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Sample records for small access riser

  1. Tools for Inspecting and Sampling Waste in Underground Radioactive Storage Tanks with Small Access Riser Openings

    International Nuclear Information System (INIS)

    Nance, T.A.

    1998-01-01

    Underground storage tanks with 2 inches to 3 inches diameter access ports at the Department of Energy's Savannah River Site have been used to store radioactive solvents and sludge. In order to close these tanks, the contents of the tanks need to first be quantified in terms of volume and chemical and radioactive characteristics. To provide information on the volume of waste contained within the tanks, a small remote inspection system was needed. This inspection system was designed to provide lighting and provide pan and tilt capabilities in an inexpensive package with zoom abilities and color video. This system also needed to be utilized inside of a plastic tent built over the access port to contain any contamination exiting from the port. This system had to be build to travel into the small port opening, through the riser pipe, into the tank evacuated space, and out of the riser pipe and access port with no possibility of being caught and blocking the access riser. Long thin plates were found in many access riser pipes that blocked the inspection system from penetrating into the tank interiors. Retrieval tools to clear the plates from the tanks using developed sampling devices while providing safe containment for the samples. This paper will discuss the inspection systems, tools for clearing access pipes, and solvent sampling tools developed to evaluate the tank contents of the underground solvent storage tanks

  2. Continuous composite riser

    Energy Technology Data Exchange (ETDEWEB)

    Slagsvold, L. [ABB Offshore Systems (Norway)

    2002-12-01

    The industry is now looking at developing reserves in waters depths of up to 3000 m (10000 ft). When moving into deeper waters the un-bonded flexible riser becomes very heavy and introduces large hang-off forces on the vessel. We are therefore investigating riser concepts incorporating new materials and with a simpler cross section that can be used for floating production. Advanced composite materials have properties such as, low weight, high strength, good durability and very good fatigue performance. Composite materials are slowly being exploited in the oil industry; they are being prototype tested for drilling risers and small diameter lines. Part of the process for the industry to accept larger diameter production risers made out of composite materials is to understand both the advantages and limitations. A new continuous composite riser system is being developed which capitalizes on the technical benefits of this material while addressing the known constraints. The fully bonded riser is being developed for ultra deep waters and its' characteristics include high temperature (160 deg C), high pressure (500 barg min), light weight, chemical resistant, good insulation, excellent fatigue characteristics and installation by reeling. The concept is based on the use of a thermoplastic liner together with a thermoplastic carbon fibre composite. This paper summarises the ongoing development, which has a goal to manufacture and qualify an 8'' riser, and includes all the steps in a production process from material qualification to the winding process and analytical modelling. (author)

  3. An accurate and computationally efficient small-scale nonlinear FEA of flexible risers

    OpenAIRE

    Rahmati, MT; Bahai, H; Alfano, G

    2016-01-01

    This paper presents a highly efficient small-scale, detailed finite-element modelling method for flexible risers which can be effectively implemented in a fully-nested (FE2) multiscale analysis based on computational homogenisation. By exploiting cyclic symmetry and applying periodic boundary conditions, only a small fraction of a flexible pipe is used for a detailed nonlinear finite-element analysis at the small scale. In this model, using three-dimensional elements, all layer components are...

  4. Engineering study - installation of new risers in Single-Shell Tanks

    International Nuclear Information System (INIS)

    Magruder, W.J.

    1994-08-01

    A sampling program is being developed to characterize the 149 underground SSTs on the Hanford Site. The sampling effort will require access to the tank interior in a minimum of two locations per tank. Some of the risers suitable for sampling are either unavailable or are not in locations for proper characterization of the tank contents. Additional risers will be required in the SSTs to support the tank characterization sampling program. The purpose of this engineering study is to review alternatives for installation of new riser in the SSTs

  5. How to inspect platform risers: an effective approach and new challenges

    International Nuclear Information System (INIS)

    Agthoven, Robert van

    2007-01-01

    Ageing risers on offshore platforms, designed and built several decades ago, were until recently hard to inspect or not inspectable at all. This was due to their layout or ID geometry changes prohibiting the use of product propelled intelligent pigs, which are frequently used, on long distance pipelines. Growing concerns about reliability and safety, as well as environmental pressure, are the impetus for operators of offshore platforms to check the condition of the risers, which until now could not be inspected. This paper describes a few solutions to enter these 'non-inspect-able' risers to check their condition by using special small diameter cable operated tools. These new miniature cable tools are spin-offs from the well-known cable (tether, umbilical) tools introduced more than two decades ago by RTD for the inspection of (off)-loading lines. The first generation gravity driven small diameter riser inspection tools were designed to inspect the vertical section of the riser only. On-going development has resulted in a second generation of riser inspection tools which can now enter a few hundred metres into the horizontal connecting pipeline on the sea-floor by using a small, but powerful, crawler. With this ability these tools are the only solution for riser-pipes and relatively short connecting pipelines which terminate at a T-or Y-connection in the vicinity of the platform. All riser inspection tools apply ultrasonics to quantify wall thickness and corrosion. A novel TOFD (Time Of Flight Diffraction) module can be applied as an option to inspect in the circumferential weld area. All cable tools have a reinforced cable, which is used for tool control and retrieval. A strong advantage of these cable tools is that they provide on-line results and allow on-site evaluation. Since the introduction of these new tools considerable experience has been gained. The history of development and several typical cases of applications are given in this paper. In addition

  6. Riser pipe elevator

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, W.; Jimenez, A.F.

    1987-09-08

    This patent describes a method for storing and retrieving a riser pipe, comprising the steps of: providing an upright annular magazine comprised of an inside annular wall and an outside annular wall, the magazine having an open top; storing the riser pipe in a substantially vertically oriented position within the annular magazine; and moving the riser pipe upwardly through the open top of the annular magazine at an angle to the vertical along at least a portion of the length of the riser pipe.

  7. Modelling and Simulation of Coking in the Riser of an Industrial ...

    African Journals Online (AJOL)

    Modelling and Simulation of Coking in the Riser of an Industrial Fluid Catalytic Cracking (FCC) Unit. ... Log in or Register to get access to full text downloads. ... The yields of LCO, gasoline, gas and coke that were predicted by the model for industrial risers were ... Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  8. Composite risers for deep-water offshore technology: Problems and prospects. 1. Metal-composite riser

    Science.gov (United States)

    Beyle, A. I.; Gustafson, C. G.; Kulakov, V. L.; Tarnopol'skii, Yu. M.

    1997-09-01

    Prospects for the application of advanced composites in the offshore technology of oil production are considered. The use of composites in vertical pipelines-risers seems to be the most efficient. The operating loads are studied and the attendant problems are formulated. A comparative analysis of the characteristics of metal, composite, and metal-composite deep-water risers is presented. A technique is developed for designing multilayered risers, taking into account the action of internal and external pressures, gravity, and the axial tensile force created by tensioners, as well as the residual technological stresses due to the difference in coefficients of thermal expansion, physical-chemical shrinkage, and force winding. Numerical estimations are given for a two-layered riser with an inner metal layer of steel, titanium, or aluminum alloys and a composite layer of glass- or carbon-fiber plastics formed by circumferential winding. It is shown that the technological stresses substantially affect the characteristics of the riser.

  9. Structural analysis of multiport riser 5A installation on tank 241SY101

    Energy Technology Data Exchange (ETDEWEB)

    Strehlow, J.P.

    1994-09-16

    The Tank 101-SY multiport riser assembly in the 241-SY-101 waste tank will replace the existing 42 inch riser with four smaller ports. Each smaller port can be used independently to access the tank interior with equipment and instruments needed to mitigate the concentration of hydrogen in the tank. This document provides a design report on the structural evaluation of the multiport riser assembly as well as its anchorage. The multiport riser assembly is a steel structure installed directly above the 42-inch riser and sealed at the existing riser flange. The assembly is structurally supported by the concrete pad placed around the 42 inch riser. The multiport riser assembly will provide two 8-inch penetrations, one 12-inch penetration and one 24-inch penetration. Each penetration will have a shielding plate. These penetrations will be used to insert equipment such as a sonic probe into the tank. In addition to normal loads, non-reactor Safety Class 1 structures, systems and components are to withstand the effects of extreme environmental loads including Design Basis Earthquake (DBE), Design Basis Wind (DBW), Design Basis Flood, Volcanic Eruptions and other abnormal loads considered on a case by case basis. Non-reactor Safety Class 2, 3 and 4 structures, systems and components are those that are not Safety Class 1 and are respectively specified as onsite safety related, occupational safety related and non-safety related items. The 241-SY-101 tank is considered as a non-reactor Safety Class 1 structure. The multiport riser assembly is considered as a non-reactor Safety Class 2 structure since it serves to contain the radioactive and toxic materials under normal operating conditions. However, the pressure relief doors provided on the assembly are considered as Safety Class 1 structures.

  10. Advances in riser and pipeline technologies

    Energy Technology Data Exchange (ETDEWEB)

    Kan, Wan C.; Mortazavi, Mehrdad; Weir, Michael S. [ExxonMobil Development Company, Dallas, TX (United States)

    2009-12-19

    As oil and gas production continues to move into new frontier areas, novel applications of the existing riser and pipeline technologies need to be developed to meet the often more stringent requirements encountered in these environments. The challenges include ultra deep water, harsh environments, aggressive fluid conditions, and local content objectives, etc. They will require industry to constantly extend, expand, and enhance the broad range of solution options. Also, the existing design criteria in industry may need to be revised or new criteria may need to be developed to satisfy these needs. Exxon Mobil (Em) employs, and works with others in industry to promote robust design and operating practices. This approach requires in-depth understanding, sound engineering principles, advanced analysis, uncertainty management, and supportive qualification test data. It enables confident selection, extrapolation, and innovation of technologies to address new riser system and pipeline challenges. Focus on fundamental is imperative to ensure integrity of the selected systems during fabrication, installation, and operation phases. Recent and past project experience in deep water Gulf of Mexico and West Africa provides many successful examples of this approach. This paper reviews several examples of the key riser system and pipeline technology enhancements recently achieved by EM to provide confidence in addressing technical and project application challenges. Riser system technology enhancements addressed in this paper include steel catenary riser (SCR) application on turret-moored FPSO with severe motions, pipe-in-pipe (PIP) hybrid production riser to effectively manage gas lift and flow assurance requirements, irregular wave analysis methodology for flexible risers and umbilicals to reduce conservatism, and qualification of riser and pipeline VIV prediction and mitigation methods. Pipeline technology enhancements detailed in this paper include lateral buckling prediction

  11. Fluid dynamics characterization of riser in a FCC cold flow model using gas radiotracer

    International Nuclear Information System (INIS)

    Santos, Valdemir A. dos; Lima, Emerson A.O.

    2013-01-01

    Was carried out the characterization of a diameter small riser of a cold flow model of a circulating fluidized bed (CFB), with aid of a radioactive tracer. Compressed air and catalytic cracking of petroleum flow through solids pneumatic transport regime, made of transparent material (glass, acrylic, PVC, polycarbonate) for study of problems in Fluid Catalytic Cracking (FCC) unit and development of methods of measurement of fluid dynamic parameters. The CFB model consisted of a mixer component solid-gas (compressed air at 25 deg C and 200 kN/m 2 ; cracking catalyst with an average diameter of 72μm and specific mass of 1,500 kg/m 3 ), comprising a riser pipe glass 0.02m internal diameter and 1.8m height, a gas solid separation vessel by flash effect, with the filter in the gas outlet, and a return column (a glass tube with an internal diameter of 0.0254m) to redirect the catalyst for the riser base. Recorded data allowed studies on residence time distribution of the gaseous phase in the riser, with the identification and characterization of the flow of gas-solid components in the CFB riser of small diameter. A plug flow type with deviations due to back mixing of catalyst close to the walls, associated with the density difference between this component was observed. (author)

  12. Severe Slugging in Air-Water Hybrid Riser System

    Directory of Open Access Journals (Sweden)

    Jing Gong

    2014-11-01

    Full Text Available In the subsea pipeline gathering system, severe slugging flow is prone to occur. Severe slugging flow brings major threat to production and flow assurance in oil and gas industry due to periodical pressure oscillation and large liquid volume. Currently many researchers pay much more attention on L-shaped riser, catenaries, and S-shaped riser; little research has been made on hybrid riser, which is applied in the Africa West and Gulf of Mexico oil fields. Flow characteristics simulation for hybrid riser is made in this paper, using the one-dimensional and quasi-equilibrium model to simulate not only the riser-base pressure, severe slugging period, and the liquid slug length of the whole system but also base-pressure in the flexible pipe section. The calculated results match well with the experiment data. Besides, the influence of flexible pipe to the severe slugging characteristics of hybrid riser system is analyzed, which are significant for the determination of riser structure.

  13. Le comportement mécanique des risers. Influence des principaux paramètres Mechanical Behaviour of Marine Risers Mode of Influence of Principal Parameters

    Directory of Open Access Journals (Sweden)

    Sparks C.

    2006-11-01

    Full Text Available Cet article a pour but de déterminer les principaux paramètres qui gouvernent le comportement mécanique des risers de forage et de production, et d'expliquer pourquoi et comment ils interviennent. Une compréhension claire de ces influences permet d'optimiser rapidement un riser donné sans avoir recours à un grand nombre d'analyses par ordinateur. Celui qui conçoit un riser est principalement préoccupé par les points suivants : - niveaux de contraintes dans la partie courante du riser ; - mouvements angulaires à la base du riser (ou moments, dans le cas d'une liaison rigide ; - mouvements relatifs au niveau de la liaison plate-forme/riser. La méthode utilisée dans cet article consiste à établir des expressions analytiques valables pour des risers simplifiés. Les conclusions tirées de ces expressions ont ensuite été verifiéés à l'aide d'un programme de calcul capable de simuler le comportement dynamique d'un riser dans des configurations variées. This paper attempts to identify the principal parameters, that influence the behavior of drilling and production risers and to explain how and why they do so. Clear understanding of these influences enable particular risers to be optimised rapidly without recourse to an inordinate number of computer analyses. The points of greatest concern, to the riser designer, are: a Stress levels in the main length of riser. (b Angular movement at sea bed (or moment, if the connection is rigid. (c Relative movement at riser/platform connection. The approach, used in the paper, has been ta derive analytical expressions, for simplified riser cases. Conclusions drawn from these expressions have then been checked for validity, by using a dynamic analysis computer program to simulate a wide range of cases.

  14. Riser configuration, Tank 241-A-105, light duty utility arm

    International Nuclear Information System (INIS)

    Boucher, T.D.

    1994-01-01

    The light-duty utility arm (LDUA) is a seven-joint stainless steel robotic arm with a payload capacity of 75 lb. The robotic arm is deployed vertically with a maximum vertical reach of 63 ft. and a maximum horizontal reach of 13.5 ft. The functional requirements of the LDUA system are mapping and characterization of waste in Hanford single-shell tanks (SST) before and during waste retrieval. The LDUA system consists of a mobile deployment system (MDS), a vertical positioning mast (VPM), a tank riser interface confinement (TRIC), the LDUA, and a controller subsystem or support trailer. Currently, the system is in design and is subject to change; however, the LDUA or robotic arm will be deployed through a 12-in. riser above the tank dome. Field trips were performed to gather specifics for future deployment of the LDUA in Tank 241-A-105. The purpose of this report is to support two previous reports for the investigation of SSTs for deployment of the LDUA system. The first report identified the availability of risers while the second report identified the availability of Tanks 241-A-105, 241-A-S-109, 241-A-T-101, and 241-A-T-109 for deployment of the LDUA system. The second report also identified those 4- and 12-in. risers that could be used for deployment of the LDUA and camera system. This report addresses accessibility to the 241-A Tank Farm and the usability of the Tank 241-A-105 risers. The following information for assisting in the design and deployment of the LDUA will be discussed in this report: radiation survey; flange identification; high resolution video; computer simulated model; and field survey

  15. Steel catenary risers supported by subsurface buoy

    OpenAIRE

    Adebayo, Addayo

    2011-01-01

    Master's thesis in Offshore technology Oil and gas exploration and production activities in deep and ultra deep waters in hostile environments necessitates the need to develop innovative riser systems capable of ensuring transfer of fluids from the seabed to a floating vessel and vice versa, with little or no issues with respect to influences of environmental loads and vessel motions. Over the years, studies have shown that the conventional flexible riser and steel catenary riser config...

  16. Reliability analysis of wake-induced collision of flexible risers

    OpenAIRE

    Fu, Ping; Leira, Bernt Johan; Myrhaug, Dag

    2017-01-01

    Collision between risers is an important design and operational concern, especially in deep water since the probability of collision tends to increase as the riser length increases. Riser collision is due to the joint effects of many processes, i.e. environmental loads, hydrodynamic interference and surface floater motions and the most of them are stochastic processes. This paper provides an approach for estimating the failure probability of riser collision by considering these joint effects ...

  17. Remote installation of risers on underground nuclear waste storage tanks

    International Nuclear Information System (INIS)

    Jackson, J.P.; Gessner, R.F.

    1988-03-01

    The West Valley Demonstration Project was established to solidify 2120 m 3 (560,000) gallons of high-level nuclear waste generated during six years of commercial nuclear fuel reprocessing. This liquid will be processed to remove radioactive elements which, with the remaining sludge, will be combined with glass formers and be converted into borosilicate glass. Risers were installed on the high-level tank for installation of pumps which will be used to remove the liquid and sludge. The extensive use of remote technology was required to install the risers and to minimize operator exposure to high levels of radiation and contamination. The riser installation required remotely: drilling through two feet of concrete shielding; installing pump access pipes which are welded to the tank top; and cutting holes in tanks located 3658 mm (12) feet below ground. These operations were successfully completed 13 times without exposing personnel to high-level radiation or contamination. Specially designed remote equipment was developed for each step of this operation. Extensive operator training in the use of this equipment was performed on a tank with low radiation prior to work on the high-level tank. This paper discusses the application of remote technology that assured a quality job was safely accomplished. 3 refs., 18 figs., 2 tabs

  18. Application of corrosion screening tools for riser inspection

    International Nuclear Information System (INIS)

    Zamir Mohamed Daud; Vijayan, S.

    2003-01-01

    As offshore facilities approach the end of their design life, owners would like to assess the condition and integrity of plant and equipment. Detailed inspection, including non-destructive testing (NDT), are implemented and results are utilised for predictive maintenance and estimating useful remaining life. Except for risk based inspection, the extent of surface coverage required would be more compared to inspection of pre-determined spots. Risers, for example, usually have several layers of coating that prevent use of conventional techniques for inspection of corrosion. Complete coverage requires access (including removal coatings and insulation). Inspection utilising the conventional NDT tools can be very slow and expensive. However, recent advances have forwarded the use of specialised NDT techniques that were developed for inspection of corrosion under insulation (CUI). This paper details two screening inspection tools, LIXI Profiler and RTD-INCOTEST that have been applied to inspection of risers. LIXI Profiler is based on attenuation of penetrating radiation by materials, and RTD-INCOTEST is based on decay of pulsed eddy current in materials. (Author)

  19. Natural Frequencies and Mode Shapes of Statically Deformed Inclined Risers

    KAUST Repository

    Alfosail, Feras

    2016-10-15

    We investigate numerically the linear vibrations of inclined risers using the Galerkin approach. The riser is modeled as an Euler-Bernoulli beam accounting for the nonlinear mid-plane stretching and self-weight. After solving for the initial deflection of the riser due to self-weight, we use a Galerkin expansion employing 15 axially loaded beam mode shapes to solve the eigenvalue problem of the riser around the static equilibrium configuration. This yields the riser natural frequencies and corresponding exact mode shapes for various values of inclination angles and tension. The obtained results are validated against a boundary-layer analytical solution and are found to be in good agreement. This constitutes a basis to study the nonlinear forced vibrations of inclined risers.

  20. Prevention of pulsations caused by flexible risers

    NARCIS (Netherlands)

    Belfroid S.P.C; Golliard, J.; Korst, H.J.C.

    2013-01-01

    In the last few decades, flexible risers have increasingly been used in the offshore oil and gas industry. In gas applications these risers can generate high amplitude tonal pressure fluctuations when the gas velocity reaches a threshold value. The resulting pressure fluctuations can then cause high

  1. 1000 meters water depth rigid TLP riser; Riser rigido de plataforma de pernas atirantadas para lamina d'agua de 1000 metros

    Energy Technology Data Exchange (ETDEWEB)

    Braga, Mauro Jacinto Pastor

    1990-07-01

    A procedure to estimate the fatigue life of a TLP riser in 1000 meters water depth based on a hydro-elastic analysis of an integrated riser-TLP model in the time domain is presented . The computational architecture is shown that makes it feasible to process and store the great amount of data involved. The procedure is applied to a 1000 meters water depth TLP with a set of 40 risers 8 inches in diameter equipped with a floatation layer. (author)

  2. Flexible riser integrity management: areas of concern and applications

    Energy Technology Data Exchange (ETDEWEB)

    Podskarbi, Mateusz [Schlumberger Servicos de Petroleo Ltda., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    Flexible risers are key enables for both deep water and shallow water offshore production developments. Number of flexible risers installed worldwide is into several thousands with two main concentration areas - offshore Brazil and North Sea. Flexible risers are subject to significant loads including environmental impacts, vessel motions, internal temperature and pressure as well as substantial installation loads. Excessive loads of one type or a combination of various types of loads can cause damage to the flexible that can lead to a catastrophic failure. Industry observed number of failures increasing in recent years. Operators and manufacturing companies are taking various steps to address this issue. One of possible approaches is to use monitoring instrumentation to measure riser response and integrity in real time. This paper reviews various types of flexible riser damage mechanisms caused by impact damage, corrosion, excessive pressure, armor wire rupture, compromising flexible riser minimum bend radius, excessive fatigue loading, etc. Failure mechanisms are reviewed with particular focus on the consequences that it causes in terms of risk to the infrastructure and detectable changes. Further part of the paper is focused on monitoring techniques employed and available to detect particular types of failure mechanisms. Systematic review of the monitoring techniques is provided with specific attention given to ability of these techniques to provide early warnings of riser failure. Evaluation of monitoring techniques versus modes of operation and failure mechanism is key to selecting appropriate system that ensures effectiveness of the integrity management program. (author)

  3. Composite Risers for Deepwater Applications Risers composites pour applications en mer profonde

    Directory of Open Access Journals (Sweden)

    Metivaud G.

    2006-11-01

    Full Text Available This paper is devoted to the high performance composite tubes developed by the Institut Français du Pétrole (IFP and Aerospatiale for deepwater risers applications. The design principles of the tubes are first presented, along with results of preliminary work carried out as part of the initial feasibility study. Applications of composite tubes to drilling riser Kill and Choke lines and to TLP production risers, both of which have been studied in detail, are then described. Technical and operational advantages obtained from such applications are discussed. Cet article présente les travaux réalisés par l'Institut Français du Pétrole et l'Aerospatiale dans le domaine des tubes composites haute performance pour les applications aux liaisons fond-surface de forage et de production en mer profonde. Les matériaux composites avancés sont une classe de matériaux très particulière, présentant à la fois des caractéristiques mécaniques élevées et une densité spécifique faible. Ils sont utilisés principalement par les industries de l'aéronautique et de l'espace, mais l'industrie pétrolière en mer profonde est un secteur où ils peuvent trouver dans l'avenir des applications très intéressantes, notamment les tubes de risers. Les tubes de risers pétroliers en mer présentent en effet une gamme de spécifications élevées (diamètres, pression, traction, fatigue dans un environnement sévère et leur poids suspendu peut pénaliser fortement les systèmes de forage ou de production par grande profondeur d'eau. Un premier concept de tube composite haute performance a été développé par IFP et Aerospatiale au début des années 1980 ; sa partie courante, réalisée par enroulement filamentaire de fibres de verre R ou de fibres de carbone, et son système d'embout ont été soumis à une série d'essais mécaniques (pression interne jusqu'à 105 MPa, traction supérieure à 1 000 kN pour un diamètre nominal de 0,1 m, millions de

  4. Numerical Simulation of the Vortex-Induced Vibration of A Curved Flexible Riser in Shear Flow

    Science.gov (United States)

    Zhu, Hong-jun; Lin, Peng-zhi

    2018-06-01

    A series of fully three-dimensional (3D) numerical simulations of flow past a free-to-oscillate curved flexible riser in shear flow were conducted at Reynolds number of 185-1015. The numerical results obtained by the two-way fluid-structure interaction (FSI) simulations are in good agreement with the experimental results reported in the earlier study. It is further found that the frequency transition is out of phase not only in the inline (IL) and crossflow (CF) directions but also along the span direction. The mode competition leads to the non-zero nodes of the rootmean- square (RMS) amplitude and the relatively chaotic trajectories. The fluid-structure interaction is to some extent reflected by the transverse velocity of the ambient fluid, which reaches the maximum value when the riser reaches the equilibrium position. Moreover, the local maximum transverse velocities occur at the peak CF amplitudes, and the values are relatively large when the vibration is in the resonance regions. The 3D vortex columns are shed nearly parallel to the axis of the curved flexible riser. As the local Reynolds number increases from 0 at the bottom of the riser to the maximum value at the top, the wake undergoes a transition from a two-dimensional structure to a 3D one. More irregular small-scale vortices appeared at the wake region of the riser, undergoing large amplitude responses.

  5. Numerical Modeling and Mechanical Analysis of Flexible Risers

    Directory of Open Access Journals (Sweden)

    J. Y. Li

    2015-01-01

    Full Text Available ABAQUS is used to create a detailed finite element model for a 10-layer unbonded flexible riser to simulate the riser’s mechanical behavior under three load conditions: tension force and internal and external pressure. It presents a technique to create detailed finite element model and to analyze flexible risers. In FEM model, all layers are modeled separately with contact interfaces; interaction between steel trips in certain layers has been considered as well. FEM model considering contact interaction, geometric nonlinearity, and friction has been employed to accurately simulate the structural behavior of riser. The model includes the main features of the riser geometry with very little simplifying assumptions. The model was solved using a fully explicit time-integration scheme implemented in a parallel environment on an eight-processor cluster and 24 G memory computer. There is a very good agreement obtained from numerical and analytical comparisons, which validates the use of numerical model here. The results from the numerical simulation show that the numerical model takes into account various details of the riser. It has been shown that the detailed finite element model can be used to predict riser’s mechanics behavior under various load cases and bound conditions.

  6. Dynamic response of a riser under excitation of internal waves

    Science.gov (United States)

    Lou, Min; Yu, Chenglong; Chen, Peng

    2015-12-01

    In this paper, the dynamic response of a marine riser under excitation of internal waves is studied. With the linear approximation, the governing equation of internal waves is given. Based on the rigid-lid boundary condition assumption, the equation is solved by Thompson-Haskell method. Thus the velocity field of internal waves is obtained by the continuity equation. Combined with the modified Morison formula, using finite element method, the motion equation of riser is solved in time domain with Newmark-β method. The computation programs are compiled to solve the differential equations in time domain. Then we get the numerical results, including riser displacement and transfiguration. It is observed that the internal wave will result in circular shear flow, and the first two modes have a dominant effect on dynamic response of the marine riser. In the high mode, the response diminishes rapidly. In different modes of internal waves, the deformation of riser has different shapes, and the location of maximum displacement shifts. Studies on wave parameters indicate that the wave amplitude plays a considerable role in response displacement of riser, while the wave frequency contributes little. Nevertheless, the internal waves of high wave frequency will lead to a high-frequency oscillation of riser; it possibly gives rise to fatigue crack extension and partial fatigue failure.

  7. Evaluation of riser 14 temperature response

    International Nuclear Information System (INIS)

    OGDEN, D.M.

    1999-01-01

    The initial sluicing activities of Project WRSS resulted in a two month increase in temperatures as measured by the Riser 14 thermocouple tree of tank 241-C-106. While this increase was anticipated, the maximum temperature was higher than expected. An evaluation was performed to determine if adequate subcooling exists in the waste to continue sluicing activities. It was determined that a minimum of 10 F subcooling exists in the waste and that the higher Riser 14 temperatures were the result of higher than assumed waste saturation temperature

  8. FCC riser quick separation system: a review

    Directory of Open Access Journals (Sweden)

    Zhi Li

    2016-10-01

    Full Text Available Abstract The riser reactor is the key unit in the fluid catalytic cracking (FCC process. As the FCC feedstocks become heavier, the product mixture of oil, gas and catalysts must be separated immediately at the outlet of the riser to avoid excessive coking. The quick separation system is the core equipment in the FCC unit. China University of Petroleum (Beijing has developed many kinds of separation system including the fender-stripping cyclone and circulating-stripping cyclone systems, which can increase the separation efficiency and reduce the pressure drop remarkably. For the inner riser system, a vortex quick separation system has been developed. It contains a vortex quick separator and an isolated shell. In order to reduce the separation time, a new type of separator called the short residence time separator system was developed. It can further reduce the separation time to less than 1 s. In this paper, the corresponding design principles, structure and industrial application of these different kinds of separation systems are reviewed. A system that can simultaneously realize quick oil gas separation, quick oil gas extraction and quick pre-stripping of catalysts at the end of the riser is the trend in the future.

  9. Preliminary optimal configuration on free standing hybrid riser

    Directory of Open Access Journals (Sweden)

    Kyoung-Su Kim

    2018-05-01

    Full Text Available Free Standing Hybrid Riser (FSHR is comprised of vertical steel risers and Flexible Jumpers (FJ. They are jointly connected to a submerged Buoyancy Can (BC. There are several factors that have influence on the behavior of FSHR such as the span distance between an offshore platform and a foundation, BC up-lift force, BC submerged location and FJ length.An optimization method through a parametric study is presented. Firstly, descriptions for the overall arrangement and characteristics of FSHR are introduced. Secondly, a flowchart for optimization of FSHR is suggested. Following that, it is described how to select reasonable ranges for a parametric study and determine each of optimal configuration options. Lastly, numerical analysis based on this procedure is performed through a case study. In conclusion, the relation among those parameters is analyzed and non-dimensional parametric ranges on optimal arrangements are suggested. Additionally, strength analysis is performed with variation in the configuration. Keywords: Free standing hybrid riser, Hybrid riser system, Buoyancy can, Flexible jumper, Deepwater, Multi-body dynamics

  10. Features of a time domain simulation tool for rigid riser design

    Energy Technology Data Exchange (ETDEWEB)

    Morooka, Celso K.; Brandt, Dustin M. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Engenharia de Petroleo; Matt, Cyntia G.C.; Franciss, Ricardo [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    2008-07-01

    This paper present a number of numerical implementations designed for the analysis of rigid riser's static and dynamic behavior that includes the effects of vortex induced vibrations (VIV) and marine hydrodynamic loads in time domain. Features include the ability to consider pipe with a free-span utilizing a soil/riser interaction model. An implementation of a numerical coupling scheme to couple the vertical riser and platform dynamics was developed to allow prediction of the sub sea Blow-Out Preventer (BOP) re-entry into a sub sea petroleum well when drilling different phases of deep and ultra-deep wells. The developments contains support for the consideration of the Self Standing Hybrid Riser (SSHR) configuration which has been shown to be a promising riser configuration in deep and ultra-deep waters. A graphical interface was also created to better grasp the results and aid in the modeling, processing and to help analyze the numerical simulations, contributing to enhance agility and quality of the riser design and analysis processes. (author)

  11. CFD Simulation of Vortex Induced Vibration for FRP Composite Riser with Different Modeling Methods

    Directory of Open Access Journals (Sweden)

    Chunguang Wang

    2018-04-01

    Full Text Available Steel risers are widely used in offshore oil and gas industry. However, the production capacity and depths are limited due to their extreme weight and poor fatigue and corrosion resistance. Nowadays, it is confirmed that fiber reinforced polymer (FRP composite risers have apparent advantages over steel risers. However, the study of vortex induced vibration (VIV for composite risers is rarely involved. Three different risers (one steel riser and two composite risers were compared for their VIV characteristics. The effects of 2D and 3D models and fluid–structure interaction (FSI were considered. The models of composite risers are established by effective modulus method (EMM and layered-structure method (LSM. It is found that 2D model are only suitable for ideal condition, while, for real situation, 3D model with FSI has to be considered. The results show that the displacements of the FRP composite risers are significantly larger than those of the steel riser, while the stresses are reversed. In addition, the distributions of the displacements and stresses depend on the geometries, material properties, top-tension force, constraints, etc. In addition, it is obvious that EMM are suitable to study the global working condition while LSM can be utilized to obtain the results in every single composite layer.

  12. Response prediction of long flexible risers subject to forced harmonic vibration

    OpenAIRE

    Riveros, Carlos Alberto; Utsunomiya, Tomoaki; Maeda, Katsuya; Itoh, Kazuaki

    2010-01-01

    Several research efforts have been directed toward the development of models for response prediction of flexible risers. The main difficulties arise from the fact that the dynamic response of flexible risers involves highly nonlinear behavior and a self-regulated process. This article presents a quasi-steady approach for response prediction of oscillating flexible risers. Amplitude-dependent lift coefficients are considered, as is an increased mean drag coefficient model during synchronizatio...

  13. Dalia integrated production bundle (IPB): an innovative riser solution for deep water fields

    Energy Technology Data Exchange (ETDEWEB)

    Reals, Th Boscals de; Gloaguen, M.; Roche, F. [Total E and P (Angola); Marion, A.; Poincheval, A. [Technip, Paris (France)

    2008-07-01

    The Dalia field is located 210 km north west of Luanda (Angola), about 140 km from shore in 1400 meter water-depth. It was the second major discovery out of 15 made in the block 17 operated by Total. The Dalia Umbilical, Flow lines and Risers EPCI Contract was awarded in 2003. The sea-line network to connect and control the 71 wells and 9 manifolds consist of the following: 40 km of insulated pipe in pipe (12 inches into 17 inches) production flow lines; 45 km of 12 inches water and gas injection lines; 6 off 1.7 km flexible water and gas injection risers; 8 off 1.65 km flexible Integrated Production Bundle (IPB) risers; 75 km of control umbilicals. The flow assurance and associated insulation requirement of the production transport system was one of the main challenges of the project. With a crude temperature of 45 deg C at the wellhead and the required minimum temperature of 35 deg C on arrival at the FPSO, this problem was complex. Understanding that, due to the Joule Thompson effect of the riser gas lift, a 'built in' loss of about 5 deg C is induced and together with further losses through the sub sea pipelines, some up to 6 km long, the agreed solution was 'pipe in pipe' for the production flow lines. The innovative flexible IPB riser, incorporating gas lift and heating to keep the fluid temperature above hydrate formation zone, was the selected riser solution. The IPB is new technology for deep water, developed by Technip for Dalia, and consists of a 12 inches nominal central flexible, surrounded by layers of heat tracing cables, small bore gas lift lines, optical fibres and many insulation layers with an Overall Heat Transfer Coefficient of approximately 3,4 W/m{sup 2}K. After an earlier research and development programme, a further extensive qualification programme was conducted during the course of the project, culminating with the deep water testing phase offshore Brazil. The IPB was then approved for fabrication and installation

  14. Pressured drilling riser design for drilling in ultra deep water with surface bop

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J.; Morrison, D.; Efthymiou, M.; Lo, K.H. [Shell Global Solutions, 78 - Velizy Villacoublay (France); Magne, E.; Leach, C. [Shell Internationale Exploration and Production (Netherlands)

    2002-12-01

    In conventional drilling with a semi-submersible rig valuable rig time is used to run and retrieve the BOP and its accessories on the seabed, and this time increases with water depth. Furthermore, use of the conventional sub-sea BOP requires a large-diameter riser, which requires substantial rig storage and deck load capacity prior to installation. It also requires high riser-tensioning capacity or additional buoyancy. Thus as the water depth increases, it leads to a need for heavy duty 4. and 5. generation rigs with escalation in costs. The high cost of deep-water drill rigs is leading to the development of Surface BOP technology. In this development, the BOP is placed above sea level and the riser is simply a continuation of the casing (typical diameter 13-3/8''). This eliminates the need for a heavy 21'' riser and for running the BOP to the sea bed and retrieving it. Moreover, the reduced tension requirement for the smaller riser extends the water depth capability of 3. generation drilling semi-submersibles, enabling them to drill in deeper waters. A critical success factor for this development is the ability to design the riser/casing to withstand high internal pressures due to well kicks, in addition to environmental loads, and to restrict vessel offsets within certain limits so as not to overload the riser under the prevailing weather conditions. This paper addresses the design considerations of a pressured drilling riser that can be used with a surface BOP in deep-water. Key design issues that are sensitive to ultra-deep-water applications are discussed. The technical aspects of using (disposable) standard casing with threaded connector for the drilling riser are discussed, with a particular emphasis on the connector fatigue-testing program to quantify the stress concentration factor for fatigue design. Emerging composite material offers some alternatives to the steel riser when drilling in ultra-deep water Design issues related to the

  15. A case study on riser analysis of a drilling riser in deep waters; Estudo de caso: analises estruturais e hidrodinamicas de um riser de perfuracao em aguas profundas

    Energy Technology Data Exchange (ETDEWEB)

    Roveri, Francisco E.; Pestana, Rafael G. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    2008-07-01

    This paper presents a set of structural and hydrodynamic analyses of a connected marine riser, in 1900 meter water depth. Operating windows are determined for one year return period environmental conditions and for a set of drilling fluid weight density values. Parametric analyses are carried out to study the riser response sensitivity to variations in environmental conditions, drilling fluid weight density, upper and lower flex joint rotational stiffness and vessel motion phase angles. Current, drilling fluid weight density and vessel motion phase angle changes affect significantly the system response, whereas the response is not significantly affected by changes in wave height, wave period and flex joint rotational stiffness. (author)

  16. Development of a 14-inch ID High-Pressure Hybrid Riser for SBOP Drilling Développement d’un riser hybride 14”ID haute pression pour le forage SBOP

    Directory of Open Access Journals (Sweden)

    Persent E.

    2009-11-01

    Full Text Available This paper discusses the development of a 14-inch ID high-pressure hybrid riser (10 000 psi for surface BOP drilling in ultra-deep water (10 000 ft. The high-pressure hybrid riser system is obtained by adapting and combining two existing technologies, previously developed by the IFP for other applications: – the Clip connector, a double breech-block type connector to provide a quick and safe connection for riser joints; – hybrid pipe technology, a steel pipe hoop-wound with tapes of carbon fibers impregnated with polyamide thermoplastic resin. IFP has developed a new 14-inch ID HP Clip connector for the hybrid riser application. The connector is capable of withstanding a 2.8 million pound tension and a 10 000 psi operating pressure. In addition, a 16-inch nominal OD hybrid riser pipe has been designed to replace the steel riser pipe with a thinnerwalled hoop-wound steel pipe. The significant weight savings that can be achieved with the hybrid riser pipe make it possible to design an effective riser architecture to withstand the high pressure and deep water requirements. Pursuant to design studies, a 14-inch ID prototype assembly consisting of two hybrid riser pipe sections with a high-pressure Clip connector was manufactured. A test program, including burst and collapse tests as well as cyclic fatigue testing, was formulated and carried out to qualify the performance of the Clip connector and hybrid riser pipe system. Completion of hybrid pipe additional fatigue testing and realization of a scale-one field testing of the hybrid riser are considered as the next steps of the project. To date, the main test results (burst, collapse, fatigue resistance confirm that the Clip connector and the hybrid pipe technologies are well suited for ultra-deep sea drilling with a surface BOP. However, the fatigue resistance of hybrid riser pipes still needs to be better characterized. Cet article présente le développement d’un riser hybride 14”ID haute

  17. CFD Study of Industrial FCC Risers: The Effect of Outlet Configurations on Hydrodynamics and Reactions

    Directory of Open Access Journals (Sweden)

    Gabriela C. Lopes

    2012-01-01

    Full Text Available Fluid catalytic cracking (FCC riser reactors have complex hydrodynamics, which depend not only on operating conditions, feedstock quality, and catalyst particles characteristics, but also on the geometric configurations of the reactor. This paper presents a numerical study of the influence of different riser outlet designs on the dynamic of the flow and reactor efficiency. A three-dimensional, three-phase flow model and a four-lump kinetic scheme were used to predict the performance of the reactor. The phenomenon of vaporization of the liquid oil droplets was also analyzed. Results showed that small changes in the outlet configuration had a significant effect on the flow patterns and consequently, on the reaction yields.

  18. Riser equipment decontamination engineering task plan

    International Nuclear Information System (INIS)

    BOGER, R.M.

    1999-01-01

    On October 15, 1998, two Characterization Project Operations (CPO) employees were found to have contaminated clothing. An operator had 300,000-dpm/100cm2 beta/gamma, no alpha, contamination on his coat sleeve and a Radiation Control Technician (RCT) had 10,000 dpm/100cm2 beta/gamma, no alpha, on his shirt sleeve. The CPO swing shift crew was working in TX tank farm, performing sampling activities at 241-TX-113. TX tank farm is a ''clean farm'' and does not require anti-contamination clothing for entry. The CPO personnel were dressed in normal work clothes. An operator and an RCT were performing a pre-job survey that involved removing bagging around the riser equipment. When the RCT saw that the contamination readings from smear samples of the riser equipment were greater than expected, the job was suspended. Crew members were then directed to areas of lower background radiation for personnel surveys. During personnel surveys, reportable contamination was found on the coat sleeve of the operator who had been involved in the pre-job survey and on the shirt sleeve of the RCT who had been involved in the pre-job survey. No other personnel were found to be contaminated. Because of this off normal event Characterization Engineering was given the following corrective action: Examine the process methodology used for core sampling operations to determine practicality and potential long-term advantages of reducing personnel contact with contaminated equipment. This Engineering Task Plan ensures that LMHC 1998a, Corrective Action No.7 is completely addressed by Characterization Engineering. The deliverable is an Engineering Study that evaluates decontamination of riser equipment components and considers additional engineered features to reduce potential exposure to workers operating the riser equipment. This engineering study shall also address any released design features that have failed to be implemented

  19. Development and characterization of composite materials for production of composite risers by filament winding

    Energy Technology Data Exchange (ETDEWEB)

    Sobrinho, L.L.; Bastian, F.L. [Federal University of Rio de Janeiro, RJ (Brazil). Dept. of Metallurgical and Materials Engineering], e-mail: ledjane@metalmat.ufrj.br; Calado, V.M.A. [Federal University of Rio de Janeiro, RJ (Brazil). Escola de Quimica

    2008-07-01

    Industry has been challenged to provide riser systems which are more cost effective and which can fill the technology gaps with respect to water depth, riser diameter and high temperatures left open by flexible, steel catenary risers (SCRs) and hybrid risers. Composite materials present advantages over conventional steel risers because composite materials are lighter, more fatigue and corrosion resistant, better thermal insulators and can be designed for improving the structural and mechanical response. Besides, composite materials present some attractive attributes for the offshore service, such as: high specific strength and stiffness. This paper focuses on the development and characterization of a polymer matrix (epoxy) and of material composite (epoxy/fiber glass), which will be used in a development for composites risers by the filament winding process (wet winding). (author)

  20. Numerical Modeling and Mechanical Analysis of Flexible Risers

    OpenAIRE

    Li, J. Y.; Qiu, Z. X.; Ju, J. S.

    2015-01-01

    ABAQUS is used to create a detailed finite element model for a 10-layer unbonded flexible riser to simulate the riser’s mechanical behavior under three load conditions: tension force and internal and external pressure. It presents a technique to create detailed finite element model and to analyze flexible risers. In FEM model, all layers are modeled separately with contact interfaces; interaction between steel trips in certain layers has been considered as well. FEM model considering contact ...

  1. Simplified Model for Evaluation of VIV-induced Fatigue Damage of Deepwater Marine Risers

    Institute of Scientific and Technical Information of China (English)

    XUE Hong-xiang; TANG Wen-yong; ZHANG Sheng-kun

    2009-01-01

    A simplified empirical model for fatigue analysis of deepwater marine risers due to vortex-induced vibration (VIV) in non-uniform current is presented. A simplified modal vibration equation is employed according to the characteristics of deepwater top tensioned risers. The response amplitude of each mode is determined by a balance between the energy feeding into the riser over the lock-in regions and the energy dissipated by the fluid damping over the remainder based on the data from self-excited oscillation and forced oscillation experiments of rigid cylinders. Multi-modal VIV fatigue loading is obtained by the square root of the sum of squares approach.Compared with previous works, this model can take fully account of the main intrinsic natures of VIV for low mass ratio structures on lock-in regions, added mass and nonlinear fluid damping. In addition, a closed form solution of fatigue damage is presented for the case of a riser with uniform mass and cross-section oscillating in a uniform flow. Fatigue analysis of a typical deepwater riser operating in Gulf of Mexico and West Africa shows that the current velocity profiles affect the riser's fatigue life significantly and the most dangerous locations of the riser are also pointed out.

  2. A state space approach for the eigenvalue problem of marine risers

    KAUST Repository

    Alfosail, Feras; Nayfeh, Ali H.; Younis, Mohammad I.

    2017-01-01

    A numerical state-space approach is proposed to examine the natural frequencies and critical buckling limits of marine risers. A large axial tension in the riser model causes numerical limitations. These limitations are overcome by using

  3. Girassol, Riser Towers for ultra deep water

    Energy Technology Data Exchange (ETDEWEB)

    Rougier, Regis

    1999-07-01

    This is a brief presentation of the technical concept developed by ALTO MAR GIRASSOL (AMG) for the Girassol umbilical and flowlines system. In 1998 AMG was awarded a contract by Elf Exploration Angola for the engineering, procurement, construction and installation (EPCI) of the umbilical and flowline system. The technical concept is based around the use of sealine bundles and self-supporting hybrid riser towers which carry the production, water injection, gas injection, gas lift and service lines. The items discussed are: (1) selected field layout, (2) seabed flowlines, hybrid riser system, umbilicals, export lines, installation plan and overall project schedule.

  4. Identifying and evaluating high risk areas and challenges on marine drilling riser system in relation to deepwater problems

    OpenAIRE

    Iversen, Alexander

    2012-01-01

    Master's thesis in Offshore technology The main concerns during drilling operations are riser integrity and maintaining well control. This thesis has mainly been focusing on the problems and challenges faced with the marine riser system to illuminate high risk areas related to riser integrity. A marine riser system consists generally of four main elements; the upper marine riser package, riser joints, lower marine riser package, and the blowout preventer, each playing an important par...

  5. Flexible riser global analysis for very shallow water

    OpenAIRE

    Karegar, Sadjad

    2013-01-01

    Master's thesis in Offshore technology Flexible risers are widely used for a range of water depths and can accommodate large floater motions when using a buoyant system. A wide range of buoyancy solutions have been developed for very shallow water (e.g. 30-50 m), shallow water (e.g. 90-110 m) and semi-deep water (e.g. 300-400 m) and in the ranges between these depths. Flexible risers can have different configurations. These different solutions have different characteristics which influe...

  6. Damage localization of marine risers using time series of vibration signals

    Science.gov (United States)

    Liu, Hao; Yang, Hezhen; Liu, Fushun

    2014-10-01

    Based on dynamic response signals a damage detection algorithm is developed for marine risers. Damage detection methods based on numerous modal properties have encountered issues in the researches in offshore oil community. For example, significant increase in structure mass due to marine plant/animal growth and changes in modal properties by equipment noise are not the result of damage for riser structures. In an attempt to eliminate the need to determine modal parameters, a data-based method is developed. The implementation of the method requires that vibration data are first standardized to remove the influence of different loading conditions and the autoregressive moving average (ARMA) model is used to fit vibration response signals. In addition, a damage feature factor is introduced based on the autoregressive (AR) parameters. After that, the Euclidean distance between ARMA models is subtracted as a damage indicator for damage detection and localization and a top tensioned riser simulation model with different damage scenarios is analyzed using the proposed method with dynamic acceleration responses of a marine riser as sensor data. Finally, the influence of measured noise is analyzed. According to the damage localization results, the proposed method provides accurate damage locations of risers and is robust to overcome noise effect.

  7. Monitoring system of depressurization valves of migrated gas in annular space of flexible risers

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, Luiz A.; Santos, Joilson M.; Carvalho, Antonio L.; Loureiro, Patricia [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2005-07-01

    PETROBRAS Research and Development Center - CENPES developed an automatic system for monitoring pressure of annular space due to permeation of gas in flexible risers to inspect continuously integrity of such lines. To help maintaining physical integrity of flexible risers, two PSV's are installed to end fittings on top of riser, so that operation of any valve grants the maximum admissible gas pressure within the riser annular space, as overpressure might cause damages to external polymeric layer of flexible riser. Due to the fact that there is no mechanism allowing operation to verify correct PSV performance and frequency of valve's closings and openings, we felt to be necessary the development and implement an automatic instrumented system, integrated to platform's automation and control infrastructure. The objective of this instrumentation is to monitor and register pressure of annular space in flexible riser, as well as XV's depressurization frequency. Having such information registered and monitored, can infer some riser structural conditions, anticipating repairs and preventive maintenance. In this paper we present developed system details including instruments required, application, operation of associated screens that are used in the ECOS, with events, alarms and industrial automation services required (Application development and system integration). (author)

  8. Riser equipment decontamination engineering task plan; TOPICAL

    International Nuclear Information System (INIS)

    BOGER, R.M.

    1999-01-01

    On October 15, 1998, two Characterization Project Operations (CPO) employees were found to have contaminated clothing. An operator had 300,000-dpm/100cm2 beta/gamma, no alpha, contamination on his coat sleeve and a Radiation Control Technician (RCT) had 10,000 dpm/100cm2 beta/gamma, no alpha, on his shirt sleeve. The CPO swing shift crew was working in TX tank farm, performing sampling activities at 241-TX-113. TX tank farm is a ''clean farm'' and does not require anti-contamination clothing for entry. The CPO personnel were dressed in normal work clothes. An operator and an RCT were performing a pre-job survey that involved removing bagging around the riser equipment. When the RCT saw that the contamination readings from smear samples of the riser equipment were greater than expected, the job was suspended. Crew members were then directed to areas of lower background radiation for personnel surveys. During personnel surveys, reportable contamination was found on the coat sleeve of the operator who had been involved in the pre-job survey and on the shirt sleeve of the RCT who had been involved in the pre-job survey. No other personnel were found to be contaminated. Because of this off normal event Characterization Engineering was given the following corrective action: Examine the process methodology used for core sampling operations to determine practicality and potential long-term advantages of reducing personnel contact with contaminated equipment. This Engineering Task Plan ensures that LMHC 1998a, Corrective Action No.7 is completely addressed by Characterization Engineering. The deliverable is an Engineering Study that evaluates decontamination of riser equipment components and considers additional engineered features to reduce potential exposure to workers operating the riser equipment. This engineering study shall also address any released design features that have failed to be implemented

  9. An efficient structural finite element for inextensible flexible risers

    Science.gov (United States)

    Papathanasiou, T. K.; Markolefas, S.; Khazaeinejad, P.; Bahai, H.

    2017-12-01

    A core part of all numerical models used for flexible riser analysis is the structural component representing the main body of the riser as a slender beam. Loads acting on this structural element are self-weight, buoyant and hydrodynamic forces, internal pressure and others. A structural finite element for an inextensible riser with a point-wise enforcement of the inextensibility constrain is presented. In particular, the inextensibility constraint is applied only at the nodes of the meshed arc length parameter. Among the virtues of the proposed approach is the flexibility in the application of boundary conditions and the easy incorporation of dissipative forces. Several attributes of the proposed finite element scheme are analysed and computation times for the solution of some simplified examples are discussed. Future developments aim at the appropriate implementation of material and geometric parameters for the beam model, i.e. flexural and torsional rigidity.

  10. OTEC riser cable model and prototype testing

    Science.gov (United States)

    Kurt, J. P.; Schultz, J. A.; Roblee, L. H. S.

    1981-12-01

    Two different OTEC riser cables have been developed to span the distance between a floating OTEC power plant and the ocean floor. The major design concerns for a riser cable in the dynamic OTEC environment are fatigue, corrosion, and electrical/mechanical aging of the cable components. The basic properties of the cable materials were studied through tests on model cables and on samples of cable materials. Full-scale prototype cables were manufactured and were tested to measure their electrical and mechanical properties and performance. The full-scale testing was culminated by the electrical/mechanical fatigue test, which exposes full-scale cables to simultaneous tension, bending and electrical loads, all in a natural seawater environment.

  11. Engineering Task Plan for simulated riser installation by use of rotary drilling

    International Nuclear Information System (INIS)

    Barnes, G.A.

    1995-12-01

    This task is being performed to demonstrate the feasibility of the best riser installation alternative identified in the Engineering Study. This Engineering Task Plan (ETP) will be the WHC project management plan for the riser installation demonstration activities

  12. Magnetic non-destructive evaluation of ruptures of tensile armor in oil risers

    International Nuclear Information System (INIS)

    Pérez-Benitez, J A; Padovese, L R

    2012-01-01

    Risers are flexible multilayered pipes formed by an inner flexible metal structure surrounded by polymer layers and spiral wound steel ligaments, also known as armor wires. Since these risers are used to link subsea pipelines to floating oil and gas production installations, and their failure could produce catastrophic consequences, some methods have been proposed to monitor the armor integrity. However, until now there is no practical method that allows the automatic non-destructive detection of individual armor wire rupture. In this work we show a method using magnetic Barkhausen noise that has shown high efficiency in the detection of armor wire rupture. The results are examined under the cyclic and static load conditions of the riser. This work also analyzes the theory behind the singular dependence of the magnetic Barkhausen noise on the applied tension in riser armor wires. (paper)

  13. An analytic solution of the static problem of inclined risers conveying fluid

    KAUST Repository

    Alfosail, Feras; Nayfeh, Ali H.; Younis, Mohammad I.

    2016-01-01

    We use the method of matched asymptotic expansion to develop an analytic solution to the static problem of clamped–clamped inclined risers conveying fluid. The inclined riser is modeled as an Euler–Bernoulli beam taking into account its self

  14. Most recent developments for monitoring and controlling the annulus conditions of Marlim-Sul flexible risers

    Energy Technology Data Exchange (ETDEWEB)

    Rabelo, Alexandre S.; Motta, Antonio; Romero, Antonio; Nunes, Joao P.; Zaganelli Junior, Jose L.; Brack, Marcelo [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The main objective of this paper is to present the recent developments for monitoring and controlling the annulus conditions of flexible risers. PETROBRAS has been monitoring the pressure of permeated gas in the annulus region of some risers in order to infer the eventual occurrence of non-conformities as damage on the riser external sheath, for example. Such occurrence would affect the permeated gas flow pattern, the gas pressurization period and the relief valve opening frequencies. Furthermore, the mentioned occurrence would increase the susceptibility of the steel armors to experience the potential failure mechanism of corrosion. In PETROBRAS, the current monitoring method is characterized by visual and periodic manometer readings from a manometer set installed near each riser end-fitting. The data is recorded in a daily report and analyzed by personnel onshore, who are in charge of comparing data and requesting relief valve's actuation, whenever necessary. The paper illustrates Marlim-Sul Asset experience on monitoring and data processing to control the annulus conditions of flexible risers during operation. It presents the in-house developed methodology to data management and processing. This methodology is based on a daily analysis of the permeated gas data worksheet. Some examples are given to illustrate it. The paper also summarizes current developments, in progress, in order to improve riser integrity management. The first development is being done to implement, in the future, automatic data acquisition and control systems. The purpose of automating this process is to improve methods and techniques for data acquisition, transmission and processing. The second development focuses on applications in which riser top end-fittings are submerged. In this particular scenario, a special system - with a quick connection sub sea device - is under development to allow the connection, by divers, after the riser pull-in, of the riser annulus to the platform gas

  15. Tools for in service monitoring and testing of riser to prevent failure and extend service life

    Energy Technology Data Exchange (ETDEWEB)

    Ward, Haakon; Bondevik, Jon Olav; Skjerve, Haavard; Tveit, Oeyvind [SeaFlex AS, Asker (Norway)

    2005-07-01

    Exploration and development of new oil and gas fields is heavily dependant on use of flexible pipes and many field developments would not have been possible without them. The number of flexible risers in service is constantly increasing since relatively few offshore projects have reached the estimated operational life and the operational lifetime of several fields in-service has been extended due to new and improved technology. Many risers have been in service over a large number of years. Some risers have been operated under demanding conditions such as severe dynamic loads, high pressure and temperatures. One may in some cases find that risers actually have shorter service life than estimated in the design phase due to the severe operational conditions. In order to extend the use of the riser, some risers may have to be modified and re-terminated and prepared for a new and less demanding application. In order to operate risers safely, it is important to re-assess the fatigue life in order to prevent potential riser failure. The operator should implement methods and tools for in-service monitoring and testing. This paper addresses efficient and reliable methods and tools for monitoring of critical operational parameters as well as in-service riser testing. A brief description of structural failure modes will also be given in order to understand how to interpret test results in view of potential failure modes. (author)

  16. Oscillation of a rigid catenary riser due to the internal two-phase flow

    Energy Technology Data Exchange (ETDEWEB)

    Bordalo, Sergio N.; Morooka, Celso K.; Cavalcante, Cesar C.P. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Matt, Cyntia G.C.; Franciss, Ricardo [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    2008-07-01

    Production of petroleum reservoirs from deep and ultra-deep waters is of paramount importance in Brazil, and several researches are necessary to develop appropriated equipment and risers for those operational conditions. Risers are suspended pipes used to transport the petroleum fluids between the seabed and the floating production unit. The structural flexibility of riser's lines is conferred by its length when compared with the diameter, characterizing it as a slender body. The risers are submitted to large static and dynamic loads originated from its own weight, waves, currents, platform motions and the internal flow. These loadings may threaten, by fatigue, the structural integrity of the system, compromising its useful life, and so they must be considered in the riser's project. There is a large amount of knowledge in the literature about the effects of external loadings on these systems, but the effect of the internal flow remains vastly unexplored. The variation of the flow mass and momentum inside the riser causes a dynamic loading on this system, originating an oscillatory motion. Furthermore, the gas-liquid two-phase flow may assume several flow patterns (bubble, slug, intermittent or annular), each one possessing completely different characteristics. In this work, the influence of the internal flow on the oscillatory motion (whipping motion) of catenary risers is analyzed. To provide a better understanding of this physical phenomenon, a scaled apparatus was designed and built. The material used to manufacture the riser's model was a flexible silicone tube, and air and water were used to simulate the two-phase flow. The instrumentation used to measure the fluids flow rates and the sustaining force at the top of the model was installed in the apparatus. A video acquisition system was used to determine the displacements, and frequency spectrum, of color targets positioned throughout the model, under several flow conditions. The flow patterns

  17. Reliable Radiographic Inspection of Flexible Risers for the Oil Industry

    Science.gov (United States)

    Almeida, Rômulo M.; Rebello, Joao Marcos A.; Vaz, Murilo A.

    2010-02-01

    Flexible risers are composite tubular structures manufactured by the concentric assemblage of cylindrical polymeric and helically wound metallic layers employed to convey pressurized fluids such as oil, gas and water in the ocean environment. The metallic layers account for the flexible risers' structural strength and are dimensioned according to the static and dynamic loads. They are usually installed in a free hanging catenary configuration and are subjected to the direct action of waves and marine currents and wave induced motions from the oil production platform. The fatigue rupture of wire armours in the end fitting or within the riser segment protected by the bend stiffener is an object of major concern. Integrity models have been developed, however inspection techniques are mandatory to ensure that failure is detected. Gammagraphy has been used as a common inspection technique in all regions of the flexible riser, mainly with the single wall-single view method. On the other side, there is not any qualified radiographic procedure to this kind of structure. Radiographic simulation was adopted and its validation with actual gammagraphies and establishment of radiographic parameters to complex radiation geometries were done. Results show the viability of the radiographic inspection analyzing the armour wires' rupture and the displacement between wires.

  18. RELIABLE RADIOGRAPHIC INSPECTION OF FLEXIBLE RISERS FOR THE OIL INDUSTRY

    International Nuclear Information System (INIS)

    Almeida, Romulo M.; Rebello, Joao Marcos A.; Vaz, Murilo A.

