic food may present important trade-offs for wildlife health. This may be especially true for carnivorous species such as the American white ibis ( Eudocimus albus ), a nomadic wading bird which has been increasingly observed in urban parks in South Florida, USA. We tested the effects of anthropogenic provisioning on consumer nutrition (i.e. dietary protein), body condition and ectoparasite burdens along an urban gradient using stable isotope analysis, scaled mass index values and GPS transmitter data. Ibises that assimilated more provisioned food were captured at more urban sites, used more urban habitat, had lower mass-length residuals, lower ectoparasite scores, assimilated less δ 15N and had smaller dietary isotopic ellipses. Our results suggest that ibises in urban areas are heavily provisioned with anthropogenic food, which appears to offer a trade-off by providing low-quality, but easily accessible, calories that may not support high mass but may increase time available for anti-parasite behaviours such as preening. Understanding such trade-offs is important for investigating the effects of provisioning on infection risk and the conservation of wildlife in human-modified habitats.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'. © 2018 The Author(s).

Swimming Pool Safety

Science.gov (United States)

... Spread the Word Shop AAP Find a Pediatrician Safety & Prevention Immunizations All Around At Home At Play ... Español Text Size Email Print Share Swimming Pool Safety Page Content ​What is the best way to ...

Nuclear Insurance Pools: World-wide Practice and Prospective

International Nuclear Information System (INIS)

Reitsma, S. M. S.

2000-01-01

The following paper explains why Nuclear Insurance Pools were established, how they operate and what insurance protection they offer to the operations of nuclear installations. It will be shown that the clear interrelationship of the Pool-insurance operations, both on a national and an international level, has resulted in a transparency of each individual Pool-Member's exposure, which enables him to make the highest possible commitment to nuclear risks. Finally, some views will be given as regards the future prospective for the long proven method of pooling this particularly sensitive class of business. (author)

Generation of genome-modified Drosophila cell lines using SwAP.

Science.gov (United States)

Franz, Alexandra; Brunner, Erich; Basler, Konrad

2017-10-02

The ease of generating genetically modified animals and cell lines has been markedly increased by the recent development of the versatile CRISPR/Cas9 tool. However, while the isolation of isogenic cell populations is usually straightforward for mammalian cell lines, the generation of clonal Drosophila cell lines has remained a longstanding challenge, hampered by the difficulty of getting Drosophila cells to grow at low densities. Here, we describe a highly efficient workflow to generate clonal Cas9-engineered Drosophila cell lines using a combination of cell pools, limiting dilution in conditioned medium and PCR with allele-specific primers, enabling the efficient selection of a clonal cell line with a suitable mutation profile. We validate the protocol by documenting the isolation, selection and verification of eight independently Cas9-edited armadillo mutant Drosophila cell lines. Our method provides a powerful and simple workflow that improves the utility of Drosophila cells for genetic studies with CRISPR/Cas9.

The Overestimation Phenomenon in a Skill-Based Gaming Context: The Case of March Madness Pools.

Science.gov (United States)

Kwak, Dae Hee

2016-03-01

Over 100 million people are estimated to take part in the NCAA Men's Basketball Tournament Championship bracket contests. However, relatively little is known about consumer behavior in skill-based gaming situations (e.g., sports betting). In two studies, we investigated the overestimation phenomenon in the "March Madness" context. In Study 1 (N = 81), we found that individuals who were allowed to make their own predictions were significantly more optimistic about their performance than individuals who did not make their own selections. In Study 2 (N = 197), all subjects participated in a mock competitive bracket pool. In line with the illusion of control theory, results showed that higher self-ratings of probability of winning significantly increased maximum willingness to wager but did not improve actual performance. Lastly, perceptions of high probability of winning significantly contributed to consumers' enjoyment and willingness to participate in a bracket pool in the future.

Partition wall structure in spent fuel storage pool and construction method for the partition wall

International Nuclear Information System (INIS)

Izawa, Masaaki

1998-01-01

A partitioning wall for forming cask pits as radiation shielding regions by partitioning inside of a spent fuel storage pool is prepared by covering both surface of a concrete body by shielding metal plates. The metal plate comprises opposed plate units integrated by welding while sandwiching a metal frame as a reinforcing material for the concrete body, the lower end of the units is connected to a floor of a pool by fastening members, and concrete is set while using the metal plate of the units as a frame to form the concrete body. The shielding metal plate has a double walled structure formed by welding a lining plate disposed on the outer surface of the partition wall and a shield plate disposed to the inner side. Then the term for construction can be shortened, and the capacity for storing spent fuels can be increased. (N.H.)

13 CFR 120.1708 - Pool Certificates.

Science.gov (United States)

2010-01-01

... United States. (c) SBA purchase of a Loan Interest. SBA will determine whether to purchase a Loan... reserves the right to purchase a Loan Interest from a Pool at any time. (d) Self-liquidating. A Pool... market conditions and program experience, and will publish any such change in the Federal Register. (h...

ENERGY SAVING AT OPERATION OF OUTDOOR SWIMMING POOLS

Directory of Open Access Journals (Sweden)

V. F. Ivin

2013-09-01

Full Text Available Purpose. Energy saving is a major problem in modern power engineering and various energy-consuming devices. They include outdoor swimming pools. In order to maintain them in working condition, especially in winter period, it takes significant amount of thermal energy. Task of heat loss substantial decrease in open swimming pools is considered in the article (on DNURT example. Methodology. The method of determining the mass and heat loss on the basis of criteria equations of heat and mass transfer theory is used. Findings. Calculations of the actual DNURT pool heat loss for different seasons, as for natural convection both for air forced motion above the free water surface are performed. It is shown that for the adiabatic evaporation conditions of water from the pool in winter during blow-off with wind the heat loss can be up to 2 kW/m2 on surface. To reduce these losses it is offered to cover water surface in a pool with a special material with low thermal conductivity on the basis of porous polyethylene during the time when the pool is not used for other purposes. It is shown that the implementation of these standards will reduce the actual heat loss, at least 5-6 times. Originality. The solution of important environmental and energy problem thanks to reducing heat losses by the pool in different times of a year and correspondingly lower emissions of power generating enterprises. Practical value. It is shown that the coating surface of the pool with poorly heat-conducting and easy to install coating will let, at a minimum, to reduce the actual heat loss on 5-6 times and reduce the emissions of power plants generating energy for pool heating.

Numerical analysis of weld pool oscillation in laser welding

Energy Technology Data Exchange (ETDEWEB)

Cho, Jung Ho [Chungbuk National University, Cheongju (Korea, Republic of); Farson, Dave F [The Ohio State University, Columbus (United States); Hollis, Kendall; Milewski, John O. [Los Alamos National Laboratory, Los Alamos (United States)

2015-04-15

Volume of fluid (VOF) numerical simulation was used to investigate melt flow and volumetric oscillation of conduction-mode pulsed laser weld pools. The result is compared to high speed video stream of titanium laser spot welding experiment. The total simulation time is 10ms with the first 5 ms being heating and melting under constant laser irradiation and the remaining 5 ms corresponding to resolidification of the weld pool. During the melting process, the liquid pool did not exhibit periodic oscillation but was continually depressed by the evaporation recoil pressure. After the laser pulse, the weld pool was excited into volumetric oscillation by the release of pressure on its surface and oscillation of the weld pool surface was analyzed. The simulation model suggested adjusting thermal diffusivity to match cooling rate and puddle diameter during solidification which is distinguishable from previous weld pool simulation. The frequency continuously increased from several thousand cycles per second to tens of thousands of cycles per second as the weld pool solidified and its diameter decreased. The result is the first trial of investigation of small weld pool oscillation in laser welding although there have been several reports about arc welding.

CDC Study Finds Fecal Contamination in Pools

Science.gov (United States)

... Communication (404) 639-3286 CDC study finds fecal contamination in pools A study of public pools done ... The E. coli is a marker for fecal contamination. Finding a high percentage of E. coli-positive ...

Sediment transport through self-adjusting, bedrock-walled waterfall plunge pools

Science.gov (United States)

Scheingross, Joel S.; Lamb, Michael P.

2016-05-01

Many waterfalls have deep plunge pools that are often partially or fully filled with sediment. Sediment fill may control plunge-pool bedrock erosion rates, partially determine habitat availability for aquatic organisms, and affect sediment routing and debris flow initiation. Currently, there exists no mechanistic model to describe sediment transport through waterfall plunge pools. Here we develop an analytical model to predict steady-state plunge-pool depth and sediment-transport capacity by combining existing jet theory with sediment transport mechanics. Our model predicts plunge-pool sediment-transport capacity increases with increasing river discharge, flow velocity, and waterfall drop height and decreases with increasing plunge-pool depth, radius, and grain size. We tested the model using flume experiments under varying waterfall and plunge-pool geometries, flow hydraulics, and sediment size. The model and experiments show that through morphodynamic feedbacks, plunge pools aggrade to reach shallower equilibrium pool depths in response to increases in imposed sediment supply. Our theory for steady-state pool depth matches the experiments with an R2 value of 0.8, with discrepancies likely due to model simplifications of the hydraulics and sediment transport. Analysis of 75 waterfalls suggests that the water depths in natural plunge pools are strongly influenced by upstream sediment supply, and our model provides a mass-conserving framework to predict sediment and water storage in waterfall plunge pools for sediment routing, habitat assessment, and bedrock erosion modeling.

Pool scrubbing and hydrodynamic experiments on jet injection regime

International Nuclear Information System (INIS)

Peyres, V.; Espigares, M.M.; Polo, J.; Escudero, M.J.; Herranz, L.E.; Lopez-Jimenez, J.

1995-01-01

Plant analyses have shown that pool scrubbing can play an important role in source term during PWR risk dominant sequences. An examination ofboundary conditions governing fission products and aerosols transport through aqueous beds revealed that most of radioactivity is discharged into the pool under jet injection regime. This fact and the lack of experimental data under such conditions pointed the need of setting out an experimental programme which provided reliable experimental data to validate code models. In this report the major results of a pool scrubbing experimental programme carried out in PECA facility are presented. One of the major findings was that a remarkable fraction of particle absorption was not a function of the residence time of bubbles rising through the pool. Such a contribution was assumed to be associated to aerosol removal mechanisms acting at the pool entrance. As a consequence, a hydrodynamic experimental plan was launched to examine the gas behaviour during the initial stages in the pool. Size and shape of gas nuclei the pool were measured and fitted to a long normal distribution. Particularly, size was found to be quite sensitive to inletgas flow and at minor extent to gas composition and pool temperature. SPARC90 and BUSCA-AUG92 were used to simulate the retention tests. Whereas SPARC90 showed a pretty good agreement with experimental data, BUSCA-AUG92 results were far away from measurements in all the cases. SPARC90consistency apparently pointed out the important role of fission products and aerosols retention at the injection zone; nonetheless, a peer examination of pool scrubbing phenomenology at the pool entrance should be carried out to test both hydrodynamic and removal models. Hence, one of the major highlights drawn from this work was the need of further research under representative severe accident conditions (i.e., saturated pools, jet injection regimes, etc.), as well as separate effect tests to validate, improve and

Pool scrubbing and hydrodynamic experiment on jet injection regime

Energy Technology Data Exchange (ETDEWEB)

Peyres, V.; Espigares, M.M.; Polo, J.; Escudero, M.J.; Herranz, L.E.; Lopez, J.

1995-07-01

Plant analyses nave shown that pool scrubbing can play an important role in source term during PWR risk dominant sequences. An examination of boundary conditions governing fission products and aerosols transport through aqueous beds revealed that most of radioactivity is discharged into the pool under jet injection regime. This fact and the lack of experimental data under such conditions pointed the need of setting out an experimental programme which provided reliable experimental data to validate code models. In this report the major results of a pool scrubbing experimental programme carried out in PECA facility are presented. One of the major findings was that a remarkable fraction of particle absorption was not a function of the residence time of bubbles rising through the pool. Such a contribution was assumed to be associated to aerosol removal mechanism acting at the pool entrance. As a consequence. a hydrodynamic experimental plan was launched to examine the gas behaviour during the initial stages in the pool. Size and shape of gas nuclei in the pool were measured and fitted to a lognormal distribution. Particularly, size was found to be quite sensitive to inlet gas flow and at minor extent to gas composition and pool temperature. SPARC90 and BUSCA-AUG92 were used to simulate the retention tests. Whereas SPARC90 showed a pretty good agreement with experimental data, BUSCA-AUG92 results were far away from measurements in all the cases. SPARC90 consistency apparently pointed out the important role of fission products and aerosols retention at the injection zone; nonetheless, a peer examination of pool scrubbing phenomenology at the pool entrance should be carried out to test both hydrodynamic and removal models. Hence, one of the major high lights drawn from this work was the need of further research under representative severe accident conditions (i.e., saturated pools, jet injection regimes, etc.), as well as separate effect tests to validate, improve and

Pool scrubbing and hydrodynamic experiment on jet injection regime

International Nuclear Information System (INIS)

Peyres, V.; Espigares, M.M.; Polo, J.; Escudero, M.J.; Herranz, L.E.; Lopez, J.

1995-01-01

Plant analyses nave shown that pool scrubbing can play an important role in source term during PWR risk dominant sequences. An examination of boundary conditions governing fission products and aerosols transport through aqueous beds revealed that most of radioactivity is discharged into the pool under jet injection regime. This fact and the lack of experimental data under such conditions pointed the need of setting out an experimental programme which provided reliable experimental data to validate code models. In this report the major results of a pool scrubbing experimental programme carried out in PECA facility are presented. One of the major findings was that a remarkable fraction of particle absorption was not a function of the residence time of bubbles rising through the pool. Such a contribution was assumed to be associated to aerosol removal mechanism acting at the pool entrance. As a consequence. a hydrodynamic experimental plan was launched to examine the gas behaviour during the initial stages in the pool. Size and shape of gas nuclei in the pool were measured and fitted to a lognormal distribution. Particularly, size was found to be quite sensitive to inlet gas flow and at minor extent to gas composition and pool temperature. SPARC90 and BUSCA-AUG92 were used to simulate the retention tests. Whereas SPARC90 showed a pretty good agreement with experimental data, BUSCA-AUG92 results were far away from measurements in all the cases. SPARC90 consistency apparently pointed out the important role of fission products and aerosols retention at the injection zone; nonetheless, a peer examination of pool scrubbing phenomenology at the pool entrance should be carried out to test both hydrodynamic and removal models. Hence, one of the major high lights drawn from this work was the need of further research under representative severe accident conditions (i.e., saturated pools, jet injection regimes, etc.), as well as separate effect tests to validate, improve and

Turbulence model for melt pool natural convection heat transfer

International Nuclear Information System (INIS)

Kelkar, K.M.; Patankar, S.V.

1994-01-01

Under severe reactor accident scenarios, pools of molten core material may form in the reactor core or in the hemispherically shaped lower plenum of the reactor vessel. Such molten pools are internally heated due to the radioactive decay heat that gives rise to buoyant flows in the molten pool. The flow in such pools is strongly influenced by the turbulent mixing because the expected Rayleigh numbers under accidents scenarios are very high. The variation of the local heat flux over the boundaries of the molten pools are important in determining the subsequent melt progression behavior. This study reports results of an ongoing effort towards providing a well validated mathematical model for the prediction of buoyant flow and heat transfer in internally heated pool under conditions expected in severe accident scenarios

Controls on Filling and Evacuation of Sediment in Waterfall Plunge Pools

Science.gov (United States)

Scheingross, J. S.; Lamb, M. P.

2014-12-01

Many waterfalls are characterized by the presence of deep plunge pools that experience periods of sediment fill and evacuation. These cycles of sediment fill are a first order control on the relative magnitude of lateral versus vertical erosion at the base of waterfalls, as vertical incision requires cover-free plunge pools to expose the bedrock floor, while lateral erosion can occur when pools are partially filled and plunge-pool walls are exposed. Currently, there exists no mechanistic model describing sediment transport through waterfall plunge pools, limiting our ability to predict waterfall retreat. To address this knowledge gap, we performed detailed laboratory experiments measuring plunge-pool sediment transport capacity (Qsc_pool) under varying waterfall and plunge-pool geometries, flow hydraulics, and sediment size. Our experimental plunge-pool sediment transport capacity measurements match well with a mechanistic model we developed which combines existing waterfall jet theory with a modified Rouse profile to predict sediment transport capacity as a function of water discharge and suspended sediment concentration at the plunge-pool lip. Comparing the transport capacity of plunge pools to lower gradient portions of rivers (Qsc_river) shows that, for transport limited conditions, plunge pools fill with sediment under modest water discharges when Qsc_river > Qsc_pool, and empty to bedrock under high discharges when Qsc_pool > Qsc_river. These results are consistent with field observations of sand-filled plunge pools with downstream boulder rims, implying filling and excavation of plunge pools over single-storm timescales. Thus, partial filling of waterfall plunge pools may provide a mechanism to promote lateral undercutting and retreat of waterfalls in homogeneous rock in which plunge-pool vertical incision occurs during brief large floods that expose bedrock, whereas lateral erosion may prevail during smaller events.

(Microbiological studies of small hot-bath-pools and hot-whirl-pools (author's transl))

Energy Technology Data Exchange (ETDEWEB)

Exner, M; Havenith, N

1981-01-01

Hot small bathing pools and hot whirl-pools have the following characteristics: small watervolume, thick squeeze of swimmers, high water temperature (37-40 degrees C) and small dimension of filters. By this, the quality of bathing-water is influenced detrimentally. To elaborate the hygienic problems, bathing-water samples were taken before, during and after the visiting-hours and were tested for facultative-pathogenic microorganisms. During this investigation E. coli was isolated in 25 degrees, Coliforms and Proteus species in 37.3%, P. aeruginosa in 36%, S. aureus in 26.3%, Enterococci in 42.3 %, Candida albicans in 3.6% and yeast totally in 8.3%.

Environmental controls of C, N and P biogeochemistry in peatland pools.

Science.gov (United States)

Arsenault, Julien; Talbot, Julie; Moore, Tim R

2018-08-01

Pools are common in northern peatlands but studies have seldom focused on their nutrient biogeochemistry, especially in relation to their morphological characteristics and through seasons. We determined the environmental characteristics controlling carbon (C), nitrogen (N) and phosphorus (P) biogeochemistry in pools and assessed their evolution over the course of the 2016 growing season in a subboreal ombrotrophic peatland of eastern Canada. We showed that water chemistry variations in 62 pools were significantly explained by depth (81.9%) and the surrounding vegetation type (14.8%), but not by pool area or shape. Shallow pools had larger dissolved organic carbon (DOC) and total nitrogen (TN) concentrations and lower pH than deep pools, while pools surrounded by coniferous trees had more recalcitrant DOC than pools where vegetation was dominated by mosses. The influence of depth on pool biogeochemistry was confirmed by the seasonal survey of pools of different sizes with 47.1% of the variation in pool water chemistry over time significantly explained. Of this, 67.3% was explained by the interaction between time and pool size and 32.7% by pool size alone. P concentrations were small in all pools all summer long and combined with high N:P ratios, are indicative of P-limitation. Our results show that pool biogeochemistry is influenced by internal processes and highlight the spatial and temporal heterogeneity of nutrient biogeochemistry in ombrotrophic peatlands. Copyright © 2018 Elsevier B.V. All rights reserved.

Off-Line High-pH Reversed-Phase Fractionation for In-Depth Phosphoproteomics

DEFF Research Database (Denmark)

Batth, Tanveer S; Francavilla, Chiara; Olsen, Jesper V

2014-01-01

thousands of phosphorylation sites. However, in-depth phosphoproteomics often require off-line enrichment and fractionation techniques. In this study, we provide a detailed analysis of the physicochemical characteristics of phosphopeptides, which have been fractionated by off-line high-pH chromatography (Hp...... phosphorylated peptides over that with SCX. Further optimizations in the pooling and concatenation strategy increased the total number of multiphosphorylated peptides detected after HpH fractionation. In conclusion, we provide a basic framework and resource for performing in-depth phosphoproteome studies...

Rapid protein production from stable CHO cell pools using plasmid vector and the cumate gene-switch.

Science.gov (United States)

Poulain, Adeline; Perret, Sylvie; Malenfant, Félix; Mullick, Alaka; Massie, Bernard; Durocher, Yves

2017-08-10

To rapidly produce large amounts of recombinant proteins, the generation of stable Chinese Hamster Ovary (CHO) cell pools represents a useful alternative to large-scale transient gene expression (TGE). We have developed a cell line (CHO BRI/rcTA ) allowing the inducible expression of recombinant proteins, based on the cumate gene switch. After the identification of optimal plasmid DNA topology (supercoiled vs linearized plasmid) for PEIpro™ mediated transfection and of optimal conditions for methionine sulfoximine (MSX) selection, we were able to generate CHO BRI/rcTA pools producing high levels of recombinant proteins. Volumetric productivities of up to 900mg/L were reproducibly achieved for a Fc fusion protein and up to 350mg/L for an antibody after 14days post-induction in non-optimized fed-batch cultures. In addition, we show that CHO pool volumetric productivities are not affected by a freeze-thaw cycle or following maintenance in culture for over one month in the presence of MSX. Finally, we demonstrate that volumetric protein production with the CR5 cumate-inducible promoter is three- to four-fold higher than with the human CMV or hybrid EF1α-HTLV constitutive promoters. These results suggest that the cumate-inducible CHO BRI/rcTA stable pool platform is a powerful and robust system for the rapid production of gram amounts of recombinant proteins. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Reserve growth in oil pools of Alberta : model and forecast

Energy Technology Data Exchange (ETDEWEB)

Verma, M.; Cook, T. [United States Geological Survey, Denver, CO (United States). Central Region

2010-09-15

This paper presented a reserve growth study that was conducted on oil pools in Alberta, Canada. Historical oil reserve data were evaluated to assess the potential for future reserve growth in both pools and fields, and reserve growth models and functions were developed to better forecast hydrocarbon volumes. The study also considered the sensitivity of reserve growth to such factors as pool size, porosity, and oil gravity. From 1960 to 2005, the reported known recoverable oil in Alberta, excluding the Athabasca oil sands and including only pools with adequate data, increased from 4.2 to 13.9 billion barrels of oil (BBO). New discoveries contributed 3.7 BBO and reserve growth added 6 BBO. Most reserve growth occurred in pools with more than 125,000 barrels of oil. Light-oil pools account for most of the total known oil volume and consequently showed the lowest growth. Pools with greater than 30 percent porosity grew more than pools with lower porosity reservoirs. Oil field growth was found to be almost twice that of pool growth, possibly because the analysis evaluated fields with two or more pools discovered in different years. The growth in oil volumes in Alberta pools is projected to be about 454 million barrels of oil in the period from 2006 to 2010. Over a 25-year period, the cumulative reserve growth in Alberta oil pools was substantially lower than other major petroleum-producing regions, but the growth at the field level compares well. 8 refs., 2 tabs., 9 figs.

Numerical modelling of methanol liquid pool fires

Science.gov (United States)

Prasad, Kuldeep; Li, Chiping; Kailasanath, K.; Ndubizu, Chuka; Ananth, Ramagopal; Tatem, P. A.

1999-12-01

The focus of this paper is on numerical modelling of methanol liquid pool fires. A mathematical model is first developed to describe the evaporation and burning of a two-dimensional or axisymmetric pool containing pure liquid methanol. Then, the complete set of unsteady, compressible Navier-Stokes equations for reactive flows are solved in the gas phase to describe the convection of the fuel gases away from the pool surface, diffusion of the gases into the surrounding air and the oxidation of the fuel into product species. Heat transfer into the liquid pool and the metal container through conduction, convection and radiation are modelled by solving a modified form of the energy equation. Clausius-Clapeyron relationships are invoked to model the evaporation rate of a two-dimensional pool of pure liquid methanol. The governing equations along with appropriate boundary and interface conditions are solved using the flux-corrected transport algorithm. Numerical results exhibit a flame structure that compares well with experimental observations. Temperature profiles and burning rates were found to compare favourably with experimental data from single- and three-compartment laboratory burners. The model predicts a puffing frequency of approximately 12 Hz for a 1 cm diameter methanol pool in the absence of any air co-flow. It is also observed that increasing the air co-flow velocity helps in stabilizing the diffusion flame, by pushing the vortical structures away from the flame region.

Robotic cleaning of a spent fuel pool

International Nuclear Information System (INIS)

Roman, H.T.; Marian, F.A.; Silverman, E.B.; Barkley, V.P.

1987-01-01

Spent fuel pools at nuclear power plants are not cleaned routinely, other than by purifying the water that they contain. Yet, debris can collect on the bottom of a pool and should be removed prior to fuel transfer. At Public Service Electric and Gas Company's Hope Creek Nuclear Power Plant, a submersible mobile robot - ARD Corporation's SCAVENGER - was used to clean the bottom of the spent fuel pool prior to initial fuel loading. The robotic device was operated remotely (as opposed to autonomously) with a simple forward/reverse control, and it cleaned 70-80% of the pool bottom. This paper reports that a simple cost-benefit analysis shows that the robotic device would be less expensive, on a per mission basis, than other cleaning alternatives, especially if it were used for other similar cleaning operations throughout the plant

Longevity of Wood-Forced Pools in an Old-Growth Forest

Science.gov (United States)

Buffington, J. M.; Woodsmith, R. D.; Johnson, A. C.

2009-12-01

Wood debris plays an important role in scouring pools in forest channels and providing resultant habitat for aquatic organisms. We investigated the longevity of such pools in a gravel-bed river flowing through old-growth forest in southeastern Alaska by aging trees and “bear’s bread” fungi (Ganoderma applanatum, Fomitopsis pinicola) growing on pool-forming wood debris. Ages were determined by counting annual growth rings from cores and cross sections of trees and fungi growing on the wood debris. These ages are minimum values because they do not account for lag time between debris recruitment and seedling/spore establishment on the debris, nor do they account for flood scour that may periodically reset tree and fungi growth on the debris. The study stream has a gradient of about 1%, bankfull width and depth of 13.3 and 0.78 m, respectively, median grain size of 18 mm, a high wood loading (0.8 pieces/m), and a correspondingly low pool spacing (0.3 bankfull widths/pool), with 81% of the pools forced by wood debris. The size of wood debris in the study stream is large relative to the channel (average log length of 7.6 m and diameter of 0.35 m), rendering most debris immobile. Eighty-one pool-forming pieces of wood were dated over 1.2 km of stream length, with 28% of these pieces causing scour of more than one pool. In all, 122 wood-forced pools were dated, accounting for 38% of all pools at the site and 47% of the wood-forced pools. Fifty-three percent of the wood-forced pools lacked datable wood because these pieces either: were newly recruited; had been scoured by floods; or were contained below the active channel elevation, prohibiting vegetation establishment on the wood debris (the most common cause). The debris age distribution declined exponentially from 2 to 113 yrs., with a median value of 18 yrs. Similar exponential residence time distributions have been reported in other studies, but our analysis focused specifically on the ages of pool-forming wood

Controlling pool depth during VAR of Alloy 718

Science.gov (United States)

Lopez, F.; Beaman, J.; Williamson, R.; Evans, D.

2016-07-01

A longtime goal of superalloy producers has been to control the geometry of the liquid pool in solidifying ingots. Accurate pool depth control at appropriate values is expected to result in ingots free of segregation defects. This article describes an industrial VAR experiment in which a 430mm (17 in) diameter Alloy 718 electrode was melted into a 510mm (20 in) ingot. In the experiment, the depth of the liquid pool at the mid-radius was controlled to three different set-points: 137 mm (nominal), 193 mm (deep) and 118 mm (shallow). At each level, the pool depth was marked by a power cutback of several minutes. The ingot was sectioned and longitudinal slices were cut out. Analysis of the photographed ingot revealed that accurate control was obtained for both the nominal and deep pool cases, while the third one was not conclusive.

Estimated environmental radionuclide transfer and deposition into outdoor swimming pools

International Nuclear Information System (INIS)

Tagami, Kazumi; Nagata, Izumi; Sueki, Keisuke

2014-01-01

In 2011, a large radioactive discharge occurred at the Fukushima Daiichi nuclear power plant. This plant is located within a climatically temperate region where outdoor swimming pools are popular. Although it is relatively easy to decontaminate pools by refilling them with fresh water, it is difficult to maintain safe conditions given highly contaminated diurnal dust falls from the surrounding contaminated ground. Our objectives in this paper were to conduct daily radioactivity measurements, to determine the quantity of radioactive contaminants from the surrounding environment that invade outdoor pools, and to investigate the efficacy of traditional pool cleaners in removing radioactive contaminants. The depositions in the paper filterable particulates ranged from 0 to 62,5 Bq/m 2 /day, with the highest levels found in the southern Tohoku District containing Fukushima Prefecture and in the Kanto District containing Tokyo Metro. They were approximately correlated with the ground contamination. Traditional pool cleaners eliminated 99% of contaminants at the bottom of the pool, reducing the concentration to 41 Bq/m 2 after cleaning. Authors recommended the deposition or the blown radionuclides into outdoor swimming pools must be considered into pool regulations when the environments exactly polluted with radionuclides. - Highlights: • Deposition into outdoor swimming pool in a habitable areas estimated 72 Bq/m 2 /day. • More than 500 Bq/m 2 /day deposition will exceed our national guideline (10 Bq/l) of swimming pool. • Vacuum pool cleaner eliminates 99% radionuclides deposition

Macroinvertebrate community assembly in pools created during peatland restoration

Energy Technology Data Exchange (ETDEWEB)

Brown, Lee E., E-mail: l.brown@leeds.ac.uk; Ramchunder, Sorain J.; Beadle, Jeannie M.; Holden, Joseph

2016-11-01

Many degraded ecosystems are subject to restoration attempts, providing new opportunities to unravel the processes of ecological community assembly. Restoration of previously drained northern peatlands, primarily to promote peat and carbon accumulation, has created hundreds of thousands of new open water pools. We assessed the potential benefits of this wetland restoration for aquatic biodiversity, and how communities reassemble, by comparing pool ecosystems in regions of the UK Pennines on intact (never drained) versus restored (blocked drainage-ditches) peatland. We also evaluated the conceptual idea that comparing reference ecosystems in terms of their compositional similarity to null assemblages (and thus the relative importance of stochastic versus deterministic assembly) can guide evaluations of restoration success better than analyses of community composition or diversity. Community composition data highlighted some differences in the macroinvertebrate composition of restored pools compared to undisturbed peatland pools, which could be used to suggest that alternative end-points to restoration were influenced by stochastic processes. However, widely used diversity metrics indicated no differences between undisturbed and restored pools. Novel evaluations of restoration using null models confirmed the similarity of deterministic assembly processes from the national species pool across all pools. Stochastic elements were important drivers of between-pool differences at the regional-scale but the scale of these effects was also similar across most of the pools studied. The amalgamation of assembly theory into ecosystem restoration monitoring allows us to conclude with more certainty that restoration has been successful from an ecological perspective in these systems. Evaluation of these UK findings compared to those from peatlands across Europe and North America further suggests that restoring peatland pools delivers significant benefits for aquatic fauna by

Macroinvertebrate community assembly in pools created during peatland restoration

International Nuclear Information System (INIS)

Brown, Lee E.; Ramchunder, Sorain J.; Beadle, Jeannie M.; Holden, Joseph

2016-01-01

Many degraded ecosystems are subject to restoration attempts, providing new opportunities to unravel the processes of ecological community assembly. Restoration of previously drained northern peatlands, primarily to promote peat and carbon accumulation, has created hundreds of thousands of new open water pools. We assessed the potential benefits of this wetland restoration for aquatic biodiversity, and how communities reassemble, by comparing pool ecosystems in regions of the UK Pennines on intact (never drained) versus restored (blocked drainage-ditches) peatland. We also evaluated the conceptual idea that comparing reference ecosystems in terms of their compositional similarity to null assemblages (and thus the relative importance of stochastic versus deterministic assembly) can guide evaluations of restoration success better than analyses of community composition or diversity. Community composition data highlighted some differences in the macroinvertebrate composition of restored pools compared to undisturbed peatland pools, which could be used to suggest that alternative end-points to restoration were influenced by stochastic processes. However, widely used diversity metrics indicated no differences between undisturbed and restored pools. Novel evaluations of restoration using null models confirmed the similarity of deterministic assembly processes from the national species pool across all pools. Stochastic elements were important drivers of between-pool differences at the regional-scale but the scale of these effects was also similar across most of the pools studied. The amalgamation of assembly theory into ecosystem restoration monitoring allows us to conclude with more certainty that restoration has been successful from an ecological perspective in these systems. Evaluation of these UK findings compared to those from peatlands across Europe and North America further suggests that restoring peatland pools delivers significant benefits for aquatic fauna by

Macroinvertebrate community assembly in pools created during peatland restoration.

Science.gov (United States)

Brown, Lee E; Ramchunder, Sorain J; Beadle, Jeannie M; Holden, Joseph

2016-11-01

Many degraded ecosystems are subject to restoration attempts, providing new opportunities to unravel the processes of ecological community assembly. Restoration of previously drained northern peatlands, primarily to promote peat and carbon accumulation, has created hundreds of thousands of new open water pools. We assessed the potential benefits of this wetland restoration for aquatic biodiversity, and how communities reassemble, by comparing pool ecosystems in regions of the UK Pennines on intact (never drained) versus restored (blocked drainage-ditches) peatland. We also evaluated the conceptual idea that comparing reference ecosystems in terms of their compositional similarity to null assemblages (and thus the relative importance of stochastic versus deterministic assembly) can guide evaluations of restoration success better than analyses of community composition or diversity. Community composition data highlighted some differences in the macroinvertebrate composition of restored pools compared to undisturbed peatland pools, which could be used to suggest that alternative end-points to restoration were influenced by stochastic processes. However, widely used diversity metrics indicated no differences between undisturbed and restored pools. Novel evaluations of restoration using null models confirmed the similarity of deterministic assembly processes from the national species pool across all pools. Stochastic elements were important drivers of between-pool differences at the regional-scale but the scale of these effects was also similar across most of the pools studied. The amalgamation of assembly theory into ecosystem restoration monitoring allows us to conclude with more certainty that restoration has been successful from an ecological perspective in these systems. Evaluation of these UK findings compared to those from peatlands across Europe and North America further suggests that restoring peatland pools delivers significant benefits for aquatic fauna by

Sharing as risk pooling in a social dilemma experiment

Directory of Open Access Journals (Sweden)

Todd L. Cherry

2015-03-01

Full Text Available In rural economies with missing or incomplete markets, idiosyncratic risk is frequently pooled through informal networks. Idiosyncratic shocks, however, are not limited to private goods but can also restrict an individual from partaking in or benefiting from a collective activity. In these situations, a group must decide whether to provide insurance to the affected member. We describe results of a laboratory experiment designed to test whether a simple sharing institution can sustain risk pooling in a social dilemma with idiosyncratic risk. We tested whether risk could be pooled without a commitment device and, separately, whether effective risk pooling induced greater cooperation in the social dilemma. We found that even in the absence of a commitment device or reputational considerations, subjects voluntarily pooled risk, thereby reducing variance in individual earnings. In spite of effective risk pooling, however, cooperation in the social dilemma was unaffected.

Nuclear Insurance Pools: Worldwide Practice and Development

International Nuclear Information System (INIS)

Reitsma, S. M. S.

1998-01-01

The development of nuclear installations to produce electricity led to the establishment of Nuclear Insurance Pools and the introduction of international Conventions on Third Party Liability. Nuclear Pools offer both Third Party Liability insurance, reflecting the Conventions' principles, and other insurance products. They are market-wide, providing a facility for participation by insurers who could not otherwise write the insurance for the particularly sensitive nuclear risk. All acceptances are for the net retention of each Member without recourse to individual reinsurance protection. Common account reinsurance is arranged with other Nuclear Pools all over the world. Thus, a transparency is created, which ensures the highest degree of reinsurance security and imposes a known finite limit to each participating insurer's commitment. Therefore, Pool-members are prepared to make a greater commitment to nuclear risks than would be case where they felt uncertain as regards their total exposure following a significant loss. (author)

Opportunities and challenges when pooling milk samples using ELISA

DEFF Research Database (Denmark)

Græsbøll, Kaare; Andresen, Lars Ole; Hisham Beshara Halasa, Tariq

2017-01-01

-positive samples by pooling. To illustrate this, the sensitivity of antibody ELISA on pooled samples of bovine milk for Salmonella Dublin, Mycobacterium avium spp. paratuberculosis, and bovine virus diarrhea was tested. For these milk assays, the analytical sensitivity decreased rapidly with increasing pool sizes...

Microscopic bubble behaviour in suppression pool during wetwell venting

Science.gov (United States)

Zablackaite, G.; Nagasaka, H.; Kikura, H.

2017-10-01

During a severe accident PCV failure should be avoided and fission products inside PCV should be confined as much as possible. In order to minimize FPs release, Wetwell venting is conducted by releasing steam-non-condensable gas mixture carrying FPs from the Drywell to Suppression Pool. Steam is condensed by subcooled water in the pool, and most of FPs are retained into water. The removal of FP in the water pool is referred to as “Pool Scrubbing effect”. Hydrodynamic parameters of bubbles have impact on pool scrubbing effect. However, there is only few data available to evaluate quantitatively the bubble behaviour under depressurization and/or thermal stratification conditions. Series of experiments were conducted to evaluate the influence of temperature distribution, non-condensable gas content and pressure in the Wetwell on bubble behaviour. Bubbles were visualized using High Speed Camera and adopting shadowgraphy technique. Applying Particle Tracking Velocimetry, bubble velocity and size distribution were obtained from recorded images. Experimental results show that with increasing suppression pool temperature, bubbles reaching the pool surface decreased in size and traveling velocity became slower. In pressurized wetwell, bubble behaviour was similar to that in the heated up suppression pool case, although bubble parameters were similar to the low temperature case. Higher air content induced water surface movement and bubbles were smaller due to break up.

3D finite element simulation of TIG weld pool

Science.gov (United States)

Kong, X.; Asserin, O.; Gounand, S.; Gilles, P.; Bergheau, J. M.; Medale, M.

2012-07-01

The aim of this paper is to propose a three-dimensional weld pool model for the moving gas tungsten arc welding (GTAW) process, in order to understand the main factors that limit the weld quality and improve the productivity, especially with respect to the welding speed. Simulation is a very powerful tool to help in understanding the physical phenomena in the weld process. A 3D finite element model of heat and fluid flow in weld pool considering free surface of the pool and traveling speed has been developed for the GTAW process. Cast3M software is used to compute all the governing equations. The free surface of the weld pool is calculated by minimizing the total surface energy. The combined effects of surface tension gradient, buoyancy force, arc pressure, arc drag force to drive the fluid flow is included in our model. The deformation of the weld pool surface and the welding speed affect fluid flow, heat flow and thus temperature gradients and molten pool dimensions. Welding trials study is presented to compare our numerical results with macrograph of the molten pool.

48 CFR 28.304 - Risk-pooling arrangements.

Science.gov (United States)

2010-10-01

... CONTRACTING REQUIREMENTS BONDS AND INSURANCE Insurance 28.304 Risk-pooling arrangements. Agencies may establish risk-pooling arrangements. These arrangements are designed to use the services of the insurance industry for safety engineering and the handling of claims at minimum cost to the Government. The agency...

Indoor swimming pools. Humidity caused problems and suggested solutions

Energy Technology Data Exchange (ETDEWEB)

1989-01-01

Reports have been received from across Canada on premature deterioration and other problems of indoor swimming pool buildings. This technical paper has been prepared to assist pool managers to solve these problems, which typically include leaking roofs, condensation on inside walls, peeling paint, efflorescence, rusting of metal elements, deterioration of concrete block structures, and high costs for pool heating. An effective insulation and vapor barrier system for a swimming pool roof is described, and the high relative humidity of the typical pool building is discussed as the primary cause of most problems. Proper sealing to cut down air infiltration is recommended, along with proper maintenance and painting. High energy costs are often due to low insulation values and to excessive ventilation used for decreasing the humidity. By using dehumidifiers capable of heat recovery, and by placing an insulating blanket on the pool after operating hours, it is shown that substantial cost savings are possible. 10 figs.

Detection of 41Ar diffusion from a TRIGA pool

International Nuclear Information System (INIS)

Foss, Scott; Nelson, George

1990-01-01

Argon-41 levels in very low concentrations in the reactor room air can be inferred from the rate of escape from the pool water surface. The rate of Argon-41 diffusion from pool water to room air was determined by the measurement of the activity buildup in containers of air in contact with the pool surface. The Argon-41 concentration in each container was measured by gamma-ray spectrometry with a calibrated GeLi detector. At 100 KW power with the water temperature at 10 deg. Celsius the total release of Argon-41 was determined to be 3.5e10±15% atoms for 80 minutes of operation. The corresponding activity released from the pool was 98.6 microcuries, while the total activity produced in the pool was 4900 microcuries. The diffusion coefficient of Argon-41 from the pool water surface to the air at this temperature was measured to be 3.14e-14 sec-cm 2 . (author)

Expanding the live kidney donor pool: ethical considerations regarding altruistic donors, paired and pooled programs.

Science.gov (United States)

Patel, Shaneel Rajendra; Chadha, Priyanka; Papalois, Vassilios

2011-06-01

In renal transplant, there is a well-known deficiency in organ supply relative to demand. Live donation provides superior results when compared with deceased donation including a better rate of graft success and fewer immunologic complications. This deficiency in organs leads to significant morbidity and mortality rates. Alternative avenues have been extensively explored that may expand the live donor pool. They include altruistic donation as well as paired and pooled exchange programs. Altruistic donation is a truly selfless act from a donor unknown to the recipient. Kidney paired donation involves 2 incompatible donor-recipient pairs swapping donors to produce compatibility. Pooled donation involves at least 2 pairs, and can take the form of domino chains in which altruistic input sets up a chain of transplants, in which each recipient's incompatible donor makes a donation for the next recipient. Despite application of these various methods, there lie extensive ethical issues surrounding them. Misconceptions frequently occur; for instance, the perceived benefit that donating an organ to a loved one is greater for a related donor than for an altruistic one. Additionally, it is frequently believed that immunologic incompatibility offers coerced donors liberation from surgery, and that overcoming these barriers by introducing exchange programs provides vulnerable donors less protection. This article explores these and other complex ethical issues surrounding the various methods of expanding the donor pool. The authors offer opinions that challenge the ethical issues and attempt to overcome those views that hinder progress in the field.

LNG pool fire simulation for domino effect analysis

International Nuclear Information System (INIS)

Masum Jujuly, Muhammad; Rahman, Aziz; Ahmed, Salim; Khan, Faisal

2015-01-01

A three-dimensional computational fluid dynamics (CFD) simulation of liquefied natural gas (LNG) pool fire has been performed using ANSYS CFX-14. The CFD model solves the fundamental governing equations of fluid dynamics, namely, the continuity, momentum and energy equations. Several built-in sub-models are used to capture the characteristics of pool fire. The Reynolds-averaged Navier–Stokes (RANS) equation for turbulence and the eddy-dissipation model for non-premixed combustion are used. For thermal radiation, the Monte Carlo (MC) radiation model is used with the Magnussen soot model. The CFD results are compared with a set of experimental data for validation; the results are consistent with experimental data. CFD results show that the wind speed has significant contribution on the behavior of pool fire and its domino effects. The radiation contours are also obtained from CFD post processing, which can be applied for risk analysis. The outcome of this study will be helpful for better understanding of the domino effects of pool fire in complex geometrical settings of process industries. - Highlights: • Simulation of pool fire using computational fluid dynamics (CFD) model. • Integration of CFD based pool fire model with domino effect. • Application of the integrated CFD based domino effect analysis

A method of measuring a molten metal liquid pool volume

Science.gov (United States)

Garcia, G.V.; Carlson, N.M., Donaldson, A.D.

1990-12-12

A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid. 3 figs.

Automated management of engineering infrastructure of pools of different purpose

Directory of Open Access Journals (Sweden)

Shirokov Lev Alekseevich

2016-10-01

Full Text Available Pools play an important role in people’s life. They answer people’s demand in rest and improve their health. At the same time pools are rather important for industrial use, for example in construction industry. In order to solve different construction problems it is essential to investigate the influence of microclimatic parameters on construction materials and structures. For this aim pools are in demand as special test sites for construction materials and structures in different environmental conditions including the case of a direct water impact. The efficient use of pools presupposes the necessity of constant hydroclimatic contro: air humidity and temperature, water temperature, chemical composition of water and air. Classification of pools of different purposes is presented in the article. The author considers the main problems of operation of pools as objects with complicated air-and-water environment. The questions of maintaining optimal microclimatic parameters in a pool are considered. The necessity of use of the control system of a microclimate, its efficiency, profitability and social effect of its implementation is described. A mathematical model of the thermal mode of a pool area is constructed. The process of indoor temperature regulation in the pool is considered.

Crust formation and its effect on the molten pool coolability

Energy Technology Data Exchange (ETDEWEB)

Park, R.J.; Lee, S.J.; Sim, S.K. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-09-01

Experimental and analytical studies of the crust formation and its effect on the molten pool coolability have been performed to examine the crust formation process as a function of boundary temperatures as well as to investigate heat transfer characteristics between molten pool and overlying water in order to evaluate coolability of the molten pool. The experimental test results have shown that the surface temperature of the bottom plate is a dominant parameter in the crust formation process of the molten pool. It is also found that the crust thickness of the case with direct coolant injection into the molten pool is greater than that of the case with a heat exchanger. Increasing mass flow rate of direct coolant injection to the molten pool does not affect the temperature of molten pool after the crust has been formed in the molten pool because the crust behaves as a thermal barrier. The Nusselt number between the molten pool and the coolant of the case with no crust formation is greater than that of the case with crust formation. The results of FLOW-3D analyses have shown that the temperature distribution contributes to the crust formation process due to Rayleigh-Benard natural convection flow.

Backfitting swimming pool reactors

International Nuclear Information System (INIS)

Roebert, G.A.

1978-01-01

Calculations based on measurements in a critical assembly, and experiments to disclose fuel element surface temperatures in case of accidents like stopping of primary coolant flow during full power operation, have shown that the power of the swimming pool type research reactor FRG-2 (15 MW, operating since 1967) might be raised to 21 MW within the present rules of science and technology, without major alterations of the pool buildings and the cooling systems. A backfitting program is carried through to adjust the reactor control systems of FRG-2 and FRG-1 (5 MW, housed in the same reactor hall) to the present safety rules and recommendations, to ensure FRG-2 operation at 21 MW for the next decade. (author)

Tax credits and purchasing pools: will this marriage work?

Science.gov (United States)

Trude, S; Ginsburg, P B

2001-04-01

Bipartisan interest is growing in Congress for using federal tax credits to help low-income families buy health insurance. Regardless of the approach taken, tax credit policies must address risk selection issues to ensure coverage for the chronically ill. Proposals that link tax credits to purchasing pools would avoid risk selection by grouping risks similar to the way large employers do. Voluntary purchasing pools have had only limited success, however. This Issue Brief discusses linking tax credits to purchasing pools. It uses information from the Center for Studying Health System Change's (HSC) site visits to 12 communities as well as other research to assess the role of purchasing pools nationwide and the key issues and implications of linking tax credits and pools.

Design of inventory pools in spare part support operation systems

Science.gov (United States)

Mo, Daniel Y.; Tseng, Mitchell M.; Cheung, Raymond K.

2014-06-01

The objective of a spare part support operation is to fulfill the part request order with different service contracts in the agreed response time. With this objective to achieve different service targets for multiple service contracts and the considerations of inventory investment, it is not only important to determine the inventory policy but also to design the structure of inventory pools and the order fulfilment strategies. In this research, we focused on two types of inventory pools: multiple inventory pool (MIP) and consolidated inventory pool (CIP). The idea of MIP is to maintain separated inventory pools based on the types of service contract, while CIP solely maintains a single inventory pool regardless of service contract. Our research aims to design the inventory pool analytically and propose reserve strategies to manage the order fulfilment risks in CIP. Mathematical models and simulation experiments would be applied for analysis and evaluation.

Flashing oscillation in pool water

International Nuclear Information System (INIS)

Takamasa, Tomoji; Kondo, Koichi; Hazuku, Tatsuya

1996-01-01

This paper presents an experimental study of high-pressure saturated water discharging into the pool water. The purpose of the experiment is to clarify the phenomena that occur in blow-down of high-pressure saturated water from the pressure vessel into the water-filled containment in the case of a wall-crack accident or a LOCA in an advanced reactor. The results revealed that a flashing oscillation (FO) occurs when high-pressure saturated water discharges into the pool water, under specified experimental settings. The range of the flashing oscillates between a point very close to and some distance from the vent hole. The pressures in the vent tube and pool water vary according to the flashing oscillation. The pressure oscillation and frequency of flashing position might be caused by the balancing action between the supply of saturated water, flashing at the control volume and its condensation on the steam-water interface. A linear analysis was conducted using a spherical flashing bubble model. The period of the flashing oscillation in the experiments can be explained by theoretical analysis

Vitamin D Pooling Project

Science.gov (United States)

The Vitamin D Pooling Project of Rarer Cancers brought together investigators from 10 cohorts to conduct a large prospective epidemiologic study of the association between vitamin D status and seven rarer cancers.

Pooled versus separate measurements of tree-ring stable isotopes

Energy Technology Data Exchange (ETDEWEB)

Dorado Linan, Isabel, E-mail: isabel@gfz-potsdam.de [Universitat de Barcelona, Departament d' Ecologia, Diagonal 645, 08028, Barcelona (Spain); German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany); Gutierrez, Emilia, E-mail: emgutierrez@ub.edu [Universitat de Barcelona, Departament d' Ecologia, Diagonal 645, 08028, Barcelona (Spain); Helle, Gerhard, E-mail: ghelle@gfz-potsdam.de [German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany); Heinrich, Ingo, E-mail: heinrich@gfz-potsdam.de [German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany); Andreu-Hayles, Laia, E-mail: laiandreu@ub.edu [Universitat de Barcelona, Departament d' Ecologia, Diagonal 645, 08028, Barcelona (Spain); Tree-Ring Laboratory, Lamont-Doherty Earth Observatory of Columbia University, Palisades NY (United States); Planells, Octavi, E-mail: leocarpus@hotmail.com [Universitat de Barcelona, Departament d' Ecologia, Diagonal 645, 08028, Barcelona (Spain); Leuenberger, Markus, E-mail: leuenberger@climate.unibe.ch [Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland); Oeschger Centre of Climate Change Research, University of Bern, Zaehringerstrasse 25, 3012 Bern (Switzerland); Buerger, Carmen, E-mail: buerger@gfz-potsdam.de [German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany); Schleser, Gerhard, E-mail: schleser@gfz-potsdam.de [German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany)

2011-05-01

{delta}{sup 13}C and {delta}{sup 18}O of tree rings contain time integrated information about the environmental conditions weighted by seasonal growth dynamics and are well established as sources of palaeoclimatic and ecophysiological data. Annually resolved isotope chronologies are frequently produced by pooling dated growth rings from several trees prior to the isotopic analyses. This procedure has the advantage of saving time and resources, but precludes from defining the isotopic error or statistical uncertainty related to the inter-tree variability. Up to now only a few studies have compared isotope series from pooled tree rings with isotopic measurements from individual trees. We tested whether or not the {delta}{sup 13}C and the {delta}{sup 18}O chronologies derived from pooled and from individual tree rings display significant differences at two locations from the Iberian Peninsula to assess advantages and constraints of both methodologies. The comparisons along the period 1900-2003 reveal a good agreement between pooled chronologies and the two mean master series which were created by averaging raw individual values (Mean) or by generating a mass calibrated mean (MassC). In most of the cases, pooled chronologies show high synchronicity with averaged individual samples at interannual scale but some differences also show up especially when comparing {delta}{sup 18}O decadal to multi-decadal variations. Moreover, differences in the first order autocorrelation among individuals may be obscured by pooling strategies. The lack of replication of pooled chronologies prevents detection of a bias due to a higher mass contribution of one sample but uncertainties associated with the analytical process itself, as sample inhomogeneity, seems to account for the observed differences. - Research Highlights: {yields} Pooled {delta}{sup 13}C and {delta}{sup 18}O chronologies are expected to be similar to the mean. {yields} Empirical pooled chronologies {delta}{sup 13}C and

Pooled versus separate measurements of tree-ring stable isotopes

International Nuclear Information System (INIS)

Dorado Linan, Isabel; Gutierrez, Emilia; Helle, Gerhard; Heinrich, Ingo; Andreu-Hayles, Laia; Planells, Octavi; Leuenberger, Markus; Buerger, Carmen; Schleser, Gerhard

2011-01-01

δ 13 C and δ 18 O of tree rings contain time integrated information about the environmental conditions weighted by seasonal growth dynamics and are well established as sources of palaeoclimatic and ecophysiological data. Annually resolved isotope chronologies are frequently produced by pooling dated growth rings from several trees prior to the isotopic analyses. This procedure has the advantage of saving time and resources, but precludes from defining the isotopic error or statistical uncertainty related to the inter-tree variability. Up to now only a few studies have compared isotope series from pooled tree rings with isotopic measurements from individual trees. We tested whether or not the δ 13 C and the δ 18 O chronologies derived from pooled and from individual tree rings display significant differences at two locations from the Iberian Peninsula to assess advantages and constraints of both methodologies. The comparisons along the period 1900-2003 reveal a good agreement between pooled chronologies and the two mean master series which were created by averaging raw individual values (Mean) or by generating a mass calibrated mean (MassC). In most of the cases, pooled chronologies show high synchronicity with averaged individual samples at interannual scale but some differences also show up especially when comparing δ 18 O decadal to multi-decadal variations. Moreover, differences in the first order autocorrelation among individuals may be obscured by pooling strategies. The lack of replication of pooled chronologies prevents detection of a bias due to a higher mass contribution of one sample but uncertainties associated with the analytical process itself, as sample inhomogeneity, seems to account for the observed differences. - Research Highlights: → Pooled δ 13 C and δ 18 O chronologies are expected to be similar to the mean. → Empirical pooled chronologies δ 13 C and δ 18 O and the mean show a high synchronicity. → Pooled chronologies differ

Suncatcher and cool pool. Project report

Energy Technology Data Exchange (ETDEWEB)

Hammond, J.

1981-03-01

The Suncatcher is a simple, conical solar concentrating device that captures light entering clerestory windows and directs it onto thermal storage elements at the back of a south facing living space. The cone shape and inclination are designed to capture low angle winter sunlight and to reflect away higher angle summer sunlight. It is found that winter radiation through a Suncatcher window is 40 to 50% higher than through an ordinary window, and that the average solar fraction is 59%. Water-filled steal culvert pipes used for thermal storage are found to undergo less stratification, and thus to be more effective, when located where sunlight strikes the bottom rather than the top. Five Suncatcher buildings are described. Designs are considered for 32/sup 0/, 40/sup 0/ and 48/sup 0/ north latitude, and as the latitude increases, the inclination angle of the cone should be lowered. The Cool Pool is an evaporating, shaded roof pond which thermosiphons cool water into water-filled columns within a building. Preliminary experiments indicate that the best shade design has unimpeded north sky view, good ventilation, complete summer shading, a low architectural profile, and low cost attic vent lowers work. Another series of experiments established the satisfactory performance of the Cool Pool on a test building using four water-filled cylinders, two cylinders, and two cylinders connected to the Cool Pool through a heat exchanger. Although an unshaded pool cools better at night than a shaded one, daytime heat gain far offsets this advantage. A vinyl waterbag heat exchanger was developed for use with the Cool Pool. (LEW)

Flow dynamics of volume-heated boiling pools

International Nuclear Information System (INIS)

Ginsberg, T.; Jones, O.C.; Chen, J.C.

1979-01-01

Safety analyses of fast breeder reactors require understanding of the two-phase fluid dynamic and heat transfer characteristics of volume-heated boiling pool systems. Design of direct contact three-phase boilers, of practical interest in the chemical industries also requires understanding of the fundamental two-phase flow and heat transfer behavior of volume boiling systems. Several experiments have been recently reported relevant to the boundary heat-loss mechanisms of boiling pool systems. Considerably less is known about the two-phase fluid dynamic behavior of such systems. This paper describes an experimental investigation of the steady-state flow dynamics of volume-heated boiling pool systems

Laser surveillance systems for fuel storage pools

International Nuclear Information System (INIS)

Boeck, H.

1985-06-01

A Laser Surveillance System (LASSY) as a new safeguards device has been developed under the IAEA research contract No. 3458/RB at the Atominstitut Wien using earlier results by S. Fiarman. This system is designed to act as a sheet of light covering spent fuel assemblies in spent fuel storage pools. When movement of assemblies takes place, LASSY detects and locates the position of the movement in the pool and when interrogated, presents a list of pool positions and times of movement to the safeguards inspector. A complete prototype system was developed and built. Full scale tests showed the principal working capabilities of a LASSY underwater

Spent fuel pool spray cooling system for the AP1000 {sup registered}

Energy Technology Data Exchange (ETDEWEB)

Vujic, Zoran; Sassen, Felix; Tietsch, Wolfgang [Westinghouse Electric Germany GmbH, Mannheim (Germany)

2013-07-01

The AP1000 {sup registered} plant design features multiple, diverse lines of defense to ensure spent fuel cooling can be maintained for Design Basis Events and Beyond Design Basis Accidents (BDBA). The AP1000 {sup registered} plant lines of defense with respect to Spent Fuel Pool (SFP) cooling are as follows: 1. During normal and abnormal conditions, defense-in-depth and duty systems provide highly reliable SFP cooling, supplied by offsite AC power or the onsite Standby Diesel Generators. 2. For unlikely events with extended loss of AC power (i.e. station black-out) and/or loss of heat sink, spent fuel cooling can be still provided indefinitely by: 2a. Passive systems, requiring minimal or no operator actions, sufficient for at least 72 hours under all possible loading conditions. 2b. After 3 days, several different means are provided to continue SFP cooling using installed plant equipment as well as off-site equipment with built-in connections. 3. Even for BDBA with postulated SFP damage and multiple failures in the passive safety-related systems and in the defense-in-depth active systems, the AP1000 {sup registered} SFP Spray System provides an additional line of defense to prevent spent fuel damage. (orig.)

Thermophysical modeling of volatile fission product release from a debris pool

International Nuclear Information System (INIS)

Yun, J. I.; Suh, K. Y.; Kang, C. S.

1999-01-01

A model is described for fission product release from the debris pool in the lower plenum of the reactor pressure vessel. In the pool, turbulent natural convection flow is formed due to homogeneous internal heat generation. Using the best-known correlations, heat transfer at the curved bottom and the top of the pool may be calculated. Volatile fission product gases in the pool nucleate and diffuse to bubbles. Both the homogeneous nucleation and heterogeneous nucleation are considered. The bubble nucleation, growth, coalescence and loss due to rise is modeled pursuant to bubble dynamics. If the pressure and temperature of the pool are very high, homogeneous nucleation that accounts for effect of decrease in the pool pressure can occur. The effect of the bubble-to-pool interfacial tension and the pool pressure on the nucleation rate is investigated in this work

Review of steam jet condensation in a water pool

International Nuclear Information System (INIS)

Kim, Y. S.; Song, C. H.; Park, C. K.; Kang, H. S.; Jeon, H. G.; Yoon, Y. J.

2002-01-01

In the advanced nuclear power plants including APR1400, the SDVS is adopted to increase the plant safety using the concept of feed-and-bleed operation. In the case of the TLOFW, the POSRV located at the top of the pressurizer is expected to open due to the pressurization of the reactor coolant system and discharges steam and/or water mixture into the water pool, where the mixture is condensed. During the condensation of the mixture, thermal-hydraulic loads such as pressure and temperature variations are induced to the pool structure. For the pool structure design, such thermal-hydraulic aspects should be considered. Understanding the phenomena of the submerged steam jet condensation in a water pool is helpful for system designers to design proper pool structure, sparger, and supports etc. This paper reviews and evaluates the steam jet condensation in a water pool on the physical phenomena of the steam condensation including condensation regime map, heat transfer coefficient, steam plume, steam jet condensation load, and steam jet induced flow

Code Development of Radioactive Aerosol Scrubbing in Pool-Injection Zone

Energy Technology Data Exchange (ETDEWEB)

Jo, Hyun Joung; Ha, Kwang Soon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Jang, Dong Soon [Chungnam National University, Daejeon (Korea, Republic of)

2015-10-15

The pool scrubbing models were reviewed and an aerosol scrubbing code has been prepared to calculate decontamination factor through the injection zone. The developed code has been verified using the experimental results and evaluated parametrically on the input variables. In injection zone, the initial steam condensation was most effective mechanism for the aerosol removal, and the steam fraction and pool temperature were highly affected on the decontamination factor by initial steam condensation. The aerosol scrubbing code will be updated to evaluate the decontamination factor at rise zone and finally whole pool scrubber phenomena. If a severe accident occurs in a nuclear power plant (NPP), the aerosol and gaseous fission products might be produced in the reactor vessel, and then released to the environment after the containment failure. FCVS (Filtered Containment Venting System) is one of the severe accident mitigation systems for retaining the containment integrity by discharging the high-temperature and high-pressure fission products to the environment after passing through the filtration system. In general, the FCVS is categorized into two types, wet and dry types. The scrubbing pool could play an important role in the wet type FCVS because a large amount of aerosol is captured in the water pool. The pool scrubbing phenomena have been modelled and embedded in several computer codes, such as SPARC (Suppression Pool Aerosol Removal Code), BUSCA (BUbble Scrubbing Algorithm) and SUPRA (Suppression Pool Retention Analysis). These codes aim at simulating the pool scrubbing process and estimating the decontamination factors (DFs) of the radioactive aerosol and iodine gas in the water pool, which is defined as the ratio of initial mass of the specific radioactive material to final massy after passing through the water pool. The pool scrubbing models were reviewed and an aerosol scrubbing code has been prepared to calculate decontamination factor through the injection

Competition and power pooling in the electricity industry

International Nuclear Information System (INIS)

Jasinski, P.; Yarrow, G.; Fusaro, P.

1995-01-01

Two contributions to the debate on power pooling and competition in the electricity supply industry are presented. In the first, the situation in England and Wales where power pooling was introduced shortly before privatization is analysed. Pooling has existed for many years in the USA but as an inter-generator arrangement designed to optimize production and costs. The British system sought in addition to establish a spot market in which bulk buyers as well as bulk suppliers could participate. There are however obvious weaknesses in the pool as a competitive market and it is argued that a combination of pooling arrangements and longer-term bilateral supply contracts are more likely to offer the prospect of workably competitive and efficient outcomes. The second contribution discusses how competitive markets will evolve in the USA under the new regime of less onerous regulation heralded by the Energy Policy Act if 1992 and the emergence of electricity trading markets which followed. In particular, the proposal by the California Public Utility commission favouring a mandatory Poolco is examined. Poolco would operate the transmission grid and dispatch generating plants while the utilities would retain ownership of transmission facilities and be required to supply the pool. This is seen as representing only partial deregulation and not to be consistent with moves to further competition and encourage free markets. (U.K.)

Pooling strategies for St Petersburg gamblers

OpenAIRE

Csörgö, Sandor; Simons, Gordon

2006-01-01

Peter offers to play exactly one St Petersburg game with each of [math] players, Paul [math] , [math] , Paul [math] , whose conceivable pooling strategies are described by all possible probability distributions [math] . Comparing infinite expectations, we characterize among all [math] those admissible strategies for which the pooled winnings, each distributed as [math] , yield a finite added value for each and every one of Paul [math] , [math] , Paul [math] in comparison with their individual...

Swimming pool special; Zwembadspecial

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-05-15

This issue includes a few articles and messages on the use of heat pump systems in swimming pools. [Dutch] Dit nummer bevat onder meer een paar artikelen over het gebruik van warmtepompsystemen in zwembaden.

The warm pool in the Indian Ocean

Digital Repository Service at National Institute of Oceanography (India)

Vinayachandran, P.N.; Shetye, S.R.

is larger and warmer, a peculiarity of the pool in the Indian Ocean is its seasonal variation. The surface area of the pool changes from 24 x 106 km2 in April to 8 x 106 km2 in September due to interaction with the southwest monsoon. The annual cycles of sea...

Steam blowdown experiments with the condensation pool test rig

International Nuclear Information System (INIS)

Purhonen, H.; Puustinen, M.; Laine, J.; Raesaenen, A.; Kyrki-Rajamaeki, R.; Vihavainen, J.

2005-01-01

During a possible loss-of-coolant accident (Local) a large amount of non-condensable (nitrogen) and condensable (steam) gas is blown from the upper drywell of the containment to the condensation pool through the blowdown pipes at the boiling water reactors (BWRs). The wet well pool serves as the major heat sink for condensation of steam. The blowdown causes both dynamic and structural loads to the condensation pool. There might also be a risk that the gas discharging to the pool could push its way to the emergency core cooling systems (ECCS) and undermine their performance. (author)

Simulation of pool scrubbing experiments using BUSCA

International Nuclear Information System (INIS)

Dehbi, A.; Guentay, S.

1994-01-01

BUSCA-PSI is a computer code which predicts the aerosol scrubbing taking place when gas bubbles containing fission products rise through stagnant pools of water after a postulated severe accident. A Lagrangian formulation is adopted to follow the path of a bubble as it rises toward the surface of the pool. The BUSCA model includes most aerosol removal mechanisms which are thought to be significant, namely: Jet Impaction at tile orifice, Convection/Diffusiophoresis during steam condensation, Thermophoresis, Sedimentation, Centrifugal Impaction during bubble rise, and Brownian Diffusion. The hydraulic modelling offers a variety of options for the initial globule volume, the stable bubble size, tile bubble rise velocity, and the bubble shape. The heat and mass transfer part of tile model uses correlations found in the relevant literature. BUSCA simulations were performed to determine the decontamination factor (DF) dependence on key aerosol and thermal hydraulic parameters. The decontamination factor increases with height, pool temperature subcooling, and steam content. The decontamination factor exhibits a parabolic dependence on the particle radius. At low particle sizes, the DF is high due to Brownian Diffusion which is the dominant removal mechanism. The DF hits a minimum and then increases with particle size as Centrifugal Impaction and Sedimentation become important. In separate calculations, BUSCA was used to the simulate the aerosol scrubbing experiments performed by EPRI. For cold pool tests, the predicted scrubbing efficiencies were in a good, conservative agreement with the data for both Tin and CsI, and the discrepancies were within the reported measurement errors. For hot pool tests, the code systematically underpredicted the scrubbing DF's; this is potentially due to condensation in the gas space above the pool, a situation not currently modelled by BUSCA. The code was also tested against data produced by the Tepco-Toshiba-Hitachi experiments. The

Study on water evaporation rate from indoor swimming pools

Directory of Open Access Journals (Sweden)

Rzeźnik Ilona

2017-01-01

Full Text Available The air relative humidity in closed spaces of indoor swimming pools influences significantly on users thermal comfort and the stability of the building structure, so its preservation on suitable level is very important. For this purpose, buildings are equipped with HVAC systems which provide adequate level of humidity. The selection of devices and their technical parameters is made using the mathematical models of water evaporation rate in the unoccupied and occupied indoor swimming pool. In the literature, there are many papers describing this phenomena but the results differ from each other. The aim of the study was the experimental verification of published models of evaporation rate in the pool. The tests carried out on a laboratory scale, using model of indoor swimming pool, measuring 99cm/68cm/22cm. The model was equipped with water spray installation with six nozzles to simulate conditions during the use of the swimming pool. The measurements were made for conditions of sports pools (water temperature 24°C and recreational swimming pool (water temperature 34°C. According to the recommendations the air temperature was about 2°C higher than water temperature, and the relative humidity ranged from 40% to 55%. Models Shah and Biasin & Krumm were characterized by the best fit to the results of measurements on a laboratory scale.

Peatland Open-water Pool Biogeochemistry: The Influence of Hydrology and Vegetation

Science.gov (United States)

Arsenault, J.; Talbot, J.; Moore, T. R.

2017-12-01

Peatland open-water pools are net sources of carbon to the atmosphere. However, their interaction with the surrounding peat remains poorly known. In a previous study, we showed that shallow pools are richer in nutrients than deep pools. While depth was the main driver of biogeochemistry variations across time and space, analyses also showed that pool's adjacent vegetation may have an influence on water chemistry. Our goal is to understand the relationship between the biogeochemistry of open-water pools and their surroundings in a subboreal ombrotrophic peatland of southern Quebec (Canada). To assess the influence of vegetation on pool water chemistry, we compare two areas covered with different types of vegetation: a forested zone dominated by spruce trees and an open area mostly covered by Sphagnum spp. To evaluate the direction of water (in or out of the pools), we installed capacitance water level probes in transects linking pools in the two zones. Wells were also installed next to each probe to collect peat pore water samples. Samples were taken every month during summer 2017 and analyzed for dissolved organic carbon, nitrogen and phosphorus, pH and specific UV absorbance. Preliminary results show differences in peat water chemistry depending on the dominant vegetation. In both zones, water levels fluctuations are disconnected between peat and the pools, suggesting poor horizontal water movement. Pool water chemistry may be mostly influenced by the immediate surrounding vegetation than by the local vegetation pattern. Climate and land-use change may affect the vegetation structure of peatlands, thus affecting pool biogeochemistry. Considering the impact of pools on the overall peatland capacity to accumulate carbon, our results show that more focus must be placed on pools to better understand peatland stability over time.

The atmospheric wet pool: definition and comparison with the oceanic warm pool

Institute of Scientific and Technical Information of China (English)

ZHANG Caiyun; CHEN Ge

2008-01-01

The oceanic warm pool (OWP) defined by sea surface temperature (SST) is known as the "heat reservoir" in the ocean. The warmest portion in the ocean mirrors the fact that the wettest region with the largest accumulation of water vapor (WV) in the atmosphere, termed atmospheric wet pool (AWP), should be identified because of the well-known Clausius-Clapeyron relationship between SST and WV. In this study, we used 14-year simultaneous observations of WV and SST from January 1988 to December 2001 to define the AWP and investigate its coupling and co-variations with the OWP. The joint examination of the area variations, centroid locations, and zonal migrations of the AWP and OWP lead to a number of interesting findings. The results hopefully can contribute to our understanding of the air-sea interaction in general and characterization of El Nifio/La Nina events in particular.

Loss of spent fuel pool cooling PRA: Model and results

International Nuclear Information System (INIS)

Siu, N.; Khericha, S.; Conroy, S.; Beck, S.; Blackman, H.

1996-09-01

This letter report documents models for quantifying the likelihood of loss of spent fuel pool cooling; models for identifying post-boiling scenarios that lead to core damage; qualitative and quantitative results generated for a selected plant that account for plant design and operational practices; a comparison of these results and those generated from earlier studies; and a review of available data on spent fuel pool accidents. The results of this study show that for a representative two-unit boiling water reactor, the annual probability of spent fuel pool boiling is 5 x 10 -5 and the annual probability of flooding associated with loss of spent fuel pool cooling scenarios is 1 x 10 -3 . Qualitative arguments are provided to show that the likelihood of core damage due to spent fuel pool boiling accidents is low for most US commercial nuclear power plants. It is also shown that, depending on the design characteristics of a given plant, the likelihood of either: (a) core damage due to spent fuel pool-associated flooding, or (b) spent fuel damage due to pool dryout, may not be negligible

Infections Unlikely to be Spread Through Swimming Pools

Science.gov (United States)

... Water Home Infections Unlikely to be Spread Through Swimming Pools Language: English (US) Español (Spanish) Recommend on ... included below. Infections Unlikely to be Spread by Swimming Pools Head Lice Head lice are unlikely to ...

Regional variation in the biogeochemical and physical characteristics of natural peatland pools.

Science.gov (United States)

Turner, T Edward; Billett, Michael F; Baird, Andy J; Chapman, Pippa J; Dinsmore, Kerry J; Holden, Joseph

2016-03-01

Natural open-water pools are a common feature of northern peatlands and are known to be an important source of atmospheric methane (CH4). Pool environmental variables, particularly water chemistry, vegetation community and physical characteristics, have the potential to exert strong controls on carbon cycling in pools. A total of 66 peatland pools were studied across three regions of the UK (northern Scotland, south-west Scotland, and Northern Ireland). We found that within-region variability of pool water chemistry was low; however, for many pool variables measured there were significant differences between regions. PCA analysis showed that pools in SW Scotland were strongly associated with greater vegetative cover and shallower water depth which is likely to increase dissolved organic carbon (DOC) mineralisation rates, whereas pools in N Scotland were more open and deeper. Pool water DOC, particulate organic carbon and dissolved CH4 concentrations were significantly different between regions. Pools in Northern Ireland had the highest concentrations of DOC (mean=14.5 mg L(-1)) and CH4 (mean=20.6 μg C L(-1)). Chloride and sulphate concentrations were significantly higher in the pools in N Scotland (mean values 26.3 and 2.40 mg L(-1), respectively) than elsewhere, due to a stronger marine influence. The ratio of UV absorbance at 465 nm to absorbance at 665 nm for pools in Northern Ireland indicated that DOC was sourced from poorly humified peat, potentially increasing the bioavailability and mineralisation of organic carbon in pools compared to the pools elsewhere. This study, which specifically aims to address a lack of basic biogeochemical knowledge about pool water chemistry, clearly shows that peatland pools are highly regionally variable. This is likely to be a reflection of significant regional-scale differences in peatland C cycling. Copyright © 2015 Elsevier B.V. All rights reserved.

Ergonomic evaluation of a wearable assistive device for overhead work.

Science.gov (United States)

Rashedi, Ehsan; Kim, Sunwook; Nussbaum, Maury A; Agnew, Michael J

2014-01-01

Overhead work is an important risk factor for upper extremity (UE) musculoskeletal disorders. We examined the potential of a mechanical arm and an exoskeletal vest as a wearable assistive device (WADE) for overhead work. Twelve participants completed 10 minutes of simulated, intermittent overhead work, using each of three payloads (1.1, 3.4 and 8.1 kg) and with/without the WADE. Ratings of perceived discomfort (RPDs) and electromyography (EMG) were obtained for the upper arms, shoulders and low back. Using the WADE, UE RPDs decreased by ∼50% with the heavier payloads, whereas smaller (∼25%) and non-significant increases in low-back RPDs were found and were relatively independent of payload. Changes in RPDs with WADE use were consistent with physical demands indicated by EMG, though EMG-based differences in fatigue were less apparent. Participants generally preferred using the WADE, particularly with heavier payloads. These results supported the potential utility of a WADE as an intervention for overhead work.

Pressure supression pool thermal mixing

International Nuclear Information System (INIS)

Cook, D.H.

1984-10-01

A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model developed in this work produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing is verified by comparing the model-predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

Pressure suppression pool thermal mixing

International Nuclear Information System (INIS)

Cook, D.H.