    2010-01-01

    Flexible risers are composite tubular structures manufactured by the concentric assemblage of cylindrical polymeric and helically wound metallic layers employed to convey pressurized fluids such as oil, gas and water in the ocean environment. The metallic layers account for the flexible risers' structural strength and are dimensioned according to the static and dynamic loads. They are usually installed in a free hanging catenary configuration and are subjected to the direct action of waves and marine currents and wave induced motions from the oil production platform. The fatigue rupture of wire armours in the end fitting or within the riser segment protected by the bend stiffener is an object of major concern. Integrity models have been developed, however inspection techniques are mandatory to ensure that failure is detected. Gammagraphy has been used as a common inspection technique in all regions of the flexible riser, mainly with the single wall-single view method. On the other side, there is not any qualified radiographic procedure to this kind of structure. Radiographic simulation was adopted and its validation with actual gammagraphies and establishment of radiographic parameters to complex radiation geometries were done. Results show the viability of the radiographic inspection analyzing the armour wires' rupture and the displacement between wires.

  19. Multidimensional analysis of developing two-phase flows in an ESBWR chimney with and without riser channels

    International Nuclear Information System (INIS)

    Murakawa, H.; Antal, S.P.; Lahey, R T.

    2008-01-01

    The object of this work was to simulate developing multidimensional velocity and void fraction distributions in bubbly and churn turbulent two-phase flows. An advanced Computational Multiphase Fluid Dynamics (CMFD) code, NPHASE, was used to perform three-dimensional, multi-field simulations of the developing phasic velocity and phase distributions in vertical adiabatic conduits. The NPHASE code employed a multi-field two-fluid model, in which, for churn turbulent flow, the vapor phase was divided into small and large, cap bubble fields. In addition, state-of-the-art interfacial area density and field-to-field mass transfer models were used for both the small and large, cap bubbles. In particular, the bubble breakup and coalescence processes were quantified using a two-group interfacial area density transport equation. This allowed the CMFD simulation of developing churn turbulent flows in an ESBWR with and without vertical riser channels in the chimney region above the core. Based on these simulations it was concluded that riser channels have little adverse effect on the induced natural circulation flow through the core and the stability characteristics of an ESBWR. (authors)

  20. Development and characterization of composite materials for production of composite risers by filament winding

    Directory of Open Access Journals (Sweden)

    Ledjane Lima Sobrinho

    2011-09-01

    Full Text Available Industry has been challenged to provide riser systems which are more cost effective and which can fill the technology gaps with respect to water depth, riser diameter and high temperatures left open by flexibles, steel catenary risers (SCRs and hybrid risers. Composite materials present advantages over conventional steel risers because composite materials are lighter, more fatigue and corrosion resistant, better thermal insulators and can be designed for improving the structural and mechanical response. This paper contains a study of the toughening mechanism of an epoxy resin under rubber addition by means of fractographic analysis and its relation with the fracture process and increase of strength of a composite riser employing this polymeric matrix. Initially, an epoxy resin system was toughened by rubber CTBN addition (10 wt. (% as a way of improving the flexibility of future risers. Mechanical and thermal analyses were carried out for characterizing the polymeric systems. Later, composite tubes were prepared and mechanically characterized. The influence of matrix toughening on the mechanical behavior of the tubes was also studied. Split-disk tests were used to determine the hoop tensile strength of these specimens. The results indicate that the matrix plays an important role in composite fracture processes. The adding rubber to the polymeric matrix promoted a simultaneous increase of stress and elongation at fracture of the tubes manufactured herein, which is not often reported. These results, probably, is function of better adhesion between fibers and polymeric matrix observed in the CTBN-modified composite rings, which was evidenced in the fractografic analysis by SEM after the split-disk tests.

  1. Validation of mathematical models to describe fluid dynamics of a cold riser by gamma ray attenuation; Validacao de modelos matematicos para descrever a fluidodinamica de um riser utilizando atenuacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Ana Cristina Bezerra Azedo de

    2004-12-15

    The fluid dynamic behavior of a riser in a cold type FCC model was investigated by means of catalyst concentration distribution measured with gamma attenuation and simulated with a mathematical model. In the riser of the cold model, MEF, 0,032 m in diameter, 2,30 m in length the fluidized bed, whose components are air and FCC catalyst, circulates. The MEF is operated by automatic control and instruments for measuring fluid dynamic variables. An axial catalyst concentration distribution was measured using an Am-241 gamma source and a NaI detector coupled to a multichannel provided with a software for data acquisition and evaluation. The MEF was adapted for a fluid dynamic model validation which describes the flow in the riser, for example, by introducing an injector for controlling the solid flow in circulation. Mathematical models were selected from literature, analyzed and tested to simulate the fluid dynamic of the riser. A methodology for validating fluid dynamic models was studied and implemented. The stages of the work were developed according to the validation methodology, such as data planning experiments, study of the equations which describe the fluidodynamic, computational solvers application and comparison with experimental data. Operational sequences were carried out keeping the MEF conditions for measuring catalyst concentration and simultaneously measuring the fluid dynamic variables, velocity of the components and pressure drop in the riser. Following this, simulated and experimental values were compared and statistical data treatment done, aiming at the required precision to validate the fluid dynamic model. The comparison tests between experimental and simulated data were carried out under validation criteria. The fluid dynamic behavior of the riser was analyzed and the results and the agreement with literature were discussed. The adopt model was validated under the MEF operational conditions, for a 3 to 6 m/s gas velocity in the riser and a slip

  2. Three-Dimensional Dynamics of a Flexible Marine Riser Undergoing Large Elastic Deformations

    International Nuclear Information System (INIS)

    Raman-Nair, W.; Baddour, R.E.

    2003-01-01

    The equations of the three dimensional motion of a marine riser undergoing large elastic deformations are formulated using Kane's formalism. The riser is modeled using lumped masses connected by extensional and rotational springs including structural damping. Surface waves are described by Stokes? second-order wave theory. Fluid-structure coupling is achieved by application of the hydrodynamic loads via Morison's equation and added-mass coefficients using the instantaneous relative velocities and accelerations between the fluid field and the riser segments. In the same way, a model for incorporating the effects of vortex-induced lift forces is included. The effect of internal flow is included in the model. The detailed algorithm is presented and the equations are solved using a robust implementation of the Runge-Kutta method provided in MATLAB. The mathematical model and associated algorithm are validated by comparing the steady-state equilibrium configuration of the riser with special cases of an elastic catenary mooring line and large deflection statics of a cantilever beam. The results of sample simulations are presented

  3. An optical sensor for the detection of leaks from subsea pipelines and risers

    International Nuclear Information System (INIS)

    McStay, D; Kerlin, J; Acheson, R

    2007-01-01

    An optical sensor for the rapid detection of detect leaks of oil, hydraulic fluids or leak detection chemicals from underwater pipelines and risers is reported. The sensor is designed to be deployed on ROVs or AUVs for the rapid survey of underwater pipelines and risers. The system employs ultra-bright LEDs to project a sensing light beam into the water to allow real time detection of ppm concentration plumes of material leaking from pipelines or riser in real time. Typically the system is deployed on an ROV which inspects a pipeline at a height of 2-3m

  4. Singing mitigation in an export riser via liquid injection: a field case study

    NARCIS (Netherlands)

    Belfroid, S.P.C.; Korst, H.J.C.; Beek, P.J.G. van; Lunde, K.; Eidsvik, I.G.; Hansen, F.; Olsen, B.

    2014-01-01

    Flexible Risers are prone to the generation of high amplitude tonal noise, i.e. a so-called singing riser. Recently, severe vibrations and high noise levels were encountered on the turret of an FPSO in the Norwegian Sea, resulting in significantly reduced production. The vibrations could be

  5. The Sleipner riser platform experience

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The article discusses briefly the Norwegian Sleipner riser project. The project has provided new insight on how to handle smaller development projects in a time saving and cost effective way. Through active cooperation between the prime contractors, the total project time, which included engineering, fabrication ready to tow, was slashed to a record 11 months. Normally, such a project would take a couple of years to complete. 1 fig

  6. 3D simulation of the catalyst density radial distribution in a riser of the FCC unit; Simulacao 3D da distribuicao radial de densidade do catalisador num riser de uma unidade de FCC

    Energy Technology Data Exchange (ETDEWEB)

    Apolonio, Adelia M.; Santos, Valdemir A. dos; Finkler, Christine L.L. [Universidade Catolica de Pernambuco (UNICAP), Recife, PE (Brazil); Dantas, Carlos C. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear

    2008-07-01

    Local variations in the catalyst/vacuum gas oils mixing can lead to low conversions in some parts of a fluid cracking catalytic riser, while in other parts, high conversions will produce undesirable fuel gas and coke quantities. Knowledge of the apparent solid concentration in a cross-section of the riser is then essential. A computational program to generate tri dimensional graphics and level curves of the radial catalyst density in FCC risers was elaborated. The algorithm is based on determinations of the polynomial coefficients with aid of least square method and was tested with literature data, obtained by applications of nuclear technique of gamma radiation attenuation. The simulation results showed convergence with the experimental data. The precision of the mapping depends on the number of measurements and promote better conditions of diagnostic of the distribution catalyst type in the riser. (author)

  7. Inspection and monitoring techniques for un-bonded flexible risers and pipelines

    OpenAIRE

    Simonsen, Anders

    2014-01-01

    Master's thesis in Offshore technology Un-bonded flexible pipelines and risers are an alternative to conventional rigid steel pipes. The use of flexible pipes has enabled development of several offshore fields that seemed unfeasible with the use of rigid pipes due to extensive seabed preparation and large dynamic motions. The lack of knowledge and integrity management tools for flexible pipes is a limiting factor and cause pipelines and risers to be replaced before their service life has ...

  8. Flow Mapping in a Gas-Solid Riser via Computer Automated Radioactive Particle Tracking (CARPT)

    Energy Technology Data Exchange (ETDEWEB)

    Muthanna Al-Dahhan; Milorad P. Dudukovic; Satish Bhusarapu; Timothy J. O' hern; Steven Trujillo; Michael R. Prairie

    2005-06-04

    Statement of the Problem: Developing and disseminating a general and experimentally validated model for turbulent multiphase fluid dynamics suitable for engineering design purposes in industrial scale applications of riser reactors and pneumatic conveying, require collecting reliable data on solids trajectories, velocities ? averaged and instantaneous, solids holdup distribution and solids fluxes in the riser as a function of operating conditions. Such data are currently not available on the same system. Multiphase Fluid Dynamics Research Consortium (MFDRC) was established to address these issues on a chosen example of circulating fluidized bed (CFB) reactor, which is widely used in petroleum and chemical industry including coal combustion. This project addresses the problem of lacking reliable data to advance CFB technology. Project Objectives: The objective of this project is to advance the understanding of the solids flow pattern and mixing in a well-developed flow region of a gas-solid riser, operated at different gas flow rates and solids loading using the state-of-the-art non-intrusive measurements. This work creates an insight and reliable database for local solids fluid-dynamic quantities in a pilot-plant scale CFB, which can then be used to validate/develop phenomenological models for the riser. This study also attempts to provide benchmark data for validation of Computational Fluid Dynamic (CFD) codes and their current closures. Technical Approach: Non-Invasive Computer Automated Radioactive Particle Tracking (CARPT) technique provides complete Eulerian solids flow field (time average velocity map and various turbulence parameters such as the Reynolds stresses, turbulent kinetic energy, and eddy diffusivities). It also gives directly the Lagrangian information of solids flow and yields the true solids residence time distribution (RTD). Another radiation based technique, Computed Tomography (CT) yields detailed time averaged local holdup profiles at

  9. An experimental study on the key fretting variables for flexible marine risers

    OpenAIRE

    O’Halloran, S.M.; Harte, A.M.; Shipway, P.H.; Leen, S.B.

    2018-01-01

    This paper presents an experimental investigation into the effects of contact conformity, contact pressure and displacement amplitude on the gross-slip fretting behaviour grease-lubricated cylinder-on-flat contacts in the context of flexible marine riser pressure armour wire, and compares behaviour with that observed in unlubricated conditions. Characterisation of friction and wear is critical to fretting fatigue life prediction in flexible risers since friction directly controls trailing-edg...

  10. Vector form Intrinsic Finite Element Method for the Two-Dimensional Analysis of Marine Risers with Large Deformations

    Science.gov (United States)

    Li, Xiaomin; Guo, Xueli; Guo, Haiyan

    2018-06-01

    Robust numerical models that describe the complex behaviors of risers are needed because these constitute dynamically sensitive systems. This paper presents a simple and efficient algorithm for the nonlinear static and dynamic analyses of marine risers. The proposed approach uses the vector form intrinsic finite element (VFIFE) method, which is based on vector mechanics theory and numerical calculation. In this method, the risers are described by a set of particles directly governed by Newton's second law and are connected by weightless elements that can only resist internal forces. The method does not require the integration of the stiffness matrix, nor does it need iterations to solve the governing equations. Due to these advantages, the method can easily increase or decrease the element and change the boundary conditions, thus representing an innovative concept of solving nonlinear behaviors, such as large deformation and large displacement. To prove the feasibility of the VFIFE method in the analysis of the risers, rigid and flexible risers belonging to two different categories of marine risers, which usually have differences in modeling and solving methods, are employed in the present study. In the analysis, the plane beam element is adopted in the simulation of interaction forces between the particles and the axial force, shear force, and bending moment are also considered. The results are compared with the conventional finite element method (FEM) and those reported in the related literature. The findings revealed that both the rigid and flexible risers could be modeled in a similar unified analysis model and that the VFIFE method is feasible for solving problems related to the complex behaviors of marine risers.

  11. Numerical simulations of the dynamic of steel catenary riser under the influence of VIV-Vortex-Induced Vibration

    Energy Technology Data Exchange (ETDEWEB)

    Tsukada, Raphael I.; Morooka, Celso K. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica; Franciss, Ricardo; Matt, Cyntia G.C. [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2009-07-01

    Hydrocarbon discoveries in ultra deep waters and the recent pre-salt deep carbonate reservoirs along the Brazilian coast demand further technological development in order to exploit these resources. These developments usually require new concepts for offshore sea surface structures and subsea systems for the petroleum and gas production, which means cost effective solutions that provides higher operational safety on drilling and production operations. In this scenario, the effect of the natural phenomenon of Vortex-Induced Vibration (VIV) on risers is one of the concerns for its design due to the tendency of VIV to increase levels of stresses in the riser structure. Therefore the correct prediction of stresses and displacements due to VIV is of great importance for designing riser systems. The present work presents new developments based on previous results for VIV in vertical risers extended to curved risers such as steel catenary risers (SCR). Numerical simulations have been performed in time domain, and experimental results from model tests with a scaled SCR in a towing tank have been used to evaluate the proposed developments. Finally, the conclusions from the analysis of the results bring very promising results. (author)

  12. Hydrodynamics of a natural circulation loop in a scaled-down steam drum-riser-downcomer assembly

    Energy Technology Data Exchange (ETDEWEB)

    Basu, Dipankar N., E-mail: dnbasu@iitg.ernet.in; Patil, N.D.; Bhattacharyya, Souvik; Das, P.K.

    2013-12-15

    Highlights: • Experimental investigation of loop hydrodynamics in a scaled-down simulated AHWR. • Identification of flow regimes and transition analyzing conductance probe signal. • Downcomer flow maximizes with fully developed churn flow and lowest for bubbly flow. • Highest downcomer flow rate is achieved with identical air supply to both risers. • Interaction of varying flow patterns reduces downcomer flow for unequal operation. - Abstract: Complex interactions of different phases, widely varying frictional characteristics of different flow regimes and the involvement of multiple scales of transport make the modelling of a two-phase natural circulation loop (NCL) exceedingly difficult. The knowledge base about the dependency of downcomer flow rate on riser-side flow patterns, particularly for systems with multiple parallel channels is barely developed, necessitating the need for detailed experimentation. The present study focuses on developing a scaled-down test facility relevant to the Advanced Heavy Water Reactor conceived in the atomic energy programme of India to study the hydrodynamics of the NCL using air and water as test fluids. An experimental facility with two risers, one downcomer and a phase-separating drum was fabricated. Conductivity probes and photographic techniques are used to characterize the two phase flow. Normalized voltage signals obtained from the amplified output of conductivity probes and their subsequent analysis through probability distribution function reveal the presence of different two-phase flow patterns in the riser tubes. With the increase in air supply per riser void fraction in the two-phase mixture increases and gradually flow patterns transform from bubbly to fully developed annular through slug, churn and dispersed annular flow regimes. Downcomer flow rate increases rapidly with air supply till a maximum and then starts decreasing due to enhanced frictional forces. However, the maximum value of downcomer water

  13. Recreating Riser Slugging Flow Based on an Economic Lab-sized Setup

    DEFF Research Database (Denmark)

    Hansen, Lasse; Pedersen, Simon; Yang, Zhenyu

    2013-01-01

    As a kind of periodic phenomenon, the slugging flow in the offshore oil & gas production addresses a lot of attentions, due to its limitation of production rate, periodic overload processing facilities, and even direct cause of emergent shutdown. This work studies the emulation of the riser...... slugging flow in the offshore oil & gas production, by constructing an economical lab-sized setup in the university campus. Firstly, the construction and used components for the lab setup are illustrated; then, the constructed setup is validated by checking the consistency with some existing typical riser...

  14. Analysis of the effects of corrosion probe on riser 241-AN-102-WST-16 during seismic event

    International Nuclear Information System (INIS)

    ZIADA, H.H.

    1998-01-01

    This analysis supports the installation activity of the corrosion probe in Tank 241-AN-102. The probe is scheduled to be installed in Riser 241-AN-102-WST-16 (formerly known as Riser 15B). The purpose of this analysis is to evaluate the potential effect of the corrosion probe on the riser during a credible seismic event. The previous analysis (HNF 1997a) considered only pump jet impingement loading

  15. Reliability-based dynamic positioning of floating vessels with riser and mooring system

    DEFF Research Database (Denmark)

    Fang, Shaoji; Leira, Bernt J.; Blanke, Mogens

    2011-01-01

    To maintain safety of a floating vessel with associated slender components such as risers and mooring line, the vessel is normally kept within a limited region. To specify a safe position in that region, this paper suggests a new position chasing algorithm with the consideration of both riser ang...... to their criticality. An optimal position set-point is produced by minimization of the value of the cost function. Numerical simulations show the effectiveness of the proposed algorithm....

  16. Simulation of inlet and outlet riser break sequences in the N Reactor

    International Nuclear Information System (INIS)

    Bolander, M.A.; Fletcher, C.D.

    1988-02-01

    This report documents work performed at the Idaho National Engineering Laboratory (INEL) in support of the Westinghouse Hanford Company safety analyses of the N Reactor. The RELAP5/MOD2 computer code was used in analyzing two hypothetical transients. The computer code was modified specifically to simulate the refill behavior in the N Reactor process tubes. The transients analyzed were a double-ended rupture of an inlet riser column and a double-ended rupture of an outlet riser column

  17. Fatigue Strength of Titanium Risers - Defect Sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Babalola, Olusegun Tunde

    2001-07-01

    This study is centred on assessment of the fatigue strength of titanium fusion welds for deep-water riser's applications. Deep-water risers are subjected to significant fatigue loading. Relevant fatigue data for titanium fusion welds are very scarce. Hence there is a need for fatigue data and life prediction models for such weldments. The study has covered three topics: Fatigue testing, Fractography and defect assessment, and Fracture Mechanics modelling of fatigue crack growth. Two series of welded grade of titanium consisting of 14 specimens in each series were fatigue tested under constant amplitude loading. Prior to fatigue testing, strain gauge measurements of some specimens was conducted to enable the definition of stress range in the fatigue assessment procedure. The results were compared with finite solid element analysis and related to fatigue stresses in a riser pipe wall. Distribution and geometry of internal and surface defects both in the as-welded and in the post-weld machined conditions were assessed using fractography. This served as a tool to determine the fatigue initiation point in the welds. Fracture mechanics was applied to model fatigue strength of titanium welds with initiation from weld defects. Two different stress intensity factor formulations for embedded eccentrically placed cracks were used for analysis of elliptical cracks with the major axis parallel and close to one of the free surfaces. The methods were combined to give a satisfactory model for crack growth analysis. The model analyses crack growth of elliptical and semi-elliptical cracks in two directions, with updating of the crack geometry. Fatigue strength assessment was conducted using two crack growth models, the Paris-Erdogan relation with no threshold and the Donahue et al. relation with an implied threshold. The model was validated against experimental data, with a discussion on the choice of crack growth model. (author)

  18. Single-shell tank riser resistance to ground test plan

    International Nuclear Information System (INIS)

    Kiewert, L.R.

    1996-01-01

    This Test Procedure provides the general directions for conducting Single-Shell Tank Riser to Earth Measurements which will be used by engineering as a step towards providing closure for the Lightning Hazard Issue

  19. Validation Plan of Turbulence Models for Internal Gas Flow Analysis in a Heated Rectangular Riser Duct

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sin-Yeob; Shin, Dong-Ho; Park, Goon-Cherl; Cho, Hyoung Kyu [Seoul National Univ., Seoul (Korea, Republic of); Kim, Chan-Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    VHTR being developed at Korea Atomic Energy Research Institute adopts an air-cooled Reactor Cavity Cooling System (RCCS) incorporating rectangular riser channels to remove the afterheat emitted from the reactor vessel. Because the performance of RCCS is determined by heat removal rate through the RCCS riser, it is important to understand the heat transfer phenomena in the RCCS riser to ensure the safety of the reactor. In the mixed convection, due to the buoyance force induced by temperature and density differences, local flow structure and heat transfer mode near the heated wall have significantly dissimilar characteristics from both forced convection and free convection. In this study, benchmark calculation was conducted to reproduce the previous statements that V2F turbulence model can capture the mixed convection phenomena with the Shehata's experimental data. Then, the necessity of the model validation for the mixed convection phenomena was confirmed with the CFD analyses for the geometry of the prototype RCCS riser. For the purpose of validating the turbulence models for mixed convection phenomena in the heated rectangular riser duct, validation plan with three experimental tests was introduced. Among them, the flow visualization test facility with preserved cross-section geometry was introduced and a preliminary test result was shown.

  20. Model of a catalytic injection in a riser by means of gamma ray transmission measurements

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Alex E.; Brito, Macio F.P.; Dantas, Carlos C.; Melo, Silvio B., E-mail: alex.emoura@ufpe.br, E-mail: sbm@ufpe.br [Universidade Federal de Pernambuco (DEN/UFPE), Recife, PE (Brazil); Barbosa, Enivaldo S., E-mail: Enivaldo.santos@ufcg.edu.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Departamento de Engenharia Mecanica; Lima, Emerson A.O., E-mail: eal@poli.br [Universidade de Pernambuco, Recife, PE (Brazil). Departamento de Matematica

    2015-07-01

    In Gas solid process involving a solid circulation through a closed loop the knowledge of the Solids Circulation Rate (SCR) is fundamental to control and improve the operation of a circulating fluidized bed system. A valve controls the circulation rate of solids in the riser of a fluid catalytic cracking unit. Initially, to control the catalyst injection in the riser, a rotary valve controlled and measured solid flow injection, but with a limited working time. Due to the fine powder catalyst abrasive action on the valve steel axis, this device stop work. A lab made valve were design to avoiding direct contact of the catalyst with mechanical moving parts in while control solid injection in riser, but do not measure the solid flow like the rotary valve. To control the lab made device a fixed pressure measurement at riser bottom is provided by control setup which corresponds to a given mass/time solid injection. In the present work, we proposed a method to evaluate the control valve based on a non-invasive technique. With gamma ray transmission measurements, in a cross section of the pipe, we developed a model that was used in the control system of the Cold Pilot Unit (CPU). Therefore, the interaction of the gamma ray with solid flow in riser should yield the necessary information for the process control system. A first model approximation consider the solid flow rate injection and solid velocity in riser as proposed in literature. In the CPU control system a Programmable Logic Controller-PLC keeps steady state processing the airflow, pressure profile and solid flow inputs. Additionally to preexisting PLC platform, some LabVIEW algorithms were implemented to achieve a good system performance operational condition. (author)

  1. Model of a catalytic injection in a riser by means of gamma ray transmission measurements

    International Nuclear Information System (INIS)

    Moura, Alex E.; Brito, Macio F.P.; Dantas, Carlos C.; Melo, Silvio B.; Barbosa, Enivaldo S.; Lima, Emerson A.O.

    2015-01-01

    In Gas solid process involving a solid circulation through a closed loop the knowledge of the Solids Circulation Rate (SCR) is fundamental to control and improve the operation of a circulating fluidized bed system. A valve controls the circulation rate of solids in the riser of a fluid catalytic cracking unit. Initially, to control the catalyst injection in the riser, a rotary valve controlled and measured solid flow injection, but with a limited working time. Due to the fine powder catalyst abrasive action on the valve steel axis, this device stop work. A lab made valve were design to avoiding direct contact of the catalyst with mechanical moving parts in while control solid injection in riser, but do not measure the solid flow like the rotary valve. To control the lab made device a fixed pressure measurement at riser bottom is provided by control setup which corresponds to a given mass/time solid injection. In the present work, we proposed a method to evaluate the control valve based on a non-invasive technique. With gamma ray transmission measurements, in a cross section of the pipe, we developed a model that was used in the control system of the Cold Pilot Unit (CPU). Therefore, the interaction of the gamma ray with solid flow in riser should yield the necessary information for the process control system. A first model approximation consider the solid flow rate injection and solid velocity in riser as proposed in literature. In the CPU control system a Programmable Logic Controller-PLC keeps steady state processing the airflow, pressure profile and solid flow inputs. Additionally to preexisting PLC platform, some LabVIEW algorithms were implemented to achieve a good system performance operational condition. (author)

  2. Development of an environment for 3D visualization of riser dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Bernardes Junior, Joao Luiz; Martins, Clovis de Arruda [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica]. E-mails: joao.bernardes@poli.usp.br; cmartins@usp.br

    2006-07-01

    This paper describes the merging of Virtual Reality and Scientific Visualization techniques in the development of Riser View, a multi platform 3D environment for real time, interactive visualization of riser dynamics. Its features, architecture, unusual collision detection algorithm and how up was customized for the project are discussed. Using Open GL through VRK, the software is able to make use of the resources available in most modern Graphics. Acceleration Hardware to improve performance. IUP/LED allows for native loo-and-feel in MS-Windows or Linux platform. The paper discusses conflicts that arise between scientific visualization and aspects such as realism and immersion, and how the visualization is prioritized. (author)

  3. Validation of mathematical models to describe fluid dynamics of a cold riser by gamma ray attenuation

    International Nuclear Information System (INIS)

    Melo, Ana Cristina Bezerra Azedo de

    2004-12-01

    The fluid dynamic behavior of a riser in a cold type FCC model was investigated by means of catalyst concentration distribution measured with gamma attenuation and simulated with a mathematical model. In the riser of the cold model, MEF, 0,032 m in diameter, 2,30 m in length the fluidized bed, whose components are air and FCC catalyst, circulates. The MEF is operated by automatic control and instruments for measuring fluid dynamic variables. An axial catalyst concentration distribution was measured using an Am-241 gamma source and a NaI detector coupled to a multichannel provided with a software for data acquisition and evaluation. The MEF was adapted for a fluid dynamic model validation which describes the flow in the riser, for example, by introducing an injector for controlling the solid flow in circulation. Mathematical models were selected from literature, analyzed and tested to simulate the fluid dynamic of the riser. A methodology for validating fluid dynamic models was studied and implemented. The stages of the work were developed according to the validation methodology, such as data planning experiments, study of the equations which describe the fluidodynamic, computational solvers application and comparison with experimental data. Operational sequences were carried out keeping the MEF conditions for measuring catalyst concentration and simultaneously measuring the fluid dynamic variables, velocity of the components and pressure drop in the riser. Following this, simulated and experimental values were compared and statistical data treatment done, aiming at the required precision to validate the fluid dynamic model. The comparison tests between experimental and simulated data were carried out under validation criteria. The fluid dynamic behavior of the riser was analyzed and the results and the agreement with literature were discussed. The adopt model was validated under the MEF operational conditions, for a 3 to 6 m/s gas velocity in the riser and a slip

  4. The Effect of Stick Stiffness of Friction Models on the Bending Behavior in Non-Bonded Flexible Risers

    OpenAIRE

    Dai, Tianjiao; Ye, Naiquan; Sævik, Svein

    2017-01-01

    This paper investigates the effect of stick stiffness on the bending behavior in non-bonded flexible risers. The stick stiffness was normally implemented in the friction model for calculating the friction stress between layers in such structures. As the stick stiffness may be too small to achieve the plane-surfaces-remain-plane assumption under low contact pressure in some friction models [1], a new friction model was proposed for maintaining the constant stick stiffness in the present work. ...

  5. New tools for steel catenary risers inspection; Novas ferramentas para inspecao de risers tipo SCR

    Energy Technology Data Exchange (ETDEWEB)

    Camerini, Claudio Soligo; Marinho, Carla Alves; Raphael, Fabiana N.; Maia, Carlos [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Freitas, Miguel [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil); Lopes, Ricardo Tadeu; Rocha, Henrique [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia

    2005-07-01

    The Research Center of PETROBRAS and two of the Federal Brazilian Universities, PUC-Rio and UFRJ, have been developing two new projects in order to inspect risers of petroleum production. The first tool is an instrumented pig for profiling internal corrosion, having flexibility under diameter variations and independence related to thickness wall pipeline. The second one is a gammagraphy system remotely operated by ROVs, to be employed in alveoli corrosion and fatigue cracks detection in underwater pipelines. This work shows the trajectory of these two tools, describing laboratory and field tests and the future activities. (author)

  6. Analysis of fluid dynamics to the riser of a FCC cold pilot plant aided with response surface methodology; Analise da fluidodinamica em um riser de FCC de uma unidade piloto a frio com auxilio da metodologia de superficie de resposta

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Kamylla A.L. dos; Luna-Finkler, Christine L.; Lima Filho, Hilario J.B. de [Universidade Federal de Pernambuco (UFPE), Vitoria de Santo Antao, PE (Brazil); Benachour, Mohand; Dantas, Carlos Costa; Santos, Valdemir A. dos [Universidade Catolica de Pernambuco (UNICAP), Recife, PE (Brazil)

    2012-07-01

    It was planned and executed the implementation of a Central Composite Rotatable Design (CCRD) to the riser of a FCC (Fluid Catalytic Cracking) cold pilot plant, to identify the basic fluid dynamic characteristics of this type of reactor. The Fluid Catalytic Cracking is the major process in oil refineries in the world. It is realized in a vertical cylindrical reactor called riser, with a short contact time between the cracking catalyst and vacuum gas oil vapors. The constant evolution of the FCC process has required the analysis of fluid dynamics using computational fluid dynamics (CFD) software. However, analysis of images produced by the application of CFD to study of risers requires preliminary concepts of the relationship between response variables and independent variables. With the CCRD implementation was performed a total of 12 experiments, being 4 full factorial, 4 axial points and 4 central points. The dependent variables were the velocities of the components (cracking catalyst and compressed air) and the pressure drop in the riser. There was a great contribution of solids flow rate for the solid phase velocity and for the pressure drop. The effects of interaction between the flow rate phases are considerably senses in pressure drop through the riser, however, for the velocities of both phases this interaction becomes negligible. (author)

  7. Spectral fatigue analysis of a tensioned riser compliant tower

    NARCIS (Netherlands)

    Karadeniz, H.; Vrouwenvelder, A.C.W.M.; Shi, C.

    1998-01-01

    In this paper, the conceptual Tensioned Riser Compliant Tower (TRCT) structure of the Shell Oil, which is developed for a region of approximately 600 meter water depth of the West of Shetlands in the North Sea, is analyzed by using the SAPOS program of the Delft University of Technology. The fatigue

  8. Helical wire stress analysis of unbonded flexible riser under irregular response

    Science.gov (United States)

    Wang, Kunpeng; Ji, Chunyan

    2017-06-01

    A helical wire is a critical component of an unbonded flexible riser prone to fatigue failure. The helical wire has been the focus of much research work in recent years because of the complex multilayer construction of the flexible riser. The present study establishes an analytical model for the axisymmetric and bending analyses of an unbonded flexible riser. The interlayer contact under axisymmetric loads in this model is modeled by setting radial dummy springs between adjacent layers. The contact pressure is constant during the bending response and applied to determine the slipping friction force per unit helical wire. The model tracks the axial stress around the angular position at each time step to calculate the axial force gradient, then compares the axial force gradient with the slipping friction force to judge the helical wire slipping region, which would be applied to determine the bending stiffness for the next time step. The proposed model is verified against the experimental data in the literature. The bending moment-curvature relationship under irregular response is also qualitatively discussed. The stress at the critical point of the helical wire is investigated based on the model by considering the local flexure. The results indicate that the present model can well simulate the bending stiffness variation during irregular response, which has significant effect on the stress of helical wire.

  9. Reconstruction of Twist Torque in Main Parachute Risers

    Science.gov (United States)

    Day, Joshua D.

    2015-01-01

    The reconstruction of twist torque in the Main Parachute Risers of the Capsule Parachute Assembly System (CPAS) has been successfully used to validate CPAS Model Memo conservative twist torque equations. Reconstruction of basic, one degree of freedom drop tests was used to create a functional process for the evaluation of more complex, rigid body simulation. The roll, pitch, and yaw of the body, the fly-out angles of the parachutes, and the relative location of the parachutes to the body are inputs to the torque simulation. The data collected by the Inertial Measurement Unit (IMU) was used to calculate the true torque. The simulation then used photogrammetric and IMU data as inputs into the Model Memo equations. The results were then compared to the true torque results to validate the Model Memo equations. The Model Memo parameters were based off of steel risers and the parameters will need to be re-evaluated for different materials. Photogrammetric data was found to be more accurate than the inertial data in accounting for the relative rotation between payload and cluster. The Model Memo equations were generally a good match and when not matching were generally conservative.

  10. modelling and modelling and simulation of coking in the riser

    African Journals Online (AJOL)

    eobe

    into the modeling of FCC riser by predicting catalyst coke content as a function of reaction by predicting ... understanding of the process, hence restricting scale up to within the ... MATLAB (R2009a) on a Compaq HP CQ61 laptop. The following ...

  11. Mathematics of flexible risers including pressure and internal flow affects

    Energy Technology Data Exchange (ETDEWEB)

    Seyed, F.B. (John Brown Engineers and Constructors Ltd., London (GB)); Patel, M.H. (University Coll., London (GB). Dept. of Mechanical Engineering)

    1992-01-01

    Derivations are presented for calculation of pressure and internal flow induced forces on flexible risers and other curved pipes using a mathematically rigorous approach. Approximate and exact methods are presented for calculation of pressure forces on straight and curved pipes in two dimensions. The mathematical identity of these equations with those for effective tension is illustrated. The force arising from the flow of an internal fluid of constant density is then calculated and combined with those for pressure forces in derivation of the catenary equations including pressure and internal flow terms. It is shown that internal flow contributes a new term to the expression for effective tension. These governing equations are then reduced for the specific cases of simple catenary, steep-S, lazy-S, steep-wave and lazy-wave risers. In each case, the solution method has been presented and the governing equilibrium and geometric compatability conditions cited. (author).

  12. Refining fault slip rates using multiple displaced terrace risers-An example from the Honey Lake fault, NE California, USA

    Science.gov (United States)

    Gold, Ryan D.; Briggs, Richard W.; Crone, Anthony J.; DuRoss, Christopher B.

    2017-11-01

    Faulted terrace risers are semi-planar features commonly used to constrain Quaternary slip rates along strike-slip faults. These landforms are difficult to date directly and therefore their ages are commonly bracketed by age estimates of the adjacent upper and lower terrace surfaces. However, substantial differences in the ages of the upper and lower terrace surfaces (a factor of 2.4 difference observed globally) produce large uncertainties in the slip-rate estimate. In this investigation, we explore how the full range of displacements and bounding ages from multiple faulted terrace risers can be combined to yield a more accurate fault slip rate. We use 0.25-m cell size digital terrain models derived from airborne lidar data to analyze three sites where terrace risers are offset right-laterally by the Honey Lake fault in NE California, USA. We use ages for locally extensive subhorizontal surfaces to bracket the time of riser formation: an upper surface is the bed of abandoned Lake Lahontan having an age of 15.8 ± 0.6 ka and a lower surface is a fluvial terrace abandoned at 4.7 ± 0.1 ka. We estimate lateral offsets of the risers ranging between 6.6 and 28.3 m (median values), a greater than fourfold difference in values. The amount of offset corresponds to the riser's position relative to modern stream meanders: the smallest offset is in a meander cutbank position, whereas the larger offsets are in straight channel or meander point-bar positions. Taken in isolation, the individual terrace-riser offsets yield slip rates ranging from 0.3 to 7.1 mm/a. However, when the offset values are collectively assessed in a probabilistic framework, we find that a uniform (linear) slip rate of 1.6 mm/a (1.4-1.9 mm/a at 95% confidence) can satisfy the data, within their respective uncertainties. This investigation demonstrates that integrating observations of multiple offset elements (crest, midpoint, and base) from numerous faulted and dated terrace risers at closely spaced

  13. Numerical investigation on effect of riser diameter and inclination on system parameters in a two-phase closed loop thermosyphon solar water heater

    International Nuclear Information System (INIS)

    Aung, Nay Zar; Li, Songjing

    2013-01-01

    Highlights: • Optimum inclination for maximum heat flux changes with latitude of location. • Optimum inclination for maximum heat flux also changes local solar time. • Maximum flow rate increases with increasing of riser tube size. • Maximum mass flow rate is obtained at different inclinations for different risers. • Length of two-phase region depends on inclination angles but not riser tube size. - Abstract: In this work, the effect of riser diameter and its inclination angle on system parameters in a two-phase closed loop thermosyphon solar water heater has been numerically investigated. Here, receivable heat flux by the collector, circulating mass flow rate, driving pressure, total pressure drop, heat transfer coefficient in risers and collector efficiency are defined as system parameters. For this aim, a model of two-phase thermosyphon solar water heater that is acceptable for various inclinations is presented and variations of riser diameter and inclination are considered. The riser tube size is varied from 1.25 cm to 2.5 cm with inclination range 2–75°. The system absolute pressure is set as 3567 Pa and water is chosen as working fluid. The results show that higher inclination angle is required for higher latitude location to obtain maximum solar heat flux. At local solar noon of 21.996 north latitude, the optimum inclination angle increases in the range of 24–44° with increasing of riser diameter giving maximum circulating mass flow rate from 0.02288 kg/s to 0.03876 kg/s. The longer two-phase heat transfer characteristics can be obtained at smaller inclination angles and mass flow rate for all riser tube sizes. Therefore, it is observed that the optimum inclination angles and diameters for solar heat flux, circulating mass flow rate and heat transfer coefficient in two-phase thermosyphon systemdo not coincide. From this work, better understanding and useful information are provided for constructing two-phase thermosyphon solar heaters

  14. Construction Method Study For Installation Of A Large Riser In A Single-Shell Tank

    International Nuclear Information System (INIS)

    Adkisson, D.A.

    2010-01-01

    This study evaluates and identifies a construction method for cutting a hole in a single-shell tank dome. This study also identifies and evaluates vendors for performing the cut. Single-shell tanks (SST) in the 241-C tank farm are currently being retrieved using various retrieval technologies (e.g., modified sluicing). The Hanford Federal Facility Agreement and Consent Order require that the SSTs be retrieved to less than 360 cubic feet of radioactive waste. The current technologies identified and deployed for tank retrieval have not been able to retrieve waste in accordance with the Hanford Federal Facility Agreement and Consent Order. As such, alternative retrieval systems have been proposed and are currently under construction that will have the ability to retrieve waste to this defined level. The proposed retrieval systems will not fit down existing risers. New risers will need to be installed to provide the retrieval systems access to the inside of the SSTs. The purpose of this study is two-fold. The first objective is to identify multiple concrete cutting technologies and perform an initial pre-screening, evaluate the technologies identified for more in-depth analysis, and recommend a technology/methodology for cutting a hole in the tank dome. The identified/pre-screened methods will be evaluated based on the following criteria: (1) Maturity/complexity; (2) Waste generation; (3) Safety; (4) Cost; and (5) Schedule. Once the preferred method is identified to cut the hole in the tank dome, the second objective is to identify, evaluate, and recommend a vendor for the technology selected that will perform the cutting process.

  15. Laboratory measurements of vortex- and wake-induced vibrations of a tandem arrangement of two flexible risers

    Science.gov (United States)

    Liu, Huai-zeng; Wang, Fei; Jiang, Guo-sheng; Guo, Hai-yan; Li, Xiao-min

    2016-03-01

    The dynamic response of two flexible model risers in tandem arrangement immersed in a stepped current was analyzed. The risers, with an external diameter of 20 mm and a total length of 6200 mm, had an aspect ratio of 310. They were hinged to the support structure at the center-to-center distances away 3-12 times the external diameter. The top 1200 mm was exposed to a uniform current at a speed which was up to 0.9 m/s (the Reynolds number was 18000) and the rest in still water. The dynamic responses, which were obtained through the Fiber Bragg Grating strain gauges mounted on the surface, were analyzed by studying the cross-flow amplitudes and modal weights. The cross-flow vibration were observed up to the third mode, and the modal transformation from the second mode to the third mode was clearly observed. The experiment confirmed that the typical vortex-induced vibration (VIV) had occurred on the up-stream riser. But for the down-stream riser, the main excitation mechanism was wake-induced vibration (WIV). The modal transformation of WIV was more complex than that of VIV, which might be helpful for other researchers to study the interference effect.

  16. Flexible Riser Monitoring Using Hybrid Magnetic/Optical Strain Gage Techniques through RLS Adaptive Filtering

    Directory of Open Access Journals (Sweden)

    Daniel Pipa

    2010-01-01

    Full Text Available Flexible riser is a class of flexible pipes which is used to connect subsea pipelines to floating offshore installations, such as FPSOs (floating production/storage/off-loading unit and SS (semisubmersible platforms, in oil and gas production. Flexible risers are multilayered pipes typically comprising an inner flexible metal carcass surrounded by polymer layers and spiral wound steel ligaments, also referred to as armor wires. Since these armor wires are made of steel, their magnetic properties are sensitive to the stress they are subjected to. By measuring their magnetic properties in a nonintrusive manner, it is possible to compare the stress in the armor wires, thus allowing the identification of damaged ones. However, one encounters several sources of noise when measuring electromagnetic properties contactlessly, such as movement between specimen and probe, and magnetic noise. This paper describes the development of a new technique for automatic monitoring of armor layers of flexible risers. The proposed approach aims to minimize these current uncertainties by combining electromagnetic measurements with optical strain gage data through a recursive least squares (RLSs adaptive filter.

  17. Numerical simulations of vortex-induced vibrations of a flexible riser with different aspect ratiosin uniform and shear currents

    Science.gov (United States)

    Duanmu, Yu; Zou, Lu; Wan, De-cheng

    2017-12-01

    This paper aimed at describing numerical simulations of vortex-induced vibrations (VIVs) of a long flexible riser with different length-to-diameter ratio (aspect ratio) in uniform and shear currents. Three aspect ratios were simulated: L/D = 500, 750 and 1 000. The simulation was carried out by the in-house computational fluid dynamics (CFD) solver viv-FOAM-SJTU developed by the authors, which was coupled with the strip method and developed on the OpenFOAM platform. Moreover, the radial basis function (RBF) dynamic grid technique is applied to the viv-FOAM-SJTU solver to simulate the VIV in both in-line (IL) and cross-flow (CF) directions of flexible riser with high aspect ratio. The validation of the benchmark case has been completed. With the same parameters, the aspect ratio shows a significant influence on VIV of a long flexible riser. The increase of aspect ratio exerted a strong effect on the IL equilibrium position of the riser while producing little effect on the curvature of riser. With the aspect ratio rose from 500 to 1 000, the maximum IL mean displacement increased from 3 times the diameter to 8 times the diameter. On the other hand, the vibration mode of the riser would increase with the increase of aspect ratio. When the aspect ratio was 500, the CF vibration was shown as a standing wave with a 3rd order single mode. When the aspect ratio was 1 000, the modal weights of the 5th and 6th modes are high, serving as the dominant modes. The effect of the flow profile on the oscillating mode becomes more and more apparent when the aspect ratio is high, and the dominant mode of riser in shear flow is usually higher than that in uniform flow. When the aspect ratio was 750, the CF oscillations in both uniform flow and shear flow showed multi-mode vibration of the 4th and 5th mode. While, the dominant mode in uniform flow is the 4th order, and the dominant mode in shear flow is the 5th order.

  18. The impact of a grain of sand: increasing production speed in flexible risers generates significant savings in gas production

    NARCIS (Netherlands)

    Bokhorst, E. van; Blokland, H.

    2012-01-01

    Deep-sea oil and gas production normally involves the use of flexible risers that comprise a metal carcass with a large number of enveloping layers that safeguard the integrity of the pipe system. The flexible risers are hung from a floating platform and may be supported by several floating buoys to

  19. Catalyst volumetric fraction simulation in a riser of a cold flow pilot unit with aid of transmission gamma technique

    International Nuclear Information System (INIS)

    Santos, Kamylla A.L. dos; Lima Filho, Hilario J.B. de; Benachour, Mohand; Dantas, Carlos C.; Santos, Valdemir A. dos

    2013-01-01

    Was obtained the radial profile of the catalyst volume fraction in a riser of the cold flow pilot unit of the Fluid Catalytic Cracking (FCC) unit, which was used for adjustment of the entrance conditions of the catalyst in a simulation program by Computational Fluid Dynamics (CFD). The height of the riser of the Cold Flow Pilot Unity (CFPU) utilized is 6.0m and its inner diameter is 0.097 m. A radiation-γ source of Am-241 and a NaI (Tl) detector, with shielding made of lead, have been installed on a steel backing that maintains the geometry of the source-detector-riser and allows to vary the distance from the source to the detector and the radial position in a given cross section of the riser. The data associated with the simulation of volume fraction radial profile of the catalyst were: Fluent software, version 12.0; preprocessor GAMBIT, version 2.3.16; Eulerian approach; structured mesh, cell number of 60000; turbulence model used was k-ε and kinetic theory of granular flow (KTGF) was implemented to describe the solid phase. Comparison of radial profiles simulated and experimental of the catalyst volumetric fraction in the CFPU riser allowed the identification of needs adjustments in the simulation for the input of catalyst, with consequent validation for the proposed model simulation. (author)

  20. A state space approach for the eigenvalue problem of marine risers

    KAUST Repository

    Alfosail, Feras

    2017-10-05

    A numerical state-space approach is proposed to examine the natural frequencies and critical buckling limits of marine risers. A large axial tension in the riser model causes numerical limitations. These limitations are overcome by using the modified Gram–Schmidt orthonormalization process as an intermediate step during the numerical integration process with the fourth-order Runge–Kutta scheme. The obtained results are validated against those obtained with other numerical methods, such as the finite-element, Galerkin, and power-series methods, and are found to be in good agreement. The state-space approach is shown to be computationally more efficient than the other methods. Also, we investigate the effect of a high applied tension, a high apparent weight, and higher-order modes on the accuracy of the numerical scheme. We demonstrate that, by applying the orthonormalization process, the stability and convergence of the approach are significantly improved.

  1. Experimental Plan for Crystal Accumulation Studies in the WTP Melter Riser

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fowley, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-04-28

    This experimental plan defines crystal settling experiments to be in support of the U.S. Department of Energy – Office of River Protection crystal tolerant glass program. The road map for development of crystal-tolerant high level waste glasses recommends that fluid dynamic modeling be used to better understand the accumulation of crystals in the melter riser and mechanisms of removal. A full-scale version of the Hanford Waste Treatment and Immobilization Plant (WTP) melter riser constructed with transparent material will be used to provide data in support of model development. The system will also provide a platform to demonstrate mitigation or recovery strategies in off-normal events where crystal accumulation impedes melter operation. Test conditions and material properties will be chosen to provide results over a variety of parameters, which can be used to guide validation experiments with the Research Scale Melter at the Pacific Northwest National Laboratory, and that will ultimately lead to the development of a process control strategy for the full scale WTP melter. The experiments described in this plan are divided into two phases. Bench scale tests will be used in Phase 1 (using the appropriate solid and fluid simulants to represent molten glass and spinel crystals) to verify the detection methods and analytical measurements prior to their use in a larger scale system. In Phase 2, a full scale, room temperature mockup of the WTP melter riser will be fabricated. The mockup will provide dynamic measurements of flow conditions, including resistance to pouring, as well as allow visual observation of crystal accumulation behavior.

  2. Measurement of density distribution of a cracking catalyst in experimental riser with a sampling procedure for gamma ray tomography

    International Nuclear Information System (INIS)

    Dantas, C.C.; Melo, S.B.; Oliveira, E.F.; Simoes, F.P.M.; Santos, M.G. dos; Santos, V.A. dos

    2008-01-01

    By scanning a riser the number of the gamma ray trajectories and the beam width involve temporal, spatial and density resolutions as they are closely correlated parameters. Therefore, evaluation of parameters and their interaction quantification, certainly, are required in the imaging process. Measuring the density distribution of the catalyst from the FCC - fluid cracking catalytic process in an experimental riser in single beam tomographic system, density resolution is evaluated and correlated with spatial resolution. The beam width Δs inside riser is measured and a criterion for determining spatial resolution is proposed. Experiments are carried out to demonstrate resolution effects of three Δs values: 3.30 x 10 -3 , 6.20 x 10 -3 and 12.00 x 10 -3 m. The gamma beam profile is modeled and a sampling rate according to Nyquist criterion is analyzed. The 4.3%, 8.1% and 15.6% ratios of Δs/R to internal riser radius are correlated to counting time in the sampling procedure. Results are discussed by comparison with values from literature

  3. Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) Study of Mass-Transfer Mechanisms in Riser Flow.

    Science.gov (United States)

    Carlos Varas, Álvaro E; Peters, E A J F; Kuipers, J A M

    2017-05-17

    We report a computational fluid dynamics-discrete element method (CFD-DEM) simulation study on the interplay between mass transfer and a heterogeneous catalyzed chemical reaction in cocurrent gas-particle flows as encountered in risers. Slip velocity, axial gas dispersion, gas bypassing, and particle mixing phenomena have been evaluated under riser flow conditions to study the complex system behavior in detail. The most important factors are found to be directly related to particle cluster formation. Low air-to-solids flux ratios lead to more heterogeneous systems, where the cluster formation is more pronounced and mass transfer more influenced. Falling clusters can be partially circumvented by the gas phase, which therefore does not fully interact with the cluster particles, leading to poor gas-solid contact efficiencies. Cluster gas-solid contact efficiencies are quantified at several gas superficial velocities, reaction rates, and dilution factors in order to gain more insight regarding the influence of clustering phenomena on the performance of riser reactors.

  4. Stochastic dynamic analysis of marine risers considering Gaussian system uncertainties

    Science.gov (United States)

    Ni, Pinghe; Li, Jun; Hao, Hong; Xia, Yong

    2018-03-01

    This paper performs the stochastic dynamic response analysis of marine risers with material uncertainties, i.e. in the mass density and elastic modulus, by using Stochastic Finite Element Method (SFEM) and model reduction technique. These uncertainties are assumed having Gaussian distributions. The random mass density and elastic modulus are represented by using the Karhunen-Loève (KL) expansion. The Polynomial Chaos (PC) expansion is adopted to represent the vibration response because the covariance of the output is unknown. Model reduction based on the Iterated Improved Reduced System (IIRS) technique is applied to eliminate the PC coefficients of the slave degrees of freedom to reduce the dimension of the stochastic system. Monte Carlo Simulation (MCS) is conducted to obtain the reference response statistics. Two numerical examples are studied in this paper. The response statistics from the proposed approach are compared with those from MCS. It is noted that the computational time is significantly reduced while the accuracy is kept. The results demonstrate the efficiency of the proposed approach for stochastic dynamic response analysis of marine risers.

  5. A procedure to identify and to assess risk parameters in a SCR (Steel Catenary Riser) due to the fatigue failure

    Energy Technology Data Exchange (ETDEWEB)

    Stefane, Wania [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Faculdade de Engenharia Mecanica; Morooka, Celso K. [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Dept. de Engenharia de Petroleo. Centro de Estudos de Petroleo; Pezzi Filho, Mario [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). E and P. ENGP/IPMI/ES; Matt, Cyntia G.C.; Franciss, Ricardo [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2009-12-19

    The discovery of offshore fields in ultra deep water and the presence of reservoirs located in great depths below the seabed requires innovative solutions for offshore oil production systems. Many riser configurations have emerged as economically viable technological solutions for these scenarios. Therefore the study and the development of methodologies applied to riser design and procedures to calculate and to dimension production risers, taken into account the effects of mete ocean conditions, such as waves, current and platform motion in the fatigue failure is fundamental. The random nature of these conditions as well as the mechanical characteristics of the riser components are critical to a probabilistic treatment to ensure the greatest reliability for risers and minimum risks associated to different aspects of the operation like the safety of the installation, economical concerns and the environment. The current work presents a procedure of the identification and the assessment of main parameters of risk when considering fatigue failure. Static and dynamic behavior of Steel Catenary Riser (SCR) under the effects of mete ocean conditions and uncertainties related to total cumulative damage (Miner-Palmgren's rule) are taken into account. The methodology adopted is probabilistic and the approach is analytical. The procedure is based on the First Order Reliability Method (FORM) which usually presents low computational effort and acceptable accuracy. The procedure suggested is applied for two practical cases, one using data available from the literature and the second with data collected from an actual Brazilian offshore field operation. For both cases, results of the probability of failure due to fatigue were obtained for different locations along the SCR length connected to a semi-submersible platform. From these results, the sensitivity of the probability of failure due to fatigue for a SCR could be verified, and the most effective parameter could also be

  6. The Architecture and Beyond of Tread and Riser

    Directory of Open Access Journals (Sweden)

    Sai Sanath

    2016-01-01

    The primary constitution of stairs is the arrangement of horizontal and vertical measures known as tread and riser. This is the simplest arrangement that essentially conveys people from one level to the other with required comfort and safety. Steps are a universal symbol with multiple interpretations. They are the most generally used similes in art, philosophy and psychology. Stairs occupy a unique status in the built environment because they not only convey people, but also symbolize the psychological, spiritual and artistic aspects of human nature. The mental significance and symbolic connotations of steps are deeply rooted. Understanding the role of stairs in different spheres of human need and expression is crucial in approaching its design. The pattern of stairs is dependent on the type of materials and other related design considerations. It is one of the unique architectural entities that reflect the various facets of social, psychological, artistic, metaphysical and religious dimensions. The importance of physical activity in the rising sedentary life styles is linked to the design of building elements, especially the staircases. The advancement in technology has displaced the role of stairs into an inconsequential means of emergency escape. But the importance of physical activity in the rising sedentary lifestyle has revitalized the concept of stairs as an active building component. The mono functional approach to staircases in high-rise buildings, especially as the means of escape in emergency situations, indicates that the design of staircases as multi functional element is still under the confines of design explorations. This paper is an attempt to understand the concept of stairs not only from the evolutionary point of view, but also the associated metaphoric meanings and its emerging multi facet identity. The concept of vertical accessibility in the form of tread and riser arrangement makes stairs a timeless phenomenon. The approach to multi utility

  7. An analytic solution of the static problem of inclined risers conveying fluid

    KAUST Repository

    Alfosail, Feras

    2016-05-28

    We use the method of matched asymptotic expansion to develop an analytic solution to the static problem of clamped–clamped inclined risers conveying fluid. The inclined riser is modeled as an Euler–Bernoulli beam taking into account its self-weight, mid-plane stretching, an applied axial tension, and the internal fluid velocity. The solution consists of three parts: an outer solution valid away from the two boundaries and two inner solutions valid near the two ends. The three solutions are then matched and combined into a so-called composite expansion. A Newton–Raphson method is used to determine the value of the mid-plane stretching corresponding to each applied tension and internal velocity. The analytic solution is in good agreement with those obtained with other solution methods for large values of applied tensions. Therefore, it can be used to replace other mathematical solution methods that suffer numerical limitations and high computational cost. © 2016 Springer Science+Business Media Dordrecht

  8. Clashing of risers due to vortex induced vibrations

    Energy Technology Data Exchange (ETDEWEB)

    Teissier, D. [Ecole Superieure d' Ingenieurs de Marseille (ESIM), 13 - Marseille (France)]|[Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France); Scolan, Y.M. [Ecole Superieure d' Ingenieurs de Marseille (ESIM), 13 - Marseille (France); Fontaine, E. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France)

    2004-07-01

    Phenomena such as Vortex Induced Vibrations can potentially damage offshore risers, especially in ar ay configurations. Due to wake interferences, amplification of VIV is observed leading to large displacements which are no more self limited to one di meter as in the case of VIV. In this context, clash ng becomes also an issue. In order to study this problems, Institut Francais du Petrole is developing a Computational Fluid Dynamics code, DeepFlow, devoted to the simulation of two-dimensional flows around risers. The extension to three-dimensional configurations follows from a strip theory for the fluid flow, coupled to a structural model for flexible pipes (DeepLines). The numerical method (Etienne s 1999) developed in DeepFlow allows to solve the two-dimensional Reynolds Averaged Navier-Stokes equations through a mixed representation (Eulerian and Lagrangian) of the flow properties: vorticity and turbulence. The Eulerian method is necessary in the close vicinity of the bodies in order to capture the boundary layer effects with accuracy, whereas the Lagrangian representation, based on a grid-less method is suitable for the flow in the wake. In the present pa-per, this approach is applied to study the flow around two freely moving cylinders. For this test case, there are some numerical results (Sagatum et al, 2002), however instabilities have been experimentally identified (Paidoussis et al, 1998; Zdravkovich, 1985, 2003). The approach has also been improved to solve accurately the interstitial flow when the bodies are very close to each other. Results from a Chimera approach are presented. (authors)

  9. The use of titanium alloys for dynamic risers: a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Torster, F.; Kocak, M.; Santos, J.F. dos [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Werkstofforschung; Hutt, G. [Stolt Comex Seaway Ltd., Aberdeen, (Scotland)

    1997-12-31

    The main topic of this short literature review is to describe the material related aspects concerning the production and purpose of flexible titanium risers for offshore oil and gas production. Metallurgy and alloying of titanium are briefly introduced. The review concentrates on the materials properties that are relevant for the intended use in marine environment. The focus is put on {alpha}+{beta} Ti-alloys, because earlier investigations have shown that this alloy family is the most suitable one for this purpose. Further topics which are taken into account are welding processes for titanium, weld properties and aspects of the associated weld defects as well. This literature review has been carried out at GKSS-Forschungszentrum Geesthacht GmbH within the framework of the project `Titanium Risers for Deepwater Developments (contract nr. OG/175/95), supported by the THERMIE-JOULE Programme of the European Commission. The project consortium is formed by Stolt Comex Seaway Ltd. (UK), Seaflex AS (Norway) and GKSS (Germany). (orig.) [Deutsch] Die vorliegende kurze Literaturrecherche befasst sich vorrangig mit den materialbezogenen Aspekten der Produktion und des Einsatzes von flexiblen `Risern` aus Titanlegierungen fuer die Oel- und Gasfoerderung auf See. Die Metallurgie und das Legieren von Titan werden kurz vorgestellt. Die Recherche konzentriert sich im weiteren auf die Materialeigenschaften, die fuer den vorgesehenen Einsatz in mariner Umgebung von besonderer Bedeutung sind. In erster Linie wird dabei auf {alpha}+{beta}-Titanlegierungen eingegangen, da vorausgegangene Untersuchungen gezeigt haben, dass diese Legierungsfamilie die guenstigsten Eigenschaften fuer das vorgesehene Einsatzgebiet aufweist. Im weiteren werden die Schweissprozesse, die bei Titanlegierungen eingesetzt werden, vorgestellt und die Eigenschaften und moeglichen Schweissfehler der hergestellten Schweissverbindungen gegenuebergestellt. Diese Literaturrecherche wurde im GKSS-Forschungszentrum im

  10. Necessary Tension in Marine Risers Tension des colonnes montantes en mer

    Directory of Open Access Journals (Sweden)

    Lubinski A.