1984-01-01

A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing model is verified by comparing the model predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

Test Area North Pool Stabilization Project: Environmental assessment

International Nuclear Information System (INIS)

1996-05-01

The Test Area North (TAN) Pool is located within the fenced TAN facility boundaries on the Idaho National Engineering Laboratory (INEL). The TAN pool stores 344 canisters of core debris from the March, 1979, Three Mile Island (TMI) Unit 2 reactor accident; fuel assemblies from Loss-of-Fluid Tests (LOFT); and Government-owned commercial fuel rods and assemblies. The LOFT and government owned commercial fuel rods and assemblies are hereafter referred to collectively as open-quotes commercial fuelsclose quotes except where distinction between the two is important to the analysis. DOE proposes to remove the canisters of TMI core debris and commercial fuels from the TAN Pool and transfer them to the Idaho Chemical Processing Plant (ICPP) for interim dry storage until an alternate storage location other than at the INEL, or a permanent federal spent nuclear fuel (SNF) repository is available. The TAN Pool would be drained and placed in an industrially and radiologically safe condition for refurbishment or eventual decommissioning. This environmental assessment (EA) identifies and evaluates environmental impacts associated with (1) constructing an Interim Storage System (ISS) at ICPP; (2) removing the TMI and commercial fuels from the pool and transporting them to ICPP for placement in an ISS, and (3) draining and stabilizing the TAN Pool. Miscellaneous hardware would be removed and decontaminated or disposed of in the INEL Radioactive Waste Management Complex (RWMC). This EA also describes the environmental consequences of the no action alternative

Structural analysis of the reactor pool for the RRRP

International Nuclear Information System (INIS)

Alberro, J.G.; Abbate, A.D.

2005-01-01

The purpose of the present document is to describe the structural design of the Reactor Pool relevant to the RRRP (Replacement Research Reactor Project) for the Australian Nuclear Science and Technology Organisation. The structural analysis required coordinated design, engineering, analysis, and fabrication efforts. The pool has been designed, manufactured, and inspected following as guideline the ASME Boiler and Pressure Vessel Code, which defines the requirements for the pool to withstand hydrostatic and mechanical forces, ensuring its integrity throughout its lifetime. Standard off-the-shelf finite element programs (Nastran and Ansys codes) were used to evaluate the pool and further qualify the design and its construction. Both global and local effect analyses were carried out. The global analysis covers the structural integrity of the pool wall (6 mm thick) considering the different load states acting on it, namely hydrostatic pressure, thermal expansion, and seismic event. The local analysis evaluates the structural behaviour of the pool at specific points resulting from the interaction among components. It is confirmed that maximum stresses and displacements fall below the allowable values required by the ASME Boiler and Pressure Vessel Code. The water pressure analysis was validated by means of a hydrostatic test. (authors)

PIV measurements of turbulent jet and pool mixing produced by a steam jet discharge in a subcooled water pool

International Nuclear Information System (INIS)

Choo, Yeon Jun; Song, Chul-Hwa

2010-01-01

This experimental research is on the fluid-dynamic features produced by a steam injection into a subcooled water pool. The relevant phenomena could often be encountered in water cooled nuclear power plants. Two major topics, a turbulent jet and the internal circulation produced by a steam injection, were investigated separately using a particle image velocimetry (PIV) as a non-intrusive optical measurement technique. Physical domains of both experiments have a two-dimensional axi-symmetric geometry of which the boundary and initial conditions can be readily and well defined. The turbulent jet experiments with the upward discharging configuration provide the parametric values for quantitatively describing a turbulent jet such as the self-similar velocity profile, central velocity decay, spreading rate, etc. And in the internal circulation experiments with the downward discharging configuration, typical flow patterns in a whole pool region are measured in detail, which reveals both the local and macroscopic characteristics of the mixing behavior in a pool. This quantitative data on the condensing jet-induced mixing behavior in a pool could be utilized as benchmarking for a CFD simulation of relevant phenomena.

Experience on Maintenance of Thai Research Reactor's 'Small-Section' Pool

International Nuclear Information System (INIS)

Tippayakul, Chanatip

2013-01-01

The reactor pool of TRR-1/M1 has been used since 1962 when the reactor building was constructed. Periodic maintenance of the reactor pool has been conducted by cleaning the pool surface and re-painting with epoxy coating. The TRR-1/M1 pool basically consists of two sections referred as 'large-section' and 'small-section'. The latest re-painting activity of the 'large-section' pool was performed in 2006 but the 'small-section' pool had not been re-painted for more than 10 years. Therefore, to assure that the 'small-section' pool can maintain leak-proof condition, the re-painting of the 'small-section' pool was performed in the early 2012. A project team was organized specially for this project and a detailed execution plan was developed. The project activities include removing foreign objects and highly activated materials from the pool section, cleaning, inspecting, re-painting the pool surface and testing for water leaks. Preparation of the repainting activities had begun 2 years in advance. During the time, the reactor core had been relocated to operate in the large-section pool away from the working area in order to minimize radioactivity. The challenge of this project was to handle 4 sets of highly radioactive bolts and nuts which support the weight of the 'void tank' irradiation facility. These bolts and nuts were made from stainless steel and had been in the flux region since the installation of the 'void tank' irradiation facility approximately 30 years ago. Dose rate measurement at the contacts of these bolts and nuts were found to be in the range of 10 . 20 R/hr. The strategy to minimize the dose rate of the workers to conduct the pool repainting in the area was to remove the bolts and nuts and replace with new ones before entering the area. Special tools were improvised in order to remove the bolts and nuts under water. During the execution of the project, close radiation monitoring was performed by the radiation protection team. The project was conducted

Phytobenthic communities of intertidal rock pools in the eastern islands of Azores and their relation to position on shore and pool morphology

OpenAIRE

Wallenstein, Francisco; Peres, Sara D.; Xavier, Emanuel D.; Neto, Ana I.

2010-01-01

This study aimed to characterize algal composition inside rock-pools from two islands of the Azores archipelago (São Miguel and Santa Maria) and relate it to shore height and pool morphology. Pools were categorized as upper, medium and lower intertidal according to the surrounding communities. Maximum depth and surface area were used to reflect morphology and qualitative sampling to evaluate algal species richness. PRIMER software assessed the similarity across islands, sites, shore height...

16 CFR 1633.5 - Prototype pooling and confirmation testing requirements.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Prototype pooling and confirmation testing... Prototype pooling and confirmation testing requirements. (a) Prototype pooling. One or more manufacturers may rely on a qualified prototype produced by another manufacturer or prototype developer provided...

Non-electric applications of pool-type nuclear reactors

International Nuclear Information System (INIS)

Adamov, E.O.; Cherkashov, Yu.M.; Romenkov, A.A.

1997-01-01

This paper recommends the use of pool-type light water reactors for thermal energy production. Safety and reliability of these reactors were already demonstrated to the public by the long-term operation of swimming pool research reactors. The paper presents the design experience of two projects: Apatity Underground Nuclear Heating Plant and Nuclear Sea-Water Desalination Plant. The simplicity of pool-type reactors, the ease of their manufacturing and maintenance make this type of a heat source attractive to the countries without a developed nuclear industry. (author). 6 figs, 1 tab

Addressing data privacy in matched studies via virtual pooling.

Science.gov (United States)

Saha-Chaudhuri, P; Weinberg, C R

2017-09-07

Data confidentiality and shared use of research data are two desirable but sometimes conflicting goals in research with multi-center studies and distributed data. While ideal for straightforward analysis, confidentiality restrictions forbid creation of a single dataset that includes covariate information of all participants. Current approaches such as aggregate data sharing, distributed regression, meta-analysis and score-based methods can have important limitations. We propose a novel application of an existing epidemiologic tool, specimen pooling, to enable confidentiality-preserving analysis of data arising from a matched case-control, multi-center design. Instead of pooling specimens prior to assay, we apply the methodology to virtually pool (aggregate) covariates within nodes. Such virtual pooling retains most of the information used in an analysis with individual data and since individual participant data is not shared externally, within-node virtual pooling preserves data confidentiality. We show that aggregated covariate levels can be used in a conditional logistic regression model to estimate individual-level odds ratios of interest. The parameter estimates from the standard conditional logistic regression are compared to the estimates based on a conditional logistic regression model with aggregated data. The parameter estimates are shown to be similar to those without pooling and to have comparable standard errors and confidence interval coverage. Virtual data pooling can be used to maintain confidentiality of data from multi-center study and can be particularly useful in research with large-scale distributed data.

Presence and select determinants of organophosphate flame retardants in public swimming pools

International Nuclear Information System (INIS)

Teo, Tiffany L.L.; Coleman, Heather M.; Khan, Stuart J.

2016-01-01

The occurrence of five organophosphate flame retardants (PFRs) consisting of tributyl phosphate (TNBP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tris(1.3-dichloro-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) in swimming pools were investigated. Fifteen chlorinated public swimming pools were sampled, including indoor pools, outdoor pools and spa pools. The analyses were carried out using isotope dilution gas chromatography tandem mass spectrometry. All five PFRs were detected in swimming pool waters with concentrations ranging from 5–27 ng/L (TNBP), 7–293 ng/L (TCEP), 62–1180 ng/L (TCIPP), 10–670 ng/L (TDCIPP) and 8–132 ng/L (TPHP). The concentrations of PFRs were generally higher in indoor swimming pools compared to outdoor swimming pools. In municipal water supplies, used to fill the swimming pools in three of the sampling locations, the five PFRs were all below the limit of quantifications, eliminating this as the source. Potential leaching of PFRs from commonly used swimming equipment, including newly purchased kickboards and swimsuits was investigated. These experiments revealed that PFRs leached from swimsuits, and may be a source of PFRs in swimming pools. A quantitative risk assessment revealed that the health risk to PFRs via swimming pools was generally low and below commonly applied health risk benchmarks. - Highlights: • TNBP, TCEP, TCIPP, TDCIPP and TPHP were detected in chlorinated swimming pools. • PFRs were below the LOQ in fill water samples collected from 3 locations. • TCIPP was observed to have the highest concentrations in swimming pools. • PFRs are leaching from swimsuits and may be a source in swimming pools. • Health risks through oral and dermal exposure to PFRs in swimming pools were low.

Presence and select determinants of organophosphate flame retardants in public swimming pools

Energy Technology Data Exchange (ETDEWEB)

Teo, Tiffany L.L., E-mail: tiffany.teo@unsw.edu.au [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Kensington NSW 2052 (Australia); Coleman, Heather M., E-mail: h.coleman@ulster.ac.uk [Nanotechnology and Integrated BioEngineering Centre, School of Engineering, University of Ulster, Jordanstown, County Antrim BT37 0QB, Northern Ireland (United Kingdom); Khan, Stuart J., E-mail: s.khan@unsw.edu.au [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Kensington NSW 2052 (Australia)

2016-11-01

The occurrence of five organophosphate flame retardants (PFRs) consisting of tributyl phosphate (TNBP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tris(1.3-dichloro-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) in swimming pools were investigated. Fifteen chlorinated public swimming pools were sampled, including indoor pools, outdoor pools and spa pools. The analyses were carried out using isotope dilution gas chromatography tandem mass spectrometry. All five PFRs were detected in swimming pool waters with concentrations ranging from 5–27 ng/L (TNBP), 7–293 ng/L (TCEP), 62–1180 ng/L (TCIPP), 10–670 ng/L (TDCIPP) and 8–132 ng/L (TPHP). The concentrations of PFRs were generally higher in indoor swimming pools compared to outdoor swimming pools. In municipal water supplies, used to fill the swimming pools in three of the sampling locations, the five PFRs were all below the limit of quantifications, eliminating this as the source. Potential leaching of PFRs from commonly used swimming equipment, including newly purchased kickboards and swimsuits was investigated. These experiments revealed that PFRs leached from swimsuits, and may be a source of PFRs in swimming pools. A quantitative risk assessment revealed that the health risk to PFRs via swimming pools was generally low and below commonly applied health risk benchmarks. - Highlights: • TNBP, TCEP, TCIPP, TDCIPP and TPHP were detected in chlorinated swimming pools. • PFRs were below the LOQ in fill water samples collected from 3 locations. • TCIPP was observed to have the highest concentrations in swimming pools. • PFRs are leaching from swimsuits and may be a source in swimming pools. • Health risks through oral and dermal exposure to PFRs in swimming pools were low.

Mathematical modeling of the energy consumption of heated swimming pools

Energy Technology Data Exchange (ETDEWEB)

Le Bel, C.; Millette, J. [LTE Shawinigan, Shawinigan, PQ (Canada)

2007-07-01

A mathematical model was developed to estimate the water temperature of a residential swimming pool. The model can compare 2 different situations and, if local climatic conditions are known, it can accurately predict energy costs of the pool relative to the total energy consumption of the house. When used with the appropriate energy transfer coefficient and weather file, the model can estimate the water temperature of a residential swimming pool having specific characteristics, such as in-ground, above-ground, heated or non-heated. The model is suitable for determining residential loads. It can be applied to different pool types and sizes, for different water heating scenarios and different climatic regions. Data obtained from the monitoring of water temperature and electricity use of 57 residential swimming pools was used to validate the model. In addition, 5 above-ground pools were installed on the property of LTE Shawinigan to allow for a more detailed study of the parameters involved in the thermal balance of a pool. The mathematical model, based on a global heat transfer coefficient, can determine the effect of a solar blanket and the effect of water volume. 14 refs., 5 tabs., 11 figs.

Compact fuel storage rack for fuel pools

International Nuclear Information System (INIS)

Parras, F.; Louvat, J.P.

1986-01-01

ETS LEMER and FRAMATOME propose a new compact storage rack. This rack permits a considerable increase of the storage capacity of cooling pools. A short description of the structure and the components is presented, to propose racks that are: . Inalterable, . Compact, . Insensitive to earthquakes. Installation in pools already in operation is simplified by their light structure and the bearing device [fr

Income pooling within families

DEFF Research Database (Denmark)

Bonke, Jens; Uldall-Poulsen, Hans

This paper analyses the phenomenon of income-pooling by applying the Danish household expenditure survey, merged with authoritative register information. Responses to additional questions on income sharing among 1696 couples also allows us to analyses whether the intra-household distribution...

Health impact of disinfection by-products in swimming pools

Directory of Open Access Journals (Sweden)

Cristina M. Villanueva

2012-12-01

Full Text Available This article is focused on the epidemiological evidence on the health impacts related to disinfection by-products (DBPs in swimming pools, which is a chemical hazard generated as an undesired consequence to reduce the microbial pathogens. Specific DBPs are carcinogenic, fetotoxic and/or irritant to the airways according to experimental studies. Epidemiological evidence shows that swimming in pools during pregnancy is not associated with an increased risk of reproductive outcomes. An epidemiological study suggested an increased risk of bladder cancer with swimming pool attendance, although evidence is inconclusive. A higher prevalence of respiratory symptoms including asthma is found among swimming pool workers and elite swimmers, although the causality of this association is unclear. The body of evidence in children indicates that asthma is not increased by swimming pool attendance. Overall, the available knowledge suggests that the health benefits of swimming outweigh the potential health risks of chemical contamination. However, the positive effects of swimming should be enhanced by minimising potential risks.

Characteristics of fission product release from a molten pool

International Nuclear Information System (INIS)

Yun, J.I.; Suh, K.Y.; Kang, C.S.

2001-01-01

The volatile fission products are released from the debris pool, while the less volatile fission products tend to remain as condensed phases because of their low vapor pressure. The release of noble gases and the volatile fission products is dominated by bubble dynamics. The release of the less volatile fission products from the pool can be analyzed based on mass transport through a liquid with the convection flow. The physico-numerical models were orchestrated from existing submodels in various disciplines of engineering to estimate the released fraction of fission products from a molten pool. It was assumed that the pool has partially filled hemispherical geometry. For the high pool pressure, the diameter of the bubbles at detachment was calculated utilizing the Cole and Shulman correlation with the effect of system pressure. Sensitivity analyses were performed and results of the numerical calculations were compared with analysis results for the TMI-2 accident. (author)

13 CFR 120.631 - Suspension or termination of Pool Assembler.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Suspension or termination of Pool Assembler. 120.631 Section 120.631 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Secondary Market Pool Assemblers § 120.631 Suspension or termination of Pool Assembler. (a...

Estimation of heat transfer and heat source in a molten pool

Energy Technology Data Exchange (ETDEWEB)

Yun, J.I.; Suh, K.Y.; Kang, C.S. [Seoul National Univ., Dept. of Nuclear Engineering (Korea, Republic of)

2001-07-01

Heat transfer and fluid flow in a molten pool are influenced by internal volumetric heat generated from the radioactive decay of fission product species retained in the pool. The pool superheat is determined based on the overall energy balance that equates the heat production rate to the heat loss rate. Decay heat of fission products in the pool was estimated by product of the mass concentration and energy conversion factor of each fission product. For the calculation of heat generation rate in the pool, twenty-nine (29) elements were chosen and classified by their chemical properties. The mass concentration of a fission product is obtained from released fraction and the tabular output of the ORIGEN 2 code. The initial core and pool inventories at each time can also be estimated using ORIGEN 2. The released fraction of each fission product is calculated based on the bubble dynamics and mass transport. Numerical analysis was performed for the TMI-2 accident. The pool is assumed to be a partially filled hemispherical geometry, 1.45 m in radius and 32,700 kg in mass. The change of pool geometry during the numerical calculation was neglected. The peak temperature sizably decreased by about 60 K as the fission products were released from the pool. (author)

Estimation of heat transfer and heat source in a molten pool

International Nuclear Information System (INIS)

Yun, J.I.; Suh, K.Y.; Kang, C.S.

2001-01-01

Heat transfer and fluid flow in a molten pool are influenced by internal volumetric heat generated from the radioactive decay of fission product species retained in the pool. The pool superheat is determined based on the overall energy balance that equates the heat production rate to the heat loss rate. Decay heat of fission products in the pool was estimated by product of the mass concentration and energy conversion factor of each fission product. For the calculation of heat generation rate in the pool, twenty-nine (29) elements were chosen and classified by their chemical properties. The mass concentration of a fission product is obtained from released fraction and the tabular output of the ORIGEN 2 code. The initial core and pool inventories at each time can also be estimated using ORIGEN 2. The released fraction of each fission product is calculated based on the bubble dynamics and mass transport. Numerical analysis was performed for the TMI-2 accident. The pool is assumed to be a partially filled hemispherical geometry, 1.45 m in radius and 32,700 kg in mass. The change of pool geometry during the numerical calculation was neglected. The peak temperature sizably decreased by about 60 K as the fission products were released from the pool. (author)

Steam line rupture experiments with the PPOOLEX test facility

International Nuclear Information System (INIS)

Laine, J.; Puustinen, M.

2008-07-01

The results of the steam line rupture experiment series in 2007 with the scaled down PPOOLEX test facility designed and constructed at Lappeenranta University of Technology are reported. The test facility is a closed stainless steel vessel divided into two compartments, dry well and wet well. Air was blown into the dry well compartment and from there through a DN200 blowdown pipe to the condensation pool. Altogether five experiments, each consisting of several blows (tests), were carried out. The main purpose of the experiment series was to study the initial phase of a postulated steam line break accident inside a BWR containment. Specifically, thermal stratification in the dry well compartment and ejection of water plug from the blowdown pipe were of interest. In addition, the effect of counterpressure on bubble dynamics was studied. A temperature difference of approximately 15 deg. C between the upper and lower part of the dry well was measured. In the wet well gas space, a temperature difference of more than 30 deg. C was registered. These were measured during the compression period of the tests. Towards the end of the tests the temperature differences tended to disappear. To get a more detailed picture of temperature distribution in the wet well, especially close to the water level, a dense net of measurements is required in future experiments. In longer experiments, heat conduction to structures and heat losses to surroundings should also be taken into account. Ejection of water plugs from the blowdown pipe did not cause notable loads to the structures due to the suppressing effect of the dry well compartment. The maximum measured pressure pulse at the pool bottom was only 10 kPa and the maximum strain amplitude at the pool bottom rounding was negligible both in axial and circumferential direction. As the counterpressure of the system increased, but the flow rate remained the same, the maximum size of the air bubbles at the blowdown pipe outlet got smaller and

Steam line rupture experiments with the PPOOLEX test facility

Energy Technology Data Exchange (ETDEWEB)

Laine, J.; Puustinen, M. (Lappeenranta Univ. of Technology, Nuclear Safety Research Unit (Finland))

2008-07-15

The results of the steam line rupture experiment series in 2007 with the scaled down PPOOLEX test facility designed and constructed at Lappeenranta University of Technology are reported. The test facility is a closed stainless steel vessel divided into two compartments, dry well and wet well. Air was blown into the dry well compartment and from there through a DN200 blowdown pipe to the condensation pool. Altogether five experiments, each consisting of several blows (tests), were carried out. The main purpose of the experiment series was to study the initial phase of a postulated steam line break accident inside a BWR containment. Specifically, thermal stratification in the dry well compartment and ejection of water plug from the blowdown pipe were of interest. In addition, the effect of counterpressure on bubble dynamics was studied. A temperature difference of approximately 15 deg. C between the upper and lower part of the dry well was measured. In the wet well gas space, a temperature difference of more than 30 deg. C was registered. These were measured during the compression period of the tests. Towards the end of the tests the temperature differences tended to disappear. To get a more detailed picture of temperature distribution in the wet well, especially close to the water level, a dense net of measurements is required in future experiments. In longer experiments, heat conduction to structures and heat losses to surroundings should also be taken into account. Ejection of water plugs from the blowdown pipe did not cause notable loads to the structures due to the suppressing effect of the dry well compartment. The maximum measured pressure pulse at the pool bottom was only 10 kPa and the maximum strain amplitude at the pool bottom rounding was negligible both in axial and circumferential direction. As the counterpressure of the system increased, but the flow rate remained the same, the maximum size of the air bubbles at the blowdown pipe outlet got smaller and

DATA-POOL : a direct-access data base for large-scale nuclear codes

International Nuclear Information System (INIS)

Yamano, Naoki; Koyama, Kinji; Naito, Yoshitaka; Minami, Kazuyoshi.

1991-12-01

A direct-access data base DATA-POOL has been developed for large-scale nuclear codes. The data can be stored and retrieved with specifications of simple node names, by using the DATA-POOL access package written in the FORTRAN 77 language. A management utility POOL for the DATA-POOL is also provided. A typical application of the DATA-POOL is shown to the RADHEAT-V4 code system developed for performing safety analyses of radiation shielding. Many samples and error messages are also noted to apply the DATA-POOL for the other code systems. This report is provided for a manual of DATA-POOL. (author)

Seasonal variation in Chironomid emergence from coastal pools

Directory of Open Access Journals (Sweden)

Alexander T. Egan

2015-07-01

Full Text Available Understanding the phenology of emergences can be useful in determining seasonal chironomid life cycle patterns, which are often influenced by ice cover and temperature in cold climates. Lake Superior is the largest lake in North America and with a mean surface temperature of 3.9 °C influences regional climate. Coastal pools at Isle Royale, a wilderness archipelago in the northern part of the lake, occur in dense patches on low-gradient volcanic bedrock between the lakeshore and forest, creating variable microhabitats for Chironomidae. Four sites were sampled monthly from April to October, 2010. Surface-floating pupal exuviae were collected from a series of pools in two zones: a lower zone near the lake influenced by wave splash, and an upper zone near the forest and influenced by upland runoff. We used Jaccard’s and Whittaker’s diversity indexes to test community similarity across months. Temperature loggers in pools collected hourly readings for most of the study. Assemblage emergences were stable in upper pools, with significant similarity across late spring and summer months. Assemblages were seasonally variable in lower pools, with significant dissimilarity across spring, summer, and fall months. Few species in either zone were unique to spring or fall months. However, many summer species in the splash zone had a narrow emergence period occurring during calm weather following distinct increases in mean water temperature. Regardless of input of cold lake water to the lower zone, pools from both zones generally had corresponding temperature trends.

Stabilization of reactor fuel storage pool-TTP

International Nuclear Information System (INIS)

Sevigny, G.

1994-10-01

The proposed work includes evaluating standard and improved technologies an designing an integrated demonstration system to clean the water and sludge the fuel storage pools. The water released would meet drinking water standards and tritium standards. The volume of radioactive sludge would be reduced by partial separation of the sludge and radionuclides and eventual solidification of the hazardous and radioactive waste. The scope of the wo includes a survey of needs and applicable technologies, system engineering evaluation, conceptual design, detailed design, fabrication of the integrat demonstration system, and testing of the system. The survey task will locate potential specific customers within the DOE complex, and outside of the DOE complex throughout the United States, that be able to utilize the narrowly focused technology to stabilize/shutdown reactor fuel storage pools, responsible parties will be located and asked respond to a survey about their specific process requirements. Literature searches will be run through technical and scientific databases to locate technologies that may be an improvement over the standard baselined technol for cleanup of radioactively-contaminated pools. Systems engineering will provide decision analysis support for the development, evaluation, design, test functions of the treatment of pool water and sludge

Stabilization of reactor fuel storage pool-TTP

Energy Technology Data Exchange (ETDEWEB)

Sevigny, G.

1994-10-01

The proposed work includes evaluating standard and improved technologies an designing an integrated demonstration system to clean the water and sludge the fuel storage pools. The water released would meet drinking water standards and tritium standards. The volume of radioactive sludge would be reduced by partial separation of the sludge and radionuclides and eventual solidification of the hazardous and radioactive waste. The scope of the wo includes a survey of needs and applicable technologies, system engineering evaluation, conceptual design, detailed design, fabrication of the integrat demonstration system, and testing of the system. The survey task will locate potential specific customers within the DOE complex, and outside of the DOE complex throughout the United States, that be able to utilize the narrowly focused technology to stabilize/shutdown reactor fuel storage pools, responsible parties will be located and asked respond to a survey about their specific process requirements. Literature searches will be run through technical and scientific databases to locate technologies that may be an improvement over the standard baselined technol for cleanup of radioactively-contaminated pools. Systems engineering will provide decision analysis support for the development, evaluation, design, test functions of the treatment of pool water and sludge.

Sodium/water pool-deposit bed model of the CONACS code

International Nuclear Information System (INIS)

Peak, R.D.

1983-01-01

A new Pool-Bed model of the CONACS (Containment Analysis Code System) code represents a major advance over the pool models of other containment analysis code (NABE code of France, CEDAN code of Japan and CACECO and CONTAIN codes of the United States). This new model advances pool-bed modeling because of the number of significant materials and processes which are included with appropriate rigor. This CONACS pool-bed model maintains material balances for eight chemical species (C, H 2 O, Na, NaH, Na 2 O, Na 2 O 2 , Na 2 CO 3 and NaOH) that collect in the stationary liquid pool on the floor and in the desposit bed on the elevated shelf of the standard CONACS analysis cell

Natural convection heat transfer in the molten metal pool

International Nuclear Information System (INIS)

Park, R.J.; Kim, S.B.; Kim, H.D.; Choi, S.M.

1997-01-01

Analytical studies using the FLOW-3D computer program have been performed on natural convection heat transfer of a high density molten metal pool, in order to evaluate the coolability of the corium pool. The FLOW-3D results on the temperature distribution and the heat transfer rate in the molten metal pool region have been compared and evaluated with the experimental data. The FLOW-3D results have shown that the developed natural convection flow contributes to the solidified crust formation of the high density molten metal pool. The present FLOW-3D results, on the relationship between the Nusselt number and the Rayleigh number in the molten metal pool region, are more similar to the calculated results of Globe and Dropkin's correlation than any others. The natural convection heat transfer in the low aspect ratio case is more substantial than that in the high aspect ratio case. The FLOW-3D results, on the temperature profile and on the heat transfer rate in the molten metal pool region, are very similar to the experimental data. The heat transfer rate of the internal heat generation case is higher than that of the bottom heating case at the same heat supply condition. (author)

Mathematical-programming approaches to test item pool design

NARCIS (Netherlands)

Veldkamp, Bernard P.; van der Linden, Willem J.; Ariel, A.

2002-01-01

This paper presents an approach to item pool design that has the potential to improve on the quality of current item pools in educational and psychological testing andhence to increase both measurement precision and validity. The approach consists of the application of mathematical programming

Horizontal above-rack pool storage

International Nuclear Information System (INIS)

Moscardini, R.L.

1993-08-01

This report describes a unique method for storing spent, six year out of core, fuel at a prototypical PWR nuclear power station. The study describes a conceptual design, with favorable structural, thermal and criticality technical evaluations. However, economic considerations and licensing risks are judged to be less favorable. The concept study prescribes a fuel over fuel arrangement in an existing Spent Fuel Pool (SFP) with full maintenance of ALARA principles. This concept study is specific to a prototypical pool design, but may easily be projected to other nuclear facilities with other SFP conditions. For the prototypical PWR, the conceptual fuel bridge design will store over 200 additional fuel assemblies without significant facility modifications and for an indefinite time period

Pool swell sub-scale testing and code comparison

International Nuclear Information System (INIS)

Elisson, K.

1981-01-01

The main objective of the experiment was to investigate the pool swell dynamics in general and the forces on the lowered central part of the diaphragm between drywell and wetwell in particular. Apart from the high speed camera pressure transducers and strain gauges were used to monitor the transient. Data was recorded on a 14 channel FM recorder and then digitalised and plotted. In total more than one hundred tests were performed including parametric variations of for example geometry, break flow, initial drywell pressure and initial water level. In parallel to this experiment pool swell calculations have been performed with the computer codes COPTA and STEALTH. COPTA which is a lumped mass code for pressure suppression containment analysis has a slug pool swell mode. STEALTH which is a general purpose lagrangian hydrodynamics code has been used in a 2-D axisymmetric version. The STEALTH code has been used to calculate the radial variations in the vertical displacement and velocity of the pool surface and to predict the load on the lowered central part of the diaphragm. A comparison between the calculations and the experimental data indicates that both codes are sufficiently correct in their description of the pool swell transient. (orig.)

Laser sintering of metal powders on top of sintered layers under multiple-line laser scanning

International Nuclear Information System (INIS)

Xiao Bin; Zhang Yuwen

2007-01-01

A three-dimensional numerical model for multiple-line sintering of loose powders on top of multiple sintered layers under the irradiation of a moving Gaussian laser beam is carried out. The overlaps between vertically deposited layers and adjacent lines which strengthen bonding are taken into account. The energy equation is formulated using the temperature transforming model and solved by the finite volume method. The effects of the number of the existing sintered layers, porosity and initial temperature coupled with the optimal combination laser intensity and scanning velocity are presented. The results show that the liquid pool moves slightly towards the negative scanning direction and the shape of the liquid pool becomes shallower with higher scanning velocity. A higher laser intensity is needed to achieve the required overlaps when the number of the existing sintered layers increases. Increasing porosity or initial temperature enhances the sintering process and thus less intensity is needed for the overlap requirement

Observations of Cold Pool Properties during GoAmazon2014/5

Science.gov (United States)

Mayne, S. L.; Schumacher, C.; MacDonald, L.; Turner, D. D.

2017-12-01

Convectively generated cold pools are instrumental in both the development of the sub-cloud layer and the organization of deep convection. Despite this, analyses of cold pools in the tropics are constrained by a lack of observational data; insight into the phenomena therefore relies heavily on numerical models. GoAmazon2014/5, a 2-year DOE-sponsored field campaign centered on Manacapuru, Brazil in the central Amazon, provides a unique opportunity to characterize tropical cold pools and allows for the comparison of observational data with theoretical results from model cold pool simulations and parameterizations. This investigation analyzes radar, disdrometer, and profiler measurements at the DOE mobile facility site to study tropical cold pool characteristics. The Brazilian military (SIPAM) operational S-band radar in Manaus is used to provide a broad context of convective systems, while measurements from Parsivel disdrometers are used to assess drop-size distributions (DSDs) at the surface. A unique aspect of this research is the use of the Atmospheric Emitted Radiance Interferometer (AERI) instrument, which utilizes down-welling IR measurements to obtain vertical profiles of thermodynamic quantities such as temperature and water vapor in the lowest few km of the atmosphere. Combined with surface observations and sounding data, these datasets will result in a thorough investigation of the horizontal and vertical characteristics of cold pools over the tropical rain forest. Preliminary analyses of 20 events reveal a mean cold pool height of 220 m and a mean radius of approximately 8.5 km. The average cold pool experienced a temperature (specific humidity) decrease of approximately 1 K (0.4 g/kg) at the surface. The temperature decrease is consistent with modeling studies and limited observations from previous studies over the tropics. The small decrease in specific humidity is attributed to the high moisture content within the cold pools. AERI retrievals of

Lace-Espana experimental programme on the retention of aerosols in water pools

Energy Technology Data Exchange (ETDEWEB)

Marcos, M. J.; Gomez, F. J.; Melches, I.; Martin, M.; Lopez, M.

1994-07-01

A matrix of eleven experiments on aerosol retention behaviour in submerged beds and suppression pools in water- cooled reactors under severe accident conditions has been performed, for these experiments, an intermediate scales, multi-purpose facility was set up at CIEMAT (Madrid). The facility includes various systems: aerosol generation (Csl), mixing section, injection line and pool-vessel (8 m{sup 3} ), as well as the corresponding aerosol instrumentation and a process control and data acquisition system. Some parameters have been varied in order to study their influence in the DF: steam/noncondensable ratio in the accidental mixture (0.1 to 0.9), particle size, flow rate (two regimes: bubble and jet) and injector geometry (mono orifice and multi orifice). On the other hand, some parameters have been kept constant along the experiments; pool geometry (diameter, water level), water temperature, pressure in the atmosphere above the water, submergence, injection temperature and injection time. A rapid decrease in the DF is observed as the proportion of particles measuring less than 1 {mu}m increases. Retention decreases in the case of smaller particles and considerably higher in the case of larger particles. It has been also possible to observe the influence of the injected steam fraction. Experiments with greater fraction than the saturation fraction have greater DF than those ones with smaller fractions. The jet regime with horizontal injection and the multi orifice geometry would appear to show a somewhat higher capacity of retention than those in the bubble regime under similar conditions. It would be necessary to confirm this greater capacity for retention by means of additional experimental data. This work, performed by the LACE-Espana Consortium, has been carried out in the frame of the European Commissions Shared Cost Action Programme on Reactor Safety 1988-91 on a contractual basis. (Author)18 refs.

Lace-Espana experimental programme on the retention of aerosols in water pools

International Nuclear Information System (INIS)

Marcos, M. J.; Gomez, F. J.; Melches, I.; Martin, M.; Lopez, M.

1994-01-01

A matrix of eleven experiments on aerosol retention behaviour in submerged beds and suppression pools in water- cooled reactors under severe accident conditions has been performed, for these experiments, an intermediate scales, multi-purpose facility was set up at CIEMAT (Madrid). The facility includes various systems: aerosol generation (Csl), mixing section, injection line and pool-vessel (8 m 3 ), as well as the corresponding aerosol instrumentation and a process control and data acquisition system. Some parameters have been varied in order to study their influence in the DF: steam/noncondensable ratio in the accidental mixture (0.1 to 0.9), particle size, flow rate (two regimes: bubble and jet) and injector geometry (mono orifice and multi orifice). On the other hand, some parameters have been kept constant along the experiments; pool geometry (diameter, water level), water temperature, pressure in the atmosphere above the water, submergence, injection temperature and injection time. A rapid decrease in the DF is observed as the proportion of particles measuring less than 1 μm increases. Retention decreases in the case of smaller particles and considerably higher in the case of larger particles. It has been also possible to observe the influence of the injected steam fraction. Experiments with greater fraction than the saturation fraction have greater DF than those ones with smaller fractions. The jet regime with horizontal injection and the multi orifice geometry would appear to show a somewhat higher capacity of retention than those in the bubble regime under similar conditions. It would be necessary to confirm this greater capacity for retention by means of additional experimental data. This work, performed by the LACE-Espana Consortium, has been carried out in the frame of the European Commissions Shared Cost Action Programme on Reactor Safety 1988-91 on a contractual basis. (Author)18 refs

Lace-Espana experimental programme on the retention of aerosols in water pools

International Nuclear Information System (INIS)

Marcos Crespo, M.J.; Gomez; Moreno, F. J.; Melches Serrano, I.; Martin Espigares, M.; Lopez Jimenez, J.

1994-01-01

A matrix of eleven experiments on aerosol retention behaviour in submerged beds and suppression pools in water-cooled reactors under severe accident conditions has been performed, for these experiments, an intermediate scale, multi-purpose facility was set up at CIEMAT (Madrid). The facility includes various systems: aerosol ageneration (CsI), mixing section, injection line and pool-vessel (8 m''3), as well as the corresponding aerosol instrumentation and a process control and data acquisition system. Some parameters have been varied in order to study their influence in the DF: steam/noncondensable ratio in the accidental mixture (0,1 to 0.9) particle size, flow rate (two regimes: bubble and jet) and injector geometry (monoorifice and multiorifice). On the other hand, some parameters have been kept constant along the experiments; pool geometry (diameter, water level), water temperature, pressure in the atmosphere above the water, submergence, injection temperature and injection time. A Rapid decrease in the DF is observed as the proportion of particles measuring les than 1 mum increases. Retention decreases in the case of smaller particles and considerably higher in the case of larger particles. It has been also possible to observe the influence of the injected steam fraction. Experiments with greater fraction than the saturation fraction have greater DF than those ones with smaller fractions. The jet regime with horizontal injection and the multiorifice geometry would appear to show a somewhat higher capacity of retention than those in the bubble regime under similar conditions. It would be necessary to confirm this greater capacity for retention by means of additional experimental data. This work, performed by the LACE-Espana Consortium, has been carried out in the frame of the European Commission's Shared Cost Action Programme on Reactor Safety 1988-91 on a contractual basis

Sustainability of common pool resources.