    2006-11-01

    Full Text Available The tension governing transverse static and dynamic deflections in a riser is not the actual tension but the so-called « effective tension » The concept of effective tension and effective compression is thoroughly explained, and means for calculating effective forces are given. Numerical examples are worked out for risers whose length is between 152 m (520 ft and 920 m (3020 ft. The reciprocal of maximum bending moment of the vicinity of the hall joint is plotted versus the effective tension of the ball joint. Bending moments used were obtained through use of static and dynamic computer programs applied ta a variety of conditions of wave loading, use or non-use of buoyant moterial sleeves, etc. The most important parameters affecting riser performance are the effective La tension régissant les déflections transversales statiques et dynamiques d'une colonne montante n'est pas la tension réelle mais ce qu'on appelle « la tension effective ». Le concept de tension ou de compression effective est expliqué en détail et la façon de calculer les forces effectives est indiquée dans cet article. Des exemples numériques sont développés pour des colonnes montantes de longueur comprise entre 152 m (520 ft et 920 m (3 020 ft. On a tracé la courbe de l'inverse du moment fléchissant en fonction de la tension effective à l'articulation. Les moments fléchissants utilisés ont été calculés par ordinateur en utilisant des programmes dynamiques et statiques pour des conditions variées d'action des vagues, la colonne montante étant ou non munie de manchettes de flottabilité, etc. Les deux paramètres les plus importants qui affectent le bon comportement d'une colonne montante sont la tension effective et la charge latérale.

  11. Anchoring FRP Composite Armor in Flexible Offshore Riser Systems

    DEFF Research Database (Denmark)

    Costache, Andrei

    things, they serve for the transportation of hydrocarbons from the subsea facilities to the production and drilling equipment at the sea surface. Flexible risers are the prime choice for connecting floating production, storage and offloading facilities, because they are specially designed for dynamic...... counterpart. A new double grip design with flat faces is proposed, in which the loads are transferred through friction. The behavior of such grip is studied by means of experimental testing and finite element modeling. Several iterations of the grip system were evaluated over the course of the project...

  12. Development of Millimeter-Wave Velocimetry and Acoustic Time-of-Flight Tomography for Measurements in Densely Loaded Gas-Solid Riser Flow

    Energy Technology Data Exchange (ETDEWEB)

    Fort, James A.; Pfund, David M.; Sheen, David M.; Pappas, Richard A.; Morgen, Gerald P.

    2007-04-01

    The MFDRC was formed in 1998 to advance the state-of-the-art in simulating multiphase turbulent flows by developing advanced computational models for gas-solid flows that are experimentally validated over a wide range of industrially relevant conditions. The goal was to transfer the resulting validated models to interested US commercial CFD software vendors, who would then propagate the models as part of new code versions to their customers in the US chemical industry. Since the lack of detailed data sets at industrially relevant conditions is the major roadblock to developing and validating multiphase turbulence models, a significant component of the work involved flow measurements on an industrial-scale riser contributed by Westinghouse, which was subsequently installed at SNL. Model comparisons were performed against these datasets by LANL. A parallel Office of Industrial Technology (OIT) project within the consortium made similar comparisons between riser measurements and models at NETL. Measured flow quantities of interest included volume fraction, velocity, and velocity-fluctuation profiles for both gas and solid phases at various locations in the riser. Some additional techniques were required for these measurements beyond what was currently available. PNNL’s role on the project was to work with the SNL experimental team to develop and test two new measurement techniques, acoustic tomography and millimeter-wave velocimetry. Acoustic tomography is a promising technique for gas-solid flow measurements in risers and PNNL has substantial related experience in this area. PNNL is also active in developing millimeter wave imaging techniques, and this technology presents an additional approach to make desired measurements. PNNL supported the advanced diagnostics development part of this project by evaluating these techniques and then by adapting and developing the selected technology to bulk gas-solids flows and by implementing them for testing in the SNL riser

  13. Mesh refinement of simulation with the AID riser transmission gamma

    International Nuclear Information System (INIS)

    Lima Filho, Hilario J.B. de; Benachour, Mohand; Dantas, Carlos C.; Brito, Marcio F.P.; Santos, Valdemir A. dos

    2013-01-01

    Type reactors Circulating Fluidized Bed (CFBR) vertical, in which the particulate and gaseous phases have flows upward (riser) have been widely used in gasification processes, combustion and fluid catalytic cracking (FCC). These biphasic reactors (gas-solid) efficiency depends largely on their hydrodynamic characteristics, and shows different behaviors in the axial and radial directions. The solids axial distribution is observed by the higher concentration in the base, getting more diluted toward the top. Radially, the solids concentration is characterized as core-annular, in which the central region is highly diluted, consisting of dispersed particles and fluid. In the present work developed a two-dimensional geometry (2D) techniques through simulations in computational fluid dynamics (CFD) to predict the gas-solid flow in the riser type CFBR through transient modeling, based on the kinetic theory of granular flow . The refinement of computational meshes provide larger amounts of information on the parameters studied, but may increase the processing time of the simulations. A minimum number of cells applied to the mesh construction was obtained by testing five meshes. The validation of the hydrodynamic parameters was performed using a range of 241Am source and detector NaI (Tl). The numerical results were provided consistent with the experimental data, indicating that the refined computational mesh in a controlled manner, improve the approximation of the expected results. (author)

  14. Studi Pengaruh Gerak Semi-submersible Drilling Rig dengan Variasi Pre-tension Mooring Line terhadap Keamanan Drilling Riser

    Directory of Open Access Journals (Sweden)

    Arda Arda

    2012-09-01

    Full Text Available Analisis terhadap sistem tambat pada anjungan pengeboran semi-submersible drilling rig perlu dilakukan sebelum dilakukannya operasi di lapangan untuk mengetahui perencanaan sistem tambat yang tepat dan aman. Dalam penelitian ini dilakukan analisa perilaku gerak semi-submersible dengan variasi pre-tension mooring line untuk mengetahui berapa besar pre-tension minimal yang harus digunakan agar operasi pengeboran di lingkungan laut Natuna dapat berjalan dengan aman. Variasi pre-tension yang digunakan adalah sebesar 400kN-2000kN dengan penambahan sebesar 400kN. Karakteristik gerakan semi-submersible diprediksi dengan menghitung RAO free floating dengan pemodelan numerik dalam domain frekuensi. Kemudian dilakukan analisa simulasi sistem lengkap (platform, mooring dan drilling riser dengan pemodelan numerik dalam domain waktu. Hasil yang didapat yakni nilai maksimum tegangan mooring line memenuhi batas kriteria API-RP2SK untuk semua variasi pre-tension dengan safety factor terkecil 2.44. Sudut flex joint drilling riser yang terjadi melewati batas kriteria API-RP16Q pada pre-tension 400kN-800kN yang mencapai 6.20 untuk sudut maksimum dan 4.80 untuk sudut rata-rata. Tegangan von Mises yang terjadi pada drilling riser melebihi kriteria API-RP16Q pada pre-tension 400kN-1200kN karena nilainya mencapai 369 MPa (0.82 yield stress.

  15. On the modelling and the analysis of two-phase flow instabilities in pipeline-riser systems; Modelisation et analyse des instabilites d'ecoulements diphasiques dans les conduites petrolieres du type pipeline-riser

    Energy Technology Data Exchange (ETDEWEB)

    Zakarian, E.

    2000-03-10

    Recent estimations predict that over half the remaining offshore oil and gas reserves are located in deep water and marginal fields. For such reserves, economic recovery methods are required. Then, multiphase flows are transported within pipelines and separated on treatment platforms built in shallow water or processed in onshore facilities. Unfortunately, hydrodynamic instabilities may occur whenever gas and liquid flow in a pipeline, generating serious operating problems. This dissertation presents a new way to model two-phase flows in pipelines such as pipeline-riser systems. Equations are algebraic and differential. Their smoothness depends on the closure laws of the problem such as slip or friction laws. Smooth forms of these closure laws are presented for the first time in this dissertation. Therefore, a mathematical analysis of our model fits into a classical frame: a linear analysis leads to an analytical expression of the boundary between stable and unstable flows. A nonlinear analysis provides for the first time, the bifurcation curves of gas-liquid flows in pipe-riser systems, locally round their stability boundary. (author)

  16. Multiport riser and flange assemblies acceptance test report

    International Nuclear Information System (INIS)

    Precechtel, D.R.; Schroeder, B.K.

    1994-01-01

    This document presents the results of the acceptance test for the multiport riser (MPR) and multiport flange (MPF) assemblies. The accepted MPR and MPF assemblies will be used in support of the hydrogen mitigation project for double-shell waste tank 241-SY-101 and other related projects. The testing described in this document verifies that the mechanical and interface features are operating as designed and that the unit is ready for field service. The objectives of the acceptance testing were as follows: Basic equipment functions and mechanical interfaces were verified; Installation and removal of equipment were demonstrated to the degree possible; Operation of the decon spray system and all valving was confirmed; and the accumulated leak rate of the MPR and MPF assemblies was determined

  17. Study for a stress joint at the top of a SCR (Steel Catenary Risers); Estudo de 'stress joints' para o topo de um SCR (Steel Catenary Risers)

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Elizabeth Frauches Netto; Andrade, Edmundo Queiroz de [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    Steel Catenary Risers, SCRs, need a top connection that bears the force transmitted to the platform. Essentially, two types of connections exist on the market: flex joint and stress joint (SJ). PETROBRAS has a SCR with top connection of flex joint type installed on one of its platforms; however, the company has been studying SJ as an option out of SCR top connection. A stress joint is a monolithic structure and can be inspected during manufacture and service, without so many difficult. They are metal structures composed of a uniform bore inserted in a tapered wall that increases gradually to support the force coming from the riser. The objective of this paper is to present a SJ sensitivity study for a production SCR supposedly hardwired to a unit of production of the semi-submersible type. The data used is based on real SCR data. For this study, global and local analyses were conducted for some models of stress joints, varying some parameters such as material and dimensions, allowing for the verification of some of the critical points of this type of connection. The results obtained will be shown in graphs and tensions maps to illustrate comparatively the critical points of the models analyzed. (author)

  18. Small and Medium Enterprises` (SMEs) Access to Finance: Philippines

    OpenAIRE

    Aldaba, Rafaelita M.

    2012-01-01

    Based on a survey of 97 firms in the garments, textiles, automotive, electrical and electronics, and food manufacturing industries; the paper highlights the difficulties faced by small and medium enterprises (SMEs) in accessing finance. For both firms with access to finance as well as those that did not make any finance request, financing obstacles posed as one of the top four serious problems for the growth of their businesses. The survey indicates the continued dependence of SMEs on interna...

  19. Hybrid Composite Tensile Armour Wires in Flexible Risers: A Multi-scale Model

    OpenAIRE

    Gautam, Mayank; Katnam, Kali-Babu; Potluri, Venkata; Jha, Vivekanand; Latto, J.; Dodds, NI

    2017-01-01

    Traditional carbon-steel armour wires pose limitations (e.g. long spans, weight reduction, corrosion and fatigue) for flexible risers to operate in demanding and deeper water environments. In this context, an alternative to carbon-steel tensile armour wires is proposed recently by the authors (Gautam et al. [1]), comprising of hexagonally packed polymer composite rods with uni-directional fibres and an over-braided (i.e. bi-axial braid with high performance fibres) sleeve. These hybrid compos...

  20. Influence of cross-sectional ratio of down comer to riser on the efficiency of liquid circulation in loop air lift bubble column

    Science.gov (United States)

    Yamamoto, Tatsumi; Kawasaki, Hiroyuki; Mori, Hidetoshi

    2017-11-01

    Loop type bubble columns have good performance of liquid circulation and mass transfer by airlift effect, where the liquid circulation time is an important measurable characteristic parameter. This parameter is affected by the column construction, the aspect ratio of the column, the cross-sectional area ratio of down comer to riser (R), and the superficial gas velocity in the riser (UGR). In this work, the mean gas holdup and the liquid circulation time (TC) have been measured in four types of loop airlift type bubble column: concentric tube internal loop airlift type, rectangular internal loop airlift type, external loop airlift type, external loop airlift with separator. Air and tap water were used as gas and liquid phase, respectively. The results have demonstrated that the mean gas holdup in riser increases in proportion to UGR, and that it in downcomer changes according to the geometric parameters of each bubble column. TC has been found to conform to an empirical equation which depends on UGR and the length of draft tube or division plate in the region of 0.33 < R < 1.

  1. Proximal tibial fracture following anterior cruciate ligament reconstruction surgery: a biomechanical analysis of the tibial tunnel as a stress riser.

    Science.gov (United States)

    Aldebeyan, Wassim; Liddell, Antony; Steffen, Thomas; Beckman, Lorne; Martineau, Paul A

    2017-08-01

    This is the first biomechanical study to examine the potential stress riser effect of the tibial tunnel or tunnels after ACL reconstruction surgery. In keeping with literature, the primary hypothesis tested in this study was that the tibial tunnel acts as a stress riser for fracture propagation. Secondary hypotheses were that the stress riser effect increases with the size of the tunnel (8 vs. 10 mm), the orientation of the tunnel [standard (STT) vs. modified transtibial (MTT)], and with the number of tunnels (1 vs. 2). Tibial tunnels simulating both single bundle hamstring graft (8 mm) and bone-patellar tendon-bone graft (10 mm) either STT or MTT position, as well as tunnels simulating double bundle (DB) ACL reconstruction (7, 6 mm), were drilled in fourth-generation saw bones. These five experimental groups and a control group consisting of native saw bones without tunnels were loaded to failure on a Materials Testing System to simulate tibial plateau fracture. There were no statistically significant differences in peak load to failure between any of the groups, including the control group. The fracture occurred through the tibial tunnel in 100 % of the MTT tunnels (8 and 10 mm) and 80 % of the DB tunnels specimens; however, the fractures never (0 %) occurred through the tibial tunnel of the standard tunnels (8 or 10 mm) (P = 0.032). In the biomechanical model, the tibial tunnel does not appear to be a stress riser for fracture propagation, despite suggestions to the contrary in the literature. Use of a standard, more vertical tunnel decreases the risk of ACL graft compromise in the event of a fracture. This may help to inform surgical decision making on ACL reconstruction technique.

  2. Faulted terrace risers place new constraints on the late Quaternary slip rate for the central Altyn Tagh fault, northwest Tibet

    Science.gov (United States)

    Gold, R.D.; Cowgill, E.; Arrowsmith, J.R.; Chen, X.; Sharp, W.D.; Cooper, K.M.; Wang, X.-F.

    2011-01-01

    The active, left-lateral Altyn Tagh fault defines the northwestern margin of the Tibetan Plateau in western China. To clarify late Quaternary temporal and spatial variations in slip rate along the central portion of this fault system (85??-90??E), we have more than doubled the number of dated offset markers along the central Altyn Tagh fault. In particular, we determined offset-age relations for seven left-laterally faulted terrace risers at three sites (Kelutelage, Yukuang, and Keke Qiapu) spanning a 140-km-long fault reach by integrating surficial geologic mapping, topographic surveys (total station and tripod-light detection and ranging [T-LiDAR]), and geochronology (radiocarbon dating of organic samples, 230Th/U dating of pedogenic carbonate coatings on buried clasts, and terrestrial cosmogenic radionuclide exposure age dating applied to quartz-rich gravels). At Kelutelage, which is the westernmost site (37.72??N, 86.67??E), two faulted terrace risers are offset 58 ?? 3 m and 48 ?? 4 m, and formed at 6.2-6.1 ka and 5.9-3.7 ka, respectively. At the Yukuang site (38.00??N, 87.87??E), four faulted terrace risers are offset 92 ?? 12 m, 68 ?? 6 m, 55 ?? 13 m, and 59 ?? 9 m and formed at 24.2-9.5 ka, 6.4-5.0 ka, 5.1-3.9 ka, and 24.2-6.4 ka, respectively. At the easternmost site, Keke Qiapu (38.08??N, 88.12??E), a faulted terrace riser is offset 33 ?? 6 m and has an age of 17.1-2.2 ka. The displacement-age relationships derived from these markers can be satisfied by an approximately uniform slip rate of 8-12 mm/yr. However, additional analysis is required to test how much temporal variability in slip rate is permitted by this data set. ?? 2011 Geological Society of America.

  3. Two-riser system improves drilling at Auger prospect

    International Nuclear Information System (INIS)

    Gonzalez, R.; Marsh, G.L.; Ritter, P.B.; Mendel, P.E.

    1992-01-01

    This paper reports on a two-rise system (TRS) for drilling deepwater development wells which eliminates some of the limitations of conventional subsea technology and allows flexibility in well programs. Shell Offshore Inc.'s deep exploratory wells in Garden Banks 426 and 471 have encountered drilling problems that were attributed to limitations in casing sizes imposed by conventional subsea drilling systems. These problems are not uncommon in exploratory deepwater, deep well drilling in the Gulf of Mexico. Reservoir depths of up to 19,500 ft true vertical depth (TVD) and 7-in. production casing requirements led to potentially troublesome and expensive well plans. Because of the constraints placed on the development drilling program by completion requirements and directional drilling, a two-riser system was designed and fabricated. Solving such significant drilling problems has reduced overall development costs

  4. Space Access for Small Satellites on the K-1

    Science.gov (United States)

    Faktor, L.

    Affordable access to space remains a major obstacle to realizing the increasing potential of small satellites systems. On a per kilogram basis, small launch vehicles are simply too expensive for the budgets of many small satellite programs. Opportunities for rideshare with larger payloads on larger launch vehicles are still rare, given the complications associated with coordinating delivery schedules and deployment orbits. Existing contractual mechanisms are also often inadequate to facilitate the launch of multiple payload customers on the same flight. Kistler Aerospace Corporation is committed to lowering the price and enhancing the availability of space access for small satellite programs through the fully-reusable K-1 launch vehicle. Kistler has been working with a number of entities, including Astrium Ltd., AeroAstro, and NASA, to develop innovative approaches to small satellite missions. The K-1 has been selected by NASA as a Flight Demonstration Vehicle for the Space Launch Initiative. NASA has purchased the flight results during the first four K-1 launches on the performance of 13 advanced launch vehicle technologies embedded in the K-1 vehicle. On K-1 flights #2-#4, opportunities exist for small satellites to rideshare to low-earth orbit for a low-launch price. Kistler's flight demonstration contract with NASA also includes options to fly Add-on Technology Experiment flights. Opportunities exist for rideshare payloads on these flights as well. Both commercial and government customers may take advantage of the rideshare pricing. Kistler is investigating the feasibility of flying dedicated, multiple small payload missions. Such a mission would launch multiple small payloads from a single customer or small payloads from different customers. The orbit would be selected to be compatible with the requirements of as many small payload customers as possible, and make use of reusable hardware, standard interfaces (such as the existing MPAS) and verification plans

  5. ALARA plan for the Old Hydrofracture Facility tanks contents removal project at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Amendment 1 for Appendix B: Install flex-pipe on tank riser spools

    International Nuclear Information System (INIS)

    1998-01-01

    This amendment to Appendix B contains the specific ALARA evaluations for installing flex-pipe on riser spools to accommodate ventilation duct connections to the north risers of each tank. The work will be a routine task that is part of the Equipment Installation and Mobilization phase of the project. The dose rates were estimated using the recent Radiological Surveillance Section radiological survey: SAAS-97-063S. Task B-6 has been added to the OHF Project ALARA review process to address a field decision to modify an approach to installing the tank ventilation system. The revised approach will incorporate 12-in. diameter, 36-in. long, stainless steel flex-pipe connected to each north riser spool to address the problem of pipe fitting multiple bends and turns expected with the 12-in. PVC duct. This improved approach will reduce the time necessary to install the duct system between the tanks and the ventilation skid. However, the task includes opening the 12-in. riser spool connections to replace the currently installed blind gaskets. Since a riser spool for each tank will be opened, there is a potential for significant personnel exposure and spread of contamination that will addressed through this ALARA review process

  6. Estudo do efeito de um "Riser Blowout" na perfuração de poços de petroleo em aguas profundas

    OpenAIRE

    Heitor Rodrigues de Paula Lima

    1991-01-01

    Resumo: Esta dissertação apresenta uma análise do comportamento da pressão dos fluidos que ocorre durante o especial acidente na perfuração de um poço submarino de petróleo conhecido como "Riser Blowout" ( * ). O modelo usado neste estudo baseia-se na solução do sistema de equações diferenciais parciais que governam o fluxo ascendente da mistura bifásica fluido de perfuração/ gás dentro do espaço anular entre a coluna de perfuração e o "marine riser". As perdas de carga devido a aceleração do...

  7. Comportement mécanique des tuyaux. Influence de la traction, de la pression et du poids linéique. Application aux risers Mechanical Behavior of Pipes and Risers. Influence of Tension, Pressure and Weight

    Directory of Open Access Journals (Sweden)

    Sparks C.

    2006-11-01

    Full Text Available L'influence de la traction, de la pression et du poids linéique sur le comportement d'un tuyau (ou d'un riser a déjà été traitée dans de nombreux articles. Malgré cela, elle est fréquemment mal comprise, ce qui a parfois de; conséquences sérieuses. Par souci de clarté, l'approche de cet article est délibérément très élémentaire. Les problèmes principaux de la flexion, du flambage, de l'allongement et de la contrainte limite, qui sont souvent traités dans des articles différents, sont ici étudiés ensemble d'une façon homogène. On présente des interprétation: physiques, faciles à visualiser, des deux concepts de tension effective et de contrainte effective, dont l'utilisation est très répandue, ainsi que leur rapport avec des notions analogues dans d'autres domaines de l'art de l'ingénieur. La puissance de ces deux concepts est démontrée à la fin de l'article où ils sont utilisés pour résoudre huit problèmes divers. The influence of tension, pressure, and weight on different aspects of pipe and riser behavior has already been the subject of many articles (see references. In spite of this it has frequently been misunderstood, sometimes with serious consequences. The object of this payer is to explain the subject clearly and the approach is therefore deliberately very elementary. The principal problems of bending, buckling, yielding and strains, usually treated in separated papers, are here treated homogeneously. The widely used concepts of effective tension and effective stress are given interpretations, easy to visualise, which are related to analogous concepts in other engineering fields. Finally, eight diverse particular examples of the influence of tension, pressure and weight on pipe and riser behavior, are discussed.

  8. Impact Of Particle Agglomeration On Accumulation Rates In The Glass Discharge Riser Of HLW Melter

    International Nuclear Information System (INIS)

    Kruger, A. A.; Rodriguez, C. A.; Matyas, J.; Owen, A. T.; Jansik, D. P.; Lang, J. B.

    2012-01-01

    The major factor limiting waste loading in continuous high-level radioactive waste (HLW) melters is an accumulation of particles in the glass discharge riser during a frequent and periodic idling of more than 20 days. An excessive accumulation can produce robust layers a few centimeters thick, which may clog the riser, preventing molten glass from being poured into canisters. Since the accumulation rate is driven by the size of particles we investigated with x-ray microtomography, scanning electron microscopy, and image analysis the impact of spinel forming components, noble metals, and alumina on the size, concentration, and spatial distribution of particles, and on the accumulation rate. Increased concentrations of Fe and Ni in the baseline glass resulted in the formation of large agglomerates that grew over the time to an average size of ∼185+-155 μm, and produced >3 mm thick layer after 120 h at 850 deg C. The noble metals decreased the particle size, and therefore significantly slowed down the accumulation rate. Addition of alumina resulted in the formation of a network of spinel dendrites which prevented accumulation of particles into compact layers

  9. Numerical simulation and experimental analysis for a Risers Uphold Sub-Surface Buoy (BSR); Simulacao numerica e ensaio experimental da Boia de Sub-superficie de Suporte de Risers - BSSR

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Jairo B. de; Almeida, Jose Carlos L. de [PETROBRAS, Rio de Janeiro, RJ (Brazil); Rangel, Marcos; Fernandes, Antonio C.; Santos, Melquisedec F. dos; Sales Junior, Joel Sena [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE)

    2004-07-01

    This paper presents results, numeric and experimental, due to installation operation of a Risers Uphold Sub-Surface Buoy, (BSR). This kind of installation developed by PETROBRAS is unique in the world. The work of BSR installation was based on a numeric pre analysis to verify the system and determine the main parameters to be experimentally verified. The second phase of the work was the experimental analysis in a deep water ocean basin. s. The work describes the BSR and their main accessories, the experimental environment and the model constructed in aluminum in a 1:12 scale and the main results. (author)

  10. 75 FR 26091 - Safety Zone; Riser for DEEPWATER HORIZON at Mississippi Canyon 252 Outer Continental Shelf MODU...

    Science.gov (United States)

    2010-05-11

    ... the Gulf of Mexico AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is... personnel involved in oil pollution response efforts. Placing a safety zone around the riser will... the water's surface and subsurface. DATES: Effective Date: This rule is effective in the CFR on May 11...

  11. Deployment Plan for Small Roving Annulus Inspection Vehicle

    International Nuclear Information System (INIS)

    Minichan, R.

    2002-01-01

    The Small Roving Annulus Inspection Vehicle (SRAIV) is a modified commercially available wall crawler designed to supplement the In-Service Inspection (ISI) of Savannah River Site (SRS) Waste tanks. The SRAIV provides an improved capability to achieve a more complete inspection of the tank walls than existing methods. The SRAIV will be deployed through annulus risers in the tank to gain access to tank walls requiring inspection. The SRAIV will be deployed using a manually operated deployment pole and will be coupled to the wall using permanent magnet wheels. Navigation will be performed from the remote console where pictorial views can be displayed from the on-board cameras. The unit will incorporate multiple UT transducers for traditional weld examination. In addition, a specially developed Tandem Synthetic Aperture Focusing Technique (TSAFT) UT scanning bridge can be attached to provide further investigation of the knuckle region while the vehicle remains on the vertical surface of the tank wall. In summary, the SRAIV will provide features that enhance and expand the capability of the SRS ISI program

  12. Implications of access hole size on tank waste retrieval system design and cost

    International Nuclear Information System (INIS)

    Babcock, S.M.; Kwon, D.S.; Burks, B.L.; Stoughton, R.S.; Evans, M.S.

    1994-05-01

    The DOE Environmental Restoration and Waste Management Robotics Technology Development Program has been investigating the application of robotics technology to the retrieval of waste from single-shell storage tanks for several years. The use of a large, ''long-reach'' manipulator to position and orient a variety of tools and other equipment has been recommended. The objective of this study is to determine the appropriate access hole size for the tank waste retrieval system installation. Previous reports on the impact of access hole size on manipulator performance are summarized. In addition, the practical limitation for access hole size based on structural limitations of the waste storage tanks, the state-of-the-art size limitations for the installation of new risers, the radiation safety implications of various access hole sizes, and overall system cost implications are considered. Basic conclusions include: (1) overall cost of remediation will; be dominated by the costs of the balance of plant and time required to perform the task rather than the cost of manipulator hardware or the cost of installing a riser, (2) the most desirable solution from a manipulator controls point of view is to make the manipulator as stiff as possible and have as high as possible a natural frequency, which implies a large access hole diameter, (3) beyond some diameter; simple, uniform cross-section elements become less advantageous from a weight standpoint and alternative structures should be considered, and (4) additional shielding and contamination control measures would be required for larger holes. Parametric studies summarized in this report considered 3,790,000 1 (1,000,000 gal) tanks, while initial applications are likely to be for 2,840,000 1 (750,000 gal) tanks. Therefore, the calculations should be somewhat conservative, recognizing the limitations of the specific conditions considered

  13. Learning control for riser-slug elimination and production-rate optimization for an offshore oil and gas production process

    DEFF Research Database (Denmark)

    Pedersen, Simon; Løhndorf, Petar Durdevic; Yang, Zhenyu

    2014-01-01

    , (ii) maximizing the production rate at the riser of an offshore production platform, by manipulating a topside choke valve through a learning switching model-free PID controller. The results show good steady-state performance, though a long settling time due to the unknown reference for no slugging...

  14. HDPE (High Density Polyethylene) pipeline and riser design in Guanabara Bay: challenges and solutions

    Energy Technology Data Exchange (ETDEWEB)

    Bomfimsilva, Carlos; Jorge, Joao Paulo Carrijo; Schmid, Dominique; Gomes, Rodrigo Klim [INTECSEA, Sao Paulo, SP (Brazil); Lima, Alexander Piraja [GDK, Salvador, BA (Brazil)

    2009-12-19

    Worldwide shipments of plastic pipes are forecasted to increase 5.2% per year since 2008, being commonly used for water supply and sewage disposal. The HDPE (High Density Polyethylene) pipes have been applied recently to deliver potable water and fire fighting water for the main pier of the LNG system in Guanabara Bay, Rio de Janeiro. The system contains three sizes of pipe outside diameter, 110 mm and 160 mm for water supply, and 500 mm for the fire fighting system. The main design challenges of the pipeline system included providing on-bottom stability, a suitable installation procedure and a proper riser design. The on-bottom stability calculations, which are quite different from the conventional steel pipelines, were developed by designing concrete blocks to be assembled on the pipeline in a required spacing to assure long term stability, knowing that plastic pipes are buoyant even in flooded conditions. The installation procedure was developed considering the lay down methodology based on surface towing technique. The riser was designed to be installed together with additional steel support structure to allow the entire underwater system to have the same plastic pipe specification up to the surface. This paper presents the main challenges that were faced during the design of the HDPE pipelines for the LNG system in Guanabara Bay, addressing the solutions and recommendations adopted for the plastic underwater pipeline system.

  15. Numerical simulation of thermal-hydraulic processes in the riser chamber of installation for clinker production

    Directory of Open Access Journals (Sweden)

    Borsuk Grzegorz

    2016-03-01

    Full Text Available Clinker burning process has a decisive influence on energy consumption and the cost of cement production. A new problem is to use the process of decarbonization of alternative fuels from waste. These issues are particularly important in the introduction of a two-stage combustion of fuel in a rotary kiln without the typical reactor-decarbonizator. This work presents results of numerical studies on thermal-hydraulic phenomena in the riser chamber, which will be designed to burn fuel in the system where combustion air is supplied separately from the clinker cooler. The mathematical model is based on a combination of two methods of motion description: Euler description for the gas phase and Lagrange description for particles. Heat transfer between particles of raw material and gas was added to the numerical calculations. The main aim of the research was finding the correct fractional distribution of particles. For assumed particle distribution on the first stage of work, authors noted that all particles were carried away by the upper outlet to the preheater tower, what is not corresponding to the results of experimental studies. The obtained results of calculations can be the basis for further optimization of the design and operating conditions in the riser chamber with the implementation of the system.

  16. Assessing the Impact of Internet Access on Household Income and Financial Performance of Small Farms

    OpenAIRE

    Khanal, Aditya R.; Mishra, Ashok K.

    2013-01-01

    With increased focus on survival strategies for small farm businesses, we investigate the impact of Internet access on income and farm expenses of small farm business and households. Using a nation-wide farm-level data in the U.S. and non-parametric matching estimators, the study finds a significant positive impact of Internet access on total household and off-farm income.

  17. Diagnosis of Catalyst Cooler and Riser in RFCC using Sealed gamma-ray Source

    International Nuclear Information System (INIS)

    Kim, Jin Seop; Kim, Jong Bum; Jung, Sung Hee; Kim, Jae Ho

    2005-12-01

    With a quantitative growth of the petroleum industry, a lot of budget are spent for the maintenance and repairs of facilities related to the process annually. Among them, the RFCC(residual fluid catalytic cracking) is a highly value-added unit which converts gas oil and heavier streams to lighter, more valuable products such as propylene, gasoline by an injection of atmospheric residue into the fluided catalyst. In this study, field experiments were performed to analyze the reasons of an abnormal operation in the catalyst cooler and the catalyst riser belonged to the RFCC unit respectively and to estimate the amount of seriousness using sealed gamma-ray source( 60 Co). The catalyst cooler functions cooling for the regeneration of a catalyst, which will be used to a new media in the RFCC unit. The catalyst riser, while, plays an important part in transporting to next cyclotron steps by mixing of an oil, steam and a catalyst mechanically. The purposes of this study is what was the condition of catalyst flow pattern and whether the coke was produced in an inside process or not. Gamma radiation counts were measured by the detector(NaI) positioned outside the pipe-wall diametrically opposite to the gamma source with a regular space. From the results, the section different from the distribution pattern of nearby catalyst in a facility was found. And this became the definitive information to a process operator. Diagnosis technique using gamma radiation source is proved to be the effective and reliable method in providing information on the media distribution in a facility

  18. Influence of riser-induced slugs on the downstream separation processes

    DEFF Research Database (Denmark)

    Pedersen, Simon; Løhndorf, Petar Durdevic; Yang, Zhenyu

    2017-01-01

    In Oil & Gas installations the severe slug is an undesired flow regime due to the negative impact on the production rate and facility safety. This study will evaluate the severe riser-induced slugs’ influence to a typical separation process, consisting of a 3-phase gravity separator physically...... linked to a de-oiling hydrocyclone, based on experimental tests performed on a laboratory testing facility. Several scenarios are compared, while three PID controllers’ coefficients are kept constant for all the tests: The separator pressure, water level, and hydrocyclone pressure-drop-ratio (PDR......) controllers. Each respective scenario makes a comparison between uncontrolled, open-, and closed-loop anti-slug control configurations. It is concluded that both open- and closed-loop anti-slug control strategies improve the water level and PDR setpoint tracking equally well, but that the closed-loop strategy...

  19. The modeling of quadratic B-splines surfaces for the tomographic reconstruction in the FCC- type-riser

    International Nuclear Information System (INIS)

    Vasconcelos, Geovane Vitor; Dantas, Carlos Costa; Melo, Silvio de Barros; Pires, Renan Ferraz

    2009-01-01

    The 3D tomography reconstruction has been a profitable alternative in the analysis of the FCC-type- riser (Fluid Catalytic Cracking), for appropriately keeping track of the sectional catalyst concentration distribution in the process of oil refining. The method of tomography reconstruction proposed by M. Azzi and colleagues (1991) uses a relatively small amount of trajectories (from 3 to 5) and projections (from 5 to 7) of gamma rays, a desirable feature in the industrial process tomography. Compared to more popular methods, such as the FBP (Filtered Back Projection), which demands a much higher amount of gamma rays projections, the method by Azzi et al. is more appropriate for the industrial process, where the physical limitations and the cost of the process require more economical arrangements. The use of few projections and trajectories facilitates the diagnosis in the flow dynamical process. This article proposes an improvement in the basis functions introduced by Azzi et al., through the use of quadratic B-splines functions. The use of B-splines functions makes possible a smoother surface reconstruction of the density distribution, since the functions are continuous and smooth. This work describes how the modeling can be done. (author)

  20. IODP Expedition 319, NanTroSEIZE Stage 2: First IODP Riser Drilling Operations and Observatory Installation Towards Understanding Subduction Zone Seismogenesis

    Directory of Open Access Journals (Sweden)

    Sean Toczko

    2010-09-01

    Full Text Available The Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE is a major drilling project designed to investigate fault mechanics and the seismogenic behavior of subduction zone plate boundaries. Expedition 319 is the first riser drilling operation within scientific ocean drilling. Operations included riser drilling at Site C0009 in the forearc basin above the plate boundary fault, non-riser drilling at Site C0010 across the shallow part of the megasplay faultsystem—which may slip during plate boundary earthquakes—and initial drilling at Site C0011 (incoming oceanic plate for Expedition 322. At Site C0009, new methods were tested, including analysis of drill mud cuttings and gas, and in situ measurements of stress, pore pressure, and permeability. These results, in conjunction with earlier drilling, will provide a the history of forearc basin development (including links to growth of the megasplay fault system and modern prism, b the first in situ hydrological measurements of the plate boundary hanging wall, and c integration of in situ stress measurements (orientation and magnitude across the forearc and with depth. A vertical seismic profile (VSP experiment provides improved constraints on the deeper structure of the subduction zone. At Site C0010, logging-while-drilling measurements indicate significantchanges in fault zone and hanging wall properties over short (<5 km along-strike distances, suggesting different burial and/or uplift history. The first borehole observatory instruments were installed at Site C0010 to monitor pressure and temperature within the megasplay fault zone, and methods of deployment of more complex observatoryinstruments were tested for future operations.

  1. A combined wear-fatigue design methodology for fretting in the pressure armour layer of flexible marine risers

    OpenAIRE

    O'Halloran, S.M.; Shipway, P.H.; Connaire, A.D.; Leen, Sean B.; Harte, A.M.

    2017-01-01

    This paper presents a combined experimental and computational methodology for fretting wear-fatigue prediction of pressure armour wire in flexible marine risers. Fretting wear, friction and fatigue parameters of pressure armour material have been characterised experimentally. A combined fretting wear-fatigue finite element model has been developed using an adaptive meshing technique and the effect of bending-induced tangential slip has been characterised. It has been shown that a surface dama...

  2. Impact of Users Identities and Access Conditions on Downlink Performance in Closed Small-Cell Networks

    KAUST Repository

    Radaydeh, Redha; Gaaloul, Fakhreddine; Alouini, Mohamed-Slim

    2015-01-01

    This paper investigates the effect of various operation parameters on the downlink user performance in overlaid small-cell networks. The case study considers closed-access small cells (e.g., femtocells), wherein only active authorized user

  3. Access to finance for micro, small and medium business units in Serbian agribusiness

    Directory of Open Access Journals (Sweden)

    Sedlak Otilija

    2016-01-01

    Full Text Available Micro, small and medium business units contribute to development of agribusiness only if adequate financial resources for founding and development are given. This paper analyzes the possibilities of financing micro, small and medium legal entities in agribusiness in Serbia, compared to large enterprises. Empirical research included a survey comprising 119 agribusiness units, grouped into three categories dependent on their size. The aim was to confirm that there are substantial differences between units of different sizes, concerning possibilities of accessing bank loans and concerning the process of evaluation of conditions for credit approval. Also, aim was to determine differences between the uses of necessary key economic measures in agribusiness. Results showed significant differences between each group of business units for the majority of the observed parameters. Consequently the small and medium-sized enterprises (SMEs sector and especially entrepreneurs and farmers (micro units only have limited access to financial resources and more financing costs compared to large enterprises.

  4. SCALING SOLID RESUSPENSION AND SORPTION FOR THE SMALL COLUMN ION EXCHANGE PROCESSING TANK

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M.; Qureshi, Z.

    2010-12-14

    The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing 1.3 million gallon waste tank (i.e., Tank 41H) to house the process. Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for suspending and resuspending Monosodium Titanate (MST), Crystalline Silicotitanate (CST), and simulated sludge. In addition, SRNL will also be conducting pilot-scale tests to determine the mixing requirements for the strontium and actinide sorption. As part of this task, the results from the pilot-scale tests must be scaled up to a full-scale waste tank. This document describes the scaling approach. The pilot-scale tank is a 1/10.85 linear scale model of Tank 41H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 41H. The pump locations correspond to the proposed locations in Tank 41H by the SCIX Program (Risers B5 and B2 for two pump configurations and Risers B5, B3, and B1 for three pump configurations). MST additions are through Riser E1, the proposed MST addition riser in Tank 41H. To determine the approach to scaling the results from the pilot-scale tank to Tank 41H, the authors took the following approach. They reviewed the technical literature for methods to scale mixing with jets and suspension of solid particles with jets, and the technical literature on mass transfer from a liquid to a solid particle to develop approaches to scaling the test data. SRNL assembled a team of internal experts to review the scaling approach and to identify alternative approaches that should be considered.

  5. Student Access to Information Technology and Perceptions of Future Opportunities in Two Small Labrador Communities

    Directory of Open Access Journals (Sweden)

    Della Healey

    2002-02-01

    Full Text Available The potential of information technology is increasingly being recognized for the access it provides to educational and vocational opportunities. In Canada, many small schools in rural communities have taken advantage of information technologies to help overcome geographic isolation for students. This article is about students in two small and geographically isolated Labrador communities. Twenty senior students were found to have varying degrees of access to information technologies. Differences were found in their perceptions of the benefits of information technology for their educational and vocational futures.

  6. Steel catenary riser design based on coupled analysis methodology; Projeto de um riser rigido em catenaria baseado em metodologia de analise acoplada

    Energy Technology Data Exchange (ETDEWEB)

    Bahiense, Rodrigo A.; Rodrigues, Marcos V. [Det Norske Veritas (DNV), Rio de Janeiro, RJ (Brazil)

    2008-07-01

    Due to adoption of oil and gas production systems to deep and ultra-deep water, achieving frontiers that were not conceivable before, research in computational methods has contributed to implementation of sophisticated and efficient numerical tools in order to perform simulations considering those operational conditions. Thus, this work presents a steel catenary riser (SCR) design which is connected to a semi-submersible platform where the applied motions to SCR are obtained from analyses based on de-coupled and coupled methodologies. With increase of the line number of the system and water depth, the effects due to coupling of the lines on the platform motions are significant. It can be observed from performed evaluations for a floating production system, comparing the obtained results for SCR under extreme and fatigue conditions when it was submitted to the platform motions considering both methodologies mentioned. So, from the results obtained it can be concluded that for production system evaluated the adoption of decoupled methodology presents more conservative results. Thus the adoption of the coupled model associated to design practice of production lines presents as an alternative more realist and accurate to provide the optimization in the design of these structures. (author)

  7. Spill containment devices and their installation

    International Nuclear Information System (INIS)

    Sunderhaus, C.A.; Butterfield, E.J.; Kesterman, J.E.; Lamping, F.G.

    1993-01-01

    A spill containment device adapted for mounting on the upper end the riser pipe of an underground storage tank for liquid fuel, or other hazardous liquids, said device is described comprising a container adapted for rigid, sealed connection with a riser pipe, and having an upper access opening, and lid means for sealingly closing the upper access opening, said container being characterized in that it is compositely formed and comprises a base member having means for rigidly connecting it with the riser pipe, a shell like body member rigidly and sealingly joined to the base member, and an upper member rigidly and sealingly joined to the body member and defining the upper access opening of the container

  8. Roadside Infrastructure for Safer European Roads (RISER) D06: European Best Practice for Roadside Design: Guidelines for Roadside Infrastructure on New and Existing Roads

    NARCIS (Netherlands)

    Thomson, R.; Fagerlind, H.; Martinez, A.V.; Amenguel, A.; Naing, C.; Hill, J.; Hoschopf, H.; Dupré, G.; Bisson, O.; Kelkka, M.; Horst, A.R.A. van der; Garcia, J.

    2006-01-01

    The European Commission Directorate General for Transportation and Energy (DGTREN) sponsored a research project to investigate the best practice guidelines for roadside infrastructure. The RISER consortium has compiled the following document which is a synthesis of existing practice in Europe with

  9. Impact of increasing market access on a tropical small-scale fishery

    Science.gov (United States)

    Stevens, Kara; Irwin, Brian J.; Kramer, Daniel; Urquhart, Gerald

    2014-01-01

    Small-scale fisheries have historically been marginalized in management and policy investments, and they often remain under-reported in national economic and fisheries statistics. Even so, small-scale fisheries are not entirely buffered from the impacts of globalization, such as the introduction and expansion of markets. This study measures the long-term impact of market-access on a coastal fishery on Nicaragua׳s remote Atlantic Coast from approximately the time when fishermen had access to stable and predictable local markets until the present, when the region has been transformed by road connection. In the last four years, fisheries trade has expanded as road connection has facilitated export to distant markets. Fishery-independent surveys were used to measure changes in indicators of fish-community status such as length-frequency, mean trophic level, and relative biomass. Species-level changes in relative biomass of common snook Centropomus undecimalis and gafftopsail catfish Bagre marinus were also evaluated since these species are the most economically valuable and likely account for the most fish biomass in the system. Using historical records, reports, current observations and interviews, changes in indicators of fishing intensity and market access over the past 17 years were assessed. From 1994 to 2011, community and species-specific metrics of the lagoon fishery declined significantly across all indicators examined. The potential social and economic outcomes of the decline in the fishery are far-reaching for the region, because this tropical fishery comprises the main source of protein and income for residents of twelve indigenous and Afro-descendent communities.

  10. Effect of bidirectional internal flow on fluid–structure interaction dynamics of conveying marine riser model subject to shear current

    Directory of Open Access Journals (Sweden)

    Zheng-Shou Chen

    2012-03-01

    Full Text Available This article presents a numerical investigation concerning the effect of two kinds of axially progressing internal flows (namely, upward and downward on fluid–structure interaction (FSI dynamics about a marine riser model which is subject to external shear current. The CAE technology behind the current research is a proposed FSI solution, which combines structural analysis software with CFD technology together. Efficiency validation for the CFD software was carried out first. It has been proved that the result from numerical simulations agrees well with the observation from relating model test cases in which the fluidity of internal flow is ignorable. After verifying the numerical code accuracy, simulations are conducted to study the vibration response that attributes to the internal progressive flow. It is found that the existence of internal flow does play an important role in determining the vibration mode (/dominant frequency and the magnitude of instantaneous vibration amplitude. Since asymmetric curvature along the riser span emerges in the case of external shear current, the centrifugal and Coriolis accelerations owing to up- and downward internal progressive flows play different roles in determining the fluid–structure interaction response. The discrepancy between them becomes distinct, when the velocity ratio of internal flow against external shear current is relatively high.

  11. Transportation Limitation Access to the Small Islands (Case Study: Banggai Laut Regency)

    Science.gov (United States)

    Sunarti, S.

    2018-02-01

    Indonesia is as an archipelago and maritime country, the large number of Islands owned and scattered in all directions makes a challenge for the Government in equitable development. Development in Indonesia has not been spread evenly and tends to focus on the big island, while the smaller islands are still far behind and lack of government attention. One of them is the lack of infrastructure especially the access to the small islands. Among the small islands in Indonesia with minimal maritime infrastructure or transportation is Banggai Laut Regency, Central Sulawesi Province. This Regency is a new regency that separate itself from its previous regency that is Banggai Kepulauan Regency in about 4 years ago. For the development of the Banggai Laut Regency, access to reach that regency is quite difficult. Therefore, the aim of this research is to find infrastructure development strategy to support the development of Banggai Laut Regency. The research method used was the concurrent model mixed method. Data collection method was done with primary data through field observation and interview, secondary data through literature and document review. Analytical techniques used are qualitative descriptive and Map Overlay techniques using GIS to describe the characteristics of study areas and spatial relationships between islands. The results of this research conclude that the Banggai Laut Regency requires infrastructure development particularly maritime transportation to enhance accessibility of the community headed to Banggi Laut Regency or headed to another island from the Banggai Laut Regency.

  12. Microsoft Access Small Business Solutions State-of-the-Art Database Models for Sales, Marketing, Customer Management, and More Key Business Activities

    CERN Document Server

    Hennig, Teresa; Linson, Larry; Purvis, Leigh; Spaulding, Brent

    2010-01-01

    Database models developed by a team of leading Microsoft Access MVPs that provide ready-to-use solutions for sales, marketing, customer management and other key business activities for most small businesses. As the most popular relational database in the world, Microsoft Access is widely used by small business owners. This book responds to the growing need for resources that help business managers and end users design and build effective Access database solutions for specific business functions. Coverage includes::; Elements of a Microsoft Access Database; Relational Data Model; Dealing with C

  13. "I've Never Heard of It Before": Awareness of Open Access at a Small Liberal Arts University

    Science.gov (United States)

    Kocken, Gregory J.; Wical, Stephanie H.

    2013-01-01

    Small colleges and universities, often late adopters of institutional repositories and open access initiatives, face challenges that have not fully been explored in the professional literature. In an effort to gauge the level of awareness of open access and institutional repositories at the University of Wisconsin-Eau Claire (UWEC), the authors of…

  14. Energy access and security strategies in Small Island Developing States

    International Nuclear Information System (INIS)

    Wolf, Franziska; Surroop, Dinesh; Singh, Anirudh; Leal, Walter

    2016-01-01

    Small Islands Developing States (SIDS) are isolated and surrounded by ocean. The generation and use of energy resources are two very important aspects for the development of SIDS. Unfortunately, most of SIDS do not use their potential in respect of energy resources, and they as a result have to depend on the import of fossil fuels in order to meet their energy needs. This increases the overall vulnerability of SIDS as they have to depend on the rising or fluctuating fossil fuels prices. Some SIDS, especially in the geographically dispersed Pacific region, do not have proper access to energy whereas other SIDS struggle more with energy security issue. At the same time, SIDS are most vulnerable to the impacts and effects of climate change, as they are among the ones to be most severely affected in case of natural calamities and sea-level rise. Drawing on experiences from Fiji and Mauritius, this paper explains core elements related to energy access and security in SIDS, contextualizes and discusses barriers and list some of the strategies that may be used to ensure access to and a continuous supply of energy in SIDS. A situational analysis of two SIDS outlines their current energy situation and compares their energy policies to globally accepted criteria for SIDS policies as well as with each other. It is claimed that the diverging energy performances of Fiji and Mauritius cannot be explained by policies differences. The reasons for the varying energy performances may therefore lie in the administrative and institutional mechanisms used by the two countries in implementing their energy policies. Finally, to enable SIDS to reduce their overall vulnerability and become truly sustainable islands, it is recommended to undertake careful assessments of the particular local contexts under which island energy regimes operate. - Highlights: • Core elements related to energy access/security in SIDS, barriers and strategies. • Situational analysis of two SIDS: Fiji and

  15. Glass melter assembly for the Hanford Waste Vitrification Plant

    International Nuclear Information System (INIS)

    Chen, A.E.; Russell, A.; Shah, K.R.; Kalia, J.

    1993-01-01

    The Hanford Waste Vitrification Plant (HWVP) is designed to solidify high level radioactive waste by converting it into stable borosilicate after mixing with glass frit and water. The heart of this conversion process takes place in the glass melter. The life span of the existing melter is limited by the possible premature failure of the heater assembly, which is not remotely replaceable, in the riser and pour spout. A goal of HWVP Project is to design remotely replaceable riser and pour spout heaters so that the useful life of the melter can be prolonged. The riser pour spout area is accessible only by the canyon crane and impact wrench. It is also congested with supporting frame members, service piping, electrode terminals, canister positioning arm and other various melter components. The visibility is low and the accessibility is limited. The problem is further compounded by the extreme high temperature in the riser core and the electrical conductive nature of the molten glass that flows through it

  16. Small-Area Estimation of Spatial Access to Care and Its Implications for Policy.

    Science.gov (United States)

    Gentili, Monica; Isett, Kim; Serban, Nicoleta; Swann, Julie

    2015-10-01

    Local or small-area estimates to capture emerging trends across large geographic regions are critical in identifying and addressing community-level health interventions. However, they are often unavailable due to lack of analytic capabilities in compiling and integrating extensive datasets and complementing them with the knowledge about variations in state-level health policies. This study introduces a modeling approach for small-area estimation of spatial access to pediatric primary care that is data "rich" and mathematically rigorous, integrating data and health policy in a systematic way. We illustrate the sensitivity of the model to policy decision making across large geographic regions by performing a systematic comparison of the estimates at the census tract and county levels for Georgia and California. Our results show the proposed approach is able to overcome limitations of other existing models by capturing patient and provider preferences and by incorporating possible changes in health policies. The primary finding is systematic underestimation of spatial access, and inaccurate estimates of disparities across population and across geography at the county level with respect to those at the census tract level with implications on where to focus and which type of interventions to consider.

  17. A case study in flow assurance of a pipeline-riser system using OLGA

    Energy Technology Data Exchange (ETDEWEB)

    Nemoto, Rafael Horschutz; Balino, Jorge Luis [Nucleo de Dinamica e Fluidos. Dept. de Engenharia Mecanica. Universidade de Sao Paulo (EP/USP), SP (Brazil)], e-mails: rafael.nemoto@usp.br, jlbalino@usp.br; Tanaka, Rafael Loureiro; Godinho, Carlos Alberto [Prysmian Cables and Systems, Cariacica, ES (Brazil)], e-mails: rafael.tanaka@prysmian.com, carlos.godinho@prysmian.com

    2010-07-01

    In this paper, a case study in flow assurance is performed considering an offshore operating system, using the software OLGA. As operating system we consider a pipeline-riser geometry with typical dimensions of offshore oil production systems, and a three-phase flow of oil, gas and water. The model developed in OLGA considers the composition and dimensions of the tubes, heat transfer parameters, process equipment and fluid sources. The fluids properties are calculated using the software PVTsim. Simulations are ran in order to determine the pipeline inner diameter and insulation required to satisfy pressure and temperature requirements. It is also possible to simulate the transient behavior of the system, which allows to evaluate if production instabilities are present. In case instabilities exist, two mitigation alternatives are evaluated: closure of a choke valve before the separator and gas lift. Considering a possible production shutdown, the tubes insulation is calculated in order to avoid hydrate formation. (author)

  18. A comparison of small-area hospitalisation rates, estimated morbidity and hospital access.

    Science.gov (United States)

    Shulman, H; Birkin, M; Clarke, G P

    2015-11-01

    Published data on hospitalisation rates tend to reveal marked spatial variations within a city or region. Such variations may simply reflect corresponding variations in need at the small-area level. However, they might also be a consequence of poorer accessibility to medical facilities for certain communities within the region. To help answer this question it is important to compare these variable hospitalisation rates with small-area estimates of need. This paper first maps hospitalisation rates at the small-area level across the region of Yorkshire in the UK to show the spatial variations present. Then the Health Survey of England is used to explore the characteristics of persons with heart disease, using chi-square and logistic regression analysis. Using the most significant variables from this analysis the authors build a spatial microsimulation model of morbidity for heart disease for the Yorkshire region. We then compare these estimates of need with the patterns of hospitalisation rates seen across the region. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  19. Use of riser tube rotation equipment in the Emlichheim and Landau petroleum mines of Wintershall AG Erdoelwerke; Einsatz von Steigrohrdrehvorrichtungen in den Erdoelfoerderbetrieben Emlichheim und Landau der Wintershall AG Erdoelwerke

    Energy Technology Data Exchange (ETDEWEB)

    Caspari, R. [Wintershall AG Erdoelwerke, Emlichheim (Germany)

    1998-12-31

    Riser tube rotation equipment has been in use in the Emlichheim and Landau petroleum wells since 1994 in order to ensure longer life of the riser tubes. (orig.) [Deutsch] In den von Wintershall operierten Erdoelfoerderbetrieben Emlichheim und Landau werden ca. 90% der Bohrungen mit Gestaengetiefpumpen gefoerdert. Aufgrund der lagerstaettentechnischen Gegebenheiten, der Thermalmassnahmen in Emlichheim und der Infrastruktur der Betriebe koennen andere Foerderhilfsmittel wie Tauchkreiselpumpe, Excenterschneckenpumpe oder Gasliften nur bedingt zum Einsatz kommen. Ein wesentlicher Faktor fuer den wirtschaftlichen Betrieb dieser Bohrungen sind die Aufwaeltigungen zur Beseitigung von Schaeden an der Tiefpumpe, dem Pumpgestaenge und den Steigrohren. Waehrend die Einsatzdauer der Tiefpumpen und des Pumpgestaenges durch hoeherwertige Materialguete und geeignete Optimierungsmassnahmen erhoeht werden konnten, sind die Standzeiten der Steigrohre nahezu unveraendert geblieben. Um diese zu erhoehen, werden in den Erdoelfoerderbetrieben Emlichheim und Landau seit April 1994 Steigrohrdrehvorrichtungen eingesetzt. (orig.)

  20. Effect of flow on corrosion in catenary risers and its corrosion inhibitor performance

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Pedro Altoe; Magalhaes, Alvaro Augusto Oliveira; Silva, Jussara de Mello [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Kang, Cheolho; More, Parimal P. [Det Norske Veritas (DNV), Oslo (Norway)

    2009-07-01

    In oil and gas production, multiphase flow is often encountered and a range of different flow patterns can be experienced in pipelines. The flow regime transition and flow characteristics can be changed with the change of pipeline topography, which affects the corrosion and the performance of corrosion inhibitor in these multiphase pipelines. This paper outlines on the effect of inclination on the flow characteristics and their subsequent effect on corrosion rates. Also, this paper presents on the performance of three candidate corrosion inhibitors under severe slugging conditions at low water cut. For the simulation of offshore flow lines and risers, the experiments were carried out in a 44 m long, 10 cm diameter, three different pipeline inclinations of 0, 3 and 45 degrees. Light condensate oil with a viscosity of 2.5 cP at room temperature was used and water cut was 20%. The results indicated that the baseline corrosion rate in 45 degrees showed higher than other inclinations. Each corrosion inhibitor showed a different inhibitor performance. (author)

  1. A three-dimensional simulation of gas/particle flow and ozone decomposition in the riser of a circulating fluidized bed

    DEFF Research Database (Denmark)

    Hansen, Kim Granly; Solberg, Tron; Hjertager, Bjørn Helge

    2004-01-01

    The isothermal decomposition of ozone has been implemented in the CFD code FLOTRACS-MP-3D. The code is a 3D multiphase computational fluid dynamics code with an Eulerian description of both gas and particle phase. The turbulent motion of the particulate phase is modeled using the kinetic theory...... for granular flow, and the gas phase turbulence is modeled using a Sub-Grid-Scale model, cf. Ibsen et al. (2001). The decomposition reaction is studied in a 3D representation of a 0.254 m i.d. riser, which has been studied experimentally by Ouyang et al. (1993). The authors obtained profiles of ozone...

  2. Financial planning and access to financing in small and mediumsized companies in the Venezuelan manufacturing sector

    Directory of Open Access Journals (Sweden)

    Mary A. Vera-Colina

    2011-12-01

    Full Text Available The relationship between the presence of financial planning and difficulties regarding access to financing in small and medium-sized companies (SMEs in the Venezuelan manufacturing sector is studied. This is an explicative type research work, designed as non-experimental, crosssectional and correlational field work, applied to a sample of 67 SMEs. A questionnaire was applied and a review was made of the relevant literature, to establish the characteristics of the selected variables, according to the high-medium-low measurement for each of the selected indicators. The preliminary results make it possible to affirm that the financial planning variable demonstrates a medium presence in the companies, with medium and low levels of coordination among their components. Average access to financing is classified as low, marked by a medium-high access to credit from suppliers, medium access in reinvestment of profits and medium-low access to bank credit lines. There is also evidence of financing patterns compatible with the Pecking Order Theory. The conclusion is that there is a weak relationship between the characteristics of financial planning and the levels of access to financing, with the inference that the behavior of these variables is determined by a multiplicity of factors.

  3. FACTORS AFFECTING ACCESS TO FINANCE OF SMALL AND MEDIUM ENTERPRISES (SMEs OF BANGLADESH

    Directory of Open Access Journals (Sweden)

    Mohammed CHOWDHURY

    2017-12-01

    Full Text Available This study addresses the issues that impede SMEs of Bangladesh in obtaining finance from the financial institutions. To accomplish our goals we collected data from a sample of 86 SMEs to investigate the problems and suggest policy recommendations. We collected data by directly interviewing the respondents with the help of a questionnaire for self-guidance. We also used secondary data for this purpose. Findings revealed that the size and age of the firms, education and skills of the owners, and unfavorable credit terms such as high interest rates, lack of collateral security, corruption by bank officials etc. are some of the biggest hurdles that SMEs in Bangladesh face in getting loans from financial institutions. The limitation is that the study has included one city in its sample population. A nationwide study where there are SMEs in large numbers could lead to better results for this kind of study. The implication is that small businesses, as opposed to the larger ones, face funding obstacles and are discriminated by the financial institutions in granting loans. Built on current literatures and research on SMEs, specially in regard to their ability to access finance, this study captures the information relating to problems identified by SMEs in having access to finance and suggesting the ways and means needed for strengthening the SMEs access to finance for their expansion and growth.

  4. Measurement of Gas Velocities in the Presence of Solids in the Riser of a Cold Flow Circulating Fluidized Bed

    International Nuclear Information System (INIS)

    Spenik, J.; Ludlow, J.C.; Compston, R.; Breault, R.W.

    2007-01-01

    The local gas velocity and the intensity of the gas turbulence in a gas/solid flow are a required measurement in validating the gas and solids flow structure predicted by computational fluid dynamic (CFD) models in fluid bed and transport reactors. The high concentration and velocities of solids, however, make the use of traditional gas velocity measurement devices such as pitot tubes, hot wire anemometers and other such devices difficult. A method of determining these velocities has been devised at the National Energy Technology Laboratory employing tracer gas. The technique developed measures the time average local axial velocity gas component of a gas/solid flow using an injected tracer gas which induces changes in the heat transfer characteristics of the gas mixture. A small amount of helium is injected upstream a known distance from a self-heated thermistor. The thermistor, protected from the solids by means of a filter, is exposed to gases that are continuously extracted from the flow. Changes in the convective heat transfer characteristics of the gas are indicated by voltage variations across a Wheatstone bridge. When pulsed injections of helium are introduced to the riser flow the change in convective heat transfer coefficient of the gas can be rapidly and accurately determined with this instrument. By knowing the separation distance between the helium injection point and the thermistor extraction location as well as the time delay between injection and detection, the gas velocity can easily be calculated. Variations in the measured gas velocities also allow the turbulence intensity of the gas to be estimated

  5. Status and determinants of small farming households' food security and role of market access in enhancing food security in rural Pakistan.

    Directory of Open Access Journals (Sweden)

    Umar Ijaz Ahmed

    Full Text Available In most of the developing countries, lack of resources and little market accessibility are among the major factors that affect small farming household food security. This study aims to investigate the status of small farming households' food security, and its determinants including the role of market accessibility factors in enhancing food security at household level. In addition, this study also determines the households' perception about different kinds of livelihoods risks. This study is based on a household survey of 576 households conducted through face-to-face interviews using structured interviews in Punjab, Pakistan. Food security status is calculated using dietary intake method. The study findings show that one-fourth of the households are food insecure. The study findings reveal that farm households perceive increase in food prices, crop diseases, lack of irrigation water and increase in health expenses as major livelihood risks. Further, the results of logistic regression show that family size, monthly income, food prices, health expenses and debt are main factors influencing the food security status of rural households. Furthermore, the market accessibility factors (road distance and transportation cost do significantly affect the small farming household food security. The results suggest that local food security can be enhanced by creating off-farm employment opportunities, improved transportation facilities and road infrastructure.

  6. The impact of mobile phones on knowledge access and transfer of small-scale horticultural farmers in Tanzania

    Directory of Open Access Journals (Sweden)

    Krone, Madlen

    2014-09-01

    Full Text Available Agriculture is the main economic activity in Tanzania and the country´s largest employer, providing livelihood for at least 80 % of the economically active population. Many studies have identified key challenges facing the sector for Africa in general – among these lack of access to knowledge. For agricultural producers, access to knowledge is important for an improved productivity and competitiveness. The fast diffusion of information and communication technologies (ICT such as mobile phones across Africa in the last years has resulted in an improved access and transfer of agricultural knowledge. Studies have shown that rural actors like farmers in remote areas even use mobile phones for their farming business. Based on qualitative interviews in the Mwanza Region in northwestern Tanzania, this study aims to identify and categorise the different types of knowledge which are transferred via mobile phones. Our results show that mobile phones enlarge the ability of farmers to access business-relevant knowledge at an increasing spatial scale. However, the effects of the use depend on the type of knowledge and other factors. The results add to existing studies by deepening the understanding of the benefits of ICT on knowledge access and transfer for the context of rural small-scale framers in Tanzania.

  7. An Analytical Network Process on Financial Access of the Small and Medium Enterprise in Sharia Banking in Tasikmalaya City

    Directory of Open Access Journals (Sweden)

    Asep Suryanto

    2015-06-01

    Full Text Available Small and Medium Enterprise (SME is one of the significant roles in national economic development. It is seemly followed by the rise of employment absorbent and equity in income distribution. The capital constraint and the impedance of banking financial access have become the main problem to the Small and Medium entrepreneurs. The objectives of this research are to identify the main factors as problems of Small and Medium Enterprises in having access to the financial institutions, and also to find out the solutions of the research problems. This research uses qualitative approach i.e. Analytic Network Process (ANP. Through applying this method, it is expected to help the researchers in making measurement and synthesis of some factors regarding on the topic analyzed as well as finding the solution for problems faced by the SMEs. The resources of the data is derived from questionnaires and in-depth interview with experts, practitioners, SMEs and regulators which then analyzed by the structure and hierarchy into homogen clusters of the SMEs problems and solutions, measuring into ratio scale and building synthesis. As the result, it becomes clear what factors impeding the financial access of the SMEs to banks. The results of this research show that the difficulties of SMEs in accessing financial support in Islamic financial institutions are internal problems of Islamic banking i.e. lack of financial assistance given to the SMEs, the functions of Islamic banking as business partners for SMEs is not optimal. Whereas the external problems in the SMEs are the disability in meeting the financial requirements asked by Islamic banking that are collateral and business history. The internal solutions are Islamic banking must give business mentoring to SMEs that have received financial supports to minimalize the bad credits level. The external solution is the government must also socialize Islamic financial mechanism to SMEs as part of education efforts.

  8. Impact of Users Identities and Access Conditions on Downlink Performance in Closed Small-Cell Networks

    KAUST Repository

    Radaydeh, Redha

    2015-05-26

    This paper investigates the effect of various operation parameters on the downlink user performance in overlaid small-cell networks. The case study considers closed-access small cells (e.g., femtocells), wherein only active authorized user equipments (UEs) can be served, and each of which is allocated single downlink channel at a time. On the other hand, the macrocell base station can unconditionally serve macrocell UEs that exist inside its coverage space. The available channels can be shared simultaneously in the macrocell network and the femtocell network. Moreover, a channel can be reused only at the macrocell base station. The analysis provides quantitative approaches to model UEs identities, their likelihoods of being active, and their likelihoods of producing interference, considering UEs classifications, locations, and access capabilities. Moreover, it develops models for various interference sources observed from effective interference femtocells, considering femtocells capacities and operation conditions. The associated formulations to describe a desired UE performance and the impact of the number of available channels as well as the adopted channel assignment approach are thoroughly investigated. The results are generally presented for any channel models of interference sources as well as the desired source of the served UE. Moreover, specific channel models are then adopted, for which generalized closedform analytical results for the desired UE outage probability performance are obtained. Numerical and simulation results are presented to further clarify the main outcomes of the developed analysis.

  9. Small States in Europe

    DEFF Research Database (Denmark)

    This book offers an accessible, coherent and informative analysis of contemporary and future foreign policy challenges facing small states in Europe.......This book offers an accessible, coherent and informative analysis of contemporary and future foreign policy challenges facing small states in Europe....

  10. Experimental study of the vortex-induced vibration of drilling risers under the shear flow with the same shear parameter at the different Reynolds numbers.

    Science.gov (United States)

    Liangjie, Mao; Qingyou, Liu; Shouwei, Zhou

    2014-01-01

    A considerable number of studies for VIV under the uniform flow have been performed. However, research on VIV under shear flow is scarce. An experiment for VIV under the shear flow with the same shear parameter at the two different Reynolds numbers was conducted in a deep-water offshore basin. Various measurements were obtained by the fiber bragg grating strain sensors. Experimental data were analyzed by modal analysis method. Results show several valuable features. First, the corresponding maximum order mode of the natural frequency for shedding frequency is the maximum dominant vibration mode and multi-modal phenomenon is appeared in VIV under the shear flow, and multi-modal phenomenon is more apparent at the same shear parameter with an increasing Reynolds number under the shear flow effect. Secondly, the riser vibrates at the natural frequency and the dominant vibration frequency increases for the effect of the real-time tension amplitude under the shear flow and the IL vibration frequency is the similar with the CF vibration frequency at the Reynolds number of 1105 in our experimental condition and the IL dominant frequency is twice the CF dominant frequency with an increasing Reynolds number. In addition, the displacement trajectories at the different locations of the riser appear the same shape and the shape is changed at the same shear parameter with an increasing Reynolds number under the shear flow. The diagonal displacement trajectories are observed at the low Reynolds number and the crescent-shaped displacement trajectories appear with an increasing Reynolds number under shear flow in the experiment.

  11. Experimental study of the vortex-induced vibration of drilling risers under the shear flow with the same shear parameter at the different Reynolds numbers.

    Directory of Open Access Journals (Sweden)

    Mao Liangjie

    Full Text Available A considerable number of studies for VIV under the uniform flow have been performed. However, research on VIV under shear flow is scarce. An experiment for VIV under the shear flow with the same shear parameter at the two different Reynolds numbers was conducted in a deep-water offshore basin. Various measurements were obtained by the fiber bragg grating strain sensors. Experimental data were analyzed by modal analysis method. Results show several valuable features. First, the corresponding maximum order mode of the natural frequency for shedding frequency is the maximum dominant vibration mode and multi-modal phenomenon is appeared in VIV under the shear flow, and multi-modal phenomenon is more apparent at the same shear parameter with an increasing Reynolds number under the shear flow effect. Secondly, the riser vibrates at the natural frequency and the dominant vibration frequency increases for the effect of the real-time tension amplitude under the shear flow and the IL vibration frequency is the similar with the CF vibration frequency at the Reynolds number of 1105 in our experimental condition and the IL dominant frequency is twice the CF dominant frequency with an increasing Reynolds number. In addition, the displacement trajectories at the different locations of the riser appear the same shape and the shape is changed at the same shear parameter with an increasing Reynolds number under the shear flow. The diagonal displacement trajectories are observed at the low Reynolds number and the crescent-shaped displacement trajectories appear with an increasing Reynolds number under shear flow in the experiment.

  12. Modelling of FCC (Fluid Catalytic Cracking) risers with six lumps; Modelo de elevadores de Unidades de Craqueamento Catalitico com cinetica de seis classes

    Energy Technology Data Exchange (ETDEWEB)

    Baldessar, Fabio; Negrao, Cezar O. Ribeiro; Palu, Claudia [Centro Federal de Educacao Tecnologica do Parana (CEFET-PR), Curitiba, PR (Brazil)

    2004-07-01

    The current work presents a mathematical model of an ascendant flow vertical reactor (riser) of a Fluid Catalytic Cracking Unit. The two-phase flow (gas-solid) and the cracking reactions are admitted one-dimensional and steady state. Mass, momentum and energy conservation equations are considered for each phase (solid and gas). A six-lump kinetic model is employed to evaluate gasoil, gasoline, GLP, fuel gas, light cycle oil and coke fractions. The model results are compared to experimental values from a pilot plant and to another model found in the literature. The results are in good agreement, showing the model has great potential. (author)

  13. Scarab III Remote Vehicle Deployment for Waste Retrieval and Tank Inspection

    International Nuclear Information System (INIS)

    Burks, B.L.; Falter, D.D.; Noakes, M.; Vesco, D.

    1999-01-01

    The Robotics Technology Development Program now known as the Robotics Crosscut Program, funded the development and deployment of a small remotely operated vehicle for inspection and cleanout of small horizontal waste storage tanks that have limited access. Besides the advantage of access through tank risers as small as 18-in. diameter, the small robotic system is also significantly less expensive to procure and to operate than larger remotely operated vehicle (ROV) systems. The vehicle specified to support this activity was the ROV Technologies, Inc., Scarab. The Scarab is a tracked vehicle with an independently actuated front and rear ''toe'' degree-of-freedom which allows the stand-off and angle of the vehicle platform with respect to the floor to be changed. The Scarab is a flexible remote tool that can be used for a variety of tasks with its primary uses targeted for inspection and small scale waste retrieval. The vehicle and any necessary process equipment are mounted in a deployment and containment enclosure to simplify deployment and movement of the system from tank to tank. This paper outlines the technical issues related to the Scarab vehicle and its deployment for use in tank inspection and waste retrieval operation

  14. Relationship between human resource ability and market access capacity on business performance. (case study of wood craft micro- and small-scale industries in Gianyar Regency, Bali)

    Science.gov (United States)

    Sukartini, N. W.; Sudarmini, N. M.; Lasmini, N. K.

    2018-01-01

    The aims of this research are to: (1) analyze the influence of Human Resource Ability on market access capacity in Wood Craft Micro and Small Industry; (2) to analyze the effect of market access capacity on business performance; (3) analyze the influence of Human Resources ability on business performance. Data were collected using questionnaires, interviews, observations, and literature studies. The resulting data were analyzed using Struture Equation Modeling (SEM). The results of the analysis show that (1) there is a positive and significant influence of the ability of Human Resources on market access capacity in Wood Craft Micro-and Small-Scale Industries in Gianyar; (2) there is a positive and significant influence of market access capacity on business performance; and (3) there is a positive and significant influence of Human Resource ability on business performance. To improve the ability to access the market and business performance, it is recommended that human resource ability need to be improved through training; government and higher education institutions are expected to play a role in improving the ability of human resources (craftsmen) through provision of training programs

  15. Growth rate correlates negatively with protein turnover in Arabidopsis accessions.

    Science.gov (United States)

    Ishihara, Hirofumi; Moraes, Thiago Alexandre; Pyl, Eva-Theresa; Schulze, Waltraud X; Obata, Toshihiro; Scheffel, André; Fernie, Alisdair R; Sulpice, Ronan; Stitt, Mark

    2017-08-01

    Previous studies with Arabidopsis accessions revealed that biomass correlates negatively to dusk starch content and total protein, and positively to the maximum activities of enzymes in photosynthesis. We hypothesized that large accessions have lower ribosome abundance and lower rates of protein synthesis, and that this is compensated by lower rates of protein degradation. This would increase growth efficiency and allow more investment in photosynthetic machinery. We analysed ribosome abundance and polysome loading in 19 accessions, modelled the rates of protein synthesis and compared them with the observed rate of growth. Large accessions contained less ribosomes than small accessions, due mainly to cytosolic ribosome abundance falling at night in large accessions. The modelled rates of protein synthesis resembled those required for growth in large accessions, but were up to 30% in excess in small accessions. We then employed 13 CO 2 pulse-chase labelling to measure the rates of protein synthesis and degradation in 13 accessions. Small accessions had a slightly higher rate of protein synthesis and much higher rates of protein degradation than large accessions. Protein turnover was negligible in large accessions but equivalent to up to 30% of synthesised protein day -1 in small accessions. We discuss to what extent the decrease in growth in small accessions can be quantitatively explained by known costs of protein turnover and what factors may lead to the altered diurnal dynamics and increase of ribosome abundance in small accessions, and propose that there is a trade-off between protein turnover and maximisation of growth rate. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  16. EVALUACIÓN MICROMAGNÉTICA DEL NIVEL DE TENSIONES EN ALAMBRES DE TRACCIÓN DE RISERS FLEXIBLES

    Directory of Open Access Journals (Sweden)

    JOSÉ MATOS

    2013-01-01

    Full Text Available En el presente trabajo se describe el uso de un método no destructivo que combina las medidas de los parámetros micromagnéticos para cuantificar las tensiones durante los ensayos de tracción en alambres que componen la armadura estructural de risers flexibles. Este método consideró las técnicas de análisis armónico del campo magnético tangencial, análisis de ruido Barkhausen y el análisis del incremento de la permeabilidad, mediante el ensayo de tracción con carga controlada. Se utiliza la regresión lineal de multiparámetros para analizar los datos de cada técnica en forma individual y en conjunto, con el objetivo de correlacionar los valores conocidos de las cargas con los valores medidos en los ensayos realizados. Los resultados muestran una buena relación de los valores obtenidos mediante el método micromagnético y las cargas aplicadas a los cuerpos de prueba, demostrando la eficacia de la técnica en estas aplicaciones.

  17. Virtual Mission Operations Center -Explicit Access to Small Satellites by a Net Enabled User Base

    Science.gov (United States)

    Miller, E.; Medina, O.; Paulsen, P.; Hopkins, J.; Long, C.; Holloman, K.

    2008-08-01

    The Office of Naval Research (ON R), The Office of the Secr etary of Defense (OSD) , Th e Operationally Responsive Space Off ice (ORS) , and th e National Aeronautics and Space Administration (NASA) are funding the development and integration of key technologies and new processes that w ill allow users across th e bread th of operations the ab ility to access, task , retr ieve, and collaborate w ith data from various sensors including small satellites v ia the Intern et and the SIPRnet. The V irtual Mission Oper ations Center (VMO C) facilitates the dynamic apportionmen t of space assets, allows scalable mission man agement of mu ltiple types of sensors, and provid es access for non-space savvy users through an intu itive collaborative w eb site. These key technologies are b eing used as experimentation pathfinders fo r th e Do D's Operationally Responsiv e Sp ace (O RS) initiative and NASA's Sensor W eb. The O RS initiative seeks to provide space assets that can b e rapid ly tailored to meet a commander's in telligen ce or commun ication needs. For the DoD and NASA the V MO C provid es ready and scalab le access to space b ased assets. To the commercial space sector the V MO C may provide an analog to the innovativ e fractional ownersh ip approach represen ted by FlexJet. This pap er delves in to the technology, in tegration, and applicability of th e V MO C to th e DoD , NASA , and co mmer cial sectors.

  18. Adaptive interference-aware multichannel assignment for shared overloaded small-cell access points under limited feedback

    KAUST Repository

    Radaydeh, Redha Mahmoud

    2014-02-01

    This paper proposes a reduced-complexity multichannel assignment scheme for short-range cellular systems. It treats the scenario when a number of small-cell (e.g., femtocell) access points (APs) can be shared to serve active scheduled users. The APs employ isotropic antenna arrays and operate using an open-access control strategy. To improve the reuse ratio of physical resources, the APs are assumed to occupy a single physical channel, wherein coordination among them is infeasible. On the other hand, to improve the spatial coverage, a scheduled user can be served by a single transmit channel from an AP at a time. For the case of overloaded APs and when the feedback links are capacity limited, the scheme attempts to identify the suitable transmit channels from the deployed APs in an adaptive manner such that certain performance and/or processing load limits are satisfied. The effects of some system and design parameters on the outcomes of the scheme are thoroughly discussed. Novel results for the statistics of the resulting interference power are presented, from which results for some performance measures and processing loads are obtained. Numerical and simulations results are provided to clarify the achieved gains, as compared with related models under different operating conditions. © 2013 IEEE.

  19. Small-Scale Irrigation, Farm Income and Access to Essential ...

    African Journals Online (AJOL)

    2017-05-01

    -operated bases, which produce about 80% of total ... opportunities make the income status and access to services such as education, health .... The study revealed that social factors such as belonging to higher caste, poverty.

  20. Improved Interference-Free Channel Allocation in Coordinated Multiuser Multi-Antenna Open-Access Small Cells

    KAUST Repository

    Radaydeh, Redha; Zafar, Ammar; Al-Qahtani, Fawaz; Alouini, Mohamed-Slim

    2016-01-01

    This paper investigates low-complexity joint interference avoidance and desired link improvement for single channel allocation in multiuser multi-antenna access points (APs) for open-access small cells. It is considered that an active user is equipped with an atenna array that can be used to suppress interference sources but not to provide spatial diversity. On the other hand, the operation of APs can be coordinated to meet design requirements, and each of which can unconditionally utilize assigned physical channels. Moreover, each AP is equipped with uncorrelated antennas that can be reused simultaneously to serve many active users. The analysis provides new approaches to exploit physical channels, transmit antennas, and APs to mitigate interference, while providing the best possible link gain to an active user through the most suitable interference-free channel. The event of concurrent service requests placed by active users on a specific interference-free channel is discussed for either interference avoidance through identifying unshared channels or desired link improvement via multiuser scheduling. The applicability of the approaches to balance downlink loads is explained, and practical scenarios due to imperfect identification of interference-free channels and/or scheduled user are thoroughly investigated. The developed results are applicable for any statistical and geometric models of the allocated channel to an active user as well as channel conditions of interference users. They can be used to study various performance measures. Numerical and simulation results are presented to explain some outcomes of this work.

  1. Improved Interference-Free Channel Allocation in Coordinated Multiuser Multi-Antenna Open-Access Small Cells

    KAUST Repository

    Radaydeh, Redha

    2016-02-16

    This paper investigates low-complexity joint interference avoidance and desired link improvement for single channel allocation in multiuser multi-antenna access points (APs) for open-access small cells. It is considered that an active user is equipped with an atenna array that can be used to suppress interference sources but not to provide spatial diversity. On the other hand, the operation of APs can be coordinated to meet design requirements, and each of which can unconditionally utilize assigned physical channels. Moreover, each AP is equipped with uncorrelated antennas that can be reused simultaneously to serve many active users. The analysis provides new approaches to exploit physical channels, transmit antennas, and APs to mitigate interference, while providing the best possible link gain to an active user through the most suitable interference-free channel. The event of concurrent service requests placed by active users on a specific interference-free channel is discussed for either interference avoidance through identifying unshared channels or desired link improvement via multiuser scheduling. The applicability of the approaches to balance downlink loads is explained, and practical scenarios due to imperfect identification of interference-free channels and/or scheduled user are thoroughly investigated. The developed results are applicable for any statistical and geometric models of the allocated channel to an active user as well as channel conditions of interference users. They can be used to study various performance measures. Numerical and simulation results are presented to explain some outcomes of this work.

  2. Big Opportunities in Access to "Small Science" Data

    OpenAIRE

    Onsrud, Harlan; Campbell, James

    2007-01-01

    A distributed infrastructure that would enable those who wish to do so to contribute their scientific or technical data to a universal digital commons could allow such data to be more readily preserved and accessible among disciplinary domains. Five critical issues that must be addressed in developing an efficient and effective data commons infrastructure are described. We conclude that creation of a distributed infrastructure meeting the critical criteria and deployable throughout the networ...

  3. Small-bore-piping seismic-test findings

    International Nuclear Information System (INIS)

    Severud, L.K.; Barta, D.A.; Anderson, M.J.

    1981-12-01

    Description is given of a test series in which a 1-inch diameter stainless steel pipe system was subjected to dynamic testing. The test system consisted of approximately 40-feet of schedule 40 pipe, with several bends and risers, supported from a rigid test frame. FFTF prototypic pipe clamps, dead weight supports, mechanical snubbers, and insulation were utilized. Several variations of the pipe support configuration were tested. Measured test results are compared with analytical predictions for each configuration. Plans for future testing are discussed

  4. Radiographic detection of IGSCC using MINAC

    International Nuclear Information System (INIS)

    Lapides, M.L.

    1984-01-01

    In response to utility interest MINAC, a portable linear accelerator (RP 822) was modified to yield an extremely small accelerator, e.g., radiation source, volume appropriate for BWR riser piping inspection. The modified unit dubbed Shrinkac was shown to be capable of detecting IGSCC of approximately 30% throughwall depth in laboratory tests using water-filled riser pipes. Since the test cracks were tighter than service expectations, it was projected that IGSCC or approximately 15% throughwall depth could be detected in the field. The Shrinkac unit was successfully utilized at Peachbottom Unit 3 to detect both axial and circumferential flaws in riser piping considered to be uninspectable by ultrasonics because of weldment rework conditions. Pipes ranging from 12-20'' nominal size, water-filled and with and without weld overlay remedies were successfully examined

  5. Small scale farmers’ access to and participation in markets : The case of the P4P program in western Kenya

    OpenAIRE

    Skjöldevald, Maja

    2012-01-01

    The purpose of this thesis is to understand how small scale farmers navigate the market to access and participate in the formal maize market to improve their revenue, utilising the case of the P4P program inKenya. The empirical material was collected during fieldwork in Kenya. Qualitative methods were found to be the most suitable for this thesis. The methods that was utilised were a case study strategy, semi structured interviews, focus groups, observations and analysis of secondary sources....

  6. Does small equal predatory? Analysis of publication charges and transparency of editorial policies in Croatian open access journals.

    Science.gov (United States)

    Stojanovski, Jadranka; Marušić, Ana

    2017-06-15

    We approach the problem of "predatory" journals and publishers from the perspective of small scientific communities and small journals that may sometimes be perceived as "predatory". Among other characteristics of "predatory" journals two most relevant are their business model and the quality of the editorial work. We analysed 444 Croatian open access (OA) journals in the Hrčak (portal of Croatian scientific journals) digital journal repository for the presence of article processing charges as a business model and the transparency of editorial policies. The majority of journals do not charge authors or require submission or article processing charges, which clearly distinguishes them from "predatory" journals. Almost all Hrčak OA journals have publicly available information on editorial boards, including full names and affiliations, and detailed contact information for the editorial office at the Hrčak website. The journal names are unique and cannot be easily confused with another journal or intend to mislead about the journal's origin. While most journals provide information on peer review process, many do not provide guidelines for reviewers or other editorial and publication ethics standards. In order to clearly differentiate themselves from predatory journals, it is not enough for journals from small research communities to operate on non-commercial bases, but also to have transparent editorial policies.

  7. Performance of Overlaid MIMO Cellular Networks with TAS/MRC under Hybrid-Access Small Cells and Poisson Field Interference

    KAUST Repository

    AbdelNabi, Amr A.

    2018-02-12

    This paper presents new approaches to characterize the achieved performance of hybrid control-access small cells in the context of two-tier multi-input multi-output (MIMO) cellular networks with random interference distributions. The hybrid scheme at small cells (such as femtocells) allows for sharing radio resources between the two network tiers according to the densities of small cells and their associated users, as well as the observed interference power levels in the two network tiers. The analysis considers MIMO transceivers at all nodes, for which antenna arrays can be utilized to implement transmit antenna selection (TAS) and receive maximal ratio combining (MRC) under MIMO point-to-point channels. Moreover, it tar-gets network-level models of interference sources inside each tier and between the two tiers, which are assumed to follow Poisson field processes. To fully capture the occasions for Poisson field distribution on MIMO spatial domain. Two practical scenarios of interference sources are addressed including highly-correlated or uncorrelated transmit antenna arrays of the serving macrocell base station. The analysis presents new analytical approaches that can characterize the downlink outage probability performance in any tier. Furthermore, the outage performance in high signal-to-noise (SNR) regime is also obtained, which can be useful to deduce diversity and/or coding gains.

  8. Performance of Overlaid MIMO Cellular Networks with TAS/MRC under Hybrid-Access Small Cells and Poisson Field Interference

    KAUST Repository

    AbdelNabi, Amr A.; Al-Qahtani, Fawaz S.; Radaydeh, Redha Mahmoud Mesleh; Shaqfeh, Mohammad; Manna, Raed F.

    2018-01-01

    This paper presents new approaches to characterize the achieved performance of hybrid control-access small cells in the context of two-tier multi-input multi-output (MIMO) cellular networks with random interference distributions. The hybrid scheme at small cells (such as femtocells) allows for sharing radio resources between the two network tiers according to the densities of small cells and their associated users, as well as the observed interference power levels in the two network tiers. The analysis considers MIMO transceivers at all nodes, for which antenna arrays can be utilized to implement transmit antenna selection (TAS) and receive maximal ratio combining (MRC) under MIMO point-to-point channels. Moreover, it tar-gets network-level models of interference sources inside each tier and between the two tiers, which are assumed to follow Poisson field processes. To fully capture the occasions for Poisson field distribution on MIMO spatial domain. Two practical scenarios of interference sources are addressed including highly-correlated or uncorrelated transmit antenna arrays of the serving macrocell base station. The analysis presents new analytical approaches that can characterize the downlink outage probability performance in any tier. Furthermore, the outage performance in high signal-to-noise (SNR) regime is also obtained, which can be useful to deduce diversity and/or coding gains.

  9. Small World: Access to Higher Education between Methodological Nationalism and International Organisations

    Science.gov (United States)

    Goastellec, Gaele

    2010-01-01

    What do the shared norms emerging in the regulation of access reveal about the higher education internationalisation process? The history of access norms brings to light two characteristics of this process: the spreading of sociotechnic tools and the emergence of moral entrepreneurs. Based on case studies carried out in France, the US, South…

  10. SWEEP Project RAT

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Madsen, Søren; Petersen, L. B.

    This report presents the results from the design analyses made for the clustered suction caisson used as foundation for a Riser Access Tower (RAT). The RAT is intended built next to the K15-FA-1 Platform in the Dutch Sector of the North Sea....

  11. Average opportunity-based accessibility of public transit systems to grocery stores in small urban areas

    Directory of Open Access Journals (Sweden)

    Nimish Dharmadhikari

    2015-12-01

    Full Text Available This research studies the accessibility of grocery stores to university students using the public transportation system, drawing from a case study of Fargo, North Dakota. Taking into consideration the combined travel time components of walking, riding, and waiting, this study measures two types of accessibilities: accessibility to reach a particular place and accessibility to reach the bus stop to ride the public transit system. These two accessibilities are interdependent and cannot perform without each other. A new method to calculate the average accessibility measure for the transit routes is proposed. A step-wise case study analysis indicates that one route provides accessibility to a grocery store in eight minutes. This also suggests that the North Dakota State University area has moderate accessibility to grocery stores.

  12. Small Molecules Modulate Chromatin Accessibility to Promote NEUROG2-Mediated Fibroblast-to-Neuron Reprogramming

    Directory of Open Access Journals (Sweden)

    Derek K. Smith

    2016-11-01

    Full Text Available Pro-neural transcription factors and small molecules can induce the reprogramming of fibroblasts into functional neurons; however, the immediate-early molecular events that catalyze this conversion have not been well defined. We previously demonstrated that neurogenin 2 (NEUROG2, forskolin (F, and dorsomorphin (D can reprogram fibroblasts into functional neurons with high efficiency. Here, we used this model to define the genetic and epigenetic events that initiate an acquisition of neuronal identity. We demonstrate that NEUROG2 is a pioneer factor, FD enhances chromatin accessibility and H3K27 acetylation, and synergistic transcription activated by these factors is essential to successful reprogramming. CREB1 promotes neuron survival and acts with NEUROG2 to upregulate SOX4, which co-activates NEUROD1 and NEUROD4. In addition, SOX4 targets SWI/SNF subunits and SOX4 knockdown results in extensive loss of open chromatin and abolishes reprogramming. Applying these insights, adult human glioblastoma cell and skin fibroblast reprogramming can be improved using SOX4 or chromatin-modifying chemicals.

  13. Numerical Investigation of Hydrodynamic Instabilities in Singing Risers Investigation numérique des instabilités hydrodynamiques de risers chantants

    Directory of Open Access Journals (Sweden)

    Brac J.

    2012-09-01

    Full Text Available Offshore transportation of gaseous fluids frequently relies on flexible pipes. Flexible pipes are obtained from the helicoidal rolling of steel tape which induces a geometrical cavity from edge to edge. Along the pipe, the gas infinitely encounters the edge to edge cavity of the same shape at regular interval. In some service conditions, acoustic vibrations of huge amplitude can arise. Indeed, in front of each cavity, there is a shear layer where Kelvin-Helmholtz instability can occur. The flow encounters a large number of cavities on its path which gives rise to a new specific problem: is there a stabilized flow? Results of large eddy scale simulations are presented as a reference but they are very costly. This gives reason to develop a numerical solution of the Orr-Sommerfeld equation in order to analyze the temporal and spatial wave lengths generated by the shear layers in front of the cavities. First, we introduce the problem of flexible risers and the analysis of some RANS and LES modeling. Second, a bibliographical study describes the state of the art about vibrations induced by cavity. Third, we state the Orr-Sommerfeld equation and set the problem we want to solve in terms of generalized eigen values Numerical discretizations are based on finite difference approaches of fourth orders. The choice of the relevant eigen values among all those provided by the solutions of the numerical problem is the main difficulty to be tackled. Le transport offshore de gaz utilise souvent des conduites flexibles. Elles sont fabriquées en enroulant en hélice un ruban d’acier; au contact bord à bord des tours d’hélice, une cavité apparaît. Le gaz s’écoule en conduite et rencontre cette cavité à intervalles réguliers, toujours avec la même forme. Dans certaines conditions d’usage, des vibrations acoustiques de grandes amplitudes apparaissent. En effet, devant chaque cavité, il y a une couche de cisaillement où une instabilité de type

  14. Is small beautiful? Financial structure, size and access to finance

    NARCIS (Netherlands)

    Beck, T.H.L.; Demirgüc-Kunt, A.; Singer, D.E.M.

    2013-01-01

    Combining two unique data sets, this paper explores the relationship between financial structure and firms’ access to financial services. Specifically, it considers the importance of three different types of financial institutions: low-end financial institutions, specialized lenders, and banks. Two

  15. How will a credit crunch affect small business finance?

    OpenAIRE

    Gregory F. Udell

    2009-01-01

    This Economic Letter explores how the credit crunch might affect small business access to finance. While it is not possible to know how severe this credit crunch will become, researchers can explore how the crunch could affect small business finance. We begin our analysis by looking at how small businesses access external sources of finance. Then we consider how these sources might be affected by the crunch.

  16. Notified Access: Extending Remote Memory Access Programming Models for Producer-Consumer Synchronization

    KAUST Repository

    Belli, Roberto; Hoefler, Torsten

    2015-01-01

    Remote Memory Access (RMA) programming enables direct access to low-level hardware features to achieve high performance for distributed-memory programs. However, the design of RMA programming schemes focuses on the memory access and less on the synchronization. For example, in contemporary RMA programming systems, the widely used producer-consumer pattern can only be implemented inefficiently, incurring in an overhead of an additional round-trip message. We propose Notified Access, a scheme where the target process of an access can receive a completion notification. This scheme enables direct and efficient synchronization with a minimum number of messages. We implement our scheme in an open source MPI-3 RMA library and demonstrate lower overheads (two cache misses) than other point-to-point synchronization mechanisms for each notification. We also evaluate our implementation on three real-world benchmarks, a stencil computation, a tree computation, and a Colicky factorization implemented with tasks. Our scheme always performs better than traditional message passing and other existing RMA synchronization schemes, providing up to 50% speedup on small messages. Our analysis shows that Notified Access is a valuable primitive for any RMA system. Furthermore, we provide guidance for the design of low-level network interfaces to support Notified Access efficiently.

  17. Notified Access: Extending Remote Memory Access Programming Models for Producer-Consumer Synchronization

    KAUST Repository

    Belli, Roberto

    2015-05-01

    Remote Memory Access (RMA) programming enables direct access to low-level hardware features to achieve high performance for distributed-memory programs. However, the design of RMA programming schemes focuses on the memory access and less on the synchronization. For example, in contemporary RMA programming systems, the widely used producer-consumer pattern can only be implemented inefficiently, incurring in an overhead of an additional round-trip message. We propose Notified Access, a scheme where the target process of an access can receive a completion notification. This scheme enables direct and efficient synchronization with a minimum number of messages. We implement our scheme in an open source MPI-3 RMA library and demonstrate lower overheads (two cache misses) than other point-to-point synchronization mechanisms for each notification. We also evaluate our implementation on three real-world benchmarks, a stencil computation, a tree computation, and a Colicky factorization implemented with tasks. Our scheme always performs better than traditional message passing and other existing RMA synchronization schemes, providing up to 50% speedup on small messages. Our analysis shows that Notified Access is a valuable primitive for any RMA system. Furthermore, we provide guidance for the design of low-level network interfaces to support Notified Access efficiently.

  18. The Small Payload Access to Space Experiment (SPASE): Using Non-Traditional Aerospace Technology to Enable a New Generation of Low-Cost Missions

    OpenAIRE

    McDermott, Scott; Aamot, L. Eric

    2001-01-01

    Launching on STS-108 Endeavour in late 2001, the Small Payload Access to Space Experiment (SPASE) demonstrates a number of new technologies, efficient ways to conduct a nanospacecraft development program, and how to take such a spacecraft through the Shuttle Hitchhiker safety and integration process. This paper describes the essential “lessons learned” in each of these areas. Commercial solar panels, batteries, imagers, photocells, integrated circuits, and manufacturing techniques are used th...

  19. An Analytical Method for Jack-Up Riser’s Fatigue Life Estimation

    Directory of Open Access Journals (Sweden)

    Fengde Wang

    2018-01-01

    Full Text Available In order to determine whether a special sea area and its sea state are available for the jack-up riser with surface blowout preventers, an analytical method is presented to estimate the jack-up riser’s wave loading fatigue life in this study. In addition, an approximate formula is derived to compute the random wave force spectrum of the small-scale structures. The results show that the response of jack-up riser is a narrow band random vibration. The infinite water depth dispersion relation between wavenumber and wave frequency can be used to calculate the wave force spectrum of small-scale structures. The riser’s response mainly consists of the additional displacement response. The fatigue life obtained by the formula proposed by Steinberg is less than that of the Bendat method.

  20. Mutual Guarantee Institutions and Small Business Finance

    NARCIS (Netherlands)

    Columba, F.; Gambacorta, L.; Mistrulli, P.E.

    2009-01-01

    A large literature showed that small firms experience difficulties in accessing the credit market due to informational asymmetries; these may be mitigated by collateral or relationship lending, possibilities often precluded to small business. We investigate the effect on small business finance of an

  1. Addressing geographic access barriers to emergency care services: a national ecologic study of hospitals in Brazil.

    Science.gov (United States)

    Rocha, Thiago Augusto Hernandes; da Silva, Núbia Cristina; Amaral, Pedro Vasconcelos; Barbosa, Allan Claudius Queiroz; Rocha, João Victor Muniz; Alvares, Viviane; de Almeida, Dante Grapiuna; Thumé, Elaine; Thomaz, Erika Bárbara Abreu Fonseca; de Sousa Queiroz, Rejane Christine; de Souza, Marta Rovery; Lein, Adriana; Lopes, Daniel Paulino; Staton, Catherine A; Vissoci, João Ricardo Nickenig; Facchini, Luiz Augusto

    2017-08-22

    Unequal distribution of emergency care services is a critical barrier to be overcome to assure access to emergency and surgical care. Considering this context it was objective of the present work analyze geographic access barriers to emergency care services in Brazil. A secondary aim of the study is to define possible roles to be assumed by small hospitals in the Brazilian healthcare network to overcome geographic access challenges. The present work can be classified as a cross-sectional ecological study. To carry out the present study, data of all 5843 Brazilian hospitals were categorized among high complexity centers and small hospitals. The geographical access barriers were identified through the use of two-step floating catchment area method. Once concluded the previous step an evaluation using the Getis-Ord-Gi method was performed to identify spatial clusters of municipalities with limited access to high complexity centers but well covered by well-equipped small hospitals. The analysis of accessibility index of high complexity centers highlighted large portions of the country with nearly zero hospital beds by inhabitant. In contrast, it was possible observe a group of 1595 municipalities with high accessibility to small hospitals, simultaneously with a low coverage of high complexity centers. Among the 1595 municipalities with good accessibility to small hospitals, 74% (1183) were covered by small hospitals with at least 60% of minimum emergency service requirements. The spatial clusters analysis aggregated 589 municipalities with high values related to minimum emergency service requirements. Small hospitals in these 589 cities could promote the equity in access to emergency services benefiting more than eight million people. There is a spatial disequilibrium within the country with prominent gaps in the health care network for emergency services. Taking this challenge into consideration, small hospitals could be a possible solution and foster equity in access

  2. Improving market access opportunities for urban small, medium and micro-enterprises in South Africa

    Directory of Open Access Journals (Sweden)

    Christian M. Rogerson

    2013-01-01

    Full Text Available Since the democratic transition of 1994, the promotion of the small, medium and micro-enterprise (SMME economy has been a core focus of South African government policy. With high levels of unemployment and poverty in urban areas, the impact of this policy intervention is most critical for city development. Given South Africa’s chequered history, the national government’s focus is on transforming the prospects for enterprises owned by black South Africans, who were disadvantaged under apartheid. This article examines the range of contemporary policy initiatives to address business constraints on market access and catalyse new market opportunities for black-owned enterprises in urban South Africa. The article concentrates on two themes: 1 building links into private sector supply chains, especially through supplier diversity, and 2 building links into public sector markets through public procurement. It is shown that current policy directions recognise that the national government has a limited capacity to implement SMME improvement and build competitive black-owned SMMEs by itself, which has prompted support for private sector initiatives. In addition, the government is struggling to practice what it preaches and use its own procurement capacity to assist black-owned SMMEs.

  3. Stress and Pore Pressure Measurement in IODP Riser Drilling: An Example from Expedition 319, Kumano Basin offshore SW Honshu, Japan

    Science.gov (United States)

    Saffer, D. M.; McNeill, L. C.; Byrne, T. B.; Araki, E.; Flemings, P. B.; Conin, M.; Eguchi, N. O.; Takahashi, K.; Toczko, S.; Boutt, D. F.; Doan, M.; Kano, Y.; Ito, T.; Lin, W.

    2009-12-01

    In summer 2009, Integrated Ocean Drilling Program (IODP) Expedition 319 drilled a 1600 m deep riser borehole (Site C0009) in the Kumano Basin offshore SW Japan, to investigate the properties, structure and state of stress in the hanging wall above the subduction plate boundary. The first riser-based scientific drilling in IODP history allowed us to make several new scientific measurements including in situ stress magnitude, pore pressure and permeability using the Modular Formation Dynamics Tester (MDT) wireline tool, and measurement of minimum stress magnitude from Leak-off Tests (LOT). In addition, continuous monitoring of mud weight, mud gas, annular pressure, and mud losses provided data to constrain formation pore fluid pressure and stress. At Site C0009, we conducted 2 LOTs below a casing shoe at 708.6 m depth and 11 successful MDT measurements, including 9 single probe tests to measure pore pressure and fluid mobility and 2 dual packer tests: 1 to measure permeability by a drawdown test, and 1 to measure in situ stress. Measured pore pressures are approximately hydrostatic to 1463.7 m depth. We observed only minor gas shows when drilling ahead (as in-place methane was liberated from the rock at the bit) but little or no gas during pipe connections. This indicates that the borehole mud pressure exceeded the formation pore pressure, and is consistent with the MDT measurements. Permeabilities range from ~10-16 m2 - 10-14 m2, and the observed variation is consistent with lithologic changes defined in gamma ray logs. The MDT measurement at 874.3 mbsf and the LOT at 708.6 m yield values for the least principal stress of 34.8 MPa and 30.2 MPa, respectively. Both are less than the vertical stress (Sv) computed from density logs. Partial mud circulation losses occurred when the borehole mud pressure exceeded the leak-off stress measured at the base of the casing shoe; this provides an additional indirect constraint on Shmin magnitude. Mud pressure slightly in excess

  4. Two-year outcomes of the Early Risers prevention trial with formerly homeless families residing in supportive housing.

    Science.gov (United States)

    Gewirtz, Abigail H; DeGarmo, David S; Lee, Susanne; Morrell, Nicole; August, Gerald

    2015-04-01

    This article reports 2-year outcomes from a cluster randomized, controlled trial of the Early Risers (ER) program implemented as a selective preventive intervention in supportive housing settings for homeless families. Based on the goals of this comprehensive prevention program, we predicted that intervention participants receiving ER services would show improvement in parenting and child outcomes relative to families in treatment-as-usual sites. The sample included 270 children in 161 families, residing in 15 supportive housing sites; multimethod, multi-informant assessments conducted at baseline and yearly thereafter included parent and teacher report of child adjustment, parent report of parenting self-efficacy, and parent-child observations that yielded scores of effective parenting practices. Data were modeled in HLM7 (4-level model accounting for nesting of children within families and families within housing sites). Two years' postbaseline, intent-to-treat (ITT) analyses indicated that parents in the ER group showed significantly improved parenting self-efficacy, and parent report indicated significant reductions in ER group children's depression. No main effects of ITT were shown for observed parenting effectiveness. However, over time, average levels of parenting self-efficacy predicted observed effective parenting practices, and observed effective parenting practices predicted improvements in both teacher- and parent-report of child adjustment. This is the first study to our knowledge to demonstrate prevention effects of a program for homeless families residing in family supportive housing. (c) 2015 APA, all rights reserved).

  5. Innovative approach for low-cost quick-access small payload missions

    Science.gov (United States)

    Friis, Jan W., Jr.

    2000-11-01

    A significant part of the burgeoning commercial space industry is placing an unprecedented number of satellites into low earth orbit for a variety of new applications and services. By some estimates the commercial space industry now exceeds that of government space activities. Yet the two markets remain largely separate, with each deploying dedicated satellites and infrastructure for their respective missions. One commercial space firm, Final Analysis, has created a new program wherein either government, scientific or new technology payloads can be integrated on a commercial spacecraft on commercial satellites for a variety of mission scenarios at a fraction of the cost of a dedicated mission. NASA has recognized the advantage of this approach, and has awarded the Quick Ride program to provide frequent, low cost flight opportunities for small independent payloads aboard the Final Analysis constellation, and investigators are rapidly developing science programs that conform to the proposed payload accommodations envelope. Missions that were not feasible using dedicated launches are now receiving approval under the lower cost Quick Ride approach. Final Analysis has dedicated ten out of its thirty-eight satellites in support of the Quick Ride efforts. The benefit of this type of space access extend beyond NASA science programs. Commercial space firms can now gain valuable flight heritage for new technology and satellite product offerings. Further, emerging international space programs can now place a payload in orbit enabling the country to allocate its resources against the payload and mission requirements rather htan increased launch costs of a dedicated spacecraft. Finally, the low cost nature provides University-based research educational opportunities previously out of the reach of most space-related budgets. This paper will describe the motivation, benefits, technical features, and program costs of the Final Analysis secondary payload program. Payloads can be

  6. Understanding the political economy and key drivers of energy access in addressing national energy access priorities and policies: African Perspective

    International Nuclear Information System (INIS)

    Khennas, Smail

    2012-01-01

    This paper is focused on the key drivers of energy access in North and sub-Saharan Africa which are characterized by huge discrepancies in terms of energy access to modern forms of energy. The paper points out that long term development strategies and large programmes with significant financial resources are essential to achieving substantial results in terms of energy access. The paper argues that building up the energy infrastructure (power plants, grid interconnections and small-scale decentralized energy options in rural areas.) is a pre-condition for economic growth and ultimately for energy access. It underlines that historically there is a trend towards more efficient, convenient and cost effective forms of energy. Low carbon path and above all renewable will therefore play an increasing role in the energy mix in the next couple of decades. Manufacturing of capital goods for the renewable energy industry in Africa will be a key challenge to achieving energy security economic growth and energy access. - Highlights: ► Sharp differences of energy access situation and approaches between North and Sub Saharan Africa. ► Energy infrastructure is a pre-condition to economic growth and energy access. ► Interconnections and small-scale decentralized energy schemes are a good mechanism to increasing energy access. ► However interconnections will only contribute marginally to the urban-rural energy divide. ► Manufacturing of capital goods is a key challenge to economic development.

  7. Equipment and techniques for remote sampling of stored radioactive waste

    International Nuclear Information System (INIS)

    Nance, T.A.

    1996-01-01

    Several tools have been developed at the Savannah River Site (SRS) to remotely sample stored radioactive waste. These sampling tools have been developed to determine the chemical characteristics of the waste prior to processing. The processing of waste material varies according to the chemical characteristics of the waste, which change due to additions, settling, mixing, and chemical reactions during storage. Once the waste has been sampled to identify its characteristics, the chemical composition of the waste can then be altered if needed to prepare for processing. Various types of waste material in several types of containment must be sampled at SRS. Stored waste materials consist of liquids, floating organics, sludge, salt and solids. Waste is stored in four basic types of tanks with different means of access and interior obstructions. The waste tanks can only be accessed by small openings: access ports, risers and downcomers. Requirements for sampling depend on the type of tank being accessed, the waste within the tank, and the particular location in the tank desired for taking the sample. Sampling devices have been developed to sample all of the waste material forms found in the SRS tank farms. The fluid type samplers are capable of sampling surface liquid, subsurface liquid at varying depth, surface sludge, subsurface sludge, and floating organics. The solid type samplers are capable of sampling salt, sampling a solid layer on the bottom of the tank, and capturing a small solid mass on the tank bottom. The sampling devices are all designed to access the tanks through small access ports. The samplers are reusable and are designed to allow quick transfer of the samples to shielded packaging for transport, reducing the amount of radiation exposure to sampling personnel. The samplers weigh less than 100 lb. and are designed in sections to allow easy disassembly for storage and transport by personnel. (Abstract Truncated)

  8. Access to realization of small hydroelectric power station in Republic of Macedonia

    International Nuclear Information System (INIS)

    Jakimova Filipovska, Nevenka

    2001-01-01

    In the paper an overview of the small-scale hydroelectric power plants is presented. The categorization groups of small to micro hydroelectric power plants by different countries are given. Also, the evaluation models of the projects for realization the small hydroelectric power plants are analysed. The aim of the paper is to stress the advantages of the small hydro projects and their implementation in Macedonia

  9. A analytical comparison of different estimators for the density distribution of the catalyst in a experimental riser by a gammametric technique

    International Nuclear Information System (INIS)

    Lima, Emerson Alexandre de Oliveira; Dantas Carlos C.; Melo, Silvio de Barros; Santos, Valdemir Alexandre dos

    2005-01-01

    In this paper, we solve the following questions: what will be the estimate of the r = r (x, y, z) function format? Which method would describe the density distribution function more precisely? Which is the best estimator? Also, once the ρ=ρ(x, y, z) format and the approximation technique is defined, comes the experimental arrangement and pass length configuration, which are the next problems to be solved. Finding the best parameter estimation for the ρ=ρ(x, y, z) function according to the C pass lengths and their spatial configuration. The latter is required to define the ρ=ρ(x, y, z) function resolution and the mechanical scanning movements of the arrangement. Such definitions will be implemented for an automate arrangement, by a computational program, to further development of the reconstruction of catalyst density distribution on experimental risers.. The precision evaluation was finally compared to the arrangement geometry that yields the best pass length spatial configuration. The results are shown in graphics for the two known density distributions. As a conclusion, the parameters for an automate arrangement design, are given under the required precision for the catalyst distribution reconstruction. (author)

  10. Video Game Accessibility: A Legal Approach

    Directory of Open Access Journals (Sweden)

    George Powers

    2015-02-01

    Full Text Available Video game accessibility may not seem of significance to some, and it may sound trivial to anyone who does not play video games. This assumption is false. With the digitalization of our culture, video games are an ever increasing part of our life. They contribute to peer to peer interactions, education, music and the arts. A video game can be created by hundreds of musicians and artists, and they can have production budgets that exceed modern blockbuster films. Inaccessible video games are analogous to movie theaters without closed captioning or accessible facilities. The movement to have accessible video games is small, unorganized and misdirected. Just like the other battles to make society accessible were accomplished through legislation and law, the battle for video game accessibility must be focused toward the law and not the market.

  11. Standard Deviation for Small Samples

    Science.gov (United States)

    Joarder, Anwar H.; Latif, Raja M.

    2006-01-01

    Neater representations for variance are given for small sample sizes, especially for 3 and 4. With these representations, variance can be calculated without a calculator if sample sizes are small and observations are integers, and an upper bound for the standard deviation is immediate. Accessible proofs of lower and upper bounds are presented for…

  12. FDI in small accession countries: The Baltic states

    OpenAIRE

    Hunya, Gábor

    2004-01-01

    Analysing the evolution and determinants of foreign direct investment (FDI) in Estonia, Latvia and Lithuania, this paper argues that sound economic policies have created an environment conducive for FDI. Overall, FDI has contributed to economic growth in the Baltic economies, having financed around one-fifth of fixed investment. However, their small size makes the Baltic countries relatively less attractive for market-seeking FDI in manufacturing. Moreover, at the outset of transition, their ...

  13. An electron-deficient small molecule accessible from sustainable synthesis and building blocks for use as a fullerene alternative in organic photovoltaics.

    Science.gov (United States)

    McAfee, Seth M; Topple, Jessica M; Payne, Abby-Jo; Sun, Jon-Paul; Hill, Ian G; Welch, Gregory C

    2015-04-27

    An electron-deficient small molecule accessible from sustainable isoindigo and phthalimide building blocks was synthesized via optimized synthetic procedures that incorporate microwave-assisted synthesis and a heterogeneous catalyst for Suzuki coupling, and direct heteroarylation carbon-carbon bond forming reactions. The material was designed as a non-fullerene acceptor with the help of DFT calculations and characterized by optical, electronic, and thermal analysis. Further investigation of the material revealed a differing solid-state morphology with the use of three well-known processing conditions: thermal annealing, solvent vapor annealing and small volume fractions of 1,8-diiodooctane (DIO) additive. These unique morphologies persist in the active layer blends and have demonstrated a distinct influence on device performance. Organic photovoltaic-bulk heterojunction (OPV-BHJ) devices show an inherently high open circuit voltage (Voc ) with the best power conversion efficiency (PCE) cells reaching 1.0 V with 0.4 v/v % DIO as a processing additive. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Core disruptive accident margin seal

    International Nuclear Information System (INIS)

    Garin, J.; Belsick, J.C.

    1978-01-01

    Disclosed is an apparatus for sealing the annulus defined between a substantially cylindrical rotatable first riser assembly and plug combination disposed in a substantially cylindrical second riser assembly and plug combination of a nuclear reactor system. The apparatus comprises a flexible member disposed between the first and second riser components and attached to a metal member which is attached to an actuating mechanism. When the actuating mechanism is not actuated, the flexible member does not contact the riser components thus allowing the free rotation of the riser components. When desired, the actuating mechanism causes the flexible member to contact the first and second riser components in a manner to block the annulus defined between the riser components, thereby sealing the annulus between the riser components

  15. Small x physics

    International Nuclear Information System (INIS)

    Kwiecinski, J.

    1993-01-01

    The QCD expectations concerning the small x limit of parton distributions where x is the Bjorken scaling variable are reviewed. This includes discussion of the evolutions equations in the small x region, the Lipatov equation which sums the leading powers of ln(1/x) and the shadowing effects. Phenomenological implantations of the theoretical expectations for the deep inelastic lepton-hadron scattering in the small x region which will be accessible at the HERA ep collider are described. We give predictions for structure functions F 2 and F L and discuss specific processes sensitive to the small x physics such as heavy quark production, deep inelastic diffraction and jet production in deep inelastic lepton scattering. A brief review of nuclear shadowing in the inelastic lepton nucleus scattering at small x is also presented. (author). 86 refs, 29 figs

  16. A modified multi-objective particle swarm optimization approach and its application to the design of a deepwater composite riser

    Science.gov (United States)

    Zheng, Y.; Chen, J.

    2017-09-01

    A modified multi-objective particle swarm optimization method is proposed for obtaining Pareto-optimal solutions effectively. Different from traditional multi-objective particle swarm optimization methods, Kriging meta-models and the trapezoid index are introduced and integrated with the traditional one. Kriging meta-models are built to match expensive or black-box functions. By applying Kriging meta-models, function evaluation numbers are decreased and the boundary Pareto-optimal solutions are identified rapidly. For bi-objective optimization problems, the trapezoid index is calculated as the sum of the trapezoid's area formed by the Pareto-optimal solutions and one objective axis. It can serve as a measure whether the Pareto-optimal solutions converge to the Pareto front. Illustrative examples indicate that to obtain Pareto-optimal solutions, the method proposed needs fewer function evaluations than the traditional multi-objective particle swarm optimization method and the non-dominated sorting genetic algorithm II method, and both the accuracy and the computational efficiency are improved. The proposed method is also applied to the design of a deepwater composite riser example in which the structural performances are calculated by numerical analysis. The design aim was to enhance the tension strength and minimize the cost. Under the buckling constraint, the optimal trade-off of tensile strength and material volume is obtained. The results demonstrated that the proposed method can effectively deal with multi-objective optimizations with black-box functions.

  17. Multiphase flow dynamics and control; Dynamique et controle des ecoulements polyphasiques

    Energy Technology Data Exchange (ETDEWEB)

    Duret, E.

    2005-02-01

    Production in the petroleum industry requires a better knowledge of multiphase flow, as the design of pipelines may cause the flow to become strongly unstable. For instance, for low flow rates and when a sea line ends at a riser, the riser base may accumulate liquid and stop the flow of gas. Then, the upstream gas is compressed until its pressure is large enough to push the liquid slug downstream. Under such conditions, a cyclic process occurs which is called severe slugging, generating large and fast fluctuations in pressure and flow rates. This thesis is devoted to two methods to stabilize this undesirable phenomenon. Using the pipeline's ability to separate phases to pick-up the gas upstream the riser base, they are mainly based on the perturbation theory (fast proportional effect, slow integral effect). The first one uses a secondary riser to transport the gas to the surface facilities. A stability study worked out with the phase diagrams technique shows that it is a good method to control this phenomenon. However, it imposes a high pressure in all the system. Thus, the second controller re-injects the gas at a determined height in the riser to decrease the hydrostatic pressure. A first stability study in open loop give a criterion on the minimal reinjection height. Then, the controller is developed by using the two-time scale control techniques. Finally, let us denote that these two controllers have been validated with a small size experimental set up. (author)

  18. Modeling Of A Fluid Catalytic Cracking (Fcc) Riser Reactor - The ...

    African Journals Online (AJOL)

    Journal of Modeling, Design and Management of Engineering Systems. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 1, No 1 (2002) >. Log in or Register to get access to full text downloads.

  19. Does Access Trump Ownership? Exploring Consumer Acceptance of Access-Based Consumption in the Case of Smartphones

    Directory of Open Access Journals (Sweden)

    Flora Poppelaars

    2018-06-01

    Full Text Available Value creation in a circular economy is based on products being returned after use. In the case of smartphones, most are never returned and tend to be kept in drawers. Smartphone access services (e.g., leasing or upgrade have been experimented with in the Netherlands but have been largely unsuccessful. This study explores the reasons why consumers rejected these access-based smartphone services and is one of the very few to address this topic. The findings are compared with the case of car access services, which are socially better accepted, to identify potential areas for improvement. The qualitative study consists of in-depth interviews with consumers (n = 18 who either adopted and used a smartphone or car access service, or had considered a new smartphone or car but did not choose access-based consumption. The findings of this small-scale study suggest that the main reasons for the rejection of smartphone access services are a lack of awareness, misunderstanding of terms and conditions, and unsatisfactory compensation for their sacrifice of not owning. Smartphone access providers could thus clearly communicate customers’ rights and responsibilities, offer an excellent service experience (especially during repair by taking over the burdens of ownership, and stimulate the societal logic shift from ownership to access.

  20. Optical Access Networks

    Science.gov (United States)

    Zheng, Jun; Ansari, Nirwan

    2005-06-01

    Call for Papers: Optical Access Networks With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the economic viability of many potential high-bandwidth applications. In recent years, optical access networks have been receiving tremendous attention from both academia and industry. A large number of research activities have been carried out or

  1. Distributed Storage Algorithm for Geospatial Image Data Based on Data Access Patterns.

    Directory of Open Access Journals (Sweden)

    Shaoming Pan

    Full Text Available Declustering techniques are widely used in distributed environments to reduce query response time through parallel I/O by splitting large files into several small blocks and then distributing those blocks among multiple storage nodes. Unfortunately, however, many small geospatial image data files cannot be further split for distributed storage. In this paper, we propose a complete theoretical system for the distributed storage of small geospatial image data files based on mining the access patterns of geospatial image data using their historical access log information. First, an algorithm is developed to construct an access correlation matrix based on the analysis of the log information, which reveals the patterns of access to the geospatial image data. Then, a practical heuristic algorithm is developed to determine a reasonable solution based on the access correlation matrix. Finally, a number of comparative experiments are presented, demonstrating that our algorithm displays a higher total parallel access probability than those of other algorithms by approximately 10-15% and that the performance can be further improved by more than 20% by simultaneously applying a copy storage strategy. These experiments show that the algorithm can be applied in distributed environments to help realize parallel I/O and thereby improve system performance.

  2. Distributed Storage Algorithm for Geospatial Image Data Based on Data Access Patterns.

    Science.gov (United States)

    Pan, Shaoming; Li, Yongkai; Xu, Zhengquan; Chong, Yanwen

    2015-01-01

    Declustering techniques are widely used in distributed environments to reduce query response time through parallel I/O by splitting large files into several small blocks and then distributing those blocks among multiple storage nodes. Unfortunately, however, many small geospatial image data files cannot be further split for distributed storage. In this paper, we propose a complete theoretical system for the distributed storage of small geospatial image data files based on mining the access patterns of geospatial image data using their historical access log information. First, an algorithm is developed to construct an access correlation matrix based on the analysis of the log information, which reveals the patterns of access to the geospatial image data. Then, a practical heuristic algorithm is developed to determine a reasonable solution based on the access correlation matrix. Finally, a number of comparative experiments are presented, demonstrating that our algorithm displays a higher total parallel access probability than those of other algorithms by approximately 10-15% and that the performance can be further improved by more than 20% by simultaneously applying a copy storage strategy. These experiments show that the algorithm can be applied in distributed environments to help realize parallel I/O and thereby improve system performance.