Science.gov (United States)

Timilsina, Raja Rajendra; Kotani, Koji; Kamijo, Yoshio

2017-01-01

Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as "capitalism," affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepalese areas: (i) rural (non-capitalistic) and (ii) urban (capitalistic) areas. We find that a proportion of prosocial individuals in urban areas is lower than that in rural areas, and urban residents deplete resources more quickly than rural residents. The composition of proself and prosocial individuals in a group and the degree of capitalism are crucial in that an increase in prosocial members in a group and the rural dummy positively affect resource sustainability by 65% and 63%, respectively. Overall, this paper shows that when societies move toward more capitalistic environments, the sustainability of common pool resources tends to decrease with the changes in individual preferences, social norms, customs and views to others through human interactions. This result implies that individuals may be losing their coordination abilities for social dilemmas of resource sustainability in capitalistic societies.

Single-Track Melt-Pool Measurements and Microstructures in Inconel 625

Science.gov (United States)

Ghosh, Supriyo; Ma, Li; Levine, Lyle E.; Ricker, Richard E.; Stoudt, Mark R.; Heigel, Jarred C.; Guyer, Jonathan E.

2018-02-01

We use single-track laser melting experiments and simulations on Inconel 625 to estimate the dimensions and microstructure of the resulting melt pool. Our work is based on a design-of-experiments approach which uses multiple laser power and scan speed combinations. Single-track experiments generated melt pools of certain dimensions that showed reasonable agreement with our finite-element calculations. Phase-field simulations were used to predict the size and segregation of the cellular microstructure that formed along the melt-pool boundaries for the solidification conditions that changed as a function of melt-pool dimensions.

Single-Track Melt-Pool Measurements and Microstructures in Inconel 625

Science.gov (United States)

Ghosh, Supriyo; Ma, Li; Levine, Lyle E.; Ricker, Richard E.; Stoudt, Mark R.; Heigel, Jarred C.; Guyer, Jonathan E.

2018-06-01

We use single-track laser melting experiments and simulations on Inconel 625 to estimate the dimensions and microstructure of the resulting melt pool. Our work is based on a design-of-experiments approach which uses multiple laser power and scan speed combinations. Single-track experiments generated melt pools of certain dimensions that showed reasonable agreement with our finite-element calculations. Phase-field simulations were used to predict the size and segregation of the cellular microstructure that formed along the melt-pool boundaries for the solidification conditions that changed as a function of melt-pool dimensions.

3-dimensional thermohydraulic analysis of KALIMER reactor pool during unprotected accidents

Energy Technology Data Exchange (ETDEWEB)

Lee, Yong Bum; Hahn Do Hee

2003-01-01

During a normal reactor scram, the heat generation is reduced almost instantaneously while the coolant flow rate follows the pump coastdown. This mismatch between power and flow results in a situation where the core flow entering the hot pool is at a lower temperature than the temperature of the bulk pool sodium. This temperature difference leads to thermal stratification. Thermal stratification can occur in the hot pool region if the entering coolant is colder than the existing hot pool coolant and the flow momentum is not large enough to overcome the negative buoyancy force. Since the fluid of hot pool enters IHXs, the temperature distribution of hot pool can alter the overall system response. Hence, it is necessary to predict the pool coolant temperature distribution with sufficient accuracy to determine the inlet temperature conditions for the IHXs and its contribution to the net buoyancy head. Therefore, two-dimensional hot pool thermohydraulic model named HP2D has been developed. In this report code-to-code comparison analysis between HP2D and COMMIX-1AR/P has been performed in the case of steady-state and UTOP.

Preliminary Calculation on a Spent Fuel Pool Accident using GOTHIC

Energy Technology Data Exchange (ETDEWEB)

Park, Jaehwan; Choi, Yu Jung; Hong, Tae Hyub; Kim, Hyeong-Taek [KHNP-CRI, Daejeon (Korea, Republic of)

2015-10-15

The probability of an accident happening at the spent fuel pool was believed to be quite low until the 2011 Fukushima accident occurred. Notably, large amount of spent fuel are normally stored in the spent fuel pool for a long time compared to the amount of fuel in the reactor core and the total heat released from the spent fuel is high enough to boil the water of the spent fuel pool when the cooling system does not operate. In addition, the enrichment and the burnup of the fuel have both increased in the past decade and heat generation from the spent fuel thereby has also increased. The failure of the cooling system at the spent fuel pool (hereafter, a loss-of-cooling accident) is one of the principal hypothetical causes of an accident that could occur at the spent fuel pool. In this paper, the preliminary calculation of a loss-of-cooling accident was performed. In this paper, the preliminary calculation of a loss-of cooling accident was performed with GOTHIC. The calculation results show boiling away of water in the spent fuel pool due to the loss-of-cooling accident and similar thermal performance of the spent fuel pool with previous research results.

Study on velocity distribution in a pool by submersible mixers

International Nuclear Information System (INIS)

Tian, F; Shi, W D; Lu, X N; Chen, B; Jiang, H

2012-01-01

To study the distribution of submersible mixers and agitating effect in the sewage treatment pool, Pro/E software was utilized to build the three-dimensional model. Then, the large-scale computational fluid dynamics software FLUENT6.3 was used. ICEM software was used to build unstructured grid of sewage treatment pool. After that, the sewage treatment pool was numerically simulated by dynamic coordinate system technology and RNG k-ε turbulent model and PIOS algorithm. The macro fluid field and each section velocity flow field distribution were analyzed to observe the efficiency of each submersible mixer. The average velocity and mixing area in the sewage pool were studied simultaneously. Results show that: the preferred project B, two submersible mixers speed is 980 r/min, and setting angles are all 30°. Fluid mixing area in the pool has reached more than 95%. Under the action of two mixers, the fluid in the sewage pool form a continuous circulating water flow. The fluid is mixed adequately and average velocity of fluid in the pool is at around 0.241m/s, which agreed with the work requirements. Consequently it can provide a reference basis for practical engineering application of submersible mixers by using this method.

Pool Boiling CHF in Inclined Narrow Annuli

International Nuclear Information System (INIS)

Kang, Myeong Gie

2010-01-01

Pool boiling heat transfer has been studied extensively since it is frequently encountered in various heat transfer equipment. Recently, it has been widely investigated in nuclear power plants for application to the advanced light water reactors designs. Through the review on the published results it can be concluded that knowledge on the combined effects of the surface orientation and a confined space on pool boiling heat transfer is of great practical importance and also of great academic interest. Fujita et al. investigated pool boiling heat transfer, from boiling inception to the critical heat flux (CHF, q' CHF ), in a confined narrow space between heated and unheated parallel rectangular plates. They identified that both the confined space and the surface orientation changed heat transfer much. Kim and Suh changed the surface orientation angles of a downward heating rectangular channel having a narrow gap from the downward-facing position (180 .deg.) to the vertical position (90 .deg.). They observed that the CHF generally decreased as the inclination angle (θ ) increased. Yao and Chang studied pool boiling heat transfer in a confined heat transfer for vertical narrow annuli with closed bottoms. They observed that when the gap size ( s ) of the annulus was decreased the effect of space confinement to boiling heat transfer increased. The CHF was occurred at much lower value for the confined space comparing to the unconfined pool boiling. Pool boiling heat transfer in narrow horizontal annular crevices was studied by Hung and Yao. They concluded that the CHF decreased with decreasing gap size of the annuli and described the importance of the thin film evaporation to explain the lower CHF of narrow crevices. The effect of the inclination angle on the CHF on countercurrent boiling in an inclined uniformly heated tube with closed bottoms was also studied by Liu et al. They concluded that the CHF reduced with the inclination angle decrease. A study was carried out

Microbial diversity in acidic thermal pools in the Uzon Caldera, Kamchatka.

Science.gov (United States)

Mardanov, Andrey V; Gumerov, Vadim M; Beletsky, Alexey V; Ravin, Nikolai V

2018-01-01

Microbial communities of four acidic thermal pools in the Uzon Caldera, Kamchatka, Russia, were studied using amplification and pyrosequencing of 16S rRNA gene fragments. The sites differed in temperature and pH: 1805 (60 °C, pH 3.7), 1810 (90 °C, pH 4.1), 1818 (80 °C, pH 3.5), and 1807 (86 °C, pH 5.6). Archaea of the order Sulfolobales were present among the dominant groups in all four pools. Acidilobales dominated in pool 1818 but were a minor fraction at the higher temperature in pool 1810. Uncultivated Archaea of the Hot Thaumarchaeota-related clade were present in significant quantities in pools 1805 and 1807, but they were not abundant in pools 1810 and 1818, where high temperatures were combined with low pH. Nanoarchaeota were present in all pools, but were more abundant in pools 1810 and 1818. A similar abundance pattern was observed for Halobacteriales. Thermophilic Bacteria were less diverse and were mostly represented by aerobic hydrogen- and sulfur-oxidizers of the phylum Aquificae and sulfur-oxidising Proteobacteria of the genus Acidithiobacillus. Thus we showed that extremely acidic hot pools contain diverse microbial communities comprising different metabolic groups of prokaryotes, including putative lithoautotrophs using energy sources of volcanic origin, and various facultative and obligate heterotrophs.

Planar measurements of soot volume fraction and OH in a JP-8 pool fire

Energy Technology Data Exchange (ETDEWEB)

Henriksen, Tara L.; Ring, Terry A.; Eddings, Eric G. [Department of Chemical Engineering, University of Utah, Salt Lake City, UT 84112 (United States); Nathan, Graham J. [School of Mechanical Engineering, University of Adelaide, SA 5005 (Australia); Alwahabi, Zeyad T.; Qamar, Nader [School of Chemical Engineering, University of Adelaide, SA 5005 (Australia)

2009-07-15

The simultaneous measurement of soot volume fraction by laser induced incandescence (LII) and qualitative imaging of OH by laser induced fluorescence (LIF) was performed in a JP-8 pool fire contained in a 152 mm diameter pan. Line of sight extinction was used to calibrate the LII system in a laminar flame, and to provide an independent method of measuring average soot volume fraction in the turbulent flame. The presence of soot in the turbulent flame was found to be approximately 50% probable, resulting in high levels of optical extinction, which increased slightly through the flame from approximately 30% near the base, to approximately 50% at the tip. This high soot loading pushes both techniques toward their detection limit. Nevertheless, useful accuracy was obtained, with the LII measurement of apparent extinction in the turbulent flame being approximately 21% lower than a direct measurement, consistent with the influence of signal trapping. The axial and radial distributions of soot volume fraction are presented, along with PDFs of volume fraction, and new insight into the behavior of soot sheets in pool fires are sought from the simultaneous measurements of OH and LII. (author)

Experimental investigation of particulate debris spreading in a pool

Energy Technology Data Exchange (ETDEWEB)

Konovalenko, A., E-mail: kono@kth.se [Division of Nuclear Power Safety, Royal Institute of Technology (KTH) , Roslagstullsbacken 21, Stockholm 106 91 (Sweden); Basso, S., E-mail: simoneb@kth.se [Division of Nuclear Power Safety, Royal Institute of Technology (KTH) , Roslagstullsbacken 21, Stockholm 106 91 (Sweden); Kudinov, P., E-mail: pkudinov@kth.se [Division of Nuclear Power Safety, Royal Institute of Technology (KTH) , Roslagstullsbacken 21, Stockholm 106 91 (Sweden); Yakush, S.E., E-mail: yakush@ipmnet.ru [Institute for Problems in Mechanics of the Russian Academy of Sciences, Ave. Vernadskogo 101 Bldg 1, Moscow 119526 (Russian Federation)

2016-02-15

Termination of severe accident progression by core debris cooling in a deep pool of water under reactor vessel is considered in several designs of light water reactors. However, success of this accident mitigation strategy is contingent upon the effectiveness of heat removal by natural circulation from the debris bed. It is assumed that a porous bed will be formed in the pool in the process of core melt fragmentation and quenching. Debris bed coolability depends on its properties and system conditions. The properties of the bed, including its geometry are the outcomes of the debris bed formation process. Spreading of the debris particles in the pool by two-phase turbulent flows induced by the heat generated in the bed can affect the shape of the bed and thus influence its coolability. The goal of this work is to provide experimental data on spreading of solid particles in the pool by large-scale two-phase flow. The aim is to provide data necessary for understanding of separate effects and for development and validation of models and codes. Validated codes can be then used for prediction of debris bed formation under prototypic severe accident conditions. In PDS-P (Particulate Debris Spreading in the Pool) experiments, air injection at the bottom of the test section is employed as a means to create large-scale flow in the pool in isothermal conditions. The test section is a rectangular tank with a 2D slice geometry, it has fixed width (72 mm), adjustable length (up to 1.5 m) and allows water filling to the depth of up to 1 m. Variable pool length and depth allows studying two-phase circulating flows of different characteristic sizes and patterns. The average void fraction in the pool is determined by video recording and subsequent image processing. Particles are supplied from the top of the facility above the water surface. Results of several series of PDS-P experiments are reported in this paper. The influence of the gas flow rate, pool dimensions, particle density

Effect of pool rotation on three-dimensional flow in a shallow annular pool of silicon melt with bidirectional temperature gradients

Energy Technology Data Exchange (ETDEWEB)

Zhang, Quan-Zhuang; Peng, Lan; Liu, Jia [Key Laboratory of Low-grade Energy Utilization Technologies and Systems of Ministry of Education, College of Power Engineering, Chongqing University, Chongqing, 400044 (China); Wang, Fei, E-mail: penglan@cqu.edu.cn [Chongqing Special Equipment Inspection and Research Institute, Chongqing, 401121 (China)

2016-08-15

In order to understand the effect of pool rotation on silicon melt flow with the bidirectional temperature gradients, we conducted a series of unsteady three-dimensional (3D) numerical simulations in a shallow annular pool. The bidirectional temperature gradients are produced by the temperature difference between outer and inner walls as well as a constant heat flux at the bottom. Results show that when Marangoni number is small, a 3D steady flow is common without pool rotation. But it bifurcates to a 3D oscillatory flow at a low rotation Reynolds number. Subsequently, the flow becomes steady and axisymmetric at a high rotation Reynolds number. When the Marangoni number is large, pool rotation can effectively suppress the temperature fluctuation on the free surface, meanwhile, it improves the flow stability. The critical heat flux density diagrams are mapped, and the effects of radial and vertical temperature gradients on the flow are discussed. Additionally, the transition process from the flow dominated by the radial temperature gradient to the one dominated by the vertical temperature gradient is presented. (paper)

13 CFR 120.1709 - Transfers of Pool Certificates.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Transfers of Pool Certificates. 120.1709 Section 120.1709 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1709...

13 CFR 120.1714 - Seller's Pool Loan servicing.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Seller's Pool Loan servicing. 120.1714 Section 120.1714 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1714 Seller...

13 CFR 120.1715 - Seller's Pool Loan liquidation.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Seller's Pool Loan liquidation. 120.1715 Section 120.1715 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1715 Seller...

13 CFR 120.1713 - Seller's Pool Loan origination.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Seller's Pool Loan origination. 120.1713 Section 120.1713 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1713 Seller...

13 CFR 120.1717 - Seller's Pool Loan deferments.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Seller's Pool Loan deferments. 120.1717 Section 120.1717 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1717 Seller...

25 years later, US abortion war still drags on.

Science.gov (United States)

Rovner, J

1998-01-31

In the 25 years since the US Supreme Court's landmark Roe vs. Wade decision legalizing abortion, activists on both sides of the issue have drawn further apart as they have vied for the support of the majority of US voters who express ambivalence towards the law. These voters believe that abortion may be murder but that it must be legal. The Roe vs. Wade anniversary has sparked new legislative priorities on both sides. Abortion-rights activists will seek legislation that attempts to decrease the need for abortion by increasing funding for family planning services in the US and abroad, supporting funding for contraceptive research, and requiring health insurers to pay for contraceptives. Abortion opponents will continue to press for "partial birth" abortion bans and will support efforts to make it a federal crime for an adult to transport a minor across state lines to evade state parental notification or consent laws.

The pool chlorine hypothesis and asthma among boys.

LENUS (Irish Health Repository)

Cotter, A

2012-01-31

Swimming pool sanitation has largely been concerned with the microbiological quality of pool water, which is normally treated using a number of chlorine products. Recent studies have pointed to the potential hazards of chlorine by-products to the respiratory epithelium, particularly in indoor, poorly ventilated, pools. The aim of our study was to elucidate whether chronic exposure to indoor chlorinated swimming pools was associated with an increased likelihood of the development of asthma in boys. METHODS: The subjects were boys aged between 6 and 12 years. Data was collected by means of parental responses to a standardized asthma questionnaire (ISAAC: International Study of Asthma and Allergies in Childhood), supplemented with additional questions regarding frequency of attendance, number of years attendance, whether the child is a swimming team member. The questionnaire return rate was 71\\/% (n = 121). 23 boys were excluded on the basis that they had asthma before they started swimming (n = 97). There was a significant association between number of years a boy had been swimming and the likelihood of wheezing in the last 12 months (p = 0.009; OR = 1.351; 95% CI = 1.077-1.693) and diagnosed asthma (p = 0.046; OR = 1.299; 95% CI = 1.004-1.506). The greater the number the number of years a boy had been attending an indoor, chlorinated pool, the greater the likelihood of wheezing in the last 12 months or "had asthma". Age, parental smoking habits and being a swimming team member had no association with any of the asthma variables examined. Swimming pool attendance may be a risk factor in asthma in boys.

Characterization of selection effects on broiler lines using DNA fingerprinting

Directory of Open Access Journals (Sweden)

GS Schmidt

2003-05-01

Full Text Available The objective of this study was to evaluate the effect of selection for body weight on the genetic variability and diversity in broiler lines. Two paternal broiler lines (LL and LLc were used. LL line was selected for 12 generations for growth and carcass and reproduction characteristics. The LLc line was established from LL line in 1985 and mated at random. Blood samples from six chickens per line were collected and used for molecular analysis. Also, a DNA pool was made for each line to compare effects between lines. Data were analyzed considering the collected information on the presence or absence of DNA bands. Band sharing scores were calculated using the DICE coefficient. The pattern of the 21 most representative bands was used. DNA fingerprinting (DFP showed 90.48 % of polymorphism bands for both lines. Difference between lines was not due to the presence or absence of bands, but to the frequency of such bands in each genotype. Considering that both lines had the same genetic background, changes on band frequency were probably due to selection. Selection for body weight had an effect on the band frequency as evaluated by DFP, and for this reason this technique could be used as a tool in the selection process. Results also suggest that bands 4, 5 and 19 were linked to body weight traits, and bands 9, 10, 12, 13 and 21 were linked to reproductive traits such as egg production.

Use of Aria to simulate laser weld pool dynamics for neutron generator production.

Energy Technology Data Exchange (ETDEWEB)

Noble, David R.; Notz, Patrick K.; Martinez, Mario J.; Kraynik, Andrew Michael

2007-09-01

This report documents the results for the FY07 ASC Integrated Codes Level 2 Milestone number 2354. The description for this milestone is, 'Demonstrate level set free surface tracking capabilities in ARIA to simulate the dynamics of the formation and time evolution of a weld pool in laser welding applications for neutron generator production'. The specialized boundary conditions and material properties for the laser welding application were implemented and verified by comparison with existing, two-dimensional applications. Analyses of stationary spot welds and traveling line welds were performed and the accuracy of the three-dimensional (3D) level set algorithm is assessed by comparison with 3D moving mesh calculations.

Evaporation rate measurement in the pool of IEAR-1 reactor

International Nuclear Information System (INIS)

Torres, Walmir Maximo; Cegalla, Miriam A.; Baptista Filho, Benedito Dias

2000-01-01

The surface water evaporation in pool type reactors affects the ventilation system operation and the ambient conditions and dose rates in the operation room. This paper shows the results of evaporation rate experiment in the pool of IEA-R1 research reactor. The experiment is based on the demineralized water mass variation inside cylindrical metallic recipients during a time interval. Other parameters were measured, such as: barometric pressure, relative humidity, environmental temperature, water temperature inside the recipients and water temperature in the reactor pool. The pool level variation due to water contraction/expansion was calculated. (author)

Phase analysis in gated blood pool tomography

International Nuclear Information System (INIS)

Nakajima, Kenichi; Bunko, Hisashi; Tada, Akira; Taki, Junichi; Nanbu, Ichiro

1984-01-01

Phase analysis of gated blood pool study has been applied to detect the site of accessory conduction pathway (ACP) in the Wolff-Parkinson-White (WPW) syndrome; however, there was a limitation to detect the precise location of ACP by phase analysis alone. In this study, we applied phase analysis to gated blood pool tomography using seven pin hole tomography (7PT) and gated emission computed tomography (GECT) in 21 patients with WPW syndrome and 3 normal subjects. In 17 patients, the sites of ACPs were confirmed by epicardial mapping and the result of the surgical division of ACP. In 7PT, the site of ACP grossly agreed to the abnormal initial phase in phase image in 5 out of 6 patients with left cardiac type. In GECT, phase images were generated in short axial, vertical and horizontal long axial sections. In 8 out of 9 patients, the site of ACP was correctly identified by phase images, and in a patient who had two ACPs, initial phase corresponded to one of the two locations. Phase analysis of gated blood pool tomography has advantages for avoiding overlap of blood pools and for estimating three-dimensional propagation of the contraction, and can be a good adjunctive method in patients with WPW syndrome. (author)

SBWR PCCS vent phenomena and suppression pool mixing

Energy Technology Data Exchange (ETDEWEB)

Coddington, P. [Thermal-Hydraulics Lab., Paul Scherrer Institute, Villigen (Switzerland); Andreani, M. [Nuclear Engineering Lab., Swiss Federal Institute of Technology, Zurich (Switzerland)

1995-09-01

The most important phenomena influencing the effectiveness of the pressure suppression capability of the water pool within the Wetwell compartment of the SBWR Containment, during the period of Passive Containment Cooling System (PCCS) venting, have been critically reviewed. In addition, calculations have been carried-out to determine the condensation of the vented steam and the distribution of the energy deposited in the liquid pool. It has been found that a large contribution to the vapour suppression is due to condensation inside the vent pipe. The condensation rate of the steam inside the bubbles, produced at the vent exit, during their rise to the surface, may however be rather low, because of the large size bubbles. This can lead to vapour channelling to the Wetwell gas space. The above comments are likely to be ameliorated if the vent exit is a distributed source or sparger. Due to the large water flow rates within the {open_quotes}bubbly two-phase plume{close_quotes} generated by the gas injection, the water in the pool above the vent exit is likely to be heated nearly isothermally (perfect mixing). The effect of the suppression pool walls would be to enhance the recirculation and, consequently to promote mixing. The large size of the bubbles therein and of the walls on pool mixing are the most severe difficulties in extrapolating the results from scaled experiments to prototypical conditions.

The management of the Spend Fuel Pool Water Quality (1996-2007)

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae Hwan; Lee, Eui Gyu; Choi, Ho Young; Choi, Mun Jo; Kim, Hyung Wook; Lee, Mun; Lee, Choong Sung; Hur, Soon Ock; Ahn, Guk Hun

2008-12-15

The water quality management of spent fuel storage pool water quality in HANARO is important to prevent the corrosion of nuclear fuel and reactor structure material. The condition of the spent fuel storage pool water has been monitored by measuring the electrical conductivity of the spent fuel storage pool purification system and pH periodically. The status of the spent fuel storage pool water quality management was investigated by using the measured data. taken from 1996 to 2007. In general, the electrical conductivity of the spent fuel storage pool water have been managed within 1 {mu}S/cm which is an operation target of HANARO.

Biomass and carbon pools of disturbed riparian forests

Science.gov (United States)

Laura A. B. Giese; W. M. Aust; Randall K. Kolka; Carl C. Trettin

2003-01-01

Quantification of carbon pools as affected by forest age/development can facilitate riparian restoration and increase awareness of the potential for forests to sequester global carbon. Riparian forest biomass and carbon pools were quantified for four riparian forests representing different seral stages in the South Carolina Upper Coastal Plain. Three of the riparian...

Solar collectors for swimming pools still going strong

Energy Technology Data Exchange (ETDEWEB)

1975-01-01

According to the opinion of the experts, solar energy heating may be technically 'mature' but the profitability is by no means that far. However, solar systems are a good alternative for heating the water in swimming pools. Four solar collector systems developed by different firms to heat swimming pools, including prices, are presented.

Lip and tooth injuries at public swimming pools in Austria.

Science.gov (United States)

Lechner, Katharina; Connert, Thomas; Kühl, Sebastian; Filippi, Andreas

2017-06-01

There is an increased risk of orofacial injuries in swimming pool facilities. Nevertheless, only a few studies have addressed this issue. The aim of this study was to identify the frequency of lip and tooth injuries at public swimming pools in Austria. A further aim was to examine which gender and age groups were affected, where and why these injuries occurred, and whether pool attendants had sufficient knowledge of dental first-aid measures. A total of 764 pool attendants in Austria were contacted by telephone and 689 participated in the study (90.2%). The attendants were interviewed retrospectively about accident occurrences in 2014 by a standardized questionnaire. Responses to the provision of first aid and choice of storage medium for avulsed teeth were subsequently evaluated. The frequency of lip injuries was 19.0%, and tooth injuries were 11.3%. Male bathers (P < .05) and children under 12 years (P < .001) most frequently suffered injuries. The waterslide was the most common accident site. The most common cause of lip injuries was slipping on wet surfaces (39.0%), and for tooth injuries it was collisions with other persons or objects (each 28.1%). The pool attendants' responses were predominantly good or sufficient on first aid, with the exception of what storage medium to choose. Tooth rescue boxes were available in only 8.6% of all pool facilities. Orofacial injuries are a frequently occurring problem in swimming pool facilities. The pool attendants' knowledge on first-aid care of tooth injuries could still be improved. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Branchipodopsis species — specialists of ephemeral rock pools ...

African Journals Online (AJOL)

Such rock pools were studied in the Drakensberg region, in the eastern Free State and in south-eastern Botswana. Common features ... While short-range dispersal of floating eggs by overflows is common, long-range dispersal (e.g. by wind) seems to be rare and to be restricted to shallow pools with little vegetation. Limited ...

CO{sub 2} flooding performance prediction for Alberta oil pools

Energy Technology Data Exchange (ETDEWEB)

Shaw, J.C. [Adams Pearson Associates Inc., Calgary, AB (Canada); Bachu, S. [Alberta Energy and Utilities Board, Calgary, AB (Canada)

2002-06-01

An advanced technical screening program was used to successfully screen and rank a very large number of Alberta oil pools for enhanced oil recovery using carbon dioxide (CO{sub 2}) flooding. This paper is a continuation paper describing the results of using the Microsoft Excel program with VBA to estimate production forecasts for several candidate pools in Alberta. A total of 6 ranking parameters were used, including API gravity of oil, residual oil saturation, ratio between reservoir pressure and minimum miscibility pressure, reservoir temperature, net pay thickness and porosity. The screening program provides a technical ranking of approximately 8,000 Alberta pools. After compilation of the Alberta oil pools, it was determined that most of the deep carbonate oil pools are excellent candidates for CO{sub 2} miscible flooding. Other Devonian carbonate pools are also ranked as having high potential for the process. An environmental benefit of CO{sub 2} miscible flooding process is that carbon sequestration has the potential to reduce anthropogenic carbon dioxide emissions from reaching the atmosphere. Ongoing studies are currently addressing CO{sub 2} capture and transportation, making EOR technology viable for maintaining light oil production in western Canada. 11 refs., 2 tabs., 2 figs.

AE/VCE Unconfirmed Vernal Pools

Data.gov (United States)

Vermont Center for Geographic Information — This dataset is derived from a project by the Vermont Center for Ecostudies(VCE) and Arrowwood Environmental(AE) to map vernal pools throughout the state of Vermont....

AE/VCE Confirmed Vernal Pools

Data.gov (United States)

Vermont Center for Geographic Information — This dataset is derived from a project by the Vermont Center for Ecostudies(VCE) and Arrowwood Environmental(AE) to map vernal pools throughout the state of Vermont....

Energy Pooling Upconversion in Free Space and Optical Cavities

Science.gov (United States)

LaCount, Michael D.

The ability to efficiently convert the wavelength of light has value in a wide range of disciplines that include the fields of photovoltaics, plant growth, optics and medicine. The processes by which such transformations are carried out are known as upconversions and downconversions. There are several ways to up/down convert light, each with its own attributes, issues, and competing mechanisms. Most are associated with one-body or two-body processes. Three-body dynamics are also possible though, going by the names of quantum cutting (downconversion) and energy pooling (upconversion). These use virtual excited electronic states to mediate conversions as has been experimentally realized using lanthanide ions embedded in wide bandgap materials. The use of lanthanides to convert light is not ideal due to their relative scarcity, toxicity, and the limited range of light frequencies that can be absorbed and emitted. Organic molecules, on the other hand, are typically non-toxic, are made up of abundant elements, and can be designed with tailored spectral properties. At issue is whether or not they can be used to carry out efficient energy pooling, the central question to be answered in this thesis. The research presented here draws on a perturbative quantum electrodynamics framework previously established for generic energy pooling. It was used to develop a computational methodology for determining the rate of energy pooling and its competing processes. This, in turn, draws on a combination of time-dependent density functional theory, quantum electrodynamics, and perturbation theory to generate the requisite material property data. This computational model was applied to two test systems consisting of stilbene-fluorescein and hexabenzocoronene-oligothiophene. The stilbene-fluorescein system was found to have a maximum energy pooling rate efficiency (as compared to competing processes) of 17% and the hexabenzocoronene-oligothiophene system was found to have a maximum

A Double Evolutionary Pool Memetic Algorithm for Examination Timetabling Problems

Directory of Open Access Journals (Sweden)

Yu Lei

2014-01-01

Full Text Available A double evolutionary pool memetic algorithm is proposed to solve the examination timetabling problem. To improve the performance of the proposed algorithm, two evolutionary pools, that is, the main evolutionary pool and the secondary evolutionary pool, are employed. The genetic operators have been specially designed to fit the examination timetabling problem. A simplified version of the simulated annealing strategy is designed to speed the convergence of the algorithm. A clonal mechanism is introduced to preserve population diversity. Extensive experiments carried out on 12 benchmark examination timetabling instances show that the proposed algorithm is able to produce promising results for the uncapacitated examination timetabling problem.

Inferring local ecological processes amid species pool influences

DEFF Research Database (Denmark)

Lessard, Jean-Philippe; Belmaker, Jonathan; Myers, Jonathan A.

2012-01-01

studies, null models of community structure, and ecologically explicit definitions of the species pool as a means to compare predominant ecological processes among regions. By uniting concepts and tools from community ecology and macroecology, this approach might facilitate synthesis and resolve many......Resolving contingencies in community ecology requires comparative studies of local communities along broad-scale environmental gradients and in different biogeographic regions. However, comparisons of local ecological processes among regions require a synthetic understanding of how the species pool...... of potential community members influences the structure of ecological communities. Here, we outline an integrative approach for quantifying local ecological processes while explicitly accounting for species pool influences. Specifically, we highlight the utility of combining geographically replicated local...

Alcoholism Detection by Data Augmentation and Convolutional Neural Network with Stochastic Pooling.

Science.gov (United States)

Wang, Shui-Hua; Lv, Yi-Ding; Sui, Yuxiu; Liu, Shuai; Wang, Su-Jing; Zhang, Yu-Dong

2017-11-17

Alcohol use disorder (AUD) is an important brain disease. It alters the brain structure. Recently, scholars tend to use computer vision based techniques to detect AUD. We collected 235 subjects, 114 alcoholic and 121 non-alcoholic. Among the 235 image, 100 images were used as training set, and data augmentation method was used. The rest 135 images were used as test set. Further, we chose the latest powerful technique-convolutional neural network (CNN) based on convolutional layer, rectified linear unit layer, pooling layer, fully connected layer, and softmax layer. We also compared three different pooling techniques: max pooling, average pooling, and stochastic pooling. The results showed that our method achieved a sensitivity of 96.88%, a specificity of 97.18%, and an accuracy of 97.04%. Our method was better than three state-of-the-art approaches. Besides, stochastic pooling performed better than other max pooling and average pooling. We validated CNN with five convolution layers and two fully connected layers performed the best. The GPU yielded a 149× acceleration in training and a 166× acceleration in test, compared to CPU.

Is energy pooling necessary in ultraviolet matrix-assisted laser desorption/ionization?

Science.gov (United States)

Lin, Hou-Yu; Song, Botao; Lu, I-Chung; Hsu, Kuo-Tung; Liao, Chih-Yu; Lee, Yin-Yu; Tseng, Chien-Ming; Lee, Yuan-Tseh; Ni, Chi-Kung

2014-01-15

Energy pooling has been suggested as the key process for generating the primary ions during ultraviolet matrix-assisted laser desorption/ionization (UV-MALDI). In previous studies, decreases in fluorescence quantum yields as laser fluence increased for 2-aminobenzoic acid, 2,5-dihydroxybenzoic acid (2,5-DHB), and 3-hydroxypicolinic acid were used as evidence of energy pooling. This work extends the research to other matrices and addresses whether energy pooling is a universal property in UV-MALDI. Energy pooling was investigated in a time-resolved fluorescence experiment by using a short laser pulse (355 nm, 20 ps pulse width) for excitation and a streak camera (1 ps time resolution) for fluorescence detection. The excited-state lifetime of 2,5-DHB decreased with increases in laser fluence. This suggests that a reaction occurs between two excited molecules, and that energy pooling may be one of the possible reactions. However, the excited-state lifetime of 2,4,6-trihydroxyacetophenone (THAP) did not change with increases in laser fluence. The upper limit of the energy pooling rate constant for THAP is estimated to be approximately 100-500 times smaller than that of 2,5-DHB. The small energy pooling rate constant for THAP indicates that the potential contribution of the energy pooling mechanism to the generation of THAP matrix primary ions should be reconsidered. Copyright © 2013 John Wiley & Sons, Ltd.

ENERGY STAR Certified Pool Pumps

Data.gov (United States)

U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 1.1 ENERGY STAR Program Requirements for Pool Pumps that are effective as of February 15,...

Conception of a sub aquatic lighting system for nuclear fuels storage pools

International Nuclear Information System (INIS)

Bracco, P.; Rosenthal, E.

1990-01-01

Restrictions like contaminated water, irradiated fuel elements in racks located on the bottom of the pool and the impossibility of removing the water, require a non conventional design of pool lamps. The model developed is independent of the pool, permitting easily fabrication and maintenance. They are made of stainless steel tubes with borosilicate windows, where floodlight or light are located. The lamp assembly is fixed at the border of the pool. The system offers advantages over the conventional pool lighting systems in fabrication, operation and maintenance. (author)

Strategies for chemically healthy public swimming pools

DEFF Research Database (Denmark)

Hansen, Kamilla Marie Speht

spreading of pathogens between swimmers because of its residual disinfection effect. In addition to potential contamination of pathogenic microorganisms, swimming pool water is polluted by organic matter deposited from the bathers such as saliva, urine, sweat, hair and personal care products. Since chlorine...... is a strong oxidant it oxidizes the organic matter in the pool water and forms disinfection byproducts (DBPs). More than 100 different DBPs have been identified. Some of these have been found to be genotoxic and may pose an increased cancer risk for the bathers. The aim of this thesis was to give an overview...... of the strategies which can be used to achieve microbiological safe water with low levels of DBPs to ensure healthy environment for bathers. There are different approaches to achieve healthy environment in public swimming pools which in this thesis are divided into three strategies: alternatives to chlorination...

Corium quench in deep pool mixing experiments

International Nuclear Information System (INIS)

Spencer, B.W.; McUmber, L.; Gregorash, D.; Aeschlimann, R.; Sienicki, J.J.

1985-01-01

The results of two recent corium-water thermal interaction (CWTI) tests are described in which a stream of molten corium was poured into a deep pool of water in order to determine the mixing behavior, the corium-to-water heat transfer rates, and the characteristic sizes of the quenched debris. The corium composition was 60% UO 2 , 16% ZrO 2 , and 24% stainless steel by weight; its initial temperature was 3080 K, approx.160 K above the oxide phase liquidus temperature. The corium pour stream was a single-phase 2.2 cm dia liquid column which entered the water pool in film boiling at approx.4 m/s. The water subcooling was 6 and 75C in the two tests. Test results showed that with low subcooling, rapid steam generation caused the pool to boil up into a high void fraction regime. In contrast, with large subcooling no net steam generation occurred, and the pool remained relatively quiescent. Breakup of the jet appeared to occur by surface stripping. In neither test was the breakup complete during transit through the 32 cm deep water pool, and molten corium channeled to the base where it formed a melt layer. The characteristic heat transfer rates measured 3.5 MJ/s and 2.7 MJ/s during the fall stage for small and large subcooling, respectively; during the initial stage of bed quench, the surface heat fluxes measured 2.4 MW/m 2 and 3.7 MW/m 2 , respectively. A small mass of particles was formed in each test, measuring typically 0.1 to 1 mm and 1 to 5 mm dia for the large and small subcooling conditions, respectively. 9 refs., 13 figs., 1 tab

Application of neutron noise analysis to a swimming pool research reactor

International Nuclear Information System (INIS)

Behringer, K.; Lescano, V.H.; Meier, F.; Phildius, J.; Winkler, H.