  3. Prediction of gasoline yield in a fluid catalytic cracking (FCC riser using k-epsilon turbulence and 4-lump kinetic models: A computational fluid dynamics (CFD approach

    Directory of Open Access Journals (Sweden)

    Muhammad Ahsan

    2015-07-01

    Full Text Available Fluid catalytic cracking (FCC is an essential process for the conversion of gas oil to gasoline. This study is an effort to model the phenomenon numerically using commercial computational fluid dynamics (CFD software, heavy density catalyst and 4-lump kinetic model. Geometry, boundary conditions and dimensions of industrial riser for catalytic cracking unit are conferred for 2D simulation using commercial CFD code FLUENT 6.3. Continuity, momentum, energy and species transport equations, applicable to two phase solid and gas flow, are used to simulate the physical phenomenon as efficient as possible. This study implements and predicts the use of the granular Eulerian multiphase model with species transport. Time accurate transient problem is solved with the prediction of mass fraction profiles of gas oil, gasoline, light gas and coke. The output curves demonstrate the breaking of heavy hydrocarbon in the presence of catalyst. An approach proposed in this study shows good agreement with the experimental and numerical data available in the literature.

  4. Energy efficient design of cognitive small cells

    NARCIS (Netherlands)

    Wildemeersch, Matthias; Wildemeersch, Matthias; Quek, Tony Q.S.; Rabbachin, Alberto; Slump, Cornelis H.; Huang, Aiping; Kim, Dong-In; Mueller, P.

    2013-01-01

    Heterogeneous networks consisting of a macrocell tier and a small cell tier are considered an attractive solution to cope with the fierce increase of mobile traffic demand. Nevertheless, a massive deployment of small cell access points (SAPs) leads also to a considerable increase in energy

  5. Small hydro in Africa

    CSIR Research Space (South Africa)

    Jonker Klunne, W

    2011-10-01

    Full Text Available hydro, the author has started an online database of small hydropower projects in eastern and southern Africa. The main aim of the database is to catalogue the current situation and to make that accessible to policymakers, project developers, as well...

  6. Toward Generalization of Iterative Small Molecule Synthesis.

    Science.gov (United States)

    Lehmann, Jonathan W; Blair, Daniel J; Burke, Martin D

    2018-02-01

    Small molecules have extensive untapped potential to benefit society, but access to this potential is too often restricted by limitations inherent to the customized approach currently used to synthesize this class of chemical matter. In contrast, the "building block approach", i.e., generalized iterative assembly of interchangeable parts, has now proven to be a highly efficient and flexible way to construct things ranging all the way from skyscrapers to macromolecules to artificial intelligence algorithms. The structural redundancy found in many small molecules suggests that they possess a similar capacity for generalized building block-based construction. It is also encouraging that many customized iterative synthesis methods have been developed that improve access to specific classes of small molecules. There has also been substantial recent progress toward the iterative assembly of many different types of small molecules, including complex natural products, pharmaceuticals, biological probes, and materials, using common building blocks and coupling chemistry. Collectively, these advances suggest that a generalized building block approach for small molecule synthesis may be within reach.

  7. Toward Generalization of Iterative Small Molecule Synthesis

    Science.gov (United States)

    Lehmann, Jonathan W.; Blair, Daniel J.; Burke, Martin D.

    2018-01-01

    Small molecules have extensive untapped potential to benefit society, but access to this potential is too often restricted by limitations inherent to the customized approach currently used to synthesize this class of chemical matter. In contrast, the “building block approach”, i.e., generalized iterative assembly of interchangeable parts, has now proven to be a highly efficient and flexible way to construct things ranging all the way from skyscrapers to macromolecules to artificial intelligence algorithms. The structural redundancy found in many small molecules suggests that they possess a similar capacity for generalized building block-based construction. It is also encouraging that many customized iterative synthesis methods have been developed that improve access to specific classes of small molecules. There has also been substantial recent progress toward the iterative assembly of many different types of small molecules, including complex natural products, pharmaceuticals, biological probes, and materials, using common building blocks and coupling chemistry. Collectively, these advances suggest that a generalized building block approach for small molecule synthesis may be within reach. PMID:29696152

  8. Limited access: gender, occupational composition, and flexible work scheduling.

    Science.gov (United States)

    Glauber, Rebecca

    2011-01-01

    The current study draws on national data to explore differences in access to flexible work scheduling by the gender composition of women's and men's occupations. Results show that those who work in integrated occupations are more likely to have access to flexible scheduling. Women and men do not take jobs with lower pay in return for greater access to flexibility. Instead, jobs with higher pay offer greater flexibility. Integrated occupations tend to offer the greatest access to flexible scheduling because of their structural locations. Part-time work is negatively associated with men's access to flexible scheduling but positively associated with women's access. Women have greater flexibility when they work for large establishments, whereas men have greater flexibility when they work for small establishments.

  9. Ultrasound Thrombolysis in Hemodialysis Access: In Vitro Investigation

    International Nuclear Information System (INIS)

    Wildberger, Joachim Ernst; Schmitz-Rode, Thomas; Haage, Patrick; Pfeffer, Joachim; Ruebben, Alexander; Guenther, Rolf W.

    2001-01-01

    Purpose: To evaluate the effectiveness of ultrasound thrombolysis in occluded hemodialysis access shunts using an in vitro model.Methods: Thrombosed hemodialysis accesses were simulated by clotted bovine blood in a flow model (silicone tubing; inner diameters 4, 6, and 9 mm). After retrograde and antegrade sheath placement (7 Fr), mechanical thrombolysis was performed using an ultrasound probe (Acolysis, Angiosonics, Morrisville, NC, USA). The tip of the device measured 2.2 mm in diameter. During sonication, the catheter was moved slowly back and forth using an over-the-wire system. Thirty complete occlusions [tubing diameters 4 mm (n = 12), 6 mm (n = 12), 9 mm (n = 6)] were treated. Initial thrombus weights were 3.5 (± 0.76) g, 7.7 (± 1.74) g, and 19.4 (± 2.27) g for the three diameters. Maximum sonication time was 15 min for each probe.Results: With this device, we were able to restore a continuous lumen in all 12 occluded 4∼mm silicone tubes. No wall-adherent thrombi remained after sonication for 3.5-9.6 min. In hemodialysis access models with diameters of 6 mm, thrombus fragments persisted in 25% (3/12 accesses). These were located in the medial portion of the access loop and near to the puncture sites. However, flow was re-established after 5.0-13.0 min of treatment in all settings. Mechanical dissolution of thrombus material failed in five of six access models with diameters of 9 mm, even though ultrasound energy was applied for the maximum of 15 min.Conclusion: In a clotted hemodialysis shunt model, successful ultrasound thrombolysis was limited to small access diameters and small amounts of thrombus

  10. Policy principles for expanding financial access: report of the CGD task force on access to financial services

    NARCIS (Netherlands)

    Claessens, S.; Honohan, P.; Rojas-Suarez, L.

    2009-01-01

    Despite the rapid growth in finance worldwide over the past quarter-century — now interrupted by the global financial crisis — many low-income households and small firms remain excluded from access to many financial services, especially in developing countries. While traditionally seen by many

  11. The optimal access system for future far-offshore wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Obdam, T.S.; Rademakers, L.W.M.M.; Savenije, L.B. [ECN Wind Energy, Petten (Netherlands)

    2013-12-15

    Operation and maintenance (O and M) of offshore wind turbines is one of the main cost drivers of offshore wind energy. One of the aspects critical for an efficient and cost-effective O and M strategy is the selection of the access system which is used to transfer technicians and, optionally, small spare parts. Currently, most offshore wind farms are located close to shore, and their size is relatively small. For these farms the typical access system consists of catamaran-like workboats, which are used to transfer both technicians and small spare parts. As wind farms move further offshore this O and M concept might no longer be cost-effective. Currently, different alternative O and M concepts are being considered for the future far-offshore sites. In this paper an extensive and holistic comparison of different O and M concepts including different access system solutions is presented. This analysis has been performed using the OMCECalculator, ECN's software for advanced O and M cost modelling. Different sites have been considered, which are typical for the future offshore wind farms that will be commissioned during the next five years. The results of the performed analyses indicate that when moving further offshore harbour-based O and M strategies are no longer economical, even when helicopters are added to the mix. Looking at farm-based O and M concepts a supply vessel with a compensated access gangway offers great potential. However, the calculations also indicate that its ability to transfer small spare parts, in addition to technicians, is crucial.

  12. Optical Access Networks

    Science.gov (United States)

    Zheng, Jun; Ansari, Nirwan

    2005-01-01

    Call for Papers: Optical Access Networks Guest Editors Jun Zheng, University of Ottawa Nirwan Ansari, New Jersey Institute of Technology Submission Deadline: 1 June 2005 Background With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the economic viability of many potential high-bandwidth applications. In recent years, optical access networks

  13. Access Agent Improving The Performance Of Access Control Lists

    Directory of Open Access Journals (Sweden)

    Thelis R. S.

    2015-08-01

    Full Text Available The main focus of the proposed research is maintaining the security of a network. Extranet is a popular network among most of the organizations where network access is provided to a selected group of outliers. Limiting access to an extranet can be carried out using Access Control Lists ACLs method. However handling the workload of ACLs is an onerous task for the router. The purpose of the proposed research is to improve the performance and to solidify the security of the ACLs used in a small organization. Using a high performance computer as a dedicated device to share and handle the router workload is suggested in order to increase the performance of the router when handling ACLs. Methods of detecting and directing sensitive data is also discussed in this paper. A framework is provided to help increase the efficiency of the ACLs in an organization network using the above mentioned procedures thus helping the organizations ACLs performance to be improved to be more secure and the system to perform faster. Inbuilt methods of Windows platform or Software for open source platforms can be used to make a computer function as a router. Extended ACL features allow the determining of the type of packets flowing through the router. Combining these mechanisms allows the ACLs to be improved and perform in a more efficient manner.

  14. Evaluating Expected Costs and Benefits of Granting Access to New Treatments on the Basis of Progression-Free Survival in Non-Small-Cell Lung Cancer.

    Science.gov (United States)

    Lakdawalla, Darius N; Chou, Jacquelyn W; Linthicum, Mark T; MacEwan, Joanna P; Zhang, Jie; Goldman, Dana P

    2015-05-01

    Surrogate end points may be used as proxy for more robust clinical end points. One prominent example is the use of progression-free survival (PFS) as a surrogate for overall survival (OS) in trials for oncologic treatments. Decisions based on surrogate end points may expedite regulatory approval but may not accurately reflect drug efficacy. Payers and clinicians must balance the potential benefits of earlier treatment access based on surrogate end points against the risks of clinical uncertainty. To present a framework for evaluating the expected net benefit or cost of providing early access to new treatments on the basis of evidence of PFS benefits before OS results are available, using non-small-cell lung cancer (NSCLC) as an example. A probabilistic decision model was used to estimate expected incremental social value of the decision to grant access to a new treatment on the basis of PFS evidence. The model analyzed a hypothetical population of patients with NSCLC who could be treated during the period between PFS and OS evidence publication. Estimates for delay in publication of OS evidence following publication of PFS evidence, expected OS benefit given PFS benefit, incremental cost of new treatment, and other parameters were drawn from the literature on treatment of NSCLC. Incremental social value of early access for each additional patient per month (in 2014 US dollars). For "medium-value" model parameters, early reimbursement of drugs with any PFS benefit yields an incremental social cost of more than $170,000 per newly treated patient per month. In contrast, granting early access on the basis of PFS benefit between 1 and 3.5 months produces more than $73,000 in incremental social value. Across the full range of model parameter values, granting access for drugs with PFS benefit between 3 and 3.5 months is robustly beneficial, generating incremental social value ranging from $38,000 to more than $1 million per newly treated patient per month, whereas access

  15. Qualification of new design of flexible pipe against singing: testing at multiple scales

    NARCIS (Netherlands)

    Golliard, J.; Lunde, K.; Vijlbrief, O.

    2016-01-01

    Flexible pipes for production of oil and gas typically present a corrugated inner surface. This has been identified as the cause of "singing risers": Flow-Induced Pulsations due to the interaction of sound waves with the shear layers at the small cavities present at each of the multiple

  16. Reduced-complexity adaptive multi-channel assignment for shared access points in over-loaded small-cell networks

    KAUST Repository

    Radaydeh, Redha Mahmoud

    2013-06-01

    This paper proposes a reduced-complexity downlink multi-channel assignment scheme when feedback links are capacity-limited. The system model treats the case when multiple access points are allocated to serve scheduled users in over-loaded (i.e. dense) pico/femtocell networks. It assumes that the deployed access points can be shared simultaneously and employ isotropic antenna arrays of arbitrary sizes. Moreover, they transmit their data on a common physical channel and can not coordinate their transmissions. On the other hand, each scheduled user can be served by single transmit channel from each active access point at a time, and it lacks coordination with concurrent active users. The scheme operates according to the occupancy of available transmit channels, wherein extensively occupied access points are avoided adaptively, while reducing the load of processing. The operation is linked to a target performance via controlling the observed aggregate interference from the projected set of serving points. Through the analysis, results for the scheduled user outage performance, and the average number of active access points are presented. Numerical and simulations studies clarify the gains of the proposed scheme for different operating conditions. © 2013 IEEE.

  17. Reduced-complexity adaptive multi-channel assignment for shared access points in over-loaded small-cell networks

    KAUST Repository

    Radaydeh, Redha Mahmoud; Qaraqe, Khalid A.; Alouini, Mohamed-Slim

    2013-01-01

    This paper proposes a reduced-complexity downlink multi-channel assignment scheme when feedback links are capacity-limited. The system model treats the case when multiple access points are allocated to serve scheduled users in over-loaded (i.e. dense) pico/femtocell networks. It assumes that the deployed access points can be shared simultaneously and employ isotropic antenna arrays of arbitrary sizes. Moreover, they transmit their data on a common physical channel and can not coordinate their transmissions. On the other hand, each scheduled user can be served by single transmit channel from each active access point at a time, and it lacks coordination with concurrent active users. The scheme operates according to the occupancy of available transmit channels, wherein extensively occupied access points are avoided adaptively, while reducing the load of processing. The operation is linked to a target performance via controlling the observed aggregate interference from the projected set of serving points. Through the analysis, results for the scheduled user outage performance, and the average number of active access points are presented. Numerical and simulations studies clarify the gains of the proposed scheme for different operating conditions. © 2013 IEEE.

  18. PILOT SCALE TESTING OF MONOSODIUM TITANATE MIXING FOR THE SRS SMALL COLUMN ION EXCHANGE PROCESS - 11224

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M.; Restivo, M.; Williams, M.; Herman, D.; Steeper, T.

    2011-01-25

    The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and select actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for suspending monosodium titanate (MST), crystalline silicotitanate (CST), and simulated sludge. The purpose of this pilot scale testing is to determine the requirements for the pumps to suspend the MST particles so that they can contact the strontium and actinides in the liquid and be removed from the tank. The pilot-scale tank is a 1/10.85 linear scaled model of SRS Tank 41H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 41H. The pump locations correspond to the proposed locations in Tank 41H by the SCIX program (Risers B5 and B2 for two pump configurations and Risers B5, B3, and B1 for three pump configurations). The conclusions from this work follow: (i) Neither two standard slurry pumps nor two quad volute slurry pumps will provide sufficient power to initially suspend MST in an SRS waste tank. (ii) Two Submersible Mixer Pumps (SMPs) will provide sufficient power to initially suspend MST in an SRS waste tank. However, the testing shows the required pump discharge velocity is close to the maximum discharge velocity of the pump (within 12%). (iii) Three SMPs will provide sufficient power to initially suspend MST in an SRS waste tank. The testing shows the required pump discharge velocity is 66% of the maximum discharge velocity of the pump. (iv) Three SMPs are needed to resuspend MST that has settled in a waste tank at nominal 45 C for four weeks. The testing shows the required pump discharge velocity is 77% of the maximum discharge velocity of the pump. Two SMPs are not sufficient to resuspend MST that settled under these

  19. Mastery of innovation risk in deep sea developments (part 1) - Drilling and well - round table no.4; Maitrise du risque de l'innovation dans le developpement en grand fond (1. partie) - le forage et le puits - table ronde no.4

    Energy Technology Data Exchange (ETDEWEB)

    Charlez, Ph.A.; Lassus Dessus, J.; Gazaniol, D. [TotalFinaElf, La Defense, 92 - Courbevoie (France); Guesnon, J. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France); Hudson, W. [DORIS Engineering, 75 - Paris (France); Chauvin, H. [Geoservices S.A., 93 - Le Blanc Mesnil (France)

    2003-02-01

    This round table comprises 5 articles dealing with: 1) - the specific problems and drilling risks in very deep waters: risers (diameter, length, volume and weight), sea bottom conditions (high pressure and low temperature), and management of drilling mud weight (pore and fracturing pressures window, mud hydrates formation); 2) - the implementation of risers in very deep waters: risers mechanical properties (tension, weight), stresses on connected and non-connected risers, possible improvements (reduction of mud and riser weights), steel/composite technology for safety lines, lack of knowledge in the implementation of risers (vibrations, fatigue sources, simulation codes, optimization), instrumentation system for risers; 3) - drilling with surface BOP (blow out preventers): advantages and domains of use, risk management; 4) - safety using gas measurement in very deep drilling: detection of gas events (H{sub 2}S, alkanes, CO{sub 2}, benzene, toluene, xylene) during well drilling, improvement of detectors, implementation, reliability; 5) - Girassol field drillings and completions: contractual strategy, wells design, productivity, drilling and completion, underwater systems. (J.S.)

  20. Numériser et mettre en ligne

    CERN Document Server

    Claerr, Thierry

    2010-01-01

    Rendre les collections accessibles en ligne est devenu pour les institutions culturelles, d'enseignement et de recherche, un des défis majeurs du début du XXIe siècle. Les projets sont dès à présent nombreux, et concernent tous les types d'établissements et tous les supports. Mener à bien une opération de numérisation et de mise en ligne requiert un ensemble de repères et de connaissances pour l'organisation et la mise en oeuvre d'un projet de numérisation durable. Donner les clés du domaine en se fondant sur des savoirs pratiques et concrets est l'ambition de cet ouvrage, qui fournit un mode opératoire précis pour chacune des grandes étapes à prendre en compte - de la capture à la conservation numérique, en passant par l'interopérabilité, le référencement, et en intégrant l'environnement juridique et réglementaire. Coordonné par Thierry Claerr et Isabelle Westeel, spécialistes du sujet et responsables de formations sur la numérisation et la création de bibliothèques numériques,...

  1. Encouraging the Domestic Small Turbine Market

    International Nuclear Information System (INIS)

    Forsyth, T.

    2001-01-01

    The state incentives for home-based renewables in the domestic market continue to grow and change creating opportunities for the small wind turbine market. Tracking the opportunities to get small wind turbines included in incentive policies and developing a proactive industry approach is important because market changes can occur anytime. There are near-term opportunities to work with states in developing their strategies for disbursing system benefit charges, adding tags to existing policies for other small renewables to include small wind, and developing state-wide net metering programs. Other opportunities to improve the domestic market exist but will be quite challenging to implement. Other opportunities include federal tax credits, state wind access laws, equipment verification for specific states, and leasing programs for small wind turbines

  2. Small millet farmers increase yields through participatory varietal ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Small millets, despite being rich in micronutrients and dietary fibre and known for their low glycemic index and tolerance of water stress, are in decline in South Asia. Existing varieties suffer from low yield and farmers lack access to improved varieties. The Revalorising Small Millets in Rainfed Regions of South Asia ...

  3. Open-access publishing for pharmacy-focused journals.

    Science.gov (United States)

    Clauson, Kevin A; Veronin, Michael A; Khanfar, Nile M; Lou, Jennie Q

    2008-08-15

    Pharmacy-focused journals that are available in open-access (OA), freely accessible, hybrid, or traditional formats were identified. Relevant journals were accessed from PubMed, International Pharmaceutical Abstracts, EMBASE, and the Pharmacology and Pharmacy category of Thomson Scientific Journal Citation Reports. Criteria were established to select journals that satisfied the definition of pharmacy focused. Journals were assessed based on accessibility, copyright transfer requirements, and restrictions. If tracked, the journal's impact factor (IF) was identified according to classification, and medians were calculated for each journal category. A total of 317 pharmacy-focused journals were identified. The majority of pharmacy-focused journals identified were traditional/non-OA (n = 240). A smaller number of journals were freely accessible/ non-OA (n = 37), freely accessible/non-OA with content restrictions (n = 20), or freely available/non-OA with date restrictions (n = 18). The fewest number of journals were completely OA (n = 2). The median IF for the 185 journals whose IF was tracked was 2.029. The median IF for freely accessible and hybrid journals (n = 42) was 2.550, whereas the median IF for traditional journals (n = 143) was 1.900. A very small number of pharmacy-focused journals adhere to the OA paradigm of access. However, journals that adopt some elements of the OA model, chiefly free accessibility, may be more likely to be cited than traditional journals. Pharmacy practitioners, educators, and researchers could benefit from the advantages that OA offers but should understand its financial disadvantages.

  4. Combining sync&share functionality with filesystem-like access

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    In our presentation we will analyse approaches to combine the sync & share functionality with file system-like access to data. While relatively small data volumes (GBs) can be distributed by sync&share application across user devices such as PCs, laptops and mobiles, interacting with really large data volumes (TBs, PBs) may require additional remote data access mechanism such as filesystem-like interface. We will discuss several ways for offering filesystem-like access in addition to sync & share functionality. Todays sync & share solutions may employ various data organisation in the back-end including local and distributed file systems and object stores. Therefore various approaches to providing the client with filesystem-like access are necessary in these systems. We will present possible options to integrate the filesystem-like access with sync&share functionality in the popular sync&share system. We will also show a NDS2 project solution where data backups and archives are kept sec...

  5. American Thyroid Association Statement on Remote-Access Thyroid Surgery.

    Science.gov (United States)

    Berber, Eren; Bernet, Victor; Fahey, Thomas J; Kebebew, Electron; Shaha, Ashok; Stack, Brendan C; Stang, Michael; Steward, David L; Terris, David J

    2016-03-01

    Remote-access techniques have been described over the recent years as a method of removing the thyroid gland without an incision in the neck. However, there is confusion related to the number of techniques available and the ideal patient selection criteria for a given technique. The aims of this review were to develop a simple classification of these approaches, describe the optimal patient selection criteria, evaluate the outcomes objectively, and define the barriers to adoption. A review of the literature was performed to identify the described techniques. A simple classification was developed. Technical details, outcomes, and the learning curve were described. Expert opinion consensus was formulated regarding recommendations for patient selection and performance of remote-access thyroid surgery. Remote-access thyroid procedures can be categorized into endoscopic or robotic breast, bilateral axillo-breast, axillary, and facelift approaches. The experience in the United States involves the latter two techniques. The limited data in the literature suggest long operative times, a steep learning curve, and higher costs with remote-access thyroid surgery compared with conventional thyroidectomy. Nevertheless, a consensus was reached that, in appropriate hands, it can be a viable option for patients with unilateral small nodules who wish to avoid a neck incision. Remote-access thyroidectomy has a role in a small group of patients who fit strict selection criteria. These approaches require an additional level of expertise, and therefore should be done by surgeons performing a high volume of thyroid and robotic surgery.

  6. The Internet, Bank Structure and Small Business Lending

    OpenAIRE

    Steven G. Craig; Polly T. Hardee

    2002-01-01

    The advent of the Internet has opened many opportunities for bankers to access new customers, increase convenience and expand product ranges in many markets, including that of small businesses. Yet anecdotal evidence reveals that smaller banks are reluctant to employ Internet technology in the small business market for fear of damaging the customer relationship developed through personal contact. These smaller, more simply structured banks tend to specialize in small business lending, possess...

  7. Cognitive small cell networks: energy efficiency and trade-offs

    NARCIS (Netherlands)

    Wildemeersch, M.; Wildemeersch, Matthias; Quek, T.Q.S.; Slump, Cornelis H.; Rabbachin, A.

    2013-01-01

    Heterogeneous networks using a mix of macrocells and small cells are foreseen as one of the solutions to meet the ever increasing mobile traffic demand. Nevertheless, a massive deployment of small cell access points (SAPs) leads also to a considerable increase in energy consumption. Spurred by

  8. Complication with Intraosseous Access: Scandinavian Users’ Experience

    Science.gov (United States)

    Hallas, Peter; Brabrand, Mikkel; Folkestad, Lars

    2013-01-01

    Introduction: Intraosseous access (IO) is indicated if vascular access cannot be quickly established during resuscitation. Complication rates are estimated to be low, based on small patient series, model or cadaver studies, and case reports. However, user experience with IO use in real-life emergency situations might differ from the results in the controlled environment of model studies and small patient series. We performed a survey of IO use in real-life emergency situations to assess users’ experiences of complications. Methods: An online questionnaire was sent to Scandinavian emergency physicians, anesthesiologists and pediatricians. Results: 1,802 clinical cases of IO use was reported by n=386 responders. Commonly reported complications with establishing IO access were patient discomfort/pain (7.1%), difficulties with penetration of periosteum with IO needle (10.3%), difficulties with aspiration of bone marrow (12.3%), and bended/broken needle (4.0%). When using an established IO access the reported complications were difficulties with injection fluid and drugs after IO insertion (7.4%), slow infusion (despite use of pressure bag) (8.8%), displacement after insertion (8.5%), and extravasation (3.7%). Compartment syndrome and osteomyelitis occurred in 0.6% and 0.4% of cases respectively. Conclusion: In users’ recollection of real-life IO use, perceived complications were more frequent than usually reported from model studies. The perceived difficulties with using IO could affect the willingness of medical staff to use IO. Therefore, user experience should be addressed both in education of how to use, and research and development of IOs. PMID:24106537

  9. Big Data solutions on a small scale: Evaluating accessible high-performance computing for social research

    OpenAIRE

    Murthy, Dhiraj; Bowman, S. A.

    2014-01-01

    Though full of promise, Big Data research success is often contingent on access to the newest, most advanced, and often expensive hardware systems and the expertise needed to build and implement such systems. As a result, the accessibility of the growing number of Big Data-capable technology solutions has often been the preserve of business analytics. Pay as you store/process services like Amazon Web Services have opened up possibilities for smaller scale Big Data projects. There is high dema...

  10. Small reactors in the Canadian context: opportunities and challenges

    Energy Technology Data Exchange (ETDEWEB)

    Walker, R.S. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2013-07-01

    This presentation discusses the opportunities and challenges for small reactors in Canada. It concludes by suggesting that the success of small reactors in Canada will depend on a number of factors including private sector investment, access to international markets, stable, equitable and adaptable regulatory regime, public trust and technology.

  11. Polynomial reconstruction of radial catalyst concentration distribution in an experimental type FCC riser for a low number of transversal projections in gamma ray tomography

    International Nuclear Information System (INIS)

    Melo, Silvio B.; Simoes, Francisco P.M.; Oliveira, Eric F. de; Santos, Maria das Gracas dos; Dantas, Carlos C.

    2007-01-01

    In the FCC - Fluid Catalytic Cracking process the Riser is an opaque cylinder, so that, in order to investigate the catalyst concentration inside, a gamma- ray based tomography is employed. Each section is submitted to a parallel beam and by means of the Beer-Lambert transmission is calculated. This tomography session is repeated from different angles, in manual tomographic experiments where the source/detector pair is rotated, producing in each direction what we called a transversal projection. In order to reconstruct the concentration of the present catalyst in a given moment some methods use successfully the inverse Radon transform through the filtered back-projection algorithm. The results are fully satisfactory for a large number of projections, widely seen as better than those produced by the algebraic methods. For a low number of projections, however, the algebraic methods become more competitive. In practice, simple experimental set-ups work with less than 10 projections, due to the time taken by the whole process. In this work, we present an investigation of polynomial reconstructions by using Bezier surfaces of arbitrary degree, adjusted to the experimental data through a least squares method. A computational algorithm was developed to implement the mathematical reconstruction for the 3D graphics presentation. (author)

  12. Technology Adoption: Influence of Availability and Accessibility

    Science.gov (United States)

    McConnell, William Stewart

    2009-01-01

    Farmers are small business leaders using available technology to remain competitive. The availability of technology is dependent on the suppliers' use of the marketing mix 4Ps theory--product, price, placement, and promotion. The purpose of this study was to determine how the relation between availability and accessibility influences the adoption…

  13. 76 FR 13769 - Rural Broadband Access Loans and Loan Guarantees

    Science.gov (United States)

    2011-03-14

    ... pharmacy work, and savings to health facilities from outsourcing specialized medical procedures. One study... international markets and enables new, small, and home-based businesses to thrive. Broadband access affords...

  14. Negócios nanicos, garantias e acesso a crédito Small business, colateral and access to credit

    Directory of Open Access Journals (Sweden)

    Marcelo Côrtes Neri

    2005-12-01

    Full Text Available O trabalho realiza uma análise empírica dos determinates do uso de crédito a partir de amostra de 50 mil empresas formais e informais por conta própria ou empregadoras até cinco empregados a partir da Pesquisa Economia Informal Urbana (ECINF do IBGE. O objetivo é contribuir para o desenvolvimento do crédito produtivo popular no Brasil. O mercado de microcrédito se revela incipiente: apenas 13,7% dos nanonegócios apresentavam dívida pendente, a concentração dos estoques de dívida entre os 10% mais altos valores neste segmento é de 98,5% contra 60,8% do faturamento e 59,4% do lucro. Complementarmente, 7% dos nanonegócios obtiveram acesso a crédito nos três meses anteriores à pesquisa. Apresentamos o padrão de correlações do uso do crédito produtivo popular com outras variáveis, baseadas em um modelo logístico rodado a partir dos microdados da ECINF. Constatamos que alguns elementos do capital social como participação em cooperativas, indicadores de formalidade e posse de equipamentos apresentam correlação significativa com o acesso a crédito. Em geral, os resultados são consistentes com a importância atribuída na literatura a garantias reais e alternativas na obtenção de fontes de financiamento.The paper aims to contributing to the development of microcredit policies in Brazil. The current paper benefits from the survey about the Informal Urban Economy - ECINF, performed by the IBGE, where almost 50,000 self-employed and those employing up to five employees were interviewed. The microcredit market reveals to be incipient in the country's urban areas; only 7% of small businesses attained access to credit in the three months prior to the survey. We describe the pattern of correlation of access to productive credit use with other variables, in particular those connected with the ownership of real guarantees or social capital elements. The possession of equipments and the membership to cooperatives are positively

  15. Accessibility of islands: towards a new geography based on transportation modes and choices

    Directory of Open Access Journals (Sweden)

    Sofia Karampela

    2014-11-01

    Full Text Available Accessibility is a multifaceted concept that expresses the case of access between two points in space. For islands, accessibility is a key quality, since isolation and small size considered as inherent characteristics of “islandness”. In this paper, we discuss differences between geographical distance and accessibility potential in the Greek Aegean, combining different transportation modal choice (ferries and airplanes with the use of an accessibility index that incorporates modes and frequency of connection and data of actual usage. The findings indicate that geographical distance is not determining accessibility and new geographies emerge based more on the availability of transport modal choices.

  16. Information Access for Disabled Students

    OpenAIRE

    Cypaite, Asta; Šerkšnien, Justina; Rudžioniene, Jurgita

    2008-01-01

    Disabled students who makes relatively small part of the academic society are in risk to disappear among all other students, due to their communication and mobility difficulties have less possibilities to satisfy their needs, ensuring their rights to qualitative studies, equal opportunities in the labor market and social integration. A topic about information accessibility for disabled students is extremely important because of their information exclusion in their study process at the un...

  17. Usability testing of the human-machine interface for the Light Duty Utility Arm System

    International Nuclear Information System (INIS)

    Kiebel, G.R.; Ellis, J.E.; Masliah, M.R.

    1994-01-01

    This report describes the usability testing that has been done for the control and data acquisition system for the Light Duty Utility Arm (LDUA) System. A program of usability testing has been established as a part of a process for making the LDUA as easy to use as possible. The LDUA System is being designed to deploy a family of tools, called End Effectors, into underground storage tanks by means of a robotic arm on the end of a telescoping mast, and to collect and manage the data that they generate. The LDUA System uses a vertical positioning mast, to lower the arm into a tank through an existing 30.5 cm access riser. A Mobile Deployment Subsystem is used to position the mast and arm over a tank riser for deployment, and to transport them from tank to tank. The LDUA System has many ancillary subsystems including the Operations Control Trailer, the Tank Riser Interface and Confinement Subsystem, the Decontamination Subsystem, and the End Effector Exchange Subsystem. This work resulted in the identification of several important improvements to the LDUA control and data acquisition system before the design was frozen. The most important of these were color coding of joints in motion, simultaneous operator control of multiple joints, and changes to the field-of-views of the camera lenses for the robot and other camera systems

  18. Coexistence of Cognitive Small Cell and WiFi System: A Traffic Balancing Dual-Access Resource Allocation Scheme

    Directory of Open Access Journals (Sweden)

    Xiaoge Huang

    2018-01-01

    Full Text Available We consider a holistic approach for dual-access cognitive small cell (DACS networks, which uses the LTE air interface in both licensed and unlicensed bands. In the licensed band, we consider a sensing-based power allocation scheme to maximize the sum data rate of DACSs by jointly optimizing the cell selection, the sensing operation, and the power allocation under the interference constraint to macrocell users. Due to intercell interference and the integer nature of the cell selection, the resulting optimization problems lead to a nonconvex integer programming. We reformulate the problem to a nonconvex power allocation game and find the relaxed equilibria, quasi-Nash equilibrium. Furthermore, in order to guarantee the fairness of the whole system, we propose a dynamic satisfaction-based dual-band traffic balancing (SDTB algorithm over licensed and unlicensed bands for DACSs which aims at maximizing the overall satisfaction of the system. We obtain the optimal transmission time in the unlicensed band to ensure the proportional fair coexistence with WiFi while guaranteeing the traffic balancing of DACSs. Simulation results demonstrate that the SDTB algorithm could achieve a considerable performance improvement relative to the schemes in literature, while providing a tradeoff between maximizing the total data rate and achieving better fairness among networks.

  19. Complication with Intraosseous Access: Scandinavian Users' Experience

    Directory of Open Access Journals (Sweden)

    Peter Hallas

    2013-09-01

    Full Text Available Introduction: Intraosseous access (IO is indicated if vascular access cannot be quickly established during resuscitation. Complication rates are estimated to be low, based on small patient series, model or cadaver studies, and case reports. However, user experience with IO use in real-life emergency situations might differ from the results in the controlled environment of model studies and small patient series. We performed a survey of IO use in real-life emergency situations to assess users’ experiences of complications.Methods: An online questionnaire was sent to Scandinavian emergency physicians, anesthesiologists and pediatricians.Results: 1,802 clinical cases of IO use was reported by n=386 responders. Commonly reported complications with establishing IO access were patient discomfort/pain (7.1%, difficulties with penetration of periosteum with IO needle (10.3%, difficulties with aspiration of bone marrow (12.3%, and bended/broken needle (4.0%. When using an established IO access the reported complications were difficulties with injection fluid and drugs after IO insertion (7.4%, slow infusion (despite use of pressure bag (8.8%, displacement after insertion (8.5%, and extravasation (3.7%. Compartment syndrome and osteomyelitis occurred in 0.6% and 0.4% of cases respectively.Conclusion: In users’ recollection of real-life IO use, perceived complications were more frequent than usually reported from model studies. The perceived difficulties with using IO could affect the willingness of medical staff to use IO. Therefore, user experience should be addressed both in education of how to use, and research and development of IOs. [West J Emerg Med. 2013;14(5:440–443.

  20. Thresholds to access the market for small-scale energy consumers

    International Nuclear Information System (INIS)

    Baarsma, B.; Bremer, S.; De Nooij, M.; Poort, J.

    2007-10-01

    Entry of and options for expansion are import aspects for a well-functioning free market. The Netherlands Competition Authority (NMa)/The Office of Energy Regulation (DTe/Energiekamer) received signals that there are barriers for entering or further growth on the small consumer market. The regulator has asked SEO Economic Research to examine which entry barriers are significant and require further monitoring. For this purpose, more than 20 interviews were held with market parties and stakeholders. [mk] [nl

  1. 6/4 GHz band small capacity omni-use terminal satellite system

    Science.gov (United States)

    Masamura, T.; Inoue, T.

    1983-03-01

    This paper presents system outline and multiple access techniques for a domestic satellite communication system accommodating numerous small earth stations. Two kinds of earth stations are employed in this system, a small earth terminal (SET) and a master earth station (MES). There are 48 both way satellite channels using a 6/4 GHz band transponder whose e.i.r.p is about 62 dBm. The TDM (Time Division Multiplex) method is employed in the MES to SET link, and the SSMA (Spread Spectrum Multiple Access) method is used in the SET to MES link.

  2. 13 CFR 120.1010 - SBA access to SBA Lender, Intermediary, and NTAP files.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false SBA access to SBA Lender, Intermediary, and NTAP files. 120.1010 Section 120.1010 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Risk-Based Lender Oversight Supervision § 120.1010 SBA access to SBA Lender...

  3. State-of-the-Art for Small Satellite Propulsion Systems

    Science.gov (United States)

    Parker, Khary I.

    2016-01-01

    SmallSats are a low cost access to space with an increasing need for propulsion systems. NASA, and other organizations, will be using SmallSats that require propulsion systems to: a) Conduct high quality near and far reaching on-orbit research and b) Perform technology demonstrations. Increasing call for high reliability and high performing for SmallSat components. Many SmallSat propulsion technologies are currently under development: a) Systems at various levels of maturity and b) Wide variety of systems for many mission applications.

  4. Mobility and accessibility of hispanics in small towns and rural areas.

    Science.gov (United States)

    2014-07-01

    The Hispanic population has increased 43% (from 35.3 million to 50.5 million) in the 2000s in the U.S. Small towns and : rural areas in the U.S. are among the areas that have experienced rapid growth in : the : Hispanic immigrant population in the : ...

  5. 77 FR 25042 - Small Business Investment Companies-Early Stage SBICs

    Science.gov (United States)

    2012-04-27

    ... entrepreneurs' access to capital and encourage innovation as part of President Obama's Start-Up America... startups and small firms, accelerate research, and address barriers to success for entrepreneurs and small... and limit the initiative's impact on leverage fees, although fee increases will still be necessary. On...

  6. Contributions of Small-Scale Community-Owned Infrastructure (SCI ...

    African Journals Online (AJOL)

    Contributions of Small-Scale Community-Owned Infrastructure (SCI) and Asset ... Descriptive analysis was employed to explain access to productive rural ... for asset maintenance and replacement; support targeted value chains given the ...

  7. National Dam Safety Program. Grindstone-Lost-Muddy Creek Dam F-20 (MO 11220), Grand - Chariton Basin, Daviess County, Missouri. Phase I Inspection Report.

    Science.gov (United States)

    1980-06-01

    for a small dam having a high hazard potential. Considering the small volume of water im- pounded and the downstream channel from the dam, one-half of...flood at damsite - Mr. Wesley Lee reported that the highest water he had seen was approximately 4 inches over the riser. (3) The principal spillway...operation. It was reported by Mr. Wesley Lee that the emergency spillway has never operated. 2.4 EVALUATION a. Availabilit X . The data in Appendix C

  8. IODP Expedition 338: Riser and Riserless Drilling Along the NanTroSEIZE Transect

    Science.gov (United States)

    Strasser, M.; Moore, G. F.; Dugan, B.; Kanagawa, K.; Toczko, S.

    2013-12-01

    Integrated Ocean Drilling Program (IODP) Expedition 338 provided new constraints on the Kumano Basin sediments, the accretionary prism inner wedge, the seaward extension of the megasplay fault, the architecture and mechanics of landslides, and the alteration of oceanic basement of the incoming Philippine Sea plate. This was accomplished through riser and riserless drilling, logging while drilling (LWD), and cuttings and core analysis. Cuttings and LWD analyses at Hole C0002F reveal two lithologic units in the prism inner wedge which are separated by a prominent fault zone at ~1640 mbsf. Mud-gases from the inner prism show high concentrations at the top of the wedge that decrease, but become more thermogenic, with depth. These data are from the previously unaccessed deeper part of the Nankai accretionary prism. Riserless coring at Site C0002 provided data across the gas hydrate zone of the Kumano Basin, across the Kumano Basin-accretionary prism unconformity, and in the uppermost accretionary prism. Within the Kumano basin section, gas and porewater geochemistry documents microbial methane gas in hydrates that are disseminated in sandy layers. Multiple penetrations of the Kumano Basin-accretionary prism boundary and 3D seismic data show that the boundary is erosive and complex. LWD (Site C0018) and coring and LWD (Site C0021) augment existing data to better understand submarine landslide dynamics and mass-transport deposit (MTD) emplacement processes. Previous coring at Site C0018 identified six MTDs, but only two MTD intervals were detected in resistivity images that show high angle, randomly oriented bedding. Site C0021, located more proximal to the MTD source, provides constraint on MTD variability. Correlation across the sites reveals a thick MTD with an erosional base characterized by a shear zone in muddy sediments vs. a translational basal surface within coarse volcaniclastic sand in the proximal and distal/lateral areas, respectively. LWD data and cores from

  9. Memory states in small arrays of Josephson junctions

    Energy Technology Data Exchange (ETDEWEB)

    Braiman, Yehuda [ORNLOak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computer Science and Mathematics Division, Computing and Computational Science Directorate; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Mechanical, Aerospace, and Biomedical Engineering; Neschke, Brendan [ORNLOak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computer Science and Mathematics Division, Computing and Computational Science Directorate; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Mechanical, Aerospace, and Biomedical Engineering; Nair, Niketh S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computer Science and Mathematics Division, Computing and Computational Science Directorate; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Mechanical, Aerospace, and Biomedical Engineering; Imam, Neena [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computing and Computational Science Directorat; Glowinski, R. [Univ. of Houston, TX (United States). Dept. of Mathematics

    2017-11-30

    Here, we study memory states of a circuit consisting of a small inductively coupled Josephson junction array and introduce basic (write, read, and reset) memory operations logics of the circuit. The presented memory operation paradigm is fundamentally different from conventional single quantum flux operation logics. We calculate stability diagrams of the zero-voltage states and outline memory states of the circuit. We also calculate access times and access energies for basic memory operations.

  10. Policy Interventions Favouring Small Business: Rationales, Results and Recommendations

    Directory of Open Access Journals (Sweden)

    John Lester

    2017-05-01

    Full Text Available Small business has a well-deserved reputation as the driver of job growth and as a key contributor to innovation. In the 12 years ending in 2013, small and medium-sized enterprises (SMEs accounted for about 90% of private sector job growth in Canada. What is less well-recognized, however, is that a small fraction of SMEs account for most of the job growth and innovation. As a result, governments have offered broad-based support for small businesses, rather than focusing on high-impact entrepreneurs. This approach is wasteful: firms that do not grow or innovate receive most of the benefits. Further, this approach can harm economic performance by promoting the expansion of smaller, lessefficient firms at the expense of larger ones. The federal government elected in 2015 is focussing new initiatives on innovative and growth-oriented businesses. Legislated reductions in the small business tax rate were reversed and targeted support for innovative SMEs was increased. While the change in direction is welcome, almost 85% of the $7 billion yearly funding for small business continues to provide broad-based support. The largest program is the special low rate of tax for small businesses, implemented to improve access to financing for capacity-expanding investment. This measure is harming economic performance because the cost of shifting capital and labour from large to smaller, less-efficient businesses outweighs the benefit from improving access to capital. Large subsidies for small business financing are also provided by the Business Development Bank of Canada (BDC. With access to cheap government funding, the BDC is profitable, but evaluated using a more realistic cost of financing, the bank operates at a substantial loss. This loss exceeds the benefit from improving access to capital, particularly for the bank’s direct-lending program. While there is a solid argument for supporting R&D, subsidies provided to small firms are so generous that they are

  11. Patient experience of access to primary care: identification of predictors in a national patient survey.

    Science.gov (United States)

    Kontopantelis, Evangelos; Roland, Martin; Reeves, David

    2010-08-28

    The 2007/8 GP Access Survey in England measured experience with five dimensions of access: getting through on the phone to a practice, getting an early appointment, getting an advance appointment, making an appointment with a particular doctor, and surgery opening hours. Our aim was to identify predictors of patient satisfaction and experience with access to English primary care. 8,307 English general practices were included in the survey (of 8,403 identified). 4,922,080 patients were randomly selected and contacted by post and 1,999,523 usable questionnaires were returned, a response rate of 40.6%. We used multi-level logistic regressions to identify patient, practice and regional predictors of patient satisfaction and experience. After controlling for all other factors, younger people, and people of Asian ethnicity, working full time, or with long commuting times to work, reported the lowest levels of satisfaction and experience of access. For people in work, the ability to take time off work to visit the GP effectively eliminated the disadvantage in access. The ethnic mix of the local area had an impact on a patient's reported satisfaction and experience over and above the patient's own ethnic identity. However, area deprivation had only low associations with patient ratings. Responses from patients in small practices were more positive for all aspects of access with the exception of satisfaction with practice opening hours. Positive reports of access to care were associated with higher scores on the Quality and Outcomes Framework and with slightly lower rates of emergency admission. Respondents in London were the least satisfied and had the worst experiences on almost all dimensions of access. This study identifies a number of patient groups with lower satisfaction, and poorer experience, of gaining access to primary care. The finding that access is better in small practices is important given the increasing tendency for small practices to combine into larger

  12. Patient experience of access to primary care: identification of predictors in a national patient survey

    Directory of Open Access Journals (Sweden)

    Kontopantelis Evangelos

    2010-08-01

    Full Text Available Abstract Background The 2007/8 GP Access Survey in England measured experience with five dimensions of access: getting through on the phone to a practice, getting an early appointment, getting an advance appointment, making an appointment with a particular doctor, and surgery opening hours. Our aim was to identify predictors of patient satisfaction and experience with access to English primary care. Methods 8,307 English general practices were included in the survey (of 8,403 identified. 4,922,080 patients were randomly selected and contacted by post and 1,999,523 usable questionnaires were returned, a response rate of 40.6%. We used multi-level logistic regressions to identify patient, practice and regional predictors of patient satisfaction and experience. Results After controlling for all other factors, younger people, and people of Asian ethnicity, working full time, or with long commuting times to work, reported the lowest levels of satisfaction and experience of access. For people in work, the ability to take time off work to visit the GP effectively eliminated the disadvantage in access. The ethnic mix of the local area had an impact on a patient's reported satisfaction and experience over and above the patient's own ethnic identity. However, area deprivation had only low associations with patient ratings. Responses from patients in small practices were more positive for all aspects of access with the exception of satisfaction with practice opening hours. Positive reports of access to care were associated with higher scores on the Quality and Outcomes Framework and with slightly lower rates of emergency admission. Respondents in London were the least satisfied and had the worst experiences on almost all dimensions of access. Conclusions This study identifies a number of patient groups with lower satisfaction, and poorer experience, of gaining access to primary care. The finding that access is better in small practices is important given

  13. Factors impacting hunter access to private lands in southeast Minnesota

    Science.gov (United States)

    Walberg, Eric; Cornicelli, Louis; Fulton, David C.

    2018-01-01

    White-tailed deer (Odocoileus virginianus) have important socioeconomic and ecological impacts in the United States. Hunting is considered to be important for the effective management of deer and relies on access to privately owned lands. In 2013, we surveyed nonindustrial private landowners in southeast Minnesota and created two logit models to examine factors that impact landowners’ decision to (a) allow public hunting access and (b) post private property. Parcel characteristics were found to impact landowner decisions to allow hunting access, particularly the size of the property and whether it was posted. Hunting access to small properties was more likely to be restricted to family, friends, and neighbors (83%) compared to medium (74%) or large properties (60%). Hunter concerns (e.g., liability) and knowledge about deer management was significant in both models, suggesting there are opportunities to educate landowners about the importance of allowing public hunting access and available liability protections.

  14. Meat Quality Characteristics of Small East African Goats and Norwegian Crosses Finished under Small Scale Farming Conditions.

    Science.gov (United States)

    Hozza, W A; Mtenga, L A; Kifaro, G C; Shija, D S N; Mushi, D E; Safari, J G; Shirima, E J M

    2014-12-01

    The aim of the experiment was to study the effect of feeding system on meat quality characteristics of Small East African (SEA) goats and their crosses with Norwegian (SEA×N) goats finished under small scale farming conditions. Twenty four castrated goats at the age of 18 months with live body weight of 16.7±0.54 kg from each breed (SEA and SEA×N) were distributed in a completely randomized design in a 2×3 factorial arrangement (two breed, and three dietary treatments). The dietary treatments were; no access to concentrate (T0), 66% access to ad libitum concentrate allowance (T66) and 100% access to ad libitum concentrate allowance with 20% refusal (T100) and the experimental period was for 84 days. In addition, all goats were allowed to graze for 2 hours daily and later fed grass hay on ad libitum basis. Daily feed intakes were recorded for all 84-days of experiment after which the animals were slaughtered. Feed intake of T100 animals was 536 g/d, which was 183 g/d higher than that of T66 group. Supplemented goats had significantly (p0.05) for dressing percentage and carcass conformation among supplemented goats except fatness score, total fat depots and carcass fat which increased (pgoats fed concentrate declined rapidly and reached below 6 at 6 h post-mortem but temperature remained at 28°C. Cooking loss and meat tenderness improved (pgoats and their crosses with Norwegian breeds finished under small scale farming conditions in rural areas. Therefore, concentrate supplementation of goats of both breeds improves meat quality attributes.

  15. Interlibrary loan in primary access libraries: challenging the traditional view.

    Science.gov (United States)

    Dudden, R F; Coldren, S; Condon, J E; Katsh, S; Reiter, C M; Roth, P L

    2000-10-01

    Primary access libraries serve as the foundation of the National Network of Libraries of Medicine (NN/LM) interlibrary loan (ILL) hierarchy, yet few published reports directly address the important role these libraries play in the ILL system. This may reflect the traditional view that small, primary access libraries are largely users of ILL, rather than important contributors to the effectiveness and efficiency of the national ILL system. This study was undertaken to test several commonly held beliefs regarding ILL system use by primary access libraries. Three hypotheses were developed. HI: Colorado and Wyoming primary access libraries comply with the recommended ILL guideline of adhering to a hierarchical structure, emphasizing local borrowing. H2: The closures of two Colorado Council of Medical Librarians (CCML) primary access libraries in 1996 resulted in twenty-three Colorado primary access libraries' borrowing more from their state resource library in 1997. H3: The number of subscriptions held by Colorado and Wyoming primary access libraries is positively correlated with the number of items they loan and negatively correlated with the number of items they borrow. The hypotheses were tested using the 1992 and 1997 DOCLINE and OCLC data of fifty-four health sciences libraries, including fifty primary access libraries, two state resource libraries, and two general academic libraries in Colorado and Wyoming. The ILL data were obtained electronically and analyzed using Microsoft Word 98, Microsoft Excel 98, and JMP 3.2.2. CCML primary access libraries comply with the recommended guideline to emphasize local borrowing by supplying each other with the majority of their ILLs, instead of overburdening libraries located at higher levels in the ILL hierarchy (H1). The closures of two CCML primary access libraries appear to have affected the entire ILL system, resulting in a greater volume of ILL activity for the state resource library and other DOCLINE libraries higher

  16. The experiences of a small Canadian petroleum company in the international arena

    International Nuclear Information System (INIS)

    Rooney, J.

    2002-01-01

    Equatorial Energy Inc. is a small Canadian company that has succeeded in the international world of oil exploration and production. The 5 year old company has grown from zero to 13,000 boe/d through its engagement in the acquisition, exploration and development of petroleum and natural gas in Western Canada and Indonesia. Finding costs are getting higher as domestic sedimentary basins mature. This results in higher decline rates and fewer opportunities for growth. However, the international energy sector has become more accessible to small- and medium-sized companies due to the removal of political barriers and better access to new technologies. The support of capital markets and international experience also contributes to greater success in accessing the international energy sector. 16 figs

  17. Purchasing cooperatives for small employers: performance and prospects.

    Science.gov (United States)

    Wicks, E K; Hall, M A

    2000-01-01

    Health insurance purchasing cooperatives were established in the early to mid-1990s for the purpose of making health insurance more affordable and accessible for small employers. Extensive interviews at six cooperatives reveal that while some cooperatives enrolled large numbers of small employers, most have won only small market shares and a number have struggled for survival, not always successfully. They have allowed small employers to offer individual employees choice of health plans, but none has been able to sustain lower prices than are available in the conventional market. Among the important impediments to their success are limited support from health plans and conflicts over the role of insurance agents.

  18. Accessible mathematics ten instructional shifts that raise student achievement

    CERN Document Server

    Leinwand, Steven

    2009-01-01

    Accessible Mathematics is Steven Leinwand's latest important book for math teachers. He focuses on the crucial issue of classroom instruction. He scours the research and visits highly effective classrooms for practical examples of small adjustments to teaching that lead to deeper student learning in math. Some of his 10 classroom-tested teaching shifts may surprise you and others will validate your thinking. But all will improve students' performance. Read Accessible Mathematics, try its 10 suggestions, and discover how minor shifts in teaching can put learning into high gear.

  19. Small satellites and their regulation

    CERN Document Server

    Jakhu, Ram S

    2014-01-01

    Since the launch of UoSat-1 of the University of Surrey (United Kingdom) in 1981, small satellites proved regularly to be useful, beneficial, and cost-effective tools. Typical tasks cover education and workforce development, technology demonstration, verification and validation, scientific and engineering research as well as commercial applications. Today the launch masses range over almost three orders of magnitude starting at less than a kilogram up to a few hundred kilograms, with budgets of less than US$ 100.00 and up to millions within very short timeframes of sometimes less than two years. Therefore each category of small satellites provides specific challenges in design, development and operations. Small satellites offer great potentials to gain responsive, low-cost access to space within a short timeframe for institutions, companies, regions and countries beyond the traditional big players in the space arena. For these reasons (particularly the low cost of construction, launch and operation), small (m...

  20. Investigation of the motion processes of wastewater in sewerage of high-rise buildings

    Directory of Open Access Journals (Sweden)

    Pomogaeva Valentina

    2018-01-01

    Full Text Available When designing, constructing and operating sewage pipelines in high-rise buildings, issues of failure-free operation of a network arise. Investigation of the processes of wastewater moving allows identifying problem areas during operation, assessing the possibility of obstructions and breakdowns of plumbing traps on the gravity drainage sections of the pipeline. The article performs the schemes of the water outflow from the floor sewer into the riser, including the places where the riser is bent, of air delivery to the working riser under the change of the direction of drain movement with the dropout line set-up, with the installation of an automatic anti-vacuum valve, with the installation of the ventilation pipeline. Investigations of the process of sewage waste flow in a sewage riser were carried out, in order to select the appropriate structure. The authors consider structure features of some sections of sewerage in high-rise buildings. The exhaustion value in the riser is determined from the rarefactions that occur below the compressed cross-section of the riser and the loss of the air flow pressure coming from the atmosphere into the riser during the deflooding of the liquid. Preventing the formation of obstructions and breakdowns of plumbing traps is an integral part of sewage networks.

  1. Investigation of the motion processes of wastewater in sewerage of high-rise buildings

    Science.gov (United States)

    Pomogaeva, Valentina; Metechko, Lyudmila; Prokofiev, Dmitry; Narezhnaya, Tamara

    2018-03-01

    When designing, constructing and operating sewage pipelines in high-rise buildings, issues of failure-free operation of a network arise. Investigation of the processes of wastewater moving allows identifying problem areas during operation, assessing the possibility of obstructions and breakdowns of plumbing traps on the gravity drainage sections of the pipeline. The article performs the schemes of the water outflow from the floor sewer into the riser, including the places where the riser is bent, of air delivery to the working riser under the change of the direction of drain movement with the dropout line set-up, with the installation of an automatic anti-vacuum valve, with the installation of the ventilation pipeline. Investigations of the process of sewage waste flow in a sewage riser were carried out, in order to select the appropriate structure. The authors consider structure features of some sections of sewerage in high-rise buildings. The exhaustion value in the riser is determined from the rarefactions that occur below the compressed cross-section of the riser and the loss of the air flow pressure coming from the atmosphere into the riser during the deflooding of the liquid. Preventing the formation of obstructions and breakdowns of plumbing traps is an integral part of sewage networks.

  2. An observational study of consumers' accessing of nutrition information in chain restaurants.

    Science.gov (United States)

    Roberto, Christina A; Agnew, Henry; Brownell, Kelly D

    2009-05-01

    In this observational study, we determined how frequently consumers accessed on-premises nutrition information provided at chain restaurants. The number of patrons entering and accessing nutrition information was recorded at 8 locations that were part of 4 major restaurant chains (McDonald's, Burger King, Starbucks, and Au Bon Pain). Only 6 (0.1%) of 4311 patrons accessed on-premises nutrition information before purchasing food. This very small percentage suggests that such information should be more prominently displayed, such as on restaurant menu boards, to help customers make informed decisions.

  3. An Observational Study of Consumers’ Accessing of Nutrition Information in Chain Restaurants

    Science.gov (United States)

    Agnew, Henry; Brownell, Kelly D.

    2009-01-01

    In this observational study, we determined how frequently consumers accessed on-premises nutrition information provided at chain restaurants. The number of patrons entering and accessing nutrition information was recorded at 8 locations that were part of 4 major restaurant chains (McDonald's, Burger King, Starbucks, and Au Bon Pain). Only 6 (0.1%) of 4311 patrons accessed on-premises nutrition information before purchasing food. This very small percentage suggests that such information should be more prominently displayed, such as on restaurant menu boards, to help customers make informed decisions. PMID:19299679

  4. Thermodynamic optimisation and computational analysis of irreversibilities in a small-scale wood-fired circulating fluidised bed adiabatic combustor

    CSIR Research Space (South Africa)

    Baloyi, J

    2014-06-01

    Full Text Available parameters on energy and exergy characteristics and exergy losses. International Journal of Energy Research 2006; 30: 203-219. [24] Ziebik A, stanek W. Energy and exergy system analysis of thermal improvements of blast-furnace plants. International... in the riser column of a pressurized circulating fluidized bed. International Journal of Energy Research 2006; 30: 149-162. [27] Cihan A, Hacihafizoglu O, Kahveci K. Energy-exergy analysis and modenization suggestions for a combined-cycle power plant...

  5. Principal component analysis in an experimental cold flow model of a fluid catalytic cracking unit by gammametry

    International Nuclear Information System (INIS)

    Araujo, Janeo Severino C. de; Dantas, Carlos Costa; Santos, Valdemir A. dos; Souza, Jose Edson G. de; Luna-Finkler, Christine L.

    2009-01-01

    The fluid dynamic behavior of riser of a cold flow model of a Fluid Catalytic Cracking Unit (FCCU) was investigated. The experimental data were obtained by the nuclear technique of gamma transmission. A gamma source was placed diametrically opposite to a detector in any straight section of the riser. The gas-solid flow through riser was monitored with a source of Americium-241 what allowed obtaining information of the axial solid concentration without flow disturbance and also identifying the dependence of this concentration profile with several independent variables. The MatLab R and Statistica R software were used. Statistica tool employed was the Principal Components Analysis (PCA), that consisted of the job of the data organization, through two-dimensional head offices to allow extract relevant information about the importance of the independent variables on axial solid concentration in a cold flow riser. The variables investigated were mass flow rate of solid, mass flow rate of gas, pressure in the riser base and the relative height in the riser. The first two components reached about 98 % of accumulated percentage of explained variance. (author)

  6. Oil production system

    Energy Technology Data Exchange (ETDEWEB)

    Ballantyne, J F

    1983-12-21

    A new oil producing system is proposed which consists of a group of underwater wells, an underwater riser and a floating storage facility for the production of the wells. The group of wells and the riser are interconnected through a manifold system in such a way that the production from any well or from the entire group of wells go to the base (foundation) of the riser. From above the riser is connected with the floating storage facility which is equipped, besides tanks for storing the well products, with a separation device for separating the oil and the accompanying gas. The gas is used as a fuel for producing electric power required by the dynamic positioning systems. The products from each well are tested by means of a regulable coupling controlled by means of a cable, which is passed from the surface through the riser. The wellhead equipment for the unslanted wells is mounted on a template previously installed on the sea floor. From the template the well products enter the riser through the manifold unit system.