1982-01-01

This work is part of a programme of establishing practical applications of neutron noise techniques to a swimming pool research reactor and deals with two different items: (1) The identification of local boiling caused e.g. by a partial blockage of the coolant flow in a fuel element. Local boiling can easily lead to a burn-out situation. The onset of boiling can be detected by neutron noise analysis and a boiling detection system is presently under development. (2) The measurement of the time evolution of the reactivity induced by xenon after reactor shut-down by an on-line reactivity meter based on neutron noise analysis. From the data, the prompt neutron decay constant at delayed critical, the equilibrium xenon reactivity worth, and an estimate of the average steady-state power flux in the core before reactor shut-down were obtained. (author)

Single-bubble dynamics in pool boiling of one-component fluids

KAUST Repository

Xu, Xinpeng; Qian, Tiezheng

2014-01-01

We numerically investigate the pool boiling of one-component fluids with a focus on the effects of surface wettability on the single-bubble dynamics. We employed the dynamic van der Waals theory [Phys. Rev. E 75, 036304 (2007)], a diffuse-interface model for liquid-vapor flows involving liquid-vapor transition in nonuniform temperature fields. We first perform simulations for bubbles on homogeneous surfaces. We find that an increase in either the contact angle or the surface superheating can enhance the bubble spreading over the heating surface and increase the bubble departure diameter as well and therefore facilitate the transition into film boiling. We then examine the dynamics of bubbles on patterned surfaces, which incorporate the advantages of both hydrophobic and hydrophilic surfaces. The central hydrophobic region increases the thermodynamic probability of bubble nucleation while the surrounding hydrophilic region hinders the continuous bubble spreading by pinning the contact line at the hydrophobic-hydrophilic intersection. This leads to a small bubble departure diameter and therefore prevents the transition from nucleate boiling into film boiling. With the bubble nucleation probability increased and the bubble departure facilitated, the efficiency of heat transfer on such patterned surfaces is highly enhanced, as observed experimentally [Int. J. Heat Mass Transfer 57, 733 (2013)]. In addition, the stick-slip motion of contact line on patterned surfaces is demonstrated in one-component fluids, with the effect weakened by surface superheating.

Single-bubble dynamics in pool boiling of one-component fluids

KAUST Repository

Xu, Xinpeng

2014-06-04

We numerically investigate the pool boiling of one-component fluids with a focus on the effects of surface wettability on the single-bubble dynamics. We employed the dynamic van der Waals theory [Phys. Rev. E 75, 036304 (2007)], a diffuse-interface model for liquid-vapor flows involving liquid-vapor transition in nonuniform temperature fields. We first perform simulations for bubbles on homogeneous surfaces. We find that an increase in either the contact angle or the surface superheating can enhance the bubble spreading over the heating surface and increase the bubble departure diameter as well and therefore facilitate the transition into film boiling. We then examine the dynamics of bubbles on patterned surfaces, which incorporate the advantages of both hydrophobic and hydrophilic surfaces. The central hydrophobic region increases the thermodynamic probability of bubble nucleation while the surrounding hydrophilic region hinders the continuous bubble spreading by pinning the contact line at the hydrophobic-hydrophilic intersection. This leads to a small bubble departure diameter and therefore prevents the transition from nucleate boiling into film boiling. With the bubble nucleation probability increased and the bubble departure facilitated, the efficiency of heat transfer on such patterned surfaces is highly enhanced, as observed experimentally [Int. J. Heat Mass Transfer 57, 733 (2013)]. In addition, the stick-slip motion of contact line on patterned surfaces is demonstrated in one-component fluids, with the effect weakened by surface superheating.

Liquid sodium pool fires

Energy Technology Data Exchange (ETDEWEB)

Casselman, C [DSN/SESTR, Centre de Cadarache, Saint-Paul-lez-Durance (France)

1979-03-01

Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

Liquid sodium pool fires

International Nuclear Information System (INIS)

Casselman, C.

1979-01-01

Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

Hydrodynamics and heat transfer characteristics of liquid pools with bubble agitation

International Nuclear Information System (INIS)

Blottner, F.G.

1979-11-01

Estimates are given for the heat transfer coefficients at various interfaces which occur in molten pools on concrete. Previous simulant experiments and correlations are used to determine the hydrodynamic behavior of the pool and heat transfer coefficients for the liquids of interest. Other studies assume a gas film occurs between the concrete and molten pool, but the results of this investigation do not confirm this assumption. The results also indicate the significant influence the very viscous concrete slag has on the properties of the molten pool. Additional experiments and analysis are needed to improve the accuracy of the heat transfer coefficients estimated and to understand the behavior of the concrete slag at the interface between the pool and decomposing concrete

Investigation to radioactive contamination of pool water in IMEF

International Nuclear Information System (INIS)

Song, Ung Sup; Jung, Yang Hong; Lee, J. H.; Lee, H. K.

2003-06-01

The pool (3x6x10) in irradiated materials examination facility is usually used for the purpose of taking the specimen out of cask loaded into the pool, and carrying in/out the specimen to/ from the hot cell. Always, it must be cared for the water into the pool to be fine condition because all operation are worked with the naked eye during taking an irradiated materials out of the cask and plunging them in the bucket-elevator. In the aspects of the radioactive remained substances in the water must be controlled so that the amount of substances to be lower than the standard amount prescribed by RCA Korea Activity in a part of radioactive contamination control. In consequence, an expertness of status and a practical use of skill make possible the prevention of radioactive material's diffusion or the radioactive contamination of pool water and safety work

CAREM 25: Suppression pool cooling and purification system

International Nuclear Information System (INIS)

Carlevaris, Rodolfo; Patrignani, Alberto; Vindrola, Carlos; Palmerio, Hector D.; Quiroz, Horacio; Ramilo, Lucia B.

2000-01-01

The suppression pool cooling and purification system has the following main functions: purify and cool water from the suppression pool, cool and send water to the residual heat extraction system, and transfer water to the fuel element transference channel. In case of Loss of Coolant Accident (LOCA), the system sends water from the suppression pool to the spray network, thus cooling and reducing pressure in the primary containment. The system has been designed in accordance with the requirements of the following standards: ANSI/ANS 52.1; ANSI/ANS 57.2; ANSI/ANS 56.2; ANSI/ANS 59.1; ANSI/ANS 58.3; ANSI/ANS 58.9; and ANSI/ANS 56.5. The design of the system fulfils all the assigned functions. (author)

Topography Battles Surface Texture: An Experimental Study of Pool-riffle Formation

Science.gov (United States)

Chartrand, S. M.; Hassan, M. A.; Jellinek, M.

2016-12-01

Pool-riffles are perhaps the most common streambed shape found in streams and rivers, and not surprisingly, they are essential to salmon ecology, and are a central focus of many restoration actions. Yet, when an applied earth scientist or engineer is faced with developing a pool-riffle design, there is a lack of clear and rigorously developed design guidelines. Given the volumes of money spent annually within the restoration industry, this is a real problem. Recognition of this problem is growing, however, and an increasing level of attention has been directed to questions of pool-riffle formation in the past decade. At this point and given certain landscape characteristics, it is well established that streamwise gradients in channel width are associated with pool-riffles. Specifically, pools are associated with negative gradients in width, and riffles with positive gradients. Importantly, these associations have now been documented from field-derived data, as well as via experimental and numerical investigations. There is much to build from the present knowledge base, and central to this are questions related to (a) how pool-riffles evolve during the formative process, (b) what are the basic set of ingredients necessary for pool-riffle formation within systems characterized by relatively non-erodible channel margins, and (c) do pool-riffles persist, once formed, under a broad range of forcing conditions? We have completed four physical experiments examining the process and evolution of pool-riffle formation under a large range of upstream boundary, as well as physical channel conditions. We will report on two of the completed experiments. Our work will highlight two new non-dimensional channel evolution numbers, derived to help describe and characterize bedform development, as well as response to perturbations from near-equilibrium conditions. The channel evolution numbers lay the foundation for development of a new regime diagram, which quantifies the basic

Laboratory investigation and simulation of breakthrough curves in karst conduits with pools

Science.gov (United States)

Zhao, Xiaoer; Chang, Yong; Wu, Jichun; Peng, Fu

2017-12-01

A series of laboratory experiments are performed under various hydrological conditions to analyze the effect of pools in pipes on breakthrough curves (BTCs). The BTCs are generated after instantaneous injections of NaCl tracer solution. In order to test the feasibility of reproducing the BTCs and obtain transport parameters, three modeling approaches have been applied: the equilibrium model, the linear graphical method and the two-region nonequilibrium model. The investigation results show that pools induce tailing of the BTCs, and the shapes of BTCs depend on pool geometries and hydrological conditions. The simulations reveal that the two-region nonequilibrium model yields the best fits to experimental BTCs because the model can describe the transient storage in pools by the partition coefficient and the mass transfer coefficient. The model parameters indicate that pools produce high dispersion. The increased tailing occurs mainly because the partition coefficient decreases, as the number of pools increases. When comparing the tracer BTCs obtained using the two types of pools with the same size, the more appreciable BTC tails that occur for symmetrical pools likely result mainly from the less intense exchange between the water in the pools and the water in the pipe, because the partition coefficients for the two types of pools are virtually identical. Dispersivity values decrease as flow rates increase; however, the trend in dispersion is not clear. The reduced tailing is attributed to a decrease in immobile water with increasing flow rate. It provides evidence for hydrodynamically controlled tailing effects.

17 CFR 275.206(4)-8 - Pooled investment vehicles.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Pooled investment vehicles... COMMISSION (CONTINUED) RULES AND REGULATIONS, INVESTMENT ADVISERS ACT OF 1940 § 275.206(4)-8 Pooled investment vehicles. (a) Prohibition. It shall constitute a fraudulent, deceptive, or manipulative act...

Anticipated corrosion in the Vermont Yankee spent fuel pool

International Nuclear Information System (INIS)

Weeks, J.R.

1977-06-01

The report provides additional information relating to a proposed modification to the spent fuel pool at the Vermont Yankee Nuclear Power Station (VYNPS) and addresses corrosion of spent fuel pool storage materials and zircaloy, and provides an analysis of the effectiveness of the Boral sealing

A Mechanistic Model of Waterfall Plunge Pool Erosion into Bedrock

Science.gov (United States)

Scheingross, Joel S.; Lamb, Michael P.

2017-11-01

Landscapes often respond to changes in climate and tectonics through the formation and upstream propagation of knickzones composed of waterfalls. Little work has been done on the mechanics of waterfall erosion, and instead most landscape-scale models neglect waterfalls or use rules for river erosion, such as stream power, that may not be applicable to waterfalls. Here we develop a physically based model to predict waterfall plunge pool erosion into rock by abrasion from particle impacts and test the model against flume experiments. Both the model and experiments show that evolving plunge pools have initially high vertical erosion rates due to energetic particle impacts, and erosion slows and eventually ceases as pools deepen and deposition protects the pool floor from further erosion. Lateral erosion can continue after deposition on the pool floor, but it occurs at slow rates that become negligible as pools widen. Our work points to the importance of vertical drilling of successive plunge pools to drive upstream knickzone propagation in homogenous rock, rather than the classic mechanism of headwall undercutting. For a series of vertically drilling waterfalls, we find that upstream knickzone propagation is faster under higher combined water and sediment fluxes and for knickzones composed of many waterfalls that are closely spaced. Our model differs significantly from stream-power-based erosion rules in that steeper knickzones can retreat faster or more slowly depending on the number and spacing of waterfalls within a knickzone, which has implications for interpreting climatic and tectonic history through analysis of river longitudinal profiles.

Mitochondrial deoxyribonucleoside triphosphate pools in thymidine kinase 2 deficiency.

Science.gov (United States)

Saada, Ann; Ben-Shalom, Efrat; Zyslin, Rivka; Miller, Chaya; Mandel, Hanna; Elpeleg, Orly

2003-10-24

Deficiency of mitochondrial thymidine kinase (TK2) is associated with mitochondrial DNA (mtDNA) depletion and manifests by severe skeletal myopathy in infancy. In order to elucidate the pathophysiology of this condition, mitochondrial deoxyribonucleoside triphosphate (dNTP) pools were determined in patients' fibroblasts. Despite normal mtDNA content and cytochrome c oxidase (COX) activity, mitochondrial dNTP pools were imbalanced. Specifically, deoxythymidine triphosphate (dTTP) content was markedly decreased, resulting in reduced dTTP:deoxycytidine triphosphate ratio. These findings underline the importance of balanced mitochondrial dNTP pools for mtDNA synthesis and may serve as the basis for future therapeutic interventions.

Core-concrete molten pool dynamics and interfacial heat transfer

International Nuclear Information System (INIS)

Benjamin, A.S.

1980-01-01

Theoretical models are derived for the heat transfer from molten oxide pools to an underlying concrete surface and from molten steel pools to a general concrete containment. To accomplish this, two separate effects models are first developed, one emphasizing the vigorous agitation of the molten pool by gases evolving from the concrete and the other considering the insulating effect of a slag layer produced by concrete melting. The resulting algebraic expressions, combined into a general core-concrete heat transfer representation, are shown to provide very good agreement with experiments involving molten steel pours into concrete crucibles

Gene Pools and the Genetic Architecture of Domesticated Cowpea

Directory of Open Access Journals (Sweden)

Bao-Lam Huynh

2013-11-01

Full Text Available Cowpea [ (L. Walp.] is a major tropical legume crop grown in warm to hot areas throughout the world and especially important to the people of sub-Saharan Africa where the crop was domesticated. To date, relatively little is understood about its domestication origins and patterns of genetic variation. In this study, a worldwide collection of cowpea landraces and African ancestral wild cowpea was genotyped with more than 1200 single nucleotide polymorphism markers. Bayesian inference revealed the presence of two major gene pools in cultivated cowpea in Africa. Landraces from gene pool 1 are mostly distributed in western Africa while the majority of gene pool 2 are located in eastern Africa. Each gene pool is most closely related to wild cowpea in the same geographic region, indicating divergent domestication processes leading to the formation of two gene pools. The total genetic variation within landraces from countries outside Africa was slightly greater than within African landraces. Accessions from Asia and Europe were more related to those from western Africa while accessions from the Americas appeared more closely related to those from eastern Africa. This delineation of cowpea germplasm into groups of genetic relatedness will be valuable for guiding introgression efforts in breeding programs and for improving the efficiency of germplasm management.

LCG Persistency Framework (POOL, CORAL, COOL) - Status and Outlook

CERN Multimedia

CERN. Geneva

2012-01-01

The LCG Persistency Framework consists of three software packages (POOL, CORAL and COOL) that address the data access requirements of the LHC experiments in several different areas. The project is the result of the collaboration between the CERN IT Department and the three experiments (ATLAS, CMS and LHCb) that are using some or all of the Persistency Framework components to access their data. The POOL package is a hybrid technology store for C++ objects, using a mixture of streaming and relational technologies to implement both object persistency and object metadata catalogs and collections. POOL provides generic components that can be used by the experiments to store both their event data and their conditions data. The CORAL package is an abstraction layer with an SQL-free API for accessing data stored using relational database technologies. It is used directly by experiment-specific applications and internally by both COOL and POOL. The COOL package provides specific software components and tools for the h...

Study on Dynamic Development of Three-dimensional Weld Pool Surface in Stationary GTAW

Science.gov (United States)

Huang, Jiankang; He, Jing; He, Xiaoying; Shi, Yu; Fan, Ding

2018-04-01

The weld pool contains abundant information about the welding process. In particular, the type of the weld pool surface shape, i. e., convex or concave, is determined by the weld penetration. To detect it, an innovative laser-vision-based sensing method is employed to observe the weld pool surface of the gas tungsten arc welding (GTAW). A low-power laser dots pattern is projected onto the entire weld pool surface. Its reflection is intercepted by a screen and captured by a camera. Then the dynamic development process of the weld pool surface can be detected. By observing and analyzing, the change of the reflected laser dots reflection pattern, for shape of the weld pool surface shape, was found to closely correlate to the penetration of weld pool in the welding process. A mathematical model was proposed to correlate the incident ray, reflected ray, screen and surface of weld pool based on structured laser specular reflection. The dynamic variation of the weld pool surface and its corresponding dots laser pattern were simulated and analyzed. By combining the experimental data and the mathematical analysis, the results show that the pattern of the reflected laser dots pattern is closely correlated to the development of weld pool, such as the weld penetration. The concavity of the pool surface was found to increase rapidly after the surface shape was changed from convex to concave during the stationary GTAW process.

The burning and smoke release rates of sodium pool fires

International Nuclear Information System (INIS)

Newman, R.N.; Payne, J.F.B.

1976-10-01

The burning rates and smoke release fractions of sodium pool fires have been measured over the pool temperature range 250 0 C to 750 0 C. A theoretical model is derived which satisfactorily predicts the burning rate over the above temperature range. The theory further predicts that the burning rate should be independent of pool diameter, a prediction supported by a comparison of burning rate data from this study and available data from other studies. (author)

Biophysical Interactions within Step-Pool Mountain Streams Following Wildfire

Science.gov (United States)

Parker, A.; Chin, A.; O'Dowd, A. P.

2014-12-01

Recovery of riverine ecosystems following disturbance is driven by a variety of interacting processes. Wildfires pose increasing disturbances to riverine landscapes, with rising frequencies and magnitudes owing to warming climates and increased fuel loads. The effects of wildfire include loss of vegetation, elevated runoff and flash floods, erosion and deposition, and changing biological habitats and communities. Understanding process interactions in post-fire landscapes is increasingly urgent for successful management and restoration of affected ecosystems. In steep channels, steps and pools provide prominent habitats for organisms and structural integrity in high energy environments. Step-pools are typically stable, responding to extreme events with recurrence intervals often exceeding 50 years. Once wildfire occurs, however, intensification of post-fire flood events can potentially overpower the inherent stability of these systems, with significant consequences for aquatic life and human well-being downstream. This study examined the short-term response of step-pool streams following the 2012 Waldo Canyon Fire in Colorado. We explored interacting feedbacks among geomorphology, hydrology, and ecology in the post-fire environment. At selected sites with varying burn severity, we established baseline conditions immediately after the fire with channel surveys, biological assessment using benthic macroinvertebrates, sediment analysis including pebble counts, and precipitation gauging. Repeat measurements after major storm events over several years enabled analysis of the interacting feedbacks among post-fire processes. We found that channels able to retain the step-pool structure changed less and facilitated recovery more readily. Step habitats maintained higher percentages of sensitive macroinvertebrate taxa compared to pools through post-fire floods. Sites burned with high severity experienced greater reduction in the percentage of sensitive taxa. The decimation of

Research progresses and future directions on pool boiling heat transfer

Directory of Open Access Journals (Sweden)

M. Kumar

2015-12-01

Full Text Available This paper reviews the previous work carried on pool boiling heat transfer during heating of various liquids and commodities categorized as refrigerants and dielectric fluids, pure liquids, nanofluids, hydrocarbons and additive mixtures, as well as natural and synthetic colloidal solutions. Nucleate pool boiling is an efficient and effective method of boiling because high heat fluxes are possible with moderate temperature differences. It is characterized by the growth of bubbles on a heated surface. It occurs during boiling of liquids for excess temperature ranging from 5 to 30 °C in various processes related to high vaporization of liquid for specific purposes like sugarcane juice heating for jaggery making, milk heating for khoa making, steam generation, cooling of electronic equipments, refrigeration and etcetera. In this review paper, pool boiling method during heating of liquids for specific purpose is depicted. It is inferred that enhancement in pool boiling heat transfer is a challenging and complex task. Also, recent research and use of various correlations for natural convection pool boiling is reviewed.

Safety analysis of a pool Genesis II irradiator

International Nuclear Information System (INIS)

Rodrigues Junior, Ary de A.

2011-01-01

The Genesis II Irradiator manufactured by GRAT * STAR Inc. (USA) is a category III gamma irradiator in which the sealed source is contained in a water filled storage pool and is shielded permanently, i.e. the material has to move down to the source. Even though the pool is 5.6 m deep, what would happen if the water level lowered? There are a series of safety devices that will avoid this situation and calculations show that the water level has to be very low in order to deliver a significant dose; moreover, only in case a person remains at the border of the pool for a long time this would be risky. In conclusion, it is practically impossible for someone to be exposed to radiation from a Genesis II Irradiator source. (author)

CAREM-25. Suppression Pool Cooling and Purification System

International Nuclear Information System (INIS)

Carlevaris, Rodolfo; Palmerio, D.; Patrignani, A.; Quiroz, H.; Ramilo, L.; Vindrola, C.

2000-01-01

The Suppression Pool Cooling and Purification System has the following main functions: purify and cool water from the Suppression Pool, cool and send water to the Residual Heat Extraction System, and transfer water to the Fuel Element Transference Channel. In case of Loss of Coolant Accident (LOCA), the system sends water from the Suppression Pool to the spray network, thus cooling and reducing pressure in the primary containment.The system has been designed in accordance with the requirements of the following standards ANSI/ANS 52.1 [1], ANSI/ANS 57.2 [2], ANSI/ANS 56.2 [3], ANSI/ANS 59.1 [4] ANSI/ANS 58.3 [5], ANSI/ANS 58.9 [6], and ANSI/ANS 56.5 [7]. The design of the system fulfils all the assigned functions

Pooled biological specimens for human biomonitoring of environmental chemicals: opportunities and limitations.

Science.gov (United States)

Heffernan, Amy L; Aylward, Lesa L; Toms, Leisa-Maree L; Sly, Peter D; Macleod, Matthew; Mueller, Jochen F

2014-01-01

Biomonitoring has become the "gold standard" in assessing chemical exposures, and has an important role in risk assessment. The pooling of biological specimens-combining multiple individual specimens into a single sample-can be used in biomonitoring studies to monitor levels of exposure and identify exposure trends or to identify susceptible populations in a cost-effective manner. Pooled samples provide an estimate of central tendency and may also reveal information about variation within the population. The development of a pooling strategy requires careful consideration of the type and number of samples collected, the number of pools required and the number of specimens to combine per pool in order to maximise the type and robustness of the data. Creative pooling strategies can be used to explore exposure-outcome associations, and extrapolation from other larger studies can be useful in identifying elevated exposures in specific individuals. The use of pooled specimens is advantageous as it saves significantly on analytical costs, may reduce the time and resources required for recruitment and, in certain circumstances, allows quantification of samples approaching the limit of detection. In addition, the use of pooled samples can provide population estimates while avoiding ethical difficulties that may be associated with reporting individual results.

Phytomass carbon pool of trees and forests in India

NARCIS (Netherlands)

Kaul, M.; Mohren, G.M.J.; Dadhwal, V.K.

2011-01-01

The study reports estimates of above ground phytomass carbon pools in Indian forests for 1992 and 2002 using two different methodologies. The first estimate was derived from remote sensing based forest area and crown density estimates, and growing stock data for 1992 and 2002 and the estimated pool

Experimental characterization of the weld pool flow in a TIG configuration

Science.gov (United States)

Stadler, M.; Masquère, M.; Freton, P.; Franceries, X.; Gonzalez, J. J.

2014-11-01

Tungsten Inert Gas (TIG) welding process relies on heat transfer between plasma and work piece leading to a metallic weld pool. Combination of different forces produces movements on the molten pool surface. One of our aims is to determine the velocity on the weld pool surface. This provides a set of data that leads to a deeper comprehension of the flow behavior and allows us to validate numerical models used to study TIG parameters. In this paper, two diagnostic methods developed with high speed imaging for the determination of velocity of an AISI 304L stainless steel molten pool are presented. Application of the two methods to a metallic weld pool under helium with a current intensity of 100 A provides velocity values around 0.70 m/s which are in good agreement with literature works.

Zooplankton at deep Red Sea brine pools

KAUST Repository

Kaartvedt, Stein

2016-03-02

The deep-sea anoxic brines of the Red Sea comprise unique, complex and extreme habitats. These environments are too harsh for metazoans, while the brine–seawater interface harbors dense microbial populations. We investigated the adjacent pelagic fauna at two brine pools using net tows, video records from a remotely operated vehicle and submerged echosounders. Waters just above the brine pool of Atlantis II Deep (2000 m depth) appeared depleted of macrofauna. In contrast, the fauna appeared to be enriched at the Kebrit Deep brine–seawater interface (1466 m).

Mathematical modelling and simulation of the thermal performance of a solar heated indoor swimming pool

Directory of Open Access Journals (Sweden)

Mančić Marko V.

2014-01-01

Full Text Available Buildings with indoor swimming pools have a large energy footprint. The source of major energy loss is the swimming pool hall where air humidity is increased by evaporation from the pool water surface. This increases energy consumption for heating and ventilation of the pool hall, fresh water supply loss and heat demand for pool water heating. In this paper, a mathematical model of the swimming pool was made to assess energy demands of an indoor swimming pool building. The mathematical model of the swimming pool is used with the created multi-zone building model in TRNSYS software to determine pool hall energy demand and pool losses. Energy loss for pool water and pool hall heating and ventilation are analyzed for different target pool water and air temperatures. The simulation showed that pool water heating accounts for around 22%, whereas heating and ventilation of the pool hall for around 60% of the total pool hall heat demand. With a change of preset controller air and water temperatures in simulations, evaporation loss was in the range 46-54% of the total pool losses. A solar thermal sanitary hot water system was modelled and simulated to analyze it's potential for energy savings of the presented demand side model. The simulation showed that up to 87% of water heating demands could be met by the solar thermal system, while avoiding stagnation. [Projekat Ministarstva nauke Republike Srbije, br. III 42006: Research and development of energy and environmentally highly effective polygeneration systems based on using renewable energy sources

High efficiency pool filtering systems utilising variable frequency drives

Energy Technology Data Exchange (ETDEWEB)

Hameiri, Z.; Sproul, A.B. [School of Photovoltaic and Renewable Energy Engineering, UNSW, Sydney, NSW 2052 (Australia); Spooner, T. [School of Electrical Engineering and Telecommunications, UNSW, Sydney, NSW 2052 (Australia)

2009-02-15

Over 1 year, private swimming pools in Australia will typically consume 1680 GWh of electricity, producing 2130 kt of CO{sub 2}. Redesigning a pool's filtration system and using it more efficiently can reduce the energy use, and hence the CO{sub 2} production, by a significant amount. This paper describes experimental measurements carried out on a new design of pool pump system. Initial experiments using a variable frequency drive (VFD) with a standard, single phase pump/motor system have achieved energy savings of 40%. Utilising a VFD and a three phase pump/motor energy savings of 61% have been achieved, without degrading the system performance. (author)

Second-line salvage treatment of AIDS-associated Pneumocystis jirovecii pneumonia: a case series and systematic review

DEFF Research Database (Denmark)

Benfield, T.; Atzori, C.; Miller, R.F.

2008-01-01

BACKGROUND: Limited clinical data exist to guide the choice of second-line salvage treatment for AIDS-associated Pneumocystis jirovecii pneumonia (PCP). METHODS: We did a systematic search of MEDLINE for all randomized and observational studies of PCP treatment published up to August 2007...... and included individual treatment data of AIDS-associated PCP from a tricenter study. We calculated pooled estimates of reported outcome of second-line treatment using averaged odds ratios (ORs). RESULTS: Twenty-nine studies with sufficient detail of second-line treatment and outcome, including data from 82...... individual cases from the tricenter study, yielded a total of 468 PCP second-line treatment episodes. Response rates to second-line treatment were comparable for trimethoprim-sulfamethoxazole (TMP-SMX; 68%) and clindamycin-primaquine (73%) (OR for response = 2.1 [95% confidence interval (CI): 1.1 to 3...

Cryptosporidium and Giardia in Swimming Pools, Atlanta, Georgia

Centers for Disease Control (CDC) Podcasts

In this podcast, Dan Rutz speaks with Dr. Joan Shields, a guest researcher with the Healthy Swimming Program at CDC, about an article in June 2008 issue of Emerging Infectious Diseases reporting on the results of a test of swimming pools in the greater Atlanta, Georgia area. Dr. Shields tested 160 pools in metro Atlanta last year for Cryptosporidium and Giardia. These germs cause most recreational water associated outbreaks.

Upper arm circumference development in Chinese children and adolescents: a pooled analysis.

Science.gov (United States)

Tong, Fang; Fu, Tong

2015-05-30

Upper arm development in children is different in different ethnic groups. There have been few reports on upper arm circumference (UAC) at different stages of development in children and adolescents in China. The purpose of this study was to provide a reference for growth with weighted assessment of the overall level of development. Using a pooled analysis, an authoritative journal database search and reports of UAC, we created a new database on developmental measures in children. In conducting a weighted analysis, we compared reference values for 0~60 months of development according to the World Health Organization (WHO) statistics considering gender and nationality and used Z values as interval values for the second sampling to obtain an exponential smooth curve to analyze the mean, standard deviation, and sites of attachment. Ten articles were included in the pooled analysis, and these articles included participants from different areas of China. The point of intersection with the WHO curve was 3.5 years with higher values at earlier ages and lower values at older ages. Boys curve was steeper after puberty. The curves in the studies had a merged line compatible. The Z values of exponential smoothing showed the curves were similar for body weight and had a right normal distribution. The integrated index of UAC in Chinese children and adolescents indicated slightly variations with regions. Exponential curve smoothing was suitable for assessment at different developmental stages.

New set of convective heat transfer coefficients established for pools and validated against CLARA experiments for application to corium pools

Energy Technology Data Exchange (ETDEWEB)

Michel, B., E-mail: benedicte.michel@irsn.fr

2015-05-15

Highlights: • A new set of 2D convective heat transfer correlations is proposed. • It takes into account different horizontal and lateral superficial velocities. • It is based on previously established correlations. • It is validated against recent CLARA experiments. • It has to be implemented in a 0D MCCI (molten core concrete interaction) code. - Abstract: During an hypothetical Pressurized Water Reactor (PWR) or Boiling Water Reactor (BWR) severe accident with core meltdown and vessel failure, corium would fall directly on the concrete reactor pit basemat if no water is present. The high temperature of the corium pool maintained by the residual power would lead to the erosion of the concrete walls and basemat of this reactor pit. The thermal decomposition of concrete will lead to the release of a significant amount of gases that will modify the corium pool thermal hydraulics. In particular, it will affect heat transfers between the corium pool and the concrete which determine the reactor pit ablation kinetics. A new set of convective heat transfer coefficients in a pool with different lateral and horizontal superficial gas velocities is modeled and validated against the recent CLARA experimental program. 155 tests of this program, in two size configurations and a high range of investigated viscosity, have been used to validate the model. Then, a method to define different lateral and horizontal superficial gas velocities in a 0D code is proposed together with a discussion about the possible viscosity in the reactor case when the pool is semi-solid. This model is going to be implemented in the 0D ASTEC/MEDICIS code in order to determine the impact of the convective heat transfer in the concrete ablation by corium.

Raw data from the Italian National Forest Inventory are on-line and publicly available

Directory of Open Access Journals (Sweden)

Borghetti M

2016-12-01

Full Text Available Raw data from the Italian National Forest Inventory are on-line and publicly available. The National Forest Service in cooperation with the Forest Monitoring and Management Research Unit of the Council for Agricultural Research and Economics (CREA released the raw data from the National Inventory of Forests and forest Carbon pools - INFC2005 project, the second Italian national forest inventory. Data are available together with metadata information at http://www.inventarioforestale.org/. Users, after registration, can download data from 230.874 living tree stems, 16.472 dead tree stems, 31.083 stumps, from a total of 7.272 field plots (for 1.384 of them additional data on fine woody debris and soil carbon pools are also available.

Comparison of fecal pooling strategies for detection of Mycobacterium avium ssp. paratuberculosis in cattle.

Science.gov (United States)

McKenna, S L B; Ritter, C; Dohoo, I; Keefe, G P; Barkema, H W

2018-05-23

In herds with typical moderate to low within-herd prevalence, testing for Mycobacterium avium ssp. paratuberculosis (MAP), the infectious agent of Johne's disease, will be more cost-effective if individual fecal samples are cultured in composite pools. However, sensitivity to classify a pool containing 1 or more positive individual samples as positive may depend on pool size and number of individual positive samples within a pool. Fecal samples collected from 994 dairy cows sampled at slaughter were cultured to detect MAP. Culturing was done both individually and as composite pooled samples using the TREK ESP Culture System II broth medium (Thermo Fisher Scientific, Trek Diagnostic Systems Inc., Cleveland, OH). Composite samples consisted of pools containing feces from 3, 5, 8, 10, or 15 cows. The number of individual fecal culture-positive cows within each pool ranged from 0 to 4. Culture of individual fecal samples detected MAP in 36 (3.6%) of the 994 cows. Individual samples that were detected within the first 50 d by TREK ESP Culture System II were more likely to lead to a positive pool result. In total, 840 pooled fecal samples were examined for presence of MAP, and of those, 272 pools actually contained feces from fecal culture-positive cows. The crude sensitivity (proportion of pools that contained at least 1 fecal-positive cow that tested positive) for pools of 3, 5, 8, 10, and 15 was 47, 67, 44, 59, and 39%, respectively. Across pools, an increase of the number of fecal culture-positive samples from 1 to 2 enhanced overall crude sensitivity from 44 to 71%. However, sensitivity did not further increase for pools with 3 or 4 fecal culture-positive samples (63 and 60%, respectively). Additionally, a simulation analysis assessing probability of pooled fecal samples being positive in herds of 50 and 100 cows was conducted. The simulation assumed that 1, 2, or 5 cows per herd were MAP fecal culture-positive and that pools of 5 and 10 were used. This low

Strong influence of regional species pools on continent-wide structuring of local communities

DEFF Research Database (Denmark)

Lessard, Jean-Philippe; Borregaard, Michael Krabbe; Fordyce, James A.

2012-01-01

pool, to examine the interplay between broad-scale evolutionary and fine-scale ecological processes. Finally, a renewed interest in the influence of species source pools on communities has shown that the definition of the source pool influences interpretations of patterns of community structure. We use...... of communities along climatic gradients. We find that the average phylogenetic relatedness of species in ant communities decreases from tropical to temperate regions, but the strength of this relationship depends on the level of ecological realism in the definition of source pools. We conclude that the evolution...... of climatic niches influences the phylogenetic structure of regional source pools and that the influence of regional source pools on local community structure is strong....

Heat and fission product transport in molten core material pool with crust

International Nuclear Information System (INIS)

Yun, J.I.; Suh, K.Y.; Kang, C.S.

2005-01-01

Heat transfer and fluid flow in a molten pool are influenced by internal volumetric heat generated from the radioactive decay of fission product species retained in the reactor vessel during a severe accident. The pool superheat is determined based on the overall energy balance that equates the heat production rate to the heat loss rate. Decay heat of fission products in the pool is estimated by product of the mass concentration and energy conversion factor of each fission product. Twenty-nine elements are chosen and classified by their chemical properties to calculate heat generation rate in the pool. The mass concentration of a fission product is obtained from released fraction and the tabular output of the ORIGEN 2 code. The initial core and pool inventories at each time can also be estimated using ORIGEN 2. The released fraction of each fission product is calculated based on the bubble dynamics and mass transport. Numerical analysis is performed for heat and fission product transport in a molten core material pool during the Three Mile Island Unit 2 (TMI-2) accident. The pool is assumed to be a partially filled hemisphere, whose change in geometry is neglected during the numerical calculation. Calculated results indicate that the peak temperature in the molten pool is significantly lowered, since a substantial amount of the volatile fission products is released from the molten pool during progression of the accident. The results may directly be applied to the existing severe accident analysis codes to more mechanistically determine the thermal load to the reactor vessel lower head during the in-vessel retention

A protocol for measuring spatial variables in soft-sediment tide pools

Directory of Open Access Journals (Sweden)

Marina R. Brenha-Nunes

2016-01-01

Full Text Available ABSTRACT We present a protocol for measuring spatial variables in large (>50 m2 soft-sediment tide pool. Secondarily, we present the fish capture efficiency of a sampling protocol that based on such spatial variables to calculate relative abundances. The area of the pool is estimated by summing areas of basic geometric forms; the depth, by taken representative measurements of the depth variability of each pool's sector, previously determined according to its perimeter; and the volume, by considering the pool as a prism. These procedures were a trade-off between the acquisition of reliable estimates and the minimization of both the cost of operating and the time spent in field. The fish sampling protocol is based on two con secutive stages: 1 two people search for fishes under structures (e.g., rocks and litters on the pool and capture them with hand seines; 2 these structures are removed and then a beach-seine is hauled over the whole pool. Our method is cheaper than others and fast to operate considering the time in low tides. The method to sample fish is quite efficient resulting in a capture efficiency of 89%.

Afterlife of a Drop Impacting a Liquid Pool

Science.gov (United States)

Saha, Abhishek; Wei, Yanju; Tang, Xiaoyu; Law, Chung K.

2017-11-01

Drop impact on liquid pool is ubiquitous in industrial processes, such as inkjet printing and spray coating. While merging of drop with the impacted liquid surface is essential to facilitate the printing and coating processes, it is the afterlife of this merged drop and associated mixing which control the quality of the printed or coated surface. In this talk we will report an experimental study on the structural evolution of the merged droplet inside the liquid pool. First, we will analyze the depth of the crater created on the pool surface by the impacted drop for a range of impact inertia, and we will derive a scaling relation and the associated characteristic time-scale. Next, we will focus on the toroidal vortex formed by the moving drop inside the liquid pool and assess the characteristic time and length scales of the penetration process. The geometry of the vortex structure which qualitatively indicates the degree of mixedness will also be discussed. Finally, we will present the results from experiments with various viscosities to demonstrate the role of viscous dissipation on the geometry and structure formed by the drop. This work is supported by the Army Research Office and the Xerox Corporation.

Crowd density estimation based on convolutional neural networks with mixed pooling

Science.gov (United States)

Zhang, Li; Zheng, Hong; Zhang, Ying; Zhang, Dongming

2017-09-01

Crowd density estimation is an important topic in the fields of machine learning and video surveillance. Existing methods do not provide satisfactory classification accuracy; moreover, they have difficulty in adapting to complex scenes. Therefore, we propose a method based on convolutional neural networks (CNNs). The proposed method improves performance of crowd density estimation in two key ways. First, we propose a feature pooling method named mixed pooling to regularize the CNNs. It replaces deterministic pooling operations with a parameter that, by studying the algorithm, could combine the conventional max pooling with average pooling methods. Second, we present a classification strategy, in which an image is divided into two cells and respectively categorized. The proposed approach was evaluated on three datasets: two ground truth image sequences and the University of California, San Diego, anomaly detection dataset. The results demonstrate that the proposed approach performs more effectively and easily than other methods.

Strong influence of regional species pools on continent-wide structuring of local communities.

Science.gov (United States)

Lessard, Jean-Philippe; Borregaard, Michael K; Fordyce, James A; Rahbek, Carsten; Weiser, Michael D; Dunn, Robert R; Sanders, Nathan J

2012-01-22

There is a long tradition in ecology of evaluating the relative contribution of the regional species pool and local interactions on the structure of local communities. Similarly, a growing number of studies assess the phylogenetic structure of communities, relative to that in the regional species pool, to examine the interplay between broad-scale evolutionary and fine-scale ecological processes. Finally, a renewed interest in the influence of species source pools on communities has shown that the definition of the source pool influences interpretations of patterns of community structure. We use a continent-wide dataset of local ant communities and implement ecologically explicit source pool definitions to examine the relative importance of regional species pools and local interactions for shaping community structure. Then we assess which factors underlie systematic variation in the structure of communities along climatic gradients. We find that the average phylogenetic relatedness of species in ant communities decreases from tropical to temperate regions, but the strength of this relationship depends on the level of ecological realism in the definition of source pools. We conclude that the evolution of climatic niches influences the phylogenetic structure of regional source pools and that the influence of regional source pools on local community structure is strong.

Gene pool conservation of teak in Myanmar

International Nuclear Information System (INIS)

Tin-Tun

1995-01-01

Myanmar with an area of 261, 228 Sq. miles is endowed with various types of forests which occupied nearly 50% of the country. Teak (Tectona grandis Linn. f.) is one of the most valuable timber species for its excellent wood quality and properties which are not observed with other timbers. Gene pool can be defined as a group of individual trees growing over a wide range of environmental conditions, and constituting different genetic complexes which can be transmitted to the offsprings. Topics such as: objectives of gene pool conservation, genetically improved seeds for large scale forest plantations, methodology of conservation, are discussed in the article. Myanmar teak dominates the world's teak market, and thus it is crucial to maintain the superiority in the conservation of gene complexes of teak. To some extent, the conservation of gene pools of teak and tree improvements are being undertaken by the Forest Research Institute of Myanmar. It is felt that the dissemination of the philosophy and concept of gene conservation to the personal involved in the forestry activities of the country are still inadequate

Frozen gene pools - A future for species otherwise destined for extinction

Science.gov (United States)

Gee, G.F.

1986-01-01

Conclusion: Semen banks and ova and embryo banks can be practical methods to maintain gene pools. Gene pool preservation is desperately needed today due to the rapid decline in number of species and their habitat, a matter that is of concern to.biologists, economists, and politicians worldwide. Techniques are available for the cryopreservation of semen from many animals (and embryos from a few mammals) and adaptations of these techniques to other animals should be possible. A frozen gene pool in conjunction with existing programs makes it possible to preserve gene pools at less cost or in.some cases where no other alternative to extinction existed.

Sculpting the Barnyard Gene Pool

Science.gov (United States)

Childers, Gina; Wolfe, Kim; Dupree, Alan; Young, Sheila; Caver, Jessica; Quintanilla, Ruby; Thornton, Laura

2016-01-01

Project-based learning (PBL) takes student engagement to a higher level through reflective collaboration, inquiry, critical thinking, problem solving, and personal relevance. This article explains how six high school teachers developed an interconnected, interdisciplinary STEM-focused PBL called "Sculpting the Barnyard Gene Pool." The…

Survey of bacterial contamination of environment of swimming pools in Yazd city, in 2013

Directory of Open Access Journals (Sweden)

Hossein Jafari Mansoorian

2015-09-01

Full Text Available Background: Infections are readily transmitted as a result of bacterial contamination of swimming pools. Therefore, hygiene and preventing the contamination of swimming pools is of particular importance. The objective of this study was to determine the amount of bacterial contamination in indoor pools of Yazd in 2013. Methods: In this descriptive and analytical study, all indoor swimming pools of Yazd (12 pools were evaluated during the spring and summer of 2013, in terms of bacterial contamination. In order to determine contamination, a sterile cotton swab was used for sampling. On average, 45 samples were taken from different surfaces in each pool (shower, dressing room, sitting places in sauna, platforms and around the pool. In total, about 540 samples from all pools were tested for bacterial contamination. Results: The results show that from 540 samples, bacterial contamination was observed in about 93 samples (17.22%; and was seen more in showers, edges of the pool and jacuzzis, and the slippers used in swimming pools. The most important isolated bacteria types were E. coli, Actinobacteria, Pseudomonas alcaligenes, Pseudomonas aeruginosa and Klebsiella pneumonia. Conclusion: The results indicate the presence of bacterial contamination on the surface of these places. It is recommended that health authorities should pay more attention to cleaning and disinfecting surfaces around the pool, showers, dressing rooms etc, to prevent infectious disease transfer as a result of contact with contaminated swimming pool surfaces.

UPDG: Utilities package for data analysis of Pooled DNA GWAS

Directory of Open Access Journals (Sweden)

Ho Daniel WH

2012-01-01

Full Text Available Abstract Background Despite being a well-established strategy for cost reduction in disease gene mapping, pooled DNA association study is much less popular than the individual DNA approach. This situation is especially true for pooled DNA genomewide association study (GWAS, for which very few computer resources have been developed for its data analysis. This motivates the development of UPDG (Utilities package for data analysis of Pooled DNA GWAS. Results UPDG represents a generalized framework for data analysis of pooled DNA GWAS with the integration of Unix/Linux shell operations, Perl programs and R scripts. With the input of raw intensity data from GWAS, UPDG performs the following tasks in a stepwise manner: raw data manipulation, correction for allelic preferential amplification, normalization, nested analysis of variance for genetic association testing, and summarization of analysis results. Detailed instructions, procedures and commands are provided in the comprehensive user manual describing the whole process from preliminary preparation of software installation to final outcome acquisition. An example dataset (input files and sample output files is also included in the package so that users can easily familiarize themselves with the data file formats, working procedures and expected output. Therefore, UPDG is especially useful for users with some computer knowledge, but without a sophisticated programming background. Conclusions UPDG provides a free, simple and platform-independent one-stop service to scientists working on pooled DNA GWAS data analysis, but with less advanced programming knowledge. It is our vision and mission to reduce the hindrance for performing data analysis of pooled DNA GWAS through our contribution of UPDG. More importantly, we hope to promote the popularity of pooled DNA GWAS, which is a very useful research strategy.

Magnetic resonance angiography with blood-pool contrast agents: future applications

International Nuclear Information System (INIS)

Fink, C.; Goyen, M.; Lotz, J.

2007-01-01

Blood pool agents remain in the intravascular space for a longer time period. Therefore the optimal imaging window for vascular structures is widened to about 30 minutes. Gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) is the first blood-pool contrast agent approved in Europe for contrast-enhanced magnetic resonance angiography (MRA) of vessels in the abdomen, pelvis and lower extremity in adults. Other possible applications of blood-pool agents are now being considered, such as assessment of venous thromboembolism, coronary artery disease or sinus venous thrombosis. Perfusion MR imaging holds promise for detecting lung perfusion defects with higher spatial resolution and reduced scan time compared with radionuclide scintigraphy. In coronary artery disease, blood-pool agents enable a substantial increase in the quality of coronary artery imaging. Quantitative myocardial perfusion and myocardial viability seem to be possible, although modifications in protocols and sequence design are necessary for optimal results. Other novel applications of blood-pool agents include monitoring of inflammatory changes in systemic lupus erythematosus and evaluation of tumour invasion into lymph nodes and more reliable assessment of cerebral venous and sinus thrombosis. (orig.)

Magnetic resonance angiography with blood-pool contrast agents: future applications

Energy Technology Data Exchange (ETDEWEB)

Fink, C. [Univ. Hospitals, Grosshadern, Munich (Germany); Goyen, M. [Univ. Medical Center, Hamburg-Eppendorf, Hamburg (Germany); Lotz, J. [Hannover Medical School, Hannover (Germany)

2007-03-15

Blood pool agents remain in the intravascular space for a longer time period. Therefore the optimal imaging window for vascular structures is widened to about 30 minutes. Gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) is the first blood-pool contrast agent approved in Europe for contrast-enhanced magnetic resonance angiography (MRA) of vessels in the abdomen, pelvis and lower extremity in adults. Other possible applications of blood-pool agents are now being considered, such as assessment of venous thromboembolism, coronary artery disease or sinus venous thrombosis. Perfusion MR imaging holds promise for detecting lung perfusion defects with higher spatial resolution and reduced scan time compared with radionuclide scintigraphy. In coronary artery disease, blood-pool agents enable a substantial increase in the quality of coronary artery imaging. Quantitative myocardial perfusion and myocardial viability seem to be possible, although modifications in protocols and sequence design are necessary for optimal results. Other novel applications of blood-pool agents include monitoring of inflammatory changes in systemic lupus erythematosus and evaluation of tumour invasion into lymph nodes and more reliable assessment of cerebral venous and sinus thrombosis. (orig.)

Water inventory management in condenser pool of boiling water reactor

International Nuclear Information System (INIS)

Gluntz, D.M.

1996-01-01

An improved system for managing the water inventory in the condenser pool of a boiling water reactor has means for raising the level of the upper surface of the condenser pool water without adding water to the isolation pool. A tank filled with water is installed in a chamber of the condenser pool. The water-filled tank contains one or more holes or openings at its lowermost periphery and is connected via piping and a passive-type valve (e.g., squib valve) to a high-pressure gas-charged pneumatic tank of appropriate volume. The valve is normally closed, but can be opened at an appropriate time following a loss-of-coolant accident. When the valve opens, high-pressure gas inside the pneumatic tank is released to flow passively through the piping to pressurize the interior of the water-filled tank. In so doing, the initial water contents of the tank are expelled through the openings, causing the water level in the condenser pool to rise. This increases the volume of water available to be boiled off by heat conducted from the passive containment cooling heat exchangers. 4 figs

Plasma non-esterified docosahexaenoic acid is the major pool supplying the brain.

Science.gov (United States)

Chen, Chuck T; Kitson, Alex P; Hopperton, Kathryn E; Domenichiello, Anthony F; Trépanier, Marc-Olivier; Lin, Lauren E; Ermini, Leonardo; Post, Martin; Thies, Frank; Bazinet, Richard P

2015-10-29

Despite being critical for normal brain function, the pools that supply docosahexaenoic acid (DHA) to the brain are not agreed upon. Using multiple kinetic models in free-living adult rats, we first demonstrate that DHA uptake from the plasma non-esterified fatty acid (NEFA) pool predicts brain uptake of DHA upon oral administration, which enters the plasma NEFA pool as well as multiple plasma esterified pools. The rate of DHA loss by the brain is similar to the uptake from the plasma NEFA pool. Furthermore, upon acute iv administration, although more radiolabeled lysophosphatidylcholine (LPC)-DHA enters the brain than NEFA-DHA, this is due to the longer plasma half-life and exposure to the brain. Direct comparison of the uptake rate of LPC-DHA and NEFA-DHA demonstrates that uptake of NEFA-DHA into the brain is 10-fold greater than LPC-DHA. In conclusion, plasma NEFA-DHA is the major plasma pool supplying the brain.

Value of blood-pool subtraction in cardiac indium-111-labeled platelet imaging

Energy Technology Data Exchange (ETDEWEB)

Machac, J.; Vallabhajosula, S.; Goldman, M.E.; Goldsmith, S.J.; Palestro, C.; Strashun, A.; Vaquer, R.; Phillips, R.A.; Fuster, V. (Mt. Sinai Medical Center, New York, NY (USA))

1989-09-01

Blood-pool subtraction has been proposed to enhance {sup 111}In-labeled platelet imaging of intracardiac thrombi. We tested the accuracy of labeled platelet imaging, with and without blood-pool subtraction, in ten subjects with cardiac thrombi of varying age, eight with endocarditis being treated with antimicrobial therapy and ten normal controls. Imaging was performed early after labeled platelet injection (24 hr or less) and late (48 hr or more). Blood-pool subtraction was carried out. All images were graded subjectively by four experienced, blinded readers. Detection accuracy was measured by the sensitivity at three fixed levels of specificity estimated from receiver operator characteristic curve analysis and tested by three-way analysis of variance. Detection accuracy was generally improved on delayed images. Blood-pool subtraction did not improve accuracy. Although blood-pool subtraction increased detection sensitivity, this was offset by decreased specificity. For this population studied, blood-pool subtraction did not improve subjective detection of abnormal platelet deposition by 111In platelet imaging.

Value of blood-pool subtraction in cardiac indium-111-labeled platelet imaging

International Nuclear Information System (INIS)

Machac, J.; Vallabhajosula, S.; Goldman, M.E.; Goldsmith, S.J.; Palestro, C.; Strashun, A.; Vaquer, R.; Phillips, R.A.; Fuster, V.

1989-01-01

Blood-pool subtraction has been proposed to enhance 111 In-labeled platelet imaging of intracardiac thrombi. We tested the accuracy of labeled platelet imaging, with and without blood-pool subtraction, in ten subjects with cardiac thrombi of varying age, eight with endocarditis being treated with antimicrobial therapy and ten normal controls. Imaging was performed early after labeled platelet injection (24 hr or less) and late (48 hr or more). Blood-pool subtraction was carried out. All images were graded subjectively by four experienced, blinded readers. Detection accuracy was measured by the sensitivity at three fixed levels of specificity estimated from receiver operator characteristic curve analysis and tested by three-way analysis of variance. Detection accuracy was generally improved on delayed images. Blood-pool subtraction did not improve accuracy. Although blood-pool subtraction increased detection sensitivity, this was offset by decreased specificity. For this population studied, blood-pool subtraction did not improve subjective detection of abnormal platelet deposition by 111In platelet imaging

Titanium distribution in swimming pool water is dominated by dissolved species

International Nuclear Information System (INIS)

David Holbrook, R.; Motabar, Donna; Quiñones, Oscar; Stanford, Benjamin; Vanderford, Brett; Moss, Donna

2013-01-01

The increased use of titanium dioxide nanoparticles (nano-TiO 2 ) in consumer products such as sunscreen has raised concerns about their possible risk to human and environmental health. In this work, we report the occurrence, size fractionation and behavior of titanium (Ti) in a children's swimming pool. Size-fractionated samples were analyzed for Ti using ICP-MS. Total titanium concentrations ([Ti]) in the pool water ranged between 21 μg/L and 60 μg/L and increased throughout the 101-day sampling period while [Ti] in tap water remained relatively constant. The majority of [Ti] was found in the dissolved phase (<1 kDa), with only a minor fraction of total [Ti] being considered either particulate or microparticulate. Simple models suggest that evaporation may account for the observed variation in [Ti], while sunscreen may be a relevant source of particulate and microparticule Ti. Compared to diet, incidental ingestion of nano-Ti from swimming pool water is minimal. -- Highlights: •Total titanium concentrations in unfiltered swimming pool water ranged between 21 and 60 μg/L. •Evaporation of the swimming pool water is suspected of causing a temporal increase in [Ti]. •The vast majority of Ti is found in the dissolved phase (<1 kD). •Swimming pools are not a significant Ti source for human exposure via ingestion. -- In children's swimming pool water, the majority of titanium is found in the dissolved phase

Environmental assessment, K Pool fish rearing, Hanford Site, Richland, Washington

International Nuclear Information System (INIS)

1996-12-01

The US Department of Energy (DOE) has a need to respond to a request to lease facilities at the Hanford Site 100-KE and 100-KW filter plant pools (K Pools) for fish rearing activities. These fish rearing activities would be: (1) business ventures with public and private funds and (2) long-term enhancement and supplementation programs for game fish populations in the Columbia River Basin. The proposed action is to enter into a use permit or lease agreement with the YIN or other parties who would rear fish in the 100-K Area Pools. The proposed action would include necessary piping, pump, and electrical upgrades of the facility; cleaning and preparation of the pools; water withdrawal from the Columbia River, and any necessary water or wastewater treatment; and introduction, rearing and release of fish. Future commercial operations may be included

Environmental assessment, K Pool fish rearing, Hanford Site, Richland, Washington

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-01

The US Department of Energy (DOE) has a need to respond to a request to lease facilities at the Hanford Site 100-KE and 100-KW filter plant pools (K Pools) for fish rearing activities. These fish rearing activities would be: (1) business ventures with public and private funds and (2) long-term enhancement and supplementation programs for game fish populations in the Columbia River Basin. The proposed action is to enter into a use permit or lease agreement with the YIN or other parties who would rear fish in the 100-K Area Pools. The proposed action would include necessary piping, pump, and electrical upgrades of the facility; cleaning and preparation of the pools; water withdrawal from the Columbia River, and any necessary water or wastewater treatment; and introduction, rearing and release of fish. Future commercial operations may be included.

76 FR 64085 - Post-2014 Resource Pool-Loveland Area Projects, Final Power Allocation

Science.gov (United States)

2011-10-17

... Resource Pool; Loveland Area Projects, General Eligibility Criteria. The resource pool for capacity and... transmission in Kansas. Final allocation of the Post-2014 Resource Pool; Loveland Area Projects, is contingent...

Numerical simulation of pool boiling of a Lennard-Jones liquid

KAUST Repository

Inaoka, Hajime; Ito, Nobuyasu

2013-01-01

We performed a numerical simulation of pool boiling by a molecular dynamics model. In the simulation, a liquid composed of Lennard-Jones particles in a uniform gravitational field is heated by a heat source at the bottom of the system. The model successfully reproduces the change in regimes of boiling from nucleate boiling to film boiling with the increase of the heat source temperature. We present the pool boiling curve by the model, whose general behavior is consistent with those observed in experiments of pool boiling. © 2013 Elsevier B.V. All rights reserved.

Numerical simulation of pool boiling of a Lennard-Jones liquid

KAUST Repository

Inaoka, Hajime

2013-09-01

We performed a numerical simulation of pool boiling by a molecular dynamics model. In the simulation, a liquid composed of Lennard-Jones particles in a uniform gravitational field is heated by a heat source at the bottom of the system. The model successfully reproduces the change in regimes of boiling from nucleate boiling to film boiling with the increase of the heat source temperature. We present the pool boiling curve by the model, whose general behavior is consistent with those observed in experiments of pool boiling. © 2013 Elsevier B.V. All rights reserved.

One component, volume heated, boiling pool thermohydraulics

International Nuclear Information System (INIS)

Bede, M.; Perret, C.; Pretrel, H.; Seiler, J.M.

1993-01-01

Prior work on boiling pools provided heat exchange correlations valid for bubbly flow with laminar or turbulent boundary layers. New experiments performed with water (SEBULON) and UO 2 (SCARABEE BF2) in a churn-turbulent flow configuration show unexpected heat flux distributions for which the maximum heat flux may be situated well below the pool surface. The origin of this behaviour is attributed to condensation effects, very unstable boundary layer flow and surface oscillation. A calculation model is discussed which permits to approach the experimental heat flux distribution with reasonable accuracy. (authors). 7 figs., 2 appendix., 14 refs

Volume-heated boiling pool behavior and application to transition phase accident conditions

International Nuclear Information System (INIS)

Ginsberg, T.; Jones, O.C. Jr.; Chen, J.C.

1978-01-01

Observations of two-phase flow fields in volume-heated boiling pools are reported. Photographic observations, together with pool-average void fraction measurements are presented. Flow regime transition criterial derived from the measurements are discussed. The churn-turbulent flow regime was the dominant regime for superficial vapor velocity. Within this range of conditions, a churn-turbulent drift flux model provides a reasonable prediction of the pool-average void fraction data. The results of the experiment and analysis are extrapolated to transition phase conditions. It is shown that intense pool boil-up could occur where the pool-average void fraction would be greater than 0.6 for steel vaporization rates equivalent to power levels greater than one percent of nominal LMFBR power density. (author)

AUS burnup module CHAR and the associated data pool

International Nuclear Information System (INIS)

Robinson, G.S.

1975-12-01

The CHAR module of the AUS reactor neutronics scheme solves the multiregion nuclide depletion equations using an analytic method. The module obtains cross section, flux and geometry data from AUS data pools, and uses the STATUS data pool which has been designed for the storage of nuclide compositions, spatial smearing factors and other miscellaneous information. (author)

Inter-progenitor pool wiring: An evolutionarily conserved strategy that expands neural circuit diversity.

Science.gov (United States)

Suzuki, Takumi; Sato, Makoto

2017-11-15

Diversification of neuronal types is key to establishing functional variations in neural circuits. The first critical step to generate neuronal diversity is to organize the compartmental domains of developing brains into spatially distinct neural progenitor pools. Neural progenitors in each pool then generate a unique set of diverse neurons through specific spatiotemporal specification processes. In this review article, we focus on an additional mechanism, 'inter-progenitor pool wiring', that further expands the diversity of neural circuits. After diverse types of neurons are generated in one progenitor pool, a fraction of these neurons start migrating toward a remote brain region containing neurons that originate from another progenitor pool. Finally, neurons of different origins are intermingled and eventually form complex but precise neural circuits. The developing cerebral cortex of mammalian brains is one of the best examples of inter-progenitor pool wiring. However, Drosophila visual system development has revealed similar mechanisms in invertebrate brains, suggesting that inter-progenitor pool wiring is an evolutionarily conserved strategy that expands neural circuit diversity. Here, we will discuss how inter-progenitor pool wiring is accomplished in mammalian and fly brain systems. Copyright © 2017 Elsevier Inc. All rights reserved.

Impacts of exotic mangroves and mangrove control on tide pool fish assemblages

Science.gov (United States)

Richard A. MacKenzie; Cailtin L. Kryss

2013-01-01

Fish were sampled from tide pools in Hawaii to determine how exotic mangroves Rhizophora mangle and the use of herbicides to chemically eradicate them are impacting tide pool fish assemblages. Ecological parameters were compared among mangrove-invaded, native vegetated, and non-vegetated tide pools before and after mangroves had been chemically...

Experimental investigation on the weld pool formation process in plasma keyhole arc welding

Science.gov (United States)

Van Anh, Nguyen; Tashiro, Shinichi; Van Hanh, Bui; Tanaka, Manabu

2018-01-01

This paper seeks to clarify the weld pool formation process in plasma keyhole arc welding (PKAW). We adopted, for the first time, the measurement of the 3D convection inside the weld pool in PKAW by stereo synchronous imaging of tungsten tracer particles using two sets of x-ray transmission systems. The 2D convection on the weld pool surface was also measured using zirconia tracer particles. Through these measurements, the convection in a wide range of weld pools from the vicinity of the keyhole to the rear region was successfully visualized. In order to discuss the heat transport process in a weld pool, the 2D temperature distribution on the weld pool surface was also measured by two-color pyrometry. The results of the comprehensive experimental measurement indicate that the shear force due to plasma flow is found to be the dominant driving force in the weld pool formation process in PKAW. Thus, heat transport in a weld pool is considered to be governed by two large convective patterns near the keyhole: (1) eddy pairs on the surface (perpendicular to the torch axis), and (2) eddy pairs on the bulk of the weld pool (on the plane of the torch). They are formed with an equal velocity of approximately 0.35 m s-1 and are mainly driven by shear force. Furthermore, the flow velocity of the weld pool convection becomes considerably higher than that of other welding processes, such as TIG welding and GMA welding, due to larger plasma flow velocity.

A hierarchic sustainability dashboard to evaluate logistics pooling

OpenAIRE

Morana, Joëlle; Gonzalez-Feliu, Jesus

2014-01-01

Logistics pooling is now a major challenge in supply chain management, though it remains a little known activity in which the different actors involved use different approaches whose objectives are not always the same and with sometimes conflicting standpoints. This purpose of this article is to define, on the basis of a detailed analysis of the literature, a grid for interpreting and a dashboard for evaluating the sustainable performance of pooled delivery systems. Firstly, an analysis of th...

Models for Pooled Time-Series Cross-Section Data

Directory of Open Access Journals (Sweden)

Lawrence E Raffalovich

2015-07-01

Full Text Available Several models are available for the analysis of pooled time-series cross-section (TSCS data, defined as “repeated observations on fixed units” (Beck and Katz 1995. In this paper, we run the following models: (1 a completely pooled model, (2 fixed effects models, and (3 multi-level/hierarchical linear models. To illustrate these models, we use a Generalized Least Squares (GLS estimator with cross-section weights and panel-corrected standard errors (with EViews 8 on the cross-national homicide trends data of forty countries from 1950 to 2005, which we source from published research (Messner et al. 2011. We describe and discuss the similarities and differences between the models, and what information each can contribute to help answer substantive research questions. We conclude with a discussion of how the models we present may help to mitigate validity threats inherent in pooled time-series cross-section data analysis.

Evaluation of Decontamination Factor of Aerosol in Pool Scrubber according to Bubble Shape and Size

Energy Technology Data Exchange (ETDEWEB)

Jo, Hyun Joung; Ha, Kwang Soon; Jang, Dong Soon [KAERI, Daejeon (Korea, Republic of)

2016-05-15

The scrubbing pool could play an important role in the wet type FCVS because a large amount of aerosol is captured in the water pool. The pool scrubbing phenomena have been modelled and embedded in several computer codes, such as SPARC (Suppression Pool Aerosol Removal Code), BUSCA (BUbble Scrubbing Algorithm) and SUPRA (Suppression Pool Retention Analysis). These codes aim at simulating the pool scrubbing process and estimating the decontamination factors (DFs) of the radioactive aerosol and iodine gas in the water pool, which is defined as the ratio of initial mass of the specific radioactive material to final massy after passing through the water pool. The pool scrubbing models were reviewed and an aerosol scrubbing code has been prepared to calculate decontamination factor through the pool. The developed code has been verified using the experimental results and parametric studies the decontamination factor according to bubble shape and size. To evaluate the decontamination factor more accurate whole pool scrubber phenomena, the code was improved to consider the variety shape and size of bubbles. The decontamination factor were largely evaluated in ellipsoid bubble rather than in sphere bubble. The pool scrubbing models will be enhanced to apply more various model such as aerosol condensation of hygroscopic. And, it is need to experiment to measure to bubble shape and size distribution in pool to improve bubble model.

Heat and Fission Product Transport in a Molten U-Zr-O Pool With Crust

International Nuclear Information System (INIS)

Yun, J.I.; Suh, K.Y.; Kang, C.S.

2002-01-01

Heat transfer and fluid flow in a molten pool are influenced by internal volumetric heat generated from the radioactive decay of fission product species retained in the pool. The pool superheat is determined based on the overall energy balance that equates the heat production rate to the heat loss rate. Decay heat of fission products in the pool was estimated by product of the mass concentration and energy conversion factor of each fission product. For the calculation of heat generation rate in the pool, twenty-nine elements were chosen and classified by their chemical properties. The mass concentration of a fission product is obtained from released fraction and the tabular output of the ORIGEN 2 code. The initial core and pool inventories at each time can also be estimated using ORIGEN 2. The released fraction of each fission product is calculated based on the bubble dynamics and mass transport. Numerical analysis was performed for the TMI-2 accident. The pool is assumed to be a partially filled hemispherical geometry and the change of pool geometry during the numerical calculation was neglected. Results of the numerical calculation revealed that the peak temperature of the molten pool significantly decreased and most of the volatile fission products were released from the molten pool during the accident. (authors)

Development and validation of effective models for simulation of stratification and mixing phenomena in a pool of water

Energy Technology Data Exchange (ETDEWEB)

Li, H.; Kudinov, P.; Villanueva, W. (Royal Institute of Technology (KTH). Div. of Nuclear Power Safety (Sweden))

2011-06-15

This work pertains to the research program on Containment Thermal-Hydraulics at KTH. The objective is to evaluate and improve performance of methods, which are used to analyze thermal-hydraulics of steam suppression pools in a BWR plant under different abnormal transient and accident conditions. The pressure suppression pool was designed to have the capability as a heat sink to cool and condense steam released from the core vessel and/or main steam line during loss of coolant accident (LOCA) or opening of safety relief valve in normal operation of BWRs. For the case of small flow rates of steam influx, thermal stratification could develop on the part above the blowdown pipe exit and significantly impede the pool's pressure suppression capacity. Once steam flow rate increases significantly, momentum introduced by the steam injection and/or periodic expansion and collapse of large steam bubbles due to direct contact condensation can destroy stratified layers and lead to mixing of the pool water. We use CFD-like model of the general purpose thermal-hydraulic code GOTHIC for addressing the issues of stratification and mixing in the pool. In the previous works we have demonstrated that accurate and computationally efficient prediction of the pool thermal-hydraulics in the scenarios with transition between thermal stratification and mixing, presents a computational challenge. The reason is that direct contact condensation phenomena, which drive oscillatory motion of the water in the blowdown pipes, are difficult to simulate with original GOTHIC models because of appearance of artificial oscillations due to numerical disturbances. To resolve this problem we propose to model the effect of steam injection on the mixing and stratification with the Effective Heat Source (EHS) model and the Effective Momentum Source (EMS) model. We use POOLEX/PPOOLEX experiment (Lappeenranta University of Technology in Finland), in order to (a) quantify errors due to GOTHIC

Development and validation of effective models for simulation of stratification and mixing phenomena in a pool of water

International Nuclear Information System (INIS)

Li, H.; Kudinov, P.; Villanueva, W.

2011-06-01

This work pertains to the research program on Containment Thermal-Hydraulics at KTH. The objective is to evaluate and improve performance of methods, which are used to analyze thermal-hydraulics of steam suppression pools in a BWR plant under different abnormal transient and accident conditions. The pressure suppression pool was designed to have the capability as a heat sink to cool and condense steam released from the core vessel and/or main steam line during loss of coolant accident (LOCA) or opening of safety relief valve in normal operation of BWRs. For the case of small flow rates of steam influx, thermal stratification could develop on the part above the blowdown pipe exit and significantly impede the pool's pressure suppression capacity. Once steam flow rate increases significantly, momentum introduced by the steam injection and/or periodic expansion and collapse of large steam bubbles due to direct contact condensation can destroy stratified layers and lead to mixing of the pool water. We use CFD-like model of the general purpose thermal-hydraulic code GOTHIC for addressing the issues of stratification and mixing in the pool. In the previous works we have demonstrated that accurate and computationally efficient prediction of the pool thermal-hydraulics in the scenarios with transition between thermal stratification and mixing, presents a computational challenge. The reason is that direct contact condensation phenomena, which drive oscillatory motion of the water in the blowdown pipes, are difficult to simulate with original GOTHIC models because of appearance of artificial oscillations due to numerical disturbances. To resolve this problem we propose to model the effect of steam injection on the mixing and stratification with the Effective Heat Source (EHS) model and the Effective Momentum Source (EMS) model. We use POOLEX/PPOOLEX experiment (Lappeenranta University of Technology in Finland), in order to (a) quantify errors due to GOTHIC's physical models

Greenland Tidal Pools as Hot Spots for Ecosystem Metabolism and Calcification

KAUST Repository

Duarte, Carlos M.; Krause-Jensen, Dorte

2018-01-01

The hypothesis that Arctic tidal pools provide environmental conditions suitable for calcifiers during summer, thereby potentially providing refugia for calcifiers in an acidifying Arctic Ocean, was tested on the basis of measurements conducted during two midsummers (2014 and 2016) in tidal pools colonised by a community composed of macroalgae and calcifiers in Disko Bay, Greenland (69° N). The tidal pools exhibited steep diurnal variations in temperature from a minimum of about 6 °C during the night to a maximum of almost 18 °C in the afternoon, while the temperature of the surrounding shore water was much lower, typically in the range 3 to 8 °C. O2 concentrations in the tidal pools were elevated relative to those in the adjacent open waters, by up to 11 mg O2 L−1, and exhibited heavy super-saturation (up to > 240%) during daytime emersion, reflecting intense and sustained photosynthetic rates of the tidal macroalgae. The intense photosynthetic activity of the seaweeds resulted in the drawdown of pCO2 concentrations in the pools during the day to levels down to average (±SE) values of 66 ± 18 ppm, and a minimum recorded value of 14.7 ppm, corresponding to pH levels as high as 8.69 ± 0.08, as compared to CO2 levels of 256 ± 4 and pH levels of 8.14 ± 0.01 in the water flooding the pools during high tide. The corresponding Ωarag reached 5.04 ± 0.49 in the pools as compared to 1.55 ± 0.02 in the coastal waters flooding the pools. Net calcification averaged 9.6 ± 5.6 μmol C kg−1 h−1 and was strongly and positively correlated with calculated net ecosystem production rates, which averaged 27.5 ± 8.6 μmol C kg−1 h−1. Arctic tidal pools promote intense metabolism, creating conditions suitable for calcification during the Arctic summer, and can, therefore, provide refugia from ocean acidification to vulnerable calcifiers as extended periods of continuous light during summer are conducive to suitable conditions

Greenland Tidal Pools as Hot Spots for Ecosystem Metabolism and Calcification

KAUST Repository

Duarte, Carlos M.

2018-01-18

The hypothesis that Arctic tidal pools provide environmental conditions suitable for calcifiers during summer, thereby potentially providing refugia for calcifiers in an acidifying Arctic Ocean, was tested on the basis of measurements conducted during two midsummers (2014 and 2016) in tidal pools colonised by a community composed of macroalgae and calcifiers in Disko Bay, Greenland (69° N). The tidal pools exhibited steep diurnal variations in temperature from a minimum of about 6 °C during the night to a maximum of almost 18 °C in the afternoon, while the temperature of the surrounding shore water was much lower, typically in the range 3 to 8 °C. O2 concentrations in the tidal pools were elevated relative to those in the adjacent open waters, by up to 11 mg O2 L−1, and exhibited heavy super-saturation (up to > 240%) during daytime emersion, reflecting intense and sustained photosynthetic rates of the tidal macroalgae. The intense photosynthetic activity of the seaweeds resulted in the drawdown of pCO2 concentrations in the pools during the day to levels down to average (±SE) values of 66 ± 18 ppm, and a minimum recorded value of 14.7 ppm, corresponding to pH levels as high as 8.69 ± 0.08, as compared to CO2 levels of 256 ± 4 and pH levels of 8.14 ± 0.01 in the water flooding the pools during high tide. The corresponding Ωarag reached 5.04 ± 0.49 in the pools as compared to 1.55 ± 0.02 in the coastal waters flooding the pools. Net calcification averaged 9.6 ± 5.6 μmol C kg−1 h−1 and was strongly and positively correlated with calculated net ecosystem production rates, which averaged 27.5 ± 8.6 μmol C kg−1 h−1. Arctic tidal pools promote intense metabolism, creating conditions suitable for calcification during the Arctic summer, and can, therefore, provide refugia from ocean acidification to vulnerable calcifiers as extended periods of continuous light during summer are conducive to suitable conditions

Dynamics of inorganic nutrients in intertidal sediments: porewater, exchangeable and intracellular pools

Directory of Open Access Journals (Sweden)

Emilio eGarcia-Robledo

2016-05-01

Full Text Available The study of inorganic nutrients dynamics in shallow sediments usually focuses on two main pools: the porewater (PW nutrients and the exchangeable (EX ammonium and phosphate. Recently, it has been found that microphytobenthos (MPB and other microorganisms can accumulate large amounts of nutrients intracellularly (IC, highlighting the biogeochemical importance of this nutrient pool. Storing nutrients could support the growth of autotrophs when nutrients are not available, and could also provide alternative electron acceptors for dissimilatory processes such as nitrate reduction. Here, we studied the magnitude and relative importance of these three nutrient pools (PW, IC and EX and their relation to chlorophylls (used as a proxy for MPB abundance and organic matter (OM contents in an intertidal mudflat of Cadiz Bay (Spain. MPB was localized in the first 4 mm of the sediment and showed a clear seasonal pattern; highest chlorophylls content was found during autumn and lowest during spring-summer. The temporal and spatial distribution of nutrients pools and MPB were largely correlated. Ammonium was higher in the IC and EX fractions, representing on average 59 and 37% of the total ammonium pool, respectively. Similarly, phosphate in the IC and EX fractions accounted on average for 40 and 31% of the total phosphate pool, respectively. Nitrate in the PW was low, suggesting low nitrification activity and rapid consumption. Nitrate accumulated in the IC pool during periods of moderate MPB abundance, being up to 66% of the total nitrate pool, whereas it decreased when chlorophyll concentration peaked likely due to a high nitrogen demand. EX-Nitrate accounted for the largest fraction of total sediment nitrate, 66% on average. The distribution of EX-Nitrate was significantly correlated with chlorophyll and OM, which probably indicates a relation of this pool to an increased availability of sites for ionic adsorption. This EX-Nitrate pool could represent an

7 CFR 1126.7 - Pool plant.

Science.gov (United States)

2010-01-01

... excluded from the supply plant's shipments in computing the plant's shipping percentage. (d) A plant... part, or the plant has automatic pooling status under the other Federal order; and (7) That portion of...

Equilibrium blood pool scanning in the evaluation of hemophilic arthropathy

International Nuclear Information System (INIS)

Spies, S.; Green, D.; Rana, N.A.; Milgram, J.W.; Mintzer, R.