  7. Why small-scale cannabis growers stay small: five mechanisms that prevent small-scale growers from going large scale.

    Science.gov (United States)

    Hammersvik, Eirik; Sandberg, Sveinung; Pedersen, Willy

    2012-11-01

    Over the past 15-20 years, domestic cultivation of cannabis has been established in a number of European countries. New techniques have made such cultivation easier; however, the bulk of growers remain small-scale. In this study, we explore the factors that prevent small-scale growers from increasing their production. The study is based on 1 year of ethnographic fieldwork and qualitative interviews conducted with 45 Norwegian cannabis growers, 10 of whom were growing on a large-scale and 35 on a small-scale. The study identifies five mechanisms that prevent small-scale indoor growers from going large-scale. First, large-scale operations involve a number of people, large sums of money, a high work-load and a high risk of detection, and thus demand a higher level of organizational skills than for small growing operations. Second, financial assets are needed to start a large 'grow-site'. Housing rent, electricity, equipment and nutrients are expensive. Third, to be able to sell large quantities of cannabis, growers need access to an illegal distribution network and knowledge of how to act according to black market norms and structures. Fourth, large-scale operations require advanced horticultural skills to maximize yield and quality, which demands greater skills and knowledge than does small-scale cultivation. Fifth, small-scale growers are often embedded in the 'cannabis culture', which emphasizes anti-commercialism, anti-violence and ecological and community values. Hence, starting up large-scale production will imply having to renegotiate or abandon these values. Going from small- to large-scale cannabis production is a demanding task-ideologically, technically, economically and personally. The many obstacles that small-scale growers face and the lack of interest and motivation for going large-scale suggest that the risk of a 'slippery slope' from small-scale to large-scale growing is limited. Possible political implications of the findings are discussed. Copyright

  8. Small millet farmers increase yields through participatory varietal

    International Development Research Centre (IDRC) Digital Library (Canada)

    When farmers adopt a variety along with ones they already ... Increased access to quality seed of promising ... Figure 1: Potential increases in yield of small millet preferred varieties. 0. 200 ... terms of both product (farmers preferred varieties ...

  9. Financing Small Businesses: From Venture Capital to Crowdfunding

    Directory of Open Access Journals (Sweden)

    Herciu Mihaela

    2017-08-01

    Full Text Available Startups and small businesses are facing many challenges in terms of financing their activities. These types of companies do not have the possibility to access capital market or to make IPO or to borrow money from banks like big, mature or well-known companies (who were at their beginnings startups or small businesses. They have to find different sources for financing their ideas/products/services that are in many cases very risky, hazardous or to ambitious. But, fortunately, the financing alternative for these companies have evolved during the last post crisis years. They have possibility to find some investors that are willing to invest in a non-name company by accessing crowdfunding platforms, impress angel investors, or attracting venture capital. All that in order to develop their business and to become a unicorn or to have a great exit.

  10. Small and Medium Enterprises and Biopharmaceutical Innovations ...

    African Journals Online (AJOL)

    Small and Medium Enterprises and Biopharmaceutical Innovations in Africa: ... through biotechnological processes with links to biological sources especially those of live ... There are more than 500 biopharmaceutical products that have been ... By Country · List All Titles · Free To Read Titles This Journal is Open Access.

  11. A comparison of Frequency Domain Multiple Access (FDMA) and Time Domain Multiple Access (TDMA) approaches to satellite service for low data rate Earth stations

    Science.gov (United States)

    Stevens, G.

    1983-01-01

    A technological and economic assessment is made of providing low data rate service to small earth stations by satellite at Ka-band. Various Frequency Domain Multiple Access (FDMA) and Time Domain Multiple Access (TDMA) scenarios are examined and compared on the basis of cost to the end user. Very small stations (1 to 2 meters in diameter) are found not to be viable alternatives to available terrestrial services. However, medium size (3 to 5 meters) earth stations appear to be very competitive if a minimum throughput of about 1.5 Mbs is maintained. This constrains the use of such terminals to large users and shared use by smaller users. No advantage was found to the use of FDMA. TDMA had a slight advantage from a total system viewpoint and a very significant advantage in the space segment (about 1/3 the required payload weight for an equivalent capacity).

  12. Technologie pour le forage scientifique en eau très profonde au XXIe siècle Deepwater Technology for Scientific Drilling in the 21st Century

    Directory of Open Access Journals (Sweden)

    Sparks C.

    2006-11-01

    Full Text Available Le présent article aborde les slimline risers et les systèmes de forage minier qui sont deux domaines technologiques dont le potentiel doit permettre d'améliorer le forage et le carottage scientifiques en eau très profonde au cours du XXIe siècle. Cet article présente les avantages et les inconvénients des slimline risers, par rapport aux risers de forage utilisés par l'industrie pétrolière. Le potentiel de matériaux nouveaux est évoqué. Des analyses préliminaires de slimline risers fabriqués de différents matériaux (acier, titane, aluminium et composite pour forage scientifique par 4 000 m de profondeur d'eau sont présentées. La seconde partie de l'article aborde les moyens d'adapter les systèmes de forage minier aux grands fonds. This paper addresses slimline riser systems and mining drilling systems which are two items of technology that have the potential to improve scientific drilling and coring in deep water in the 21st century. The paper presents the advantages and disadvantages of drilling with a slimline riser, compared to an oil industry riser. The potential of new materials are discussed. Preliminary analyses of slimline risers made from different materials (steel, titanium, aluminium and composite for 4000 m of water are presented. In the second part of the paper, ways of adapting mining systems to deepwater are discussed.

  13. Resources access needs and capabilities as mediators of the relationship between VC firm size and syndication

    NARCIS (Netherlands)

    E. Verwaal (Ernst); J. Bruining (Hans); D.M. Wright (Mike); S. Manigart (Sophie); A. Lockett (Andy)

    2010-01-01

    textabstractDrawing from the resource-based view and transaction costs economics, we develop a theoretical framework to explain why small and large firms face different levels of resource access needs and resource access capabilities, which mediate the relationship between firm size and hybrid

  14. Urban Structure Matters, Even in a Small Town

    DEFF Research Database (Denmark)

    Næss, Petter; Jensen, Ole B.

    2002-01-01

    A recent study in Frederikshavn, Denmark, shows that urban structural variables influence travel behavior also in a small town of around 30 000 inhabitants. As one might expect, socioeconomic and attitudinal factors play a role for the respondents? traveling patterns. But also when controlling...... are confirmed in qualitative interviews. The distance from the residence to the downtown area is a key factor influencing the accessibility to a number of facility types. These differences in accessibility result in corresponding differences in the actual traveling distances and modal split....

  15. Catwell and Sherdaps for deep-water production fields

    Energy Technology Data Exchange (ETDEWEB)

    Hopper, H.P.; Rey, R. [Cameron, 34 - Beziers (France)

    2000-07-01

    The names Catwell and SherDaps are derived from: - Catenary Well - Subsea Horizontal Extended Reach Drilling And Production System. Both systems use the technique of being able to drill a well in deep-water either through a platform catenary carrier pipe or a catenary drilling riser. They also offer, in addition, significant advantages when drilling into shallow reservoirs and the ability to enhance production using platform artificial lift systems or easily serviceable pumps either in the well or at the mud-line. Catwell is a platform system with surface wellheads/trees whereas SherDaps uses a group of subsea wellheads/trees/BOP's that are accessible from one permanent catenary drilling riser. Both systems allow drilling/completing and future well intervention from a central location that otherwise would have required several drilling centres (i.e. platforms or subsea) if the conventional approach was followed. It is envisaged that well targets close to a platform will use well conductors possibly with mud-line wellheads, then Catwell to reach the medium range well targets and SherDaps for long range wells. It is considered that this arrangement would allow a single surface drilling/ production centre to have access to well targets giving a foot print range of up to a 20 km diameter. The total Capex savings on a Deep-water Field Development could be in the region of $200 m on a $1 billion development. Opex will be lower with the ability from the drilling center to quickly access any problem well and rectify any faults, minimising lost production. (authors)

  16. Fast distributed strategic learning for global optima in queueing access games

    KAUST Repository

    Tembine, Hamidou

    2014-01-01

    In this paper we examine combined fully distributed payoff and strategy learning (CODIPAS) in a queue-aware access game over a graph. The classical strategic learning analysis relies on vanishing or small learning rate and uses stochastic

  17. Direct access: how is it working?

    Science.gov (United States)

    Turner, S; Ross, M

    2017-02-10

    Aim The aim of this study was to identify and survey dental hygienists and therapists working in direct access practices in the UK, obtain their views on its benefits and disadvantages, establish which treatments they provided, and what barriers they had encountered.Method The study used a purposive sample of GDC-registered hygienists and therapists working in practices offering direct access, identified through a 'Google' search. An online survey was set up through the University of Edinburgh, and non-responses followed up by post.Results The initial search identified 243 individuals working in direct access practices. Where a practice listed more than one hygienist/therapist, one was randomly selected. This gave a total of 179 potential respondents. Eighty-six responses were received, representing a response rate of 48%. A large majority of respondents (58, 73%) were favourable in their view of the GDC decision to allow direct access, and most thought advantages outnumbered disadvantages for patients, hygienists, therapists and dentists. There were no statistically significant differences in views between hygienists and therapists. Although direct access patients formed a small minority of their caseload for most respondents, it is estimated that on average respondents saw approximately 13 per month. Treatment was mainly restricted to periodontal work, irrespective of whether the respondent was singly or dually qualified. One third of respondents reported encountering barriers to successful practice, including issues relating to teamwork and dentists' unfavourable attitudes. However, almost two thirds (64%) felt that direct access had enhanced their job satisfaction, and 45% felt their clinical skills had increased.Discussion Comments were mainly positive, but sometimes raised worrying issues, for example in respect to training, lack of dental nurse support and the limited availability of periodontal treatment under NHS regulations.

  18. Small farmers and deforestation in Amazonia

    Science.gov (United States)

    Brondízio, Eduardo S.; Cak, Anthony; Caldas, Marcellus M.; Mena, Carlos; Bilsborrow, Richard; Futemma, Celia T.; Ludewigs, Thomas; Moran, Emilio F.; Batistella, Mateus

    This chapter discusses the relationship between small farmers' land use and deforestation, with particular attention paid to the past 30 years of Amazonian colonization in Brazil and Ecuador. Our analysis calls attention to common features uniting different social groups as small farmers (e.g., social identity, access to land and resources, technology, market, and credit), as well as the variability between small farmers in terms of time in the region (from native populations to recent colonists), contribution to regional deforestation, types of land use systems. At a regional level, small farmers contribute to the majority of deforestation events, but are responsible for only a fraction of the total deforested area in Amazonia. We discuss three misconceptions that have been used to define small farmers and their contribution to the regional economy, development, and deforestation: (1) small farmers have backward land use systems associated with low productivity and extensive deforestation and subsistence production, (2) small farmers contribute to Amazonian deforestation as much as large farmers, and (3) small farmers, particularly colonist farmers, follow an inexorable path of deforestation unless curbed by government action. We conclude the chapter discussing their growing regional importance and the need for more inclusive public policies concerning infrastructure and services and valorization of resources produced in rural areas of Amazonia.

  19. Moving Out of the Office: Removing Barriers to Access to Psychiatrists

    OpenAIRE

    Paris, Joel; Goldbloom, David; Kurdyak, Paul

    2015-01-01

    Our paper offers a perspective on barriers to access to psychiatric care. Research shows that access depends not simply on the total number of trained specialists but also on their kind of practice. In some large cities, some practitioners follow a small number of patients in long-term psychotherapy, a practice supported by government insurance, which places no limits on the number of sessions or treatment duration. The problem is that long-term psychotherapy, despite a rich tradition in psyc...

  20. Collaborative Indoor Access Point Localization Using Autonomous Mobile Robot Swarm.

    Science.gov (United States)

    Awad, Fahed; Naserllah, Muhammad; Omar, Ammar; Abu-Hantash, Alaa; Al-Taj, Abrar

    2018-01-31

    Localization of access points has become an important research problem due to the wide range of applications it addresses such as dismantling critical security threats caused by rogue access points or optimizing wireless coverage of access points within a service area. Existing proposed solutions have mostly relied on theoretical hypotheses or computer simulation to demonstrate the efficiency of their methods. The techniques that rely on estimating the distance using samples of the received signal strength usually assume prior knowledge of the signal propagation characteristics of the indoor environment in hand and tend to take a relatively large number of uniformly distributed random samples. This paper presents an efficient and practical collaborative approach to detect the location of an access point in an indoor environment without any prior knowledge of the environment. The proposed approach comprises a swarm of wirelessly connected mobile robots that collaboratively and autonomously collect a relatively small number of non-uniformly distributed random samples of the access point's received signal strength. These samples are used to efficiently and accurately estimate the location of the access point. The experimental testing verified that the proposed approach can identify the location of the access point in an accurate and efficient manner.

  1. Collaborative Indoor Access Point Localization Using Autonomous Mobile Robot Swarm

    Directory of Open Access Journals (Sweden)

    Fahed Awad

    2018-01-01

    Full Text Available Localization of access points has become an important research problem due to the wide range of applications it addresses such as dismantling critical security threats caused by rogue access points or optimizing wireless coverage of access points within a service area. Existing proposed solutions have mostly relied on theoretical hypotheses or computer simulation to demonstrate the efficiency of their methods. The techniques that rely on estimating the distance using samples of the received signal strength usually assume prior knowledge of the signal propagation characteristics of the indoor environment in hand and tend to take a relatively large number of uniformly distributed random samples. This paper presents an efficient and practical collaborative approach to detect the location of an access point in an indoor environment without any prior knowledge of the environment. The proposed approach comprises a swarm of wirelessly connected mobile robots that collaboratively and autonomously collect a relatively small number of non-uniformly distributed random samples of the access point’s received signal strength. These samples are used to efficiently and accurately estimate the location of the access point. The experimental testing verified that the proposed approach can identify the location of the access point in an accurate and efficient manner.

  2. Fast reactors as a solution for future small-scale nuclear energy

    International Nuclear Information System (INIS)

    Kudryavtseva, A.; Danilenko, K.; Dorofeev, K.

    2013-01-01

    Small nuclear power plants can provide a future platform for decentralized energy supply providing better levels of accessibility, safety and environmental friendliness. The optimal solution for SMR deployment is fast reactors with inherent safety. To compete alternative solutions SMRs must exhibit some evident advantages in: safety, technology, and economic. Small modular reactors with lead-bismuth coolant (SVBR-100) under development in Russia can be a prospective solution for future small and decentralized energy

  3. Open Access Publishing in High-Energy Physics: the SCOAP(3) Initiative

    CERN Document Server

    Mele, Salvatore

    2010-01-01

    Scholarly communication in High-Energy Physics (HEP) shows traits very similar to Astronomy and Astrophysics: pervasiveness of Open Access to preprints through community-based services; a culture of openness and sharing among its researchers; a compact number of yearly articles published by a relatively small number of journals which are dear to the community. These aspects have led HEP to spearhead an innovative model for the transition of its scholarly publishing to Open Access. The Sponsoring Consortium for Open Access Publishing in Particle Physics (SCOAP(3)) aims to be a central body to finance peer-review service rather than the purchase of access to information as in the traditional subscription model, with all articles in the discipline eventually available in Open Access. Sustainable funding to SCOAP(3) would come from libraries, library consortia and HEP funding agencies, through a re-direction of funds currently spent for subscriptions to HEP journals. This paper presents the cultural and bibliomet...

  4. Financing Small Businesses: From Venture Capital to Crowdfunding

    OpenAIRE

    Herciu Mihaela

    2017-01-01

    Startups and small businesses are facing many challenges in terms of financing their activities. These types of companies do not have the possibility to access capital market or to make IPO or to borrow money from banks like big, mature or well-known companies (who were at their beginnings startups or small businesses). They have to find different sources for financing their ideas/products/services that are in many cases very risky, hazardous or to ambitious. But, fortunately, the financing a...

  5. [Premalignant conditions of the small bowel].

    Science.gov (United States)

    Drastich, P

    2013-01-01

    Small intestinal dysplastic lesions are rare and difficult to detect before they progress to cancer. New investigative modalities, such as capsule endoscopy and doubleballoon enteroscopy, are very promising in search for premalignant lesions. Screening patients at high-risk for small bowel neoplasia is the only sensible approach. Duodenal adenoma represents the most easily accessible tumors with the possibility of curative endoscopic resection. Due to the strong association of the small bowel and colonic adenomas, it is always necessary to perform colonoscopy. In young patients, the exclusion of familial polyposis by genetic testing is always mandatory. Patients with celiac disease are especially at risk of developing nonHodgkins lymphomas and adenocarcinomas. There is a high-risk of ampuloma and other adenomas in patients with familial adenomatous polyposis. Patients with prolonged and complicated course of Crohns disease, Peutz Jeghers syndrome and patients with ileoanal pouch have higher risk of adenocarcinoma of the small intestine.

  6. Accessible Knowledge - Knowledge on Accessibility

    DEFF Research Database (Denmark)

    Kirkeby, Inge Mette

    2015-01-01

    Although serious efforts are made internationally and nationally, it is a slow process to make our physical environment accessible. In the actual design process, architects play a major role. But what kinds of knowledge, including research-based knowledge, do practicing architects make use of when...... designing accessible environments? The answer to the question is crucially important since it affects how knowledge is distributed and how accessibility can be ensured. In order to get first-hand knowledge about the design process and the sources from which they gain knowledge, 11 qualitative interviews...... were conducted with architects with experience of designing for accessibility. The analysis draws on two theoretical distinctions. The first is research-based knowledge versus knowledge used by architects. The second is context-independent knowledge versus context-dependent knowledge. The practitioners...

  7. Access time optimization of SRAM memory with statistical yield constraint

    NARCIS (Netherlands)

    Doorn, T.S.; Maten, ter E.J.W.; Di Bucchianico, A.; Beelen, T.G.J.; Janssen, H.H.J.M.

    2012-01-01

    A product may fail when design parameters are subject to large deviations. To guarantee yield one likes to determine bounds on the parameter range such that the fail probability P_fail is small. For Static Random Access Memory (SRAM) characteristics like Static Noise Margin and Read Current,

  8. Nudge to nobesity I: Minor changes in accessibility decrease food intake

    Directory of Open Access Journals (Sweden)

    Paul Rozin

    2011-06-01

    Full Text Available Very small but cumulated decreases in food intake may be sufficient to erase obesity over a period of years. We examine the effect of slight changes in the accessibility of different foods in a pay-by-weight-of-food salad bar in a cafeteria serving adults for the lunch period. Making a food slightly more difficult to reach (by varying its proximity by about 10 inches or changing the serving utensil (spoon or tongs modestly but reliably reduces intake, in the range of 8-16%. Given this effect, it is possible that making calorie-dense foods less accessible and low-calorie foods more accessible over an extended period of time would result in significant weight loss.

  9. Financing and disseminating small energy systems in rural areas

    International Nuclear Information System (INIS)

    Waddle, D.B.; Perlack, R.D.

    1992-01-01

    The viability of small energy systems, primarily photovoltaic systems, is discussed as an alternative for rural electrification via traditional grid extension. A dissemination model that incorporates financing to allow access to a much larger population of users and technology support (e.g. training for sales and service and small business development) is described. The experience of two successful programs is presented to illustrate the keys to effective program development and implementation. (author)

  10. Monitoring catalyst flow rate in a FCC cold pilot unity by gamma ray transmission measurements

    International Nuclear Information System (INIS)

    Brito, Marcio F.P.; Netto, Wilson F.S.; Miranda, Marcia V.F.E.S.; Junior, Isacc A.S.; Dantas, Carlos C.; Melo, Silvio B.; Lima, Emerson A.O.

    2013-01-01

    A model for monitoring catalyst mass flow in riser of Fluid Catalytic Cracking - FCC, pilot unity as a function of air flow and solid injection is proposed. The fluidized FCC- catalyst bed system is investigated in an experimental setup the Cold Pilot Unity - CPU by means of gamma ray transmission measurements. Riser in CPU simulates the reactor in FCC process. By automation control air flow is instrumentally measured in riser and the solid injection is manually controlled by valve adjusting. Keeping a constant solid injection, catalyst level at the return column was measured by gamma transmission for several air flow values in riser. The operational condition reached a steady state regime before given to setup a new air flow value. A calibration of catalyst level as a function of air flow in riser is calculated, therefore, a model for solid feed rate is derived. Recent published work evaluates solid concentration in riser of the CPU by means of gamma ray transmission, and a correlation with air velocity is obtained. In this work, the model for solid feed rate was further investigated by carrying out experiments to measure catalyst concentration at the same air flow values. These experiments lead to a model for monitoring catalyst flow in riser as function of solid feed rate and air flow. Simulation with random numbers produced with Matlab software allows to define validation criteria for the model parameters. (author)

  11. Characterization of porous materials by small-angle scattering

    Indian Academy of Sciences (India)

    With the availability of ultra small-angle scattering instruments, one can investigate porous materials in the sub-micron length scale. Because of the increased accessible length scale vis-a-vis the multiple scattering effect, conventional data analysis procedures based on single scattering approximation quite often fail.

  12. Performance Issues Related to Web Service Usage for Remote Data Access

    International Nuclear Information System (INIS)

    Pais, V. F.; Stancalie, V.; Mihailescu, F. A.; Totolici, M. C.

    2008-01-01

    Web services are starting to be widely used in applications for remotely accessing data. This is of special interest for research based on small and medium scale fusion devices, since scientists participating remotely to experiments are accessing large amounts of data over the Internet. Recent tests were conducted to see how the new network traffic, generated by the use of web services, can be integrated in the existing infrastructure and what would be the impact over existing applications, especially those used in a remote participation scenario

  13. Performance indicators for SMEs accessing EU funds

    OpenAIRE

    Popa Adina-Simona

    2013-01-01

    Being the best supporters of national economies Small and Medium Sized Enterprises are actively searching alternative sources of finance for sustaining their goals and their performances. European Union is sustaining the SMEs access to finance by direct funding: grants from the European Commission and indirect funding: financial intermediaries in the SMEs origin country. Considering the importance of SMEs for national and European economy we will analyze the relationship between the EU fundin...

  14. Small wind turbine purchasing guide : off-grid, residential, farm and small business applications

    International Nuclear Information System (INIS)

    2008-11-01

    Consumer interest in the environment and the economic advantages of using wind power are now driving interest in smaller wind turbines that range from micro battery-charging models to 300 kW tower-mounted turbines. Smaller turbines are also becoming increasingly accessible through major retail outlets. This guide discussed basic issues surrounding the purchasing, selection and installation of smaller wind turbines. Guidance related to site selection, permitting and approvals was provided, as well as recommendations related to maintenance and system performance. Information related to compliance, safety and setback and zoning restrictions was also presented. The guide was divided into 5 chapters: (1) an introduction to small wind turbines, (2) assessing site-specific expectations, (3) purchasing and permitting, (4) installation, operation and maintenance, and (6) a permitting checklist for small wind customers. Financial incentives for defraying the capital costs of small wind turbines were discussed, and guidance for determining electrical requirements was also provided. A glossary was included, as well as a list of local wind energy contractor and dealers. 3 tabs., 10 figs

  15. Monitoring of mass flux of catalyst FCC in a Cold Pilot Unit by gamma radiation transmission; Monitoramento da taxa de fluxo do catalisador FCC em uma unidade piloto a frio por medicao de transmissao gama

    Energy Technology Data Exchange (ETDEWEB)

    Brito, Marcio Fernando Paixao de

    2014-09-01

    This paper proposes a model for monitoring the mass flow of catalyst FCC - Fluid Catalytic Cracking - in a CPU - Cold Pilot unit - due to the injection of air and solid by gamma radiation transmission. The CPU simplifies the process of FCC, which is represented by the catalyst cycle, and it was constructed of acrylic, so that the flow can be visualized. The CPU consists of riser separation chamber and return column, and simulates the riser reactor of the FCC process. The catalyst is injected into the column back to the base of the riser, an inclined tube, where the compressed air means that there fluidization along the riser. When the catalyst comes in the separation chamber, the solid phase is sent to the return column, and the gas phase exits the system through one of the four cyclones at the top of the separation chamber. The transmission gamma of measures will be made by means of three test sections that have source and detector shielded. Pressure drop in the riser measurements are made through three pressure gauges positioned on the riser. The source used was Am-241 gamma ray with energy of 60 keV, and detector used was a scintillator of NaI (Tl) of 2 {sup x} 2{sup .} Measures the mass flow of catalyst are made by varying the seal of the catalyst, and density of solid in the riser because with the combination of these measures can determine the speed of the catalyst in the riser. The results show that the transmission gamma is a suitable technique for monitoring the flow of catalyst, flow model in CPU is annular, tomography third generation is more appropriate to study the CPU and the density variation in circulation in the CPU decreases linearly with increasing air flow. (author)

  16. Monitoring of mass flux of catalyst FCC in a Cold Pilot Unit by gamma radiation transmission

    International Nuclear Information System (INIS)

    Brito, Marcio Fernando Paixao de

    2014-01-01

    This paper proposes a model for monitoring the mass flow of catalyst FCC - Fluid Catalytic Cracking - in a CPU - Cold Pilot unit - due to the injection of air and solid by gamma radiation transmission. The CPU simplifies the process of FCC, which is represented by the catalyst cycle, and it was constructed of acrylic, so that the flow can be visualized. The CPU consists of riser separation chamber and return column, and simulates the riser reactor of the FCC process. The catalyst is injected into the column back to the base of the riser, an inclined tube, where the compressed air means that there fluidization along the riser. When the catalyst comes in the separation chamber, the solid phase is sent to the return column, and the gas phase exits the system through one of the four cyclones at the top of the separation chamber. The transmission gamma of measures will be made by means of three test sections that have source and detector shielded. Pressure drop in the riser measurements are made through three pressure gauges positioned on the riser. The source used was Am-241 gamma ray with energy of 60 keV, and detector used was a scintillator of NaI (Tl) of 2 x 2 . Measures the mass flow of catalyst are made by varying the seal of the catalyst, and density of solid in the riser because with the combination of these measures can determine the speed of the catalyst in the riser. The results show that the transmission gamma is a suitable technique for monitoring the flow of catalyst, flow model in CPU is annular, tomography third generation is more appropriate to study the CPU and the density variation in circulation in the CPU decreases linearly with increasing air flow. (author)

  17. Assessment of the impact of VIV (Vortex Induced Vibrations) on closely spaced production jumpers

    Energy Technology Data Exchange (ETDEWEB)

    Saint-Marcoux, Jean-Francois; Legras, Jean-Luc; Bastos, Renato; Rochereau, Max [Acergy, London (United Kingdom)

    2009-12-19

    Brazilian deep water projects require new concepts both for Early Production and Extended Tests Systems for which Floating Production units with smaller hulls are cost-efficient. Further more the Brazilian environment precludes spread mooring. This results in closely spaced riser configurations. Acergy has investigated the issue of interference between closely spaced risers for a few years in practice (bundle Riser Towers, SCR's), experimentally (with Scripps Institution of Oceanography), and with CFD (with Texas A and M University). The result has been in 2008 the inclusion of the Blevins model in commercially available software. Nevertheless the assessment of the impact of VIV of the upstream riser remained elusive. Measurements performed in 2007 confirmed that the wake behind a cylinder under VIV was expanded and the hydrodynamic forces on the downstream riser strongly affected when the upstream cylinder was undergoing Vortex Induced Vibrations (VIV). Measurements conducted in 2008 up to a Reynolds number of 140 000 appear to validate an engineering approach of the impact of VIV that can be readily included in commercially available software for design engineering purpose. The paper describes the experimental measurements, the proposed wake model, comparison of the measurements and model. Application to the design of deep water riser and jumper systems is also included. (author)

  18. Demand access communications for TDRSS users

    Science.gov (United States)

    Zillig, David; Weinberg, Aaron; Mcomber, Robert

    1994-01-01

    The Tracking and Data Relay Satellite System (TDRSS) has long been used to provide reliable low and high-data rate relay services between user spacecraft in Earth orbit and the ground. To date, these TDRSS services have been implemented via prior scheduling based upon estimates of user needs and mission event timelines. While this approach may be necessary for large users that require greater amounts of TDRSS resources, TDRSS can potentially offer the planned community of smaller science missions (e.g., the small explorer missions), and other emerging users, the unique opportunity for services on demand. In particular, innovative application of the existing TDRSS Multiple Access (MA) subsystem, with its phased array antenna, could be used to implement true demand access services without modification to either the TDRSS satellites or the user transponder, thereby introducing operational and performance benefits to both the user community and the Space Network. In this paper, candidate implementations of demand access service via the TDRSS MA subsystem are examined in detail. Both forward and return link services are addressed and a combination of qualitative and quantitative assessments are provided. The paper also identifies further areas for investigation in this ongoing activity that is being conducted by GSFC/Code 531 under the NASA Code O Advanced Systems Program.

  19. Data: Big and Small.

    Science.gov (United States)

    Jones-Schenk, Jan

    2017-02-01

    Big data is a big topic in all leadership circles. Leaders in professional development must develop an understanding of what data are available across the organization that can inform effective planning for forecasting. Collaborating with others to integrate data sets can increase the power of prediction. Big data alone is insufficient to make big decisions. Leaders must find ways to access small data and triangulate multiple types of data to ensure the best decision making. J Contin Educ Nurs. 2017;48(2):60-61. Copyright 2017, SLACK Incorporated.

  20. Access to flexible working and informal care

    OpenAIRE

    Bryan, Mark L.

    2011-01-01

    We use matched employer-employee data to explore the relationship between employees' access to flexible working arrangements and the amount of informal care they provide to sick or elderly friends and relatives. Flexitime and the ability to reduce working hours are each associated with about 10% more hours of informal care, with effects concentrated among full-time workers providing small amounts of care. The wider workplace environment beyond formal flexible work also appears to facilitate c...

  1. Access to capital--a growing concern.

    Science.gov (United States)

    Carlson, Donald A

    2004-01-01

    Access to capital over the next ten years will be one of the biggest challenges healthcare organizations will face as they strive to remain competitive and serve their communities. Meeting the growing needs for capital will require a disciplined and honest assessment of the capital sources that will be available and the best ways of positioning an organization to maximize their uses. It is incumbent on chief executive officers and other senior leaders to create a disciplined process for allocating capital and conveying how that process will be linked to the organization's strategic plan. All of the credit constituencies "buying" healthcare need to fully understand how the organization is positioning itself for future growth and success, and detailed bond marketing plans need to be implemented well before the actual sale of a new bond issue. Large and small healthcare providers will have sufficient access to capital in the future if investors believe that senior hospital executives have a credible plan and are disciplined enough to execute it.

  2. Small employers and self-insured health benefits: too small to succeed?

    Science.gov (United States)

    Yee, Tracy; Christianson, Jon B; Ginsburg, Paul B

    2012-07-01

    Over the past decade, large employers increasingly have bypassed traditional health insurance for their workers, opting instead to assume the financial risk of enrollees' medical care through self-insurance. Because self-insurance arrangements may offer advantages--such as lower costs, exemption from most state insurance regulation and greater flexibility in benefit design--they are especially attractive to large firms with enough employees to spread risk adequately to avoid the financial fallout from potentially catastrophic medical costs of some employees. Recently, with rising health care costs and changing market dynamics, more small firms--100 or fewer workers--are interested in self-insuring health benefits, according to a new qualitative study from the Center for Studying Health System Change (HSC). Self-insured firms typically use a third-party administrator (TPA) to process medical claims and provide access to provider networks. Firms also often purchase stop-loss insurance to cover medical costs exceeding a predefined amount. Increasingly competitive markets for TPA services and stop-loss insurance are making self-insurance attractive to more employers. The 2010 national health reform law imposes new requirements and taxes on health insurance that may spur more small firms to consider self-insurance. In turn, if more small firms opt to self-insure, certain health reform goals, such as strengthening consumer protections and making the small-group health insurance market more viable, may be undermined. Specifically, adverse selection--attracting sicker-than-average people--is a potential issue for the insurance exchanges created by reform.

  3. Usable and accessible websites in SMEs. Challenges for the future

    Directory of Open Access Journals (Sweden)

    Ana Castillo-Díaz, Ph. D.

    2010-01-01

    Full Text Available In an increasingly competitive environment in which Internet occupies a prominent place, transferring a brand from the offline to the online environment has become a vital issue for companies. Usability and accessibility have become crucial to enable adequate online brand communication. Ensuring websites are usable and accessible will facilitate web navigation, will improve the company’s image, and will favour loyalty towards the brand.This article presents the results of an investigation measuring the extent to what small and medium enterprises (SMEs employ usability and accessibility as supporting pillars of brand in the online environment to communicate with their audiences. The results indicate that usability is in fact taken into account by SMEs, but it is seen more as a technological element than as a promotion tool for the brand. Accessibility, on the other hand, is of secondary concern in the design of websites analysed, since they are not certified by any standard and are not fully accessible. Thus, it can be argued that the concern to transmit the brand online is incipient but, currently, SMEs do not take advantage of all the potential offered by the Web.

  4. Access Request Trustworthiness in Weighted Access Control Framework

    Institute of Scientific and Technical Information of China (English)

    WANG Lun-wei; LIAO Xiang-ke; WANG Huai-min

    2005-01-01

    Weighted factor is given to access control policies to express the importance of policy and its effect on access control decision. According to this weighted access control framework, a trustworthiness model for access request is also given. In this model, we give the measure of trustworthiness factor to access request, by using some idea of uncertainty reasoning of expert system, present and prove the parallel propagation formula of request trustworthiness factor among multiple policies, and get the final trustworthiness factor to decide whether authorizing. In this model, authorization decision is given according to the calculation of request trustworthiness factor, which is more understandable, more suitable for real requirement and more powerful for security enhancement than traditional methods. Meanwhile the finer access control granularity is another advantage.

  5. Addressing geographic access barriers to emergency care services: a national ecologic study of hospitals in Brazil

    OpenAIRE

    Rocha, Thiago Augusto Hernandes; da Silva, N?bia Cristina; Amaral, Pedro Vasconcelos; Barbosa, Allan Claudius Queiroz; Rocha, Jo?o Victor Muniz; Alvares, Viviane; de Almeida, Dante Grapiuna; Thum?, Elaine; Thomaz, Erika B?rbara Abreu Fonseca; de Sousa Queiroz, Rejane Christine; de Souza, Marta Rovery; Lein, Adriana; Lopes, Daniel Paulino; Staton, Catherine A.; Vissoci, Jo?o Ricardo Nickenig

    2017-01-01

    Background Unequal distribution of emergency care services is a critical barrier to be overcome to assure access to emergency and surgical care. Considering this context it was objective of the present work analyze geographic access barriers to emergency care services in Brazil. A secondary aim of the study is to define possible roles to be assumed by small hospitals in the Brazilian healthcare network to overcome geographic access challenges. Methods The present work can be classified as a c...

  6. Open Access Publishing in High-Energy Physics: the SCOAP3 Initiative

    Science.gov (United States)

    Mele, S.

    2010-10-01

    Scholarly communication in High-Energy Physics (HEP) shows traits very similar to Astronomy and Astrophysics: pervasiveness of Open Access to preprints through community-based services; a culture of openness and sharing among its researchers; a compact number of yearly articles published by a relatively small number of journals which are dear to the community. These aspects have led HEP to spearhead an innovative model for the transition of its scholarly publishing to Open Access. The Sponsoring Consortium for Open Access Publishing in Particle Physics (SCOAP) aims to be a central body to finance peer-review service rather than the purchase of access to information as in the traditional subscription model, with all articles in the discipline eventually available in Open Access. Sustainable funding to SCOAP would come from libraries, library consortia and HEP funding agencies, through a re-direction of funds currently spent for subscriptions to HEP journals. This paper presents the cultural and bibliometric factors at the roots of SCOAP and the current status of this worldwide initiative.

  7. Environmental Impact of Tourism and Air Transport on the Sustainable Development of Small Island Developing States

    Science.gov (United States)

    1999-01-01

    The United Nations General Assembly recognized that many small island developing countries were confronted with compelling factors such as their smallness in size, susceptibility and vulnerability to natural disasters, remoteness of access and geogra...

  8. Comparison of vapor sampling system (VSS) and in situ vapor sampling (ISVS) methods on Tanks C-107, BY-108, and S-102. Revision 1

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Edwards, J.A.; Evans, J.C.

    1996-08-01

    This report discusses comparison tests for two methods of collecting vapor samples from the Hanford Site high-level radioactive waste tank headspaces. The two sampling methods compared are the truck-mounted vapor sampling system (VSS) and the cart-mounted in-situ vapor sampling (ISVS). Three tanks were sampled by both the VSS and ISVS methods from the same access risers within the same 8-hour period. These tanks have diverse headspace compositions and they represent the highest known level of several key vapor analytes

  9. Promoting small towns for rural development: a view from Nepal.

    Science.gov (United States)

    Bajracharya, B N

    1995-06-01

    Two small villages in Nepal are the subjects of case studies that illustrate the role of small towns in provision of services, employment, and market operations. Some general findings are that small towns act as service centers for distribution of basic essential goods such as food grains, salt, kerosene, and fabric for hill and mountain areas. The role of small towns as market centers and in the provision of employment is limited. In resource-poor areas small towns are less diversified. Towns with agricultural surpluses are more developed. Small hill towns satisfy consumption rather than production needs. The growth of rural areas and towns in rural areas in Nepal is dependent on arable land and levels of production in hill areas. Limited land and low levels of production have an adverse impact. Movement of people, goods, and services is limited by difficult terrain and lack of access to good roads. Variability in access to off-farm jobs and services available in small towns varies with ethnicity and place of residence. The best development strategy for small towns in Nepal is market-oriented territorial development, which retains surpluses in the local area and integrates markets in the larger economy. The strategy would decentralize planning into small territorial units that include both small towns and groups of villages, provide institutional support for the rural poor, expand off-farm employment, and include investment in region-serving functions. Subsistence agriculture needs to include diversification of high value cash crops based on local comparative advantage suitable for hill climate and terrain. Small farmers must produce both cash and subsistence crops. Government should provide market space and paved areas, weighing facilities, and overnight storage facilities. Products would be processed at the village level. Subdistricts must be established according to spatial and social linkages between villages and the service center and coordinated at the

  10. Assessment of Business Information Access Problems in Uganda

    Directory of Open Access Journals (Sweden)

    Constant Okello-Obura

    2007-09-01

    Full Text Available Effective utilization of quality business information is crucial in attaining long-term and sustainable economic growth of the Small and Medium Enterprises (SMEs. It is established that SMEs in northern Uganda operate in a business environment that is characterized by fragmented and incomplete information. It is a situation where an awareness of markets, technology, policies, regulations and finance is limited because businesses fail to receive timely business information. This article reports a portion of the results of a larger study using a descriptive design with survey research and other techniques. The study examined the problems SMEs in northern Uganda face in accessing business information; identified problems information providers face in providing business information to the SMEs in the region and attempted to establish whether SMEs in northern Uganda use public libraries in accessing business information as should be expected. The study’s respondents included the SMEs, information providers and business policy makers with the response rate of 87.3%; 72% and 85% respectively. The article proposes strategic interventions for business information to be accessed by the SMEs. It concludes that there is a need for Uganda and, in particular, northern Uganda to develop a strategy for business information access by the SMEs

  11. How small business health exchanges can offer value to their future customers--and why they must.

    Science.gov (United States)

    Kingsdale, Jon

    2012-02-01

    The success of the Small Business Health Options Program (SHOP)-health insurance exchanges targeted at the small-group market and opening for business in January 2014-will depend in large part on persuading small employers and qualified health plans to participate. The most important objective will be offering employers lower-cost health plans than they have now. Other critical objectives will be offering small firms administrative efficiencies and access to choices among high-value plans that are not offered elsewhere. This article frames the challenges that exchanges will encounter in meeting these objectives. In particular, it discusses the advisability of small-business exchanges' offering an "employee choice" model (which the article describes in detail); of combining the small-business and individual exchanges to broaden product offerings and gain operational efficiencies; and of encouraging low-cost plans to enter the exchange market, perhaps by enabling Medicaid managed care plans to offer comparable commercial products, and in turn affording health plans access to a uniquely motivated market of small firms and their workers who want affordable coverage.

  12. InfoQUEST: An Online Catalog for Small Libraries.

    Science.gov (United States)

    Campbell, Bonnie

    1984-01-01

    InfoQUEST is a microcomputer-based online public access catalog, designed for the small library handling file sizes up to 25,000 records. Based on the IBM-PC, or compatible machines, the system will accept downloading, in batch mode, of records from the library's file on the UTLAS Catalog Support System. (Author/EJS)

  13. A New Regime of SME Finance in Emerging Asia: Enhancing Access to Growth Capital and Policy Implications

    OpenAIRE

    Shigehiro Shinozaki

    2014-01-01

    While finance is critical for small and medium-sized enterprises (SMEs) to survive and grow, most SMEs suffer from poor access to finance. Given the pronounced global financial uncertainty, stable access to appropriate funding sources has become even more difficult for SMEs to attain. Lessons from the global financial crisis have motivated many countries to consider SME access to finance beyond conventional bank credit and to diversify their domestic financial systems. This paper uses empiric...

  14. Assessing the Doha Round: Market Access, Transactions Costs and Aid for Trade Facilitation

    OpenAIRE

    Hoekman, Bernard; Nicita, Alessandro

    2010-01-01

    This paper compares the predicted trade impacts of a successful Doha Round with the trade effects of actions aimed at reducing domestic trade costs for traders in developing countries and the world as a whole. We show that a relatively small reduction in trade costs will generate trade impacts that are larger than what is likely to emerge even from a relatively ambitious Doha Round market access outcome. This illustrates the importance of complementing market access commitments with measures ...

  15. 77 FR 9882 - Arsenic Small Systems Compliance and Alternative Affordability Criteria Working Group; public...

    Science.gov (United States)

    2012-02-21

    ... affordability criteria that give extra weight to small, rural, and lower income communities. This meeting will... held via the Internet using a Webcast and teleconference. Registrants will receive an Internet access... affordability criteria that give extra weight to small, rural, and lower income communities. Based upon input...

  16. Selecting An Open Access Journal for Publication: Be Cautious

    Science.gov (United States)

    Hoffecker, Lilian; Hastings-Tolsma, Marie; Vincent, Deborah; Zuniga, Heidi

    2015-12-04

    Nurse scholars and clinicians seek to publish their research and scholarly findings to strengthen both nursing science and clinical practice. Traditionally subscription-based publications have been the mainstay of knowledge dissemination. However, subscription costs have tended to restrict access to many journals to a small, specialized, academic community, a limitation that has contributed to the development of open access (OA) publications. OA journals have a powerful appeal as they allow greater access to scholars and consumers on a global level. However, many OA journals depend on an author-pays model that may lead to unintended and undesirable consequences for authors. Today, it is easier than ever to share scholarly findings, but authors need to be vigilant when selecting a journal in which to publish. In this article, we discuss the background of open access journals and describe key consideration to distinguish between reputable publications and those that may lead authors astray. We conclude that despite controversy and concerns related to publishing in OA journals, these journals do provide opportunities for researchers and clinicians to raise the profile of their work and ensure a robust, scholarly communication system.

  17. Distributed Access View Integrated Database (DAVID) system

    Science.gov (United States)

    Jacobs, Barry E.

    1991-01-01

    The Distributed Access View Integrated Database (DAVID) System, which was adopted by the Astrophysics Division for their Astrophysics Data System, is a solution to the system heterogeneity problem. The heterogeneous components of the Astrophysics problem is outlined. The Library and Library Consortium levels of the DAVID approach are described. The 'books' and 'kits' level is discussed. The Universal Object Typer Management System level is described. The relation of the DAVID project with the Small Business Innovative Research (SBIR) program is explained.

  18. Radiotherapy in small countries.

    Science.gov (United States)

    Barton, Michael B; Zubizarreta, Eduardo H; Polo Rubio, J Alfredo

    2017-10-01

    To examine the availability of radiotherapy in small countries. A small country was defined as a country with a population less than one million persons. The economic status of each country was defined using the World Bank Classification. The number of cancers in each country was obtained from GLOBOCAN 2012. The number of cancer cases with an indication or radiotherapy was calculated using the CCORE model. There were 41 countries with a population of under 1 million; 15 were classified as High Income, 15 Upper Middle Income, 10 Lower Middle Income and one Low Income. 28 countries were islands. Populations ranged from 799 (Holy See) to 886450 (Fiji) and the total number of cancer cases occurring in small countries was 21,043 (range by country from 4 to 2476). Overall the total number of radiotherapy cases in small countries was 10982 (range by country from 2 to 1239). Radiotherapy was available in all HIC islands with 80 or more new cases of cancer in 2012 but was not available in any LMIC island. Fiji was the only LMIC island with a large radiotherapy caseload. Similar caseloads in non-island LMIC all had radiotherapy services. Most non-island HIC did not have radiotherapy services presumably because of the easy access to radiotherapy in neighbouring countries. There are no radiotherapy services in any LMIC islands. Copyright © 2017. Published by Elsevier Ltd.

  19. Design & Evaluation of an Accessible Hybrid Violin Platform

    DEFF Research Database (Denmark)

    Overholt, Daniel; Gelineck, Steven

    2014-01-01

    We introduce and describe the initial evaluation of a new accessible (easily replicable) augmented violin prototype. Our research is focused on the user experience when playing such hybrid physical- digital instruments, and exploration of novel interactive performance techniques. The goal of wider...... platform accessibility for players and other researchers is approached via a simple ‘do-it-yourself’ design described herein. All hardware and software elements are open- source, and the build process requires minimal electronics skills. Cost has also been kept to a minimum where possible. Our initial...... that incorporates orientation/gesture sensors as well, with the resulting sound amplified and rendered via small speakers mounted directly to the instrument. The platform combines all necessary elements for digitally-mediated interactive performance; the need for a traditional computer only arises when developing...

  20. MODERATING EFFECT OF ENTREPRENEURIAL NETWORKING ON THE RELATIONSHIP BETWEEN ACCESS TO FINANCE AND PERFORMANCE OF MICRO AND SMALL ENTERPRISES

    Directory of Open Access Journals (Sweden)

    MUZAFFAR ASAD

    2016-04-01

    Full Text Available The study aim to find the impact of access to finance for improving the performance of MSEs in Punjab, Pakistan. The researchers also try to further estimate the moderating effect of entrepreneurial networking on the relationship between access to finance and performance of MSEs in Punjab, Pakistan. Survey research was employed to collect the data. The data for the study was collected with the help of a questionnaire adapted from the past studies. The reliability of the instrument that was used to collect data was ensured through Cronbach’s alpha and composite reliability. After ensuring the reliability of instrument, structural equation modeling was conducted by using PLS-3. The results of the study supported the arguments raised in the study that there is a positive relationship between access to finance and performance of MSEs in Punjab, Pakistan. The results also supported the argument of moderating effect of entrepreneurial networking on the relationship between access to finance and performance of MSEs in Punjab, Pakistan. The explained variation calculated through R2 has also shown that the overall model is explaining 47.1 % variation in the performance of MSEs in Punjab, Pakistan.

  1. Screening wild oat accessions from Morocco for resistance to Puccinia coronata

    Science.gov (United States)

    Here we report the screening of 338 new accessions of 11 different wild oat species (Avena) from the USDA Small Grains Collection for resistance to crown rust (Puccinia coronata). Wild oat species were originally collected in Morocco by C. Al Faiz, INRAT Rabat: Avena agadiriana, A. atlantica, A. bar...

  2. Remotely Operated Vehicle (ROV) System for Horizontal Tanks. Innovative Technology Summary Report

    International Nuclear Information System (INIS)

    2001-01-01

    The U.S. Department of Energy (DOE) is responsible for cleaning and closing over 300 small and large underground tanks across the DOE complex that are used for storing over 1-million gal of high- and low-level radioactive and mixed waste (HLW, LLW, and MLLW). The contents of these aging tanks must be sampled to analyze for contaminants to determine final disposition of the tank and its contents. Access to these tanks is limited to small-diameter risers that allow for sample collection at only one discrete point below this opening. To collect a more representative sample without exposing workers to tank interiors, a remote-controlled retrieval method must be used. Many of the storage tanks have access penetrations that are 18 in. in diameter and, therefore, are not suitable for deployment of large vehicle systems like the Houdini (DOE/EM-0363). Often, the tanks offer minimal headspace and are so cluttered with pipes and other vertical obstructions that deployment of long-reach manipulators becomes an impractical option. A smaller vehicle system is needed that can deploy waste retrieval, sampling, and inspection tools into these tanks. The Oak Ridge National Laboratory (ORNL), along with ROV Technologies, Inc., and The Providence Group, Inc., (Providence) has developed the Scarab III remotely operated vehicle system to meet this need. The system also includes a containment and deployment structure and a jet pump-based, waste-dislodging and conveyance system to use in these limited-access tanks. The Scarab III robot addresses the need for a vehicle-based, rugged, remote-controlled system for collection of representative samples of tank contents. This document contains information on the above-mentioned technology, including description, applicability, cost, and performance data

  3. Web accessibility standards and disability: developing critical perspectives on accessibility.

    Science.gov (United States)

    Lewthwaite, Sarah

    2014-01-01

    Currently, dominant web accessibility standards do not respect disability as a complex and culturally contingent interaction; recognizing that disability is a variable, contrary and political power relation, rather than a biological limit. Against this background there is clear scope to broaden the ways in which accessibility standards are understood, developed and applied. Commentary. The values that shape and are shaped by legislation promote universal, statistical and automated approaches to web accessibility. This results in web accessibility standards conveying powerful norms fixing the relationship between technology and disability, irrespective of geographical, social, technological or cultural diversity. Web accessibility standards are designed to enact universal principles; however, they express partial and biopolitical understandings of the relation between disability and technology. These values can be limiting, and potentially counter-productive, for example, for the majority of disabled people in the "Global South" where different contexts constitute different disabilities and different experiences of web access. To create more robust, accessible outcomes for disabled people, research and standards practice should diversify to embrace more interactional accounts of disability in different settings. Implications for Rehabilitation Creating accessible experiences is an essential aspect of rehabilitation. Web standards promote universal accessibility as a property of an online resource or service. This undervalues the importance of the user's intentions, expertize, their context, and the complex social and cultural nature of disability. Standardized, universal approaches to web accessibility may lead to counterproductive outcomes for disabled people whose impairments and circumstances do not meet Western disability and accessibility norms. Accessible experiences for rehabilitation can be enhanced through an additional focus on holistic approaches to

  4. Thermal Performance Analysis For Small Ion-Exchange Cesium Removal Process

    International Nuclear Information System (INIS)

    Lee, S.; King, W.

    2009-01-01

    The In-Riser Ion Exchange program focuses on the development of in-tank systems to decontaminate high level waste (HLW) salt solutions at the Savannah River Site (SRS) and the Hanford Site. Small Column Ion Exchange (SCIX) treatment for cesium removal is a primary in-riser technology for decontamination prior to final waste immobilization in Saltstone. Through this process, radioactive cesium from the salt solution is adsorbed onto the ion exchange media which is packed within a flow-through column. Spherical Resorcinol-Formaldehyde (RF) is being considered as the ion exchange media for the application of this technology at both sites. A packed column loaded with media containing radioactive cesium generates significant heat from radiolytic decay. Under normal operating conditions, process fluid flow through the column can provide adequate heat removal from the columns. However, in the unexpected event of loss of fluid flow or fluid drainage from the column, the design must be adequate to handle the thermal load to avoid unacceptable temperature excursions. Otherwise, hot spots may develop locally which could degrade the performance of the ion-exchange media or the temperature could rise above column safety limits. Data exists which indicates that performance degradation with regard to cesium removal occurs with RF at 65C. In addition, the waste supernate solution will boil around 130C. As a result, two temperature limits have been assumed for this analysis. An additional upset scenario was considered involving the loss of the supernate solution due to inadvertent fluid drainage through the column boundary. In this case, the column containing the loaded media could be completely dry. This event is expected to result in high temperatures that could damage the column or cause the RF sorbent material to undergo undesired physical changes. One objective of these calculations is to determine the range of temperatures that should be evaluated during testing with the RF

  5. Comparison of Radial Access, Guided Femoral Access, and Non-Guided Femoral Access Among Women Undergoing Percutaneous Coronary Intervention.

    Science.gov (United States)

    Koshy, Linda M; Aberle, Laura H; Krucoff, Mitchell W; Hess, Connie N; Mazzaferri, Ernest; Jolly, Sanjit S; Jacobs, Alice; Gibson, C Michael; Mehran, Roxana; Gilchrist, Ian C; Rao, Sunil V

    2018-01-01

    This study was conducted to determine the association between radial access, guided femoral access, and non-guided femoral access on postprocedural bleeding and vascular complications after percutaneous coronary intervention (PCI). Bleeding events and major vascular complications after PCI are associated with increased morbidity, mortality, and cost. While the radial approach has been shown to be superior to the femoral approach in reducing bleeding and vascular complications, whether the use of micropuncture, fluoroscopy, or ultrasound mitigates these differences is unknown. We conducted a post hoc analysis of women in the SAFE-PCI for Women trial who underwent PCI and had the access method identified (n = 643). The primary endpoint of postprocedure bleeding or vascular complications occurring within 72 hours or at discharge was adjudicated by an independent clinical events committee and was compared based on three categories of access technique: radial, guided femoral (fluoroscopy, micropuncture, ultrasound), or non-guided femoral (none of the aforementioned). Differences between the groups were determined using multivariate logistic regression using radial access as the reference. Of the PCI population, 330 underwent radial access, 228 underwent guided femoral access, and 85 underwent non-guided femoral access. There was a statistically significant lower incidence of the primary endpoint with radial access vs non-guided femoral access; however, there was no significant difference between radial approach and femoral access guided by fluoroscopy, micropuncture, or ultrasound. This post hoc analysis demonstrates that while radial access is safer than non-guided femoral access, guided femoral access appears to be associated with similar bleeding events or vascular complications as radial access.

  6. The Impact of Micro-Finance on the Performance of Small-Scale ...

    African Journals Online (AJOL)

    The Impact of Micro-Finance on the Performance of Small-Scale Enterprises: A Comparison of ... PROMOTING ACCESS TO AFRICAN RESEARCH ... the impact that the study-MFIs are making on their SMEs-client in the Wa Municipality.

  7. 77 FR 74908 - Small Business Investment Companies-Early Stage SBICs

    Science.gov (United States)

    2012-12-18

    ... Early Stage SBICs, SBA seeks to expand entrepreneurs' access to capital and encourage innovation as part... addressing barriers to success for entrepreneurs and small businesses. II. Management Assessment... return expectations of a fund and excessive concentration in a single year could substantially increase...

  8. 77 FR 25775 - Small Business Investment Companies-Early Stage SBICs

    Science.gov (United States)

    2012-05-01

    ... expand entrepreneurs' access to capital and encourage innovation as part of President Obama's Start-Up... research, and addressing barriers to success for entrepreneurs and small businesses. II. Management... single year could substantially increase program risk. Therefore, SBA reserves the right, when licensing...

  9. Broadband Access

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Broadband Access. Worldwide market for broadband access $30 Billion! Over 200 million broadband subscribers worldwide! Various Competing Broadband access. Digital Subscriber line; Wireless; Optical Fiber.

  10. Sociospatial distribution of access to facilities for moderate and vigorous intensity physical activity in Scotland by different modes of transport

    Directory of Open Access Journals (Sweden)

    Lamb Karen E

    2012-07-01

    Full Text Available Abstract Background People living in neighbourhoods of lower socioeconomic status have been shown to have higher rates of obesity and a lower likelihood of meeting physical activity recommendations than their more affluent counterparts. This study examines the sociospatial distribution of access to facilities for moderate or vigorous intensity physical activity in Scotland and whether such access differs by the mode of transport available and by Urban Rural Classification. Methods A database of all fixed physical activity facilities was obtained from the national agency for sport in Scotland. Facilities were categorised into light, moderate and vigorous intensity activity groupings before being mapped. Transport networks were created to assess the number of each type of facility accessible from the population weighted centroid of each small area in Scotland on foot, by bicycle, by car and by bus. Multilevel modelling was used to investigate the distribution of the number of accessible facilities by small area deprivation within urban, small town and rural areas separately, adjusting for population size and local authority. Results Prior to adjustment for Urban Rural Classification and local authority, the median number of accessible facilities for moderate or vigorous intensity activity increased with increasing deprivation from the most affluent or second most affluent quintile to the most deprived for all modes of transport. However, after adjustment, the modelling results suggest that those in more affluent areas have significantly higher access to moderate and vigorous intensity facilities by car than those living in more deprived areas. Conclusions The sociospatial distributions of access to facilities for both moderate intensity and vigorous intensity physical activity were similar. However, the results suggest that those living in the most affluent neighbourhoods have poorer access to facilities of either type that can be reached on foot

  11. Identifying and intervening on barriers to healthcare access among members of a small Korean community in the southern USA.

    Science.gov (United States)

    Rhodes, Scott D; Song, Eunyoung; Nam, Sang; Choi, Sarah J; Choi, Seungyong

    2015-04-01

    We used community-based participatory research (CBPR) to explore barriers to healthcare access and utilization and identify potentially effective intervention strategies to increase access among members of the Korean community in North Carolina (NC). Our CBPR partnership conducted 8 focus groups with 63 adult Korean immigrants in northwest NC and 15 individual in-depth interviews and conducted an empowerment-based community forum. We identified 20 themes that we organized into four domains, including practical barriers to health care, negative perceptions about care, contingencies for care, and provider misconceptions about local needs. Forum attendees identified four strategies to improve Korean community health. Despite the implementation of the Patient Protection and Affordable Care Act (ACA), many Korean community members will continue to remain uninsured, and among those who obtain insurance, many barriers will remain. It is imperative to ensure the health of this highly neglected and vulnerable community. Potential strategies include the development of (1) low-literacy materials to educate members of the Korean community about how to access healthcare services, (2) lay health advisor programs to support navigation of service access and utilization, (3) church-based programming, and (4) provider education to reduce misconceptions about Korean community needs. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Oskarshamn 1 RPV: cleaning it out before venturing in

    International Nuclear Information System (INIS)

    Svantesson, I.; Ingemansson, K.-E.; Ericsson, J.-O.; Bjerler, J.

    1994-01-01

    An opportunity to carry out nondestructive testing of the bottom dome of the Oskarshamn 1 BWR vessel arose when all the reactor internals had to be removed to replace cracked feedwater risers. This necessitated decontamination of the lower part of the vessel, the four main recirculation loops, the residual heat removal system and the reactor water clean-up system. A decontamination factor of between 100 and 1000 was achieved, making the vessel accessible for manual inspection and repair work. The decontamination process, using the Siemens KWU CORD method, is outlined. (UK)

  13. Transportation Accessibility and Location Choice of Japanese-Funded Electronic Information Manufacturing Firms in Shanghai

    Directory of Open Access Journals (Sweden)

    Haining Jiang

    2018-02-01

    Full Text Available With the rapid development of globalization, information communication and transportation, it is argued that the effect of transportation accessibility in the location choice of manufacturing firms has diminished. However, comprehensive and systematic research on the impact of transportation accessibility on firm location choice in cities remains scarce. Taking Shanghai as the research area, this paper uses a catalog of Japanese-funded electronic information manufacturing firms to explore the influence of transportation accessibility on their location choice. The paper first describes firm distribution using the nuclear density estimation method. The Poisson regression model is then used to estimate the significance of transportation accessibility in influencing firm location. The empirical results show that most of the firms are concentrated in the inner suburbs of Shanghai, with only a small number in the outer suburban areas. The spatial coupling relationship between firm distribution and transportation accessibility is significant. These firms tend to choose areas with good accessibility to transportation infrastructure, and, in particular, the effect of airport accessibility is significant. Compared with the joint venture enterprises, wholly-owned Japanese enterprises are more inclined to be in areas with better transportation accessibility.