1978-01-01

Arthropathy was evaluated in six patients with severe hemophilia (factor VIII<1%) using the technique of blood pool scanning. Employing an in vivo method for erythrocyte labelling with technetium-99m, a dynamic perfusion sequence was obtained using a scintillation camera over the joint(s) to be examined. Subsequently, equilibrium blood pool images of the joints were obtained to determine regional blood volume. In young patients with repeated episodes of acute hemarthrosis, increased vascularity and increased blood pool in the affected joints were demonstrated. In older patients with fixed, contracted joints and degenerative arthropathy, vascularity and regional blood volume were not abnormal. Blood pool scanning is a safe, non-invasive technique that augments the clinical and radiographic examination of the joints. The method is helpful in distinguishing acute joint bleeding from chronic synovitis and arthritis, and may prove useful in selecting patients for synovectomy. (author)

Pump/heat exchanger assembly for pool-type reactor

International Nuclear Information System (INIS)

Nathenson, R.D.; Slepian, R.M.

1987-01-01

A heat exchanger and pump assembly comprising a heat exchanger including a housing for defining an annularly shaped cavity and supporting therein a plurality of heat transfer tubes. A pump is disposed beneath the heat exchanger and is comprised of a plurality of flow couplers disposed in a circular array. Each flow coupler is comprised of a pump duct for receiving a first electrically conductive fluid, i.e. the primary liquid metal, from a pool thereof, and a generator duct for receiving a second electrically conductive fluid, i.e. the intermediate liquid metal. The primary liquid metal is introduced from the reactor pool into the top, inlet ends of the tubes, flowing downward therethrough to be discharged from the tubes' bottom ends directly into the reactor pool. The primary liquid metal is variously introduced into the pump ducts directly from the reactor pool, either from the bottom or top end of the flow coupler. The intermediate fluid introduced into the generator ducts via the inlet duct and inlet plenum and after leaving the generator ducts passes through the annular cavity of the exchanger to cool the primary liquid in the tubes. The annular magnetic field of the pump is produced by a circular array of electromagnets having hollow windings cooled by a flow of the intermediate metal. (author)

Convective cooling in a pool-type research reactor

Science.gov (United States)

Sipaun, Susan; Usman, Shoaib

2016-01-01

A reactor produces heat arising from fission reactions in the nuclear core. In the Missouri University of Science and Technology research reactor (MSTR), this heat is removed by natural convection where the coolant/moderator is demineralised water. Heat energy is transferred from the core into the coolant, and the heated water eventually evaporates from the open pool surface. A secondary cooling system was installed to actively remove excess heat arising from prolonged reactor operations. The nuclear core consists of uranium silicide aluminium dispersion fuel (U3Si2Al) in the form of rectangular plates. Gaps between the plates allow coolant to pass through and carry away heat. A study was carried out to map out heat flow as well as to predict the system's performance via STAR-CCM+ simulation. The core was approximated as porous media with porosity of 0.7027. The reactor is rated 200kW and total heat density is approximately 1.07+E7 Wm-3. An MSTR model consisting of 20% of MSTR's nuclear core in a third of the reactor pool was developed. At 35% pump capacity, the simulation results for the MSTR model showed that water is drawn out of the pool at a rate 1.28 kg s-1 from the 4" pipe, and predicted pool surface temperature not exceeding 30°C.

Validation analysis of pool fire experiment (Run-F7) using SPHINCS code

International Nuclear Information System (INIS)

Yamaguchi, Akira; Tajima, Yuji

1998-04-01

SPHINCS (Sodium Fire Phenomenology IN multi-Cell System) code has been developed for the safety analysis of sodium fire accident in a Fast Breeder Reactor. The main features of the SPHINCS code with respect to the sodium pool fire phenomena are multi-dimensional modeling of the thermal behavior in sodium pool and steel liner, modeling of the extension of sodium pool area based on the sodium mass conservation, and equilibrium model for the chemical reaction of pool fire on the flame sheet at the surface of sodium pool during. Therefore, the SPHINCS code is capable of temperature evaluation of the steel liner in detail during the small and/or medium scale sodium leakage accidents. In this study, Run-F7 experiment in which the sodium leakage rate is 11.8 kg/hour has been analyzed. In the experiment the diameter of the sodium pool is approximately 60 cm and the maximum steel liner temperature was 616 degree C. The analytical results tell us the agreement between the SPHINCS analysis and the experiment is excellent with respect to the time history and spatial distribution of the liner temperature, sodium pool extension behavior, as well as atmosphere gas temperature. It is concluded that the pool fire modeling of the SPHINCS code has been validated for this experiment. The SPHINCS code is currently applicable to the sodium pool fire phenomena and the temperature evaluation of the steel liner. The experiment series are continued to check some parameters, i.e., sodium leakage rate and the height of sodium leakage. Thus, the author will analyze the subsequent experiments to check the influence of the parameters and applies SPHINCS to the sodium fire consequence analysis of fast reactor. (author)

Analysis of radiation shields of BNPP spent fuel pool

International Nuclear Information System (INIS)

Ayoobian, N.; Hadad, K.; Nematollahi, M. R.

2007-01-01

Radioactive protection is one of the most important subjects in nuclear power plants safety. Analysis of BNPP spent fuel pool shielding , as a main source of energetic γ-rays was the main goal of this project. Firstly, we simulated the reactor core using WIMSD-4 neutronic code and the amount of fission product in the fuel assembly (FA) was calculated during the reactor operation. Then, by obtaining the results from the previous calculation and by using MCNP4C nuclear code , the intensity of γ-rays was obtained in layers of spent fuel pool shields. The results have shown that no significant γ-rays passed through these shields. Finally, an accident and resulting exposure dose above the pool was analyzed

Analyzing data distribution on disk pools for dCache

Energy Technology Data Exchange (ETDEWEB)

Halstenberg, S; Jung, C; Ressmann, D [Forschungszentrum Karlsruhe, Steinbuch Centre for Computing, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

2010-04-01

Most Tier-1 centers of LHC Computing Grid are using dCache as their storage system. dCache uses a cost model incorporating CPU and space costs for the distribution of data on its disk pools. Storage resources at Tier-1 centers are usually upgraded once or twice a year according to given milestones. One of the effects of this procedure is the accumulation of heterogeneous hardware resources. For a dCache system, a heterogeneous set of disk pools complicates the process of weighting CPU and space costs for an efficient distribution of data. In order to evaluate the data distribution on the disk pools, the distribution is simulated in Java. The results are discussed and suggestions for improving the weight scheme are given.

Removal of volatile iodine from gas bubbles rising in water pools: review and assessment of pool scrubbing codes

Energy Technology Data Exchange (ETDEWEB)

Polo, J; Herranz, L E; Peyres, V; Escudero, M [CIEMAT, Nuclear Technology Institute, Madrid (Spain)

1996-12-01

During a hypothetical nuclear reactor accident with core damage the fission products released from the degrading fuel bundles often pass through aqueous beds before entering the containment, mitigating in part the source term. Several computer codes have been developed for predicting the fission product and aerosols removal in pool scrubbing scenarios. In addition to particle removal, these codes simulate the retention of some volatile iodine compounds. In this work a review of volatile iodine removal models included in SPARC and BUSCA codes is presented. Besides, the results and discussions of a validation of both codes against the available experimental data are summarized. SPARC and BUSCA codes model the diffusion of iodine toward the bubble interface by using the film penetration theory, which assumes a double layer gas-liquid at the interface. However, there are some differences between the two models, mainly related to the boundary conditions in the aqueous volume for the diffusion of molecular iodine. In SPARC, a set of fast reactions in the liquid phase control both the molecular iodine concentration in the pool and the partition coefficient of iodine at the interface. Thus, the aqueous chemistry plays an important role in the boundary conditions for the diffusion process. On the contrary, the BUSCA model has no chemical considerations at all, and assumes a null iodine concentration in the water bulk. Several sensitivity studies have been made in order to weight the effect of these differences. The variables examined in these studies were the pool temperature and the incoming iodine concentration in the pool. Additionally, sensitivity studies focused on the steam mass fraction of the injected gas were performed to study the effect of the different approach of both models for the condensation process. The results showed a different sensitivity of SPARC and BUSCA to the incoming concentration. (author) 5 tabs., 26 refs.

7 CFR 1001.7 - Pool plant.

Science.gov (United States)

2010-01-01

... excluded from the supply plant's shipments in computing the percentages in paragraphs (c)(1) and (2) of... plant has automatic pooling status under the other Federal order. [64 FR 47954, Sept. 1, 1999, as...

Disinfection by-product formation of UV treated swimming pool water

DEFF Research Database (Denmark)

Spiliotopoulou, Aikaterini; Hansen, Kamilla Marie Speht; Andersen, Henrik Rasmus

2015-01-01

Water samples from 3 indoor swimming pool facilities were tested to evaluate UV-induced effects on swimming pool water chemistry. Concentration change of several DBPs was investigated in experiments including medium pressure UV treatment with and without chlorine and post-UV chlorination. Post-UV...

Fuel assembly storage pool

International Nuclear Information System (INIS)

Hiranuma, Hiroshi.

1976-01-01

Object: To remove limitation of the number of storage of fuel assemblies to increase the number of storage thereof so as to relatively reduce the water depth required for shielding radioactive rays. Structure: Fuel assembly storage rack containers for receiving a plurality of spent fuel assembly racks are stacked in multi-layer fashion within a storage pool filled with water for shielding radioactive rays and removing heat. (Furukawa, Y.)

Determination of isotopomers in pools of molecules with polyisotopic elements

International Nuclear Information System (INIS)

Zyakun, A.M.; Brenninkmeijer, C.A.M.

2002-01-01

Polyisotopic element atoms that are present in a molecule form a pool of isotopomer molecules. Mono- and polyisotopomers are distinguished depending on the quantity of atoms of polyisotopic elements. Methodical approaches have been considered for the quantitative determination of the isotope composition of an element included in mono- and polyisotopic molecules. A possibility of the equally probable (homogeneous) and non-equally probable (non-homogeneous) distribution of isotopes of a polyisotopic element, the atoms of which have different positions in the molecule of polyisotopomer, has been shown. Factors disturbing the homogeneous distribution of isotopes of the element in the polyisotopomer pool have been revealed. When a polyisotopomer is involved in a mass-dependent process or reaction, the homogeneity of isotope distribution of the element is disturbed both in the residual and newly formed pools of polyisotopomer. By the example of CO 2 (polyisotopomer by oxygen) it has been shown that one can judge of the history of the analyzed pool formation by distribution of oxygen isotopes within this pool. The isotope content in the oxygen sites of polyisotopomer is a diagnostic feature of CO 2 involvement in the efflux from a reservoir or influx to the analyzed reservoir from an external source. (author)

Development of INSPCT-S for inspection of spent fuel pool

Energy Technology Data Exchange (ETDEWEB)

Walters, W.; Haghighat, A. [Nuclear Engineering Program, Mechanical Engineering Dept., Virginia Tech., Blacksburg, VA 24061 (United States); Sitaraman, S.; Ham, Y. [Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA 94550 (United States)

2011-07-01

In this paper, we discuss an accurate and fast software tool (INSPCT-S, Inspection of Nuclear Spent fuel-Pool Calculation Tool, version Spreadsheet) developed for calculation of the response of fission chambers placed in a spent fuel pool, such as Atucha-I. INSPCT-S is developed for identification of suspicious regions of the pool that may have missing or substitute assemblies. INSPCT-S uses a hybrid algorithm based on the adjoint function methodology. The neutron source is comprised of spontaneous fission, ({alpha}, n) interactions, and subcritical multiplication. The former is evaluated using the ORIGEN-ARP code, and the latter is obtained with the fission matrix (FM) formulation. The FM coefficients are determined using the MCNP Monte Carlo code, and the importance function is determined using the PENTRAN 3-D parallel Sn code. Three databases for the neutron source, FM elements, and adjoint flux are prepared as functions of different parameters including burnup, cooling time, enrichment, and pool lattice size. INSPCT-S uses the aforementioned databases and systems of equations to calculate detector responses, which are subsequently compared with normalized experimental data. If this comparison is not satisfied, INSPCT-S utilizes color coding to identify the suspicious regions of a spent fuel pool. (authors)

Mathematical modelling and simulation of the thermal performance of a solar heated indoor swimming pool

OpenAIRE

Mančić Marko V.; Živković Dragoljub S.; Milosavljević Peđa M.; Todorović Milena N.

2014-01-01

Buildings with indoor swimming pools have a large energy footprint. The source of major energy loss is the swimming pool hall where air humidity is increased by evaporation from the pool water surface. This increases energy consumption for heating and ventilation of the pool hall, fresh water supply loss and heat demand for pool water heating. In this paper, a mathematical model of the swimming pool was made to assess energy demands of an indoor swimming po...

Measure Guideline: Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

Energy Technology Data Exchange (ETDEWEB)

Hunt, A.; Easley, S.

2012-05-01

The report evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provide a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

Spent fuel pool thermal-hydraulic analysis using RELAP5-3D

Energy Technology Data Exchange (ETDEWEB)

Ramos, M. C.; Fernandes, G.H.N.; Costa, A.L.; Pereira, F.; Pereira, C., E-mail: marc5663@gmail.com, E-mail: ghnfernandes@pq.cnpq.br, E-mail: claubia@nuclear.ufmg.br, E-mail: antonella@nuclear.ufmg.br [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

2017-07-01

In order to analyze the thermo-hydraulic behavior of spent fuel pools, and taking as reference a hypothetic PWR nuclear plant, a model of RELAP-3D for a spent fuel pool has been built. This model has been used to simulate a loss of coolant in SPF. This study focuses on the loss of coolant flow accident in spent fuel storage pool which is modelled by using RELAP5-3D code to observe the coolant level reduction and fuel uncovery because of decay heat generation of the spent fuel in the pool. The results have been compared with the available data. The developed model demonstrated that the RELAP5-3D is capable of reproduce the thermal behavior of SPF in a transient scenario. (author)

Condensation of vapor bubble in subcooled pool

Science.gov (United States)

Horiuchi, K.; Koiwa, Y.; Kaneko, T.; Ueno, I.

2017-02-01

We focus on condensation process of vapor bubble exposed to a pooled liquid of subcooled conditions. Two different geometries are employed in the present research; one is the evaporation on the heated surface, that is, subcooled pool boiling, and the other the injection of vapor into the subcooled pool. The test fluid is water, and all series of the experiments are conducted under the atmospheric pressure condition. The degree of subcooling is ranged from 10 to 40 K. Through the boiling experiment, unique phenomenon known as microbubble emission boiling (MEB) is introduced; this phenomenon realizes heat flux about 10 times higher than the critical heat flux. Condensation of the vapor bubble is the key phenomenon to supply ambient cold liquid to the heated surface. In order to understand the condensing process in the MEB, we prepare vapor in the vapor generator instead of the evaporation on the heated surface, and inject the vapor to expose the vapor bubble to the subcooled liquid. Special attention is paid to the dynamics of the vapor bubble detected by the high-speed video camera, and on the enhancement of the heat transfer due to the variation of interface area driven by the condensation.

A novel PCR-based marker for identifying Ns chromosomes in wheat-Psathyrostachys huashanica Keng derivative lines

Directory of Open Access Journals (Sweden)

J. Wang

2013-10-01

Full Text Available Psathyrostachys huashanica Keng is an endangered species that is endemic to China, which provides an important gene pool for wheat improvement. We developed a quick and reliable PCR-based diagnostic assay to accurately and efficiently detect P. huashanica DNA sequences from introgression lines, which was based on a species-specific marker derived from genomic DNA. The 900-bp PCR-amplified band used as a P. huashanica-specific RAPD marker was tested with 21 different plant species and was converted into a sequence-characterized amplified region (SCAR marker by cloning and sequencing the selected fragments (pHs11. This SCAR marker, which was designated as RHS23, could clearly distinguish the presence of P. huashanica DNA repetitive sequences in wheat-P. huashanica derivative lines. The specificity of the marker was validated using 21 different plant species and a complete set of wheat-P. huashanica disomic addition lines (1Ns–7Ns, 2n=44=22II. This specific sequence targeted the Ns genome of P. huashanica and it was present in all the seven P. huashanica chromosomes. Therefore, this SCAR marker is specific for P. huashanica chromosomes and may be used in the identification of alien repetitive sequences in large gene pools. This diagnostic PCR assay for screening the target genetic material may play a key role in marker-assisted selective breeding programs.

Reracking Possibilities of the NPP Krsko Spent Fuel Pool

International Nuclear Information System (INIS)

Bace, M.; Pevec, D.; Smuc, T.

1998-01-01

Using the SCALE-4 code package reracking possibilities of the NPP Krsko spent fuel pool were analyzed. Two cases were considered: the first case assuming the 40 years lifetime of the plant, and the second case assuming the 50 years lifetime of the plant. It was shown that it is possible to design the additional racks in free space of the spent fuel pool with the sufficient total capacity to store all the spent fuel generated during the 40 years lifetime of the plant. In the case of 50 years plant lifetime, completely new racks (capacity of 1890 spent fuel assemblies), containing 4mm boral in storage cell walls, were proposed for the NPP Krsko spent fuel pool. The effective multiplication factor of the spent fuel pool fully loaded with new racks containing spent fuel assemblies of initial enrichment 4.3 w/o, burned to 40 GWd/tU and cooled 2 years is lower than the value required by standard. It showed the possibility of the safe disposal of all spent fuel accumulated during more than 50 years lifetime of the plant. (author)

Spent nuclear fuel storage pool thermal-hydraulic analysis

International Nuclear Information System (INIS)

Gay, R.R.

1984-01-01

Storage methods and requirements for spent nuclear fuel at U.S. commercial light water reactors are reviewed in Section 1. Methods of increasing current at-reactor storage capabilities are also outlined. In Section 2 the development of analytical methods for the thermal-hydraulic analysis of spent fuel pools is chronicled, leading up to a discussion of the GFLOW code which is described in Section 3. In Section 4 the verification of GFLOW by comparisons of the code's predictions to experimental data taken inside the fuel storage pool at the Maine Yankee nuclear power plant is presented. The predictions of GFLOW using 72, 224, and 1584 node models of the storage pool are compared to each other and to the experimental data. An example of thermal licensing analysis for Maine Yankee using the GFLOW code is given in Section 5. The GFLOW licensing analysis is compared to previous licensing analysis performed by Yankee Atomic using the RELAP-4 computer code

13 CFR 120.1703 - Qualifications to be a Pool Originator.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Qualifications to be a Pool Originator. 120.1703 Section 120.1703 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools...

Measure Guideline. Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

Energy Technology Data Exchange (ETDEWEB)

Hunt, A. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States); Easley, S. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States)

2012-05-01

This measure guideline evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provides a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

Molten pool characterization of laser lap welded copper and aluminum

Science.gov (United States)

Xue, Zhiqing; Hu, Shengsun; Zuo, Di; Cai, Wayne; Lee, Dongkyun; Elijah, Kannatey-Asibu, Jr.

2013-12-01

A 3D finite volume simulation model for laser welding of a Cu-Al lap joint was developed using ANSYS FLUENT to predict the weld pool temperature distribution, velocity field, geometry, alloying element distribution and transition layer thickness—all key attributes and performance characteristics for a laser-welded joint. Melting and solidification of the weld pool was simulated with an enthalpy-porosity formulation. Laser welding experiments and metallographic examination by SEM and EDX were performed to investigate the weld pool features and validate the simulated results. A bowl-shaped temperature field and molten pool, and a unique maximum fusion zone width were observed near the Cu-Al interface. Both the numerical simulation and experimental results indicate an arch-shaped intermediate layer of Cu and Al, and a gradual transition of Cu concentration from the aluminum plate to the copper plate with high composition gradient. For the conditions used, welding with Cu on top was found to result in a better weld joint.

Molten pool characterization of laser lap welded copper and aluminum

International Nuclear Information System (INIS)

Xue, Zhiqing; Hu, Shengsun; Zuo, Di; Cai, Wayne; Lee, Dongkyun; Elijah, Kannatey-Asibu Jr

2013-01-01

A 3D finite volume simulation model for laser welding of a Cu–Al lap joint was developed using ANSYS FLUENT to predict the weld pool temperature distribution, velocity field, geometry, alloying element distribution and transition layer thickness—all key attributes and performance characteristics for a laser-welded joint. Melting and solidification of the weld pool was simulated with an enthalpy-porosity formulation. Laser welding experiments and metallographic examination by SEM and EDX were performed to investigate the weld pool features and validate the simulated results. A bowl-shaped temperature field and molten pool, and a unique maximum fusion zone width were observed near the Cu–Al interface. Both the numerical simulation and experimental results indicate an arch-shaped intermediate layer of Cu and Al, and a gradual transition of Cu concentration from the aluminum plate to the copper plate with high composition gradient. For the conditions used, welding with Cu on top was found to result in a better weld joint. (paper)

Extra-binomial variation approach for analysis of pooled DNA sequencing data

Science.gov (United States)

Wallace, Chris

2012-01-01

Motivation: The invention of next-generation sequencing technology has made it possible to study the rare variants that are more likely to pinpoint causal disease genes. To make such experiments financially viable, DNA samples from several subjects are often pooled before sequencing. This induces large between-pool variation which, together with other sources of experimental error, creates over-dispersed data. Statistical analysis of pooled sequencing data needs to appropriately model this additional variance to avoid inflating the false-positive rate. Results: We propose a new statistical method based on an extra-binomial model to address the over-dispersion and apply it to pooled case-control data. We demonstrate that our model provides a better fit to the data than either a standard binomial model or a traditional extra-binomial model proposed by Williams and can analyse both rare and common variants with lower or more variable pool depths compared to the other methods. Availability: Package ‘extraBinomial’ is on http://cran.r-project.org/ Contact: chris.wallace@cimr.cam.ac.uk Supplementary information: Supplementary data are available at Bioinformatics Online. PMID:22976083

Convective Cold Pool Structure and Boundary Layer Recovery in DYNAMO

Science.gov (United States)

Savarin, A.; Chen, S. S.; Kerns, B. W.; Lee, C.; Jorgensen, D. P.

2012-12-01

One of the key factors controlling convective cloud systems in the Madden-Julian Oscillation (MJO) over the tropical Indian Ocean is the property of the atmospheric boundary layer. Convective downdrafts and precipitation from the cloud systems produce cold pools in the boundary layer, which can inhibit subsequent development of convection. The recovery time is the time it takes for the boundary layer to return to pre convective conditions. It may affect the variability of the convection on various time scales during the initiation of MJO. This study examines the convective cold pool structure and boundary layer recovery using the NOAA WP-3D aircraft observations, include the flight-level, Doppler radar, and GPS dropsonde data, collected during the Dynamics of MJO (DYNAMO) field campaign from November-December 2011. The depth and strength of convective cold pools are defined by the negative buoyancy, which can be computed from the dropsonde data. Convective downdraft can be affected by environmental water vapor due to entrainment. Mid-level dry air observed during the convectively suppressed phase of MJO seems to enhance convective downdraft, making the cold pools stronger and deeper. Recovery of the cold pools in the boundary layer is determined by the strength and depth of the cold pools and also the air-sea heat and moisture fluxes. Given that the water vapor and surface winds are distinct for the convectively active and suppressed phases of MJO over the Indian Ocean, the aircraft data are stratified by the two different large-scale regimes of MJO. Preliminary results show that the strength and depth of the cold pools are inversely correlated with the surrounding mid-level moisture. During the convectively suppressed phase, the recovery time is ~5-20 hours in relative weak wind condition with small air-sea fluxes. The recovery time is generally less than 6 hours during the active phase of MJO with moist mid-levels and stronger surface wind and air-sea fluxes.

A swimming pool array for ultra high energy showers

Science.gov (United States)

Yodh, Gaurang B.; Shoup, Anthony; Barwick, Steve; Goodman, Jordan A.

1992-11-01

A very preliminary design concept for an array using water Cherenkov counters, built out of commercially available backyard swimming pools, to sample the electromagnetic and muonic components of ultra high energy showers at large lateral distances is presented. The expected performance of the pools is estimated using the observed lateral distributions by scintillator and water Cherenkov arrays at energies above 1019 eV and simulations.

Impact and quantification of the sources of error in DNA pooling designs.

Science.gov (United States)

Jawaid, A; Sham, P

2009-01-01

The analysis of genome wide variation offers the possibility of unravelling the genes involved in the pathogenesis of disease. Genome wide association studies are also particularly useful for identifying and validating targets for therapeutic intervention as well as for detecting markers for drug efficacy and side effects. The cost of such large-scale genetic association studies may be reduced substantially by the analysis of pooled DNA from multiple individuals. However, experimental errors inherent in pooling studies lead to a potential increase in the false positive rate and a loss in power compared to individual genotyping. Here we quantify various sources of experimental error using empirical data from typical pooling experiments and corresponding individual genotyping counts using two statistical methods. We provide analytical formulas for calculating these different errors in the absence of complete information, such as replicate pool formation, and for adjusting for the errors in the statistical analysis. We demonstrate that DNA pooling has the potential of estimating allele frequencies accurately, and adjusting the pooled allele frequency estimates for differential allelic amplification considerably improves accuracy. Estimates of the components of error show that differential allelic amplification is the most important contributor to the error variance in absolute allele frequency estimation, followed by allele frequency measurement and pool formation errors. Our results emphasise the importance of minimising experimental errors and obtaining correct error estimates in genetic association studies.

A general framework for the regression analysis of pooled biomarker assessments.

Science.gov (United States)

Liu, Yan; McMahan, Christopher; Gallagher, Colin

2017-07-10

As a cost-efficient data collection mechanism, the process of assaying pooled biospecimens is becoming increasingly common in epidemiological research; for example, pooling has been proposed for the purpose of evaluating the diagnostic efficacy of biological markers (biomarkers). To this end, several authors have proposed techniques that allow for the analysis of continuous pooled biomarker assessments. Regretfully, most of these techniques proceed under restrictive assumptions, are unable to account for the effects of measurement error, and fail to control for confounding variables. These limitations are understandably attributable to the complex structure that is inherent to measurements taken on pooled specimens. Consequently, in order to provide practitioners with the tools necessary to accurately and efficiently analyze pooled biomarker assessments, herein, a general Monte Carlo maximum likelihood-based procedure is presented. The proposed approach allows for the regression analysis of pooled data under practically all parametric models and can be used to directly account for the effects of measurement error. Through simulation, it is shown that the proposed approach can accurately and efficiently estimate all unknown parameters and is more computational efficient than existing techniques. This new methodology is further illustrated using monocyte chemotactic protein-1 data collected by the Collaborative Perinatal Project in an effort to assess the relationship between this chemokine and the risk of miscarriage. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Spent fuel and fuel pool component integrity. Annual report, FY 1979

International Nuclear Information System (INIS)

Johnson, A.B. Jr.; Bailey, W.J.; Schreiber, R.E.; Kustas, F.M.

1980-05-01

International meetings under the BEFAST program and under INFCE Working Group No. 6 during 1978 and 1979 continue to indicate that no cases of fuel cladding degradation have developed on pool-stored fuel from water reactors. A section from a spent fuel rack stand, exposed for 1.5 y in the Yankee Rowe (PWR) pool had 0.001- to 0.003-in.-deep (25- to 75-μm) intergranular corrosion in weld heat-affected zones but no evidence of stress corrosion cracking. A section of a 304 stainless steel spent fuel storage rack exposed 6.67 y in the Point Beach reactor (PWR) spent fuel pool showed no significant corrosion. A section of 304 stainless steel 8-in.-dia pipe from the Three Mile Island No. 1 (PWR) spent fuel pool heat exchanger plumbing developed a through-wall crack. The crack was intergranular, initiating from the inside surface in a weld heat-affected zone. The zone where the crack occurred was severely sensitized during field welding. The Kraftwerk Union (Erlangen, GFR) disassembled a stainless-steel fuel-handling machine that operated for 12 y in a PWR (boric acid) spent fuel pool. There was no evidence of deterioration, and the fuel-handling machine was reassembled for further use. A spent fuel pool at a Swedish PWR was decontaminated. The procedure is outlined in this report

Research program on the feasibility of pool type LMFBR in Japan

International Nuclear Information System (INIS)

Hattori, Sadao

1982-01-01

The Central Research Institute of Electric Power Industry has started the feasibility study to evaluate the possiblity of existence of large pool type FBR plants in Japan as the three-year project from fiscal 1981. The development of FBRs is indispensable for the effective use of nuclear fuel and the establishment of energy security. The knowledge on the characteristics of FBR core, sodium technology and others has advanced rapidly in Japan. At the stage of the practical reactors with large capacity, the pool type is naturally considered as the object of selection, but the aseismatic capability and safety of the large containment vessels for the pool type and the qualitative and quantitative acceptability of the research and development for the pool type are the problems. The difference between the loop type and the pool type is only the structural change arising from the difference in the arrangement of equipment. The pool type reactors have been operated already in the UK and France. The objective of the research and main subjects, the total plan and research organization, the fundamental condition of investigation, the research procedure for respective subjects, and the outline of model test are discribed. The change of design and safety standards in the future must be predicted and taken in consideration in the research. (Kako, I.)

Cryptosporidium and Giardia in Swimming Pools, Atlanta, Georgia

Centers for Disease Control (CDC) Podcasts

2008-05-29

In this podcast, Dan Rutz speaks with Dr. Joan Shields, a guest researcher with the Healthy Swimming Program at CDC, about an article in June 2008 issue of Emerging Infectious Diseases reporting on the results of a test of swimming pools in the greater Atlanta, Georgia area. Dr. Shields tested 160 pools in metro Atlanta last year for Cryptosporidium and Giardia. These germs cause most recreational water associated outbreaks.  Created: 5/29/2008 by Emerging Infectious Diseases.   Date Released: 5/29/2008.

Analytical real-time measurement of a three-dimensional weld pool surface

International Nuclear Information System (INIS)

Zhang, WeiJie; Zhang, YuMing; Wang, XueWu

2013-01-01

The ability to observe and measure weld pool surfaces in real-time is the core of the foundation for next generation intelligent welding that can partially imitate skilled welders who observe the weld pool to acquire information on the welding process. This study aims at the real-time measurement of the specular three-dimensional (3D) weld pool surface under a strong arc in gas tungsten arc welding (GTAW). An innovative vision system is utilized in this study to project a dot-matrix laser pattern on the specular weld pool surface. Its reflection from the surface is intercepted at a distance from the arc by a diffuse plane. The intercepted laser dots illuminate this plane producing an image showing the reflection pattern. The deformation of this reflection pattern from the projected pattern (e.g. the dot matrix) is used to derive the 3D shape of the reflection surface, i.e., the weld pool surface. Based on careful analysis, the underlying reconstruction problem is formulated mathematically. An analytic solution is proposed to solve this formulated problem resulting in the weld pool surface being reconstructed on average in 3.04 ms during welding experiments. A vision-based monitoring system is thus established to measure the weld pool surface in GTAW in real-time. In order to verify the effectiveness of the proposed reconstruction algorithm, first numerical simulation is conducted. The proposed algorithm is then tested on a spherical convex mirror with a priori knowledge of its geometry. The detailed analysis of the measurement error validates the accuracy of the proposed algorithm. Results from the real-time experiments verify the robustness of the proposed reconstruction algorithm. (paper)

76 FR 72923 - Pool Corporation; Analysis To Aid Public Comment

Science.gov (United States)

2011-11-28

... manufacturers, warehouse them, and then resell the products to pool retail stores, pool service companies and.... ADDRESSES: Interested parties may file a comment online or on paper, by following the instructions in the... 0115'' on your comment, and file your comment online at https://ftcpublic.commentworks.com/ftc...

7 CFR 1007.7 - Pool plant.

Science.gov (United States)

2010-01-01

...-upon use other than Class I shall be excluded from the supply plant's shipments in computing the plant... under the order in this part, or such plant has automatic pooling status under such other order. (h) Any...

Analysis of implementing phase change materials in open-air swimming pools

OpenAIRE

Zsembinszki, Gabriel; Farid, Mohammed M.; Cabeza, Luisa F.

2012-01-01

Open-air swimming pools in Mediterranean climate regions are heated by direct solar radiation with no auxiliary heating systems. In order to extend the swimming season or improve comfort conditions, solar collectors or pool coverings may be used. In this paper, another approach was followed through the use of phase change materials (PCM). Two methods of introducing the PCM were considered: (1) encapsulated in the sidewalls and bottom of the pool, and (2) use the PCM in an external he...

Characteristics of pools used by adult summer steelhead oversummering in the New River, California

Science.gov (United States)

Rodney J. Nakamoto

1994-01-01

Abstract - I assessed characteristics of pools used by oversummering adults of summer steelhead Oncorhynchus mykiss between July and October 1991 in the New River, northwestern California. Most fish occupied channel confluence pools and other pools of moderate size (200-1,200 m 2); these pools had less than 35% substrate embeddedness and mean water depths of about 1.0...

CERN Electronics Pool presentations

CERN Multimedia

2011-01-01

The CERN Electronics Pool has organised a series of presentations in collaboration with oscilloscope manufacturers. The last one will take place according to the schedule below.   Time will be available at the end of the presentation to discuss your personal needs. The Agilent presentation had to be postponed and will be organised later. -     Lecroy: Thursday, 24 November 2011, in 530-R-030, 14:00 to 16:30.

Induced venous pooling and cardiorespiratory responses to exercise after bed rest

Science.gov (United States)

Convertino, V. A.; Sandler, H.; Webb, P.; Annis, J. F.

1982-01-01

Venous pooling induced by a specially constructed garment is investigated as a possible means for reversing the reduction in maximal oxygen uptake regularly observed following bed rest. Experiments involved a 15-day period of bed rest during which four healthy male subjects, while remaining recumbent in bed, received daily 210-min venous pooling treatments from a reverse gradient garment supplying counterpressure to the torso. Results of exercise testing indicate that while maximal oxygen uptake endurance time and plasma volume were reduced and maximal heart rate increased after bed rest in the control group, those parameters remained essentially unchanged for the group undergoing venous pooling treatment. Results demonstrate the importance of fluid shifts and venous pooling within the cardiovascular system in addition to physical activity to the maintenance of cardiovascular conditioning.

Trophic interactions among the heterotrophic components of plankton in man-made peat pools

Directory of Open Access Journals (Sweden)

Michał Niedźwiecki

2017-03-01

Full Text Available Man-made peat pools are permanent freshwater habitats developed due to non-commercial man-made peat extraction. Yet, they have not been widely surveyed in terms of ecosystem functioning, mainly regarding the complexity of heterotrophic components of the plankton. In this study we analysed distribution and trophic interrelations among heterotrophic plankton in man-made peat pools located in different types of peatbogs. We found that peat pools showed extreme differences in environmental conditions that occurred to be important drivers of distribution of microplankton and metazooplankton. Abundance of bacteria and protozoa showed significant differences, whereas metazooplankton was less differentiated in density among peat pools. In all peat pools stress-tolerant species of protozoa and metazoa were dominant. In each peat pool five trophic functional groups were distinguished. The abundance of lower functional trophic groups (bacteria, heterotrophic nanoflagellates (HNF and ciliates feeding on bacteria and HNF was weakly influenced by environmental drivers and was highly stable in all peat pool types. Higher functional trophic groups (naupli, omnivorous and carnivorous ciliates, cladocerans, adult copepods and copepodites were strongly influenced by environmental variables and exhibited lower stability. Our study contributes to comprehensive knowledge of the functioning of peat bogs, as our results have shown that peat pools are characterized by high stability of the lowest trophic levels, which can be crucial for energy transfer and carbon flux through food webs.

Modeling of the Temperature Field Recovery in the Oil Pool

Science.gov (United States)

Khabibullin, I. L.; Davtetbaev, A. Ya.; Mar'in, D. F.; Khisamov, A. A.

2018-05-01

This paper considers the problem on mathematical modeling of the temperature field recovery in the oil pool upon termination of injection of water into the pool. The problem is broken down into two stages: injection of water and temperature and pressure recovery upon termination of injection. A review of the existing mathematical models is presented, analytical solutions for a number of cases have been constructed, and a comparison of the analytical solutions of different models has been made. In the general form, the expression has been obtained that permits determining the temperature change in the oil pool upon termination of injection of water (recovery of the temperature field).

Clinical blood pool MR Imaging

Energy Technology Data Exchange (ETDEWEB)

Leiner, Tim [Maastrich University Medical Center (Netherlands). Dept. of Radiology; Goyen, Martin [University Medical Center Hamburg-Eppendorf (Germany); Rohrer, Mathias [Bayer Schering Pharma AG, Berlin (Germany). European Business Unit Diagnostic Imaging; Schoenberg, Stefan O. (eds.) [University Hospital Mannheim Medical Faculty Mannheim - Heidelberg Univ. (Germany). Dept. of Clinical Radiology and Nuclear Medicine

2008-07-01

Clinical Blood Pool MR Imaging - This excellent treatise on Vasovist {sup registered} created by a team of exceptional faculty who are pioneers in MR Angiography covers the basic techniques, safety, efficacy, image processing and pharmaco-economic details to successfully implement a new level of MRA image quality with this new contrast agent. Martin Prince, Cornell University, New York The editors and authors have made groundbreaking contributions towards establishing MR angiography in various investigative settings, rendering it more precise and applying it for diverse indications. The work presented here is founded upon the extensive experience of the editors, as well as the broad range of experience from other scientific working groups. Maximilian Reiser, Ludwig Maximilian University, Munich Vasovist {sup registered} (Gadofosveset), worldwide the first blood pool agent, has only recently become available for clinical use, but has already gained wide acceptance as a tool to improve magnetic resonance angiography. This book presents the first in-depth introduction to the basic physicochemical aspects of the agent, the application of Vasovist {sup registered} in clinical MRA, as well as potential clinical applications beyond MRA and patient management-related aspects. The first part of the book explains basic and technical properties of the agent and the differences of Vasovist {sup registered} compared to currently available extracellular agents. The second part contains detailed chapters on safety and efficacy. In the third part the focus is on MR angiographic applications, and in the fourth part of the book potential clinical fields beyond MRA are explored. All clinical chapters feature ready-to-use clinical protocols and a series of take home messages that concisely summarize the current role of blood pool imaging for each specific indication. (orig.)