  14. Two-port access versus four-port access laparoscopic ovarian cystectomy.

    Science.gov (United States)

    Choi, Won-Kyu; Kim, Jang-Kew; Yang, Jung-Bo; Ko, Young-Bok; Nam, Sang-Lyun; Lee, Ki-Hwan

    2014-09-01

    This study was conducted to compare the surgical outcomes between two-port access and four-port access laparoscopic ovarian cystectomy. Four hundred and eighty nine patients who had received two-port access laparoscopic ovarian cystectomy (n=175) and four-port access laparoscopic ovarian cystectomy (n=314) in Chungnam National University Hospital from January 2009 to August 2012 were analyzed retrospectively. The data were compared between the bilaterality of the cysts and cyst diameter of less than 6 cm and 6 cm or more. There were no significant differences in patient's age, parity, body weight, body mass index and history of previous surgery between the two-port and four-port access laparoscopy group. Bilaterality of ovarian cysts was more in fourport access laparoscopy group (13.7% vs. 32.5%, P=0.000). There were no significant differences in operation time, hemoglobin change, hospital stay, adhesiolysis, transfusion, and insertion of hemo-vac between the two-port and four-port access laparoscopy group for size matched compare. However additional analgesics were more in four-port access laparoscopy group for unilateral ovarian cystectomy. Two-port access laparoscopic surgery was feasible and safe for unilateral and bilateral ovarian cystectomy compare with four-port access laparoscopic surgery.

  15. Test procedure for calibration, grooming and alignment of the LDUA Optical Alignment Scope

    International Nuclear Information System (INIS)

    Potter, J.D.

    1995-01-01

    The Light Duty Utility Arm (LDUA) is a remotely operated manipulator used to enter into underground waste tanks through one of the tank risers. The LDUA must be carefully aligned with the tank riser during the installation process. The Optical Alignment Scope (OAS) is used to determine when optimum alignment has been achieved between the LDUA and the riser. This procedure is used to assure that the instrumentation and equipment comprising the OAS is properly adjusted in order to achieve its intended functions successfully

  16. HACCP in Small Companies:Benefit or Burden?

    Institute of Scientific and Technical Information of China (English)

    EuniceTaylor

    2001-01-01

    This paper acknowledges the importance of small companies across the food chain and indntifies the slow uptake of HACCP in these companies as an area of concern for the production of safe food,This set the scene for an analysis of the barriers to HACCP implementation which include availability of appropriate training in HACCP methodology,access to technical expertise and the general resource problems of time and money ,The burden that this places on the small business,particularly in terms of documentation,validation and verification,are then discussed,The paper concludes with a summary of the burdens and benefits that this sector faces as it moves towards compliance with food safety legislation.

  17. Experimental Evaluation of Interference Rejection Combining for 5G small cells,

    DEFF Research Database (Denmark)

    Assefa, Dereje; Berardinelli, Gilberto; Tavares, Fernando Menezes Leitão

    2015-01-01

    The Interference Rejection Combining (IRC) receiver can significantly boost the network throughput in scenarios characterized by dense uncoordinated deployment of small cells, as targeted by future 5th generation (5G) radio access technology. This paper presents an experimental study...

  18. Few data but many fish: marine small-scale fisheries catches for ...

    African Journals Online (AJOL)

    ... substantially under-reported national data puts authorities under serious risk of over-licensing fishing access and mismanaging marine ecosystems and national food security. Keywords: catch rates, catch reconstructions, food security, Malthusian overfishing, small-scale fisheries, sub-Saharan Africa, subsistence fisheries

  19. Agents of Change: Studies on the Policy Environment for Small ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Agents of Change presents the results of an international conference held in Africa. It provides practical solutions and suggestions for real change. It discusses national strategies for small enterprises, examines legal, regulatory, and tax reform, and makes proposals on how to improve competitiveness and access to credit.

  20. The Challenge of Access: Using Road Construction as a Tool in Counterinsurgency

    Science.gov (United States)

    2011-06-10

    furnished the advertised advantages to the tribes, and the frequency of military movement on them betrayed their fundamental use as methods of access into...staging area. Nestled in a small valley amongst towering Shahmardan Mountains, the area was referred to as the ―belly button.‖ The Chenartu valley

  1. Digital loyalty card "big data' and small business marketing: Formal versus informal or complementary?

    OpenAIRE

    Donnelly, Christina; Simmons, Geoff; Armstrong, Gillian; Fearne, Andrew

    2015-01-01

    This article proposes that a complementary relationship exists between the formalised nature of digital loyalty card data, and the informal nature of small business market orientation. A longitudinal, case-based research approach analysed this relationship in small firms given access to Tesco Clubcard data. The findings reveal a new-found structure and precision in small firm marketing planning from data exposure; this complemented rather than conflicted with an intuitive feel for markets. In...

  2. Firms Started As Franchises Have Lower Survival Rates Than Independent Small Business Startups

    OpenAIRE

    Timothy Bates

    1994-01-01

    Aspiring entrepreneurs choosing to become franchisees certainly expect to improve their chances of survival during the turbulent early years of business startup and operation. Alignment with a franchiser parent company offers the franchisee managerial assistance, access to financial capital, and access to markets via the right to utilize the parent company trademark. This study examines survival patterns among franchise and nonfranchise small firms started between 1984 and 1987: survival thro...

  3. CFD simulation of CO_2 sorption on K_2CO_3 solid sorbent in novel high flux circulating-turbulent fluidized bed riser: Parametric statistical experimental design study

    International Nuclear Information System (INIS)

    Thummakul, Theeranan; Gidaspow, Dimitri; Piumsomboon, Pornpote; Chalermsinsuwan, Benjapon

    2017-01-01

    Highlights: • Circulating-turbulent fluidization was proved to be advantage on CO_2 sorption. • The novel regime was proven to capture CO_2 higher than the conventional regimes. • Uniform solid particle distribution was observed in the novel fluidization regime. • The system continuity had more effect in the system than the process system mixing. • Parametric experimental design analysis was studied to evaluate significant factor. - Abstract: In this study a high flux circulating-turbulent fluidized bed (CTFB) riser was confirmed to be advantageous for carbon dioxide (CO_2) sorption on a potassium carbonate solid sorbent. The effect of various parameters on the CO_2 removal level was evaluated using a statistical experimental design. The most appropriate fluidization regime was found to occur between the turbulent and fast fluidization regimes, which was shown to capture CO_2 more efficiently than conventional fluidization regimes. The highest CO_2 sorption level was 93.4% under optimized CTFB operating conditions. The important parameters for CO_2 capture were the inlet gas velocity and the interactions between the CO_2 concentration and the inlet gas velocity and water vapor concentration. The CTFB regime had a high and uniform solid particle distribution in both the axial and radial system directions and could transport the solid sorbent to the regeneration reactor. In addition, the process system continuity had a stronger effect on the CO_2 removal level in the system than the process system mixing.

  4. Open access

    NARCIS (Netherlands)

    Valkenburg, P.M.

    2015-01-01

    Open access week Van 19 tot en met 25 oktober 2015 vond wereldwijd de Open Access Week plaats. Tijdens deze week werden er over de hele wereld evenementen georganiseerd waar open access een rol speelt. Ook in Nederland zijn er diverse symposia, workshops en debatten georganiseerd zoals het debat in

  5. Open Access @ DTU

    DEFF Research Database (Denmark)

    Ekstrøm, Jeannette

    Open Access is high on the agenda in Denmark and internationally. Denmark has announced a national strategy for Open Access that aims to achieve Open Access to 80% in 2017 and 100% in 2022 to peer review research articles. All public Danish funders as well as H2020 requires that all peer review...... articles that is an outcome of their funding will be Open Access. Uploading your full texts (your final author manuscript after review ) to DTU Orbit is a fundamental part of providing Open Access to your research. We are here to answer all your questions with regards to Open Access and related topics...... such as copyright, DTU Orbit, Open Access journals, APCs, Vouchers etc....

  6. Self generation, small generation, and embedded generation issues

    International Nuclear Information System (INIS)

    2001-01-01

    The New Brunswick Market Design Committee for electric power restructuring has been directed to examine issues regarding cogeneration and small-scale, on-site generation and how they will fit within the framework of the bilateral contract market. The Committee will also have to deal with issues of generation embedded in a distribution system. The Committee has defined cogeneration as the simultaneous production of electricity and useful thermal energy. Self-generation has been defined as small-scale power generation by an end-user, while embedded generation has been defined as a generation facility that is located within a distribution utility but is not directly connected to the transmission system. The Committee has postponed its decision on whether embedded generation will be eligible to participate under the bilateral contract market for electricity. This report discusses general issues such as the physical support of generation, market support of generation, transition issues and policy issues. It also discusses generation support issues such as operating reserves, transmission tariff issues, and distribution tariffs. Market support issues such as transmission access for generation sales were also considered, along with market access for generation sales, and net metering for behind the meter generation. 7 refs., 1 tab

  7. SMES' SECTOR ACCESS TO FINANCE: AN OVERVIEW

    Directory of Open Access Journals (Sweden)

    Roman Angela

    2011-07-01

    Full Text Available Through their contribution to the creation of added value and new jobs, the small and medium enterprises (SMEs have a significant role in the economic and social development of a country. However, these enterprises are facing numerous obstacles that limit their performance, growth and development. Among the difficulties faced by SMEs, the access to finance is often reported as a major obstacle to the deployment and expansion of their activity. The access to finance is crucial for efficient allocation of financial resources and entrepreneurial development, which explains the major interest given to this subject both by the academic literature and the policy makers. The paper aims to highlight the difficulties faced by SMEs in securing financing resources, emphasizing the differences between countries and also between SMEs and large enterprises. Knowing the difficulties in SMEs financing is essential for policy makers in order to design and implement appropriate measures, which will help to improve the access to financing for these enterprises. Thus, another issue addressed, synthetically, in this paper aims the measures taken by public authorities in order to support the access to financing for SMEs. The research methodology used in this paper starts with a literature review in order to highlight the importance of the subject addressed in our research. The analysis conducted in this paper is based on data and statistics provided mainly by the World Bank surveys, by certain empirical studies and by the National Council of Small and Medium Sized Private Enterprises in Romania. Based on the methodology used, the paper indicates the difficulties in SMEs financing and the crucial importance of enhancing the public authorities concerns regarding their alleviation, especially by adopting measures focused on increasing financial development, which would ensure greater availability of financing for businesses and thus economic growth. The limited

  8. Neighborhood crime and access to health-enabling resources in Chicago

    Directory of Open Access Journals (Sweden)

    Elizabeth L. Tung

    2018-03-01

    Full Text Available Neighborhood crime may be an important social determinant of health in many high-poverty, urban communities, yet little is known about its relationship with access to health-enabling resources. We recruited an address-based probability sample of 267 participants (ages ≥35 years on Chicago's South Side between 2012 and 2013. Participants were queried about their perceptions of neighborhood safety and prior experiences of neighborhood crime. Survey data were paired to a comprehensive, directly-observed census of the built environment on the South Side of Chicago. Multivariable logistic regression models were used to examine access to health-enabling resources (potential and realized access as a function of neighborhood crime (self-reported neighborhood safety and prior experience of theft or property crime, adjusting for sociodemographic characteristics and self-reported health status. Low potential access was defined as a resident having nearest resources >1 mile from home; poor realized access was defined as bypassing nearby potential resources to use resources >1 mile from home. Poor neighborhood safety was associated with low potential access to large grocery stores (AOR = 1.73, 95% CI = 1.04, 2.87, pharmacies (AOR = 2.24, 95% CI = 1.33, 3.77, and fitness resources (AOR = 1.93, 95% CI = 1.15, 3.24, but not small grocery stores. Any prior experience of neighborhood crime was associated with higher adjusted odds of bypassing nearby pharmacies (AOR = 3.78, 95% CI = 1.11, 12.87. Neighborhood crime may be associated with important barriers to accessing health-enabling resources in urban communities with high rates of crime. Keywords: Built environment, Neighborhood crime, Access to resources, Social determinants of health, Obesity, Hypertension

  9. New ways to access the transverse spin content of the nucleon

    International Nuclear Information System (INIS)

    Beiyad, M El; Pire, B; Szymanowski, L; Wallon, S

    2011-01-01

    We first describe a new way to access the chiral odd transversity parton distribution in the proton through the photoproduction of lepton pairs. The basic ingredient is the interference of the usual Bethe-Heitler or Drell-Yan amplitudes with the amplitude of a process, where the photon couples to quarks through its chiral-odd distribution amplitude, which is normalized to the magnetic susceptibility of the QCD vacuum. We also show how the chiral-odd transversity generalized parton distributions (GPDs) of the nucleon can be accessed experimentally through the exclusive electro - or photoproduction process of a meson pair with a large invariant mass and when the final nucleon has a small transverse momentum. We calculate perturbatively the scattering amplitude at leading order, both in the high energy domain which may be accessed in electron-ion colliders and in the medium energy range. Estimated rates are encouraging.

  10. The Governance of Fair Trade System: Evidence from Small Honey Producers in Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Luciana Marques Vieira

    2009-10-01

    Full Text Available This paper discusses Fair Trade [FT] certification as a way to include small producers in global value chains, and identifies the main barriers for small honey producers from RS to meet these criteria. A new trading system such as FT has been providing access for food products coming from small farmers from developing countries. The method of this study integrates global value chain analysis and the methodology proposed by Paul (2005 to analyse FT as development projects. This study is three-fold: first to characterise the FT system; then to present the role of governance by third party certifiers such as FLO-CERT and finally to provide empirical evidence of the main difficulties that small producers have to comply with FT, such as export and organisation capacity. Our findings show that large retailers recently became big players in the FT system. The certification costs are high but can provide market access though there is a risk of overspecialisation.

  11. ICT Adoption in Micro and Small Firms: Can Internet Access Improve Labour Productivity?

    OpenAIRE

    Viollaz, Mariana

    2018-01-01

    The rapid spread of information and communication technologies may increase firms’ productivity with important consequences for job creation and for economic growth. This article contributes to this discussion by analysing the impact of internet adoption on labour productivity and the mechanisms shaping this relationship in Peruvian micro and small manufacturing firms over the period 2011-2013. The article estimates a reduced form where labour productivity is a function of internet adoptio...

  12. One-fifth of nonelderly Californians do not have access to job-based health insurance coverage.

    Science.gov (United States)

    Lavarreda, Shana Alex; Cabezas, Livier

    2010-11-01

    Lack of job-based health insurance does not affect just workers, but entire families who depend on job-based coverage for their health care. This policy brief shows that in 2007 one-fifth of all Californians ages 0-64 who lived in households where at least one family member was employed did not have access to job-based coverage. Among adults with no access to job-based coverage through their own or a spouse's job, nearly two-thirds remained uninsured. In contrast, the majority of children with no access to health insurance through a parent obtained public health insurance, highlighting the importance of such programs. Low-income, Latino and small business employees were more likely to have no access to job-based insurance. Provisions enacted under national health care reform (the Patient Protection and Affordable Care Act of 2010) will aid some of these populations in accessing health insurance coverage.

  13. Small businesses and the Affordable Care Act of 2010.

    Science.gov (United States)

    Collins, Sara R; Davis, Karen; Nicholson, Jennifer L; Stremikis, Kristof

    2010-09-01

    The Patient Protection and Affordable Care Act (ACA) includes several short- and long-term provisions designed to help small businesses pay for and maintain health insurance for their workers, and to allow workers without employer coverage to gain access to affordable, comprehensive health insurance. Provisions include a small business tax credit to offset premium costs for firms that offer coverage starting this taxable year, establishment of state-based insurance exchanges that promise to lower administrative costs and pool risk more broadly, and creation of new market rules and an essential benefit standard to protect small firms and their workers. Analysis shows that up to 16.6 million workers are in firms that would be eligible for the tax credit in 2010 to 2013. Over the next 10 years, small businesses and organizations could receive an estimated $40 billion in federal support through the premium credit program.

  14. 77 FR 51068 - Remedies for Small Copyright Claims: Additional Comments

    Science.gov (United States)

    2012-08-23

    ... Adobe Portable Document File (PDF) format that contains searchable, accessible text (not an image..., 2012 from 9:30 a.m. to 3:30 p.m. The agendas and the process for submitting requests to participate in... discussion covered topics ranging from constitutional considerations to the definition of a ``small claim...

  15. On the Impact of Closed Access and Users Identities in Spectrum-Shared Overlaid Wireless Networks

    KAUST Repository

    Radaydeh, Redha M.; Gaaloul, Fakhreddine; Alouini, Mohamed-Slim

    2016-01-01

    © 2015 IEEE. This paper develops analytical models to investigate the impact of various operation terms and parameters on the downlink performance of spectrum-shared overlaid networks under closed-access small cells deployment. It is considered

  16. Access Denied! Contrasting Data Access in the United States and Ireland

    Directory of Open Access Journals (Sweden)

    Grogan Samuel

    2016-07-01

    Full Text Available The ability of an Internet user to access data collected about himself as a result of his online activity is a key privacy safeguard. Online, data access has been overshadowed by other protections such as notice and choice. This paper describes attitudes about data access. 873 US and Irish Internet users participated in a survey designed to examine views on data access to information held by online companies and data brokers. We observed low levels of awareness of access mechanisms along with a high desire for access in both participant groups. We tested three proposed access systems in keeping with industry programs and regulatory proposals. User response was positive. We conclude that access remains an important privacy protection that is inadequately manifested in practice. Our study provides insight for lawmakers and policymakers, as well as computer scientists who implement these systems.

  17. Refining fault slip rates using multiple displaced terrace risers—An example from the Honey Lake fault, NE California, USA

    Science.gov (United States)

    Gold, Ryan D.; Briggs, Richard; Crone, Anthony J.; Duross, Christopher

    2017-01-01

    Faulted terrace risers are semi-planar features commonly used to constrain Quaternary slip rates along strike-slip faults. These landforms are difficult to date directly and therefore their ages are commonly bracketed by age estimates of the adjacent upper and lower terrace surfaces. However, substantial differences in the ages of the upper and lower terrace surfaces (a factor of 2.4 difference observed globally) produce large uncertainties in the slip-rate estimate. In this investigation, we explore how the full range of displacements and bounding ages from multiple faulted terrace risers can be combined to yield a more accurate fault slip rate. We use 0.25-m cell size digital terrain models derived from airborne lidar data to analyze three sites where terrace risers are offset right-laterally by the Honey Lake fault in NE California, USA. We use ages for locally extensive subhorizontal surfaces to bracket the time of riser formation: an upper surface is the bed of abandoned Lake Lahontan having an age of 15.8 ± 0.6 ka and a lower surface is a fluvial terrace abandoned at 4.7 ± 0.1 ka. We estimate lateral offsets of the risers ranging between 6.6 and 28.3 m (median values), a greater than fourfold difference in values. The amount of offset corresponds to the riser's position relative to modern stream meanders: the smallest offset is in a meander cutbank position, whereas the larger offsets are in straight channel or meander point-bar positions. Taken in isolation, the individual terrace-riser offsets yield slip rates ranging from 0.3 to 7.1 mm/a. However, when the offset values are collectively assessed in a probabilistic framework, we find that a uniform (linear) slip rate of 1.6 mm/a (1.4–1.9 mm/a at 95% confidence) can satisfy the data, within their respective uncertainties. This investigation demonstrates that integrating observations of multiple offset elements (crest, midpoint, and base) from numerous faulted and dated terrace risers at closely spaced

  18. Authentication and Access: Accommodating Public Users in an Academic World

    Directory of Open Access Journals (Sweden)

    Lynne Weber

    2010-09-01

    Full Text Available In the fall of 2004, the Academic Computing Center, a division of the Information Technology Services Department (ITS at Minnesota State University, Mankato took over responsibility for the computers in the public areas of Memorial Library. For the first time, affiliated Memorial Library users were required to authenticate using a campus username and password, a change that effectively eliminated computer access for anyone not part of the university community. This posed a dilemma for the librarians. Because of its Federal Depository status, the library had a responsibility to provide general access to both print and online government publications for the general public. Furthermore, the library had a long tradition of providing guest access to most library resources, and there was reluctance to abandon the practice. Therefore the librarians worked with ITS to retain a small group of six computers that did not require authentication and were clearly marked for community use, along with several standup, open-access computers on each floor used primarily for searching the library catalog. The additional need to provide computer access to high school students visiting the library for research and instruction led to more discussions with ITS and resulted in a means of generating temporary usernames and passwords through a Web form. These user accommodations were implemented in the library without creating a written policy governing the use of open-access computers.

  19. An Investigation of Unified Memory Access Performance in CUDA

    Science.gov (United States)

    Landaverde, Raphael; Zhang, Tiansheng; Coskun, Ayse K.; Herbordt, Martin

    2015-01-01

    Managing memory between the CPU and GPU is a major challenge in GPU computing. A programming model, Unified Memory Access (UMA), has been recently introduced by Nvidia to simplify the complexities of memory management while claiming good overall performance. In this paper, we investigate this programming model and evaluate its performance and programming model simplifications based on our experimental results. We find that beyond on-demand data transfers to the CPU, the GPU is also able to request subsets of data it requires on demand. This feature allows UMA to outperform full data transfer methods for certain parallel applications and small data sizes. We also find, however, that for the majority of applications and memory access patterns, the performance overheads associated with UMA are significant, while the simplifications to the programming model restrict flexibility for adding future optimizations. PMID:26594668

  20. INVESTIGATING SUSPENSION OF MST SLURRIES IN A PILOT-SCALE WASTE TANK

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M.; Restivo, M.; Steeper, T.; Williams, M.; Qureshi, Z.

    2011-01-24

    The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for suspending monosodium titanate (MST), crystalline silicotitanate (CST), and simulated sludge. The purpose of this pilot scale testing is for the pumps to suspend the MST particles so that MST can be removed from the tank. The pilot-scale tank is a 1/10.85 linear scaled model of Tank 41H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 41H. The pump locations correspond to the proposed locations in Tank 41H by the SCIX program (Risers B5 and B2 for two pump configurations and Risers B5, B3, and B1 for three pump configurations).

  1. Accessibility and sensory experiences

    DEFF Research Database (Denmark)

    Ryhl, Camilla

    2010-01-01

    and accessibility. Sensory accessibility accommodates aspects of a sensory disability and describes architectural design requirements needed to ensure access to architectural experiences. In the context of architecture accessibility has become a design concept of its own. It is generally described as ensuring...... physical access to the built environment by accommodating physical disabilities. While the existing concept of accessibility ensures the physical access of everyone to a given space, sensory accessibility ensures the choice of everyone to stay and be able to participate and experience....

  2. HIGH LEVEL WASTE TANK CLOSURE PROJECT AT THE IDAHO NATIONAL ENGINEERING AND ENVIRONMENTAL LABORATORY

    International Nuclear Information System (INIS)

    Quigley, K.D.; Wessman, D.

    2003-01-01

    The Department of Energy, Idaho Operations Office (DOE-ID) is in the process of closing two underground high-level waste (HLW) storage tanks at the Idaho National Engineering and Environmental Laboratory (INEEL) to meet Resource Conservation and Recovery Act (RCRA) regulations and Department of Energy orders. Closure of these two tanks is scheduled for 2004 as the first phase in closure of the eleven 1.14 million liter (300,000 gallon) tanks currently in service at the Idaho Nuclear Technology and Engineering Center (INTEC). The INTEC Tank Farm Facility (TFF) Closure sequence consists of multiple steps to be accomplished through the existing tank riser access points. Currently, the tank risers contain steam and process waste lines associated with the steam jets, corrosion coupons, and liquid level indicators. As necessary, this equipment will be removed from the risers to allow adequate space for closure equipment and activities. The basic tank closure sequence is as follows: Empty the tank to the residual heel using the existing jets; Video and sample the heel; Replace steam jets with new jet at a lower position in the tank, and remove additional material; Flush tank, piping and secondary containment with demineralized water; Video and sample the heel; Evaluate decontamination effectiveness; Displace the residual heel with multiple placements of grout; and Grout piping, vaults and remaining tank volume. Design, development, and deployment of a remotely operated tank cleaning system were completed in June 2002. The system incorporates many commercially available components, which have been adapted for application in cleaning high-level waste tanks. The system is cost-effective since it also utilizes existing waste transfer technology (steam jets), to remove tank heel solids from the tank bottoms during the cleaning operations. Remotely operated directional spray nozzles, automatic rotating wash balls, video monitoring equipment, decontamination spray-rings, and

  3. Accession to the European Union: Advantage or Disadvantage for Czech Companies?

    Directory of Open Access Journals (Sweden)

    Dušan Litva

    2016-12-01

    Full Text Available In this paper has been studied effects of accession to the EU on Czech companies which were selected and grouped according to 5 parameters: region, legal form, operation area, business sector and size of the company defined by number of employees. Questionnaire containing 14 questions have replied in total 146 respondents. It is possible to conclude that accession to the EU brought more advantages to big global joint- stock companies than to small regional companies which were mostly negative and claimed worsening of business results due to European integration. Most of the 146 respondents asked via questionnaire containing 14 questions did not agree with acceptance of Euro, while those who agreed had been estimated 2020 as ideal year to access Eurozone. Companies in quaternary sector were mostly positive on the opposite to the companies in tertiary sector which were negative. Companies in Prague and Central Bohemia were much more positive towards EU benefits than in rest of the Czech Republic regions.

  4. Connectivity and conditional models of access and abundance of species in stream networks.

    Science.gov (United States)

    Chelgren, Nathan D; Dunham, Jason B

    2015-07-01

    Barriers to passage of aquatic organisms at stream road crossings are a major cause of habitat fragmentation in stream networks. Accordingly, large investments have been made to restore passage at these crossings, but often without estimation of population-level benefits. Here, we describe a broad-scale approach to quantifying the effectiveness of passage restoration in terms interpretable at population levels, namely numbers of fish and length of stream gained through restoration, by sampling abundance in a study design that accounts for variable biogeographic species pools, variable stream and barrier configurations, and variable probabilities of capture and detectability for multiple species. We modified an existing zero-inflated negative-binomial model to estimate the probability of site access, abundance conditional on access, and capture probability of individual fish. Therein, we modeled probability of access as a function of gradient, stream road-crossing type, and downstream access by fish simultaneously with a predictive model for abundance at sites accessible to fish. Results indicated that replacement of barriers with new crossing designs intended to allow for greater movement was associated with dramatically higher probability of access for all fishes, including migratory Pacific salmon, trout, sculpin, and lamprey. Conversely, existing non-replaced crossings negatively impacted fish distributions. Assuming no downstream constraints on access, we estimated the potential length of stream restored by the program ranged between 7.33 (lamprey) and 15.28 km (small coastal cutthroat and rainbow trout). These contributions represented a fraction of the total length available upstream (187 km) of replaced crossings. When limited ranges of species were considered, the estimated contributions of culvert replacement were reduced (1.65-km range, for longnose dace to 12.31 km for small coastal cutthroat and rainbow trout). Numbers of fish contributed ranged from

  5. Micro-lending for small farmers in Bangladesh

    OpenAIRE

    Rashid, Shahidur; Sharma, Manohar; Zeller, Manfred

    2002-01-01

    It has been long hypothesized that lack of access to credit is the main reason why, despite higher profitability of High Yielding Varieties (HYVs), farmers in developing countries continue to allocate a portion of their land to traditional crop varieties. The empirical testing of this hypothesis has generated a large body of literature with differing conclusions. This paper re-examines the issue in the context of a specially designed group-based lending program for small farmers in Bangladesh...

  6. Database implementation to fluidized cracking catalytic-FCC process

    International Nuclear Information System (INIS)

    Santana, Antonio Otavio de; Dantas, Carlos Costa; Santos, Valdemir A. dos

    2009-01-01

    A process of Fluidized Cracking Catalytic (FCC) was developed by our research group. A cold model FCC unit, in laboratory scale, was used for obtaining of the data relative to the following parameters: air flow, system pressure, riser inlet pressure, rise outlet pressure, pressure drop in the riser, motor speed of catalyst injection and density. The measured of the density is made by gamma ray transmission. For the fact of the process of FCC not to have a database until then, the present work supplied this deficiency with the implementation of a database in connection with the Matlab software. The data from the FCC unit (laboratory model) are obtained as spreadsheet of the MS-Excel software. These spreadsheets were treated before importing them as database tables. The application of the process of normalization of database and the analysis done with the MS-Access in these spreadsheets treated revealed the need of an only relation (table) for to represent the database. The Database Manager System (DBMS) chosen has been the MS-Access by to satisfy our flow of data. The next step was the creation of the database, being built the table of data, the action query, selection query and the macro for to import data from the unit FCC in study. Also an interface between the application 'Database Toolbox' (Matlab2008a) and the database was created. This was obtained through the drivers ODBC (Open Data Base Connectivity). This interface allows the manipulation of the database by the users operating in the Matlab. (author)

  7. Database implementation to fluidized cracking catalytic-FCC process

    Energy Technology Data Exchange (ETDEWEB)

    Santana, Antonio Otavio de; Dantas, Carlos Costa, E-mail: aos@ufpe.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Santos, Valdemir A. dos, E-mail: valdemir.alexandre@pq.cnpq.b [Universidade Catolica de Pernambuco, Recife, PE (Brazil). Centro de Ciencia e Tecnologia

    2009-07-01

    A process of Fluidized Cracking Catalytic (FCC) was developed by our research group. A cold model FCC unit, in laboratory scale, was used for obtaining of the data relative to the following parameters: air flow, system pressure, riser inlet pressure, rise outlet pressure, pressure drop in the riser, motor speed of catalyst injection and density. The measured of the density is made by gamma ray transmission. For the fact of the process of FCC not to have a database until then, the present work supplied this deficiency with the implementation of a database in connection with the Matlab software. The data from the FCC unit (laboratory model) are obtained as spreadsheet of the MS-Excel software. These spreadsheets were treated before importing them as database tables. The application of the process of normalization of database and the analysis done with the MS-Access in these spreadsheets treated revealed the need of an only relation (table) for to represent the database. The Database Manager System (DBMS) chosen has been the MS-Access by to satisfy our flow of data. The next step was the creation of the database, being built the table of data, the action query, selection query and the macro for to import data from the unit FCC in study. Also an interface between the application 'Database Toolbox' (Matlab2008a) and the database was created. This was obtained through the drivers ODBC (Open Data Base Connectivity). This interface allows the manipulation of the database by the users operating in the Matlab. (author)

  8. Is small-scale irrigation an efficient pro-poor strategy in the upper Limpopo Basin in Mozambique?

    Science.gov (United States)

    Ducrot, Raphaelle

    2017-08-01

    In Sub-Saharan Africa, there is evidence that households with access to small-scale irrigation are significantly less poor than households that do not have access to irrigation. However, private motopumps tend to be distributed inequitably. This paper investigates the success of explicit pro-poor interventions with emphasis on small-scale irrigation in the semi-arid Limpopo Basin in Mozambique. It reveals that high irrigation costs are progressively excluding the poor, who are unable to generate a cash income from other activities they need to fund irrigation. In addition, the operation of collective schemes involving the poor is being jeopardized by the development of private irrigation schemes, which benefit from hidden subsidies appropriated by local elites. This results in unequal access to irrigation, which can cause resentment at community level. This weakens community cohesiveness, as well as communities' capacities for collective action and coordination, which are crucial for collective irrigation.

  9. Fluidization behavior in a circulating slugging fluidized bed reactor. Part I : residence time and residence time distribution of polyethylene solids

    NARCIS (Netherlands)

    Putten, van I.C.; Sint Annaland, van M.; Weickert, G.

    2007-01-01

    Square nosed slugging fluidization behavior in a circulating fluidized bed riser using a polyethylene powder with a very wide particle size distribution was studied. In square nosed slugging fluidization the extent of mixing of particles of different size depends on the riser diameter, gas velocity,

  10. Fluidization behavior in a circulating slugging fluidized bed reactor. Part I: Residence time and residence time distribution of polyethylene solids

    NARCIS (Netherlands)

    van Putten, I.C.; van Sint Annaland, M.; Weickert, G.

    2007-01-01

    Square nosed slugging fluidization behavior in a circulating fluidized bed riser using a polyethylene powder with a very wide particle size distribution was studied. In square nosed slugging fluidization the extent of mixing of particles of different size depends on the riser diameter, gas velocity,

  11. Big Data solutions on a small scale: Evaluating accessible high-performance computing for social research

    Directory of Open Access Journals (Sweden)

    Dhiraj Murthy

    2014-11-01

    Full Text Available Though full of promise, Big Data research success is often contingent on access to the newest, most advanced, and often expensive hardware systems and the expertise needed to build and implement such systems. As a result, the accessibility of the growing number of Big Data-capable technology solutions has often been the preserve of business analytics. Pay as you store/process services like Amazon Web Services have opened up possibilities for smaller scale Big Data projects. There is high demand for this type of research in the digital humanities and digital sociology, for example. However, scholars are increasingly finding themselves at a disadvantage as available data sets of interest continue to grow in size and complexity. Without a large amount of funding or the ability to form interdisciplinary partnerships, only a select few find themselves in the position to successfully engage Big Data. This article identifies several notable and popular Big Data technologies typically implemented using large and extremely powerful cloud-based systems and investigates the feasibility and utility of development of Big Data analytics systems implemented using low-cost commodity hardware in basic and easily maintainable configurations for use within academic social research. Through our investigation and experimental case study (in the growing field of social Twitter analytics, we found that not only are solutions like Cloudera’s Hadoop feasible, but that they can also enable robust, deep, and fruitful research outcomes in a variety of use-case scenarios across the disciplines.

  12. Analysis of BY-106 pump pit cover plate

    International Nuclear Information System (INIS)

    Coverdell, B.L.

    1994-01-01

    A new cover for the pump pit of Tank 241-BY-106 has been designed to allow the rotary core exhauster to be hooked up without requiring pit entry, riser modification, or equipment removal. The new pit cover is necessary to allow installation of two risers for reducing exposure, contamination, and waste. Computer analysis indicates that the safety margin of the pit cover plate with two risers is adequate. The computer stress model and input files are attached. The pit cover plate is a replacement for an existing plate; therefore seismic and wind loads were considered for the plate only

  13. Lexical semantic access and letter access are involved in different aspects of reading

    DEFF Research Database (Denmark)

    Poulsen, Mads

    ). In this subset sample, both letter access and lexical access accounted for unique variance in reading fluency. The pattern of effects for lexical access did not change by controlling for serial rapid naming (RAN). Conclusions: The results suggest that letter access and lexical access are important for different......Purpose: This study investigated the effects of lexical access speed and letter access speed on reading fluency and reading comprehension. We hypothesized that 1) letter access speed would correlate with reading fluency but not comprehension, while 2) lexical access speed would influence reading...... comprehension. For readers who are struggling with recoding, most of the reading effort is probably tied up with recoding, leaving little to be explained by lexical access. Therefore we expected that 3) lexical access speed would primarily predict reading fluency for readers who were no longer struggling...

  14. Overview of Emic Triggered Chorus Emissions in Cluster Data

    Science.gov (United States)

    Grison, B.; Pickett, J. S.; Omura, Y.; Santolik, O.; Engebretson, M. J.; Dandouras, I. S.; Masson, A.; Decreau, P. M.; Adrian, M. L.; Cornilleau Wehrlin, N.

    2010-12-01

    Electromagnetic ion cyclotron (EMIC) triggered emissions have been recently observed onboard the Cluster spacecraft close to the plasmapause in the equatorial region of the magnetosphere (Pickett et al., 2010). The nonlinear mechanism of the wave amplification is the same as for the well known whistler-mode chorus emissions (Omura et al., 2010). The EMIC triggered emissions appear as risers: electromagnetic structures that have a positive frequency drift with time. They can thus be considered as the EMIC analogue of rising frequency whistler-mode chorus emissions. In addition, they propagate away from the magnetic equator. These EMIC risers are not common in Cluster data. We present an overview of the properties of all the identified cases. Risers can be sorted out in two groups: in the first one the starting frequency of EMIC emissions is close to one half of the local proton gyrofrequency and the risers have a clear left-hand polarization. In the second group the risers have an opposite polarization with a starting frequency close to one half of the He+ gyrofrequency. Most of the cases have been detected close to 22 MLT (magnetic local time). This dependence will be investigated to determine if it is linked to the orbit effects or if there is a physical cause.

  15. Parametric study on the behavior of an innovative subsurface tension leg platform in ultra-deep water

    Science.gov (United States)

    Zhen, Xing-wei; Huang, Yi

    2017-10-01

    This study focuses on a new technology of Subsurface Tension Leg Platform (STLP), which utilizes the shallowwater rated well completion equipment and technology for the development of large oil and gas fields in ultra-deep water (UDW). Thus, the STLP concept offers attractive advantages over conventional field development concepts. STLP is basically a pre-installed Subsurface Sea-star Platform (SSP), which supports rigid risers and shallow-water rated well completion equipment. The paper details the results of the parametric study on the behavior of STLP at a water depth of 3000 m. At first, a general description of the STLP configuration and working principle is introduced. Then, the numerical models for the global analysis of the STLP in waves and current are presented. After that, extensive parametric studies are carried out with regarding to SSP/tethers system analysis, global dynamic analysis and riser interference analysis. Critical points are addressed on the mooring pattern and riser arrangement under the influence of ocean current, to ensure that the requirements on SSP stability and riser interference are well satisfied. Finally, conclusions and discussions are made. The results indicate that STLP is a competitive well and riser solution in up to 3000 m water depth for offshore petroleum production.

  16. Drivers Act behind Forming Strategic Alliances between Large and Small Players- The Case of Small Players in the Telecommunication Industry

    OpenAIRE

    Sultana, Kazi Afroza

    2016-01-01

    Background: Strategic alliances enable businesses to gain competitive advantage by providing access to the each other s resources which can be utilized to ensure the business profitability of the firms in the alliance. Telecommunication industry is dominated by large players, such as Mobile Network Operators. In contrary, comparatively small players, such as Mobile Virtual Network Operators, are struggling to sustain themselves in the business. Although a lot of literature is present on strat...

  17. Disparities in Geographic Accessibility of National Cancer Institute Cancer Centers in the United States.

    Science.gov (United States)

    Xu, Yanqing; Fu, Cong; Onega, Tracy; Shi, Xun; Wang, Fahui

    2017-11-11

    The National Cancer Institute (NCI) Cancer Centers form the backbone of the cancer care system in the United States since their inception in the early 1970s. Most studies on their geographic accessibility used primitive measures, and did not examine the disparities across urbanicity or demographic groups. This research uses an advanced accessibility method, termed "2-step floating catchment area (2SFCA)" and implemented in Geographic Information Systems (GIS), to capture the degree of geographic access to NCI Cancer Centers by accounting for competition intensity for the services and travel time between residents and the facilities. The results indicate that urban advantage is pronounced as the average accessibility is highest in large central metro areas, declines to large fringe metro, medium metro, small metro, micropolitan and noncore rural areas. Population under the poverty line are disproportionally concentrated in lower accessibility areas. However, on average Non-Hispanic White have the lowest geographic accessibility, followed by Hispanic, Non-Hispanic Black and Asian, and the differences are statistically significant. The "reversed racial disadvantage" in NCI Cancer Center accessibility seems counterintuitive but is consistent with an influential prior study; and it is in contrast to the common observation of co-location of concentration of minority groups and people under the poverty line.

  18. The Livelihoods of Micro and Small Enterprise Operators in a District ...

    African Journals Online (AJOL)

    The Sustainable Livelihoods Framework (SLF) presupposes the outcomes of any livelihood strategy, including working in micro and small enterprises, the results of interplay of context, access to and level of different sorts of assets, and policies and institutions. Targeting those MSE operators working in Woreda 1 of Lideta ...

  19. Public Access and Open Access: Is There a Difference? | Poster

    Science.gov (United States)

    By Robin Meckley, Contributing Writer, and Tracie Frederick, Guest Writer Open access and public access—are they different concepts or are they the same? What do they mean for the researchers at NCI at Frederick? “Open-access (OA) literature is digital, online, free of charge, and free of most copyright and licensing restrictions. What makes it possible is the Internet and the consent of the author or copyright-holder,” according to an open access website maintained by Peter Suber, director, Harvard Open Access Project.

  20. Moving toward a universally accessible web: Web accessibility and education.

    Science.gov (United States)

    Kurt, Serhat

    2017-12-08

    The World Wide Web is an extremely powerful source of information, inspiration, ideas, and opportunities. As such, it has become an integral part of daily life for a great majority of people. Yet, for a significant number of others, the internet offers only limited value due to the existence of barriers which make accessing the Web difficult, if not impossible. This article illustrates some of the reasons that achieving equality of access to the online world of education is so critical, explores the current status of Web accessibility, discusses evaluative tools and methods that can help identify accessibility issues in educational websites, and provides practical recommendations and guidelines for resolving some of the obstacles that currently hinder the achievability of the goal of universal Web access.

  1. Caractérisation des peuplements ligneux des parcs à Faidherbia ...

    African Journals Online (AJOL)

    SARAH

    31 oct. 2015 ... Objectif : cette étude vise à caractériser les peuplements ligneux des parcs à Faidherbia albida .... domaine Sud-Sahélien Central dominé par les ... caractériser le climat. ..... Surface terrière (St) : La surface terrière globale ou.

  2. Distributed generation in small remote Northern communities

    International Nuclear Information System (INIS)

    Malcolm, D.G.

    2012-01-01

    The presentation discusses the physical and social challenges of reliable and environmentally sound electricity generation in remote northern communities in Canada. There are several hundred remote communities in the boreal region of Canada and throughout the Arctic. Electrical energy requirements are usually a few megawatts. Access to some Arctic remote communities is by air and small water craft only, except when winters are cold enough for winter roads to be constructed for a few weeks each year. These communities, as well as new mining operations and their camp communities, provide a market segment for small reactors. However, there are social acceptance hurdles to be addressed. Trust-building is a must when working with First Nations, Metis, and Inuit communities, and this requires community presence long before proposals for new generation facilities are presented.

  3. Distributed generation in small remote Northern communities

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm, D.G. [Yellowknife, North West Territories (Canada)

    2012-07-01

    The presentation discusses the physical and social challenges of reliable and environmentally sound electricity generation in remote northern communities in Canada. There are several hundred remote communities in the boreal region of Canada and throughout the Arctic. Electrical energy requirements are usually a few megawatts. Access to some Arctic remote communities is by air and small water craft only, except when winters are cold enough for winter roads to be constructed for a few weeks each year. These communities, as well as new mining operations and their camp communities, provide a market segment for small reactors. However, there are social acceptance hurdles to be addressed. Trust-building is a must when working with First Nations, Metis, and Inuit communities, and this requires community presence long before proposals for new generation facilities are presented.

  4. Single access laparoscopic nephrectomy

    Directory of Open Access Journals (Sweden)

    Jay D Raman

    2008-01-01

    Full Text Available Laparoscopic nephrectomy has assumed a central role in the management of benign and malignant kidney diseases. While laparoscopy is less morbid than open surgery, it still requires several incisions each at least 1-2 cm in length. Each incision carries morbidity risks of bleeding, hernia and/or internal organ damage, and incrementally decreases cosmesis. An alternative to conventional laparoscopy is single access or keyhole surgery, which utilizes magnetic anchoring and guidance system (MAGS technology or articulating laparoscopic instruments. These technical innovations obviate the need to externally space trocars for triangulation, thus allowing for the creation of a small, solitary portal of entry into the abdomen. Laboratory and early clinical series demonstrate feasibility as well as safe and successful completion of keyhole nephrectomy. Future work is necessary to improve existing instrumentation, increase clinical experience, assess benefits of this surgical approach, and explore other potential applications for this technique.

  5. Access Customized Forms

    OpenAIRE

    Cosma Emil; Jeflea Victor

    2010-01-01

    By using Word, Excel or PowerPoint one can automate routine operations using the VBA language (Visual Basic for Applications). This language is also used in Access, allowing access to data stored in tables or queries. Thus, Access and VBA resources can be used together. Access is designed for programming forms and reports (among other things), so there won’t be found any of the VBA editor’s specific forms.

  6. Simple re-instantiation of small databases using cloud computing.

    Science.gov (United States)

    Tan, Tin Wee; Xie, Chao; De Silva, Mark; Lim, Kuan Siong; Patro, C Pawan K; Lim, Shen Jean; Govindarajan, Kunde Ramamoorthy; Tong, Joo Chuan; Choo, Khar Heng; Ranganathan, Shoba; Khan, Asif M

    2013-01-01

    Small bioinformatics databases, unlike institutionally funded large databases, are vulnerable to discontinuation and many reported in publications are no longer accessible. This leads to irreproducible scientific work and redundant effort, impeding the pace of scientific progress. We describe a Web-accessible system, available online at http://biodb100.apbionet.org, for archival and future on demand re-instantiation of small databases within minutes. Depositors can rebuild their databases by downloading a Linux live operating system (http://www.bioslax.com), preinstalled with bioinformatics and UNIX tools. The database and its dependencies can be compressed into an ".lzm" file for deposition. End-users can search for archived databases and activate them on dynamically re-instantiated BioSlax instances, run as virtual machines over the two popular full virtualization standard cloud-computing platforms, Xen Hypervisor or vSphere. The system is adaptable to increasing demand for disk storage or computational load and allows database developers to use the re-instantiated databases for integration and development of new databases. Herein, we demonstrate that a relatively inexpensive solution can be implemented for archival of bioinformatics databases and their rapid re-instantiation should the live databases disappear.

  7. Access to finance for innovation: the role of venture capital and the stock market

    NARCIS (Netherlands)

    Bogliacino, F.; Lucchese, M.

    2011-01-01

    Financial constraints for young and small firms can prevent them from contributing to innovation and the creation of new jobs. The paper analyzes two of the several institutional mechanisms implemented to overcome that hurdle: the development of the venture capital market and access to the stock

  8. A Vulnerability Assessment of the U.S. Small Business B2C E-Commerce Network Systems

    Science.gov (United States)

    Zhao, Jensen J.; Truell, Allen D.; Alexander, Melody W.; Woosley, Sherry A.

    2011-01-01

    Objective: This study assessed the security vulnerability of the U.S. small companies' business-to-consumer (B2C) e-commerce network systems. Background: As the Internet technologies have been changing the way business is conducted, the U.S. small businesses are investing in such technologies and taking advantage of e-commerce to access global…

  9. Open access

    CERN Document Server

    Suber, Peter

    2012-01-01

    The Internet lets us share perfect copies of our work with a worldwide audience at virtually no cost. We take advantage of this revolutionary opportunity when we make our work "open access": digital, online, free of charge, and free of most copyright and licensing restrictions. Open access is made possible by the Internet and copyright-holder consent, and many authors, musicians, filmmakers, and other creators who depend on royalties are understandably unwilling to give their consent. But for 350 years, scholars have written peer-reviewed journal articles for impact, not for money, and are free to consent to open access without losing revenue. In this concise introduction, Peter Suber tells us what open access is and isn't, how it benefits authors and readers of research, how we pay for it, how it avoids copyright problems, how it has moved from the periphery to the mainstream, and what its future may hold. Distilling a decade of Suber's influential writing and thinking about open access, this is the indispe...

  10. HF Radio Astronomy from a Small Satellite

    Science.gov (United States)

    2016-06-15

    SSC16-XI-03 HF Radio Astronomy from a Small Satellite Frank C. Robey1, Mary Knapp2, Alan J. Fenn1, Mark Silver1, Kerry Johnson1 Frank J. Lind3...frequency end of the electromagnetic spectrum (below 15 MHz) is one of the least explored windows in observational astronomy . Observations at these...pdf. [Accessed: 17-Oct-2015]. 3. G. Hallinan, “The Owens Valley LWA,” in Exascale Radio Astronomy , 2014, vol. 2. 4. C. J. Lonsdale, R. J. Cappallo

  11. From spatial to social accessibility: How socio-economic factors can affect accessibility?

    OpenAIRE

    Mercier , Aurélie

    2016-01-01

    The concept of accessibility cannot only focus on " spatial accessibility " measurement but has to integer a " social accessibility " level to take into account individual inequalities and socioeconomic disparities to access to urban opportunities. In this context, this contribution focuses on socioeconomic disparities integration on accessibility measurement, considering the Lyon case study. The paper is divided into three parts The first part aims to present a method for integrating the soc...

  12. Accessibility

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis

    2017-01-01

    This contribution is timely as it addresses accessibility in regards system hardware and software aligned with introduction of the Twenty-First Century Communications and Video Accessibility Act (CVAA) and adjoined game industry waiver that comes into force January 2017. This is an act created...... by the USA Federal Communications Commission (FCC) to increase the access of persons with disabilities to modern communications, and for other purposes. The act impacts advanced communications services and products including text messaging; e-mail; instant messaging; video communications; browsers; game...... platforms; and games software. However, the CVAA has no legal status in the EU. This text succinctly introduces and questions implications, impact, and wider adoption. By presenting the full CVAA and game industry waiver the text targets to motivate discussions and further publications on the subject...

  13. Moving Out of the Office: Removing Barriers to Access to Psychiatrists.

    Science.gov (United States)

    Paris, Joel; Goldbloom, David; Kurdyak, Paul

    2015-09-01

    Our paper offers a perspective on barriers to access to psychiatric care. Research shows that access depends not simply on the total number of trained specialists but also on their kind of practice. In some large cities, some practitioners follow a small number of patients in long-term psychotherapy, a practice supported by government insurance, which places no limits on the number of sessions or treatment duration. The problem is that long-term psychotherapy, despite a rich tradition in psychiatry, is not an evidence-based treatment. This review recommends a model in which psychiatrists spend more time in consultation with primary care professionals, in acute care for patients with severe mental illness, and in briefer, more cost-effective forms of psychotherapy.

  14. The small and rural academic library leveraging resources and overcoming limitations

    CERN Document Server

    Davis Kendrick, Kaetrena

    2016-01-01

    Through the use of case studies, research, and practical interviews, The Small or Rural Academic Library: Leveraging Resources and Overcoming Limitations explores how academic librarians in such environments can keep pace with, create, and improve modern library practices and services, network with colleagues, and access continuing education and professional development opportunities.

  15. Interference-Robust Air Interface for 5G Ultra-dense Small Cells

    DEFF Research Database (Denmark)

    Tavares, Fernando Menezes Leitão; Berardinelli, Gilberto; Mahmood, Nurul Huda

    2016-01-01

    An ultra-dense deployment of small cells is foreseen as the solution to cope with the exponential increase of the data rate demand targeted by the 5th Generation (5G) radio access technology. In this article, we propose an interference-robust air interface built upon the usage of advanced receivers...

  16. Entropy generation by nanofluid with variable thermal conductivity ...

    African Journals Online (AJOL)

    The entropy generation by nanofluid with variable thermal conductivity and viscosity of assisted convective flow across a riser pipe of a horizontal flat plate solar collector is investigated numerically. The water based nanofluid with copper nanoparticles is used as the working fluid inside the fluid passing riser pipe.

  17. SCRAM: a pipeline for fast index-free small RNA read alignment and visualization.

    Science.gov (United States)

    Fletcher, Stephen J; Boden, Mikael; Mitter, Neena; Carroll, Bernard J

    2018-03-15

    Small RNAs play key roles in gene regulation, defense against viral pathogens and maintenance of genome stability, though many aspects of their biogenesis and function remain to be elucidated. SCRAM (Small Complementary RNA Mapper) is a novel, simple-to-use short read aligner and visualization suite that enhances exploration of small RNA datasets. The SCRAM pipeline is implemented in Go and Python, and is freely available under MIT license. Source code, multiplatform binaries and a Docker image can be accessed via https://sfletc.github.io/scram/. s.fletcher@uq.edu.au. Supplementary data are available at Bioinformatics online.

  18. Making Small Towns Visible in Europe: The Case of Cittaslow Network – The Strategy Based on Sustainable Development

    Directory of Open Access Journals (Sweden)

    Alicja K. ZAWADZKA

    2017-12-01

    Full Text Available The aim of the article is to identify strategies for the development and promotion of small towns based on the implementation of the principles of sustainable development, using both endogenous social capital, unique material values of cultural heritage as well as values of the natural environment. The strategy described in this article is a derivative of the benefi ts of membership in the Cittaslow global network, the peripheral location of small towns to metropolises as well as other alternative values of small towns not accessible to large cities. It has been shown that Cittaslow can be both an indicator of sustainable development, an activator of sustainable tourism as well as an instrument for raising awareness of the endogenous capital of small towns. The background to the considerations on potential implications of accession to Cittaslow is the analysis of contemporary international networks of cities whose priority or one of the key objectives is to act in accordance with the principles of sustainable development.

  19. DENSE MULTIPHASE FLOW SIMULATION: CONTINUUM MODEL FOR POLY-DISPERSED SYSTEMS USING KINETIC THEORY

    Energy Technology Data Exchange (ETDEWEB)

    Moses Bogere

    2011-08-31

    The overall objective of the project was to verify the applicability of the FCMOM approach to the kinetic equations describing the particle flow dynamics. For monodispersed systems the fundamental equation governing the particle flow dynamics is the Boltzmann equation. During the project, the FCMOM was successfully applied to several homogeneous and in-homogeneous problems in different flow regimes, demonstrating that the FCMOM has the potential to be used to solve efficiently the Boltzmann equation. However, some relevant issues still need to be resolved, i.e. the homogeneous cooling problem (inelastic particles cases) and the transition between different regimes. In this report, the results obtained in homogeneous conditions are discussed first. Then a discussion of the validation results for in-homogeneous conditions is provided. And finally, a discussion will be provided about the transition between different regimes. Alongside the work on development of FCMOM approach studies were undertaken in order to provide insights into anisotropy or particles kinetics in riser hydrodynamics. This report includes results of studies of multiphase flow with unequal granular temperatures and analysis of momentum re-distribution in risers due to particle-particle and fluid-particle interactions. The study of multiphase flow with unequal granular temperatures entailed both simulation and experimental studies of two particles sizes in a riser and, a brief discussion of what was accomplished will be provided. And finally, a discussion of the analysis done on momentum re-distribution of gas-particles flow in risers will be provided. In particular a discussion of the remaining work needed in order to improve accuracy and predictability of riser hydrodynamics based on two-fluid models and how they can be used to model segregation in risers.

  20. The Verrès Castle Access Project

    Directory of Open Access Journals (Sweden)

    Tito Berti Nulli

    2010-10-01

    Full Text Available The article describes the access project of the Verrès castle, located in Aosta Valley in Italy, underlining some urban and transport planning and design elements. This project constitute in fact an interesting example of integration between transport infrastructure planning and design with urban planning strategy for tourism development. The transport infrastructure (in this case a vertical lift for tourism use has furthermore a deep attention to the landscape and social contest and a good architectural design. The Verrès castle access project represents and interesting example of sustainable mobility and of touristic area accessibility which is strong integrated with urban renewal and territorial development. The feasibility study, financed by the Verrès municipality, is part of a the INTERREG IIIA ACOLTRA Project financed by Italy and France with the aim of creating a network of transnational tourist itineraries. Through this initiative Aosta Valley and Haute-Savoy are developing a common tourism strategy that intends to promote cultural heritage and tourism mobility through the RITT (Reseaux d’Itineraires Touristiques Transfrontalieres. In this contest of intervention the study for the accessibility of the Verrès castle is inserted, with the aim of designing a mobility infrastructure for the main attraction of the valley and at the same of strengthening the appeal of tourist attraction of the whole area. The project is located in the small city of Verrés, that lies at 390m, on the banks of the river Evançon. As many of the Valdostani municipalities is characterized by several small urban centers, which are located in a around 8kmq, in a territory where live 2.700 inhabitants. The feasibility study examines three different alternative for a lift that should connect the Verrès centre with the castle. In particular different transport technology (inclined and vertical lift and several path alternatives have been evaluated. The final

  1. Demystifying Open Access

    International Nuclear Information System (INIS)

    Mele, Salvatore

    2007-01-01

    The tenets of Open Access are to grant anyone, anywhere and anytime free access to the results of scientific research. HEP spearheaded the Open Access dissemination of scientific results with the mass mailing of preprints in the pre-WWW era and with the launch of the arXiv preprint system at the dawn of the '90s. The HEP community is now ready for a further push to Open Access while retaining all the advantages of the peer-review system and, at the same time, bring the spiralling cost of journal subscriptions under control. I will present a possible plan for the conversion to Open Access of HEP peer-reviewed journals, through a consortium of HEP funding agencies, laboratories and libraries: SCOAP3 (Sponsoring Consortium for Open Access Publishing in Particle Physics). SCOAP3 will engage with scientific publishers towards building a sustainable model for Open Access publishing, which is as transparent as possible for HEP authors. The current system in which journals income comes from subscription fees is replaced with a scheme where SCOAP3 compensates publishers for the costs incurred to organise the peer-review service and give Open Access to the final version of articles. SCOAP3 will be funded by all countries active in HEP under a 'fair share' scenario, according to their production of HEP articles. In this talk I will present a short overview of the history of Open Access in HEP, the details of the SCOAP3 model and the outlook for its implementation.

  2. Spatial Accessibility of Primary Care in England: A Cross-Sectional Study Using a Floating Catchment Area Method.

    Science.gov (United States)

    Bauer, Jan; Müller, Ruth; Brüggmann, Dörthe; Groneberg, David A

    2017-07-07

    To analyze the general practitioners (GPs) with regard to the degree of urbanization, social deprivation, general health, and disability. Small area population data and GP practice data in England. We used a floating catchment area method to measure spatial GP accessibility with regard to the degree of urbanization, social deprivation, general health, and disability. Data were collected from the Office for National Statistics and the general practice census and analyzed using a geographic information system. In all, 25.8 percent of the population in England lived in areas with a significant low GP accessibility (mean z-score: -4.2); 27.6 percent lived in areas with a significant high GP accessibility (mean z-score: 7.7); 97.8 percent of high GP accessibility areas represented urban areas, and 31.1 percent of low GP accessibility areas represented rural areas (correlation of accessibility and urbanity: r = 0.59; psocial deprivation was present (r = -0.19; paccessibility throughout England. However, socially deprived areas did not have poorer spatial access to GPs. © Health Research and Educational Trust.

  3. Small scale agriculture, marginal conditions and market access: impacts on natural resources and farmers' welfare

    NARCIS (Netherlands)

    Cavatassi, R.

    2010-01-01

    Keywords: small-scale farmers, food security, impact evaluation, Ecuador, Ethiopia, crop choice, social capital, crop genetic diversity, pesticides.

    Numerous are the obstacles and difficulties smallholder farmers from developing countries have to face to achieve food security or improve

  4. Patient-reported access to primary care in Ontario: effect of organizational characteristics.

    Science.gov (United States)

    Muggah, Elizabeth; Hogg, William; Dahrouge, Simone; Russell, Grant; Kristjansson, Elizabeth; Muldoon, Laura; Devlin, Rose Anne

    2014-01-01

    To describe patient-reported access to primary health care across 4 organizational models of primary care in Ontario, and to explore how access is associated with patient, provider, and practice characteristics. Cross-sectional survey. One hundred thirty-seven randomly selected primary care practices in Ontario using 1 of 4 delivery models (fee for service, established capitation, reformed capitation, and community health centres). Patients included were at least 18 years of age, were not severely ill or cognitively impaired, were not known to the survey administrator, had consenting providers at 1 of the participating primary care practices, and were able to communicate in English or French either directly or through a translator. Patient-reported access was measured by a 4-item scale derived from the previously validated adult version of the Primary Care Assessment Tool. Questions were asked about physician availability during and outside of regular office hours and access to health information via telephone. Responses to the scale were normalized, with higher scores reflecting greater patient-reported access. Linear regressions were used to identify characteristics independently associated with access to care. Established capitation model practices had the highest patient-reported access, although the difference in scores between models was small. Our multilevel regression model identified several patient factors that were significantly (P = .05) associated with higher patient-reported access, including older age, female sex, good-to-excellent self-reported health, less mental health disability, and not working. Provider experience (measured as years since graduation) was the only provider or practice characteristic independently associated with improved patient-reported access. This study adds to what is known about access to primary care. The study found that established capitation models outperformed all the other organizational models, including reformed

  5. An Authentication and Key Management Mechanism for Resource Constrained Devices in IEEE 802.11-based IoT Access Networks

    OpenAIRE

    Kim, Ki-Wook; Han, Youn-Hee; Min, Sung-Gi

    2017-01-01

    Many Internet of Things (IoT) services utilize an IoT access network to connect small devices with remote servers. They can share an access network with standard communication technology, such as IEEE 802.11ah. However, an authentication and key management (AKM) mechanism for resource constrained IoT devices using IEEE 802.11ah has not been proposed as yet. We therefore propose a new AKM mechanism for an IoT access network, which is based on IEEE 802.11 key management with the IEEE 802.1X aut...