Convective cooling in a pool-type research reactor

Energy Technology Data Exchange (ETDEWEB)

Sipaun, Susan, E-mail: susan@nm.gov.my [Malaysian Nuclear Agency, Industrial Technology Division, Blok 29T, Bangi 43200, Selangor (Malaysia); Usman, Shoaib, E-mail: usmans@mst.edu [Missouri University of Science and Technology, Nuclear Engineering, 222 Fulton Hall 301 W.14th St., Rolla 64509 MO (United States)

2016-01-22

A reactor produces heat arising from fission reactions in the nuclear core. In the Missouri University of Science and Technology research reactor (MSTR), this heat is removed by natural convection where the coolant/moderator is demineralised water. Heat energy is transferred from the core into the coolant, and the heated water eventually evaporates from the open pool surface. A secondary cooling system was installed to actively remove excess heat arising from prolonged reactor operations. The nuclear core consists of uranium silicide aluminium dispersion fuel (U{sub 3}Si{sub 2}Al) in the form of rectangular plates. Gaps between the plates allow coolant to pass through and carry away heat. A study was carried out to map out heat flow as well as to predict the system’s performance via STAR-CCM+ simulation. The core was approximated as porous media with porosity of 0.7027. The reactor is rated 200kW and total heat density is approximately 1.07+E7 Wm{sup −3}. An MSTR model consisting of 20% of MSTR’s nuclear core in a third of the reactor pool was developed. At 35% pump capacity, the simulation results for the MSTR model showed that water is drawn out of the pool at a rate 1.28 kg s{sup −1} from the 4” pipe, and predicted pool surface temperature not exceeding 30°C.

13 CFR 120.620 - SBA guarantee of a Pool Certificate.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false SBA guarantee of a Pool Certificate. 120.620 Section 120.620 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Secondary Market The Sba Guarantee of A Certificate § 120.620 SBA guarantee of a Pool Certificate...

13 CFR 120.1726 - Pool Certificates a Seller cannot purchase.

Science.gov (United States)

2010-01-01

... that the Seller, or any of its Program Associates or Affiliates, originated or owned, and, in the event... LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1726 Pool Certificates a Seller cannot purchase. Neither a Seller, nor any of its Program...

Safety classification of systems, structures, and components for pool-type research reactors

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae Ryong [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2016-08-15

Structures, systems, and components (SSCs) important to safety of nuclear facilities shall be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety functions. Although SSC classification guidelines for nuclear power plants have been well established and applied, those for research reactors have been only recently established by the International Atomic Energy Agency (IAEA). Korea has operated a pool-type research reactor (the High Flux Advanced Neutron Application Reactor) and has recently exported another pool-type reactor (Jordan Research and Training Reactor), which is being built in Jordan. Korea also has a plan to build one more pool-type reactor, the Kijang Research Reactor, in Kijang, Busan. The safety classification of SSCs for pool-type research reactors is proposed in this paper based on the IAEA methodology. The proposal recommends that the SSCs of pool-type research reactors be categorized and classified on basis of their safety functions and safety significance. Because the SSCs in pool-type research reactors are not the pressure-retaining components, codes and standards for design of the SSCs following the safety classification can be selected in a graded approach.

Estimation of reactor pool water temperature after shutdown in JRR-3M

International Nuclear Information System (INIS)

Yagi, Masahiro; Sato, Mitsugu; Kakefuda, Kazuhiro

1999-01-01

The reactor pool water temperature increasing by the decay heat was estimated by calculation. The reactor pool water temperature was calculated by increased enthalpy that was estimated by the reactor decay heat, the heat released from the reactor biological shielding concrete, reactor pool water surface, the heat conduction from the canal and the core inlet piping. These results of calculation were compared with the past measured data. As the results of estimation, after the JRR-3M shutdown, the calculated reactor pool temperature first increased sharply. This is because the decay heat was the major contribution. And then, rate of increased reactor pool temperature decreased. This is because the ratio of heat released from reactor biological shielding concrete and core inlet piping to the decay heat increased. Besides, the calculated reactor pool water temperature agreed with the past measured data in consequence of correcting the decay heat and the released heat. The corrected coefficient k 1 of decay heat was 0.74 - 0.80. And the corrected coefficient k 2 of heat released from the reactor biological shielding concrete was 3.5 - 4.5. (author)

Boosting Active Contours for Weld Pool Visual Tracking in Automatic Arc Welding

DEFF Research Database (Denmark)

Liu, Jinchao; Fan, Zhun; Olsen, Søren Ingvor

2015-01-01

Detecting the shape of the non-rigid molten metal during welding, so-called weld pool visual sensing, is one of the central tasks for automating arc welding processes. It is challenging due to the strong interference of the high-intensity arc light and spatters as well as the lack of robust...... approaches to detect and represent the shape of the nonrigid weld pool. We propose a solution using active contours including an prior for the weld pool boundary composition. Also, we apply Adaboost to select a small set of features that captures the relevant information. The proposed method is applied...... to weld pool tracking and the presented results verified its feasibility....

Immobilization of radioactive waste sludge from spent fuel storage pool

International Nuclear Information System (INIS)

Pavlovic, R.; Plecas, I.

1998-01-01

In the last forty years, in FR Yugoslavia, as result of the research reactors' operation and radionuclides application in medicine, industry and agriculture, radioactive waste materials of the different categories and various levels of specific activities were generated. As a temporary solution, these radioactive waste materials are stored in the two hanger type interim storages for solid waste and some type of liquid waste packed in plastic barrels, and one of three stainless steal underground containers for other types of liquid waste. Spent fuel elements from nuclear reactors in the Vinca Institute have been temporary stored in water filled storage pool. Due to the fact that the water in the spent fuel elements storage pool have not been purified for a long time, all metallic components submerged in the water have been hardly corroded and significant amount of the sludge has been settled on the bottom of the pool. As a first step in improving spent fuel elements storage conditions and slowing down corrosion in the storage spent fuel elements pool we have decided to remove the sludge from the bottom of the pool. Although not high, but slightly radioactive, this sludge had to be treated as radioactive waste material. Some aspects of immobilisation, conditioning and storage of this sludge are presented in this paper. (author

An accurate clone-based haplotyping method by overlapping pool sequencing.

Science.gov (United States)

Li, Cheng; Cao, Changchang; Tu, Jing; Sun, Xiao

2016-07-08

Chromosome-long haplotyping of human genomes is important to identify genetic variants with differing gene expression, in human evolution studies, clinical diagnosis, and other biological and medical fields. Although several methods have realized haplotyping based on sequencing technologies or population statistics, accuracy and cost are factors that prohibit their wide use. Borrowing ideas from group testing theories, we proposed a clone-based haplotyping method by overlapping pool sequencing. The clones from a single individual were pooled combinatorially and then sequenced. According to the distinct pooling pattern for each clone in the overlapping pool sequencing, alleles for the recovered variants could be assigned to their original clones precisely. Subsequently, the clone sequences could be reconstructed by linking these alleles accordingly and assembling them into haplotypes with high accuracy. To verify the utility of our method, we constructed 130 110 clones in silico for the individual NA12878 and simulated the pooling and sequencing process. Ultimately, 99.9% of variants on chromosome 1 that were covered by clones from both parental chromosomes were recovered correctly, and 112 haplotype contigs were assembled with an N50 length of 3.4 Mb and no switch errors. A comparison with current clone-based haplotyping methods indicated our method was more accurate. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Analysis of natural convection in volumetrically-heated melt pools

International Nuclear Information System (INIS)

Sehgal, B.R.; Dinh, T.N.; Nourgaliev, R.R.

1996-12-01

Results of series of studies on natural convection heat transfer in decay-heated core melt pools which form in a reactor lower plenum during the progression of a core meltdown accident are described. The emphasis is on modelling and prediction of turbulent heat transfer characteristics of natural convection in a liquid pool with an internal energy source. Methods of computational fluid dynamics, including direct numerical simulation, were applied for investigation

Seasonal Change in Nearshore and Channel Morphology at Packery Channel, A New Inlet Serving Corpus Christi, Texas

Science.gov (United States)

2011-01-01

position defined by limiting features such as the dune toe or seawall. Individual transects are spaced at 1 to 30 m apart. These surveys usually require...associated nominal depths (MSL) are: 1) a wading survey conducted from the landward limiting feature, such as dune or seawall, to offshore depth of...Hall Pier. The surge forced water up to the dune line adjacent to the channel. The water was funneled toward and into the inlet, introducing sand from

Probing the O-glycoproteome of Gastric Cancer Cell Lines for Biomarker Discovery

DEFF Research Database (Denmark)

Vieira Campos, Diana Alexandra; Freitas, Daniela; Gomes, Joana

2015-01-01

biomarker assays. However, the current knowledge of secreted and circulating O-glycoproteins is limited. Here, we used the COSMC KO "SimpleCell" (SC) strategy to characterize the O-glycoproteome of two gastric cancer SC lines (AGS, MKN45) as well as a gastric cell line (KATO III) which naturally expresses...... at least partially truncated O-glycans. Overall we identified 499 O-glycoproteins and 1,236 O-glycosites in gastric cancer SCs, and a total 47 O-glycoproteins and 73 O-glycosites in the KATO III cell line. We next modified the glycoproteomic strategy to apply it to pools of sera from gastric cancer...... with the STn glycoform were further validated as being expressed in gastric cancer tissue. A proximity ligation assay was used to demonstrate that CD44 was expressed with the STn glycoform in gastric cancer tissues. The study provides a discovery strategy for aberrantly glycosylated O-glycoproteins and a set...

Sodium-water reaction in double pool LMFBR, (5)

International Nuclear Information System (INIS)

Yoshida, Kazuo; Kumagai, Hiromichi; Nishi, Yoshihisa; Uotani, Masaki

1990-01-01

Experiments were conducted using a 1/5 scale model of the Double Pool in order to evaluate a pressure rise caused by a large scale sodium-water reaction. The experiments were focused on the pressure rise caused by the piston motion of liquid sodium. It appeared from the results that the magnitude of this pressure rise depends on the depth of reaction point, and that a pressure rise more than 1 MPa would arise in the real Double Pool plant. A new design of steam generator is proposed to mitigate the pressure rise. (author)

Chemical Safety Alert: Safe Storage and Handling of Swimming Pool Chemicals

Science.gov (United States)

Hazards of pool water treatment and maintenance chemicals (e.g., chlorine), and the protective measures pool owners should take to prevent fires, toxic vapor releases, and injuries. Triggered by improper wetting, mixing, or self-reactivity over time.

Laboratory studies on the effect of ozonation on THM formation in swimming pool water

DEFF Research Database (Denmark)

Hansen, Kamilla Marie Speht; Spiliotopoulou, Aikaterini; Cheema, Waqas Akram

2015-01-01

Water samples from indoor swimming pool were ozonated at different pH values to evaluate the effect of pH on decomposition of ozone in swimming pool water. Furthermore, drinking and pool water were repeatedly ozonated followed by chlorination to evaluate THM formation. Decomposition of ozone...... was not affected by pH in the range relevant to swimming pools (pH 6.8 – 7.8) and a half-life time at 10-12 min was obtained. Repeating the ozonation, the decomposition of ozone increased at the second dose of ozone added (t½,2=8 min) and then decreased again at the third and fourth dose of ozone (t½,3=17 min; t...... chlorine for drinking water as lower TTHM formation occurred than in non-ozonated samples. For pool water, a higher TTHM formation was observed in ozonated than non-ozonated pool water. Thus, it was observed that ozone reacts markedly different in swimming pool water from the known pattern in drinking...

Investigation of pool thermal hydraulics and temperature distribution in inner vessel under mechanical seal leakage

International Nuclear Information System (INIS)

Abraham, Juby; Velusamy, K.; Selvaraj, P.

2015-01-01

The primary heat sink of prototype fast breeder reactor is a sodium pool which is partitioned into cold pool and hot pool. The inner vessel which separates the cold and hot pools is having penetrations for intermediate heat exchangers. The hot sodium from hot pool leaks into the cold pool through these penetrations and to reduce the leakage, mechanical seals are provided. Leakage of hot sodium into cold pool can lead to thermal stratification in the cold pool and also will affect the temperature distribution in inner vessel. 3-D CFD studies were performed focusing these features as a function of sodium leakage. The analyses indicate that the maximum temperature difference across the IV thickness is 65°C without any leakage of sodium. The temperature difference is found to decrease with increase in leakage through the seals. It is seen that a leakage of 2.5% is acceptable. (author)

Sodium pool fire model for CONACS code

International Nuclear Information System (INIS)

Yung, S.C.

1982-01-01

The modeling of sodium pool fires constitutes an important ingredient in conducting LMFBR accident analysis. Such modeling capability has recently come under scrutiny at Westinghouse Hanford Company (WHC) within the context of developing CONACS, the Containment Analysis Code System. One of the efforts in the CONACS program is to model various combustion processes anticipated to occur during postulated accident paths. This effort includes the selection or modification of an existing model and development of a new model if it clearly contributes to the program purpose. As part of this effort, a new sodium pool fire model has been developed that is directed at removing some of the deficiencies in the existing models, such as SOFIRE-II and FEUNA

Pricing Electricity in Pools With Wind Producers

DEFF Research Database (Denmark)

Morales González, Juan Miguel; Conejo, A. J.; Kai Liu

2012-01-01

This paper considers an electricity pool that includes a significant number of wind producers and is cleared through a network-constrained auction, one day in advance and on an hourly basis. The hourly auction is formulated as a two-stage stochastic programming problem, where the first stage...... represents the clearing of the market and the second stage models the system operation under a number of plausible wind production realizations. This formulation co-optimizes energy and reserve, and allows deriving both pool energy prices and balancing energy prices. These prices result in both cost recovery...... for producers and revenue reconciliation. A case study of realistic size is used to illustrate the functioning of the proposed pricing scheme....

Slower lower limb blood pooling in young women with orthostatic intolerance.

Science.gov (United States)

Lindenberger, Marcus; Länne, Toste

2015-01-01

What is the central question of this study? Orthostatic stress is mostly caused by venous blood pooling in the lower limbs. Venous distension elicits sympathetic responses, and increased distension speed enhances the cardiovascular response. We examine whether lower limb blood pooling rate during lower body negative pressure is linked to orthostatic intolerance. What is the main finding and its importance? A similar amount of blood was pooled in the lower limb, but at a slower rate in women who developed signs of orthostatic intolerance. The difference in blood pooling rate increased with orthostatic stress and was most prominent at a presyncope-inducing level of lower body negative pressure. The findings have implications for the pathophysiology as well as treatment of orthostatic intolerance. Vasovagal syncope is common in young women, but its aetiology remains elusive. Orthostatic stress-induced lower limb blood pooling is linked with central hypovolaemia and baroreceptor unloading. Venous distension in the arm elicits a sympathetic response, which is enhanced with more rapid distension. Our aim was to study both the amount and the speed of lower limb pooling during orthostatic stress and its effects on compensatory mechanisms to maintain cardiovascular homeostasis in women with orthostatic intolerance. Twenty-seven healthy women, aged 20-27 years, were subjected to a lower body negative pressure (LBNP) of 11-44 mmHg. Five women developed symptoms of vasovagal syncope (orthostatic intolerant) and were compared with the remaining women, who tolerated LBNP well (orthostatic tolerant). Lower limb blood pooling, blood flow and compensatory mobilization of venous capacitance blood were measured. Lower body negative pressure induced equal lower limb blood pooling in both groups, but at a slower rate in orthostatic intolerant women (e.g. time to 50% of total blood pooling, orthostatic intolerant 44 ± 7 s and orthostatic tolerant 26 ± 2 s; P intolerant women (P = 0

Spectrum pooling in MnWave Networks

DEFF Research Database (Denmark)

Boccardi, Federico; Shokri-Ghadikolaei, Hossein; Fodor, Gabor

2016-01-01

Motivated by the specific characteristics of mmWave technologies, we discuss the possibility of an authorization regime that allows spectrum sharing between multiple operators, also referred to as spectrum pooling. In particular, considering user rate as the performance measure, we assess...

Influence of the arc plasma parameters on the weld pool profile in TIG welding

Science.gov (United States)

Toropchin, A.; Frolov, V.; Pipa, A. V.; Kozakov, R.; Uhrlandt, D.

2014-11-01

Magneto-hydrodynamic simulations of the arc and fluid simulations of the weld pool can be beneficial in the analysis and further development of arc welding processes and welding machines. However, the appropriate coupling of arc and weld pool simulations needs further improvement. The tungsten inert gas (TIG) welding process is investigated by simulations including the weld pool. Experiments with optical diagnostics are used for the validation. A coupled computational model of the arc and the weld pool is developed using the software ANSYS CFX. The weld pool model considers the forces acting on the motion of the melt inside and on the surface of the pool, such as Marangoni, drag, electromagnetic forces and buoyancy. The experimental work includes analysis of cross-sections of the workpieces, highspeed video images and spectroscopic measurements. Experiments and calculations have been performed for various currents, distances between electrode and workpiece and nozzle diameters. The studies show the significant impact of material properties like surface tension dependence on temperature as well as of the arc structure on the weld pool behaviour and finally the weld seam depth. The experimental weld pool profiles and plasma temperatures are in good agreement with computational results.

Influence of the arc plasma parameters on the weld pool profile in TIG welding

International Nuclear Information System (INIS)

Toropchin, A; Frolov, V; Pipa, A V; Kozakov, R; Uhrlandt, D

2014-01-01

Magneto-hydrodynamic simulations of the arc and fluid simulations of the weld pool can be beneficial in the analysis and further development of arc welding processes and welding machines. However, the appropriate coupling of arc and weld pool simulations needs further improvement. The tungsten inert gas (TIG) welding process is investigated by simulations including the weld pool. Experiments with optical diagnostics are used for the validation. A coupled computational model of the arc and the weld pool is developed using the software ANSYS CFX. The weld pool model considers the forces acting on the motion of the melt inside and on the surface of the pool, such as Marangoni, drag, electromagnetic forces and buoyancy. The experimental work includes analysis of cross-sections of the workpieces, highspeed video images and spectroscopic measurements. Experiments and calculations have been performed for various currents, distances between electrode and workpiece and nozzle diameters. The studies show the significant impact of material properties like surface tension dependence on temperature as well as of the arc structure on the weld pool behaviour and finally the weld seam depth. The experimental weld pool profiles and plasma temperatures are in good agreement with computational results

EP BICYCLE POOL - VIGNETTES 2002

CERN Multimedia

EP-SMI Help Desk

2002-01-01

The vignettes (insurance certificates) for 2002 become obligatory from 1 June. If you have a bicycle from the EP Pool, please bring it to the EP-SMI Help Desk (Building 124) on any working day up to 31 May between 8h.30 - 12h.00 or 13h.30 - 17h.30. EP-SMI Help Desk

Pooling, meta-analysis, and the evaluation of drug safety

Directory of Open Access Journals (Sweden)

Leizorovicz Alain

2002-03-01

Full Text Available Abstract Background The "integrated safety report" of the drug registration files submitted to health authorities usually summarizes the rates of adverse events observed for a new drug, placebo or active control drugs by pooling the safety data across the trials. Pooling consists of adding the numbers of events observed in a given treatment group across the trials and dividing the results by the total number of patients included in this group. Because it considers treatment groups rather than studies, pooling ignores validity of the comparisons and is subject to a particular kind of bias, termed "Simpson's paradox." In contrast, meta-analysis and other stratified analyses are less susceptible to bias. Methods We use a hypothetical, but not atypical, application to demonstrate that the results of a meta-analysis can differ greatly from those obtained by pooling the same data. In our hypothetical model, a new drug is compared to 1 a placebo in 4 relatively small trials in patients at high risk for a certain adverse event and 2 an active reference drug in 2 larger trials of patients at low risk for this event. Results Using meta-analysis, the relative risk of experiencing the adverse event with the new drug was 1.78 (95% confidence interval [1.02; 3.12] compared to placebo and 2.20 [0.76; 6.32] compared to active control. By pooling the data, the results were, respectively, 1.00 [0.59; 1.70] and 5.20 [2.07; 13.08]. Conclusions Because these findings could mislead health authorities and doctors, regulatory agencies should require meta-analyses or stratified analyses of safety data in drug registration files.

Cell kinetics of irradiated experimental tumors: cell transition from the non-proliferating to the proliferating pool

International Nuclear Information System (INIS)

Potmesil, M.; Goldfeder, A.

1980-01-01

In murine mammary carcinomas, parenchymal tumor cells with dense nucleoli traverse the cell cycle and divide, thus constituting the proliferating pool. Cells with trabeculate or ring-shaped nucleoli either proceed slowly through G 1 phase or are arrested in it. The role of these non-proliferating, G 1 phase-confined cells in tumor regeneration was studied in vivo after a subcurative dose of X-irradiation in two transplantable tumor lines. Tumor-bearing mice were continuously injected with methyl[ 3 H]thymidine before and after irradiation. Finally, the labeling was discontinued, mice injected with vincristine sulfate and cells arrested in metaphase were accumulated over 10-hrs. Two clearly delineated groups of vincristine-arrested mitoses emerged in autoradiograms prepared from tumor tissue at the time of starting tumor regrowth: one group with the silver-grain counts corresponding to the background level, the other with heavily labeled mitoses. As the only source of unlabeled mitoses was unlabeled G 1 phase-confined cells persisting in the tumor, this indicated cell transition from the non-proliferating to the proliferating pool, which took place in the initial phase of the tumor regrowth. Unlabeled progenitors have apparently remained in G 1 phase for at least 5-12 days after irradiation. (author)

Odonata (Insecta at a wadi Pool near Nizwa, northern Oman

Directory of Open Access Journals (Sweden)

Elaine M. Cowan

2015-07-01

Full Text Available Fourteen damselfly and dragonfly species were recorded in 68 visits to a wadi pool in northern Oman, March 2012 to June 2014.  All identifications were based on photographs.  Apparently the pool has a core community of eight resident species.  Paragomphus sinaiticus, globally Near Threatened, was regularly  recorded. 

Statistical evaluation of steam condensation loads in pressure suppression pool, (1)

International Nuclear Information System (INIS)

Kukita, Yutaka; Takeshita, Isao; Namatame, Ken; Shiba, Masayoshi; Kato, Masami; Moriya, Kumiaki.

1981-10-01

The LOCA steam condensation loads in the BWR pressure suppression pool was evaluated with use of the test data obtained in the first eight tests of the JAERI Full-Scale Mark II CRT Program. Through this evaluation, finite desynchronization between the vent pressures during the chugging and the condensation oscillation phases was identified and quantified. The characteristics of the pressure oscillation propagation through the vent pipe and in the pool water, the fluid-structure-interaction (FSI) effects on the pool pressure loads, and the characteristics of the vent lateral loads were also investigated. (author)

Swimming pool attendance and respiratory symptoms and allergies among Dutch children

NARCIS (Netherlands)

Jacobs, J.H.; Fuertes, E.; Krop, E.J.M.; Spithoven, J.; Tromp, P.; Heederik, D.J.J.

2012-01-01

OBJECTIVES To describe associations among swimming, respiratory health, allergen sensitisation and Clara cell protein 16 (CC16) levels in Dutch schoolchildren. Trichloramine levels in swimming pool air were determined to assess potential exposure levels. METHODS Respiratory health and pool

Modeling of condensation, stratification, and mixing phenomena in a pool of water

Energy Technology Data Exchange (ETDEWEB)

Li, H.; Kudinov, P.; Villanueva, W. (Royal Institute of Technology (KTH). Div. of Nuclear Power Safety, Stockholm (Sweden))

2010-12-15

This work pertains to the research program on Containment Thermal-Hydraulics at KTH. The objective is to evaluate and improve performance of methods, which are used to analyze thermal-hydraulics of steam suppression pools in a BWR plant under different abnormal transient and accident conditions. As a passive safety system, the function of steam pressure suppression pools is paramount to the containment performance. In the present work, the focus is on apparently-benign but intricate and potentially risk-significant scenarios in which thermal stratification could significantly impede the pool's pressure suppression capacity. For the case of small flow rates of steam influx, the steam condenses rapidly in the pool and the hot condensate rises in a narrow plume above the steam injection plane and spreads into a thin layer at the pool's free surface. When the steam flow rate increases significantly, momentum introduced by the steam injection and/or periodic expansion and shrink of large steam bubbles due to direct contact condensation can cause breakdown of the stratified layers and lead to mixing of the pool water. Accurate prediction of the pool thermal-hydraulics in such scenarios presents a computational challenge. Lumped-parameter models have no capability to predict temperature distribution of water pool during thermal stratification development. While high-order-accurate CFD (RANS, LES) methods are not practical due to excessive computing power needed to calculate 3D high-Rayleighnumber natural circulation flow in long transients. In the present work, a middleground approach is used, namely CFD-like model of the general purpose thermalhydraulic code GOTHIC. Each cell of 3D GOTHIC grid uses lumped parameter volume type closures for modeling of various heat and mass transfer processes at subgrid scale. We use GOTHIC to simulate POOLEX/PPOOLEX experiment, in order to (a) quantify errors due to GOTHIC's physical models and numerical schemes, and (b

Analysis of natural convection in volumetrically-heated melt pools

Energy Technology Data Exchange (ETDEWEB)

Sehgal, B.R.; Dinh, T.N.; Nourgaliev, R.R. [Royal Inst. of Tech., Stockholm (Sweden). Div. of Nuclear Power Safety

1996-12-01

Results of series of studies on natural convection heat transfer in decay-heated core melt pools which form in a reactor lower plenum during the progression of a core meltdown accident are described. The emphasis is on modelling and prediction of turbulent heat transfer characteristics of natural convection in a liquid pool with an internal energy source. Methods of computational fluid dynamics, including direct numerical simulation, were applied for investigation. Refs, figs, tabs.

Representation of a common 3-pool compartment model for N turnover of ruminants

International Nuclear Information System (INIS)

Ulbrich, M.

1989-01-01

On the basis of an existing 3-pool compartment model for the N turnover of lactating ruminants a method was elaborated for N turnover determination in non-lactating ruminants by measuring the 15 N frequency in NPN pool and without experimental measurements of the 15 N frequency in the amino acid pool

Atlantic Warm Pool Trigger for the Younger Dryas Climate Event

Science.gov (United States)

Abdul, N. A.; Mortlock, R. A.; Wright, J. D.; Fairbanks, R. G.; Teneva, L. T.

2011-12-01

There is growing evidence that variability in the size and heat content of the tropical Atlantic Warm Pool impacts circum-North Atlantic climate via the Atlantic Multi-decadal Oscillation mode (Wang et al., 2008). The Atlantic Warm Pool spans the Gulf of Mexico, Caribbean Sea and the western tropical North Atlantic. Barbados is located near the center of the tropical Atlantic Warm Pool and coupled ocean models suggest that Barbados remains near the center of the tropical Atlantic Warm Pool under varying wind stress simulations. Measurements of the oxygen isotope paleothermometer in Acropora palmata coral species recovered from cores offshore Barbados, show a 3oC monotonic decrease in sea surface temperature from 13106 ± 83 to 12744 ± 61 years before present (errors given as 2 sigma). This interval corresponds to a sea level rise from 71.4 meters to 67.1 meters below present levels at Barbados. The 3oC temperature decrease is captured in eight A. palmata specimens that are in stratigraphic sequence, 230Th/234U dated, and analyzed for oxygen isotopes. All measurements are replicated. We are confident that this is the warm pool equivalent of the Younger Dryas climate event. The initiation of this temperature drop in the Atlantic Warm Pool predates the Younger Dryas start in Greenland ice cores, reported to start at 12896 ± 138 years (relative to AD 2000) (Rasmussen et al., 2006), while few other Younger Dryas climate records are dated with similar accuracy to make the comparison. Rasmussen, S.O., Andersen, K.K., Svensson, A.M., Steffensen, J.P., Vinther, B.M., Clausen, H.B., Siggaard-Andersen, M.L., Johnsen, S.J., Larsen, L.B., Dahl-Jensen, D., Bigler, M., Röthlisberger, R., Fischer, H., Goto-Azuma, K., Hansson, M.E., and Ruth, U., 2006, A new Greenland ice core chronology for the last glacial termination: J. Geophys. Res., v. 111, p. D06102. Wang, C., Lee, S.-K., and Enfield, D.B., 2008, Atlantic Warm Pool acting as a link between Atlantic Multidecadal

Removal of volatile iodine from gas bubbles rising in water pools: review and assessment of pool scrubbing codes

International Nuclear Information System (INIS)

Polo, J.; Herranz, L.E.; Peyres, V.; Escudero, M.

1996-01-01

During a hypothetical nuclear reactor accident with core damage the fission products released from the degrading fuel bundles often pass through aqueous beds before entering the containment, mitigating in part the source term. Several computer codes have been developed for predicting the fission product and aerosols removal in pool scrubbing scenarios. In addition to particle removal, these codes simulate the retention of some volatile iodine compounds. Nonetheless, experimental data on the matter are rather scarce and further validation remains to be done. In this work a review of volatile iodine removal models included in SPARC and BUSCA codes is presented. Besides, the results and discussions of a validation of both codes against the available experimental data are summarized. SPARC and BUSCA codes model the diffusion of iodine toward the bubble interface by using the film penetration theory, which assumes a double layer gas-liquid at the interface. However, there are some differences between the two models, mainly related to the boundary conditions in the aqueous volume for the diffusion of molecular iodine. In SPARC, a set of fast reactions in the liquid phase control both the molecular iodine concentration in the pool and the partition coefficient of iodine at the interface. Thus, the aqueous chemistry plays an important role in the boundary conditions for the diffusion process. On the contrary, the BUSCA model has no chemical considerations at all, and assumes a null iodine concentration in the water bulk. Several sensitivity studies have been made in order to weight the effect of these differences. The variables examined in these studies were the pool temperature and the incoming iodine concentration in the pool. Additionally, sensitivity studies focused on the steam mass fraction of the injected gas were performed to study the effect of the different approach of both models for the condensation process. The results showed a different sensitivity of SPARC

Remote sensing of LAI, chlorophyll and leaf nitrogen pools of crop- and grasslands in five European landscapes

KAUST Repository

Boegh, E.; Houborg, Rasmus; Bienkowski, J.; Braban, C.F.; Dalgaard, T.; Van, Dijk, N.; Dragosits, U.; Holmes, E.; Magliulo, V.; Schelde, K.; Di, Tommasi, P.; Vitale, L.; Theobald, M.R.; Cellier, P.; Sutton, M.A.

2013-01-01

as the relationships between spectral vegetation indices (SVIs) and field measurements. When the range of surface types increased, the REGFLEC results were in better agreement with field data than the empirical SVI regression models. Selecting only homogeneous canopies with uniform CHLl distributions as reference data for evaluation, REGFLEC was able to explain 69% of LAI observations (rmse Combining double low line 0.76), 46% of measured canopy chlorophyll contents (rmse Combining double low line 719 mg m-2) and 51% of measured canopy nitrogen contents (rmse Combining double low line 2.7 g m-2). Better results were obtained for individual landscapes, except for Italy, where REGFLEC performed poorly due to a lack of dense vegetation canopies at the time of satellite recording. Presence of vegetation is needed to parameterize the REGFLEC model. Combining REGFLEC- and SVI-based model results to minimize errors for a "snap-shot" assessment of total leaf nitrogen pools in the five landscapes, results varied from 0.6 to 4.0 t km-2. Differences in leaf nitrogen pools between landscapes are attributed to seasonal variations, extents of agricultural area, species variations, and spatial variations in nutrient availability. In order to facilitate a substantial assessment of variations in Nl pools and their relation to landscape based nitrogen and carbon cycling processes, time series of satellite data are needed. The upcoming Sentinel-2 satellite mission will provide new multiple narrowband data opportunities at high spatiooral resolution which are expected to further improve remote sensing capabilities for mapping LAI, CHLl and Nl. Author(s) 2013. CC Attribution 3.0 License.

Remote sensing of LAI, chlorophyll and leaf nitrogen pools of crop- and grasslands in five European landscapes

KAUST Repository

Boegh, E.

2013-10-07

as the relationships between spectral vegetation indices (SVIs) and field measurements. When the range of surface types increased, the REGFLEC results were in better agreement with field data than the empirical SVI regression models. Selecting only homogeneous canopies with uniform CHLl distributions as reference data for evaluation, REGFLEC was able to explain 69% of LAI observations (rmse Combining double low line 0.76), 46% of measured canopy chlorophyll contents (rmse Combining double low line 719 mg m-2) and 51% of measured canopy nitrogen contents (rmse Combining double low line 2.7 g m-2). Better results were obtained for individual landscapes, except for Italy, where REGFLEC performed poorly due to a lack of dense vegetation canopies at the time of satellite recording. Presence of vegetation is needed to parameterize the REGFLEC model. Combining REGFLEC- and SVI-based model results to minimize errors for a "snap-shot" assessment of total leaf nitrogen pools in the five landscapes, results varied from 0.6 to 4.0 t km-2. Differences in leaf nitrogen pools between landscapes are attributed to seasonal variations, extents of agricultural area, species variations, and spatial variations in nutrient availability. In order to facilitate a substantial assessment of variations in Nl pools and their relation to landscape based nitrogen and carbon cycling processes, time series of satellite data are needed. The upcoming Sentinel-2 satellite mission will provide new multiple narrowband data opportunities at high spatiooral resolution which are expected to further improve remote sensing capabilities for mapping LAI, CHLl and Nl. Author(s) 2013. CC Attribution 3.0 License.

Volume-heated boiling pool flow behavior and application to transition phase accident conditions

International Nuclear Information System (INIS)

Ginsberg, T.; Jones, O.C. Jr.; Chen, J.C.

1978-01-01

Observations of two-phase flow fields in volume-heated boiling pools are reported. Photographic observations, together with pool-average void fraction measurements are presented. Flow regime transition criteria derived from the measurements are discussed. The churn-turbulent flow regime was the dominant regime for superficial vapor velocities up to nearly five times the Kutateladze dispersal velocity. Within this range of conditions, a churn-turbulent drift flux model provides a reasonable prediction of the pool-average void fraction data. The results of the experiment and analyses are extrapolated to transition phase conditions. It is shown that intense pool boil-up could occur where the pool-average void fraction would be greater than 0.6 for steel vaporization rates equivalent to power levels greater than one percent of nominal LMFBR power density

Evaluation of Total Coliform, Fecal Coliform and Residual Chlorine in Swimming Pools in Kermanshah on the Season, the type of Pool, Disinfection System and Source of Water Supply in the during of three years (2010-2012

Directory of Open Access Journals (Sweden)

K SHarafi

2014-11-01

From the results , although the pools of water quality parameters has been studied in almost ideal But in summer, especially on a female pools and pools with wells water supply source than other pools , to be more oversight .

Mixed convection and stratification phenomena in a heavy liquid metal pool

Energy Technology Data Exchange (ETDEWEB)

Tarantino, Mariano, E-mail: mariano.tarantino@enea.it [Italian National Agency for New Technologies, Energy and Sustainable Economic Development, C.R. ENEA Brasimone (Italy); Martelli, Daniele; Barone, Gianluca [Dipartimento di Ingegneria Civile e Industriale, University of Pisa, Largo Lucio Lazzarino, 1-56100 Pisa Italy (Italy); Di Piazza, Ivan [Italian National Agency for New Technologies, Energy and Sustainable Economic Development, C.R. ENEA Brasimone (Italy); Forgione, Nicola [Dipartimento di Ingegneria Civile e Industriale, University of Pisa, Largo Lucio Lazzarino, 1-56100 Pisa Italy (Italy)

2015-05-15

Highlights: • Results related to experiments reproducing PLOHS + LOF accident in CIRCE pool facility. • Vertical thermal stratification in large HLM pool. • Transition from forced to natural circulation in HLM pool under DHR conditions. • Heat transfer coefficient measurement in HLM pin bundle. • Nusselt numbers calculations and comparison with correlations. - Abstract: This work deals with an analysis of the first experimental series of tests performed to investigate mixed convection and stratification phenomena in CIRCE HLM large pool. In particular, the tests concern the transition from nominal flow to natural circulation regime, typical of decay heat removal (DHR) regime. To this purpose the CIRCE pool facility has been updated to host a suitable test section in order to reproduce the thermal-hydraulic behaviour of a HLM pool-type reactor. The test section basically consists of an electrical bundle (FPS) made up of 37 pins arranged in a hexagonal wrapped lattice with a pitch diameter ratio of 1.8. Along the FPS active length, three sections were instrumented to monitor the heat transfer coefficient along the bundle as well as the cladding temperatures at different ranks of the sub-channels. This paper reports the experimental data as well as a preliminary analysis and discussion of the results, focusing on the most relevant tests of the campaign, namely Test I (48 h) and Test II (97 h). Temperatures along three sections of the FPS and at inlet and outlet sections of the main components were reported and the Nusselt number in the FPS sub-channels was investigated together with the void fraction in the riser. Concerning the investigation of in-pool thermal stratification phenomena, the temperatures in the whole LBE pool were monitored at different elevations and radial locations. The analysis of experimental data obtained from Tests I and II underline the occurrence of thermal stratification phenomena in the region placed between the outlet sections of