  6. SearchSmallRNA: a graphical interface tool for the assemblage of viral genomes using small RNA libraries data.

    Science.gov (United States)

    de Andrade, Roberto R S; Vaslin, Maite F S

    2014-03-07

    Next-generation parallel sequencing (NGS) allows the identification of viral pathogens by sequencing the small RNAs of infected hosts. Thus, viral genomes may be assembled from host immune response products without prior virus enrichment, amplification or purification. However, mapping of the vast information obtained presents a bioinformatics challenge. In order to by pass the need of line command and basic bioinformatics knowledge, we develop a mapping software with a graphical interface to the assemblage of viral genomes from small RNA dataset obtained by NGS. SearchSmallRNA was developed in JAVA language version 7 using NetBeans IDE 7.1 software. The program also allows the analysis of the viral small interfering RNAs (vsRNAs) profile; providing an overview of the size distribution and other features of the vsRNAs produced in infected cells. The program performs comparisons between each read sequenced present in a library and a chosen reference genome. Reads showing Hamming distances smaller or equal to an allowed mismatched will be selected as positives and used to the assemblage of a long nucleotide genome sequence. In order to validate the software, distinct analysis using NGS dataset obtained from HIV and two plant viruses were used to reconstruct viral whole genomes. SearchSmallRNA program was able to reconstructed viral genomes using NGS of small RNA dataset with high degree of reliability so it will be a valuable tool for viruses sequencing and discovery. It is accessible and free to all research communities and has the advantage to have an easy-to-use graphical interface. SearchSmallRNA was written in Java and is freely available at http://www.microbiologia.ufrj.br/ssrna/.

  7. Overview: Routes to Open Access

    OpenAIRE

    Tullney, Marco; van Wezenbeek, Wilma

    2017-01-01

    Slides of an overview presentation given at a CESAER workshop on Open Access, February 2nd, 2017, in Brussels Cover major routes to more open access as discussed in the Task Force Open Science of CESAER: (national) open access strategies open access mandates open access incentives open access awareness open access publishing open access infrastructure

  8. Biodegradation of 2,4,6-trichlorophenol in a packed-bed biofilm reactor equipped with an internal net draft tube riser for aeration and liquid circulation

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-De Jesus, A.; Romano-Baez, F.J.; Leyva-Amezcua, L.; Juarez-Ramirez, C.; Ruiz-Ordaz, N. [Departamento de Ingenieria Bioquimica, Escuela Nacional de Ciencias Biologicas, IPN. Prol. Carpio y Plan de Ayala, Colonia Santo Tomas, s/n. CP 11340, Mexico, D.F. (Mexico); Galindez-Mayer, J. [Departamento de Ingenieria Bioquimica, Escuela Nacional de Ciencias Biologicas, IPN. Prol. Carpio y Plan de Ayala, Colonia Santo Tomas, s/n. CP 11340, Mexico, D.F. (Mexico)], E-mail: cmayer@encb.ipn.mx

    2009-01-30

    For the aerobic biodegradation of the fungicide and defoliant 2,4,6-trichlorophenol (2,4,6-TCP), a bench-scale packed-bed bioreactor equipped with a net draft tube riser for liquid circulation and oxygenation (PB-ALR) was constructed. To obtain a high packed-bed volume relative to the whole bioreactor volume, a high A{sub D}/A{sub R} ratio was used. Reactor's downcomer was packed with a porous support of volcanic stone fragments. PB-ALR hydrodynamics and oxygen mass transfer behavior was evaluated and compared to the observed behavior of the unpacked reactor operating as an internal airlift reactor (ALR). Overall gas holdup values {epsilon}{sub G}, and zonal oxygen mass transfer coefficients determined at various airflow rates in the PB-ALR, were higher than those obtained with the ALR. When comparing mixing time values obtained in both cases, a slight increment in mixing time was observed when reactor was operated as a PB-ALR. By using a mixed microbial community, the biofilm reactor was used to evaluate the aerobic biodegradation of 2,4,6-TCP. Three bacterial strains identified as Burkholderia sp., Burkholderia kururiensis and Stenotrophomonas sp. constituted the microbial consortium able to cometabolically degrade the 2,4,6-TCP, using phenol as primary substrate. This consortium removed 100% of phenol and near 99% of 2,4,6-TCP. Mineralization and dehalogenation of 2,4,6-TCP was evidenced by high COD removal efficiencies ({approx}95%), and by the stoichiometric release of chloride ions from the halogenated compound ({approx}80%). Finally, it was observed that the microbial consortium was also capable to metabolize 2,4,6-TCP without phenol as primary substrate, with high removal efficiencies (near 100% for 2,4,6-TCP, 92% for COD and 88% for chloride ions)

  9. V4: The Small Angle Scattering Instrument (SANS at BER II

    Directory of Open Access Journals (Sweden)

    Uwe Keiderling

    2016-11-01

    Full Text Available V4 is a small-angle neutron scatting instrument with an accessible range of scattering vector 0.01 nm-1 < Q < 8.5 nm-1. Outstanding features of the instrument are the polarized neutron option and the list mode data acquisition, allowing for time-resolved measurements with µs time resolution.

  10. Accessing Electronic Journals.

    Science.gov (United States)

    McKay, Sharon Cline

    1999-01-01

    Discusses issues librarians need to consider when providing access to electronic journals. Topics include gateways; index and abstract services; validation and pay-per-view; title selection; integration with OPACs (online public access catalogs)or Web sites; paper availability; ownership versus access; usage restrictions; and services offered…

  11. Structural evaluation of W-211 flexible receiver platforms and tank pit walls

    International Nuclear Information System (INIS)

    Shrivastava, H.P.

    1997-01-01

    This document is a structural analysis of the Flexible Receiver Platforms and the tank-pit wall during removal of equipment and during a accidental drop of that equipment. The platform and the pit walls must withstand a accidental drop of a mixer and transfer pumps in specific pits in tanks 102-AP and 104-AP. A mixer pump will be removed from riser 11 in pit 2A on tank 241-AP-102. A transfer pump will be removed from riser 13 in pit 2D on tank 241-AP-102 and another transfer pump will be removed from riser 3A in pit 4A on tank 241-AP-104

  12. Core disruptive accident margin seal

    International Nuclear Information System (INIS)

    Golden, M.P.

    1979-01-01

    An apparatus for sealing the annulus defined within a substantially cylindrical rotatable riser assembly and plug combination of a nuclear reactor closure head is described. The apparatus comprises an inflatable sealing mechanism disposed in one portion of the riser assembly near the annulus such that upon inflation the sealing mechanism is radially actuated against the other portion of the riser assembly thereby sealing the annulus. The apparatus further comprises a connecting mechanism which places one end of the sealing mechanism in fluid communication with the reactor cover gas so that overpressurization of the reactor cover gas will increase the radial actuation of the sealing mechanism thus enhancing sealing of the annulus

  13. Accessing memory

    Science.gov (United States)

    Yoon, Doe Hyun; Muralimanohar, Naveen; Chang, Jichuan; Ranganthan, Parthasarathy

    2017-09-26

    A disclosed example method involves performing simultaneous data accesses on at least first and second independently selectable logical sub-ranks to access first data via a wide internal data bus in a memory device. The memory device includes a translation buffer chip, memory chips in independently selectable logical sub-ranks, a narrow external data bus to connect the translation buffer chip to a memory controller, and the wide internal data bus between the translation buffer chip and the memory chips. A data access is performed on only the first independently selectable logical sub-rank to access second data via the wide internal data bus. The example method also involves locating a first portion of the first data, a second portion of the first data, and the second data on the narrow external data bus during separate data transfers.

  14. Knowledge of disease and access to a specialist reported by Spanish patients with ulcerative colitis. UC-LIFE survey.

    Science.gov (United States)

    Argüelles-Arias, Federico; Carpio, Daniel; Calvet, Xavier; Romero, Cristina; Cea-Calvo, Luis; Juliá, Berta; López-Sanromán, Antonio

    2017-06-01

    Education of patients with ulcerative colitis (UC) about their disease and access to a specialist are important to improve health outcomes. Our objective was to determine, by collecting information directly from the patients, their information sources and knowledge of the disease, and the options for access to the gastroenterologist. The information was collected using a printed survey handed out by 39 gastroenterologists to 15 consecutive adult patients with UC. Patients answered anonymously from their home. The responses were stratified by hospital size (> 900; 500-900; < 500 beds). A total of 585 patients received the survey and 436 responded (74.5%; mean age of 46 years [13.5], 53% men). The main information source was the specialist physician (89.2%). Between 32% and 80% of patients had areas of improvement regarding knowledge of their disease. Knowledge of the disease was better in patients from small hospitals (< 500 beds). The frequency of routine visits was also higher in small hospitals. In case of a flare-up, 60% stated they were able to contact their doctor by phone and 37%, that they could get an appointment on the same day. The percentage stating that they had to ask for an appointment and wait until their physician was available was lower in small hospitals. There are areas of improvement with regard to knowledge of their disease in patients with UC followed in hospital clinics. Patients followed in small hospitals seem to know their disease better, are followed more frequently in the clinic, and have better access in case of a flare-up.

  15. Open Access and Authors’ Rights Management: A Possibility for Theology?

    Directory of Open Access Journals (Sweden)

    Kevin L. Smith

    2009-05-01

    Full Text Available Several academic disciplines have begun to understand the benefits of open access to scholarship, both for scholars and for the general public. Scientific disciplines have led the way, partially due to the nature of scholarship in those areas and partially because they have felt the crisis in serials pricing more acutely than others. Theological studies, however, have largely been insulated from the push for open access; considering the reasons for that is the first task of this article. It is also the case, however, that the missionary impulse that stands behind much theological scholarship is a strong incentive to embrace the opportunities afforded by digital, online dissemination of research and writing. After discussing this imperative for global distribution, the bulk of the article focuses on how theological institutions, and especially their libraries, can encourage and support scholars in making their work freely accessible. Copyright issues, including the elements of a successful copyright management program, are discussed, as are some of the technological elements necessary for an efficient and discoverable open access repository. Options for licensing, both at ingestion of content and at dissemination to users are also considered. Finally, it is argued that the role of consortia and professional organizations in supporting these initiatives is especially important because of the relatively small size of so many theological institutions.

  16. Wireless Access

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Wireless Access. Wireless connect to the Base station. Easy and Convenient access. Costlier as compared to the wired technology. Reliability challenges. We see it as a complementary technology to the DSL.

  17. Transparency of Biobank Access in Canada: An Assessment of Industry Access and the Availability of Information on Access Policies and Resulting Research.

    Science.gov (United States)

    Gibson, Shannon G; Axler, Renata E; Lemmens, Trudo

    2017-12-01

    A key issue impacting public trust in biobanks is how these resources are utilized, including who is given access to biobank data and samples. To assess the conditions under which researchers are given access to Canadian biobanks, we reviewed websites and contacted Canadian biobanks to determine the availability of information on access policies and procedures; research resulting from access biobank data and samples; and conditions on private industry access to biobanks. We also conducted expert interviews with key Canadian stakeholders ( n = 11) to obtain their perspectives on biobank transparency and access policies. Among 21 Canadian biobanks, there was wide variation in the access information made publicly available, and the majority of these allowed access by industry applicants. Biobanks should be governed by the principles of transparency, accountability, and accessibility, and attention must be given to the conditions around the commercialization of biobank-based research.

  18. Mobile access to the Internet: from personal bubble to satellites

    Science.gov (United States)

    Gerla, Mario

    2001-10-01

    Mobile, wireless access and networking has emerged in the last few years as one of the most important directions of Internet growth. The popularity of mobile, and, more generally, nomadic Internet access is due to many enabling factors including: (a) emergence of meaningful applications tailored to the individual on the move; (b) small form factor and long battery life; (c) efficient middleware designed to support mobility; and, (d) efficient wireless networking technologies. A key player in the mobile Internet access is the nomad, i.e. the individual equipped with various computing and I/O gadgets (cellular phone, earphones, GPS navigator, palm pilot, beeper, portable scanner, digital camera, etc.). These devices form his/her Personal Area Network or PAN or personal bubble. The connectivity within the bubble is wireless (using for example a low cost, low power wireless LAN such as Bluetooth). The bubble can expand and contract dynamically depending on needs. It may temporarily include sensors and actuators as the nomad walks into a new environment. In this paper, we identify the need for the interconnection of the PAN with other wireless networks in order to achieve costeffective mobile access to the Internet. We will overview some key networking technologies required to support the PAN (eg, Bluetooth). We will also discuss an emerging technology, Ad Hoc wireless networking which is the natural complement of the PAN in sparsely populated areas. Finally, we will identify the need for intelligent routers to assist the mobile user in the selection of the best Internet access strategy.

  19. Foundation-Level Gulf Arab Student Response to Self-Access Learning

    Directory of Open Access Journals (Sweden)

    Diane Malcolm

    2013-12-01

    Full Text Available This article describes the role of the self-access centre at Arabian Gulf University (AGU in helping low proficiency students in our foundation year achieve the skills in English they will need to succeed in our medical college. Students’ previous training and expectations are described as well as some of the practices developed at AGU to monitor and encourage student participation in the centre. While students have generally responded well to their self-access work in our facility and endorse its role in developing their skills, they have also highlighted some areas for improvement. Although our centre is small and serves a specialized group of learners, some of the issues we face may be similar to those experienced by others in different settings and some of the solutions we have tried to find may be of interest.

  20. Professional Access 2013 programming

    CERN Document Server

    Hennig, Teresa; Hepworth, George; Yudovich, Dagi (Doug)

    2013-01-01

    Authoritative and comprehensive coverage for building Access 2013 Solutions Access, the most popular database system in the world, just opened a new frontier in the Cloud. Access 2013 provides significant new features for building robust line-of-business solutions for web, client and integrated environments.  This book was written by a team of Microsoft Access MVPs, with consulting and editing by Access experts, MVPs and members of the Microsoft Access team. It gives you the information and examples to expand your areas of expertise and immediately start to develop and upgrade projects. Exp

  1. Access 2010 Programmer's Reference

    CERN Document Server

    Hennig, Teresa; Griffith, Geoffrey L

    2010-01-01

    A comprehensive guide to programming for Access 2010 and 2007. Millions of people use the Access database applications, and hundreds of thousands of developers work with Access daily. Access 2010 brings better integration with SQL Server and enhanced XML support; this Wrox guide shows developers how to take advantage of these and other improvements. With in-depth coverage of VBA, macros, and other programming methods for building Access applications, this book also provides real-world code examples to demonstrate each topic.: Access is the leading database that is used worldwide; While VBA rem

  2. Factors influencing access to finance by SMEs in Mozambique: Case of SMEs in Maputo central business district

    OpenAIRE

    Osano, Hezron Mogaka; Languitone, Hilario

    2016-01-01

    SMEs play an important role in the economic development of Mozambique. Access to finance is important for the growth of SMEs. Thus, the purpose of the study was to establish the factors that influence access to finance by SMEs. The factors that were addressed included structure of financial sector, awareness of funding opportunities, collateral requirements, and small business support services. The target population was 2725 which comprised of 2075 staff of three Banks, namely BIM Bank, BCI B...

  3. Field Testing of a Small Water Purification System for Non-PRASA Rural Communities

    Science.gov (United States)

    Small, rural communities typically do not have adequate water purification systems to sustain their life quality and residents are exposed to pathogens present in drinking water. In Puerto Rico (PR), approximately 4% of the population does not have access to drinking water provi...

  4. Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter. Preliminary settling and resuspension testing

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fowley, M. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Miller, D. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-05-01

    The full-scale, room-temperature Hanford Tank Waste Treatment and Immobilization Plant (WTP) High-Level Waste (HLW) melter riser test system was successfully operated with silicone oil and magnetite particles at a loading of 0.1 vol %. Design and construction of the system and instrumentation, and the selection and preparation of simulant materials, are briefly reviewed. Three experiments were completed. A prototypic pour rate was maintained, based on the volumetric flow rate. Settling and accumulation of magnetite particles were observed at the bottom of the riser and along the bottom of the throat after each experiment. The height of the accumulated layer at the bottom of the riser, after the first pouring experiment, approximated the expected level given the solids loading of 0.1 vol %. More detailed observations of particle resuspension and settling were made during and after the third pouring experiment. The accumulated layer of particles at the bottom of the riser appeared to be unaffected after a pouring cycle of approximately 15 minutes at the prototypic flow rate. The accumulated layer of particles along the bottom of the throat was somewhat reduced after the same pouring cycle. Review of the time-lapse recording showed that some of the settling particles flow from the riser into the throat. This may result in a thicker than expected settled layer in the throat.

  5. QCD expectations for deep inelastic scattering at small x

    International Nuclear Information System (INIS)

    Kwiecinski, J.

    1993-01-01

    The basic QCD expectations concerning the deep inelastic scattering at low x where x is the Bjorken scaling variable are reviewed. This includes discussion of the Lipatov equation which sums the leading powers of Ln(1/x) and the shadowing effects. Phenomenological implications of the theoretical expectations for the deep inelastic lepton-hadron scattering in the small x region which will be accessible at the HERA ep collider are described. We give predictions for structure functions F 2 and F L based on the k T factorization theorem and discuss jet production in deep inelastic lepton scattering. The list of other topical problems relevant for the small x physics is given. (author). 46 refs, 7 figs

  6. Combined use of random access and ELISA analyzers in the microbiological serology laboratory

    Directory of Open Access Journals (Sweden)

    Alessandra Moroni

    2008-09-01

    Full Text Available In the last years the trend of centralizing small laboratories in large reference centers led to a careful evaluation of the diagnostic profiles. In the serology laboratory of Microbiology Unit, St. Orsola-Malpighi Hospital, Bologna, Italy the choice has been to combine random access analyzers (ARCHITECT Abbott and ELISA analyzers (BEPIII Dade Behring.

  7. JISC Open Access Briefing Paper

    OpenAIRE

    Swan, Alma

    2005-01-01

    What Open Access is. What Open Access is not. How is Open Access provided? Open Access archives or repositories. Open Access journals. Why should authors provide Open Access to their work? Further information and resources

  8. Access 2013 bible

    CERN Document Server

    Alexander, Michael

    2013-01-01

    A comprehensive reference to the updated and new features of Access 2013 As the world's most popular database management tool, Access enables you to organize, present, analyze, and share data as well as build powerful database solutions. However, databases can be complex. That's why you need the expert guidance in this comprehensive reference. Access 2013 Bible helps you gain a solid understanding of database purpose, construction, and application so that whether you're new to Access or looking to upgrade to the 2013 version, this well-rounded resource provides you with a th

  9. The Mission Accessible Near-Earth Object Survey (MANOS): Project Overview

    Science.gov (United States)

    Moskovitz, Nicholas; Polishook, David; Thomas, Cristina; Willman, Mark; DeMeo, Francesca; Mommert, Michael; Endicott, Thomas; Trilling, David; Binzel, Richard; Hinkle, Mary; Siu, Hosea; Neugent, Kathryn; Christensen, Eric; Person, Michael; Burt, Brian; Grundy, Will; Roe, Henry; Abell, Paul; Busch, Michael

    2014-11-01

    The Mission Accessible Near-Earth Object Survey (MANOS) began in August 2013 as a multi-year physical characterization survey that was awarded survey status by NOAO. MANOS will target several hundred mission-accessible NEOs across visible and near-infrared wavelengths, ultimately providing a comprehensive catalog of physical properties (astrometry, light curves, spectra). Particular focus is paid to sub-km NEOs, for which little data currently exists. These small bodies are essential to understanding the link between meteorites and asteroids, pose the most immediate impact hazard to the Earth, and are highly relevant to a variety of planetary mission scenarios. Accessing these targets is enabled through a combination of classical, queue, and target-of-opportunity observations carried out at 1- to 8-meter class facilities in both the northern and southern hemispheres. The MANOS observing strategy is specifically designed to rapidly characterize newly discovered NEOs before they fade beyond observational limits. MANOS will provide major advances in our understanding of the NEO population as a whole and for specific objects of interest. Here we present an overview of the survey, progress to date, and early science highlights including: (1) an estimate of the taxonomic distribution of spectral types for NEOs smaller than ~100 meters, (2) the distribution of rotational properties for approximately 100 previously unstudied objects, (3) models for the dynamical evolution of the overall NEO population over the past 0.5 Myr, and (4) progress in developing a new set of online tools at asteroid.lowell.edu that will enable near realtime public dissemination of our data while providing a portal to facilitate coordination efforts within the small body observer community.MANOS is supported through telescope allocations from NOAO and Lowell Observatory. We acknowledge funding support from an NSF Astronomy and Astrophysics Postdoctoral Fellowship to N. Moskovitz and NASA NEOO grant

  10. Models of the solvent-accessible surface of biopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.E.

    1996-09-01

    Many biopolymers such as proteins, DNA, and RNA have been studied because they have important biomedical roles and may be good targets for therapeutic action in treating diseases. This report describes how plastic models of the solvent-accessible surface of biopolymers were made. Computer files containing sets of triangles were calculated, then used on a stereolithography machine to make the models. Small (2 in.) models were made to test whether the computer calculations were done correctly. Also, files of the type (.stl) required by any ISO 9001 rapid prototyping machine were written onto a CD-ROM for distribution to American companies.

  11. Pediatric vascular access

    International Nuclear Information System (INIS)

    Donaldson, James S.

    2006-01-01

    Pediatric interventional radiologists are ideally suited to provide vascular access services to children because of inherent safety advantages and higher success from using image-guided techniques. The performance of vascular access procedures has become routine at many adult interventional radiology practices, but this service is not as widely developed at pediatric institutions. Although interventional radiologists at some children's hospitals offer full-service vascular access, there is little or none at others. Developing and maintaining a pediatric vascular access service is a challenge. Interventionalists skilled in performing such procedures are limited at pediatric institutions, and institutional support from clerical staff, nursing staff, and technologists might not be sufficiently available to fulfill the needs of such a service. There must also be a strong commitment by all members of the team to support such a demanding service. There is a slippery slope of expected services that becomes steeper and steeper as the vascular access service grows. This review is intended primarily as general education for pediatric radiologists learning vascular access techniques. Additionally, the pediatric or adult interventional radiologist seeking to expand services might find helpful tips. The article also provides education for the diagnostic radiologist who routinely interprets radiographs containing vascular access devices. (orig.)

  12. Anomalous and resonance small-angle scattering

    International Nuclear Information System (INIS)

    Epperson, J.E.; Thiyagarajan, P.

    1988-01-01

    Significant changes in the small-angle scattered intensity can be induced by making measurements with radiation close to an absorption edge of an appropriate atomic species contained in the sample. These changes can be related quantitatively to the real and imaginary anomalous-dispersion terms for the scattering factor (X-rays) or scattering length (neutrons). The physics inherent in these anomalous-dispersion terms is first discussed before consideration of how they enter the relevant scattering theory. Two major areas of anomalous-scattering research have emerged; macromolecules in solution and unmixing of metallic alloys. Research in each area is reviewed, illustrating both the feasibility and potential of these techniques. All the experimental results reported to date have been obtained with X-rays. However, it is pointed out that the formalism is the same for the analog experiment with neutrons, and a number of suitable isotopes exist which exhibit resonance in an accessible range of energy. Potential applications of resonance small-angle neutron scattering are discussed. (orig.)

  13. Implementing a Healthy Food Distribution Program: A Supply Chain Strategy to Increase Fruit and Vegetable Access in Underserved Areas.

    Science.gov (United States)

    DeFosset, Amelia R; Kwan, Allison; Rizik-Baer, Daniel; Gutierrez, Luis; Gase, Lauren N; Kuo, Tony

    2018-05-24

    Increasing access to fresh produce in small retail venues could improve the diet of people in underserved communities. However, small retailers face barriers to stocking fresh produce. In 2014, an innovative distribution program, Community Markets Purchasing Real and Affordable Foods (COMPRA), was launched in Los Angeles with the aim of making it more convenient and profitable for small retailers to stock fresh produce. Our case study describes the key processes and lessons learned in the first 2 years of implementing COMPRA. Considerable investments in staff capacity and infrastructure were needed to launch COMPRA. Early successes included significant week-to-week increases in the volume of produce distributed. Leveraging partnerships, maintaining a flexible operational and funding structure, and broadly addressing store owners' needs contributed to initial gains. We describe key challenges and next steps to scaling the program. Lessons learned from implementing COMPRA could inform other jurisdictions considering supply-side approaches to increase access to healthy food.

  14. Accessibility and use of primary healthcare for immigrants living in the Niagara Region.

    Science.gov (United States)

    Lum, Irene D; Swartz, Rebecca H; Kwan, Matthew Y W

    2016-05-01

    Although the challenges of accessing and using primary healthcare for new immigrants to Canada have been fairly well documented, the focus has primarily been on large cities with significant immigrant populations. The experiences of immigrants living in smaller, less diverse urban centres remain largely unknown. The purpose of this study was to examine the lived experiences of immigrants living in a small urban centre with regards to the primary healthcare system. A total of 13 immigrants living in the Greater Niagara Region participated in semi-structured interviews. All interviews were recorded, transcribed, and then coded and analyzed for emergent themes using NVivo. Five factors were found to impact primary care access and use: lack of social contacts, lack of universal healthcare coverage during their initial arrival, language as a barrier, treatment preferences, and geographic distance to primary care. Overall findings suggest that immigrants moving to smaller areas such as the Niagara Region face similar barriers to primary care as those moving into large cities. Some barriers, however, appear to be specific to the context of smaller urban centres, further exacerbated by living in a small city due to a smaller immigrant population, fewer services for immigrants, and less diversity in practicing physicians. More research is required to understand the contextual factors inhibiting primary care access and use among immigrants moving to smaller urban centres, and determine effective strategies to overcome these barriers. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Working with What We've Got: Perceptions of Barriers and Supports among Small-Metropolitan-Area Same-Sex Adopting Couples

    Science.gov (United States)

    Kinkler, Lori A.; Goldberg, Abbie E.

    2011-01-01

    In seeking to adopt, lesbians and gay men may confront various barriers and obstacles. Ideally, they have access to a variety of support resources that can help to buffer the negative effects of these barriers. Lesbians and gay men living in small metropolitan communities may have limited access to support resources, however. The current…

  16. Food Security and Women's Access to Natural Resources workshop; a brief report.

    Science.gov (United States)

    1997-01-01

    This article describes the workshop on Food Security and Women's Access to Natural Resources, held in January 1997 in Mumbai, India. The workshop was organized jointly by the Tata Institute of Social Sciences and the Indian Association of Women's Studies. The aim was to examine the food security situation in Maharashtra and Gujarat states in the west, the initiative to build alternative institutions, legal changes augmenting industrialization, and how traditional rights to common property resources can be legalized and how the poor can have access to new resources. The workshop organizers were unable to obtain experts on some topics. Core discussion centered on changes in industrialization, natural resources, gender and food security; access to natural resources and poverty alleviation programs; initiatives to create food security; and laws related to access to land and water. Discussions revealed the alienation of small and marginal farmers, landless laborers, and artisans from their livelihoods and survival strategies for these disenfranchised groups. The design of drought eradication and water conservation programs did not permit women and men working at construction sites to have access to the program assets. Case studies revealed situations in which women won the right of access to community water and then negotiated for land in lease. The women used landowners to negotiate credit and access development program assets, but normal channels of the National Bank of Agricultural Research and Development could have provided these benefits. Participants discussed how governments can be held accountable and how public funds could be used to revamp poverty alleviation and asset creation programs. All agreed that macrolevel development should give priority to agricultural development and legal constraints or problems. Five follow-up activities are identified.

  17. 16 CFR 1633.9 - Glossary of terms.

    Science.gov (United States)

    2010-01-01

    ... and stationary (see Figure 11). (m) Futon. A flexible mattress generally used on the floor that can be... riser. This is a frame of sofa seating height with two equal size mattresses without a backrest. The... or two single beds as in a high riser (see Figure 11). (dd) Tufted means buttoned or laced through...

  18. Performance improvement of switched-based interference mitigation for channel assignment in over-loaded small-cell networks

    KAUST Repository

    Gaaloul, Fakhreddine

    2013-05-01

    This paper proposes adequate methods to improve the interference mitigation capability of a recently investigated switched-based interference reduction scheme for single downlink channel assignment in over-loaded small-cell networks. The model assumes that the available orthogonal channels for small cells are distributed among access points in close vicinity, where each access point knows its allocated channels a priori. Each cell has a single antenna, employs the open access strategy, and can reuse its allocated channels simultaneously, while scheduling concurrent service requests. Moreover, the access points can not coordinate their transmissions, and can receive limited feedback from active users. The paper presents low-complexity schemes to identify a suitable channel to serve the scheduled user by maintaining the interference power level within a tolerable range. They attempt to either complement the switched-based scheme by minimum interference channel selection or adopt different interference thresholds on available channels, while reducing the channel examination load. The optimal thresholds for interference mitigation at the desired receive station are quantified for various performance criteria. The performance and processing load of the proposed schemes are obtained analytically, and then compared to those of the single-threshold scheme via numerical and simulation results. © 2002-2012 IEEE.

  19. Does decreased access to emergency departments affect patient outcomes? Analysis of acute myocardial infarction population 1996-2005.

    Science.gov (United States)

    Shen, Yu-Chu; Hsia, Renee Y

    2012-02-01

    We analyze whether decreased emergency department (ED) access results in adverse patient outcomes or changes in the patient health profile for patients with acute myocardial infarction (AMI). We merge Medicare claims, American Hospital Association annual surveys, Medicare hospital cost reports, and location information for 1995-2005. We define four ED access change categories and estimate a ZIP Code fixed-effects regression models on the following AMI outcomes: mortality rates, age, and probability of percutaneous transluminal coronary angioplasty (PTCA) on day of admission. We find a small increase in 30-day to 1-year mortality rates among patients in communities that experience a 30-minute increases, we find a substantial increase in long-term mortality rates, a shift to younger ages (suggesting that older patients die en route), and a higher probability of immediate PTCA. Most of the adverse effects disappear after the transition years. Deterioration in geographic access to ED affects a small segment of the population, and most adverse effects are transitory. Policy planners can minimize the adverse effects by providing assistance to ensure adequate capacity of remaining EDs, and facilitating the realignment of health care resources during the critical transition periods. © Health Research and Educational Trust.

  20. Open access

    African Journals Online (AJOL)

    Prof. Dennis Ocholla

    The argument that access to information is an instrumental and individual as well as ... and Dean School of Information Studies, University of Wisconsin, Milwaukee, USA. ... to scholarly publications and can be in any digital format, including text, movies and ... language barriers, censorship, lack of access to the Internet and ...

  1. Use of small public urban green spaces (SPUGS)

    DEFF Research Database (Denmark)

    Peschardt, Karin Kragsig; Schipperijn, Jasper; Stigsdotter, Ulrika K.

    2012-01-01

    which environmental characteristics users prefer in relation to mental restoration. We investigate nine small public urban green spaces (SPUGS) in the dense city of Copenhagen in order to determine which environmental characteristics may influence the perceived restorativeness of SPUGS amongst average......UGS have been positively associated with stress-related illnesses. Paradoxically the densification tendency in western cities causes decreasing access to green environments. City planners and landscape architects are challenged when designing such areas due to a lack of space and knowledge about...

  2. The trade credit channel revisited : evidence from micro data of Japanese small firms

    NARCIS (Netherlands)

    Ogawa, Kazuo; Sterken, Elmer; Tokutsu, Ichiro

    It is suggested that trade credit can be a substitute for bank loans for small- and medium-sized enterprises (SMEs) that have little access to external funding sources. Using unique cross-sectional survey data of Japanese SMEs, we conduct a deep investigation into the substitutability between bank

  3. Knowledge of disease and access to a specialist reported by Spanish patients with ulcerative colitis: UC-LIFE survey

    Directory of Open Access Journals (Sweden)

    Federico Argüelles-Arias

    Full Text Available Background and aim: Education of patients with ulcerative colitis (UC about their disease and access to a specialist are important to improve health outcomes. Our objective was to determine, by collecting information directly from the patients, their information sources and knowledge of the disease, and the options for access to the gastroenterologist. Methods: The information was collected using a printed survey handed out by 39 gastroenterologists to 15 consecutive adult patients with UC. Patients answered anonymously from their home. The responses were stratified by hospital size (> 900; 500-900; < 500 beds. Results: A total of 585 patients received the survey and 436 responded (74.5%; mean age of 46 years [13.5], 53% men. The main information source was the specialist physician (89.2%. Between 32% and 80% of patients had areas of improvement regarding knowledge of their disease. Knowledge of the disease was better in patients from small hospitals (< 500 beds. The frequency of routine visits was also higher in small hospitals. In case of a flare-up, 60% stated they were able to contact their doctor by phone and 37%, that they could get an appointment on the same day. The percentage stating that they had to ask for an appointment and wait until their physician was available was lower in small hospitals. Conclusions: There are areas of improvement with regard to knowledge of their disease in patients with UC followed in hospital clinics. Patients followed in small hospitals seem to know their disease better, are followed more frequently in the clinic, and have better access in case of a flare-up.

  4. Access 2013 for dummies

    CERN Document Server

    Ulrich Fuller, Laurie

    2013-01-01

    The easy guide to Microsoft Access returns with updates on the latest version! Microsoft Access allows you to store, organize, view, analyze, and share data; the new Access 2013 release enables you to build even more powerful, custom database solutions that integrate with the web and enterprise data sources. Access 2013 For Dummies covers all the new features of the latest version of Accessand serves as an ideal reference, combining the latest Access features with the basics of building usable databases. You'll learn how to create an app from the Welcome screen, get support

  5. Pro Access 2010 Development

    CERN Document Server

    Collins, Mark

    2011-01-01

    Pro Access 2010 Development is a fundamental resource for developing business applications that take advantage of the features of Access 2010 and the many sources of data available to your business. In this book, you'll learn how to build database applications, create Web-based databases, develop macros and Visual Basic for Applications (VBA) tools for Access applications, integrate Access with SharePoint and other business systems, and much more. Using a practical, hands-on approach, this book will take you through all the facets of developing Access-based solutions, such as data modeling, co

  6. Data access performance through parallelization and vectored access. Some results

    International Nuclear Information System (INIS)

    Furano, F; Hanushevsky, A

    2008-01-01

    High Energy Physics data processing and analysis applications typically deal with the problem of accessing and processing data at high speed. Recent studies, development and test work have shown that the latencies due to data access can often be hidden by parallelizing them with the data processing, thus giving the ability to have applications which process remote data with a high level of efficiency. Techniques and algorithms able to reach this result have been implemented in the client side of the Scalla/xrootd system, and in this contribution we describe the results of some tests done in order to compare their performance and characteristics. These techniques, if used together with multiple streams data access, can also be effective in allowing to efficiently and transparently deal with data repositories accessible via a Wide Area Network

  7. Hedging Financial Risks in the Economic Practices of Small Business: Current Imperatives

    Directory of Open Access Journals (Sweden)

    Kolomiyets Ganna M.

    2017-04-01

    Full Text Available The article considers the need to update approaches to hedging the financial risks of small businesses. Reducing the probability of financial costs and losses is of continuing relevance. It appears to be especially critical for small businesses. Small business plays a significant role in the country’s economic system as creator of jobs and as a producer of goods and services that adapts quickly to changing consumer requirements. However, its access to credit resources has certain limitations. The instability of the economic environment by individual factors can affect small businesses not less, and sometimes even more than large and medium-sized businesses. Design of the risk-management in terms of small business needs to be updated. In the current context, there is a need in re-evaluating that the efficient financial risk management can only be carried out in a complex of all the enterprise’s risks, with an increase in the planning horizon and the identification of obstacles to achieving the objective set.

  8. Small-scale soft-bodied robot with multimodal locomotion

    Science.gov (United States)

    Hu, Wenqi; Lum, Guo Zhan; Mastrangeli, Massimo; Sitti, Metin

    2018-02-01

    Untethered small-scale (from several millimetres down to a few micrometres in all dimensions) robots that can non-invasively access confined, enclosed spaces may enable applications in microfactories such as the construction of tissue scaffolds by robotic assembly, in bioengineering such as single-cell manipulation and biosensing, and in healthcare such as targeted drug delivery and minimally invasive surgery. Existing small-scale robots, however, have very limited mobility because they are unable to negotiate obstacles and changes in texture or material in unstructured environments. Of these small-scale robots, soft robots have greater potential to realize high mobility via multimodal locomotion, because such machines have higher degrees of freedom than their rigid counterparts. Here we demonstrate magneto-elastic soft millimetre-scale robots that can swim inside and on the surface of liquids, climb liquid menisci, roll and walk on solid surfaces, jump over obstacles, and crawl within narrow tunnels. These robots can transit reversibly between different liquid and solid terrains, as well as switch between locomotive modes. They can additionally execute pick-and-place and cargo-release tasks. We also present theoretical models to explain how the robots move. Like the large-scale robots that can be used to study locomotion, these soft small-scale robots could be used to study soft-bodied locomotion produced by small organisms.

  9. Open Access

    Science.gov (United States)

    Suber, Peter

    2012-01-01

    The Internet lets us share perfect copies of our work with a worldwide audience at virtually no cost. We take advantage of this revolutionary opportunity when we make our work "open access": digital, online, free of charge, and free of most copyright and licensing restrictions. Open access is made possible by the Internet and copyright-holder…

  10. News from the Library: Scientific American and Nature increasingly accessible online!

    CERN Multimedia

    CERN Library

    2011-01-01

    Since a few weeks, the CERN Library has been offering online access to "Scientific American" and "Nature" within a longer timespan. This is part of a long-term plan to extend our e-collections in order to include prestigious scientific journals from the beginning of publication.   CERN users can browse and read the complete archives of "Scientific American" since 1845. Among the many interesting articles now readable online, you can find Einstein's account of research on a generalized theory of gravitation. A small, though important addition to the Library's online collections: "Nature" online is now reaching back to 1987. You can now read online the "Nature" news column reporting about the first anti-atom discovered at CERN. We plan to further expand online access to "Nature", but in the meantime you can rely on the Library's paper collection...

  11. News from the Library: Scientific American and Nature increasingly accessible online!

    CERN Multimedia

    CERN Library

    2012-01-01

    Since a few weeks, the CERN Library has been offering online access to "Scientific American" and "Nature" within a longer timespan. This is part of a long-term plan to extend our e-collections in order to include prestigious scientific journals from the beginning of publication.   CERN users can browse and read the complete archives of "Scientific American" since 1845. Among the many interesting articles now readable online, you can find Einstein's account of research on a generalized theory of gravitation. A small, though important addition to the Library's online collections: "Nature" online is now reaching back to 1987. You can now read online the "Nature" news column reporting about the first anti-atom discovered at CERN. We plan to further expand online access to "Nature", but in the meantime you can rely on the Library's paper collection...

  12. Impacts of ungulates on the demography and diversity of small mammals in central Kenya.

    Science.gov (United States)

    Keesing, Felicia

    1998-09-01

    The impacts of ungulates on small mammals in an East African savanna habitat were investigated by monitoring the population and community responses of small mammals on replicated 4-ha plots from which ungulates had been excluded. The dominant small mammal in this habitat is the pouched mouse, Saccostomusmearnsi, a medium-sized murid rodent. Eight other small mammal species, including Arvicanthis sp., Mus sp., Mastomys sp., Dendromus sp., Crocidura sp., and, rarely, Tatera sp., Aethomys sp., and Acomys sp., were also captured. The dominant ungulates are elephant (Loxodonta africana), giraffe (Giraffa camelopardalis), Grevy's and common zebra (Equus grevyi and E. burchelli), buffalo (Syncerus cafer), eland (Taurotragus oryx), Grant's gazelle (Gazella granti), and domestic cattle. Within 1 year, S. mearnsi populations had responded dramatically to the exclusion of large mammals by a two-fold increase in density, a difference that was maintained through pronounced seasonal fluctuations in the second year. Though individual pouched mice showed no significant differences in their use of space with and without ungulates, male S. mearnsi maintained significantly higher body weights in the absence of ungulates, indicating that habitat quality had increased. One other species, Mastomys sp., also increased in the absence of ungulates. Overall, the small mammal community maintained relatively constant species diversity on the plots to which ungulates did not have access. On the plots to which ungulates did have access, on the other hand, there was a rapid 75% decrease in diversity in the control plots during one trapping session. Ungulates are most likely affecting small mammals through their effects on food quality, since there were no detectable differences in their exposure to predators, as determined by vegetative cover, in the absence of ungulates. These results demonstrate that ungulates can have strong and rapid impacts on small mammal abundance and diversity in East

  13. Toward reliable estimates of seed removal by small mammals and birds in the Neotropics

    Directory of Open Access Journals (Sweden)

    AV. Christianini

    Full Text Available Birds are often considered seed predators of less importance when compared to rodents or granivorous ants in studies of seed predation using selective exclosures. However, it is possible that the role of granivorous birds interacting with seeds on the floor of Neotropical forests is being underestimated, if the selective exclosures designed to allow exclusive access to small rodents do not work properly in the Neotropics. We used an experimental approach to evaluate whether birds could remove seeds from selective exclosures designed to allow exclusive access to rodents. We compared seed removal from two paired treatments in the field: an open treatment (control allowing the access to all vertebrates, and a selective exclosure treatment, where seeds were placed under a cage staked to the ground and covered on top and on the laterals by wire mesh of varying sizes. Treatments were placed in the center of a sand quadrat in order to record the visit of vertebrates from their footprints. Although the selective exclosures are used to tell apart the small mammal seed removal from that of other animals, birds could persistently remove seeds from selective exclosures. Thus, the role of birds interacting with seeds on the floor of tropical forests may be underestimated for some plant species, due to an artifact of the exclosure method employed. Exclosures of 40 x 40 x 40 cm should be efficient to deter the removal of seeds by birds, allowing the consumption of the seeds by small mammals at the same time.

  14. Migrants' access to healthcare

    DEFF Research Database (Denmark)

    Norredam, Marie

    2011-01-01

    There are strong pragmatic and moral reasons for receiving societies to address access to healthcare for migrants. Receiving societies have a pragmatic interest in sustaining migrants' health to facilitate integration; they also have a moral obligation to ensure migrants' access to healthcare...... according to international human rights principles. The intention of this thesis is to increase the understanding of migrants' access to healthcare by exploring two study aims: 1) Are there differences in migrants' access to healthcare compared to that of non-migrants? (substudy I and II); and 2) Why...... are there possible differences in migrants' access to healthcare compared to that of non-migrants? (substudy III and IV). The thesis builds on different methodological approaches using both register-based retrospective cohort design, cross-sectional design and survey methods. Two different measures of access were...

  15. Measuring depth in boreholes

    International Nuclear Information System (INIS)

    Hodson, G.M.

    1979-01-01

    This invention relates to a method of determining the depth of rock strata and other features of a borehole. It may be employed with particular advantage when access to the top of the borehole is difficult, for example in underwater operations. A radioactive marker, such as a source of gamma rays, is positioned near the top of the riser of a sub-sea wellhead structure. A radiation detector is lowered between the marker and a radioactive stratum and the length of line supplied is measured on the floating platform. This enables the depth of the stratum to be measured irrespective of tidal variations of the height of the platform. (U.K.)

  16. Association of State Access Standards With Accessibility to Specialists for Medicaid Managed Care Enrollees.

    Science.gov (United States)

    Ndumele, Chima D; Cohen, Michael S; Cleary, Paul D

    2017-10-01

    Medicaid recipients have consistently reported less timely access to specialists than patients with other types of coverage. By 2018, state Medicaid agencies will be required by the Center for Medicare and Medicaid Services (CMS) to enact time and distance standards for managed care organizations to ensure an adequate supply of specialist physicians for enrollees; however, there have been no published studies of whether these policies have significant effects on access to specialty care. To compare ratings of access to specialists for adult Medicaid and commercial enrollees before and after the implementation of specialty access standards. We used Consumer Assessment of Healthcare Providers and Systems survey data to conduct a quasiexperimental difference-in-differences (DID) analysis of 20 163 nonelderly adult Medicaid managed care (MMC) enrollees and 54 465 commercially insured enrollees in 5 states adopting access standards, and 37 290 MMC enrollees in 5 matched states that previously adopted access standards. Reported access to specialty care in the previous 6 months. Seven thousand six hundred ninety-eight (69%) Medicaid enrollees and 28 423 (75%) commercial enrollees reported that it was always or usually easy to get an appointment with a specialist before the policy implementation (or at baseline) compared with 11 889 (67%) of Medicaid enrollees in states that had previously implemented access standards. Overall, there was no significant improvement in timely access to specialty services for MMC enrollees in the period following implementation of standard(s) (adjusted difference-in-differences, -1.2 percentage points; 95% CI, -2.7 to 0.1), nor was there any impact of access standards on insurance-based disparities in access (0.6 percentage points; 95% CI, -4.3 to 5.4). There was heterogeneity across states, with 1 state that implemented both time and distance standards demonstrating significant improvements in access and reductions in disparities

  17. Fishing Access Areas

    Data.gov (United States)

    Vermont Center for Geographic Information — The Vermont Fish & Wildlife Department maintains developed fishing access areas. These sites provide public access to waters in Vermont for shore fishing...

  18. Potential Beneficiaries Of Cloud Accounting Technology: Small Or Large Companies?

    Directory of Open Access Journals (Sweden)

    Bogdan Ştefan Ionescu

    2013-05-01

    Full Text Available The article addresses the issue of Cloud Computing concept from the perspective of its implications on the business environment. In this respect we have analyzed the changes brought by the new technology which come to connect the discontinuities between the IT solutions adopted by small and medium organizations and those adopted by large corporations. The article analyzes the benefits and limitations of cloud both in terms of small companies and in terms of more developed entities. Whatever the size and type of organization but especially for SMEs Cloud provides a competitive advantage by providing access to affordable, reliable and flexible IT solutions that allows them to operate more efficiently among their competitors in the market.

  19. Unlocking the Gates: How and Why Leading Universities Are Opening up Access to Their Courses

    Science.gov (United States)

    Walsh, Taylor

    2011-01-01

    Over the past decade, a small revolution has taken place at some of the world's leading universities, as they have started to provide free access to undergraduate course materials--including syllabi, assignments, and lectures--to anyone with an Internet connection. Yale offers high-quality audio and video recordings of a careful selection of…

  20. Development of a statistically based access delay timeline methodology.

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, W. Gary; Robinson, David Gerald; Wyss, Gregory Dane; Hendrickson, Stacey M. Langfitt

    2013-02-01

    The charter for adversarial delay is to hinder access to critical resources through the use of physical systems increasing an adversarys task time. The traditional method for characterizing access delay has been a simple model focused on accumulating times required to complete each task with little regard to uncertainty, complexity, or decreased efficiency associated with multiple sequential tasks or stress. The delay associated with any given barrier or path is further discounted to worst-case, and often unrealistic, times based on a high-level adversary, resulting in a highly conservative calculation of total delay. This leads to delay systems that require significant funding and personnel resources in order to defend against the assumed threat, which for many sites and applications becomes cost prohibitive. A new methodology has been developed that considers the uncertainties inherent in the problem to develop a realistic timeline distribution for a given adversary path. This new methodology incorporates advanced Bayesian statistical theory and methodologies, taking into account small sample size, expert judgment, human factors and threat uncertainty. The result is an algorithm that can calculate a probability distribution function of delay times directly related to system risk. Through further analysis, the access delay analyst or end user can use the results in making informed decisions while weighing benefits against risks, ultimately resulting in greater system effectiveness with lower cost.

  1. Web Accessibility and Guidelines

    Science.gov (United States)

    Harper, Simon; Yesilada, Yeliz

    Access to, and movement around, complex online environments, of which the World Wide Web (Web) is the most popular example, has long been considered an important and major issue in the Web design and usability field. The commonly used slang phrase ‘surfing the Web’ implies rapid and free access, pointing to its importance among designers and users alike. It has also been long established that this potentially complex and difficult access is further complicated, and becomes neither rapid nor free, if the user is disabled. There are millions of people who have disabilities that affect their use of the Web. Web accessibility aims to help these people to perceive, understand, navigate, and interact with, as well as contribute to, the Web, and thereby the society in general. This accessibility is, in part, facilitated by the Web Content Accessibility Guidelines (WCAG) currently moving from version one to two. These guidelines are intended to encourage designers to make sure their sites conform to specifications, and in that conformance enable the assistive technologies of disabled users to better interact with the page content. In this way, it was hoped that accessibility could be supported. While this is in part true, guidelines do not solve all problems and the new WCAG version two guidelines are surrounded by controversy and intrigue. This chapter aims to establish the published literature related to Web accessibility and Web accessibility guidelines, and discuss limitations of the current guidelines and future directions.

  2. Android Access Control Extension

    Directory of Open Access Journals (Sweden)

    Anton Baláž

    2015-12-01

    Full Text Available The main objective of this work is to analyze and extend security model of mobile devices running on Android OS. Provided security extension is a Linux kernel security module that allows the system administrator to restrict program's capabilities with per-program profiles. Profiles can allow capabilities like network access, raw socket access, and the permission to read, write, or execute files on matching paths. Module supplements the traditional Android capability access control model by providing mandatory access control (MAC based on path. This extension increases security of access to system objects in a device and allows creating security sandboxes per application.

  3. A question of choice? Access to energy solutions in Ethiopia, Kenya and Uganda

    International Nuclear Information System (INIS)

    Doyle, Jeremy

    2002-01-01

    It is well known that in rural and peri-urban areas of many developing countries, a primary source of fuel is biomass (wood and charcoal) and that access to the electricity grid is very limited. However, potential for people to select and purchase other energy products that offer improved energy services, like kerosene, batteries, wind generators, solar PV, LPG and small generators is much less understood. (Author)

  4. A question of choice? Access to energy solutions in Ethiopia, Kenya and Uganda

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, Jeremy [Energy for Sustainable Development (ESD), International Div., Neston, Corsham (United Kingdom)

    2002-06-01

    It is well known that in rural and peri-urban areas of many developing countries, a primary source of fuel is biomass (wood and charcoal) and that access to the electricity grid is very limited. However, potential for people to select and purchase other energy products that offer improved energy services, like kerosene, batteries, wind generators, solar PV, LPG and small generators is much less understood. (Author)

  5. A cross-sectional ecological study of spatial scale and geographic inequality in access to drinking-water and sanitation.

    Science.gov (United States)

    Yu, Weiyu; Bain, Robert E S; Mansour, Shawky; Wright, Jim A

    2014-11-26

    Measuring inequality in access to safe drinking-water and sanitation is proposed as a component of international monitoring following the expiry of the Millennium Development Goals. This study aims to evaluate the utility of census data in measuring geographic inequality in access to drinking-water and sanitation. Spatially referenced census data were acquired for Colombia, South Africa, Egypt, and Uganda, whilst non-spatially referenced census data were acquired for Kenya. Four variants of the dissimilarity index were used to estimate geographic inequality in access to both services using large and small area units in each country through a cross-sectional, ecological study. Inequality was greatest for piped water in South Africa in 2001 (based on 53 areas (N) with a median population (MP) of 657,015; D = 0.5599) and lowest for access to an improved water source in Uganda in 2008 (N = 56; MP = 419,399; D = 0.2801). For sanitation, inequality was greatest for those lacking any facility in Kenya in 2009 (N = 158; MP = 216,992; D = 0.6981), and lowest for access to an improved facility in Uganda in 2002 (N = 56; MP = 341,954; D = 0.3403). Although dissimilarity index values were greater for smaller areal units, when study countries were ranked in terms of inequality, these ranks remained unaffected by the choice of large or small areal units. International comparability was limited due to definitional and temporal differences between censuses. This five-country study suggests that patterns of inequality for broad regional units do often reflect inequality in service access at a more local scale. This implies household surveys designed to estimate province-level service coverage can provide valuable insights into geographic inequality at lower levels. In comparison with household surveys, censuses facilitate inequality assessment at different spatial scales, but pose challenges in harmonising water and sanitation typologies across countries.

  6. Strategic Accessibility Competition

    OpenAIRE

    Bacchiega, Emanuele; Randon, Emanuela; Zirulia, Lorenzo

    2010-01-01

    We analyze the effect of competition in market-accessibility enhancement among quality-differentiated firms. Firms are located in regions with different ex-ante transport costs to reach the final market. We characterize the equilibrium of the two-stage game in which firms first invest to improve market accessibility and then compete in prices. Efforts in accessibility improvement crucially depend on the interplay between the willingness to pay for the quality premium of the median consumer an...

  7. On the Potential of Full Duplex Communication in 5G Small Cell Networks

    DEFF Research Database (Denmark)

    Mahmood, Nurul Huda; Berardinelli, Gilberto; Tavares, Fernando Menezes Leitão

    2015-01-01

    , the potential throughput gain may not be 100% as promised. In this study, we evaluate the performance of full duplex communication in a dense small cell scenario as targeted by future 5th Generation (5G) radio access technology under the ideal assumptions of a full buffer, always active traffic model...

  8. Performance analysis of quantum access network using code division multiple access model

    International Nuclear Information System (INIS)

    Hu Linxi; Yang Can; He Guangqiang

    2017-01-01

    A quantum access network has been implemented by frequency division multiple access and time division multiple access, while code division multiple access is limited for its difficulty to realize the orthogonality of the code. Recently, the chaotic phase shifters were proposed to guarantee the orthogonality by different chaotic signals and spread the spectral content of the quantum states. In this letter, we propose to implement the code division multiple access quantum network by using chaotic phase shifters and synchronization. Due to the orthogonality of the different chaotic phase shifter, every pair of users can faithfully transmit quantum information through a common channel and have little crosstalk between different users. Meanwhile, the broadband spectra of chaotic signals efficiently help the quantum states to defend against channel loss and noise. (paper)

  9. Testing a small UAS for mapping artisanal diamond mining sites in Africa

    Science.gov (United States)

    Malpeli, Katherine C.; Chirico, Peter G.

    2015-01-01

    Remote sensing technology is advancing at an unprecedented rate. At the forefront of the new technological developments are unmanned aircraft systems (UAS). The advent of small, lightweight, low-cost, and user-friendly UAS is greatly expanding the potential applications of remote sensing technology and improving the set of tools available to researchers seeking to map and monitor terrain from above. In this article, we explore the applications of a small UAS for mapping informal diamond mining sites in Africa. We found that this technology provides aerial imagery of unparalleled resolution in a data-sparse, difficult to access, and remote terrain.

  10. Design for Accessibility

    DEFF Research Database (Denmark)

    Herriott, Richard

    2012-01-01

    A report on how nine rail builder, operators and transport designers deal with design for accessibility......A report on how nine rail builder, operators and transport designers deal with design for accessibility...

  11. Small area estimation of proportions with different levels of auxiliary data.

    Science.gov (United States)

    Chandra, Hukum; Kumar, Sushil; Aditya, Kaustav

    2018-03-01

    Binary data are often of interest in many small areas of applications. The use of standard small area estimation methods based on linear mixed models becomes problematic for such data. An empirical plug-in predictor (EPP) under a unit-level generalized linear mixed model with logit link function is often used for the estimation of a small area proportion. However, this EPP requires the availability of unit-level population information for auxiliary data that may not be always accessible. As a consequence, in many practical situations, this EPP approach cannot be applied. Based on the level of auxiliary information available, different small area predictors for estimation of proportions are proposed. Analytic and bootstrap approaches to estimating the mean squared error of the proposed small area predictors are also developed. Monte Carlo simulations based on both simulated and real data show that the proposed small area predictors work well for generating the small area estimates of proportions and represent a practical alternative to the above approach. The developed predictor is applied to generate estimates of the proportions of indebted farm households at district-level using debt investment survey data from India. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Regulation of Small and Medium-Sized Business Development in Russia: Problems and Solutions

    Directory of Open Access Journals (Sweden)

    Lyudmila Yuryevna Bogachkova

    2015-12-01

    Full Text Available The authors prove that despite the active state policy carried out since the second half of the 2000s and aimed at supporting small and medium-sized business in the Russian Federation, the current level of development of this economic sector is insufficient. The present paper characterizes the modern structure of small and medium-sized business. The authors show that the main problems hindering its growth are conditioned by low market demand, large tax deductions, numerous administrative barriers, lack of funding and state support. On the basis of the official data of Russian Federal State Statistics Service on theresults of annual surveys of entrepreneurs, the authors revealed the factors that prevented innovation situation in the country have stable negative impact on MSB, while the impact of such factors as imperfect legal and regulatory framework, investment risks, low profitability and inadequate state of technological infrastructure is relatively nonsignificant. The authors describe systemwide and resource measures of state regulation of small and medium-sized business. The system-wide measures include preferential access to production facilities and equipment, special tax regimes, administrative control. The measures of resource support to entrepreneurs consist in subsidizing the lease payments and interest rates on loans for the modernization of production; grant support, the establishment of microfinance organizations and guarantee funds, the development of business support infrastructure. The authors describe the forms of these measures implementation in 2013 and the main directions of improving the state regulation of small and medium-sized business, including the reduction of tax burden and facilitation of taxation procedures, the reduction of administrative barriers and ensuring access of small and medium-sized enterprises to government orders and technological infrastructure.

  13. The application of small-angle neutron scattering to the study of mass transfer in clays

    International Nuclear Information System (INIS)

    Allen, A.J.; Baston, A.H.; Bourke, P.J.; Jefferies, N.L.

    1990-01-01

    An extensive study using small angle neutron scattering (SANS) has been made of the pore structures in London Clay and in Ca-montmorillonite. Using SANS contrast variation techniques, the accessibilities of the pores to D 2 O by diffusion and permeation have been studied. Characterisation of the accessibility to different parts of the pore structure is intended to provide input data for models of radionuclide transport through clay geological barriers, and to improve interpretation of laboratory experiments that measure sorption of radionuclides on clays. (author)

  14. Atomic memory access hardware implementations

    Science.gov (United States)

    Ahn, Jung Ho; Erez, Mattan; Dally, William J

    2015-02-17

    Atomic memory access requests are handled using a variety of systems and methods. According to one example method, a data-processing circuit having an address-request generator that issues requests to a common memory implements a method of processing the requests using a memory-access intervention circuit coupled between the generator and the common memory. The method identifies a current atomic-memory access request from a plurality of memory access requests. A data set is stored that corresponds to the current atomic-memory access request in a data storage circuit within the intervention circuit. It is determined whether the current atomic-memory access request corresponds to at least one previously-stored atomic-memory access request. In response to determining correspondence, the current request is implemented by retrieving data from the common memory. The data is modified in response to the current request and at least one other access request in the memory-access intervention circuit.

  15. Vascular access in pediatric patients in the emergency department: types of access, indications, and complications [digest].

    Science.gov (United States)

    Whitney, Rachel; Langhan, Melissa; Pade, Kathryn H

    2017-06-22

    Vascular access is a potentially life-saving procedure that is a mainstay of emergency medicine practice. There are a number of challenges associated with obtaining and maintaining vascular access, and the choice of the route of access and equipment used will depend on patient- and provider-specific factors. In this issue, the indications and complications of peripheral intravenous access, intraosseous access, and central venous access are reviewed. Timely and effective assessment and management of difficult-access patients, pain control techniques that can assist vascular access, and contraindications to each type of vascular access are also discussed. [Points & Pearls is a digest of Pediatric Emergency Medicine Practice].

  16. Tank vapor characterization project - Tank 241-U-112 headspace gas and vapor characterization: Results for homogeneity samples collected on December 6, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Sklarew, D.S.; Pool, K.H.; Evans, J.C.; Hayes, J.C. [and others

    1997-09-01

    This report presents the results of analyses of samples taken from the headspace of waste storage tank 241-U-112 (Tank U-112) at the Hanford Site in Washington State. Samples were collected to determine the homogeneity of selected inorganic and organic headspace constitutents. Two risers (Riser 3 and Riser 6) were sampled at three different elevations (Bottom, Middle, and Top) within the tank. Tank headspace samples were collected by SGN Eurisys Service Corporation (SESC) and were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Ammonia was determined to be above the immediate notification limit specified by the sampling and analysis plan.

  17. Forbidden Access

    CERN Multimedia

    C. Colloca TS/FM

    2004-01-01

    TS/FM group informs you that, for the replacement of the door of the main entrance at bldg. 500, the access will be closed to the public between 19 and 30 July 2004. Access to the Main Building complex will be assured at any time through both of the side doors and from bldg. 64. For more information, please contact 73273. C. Colloca TS/FM

  18. A remark on accessibility

    International Nuclear Information System (INIS)

    Wu, Xinxing; Wang, Jianjun

    2016-01-01

    Highlights: • Obtain some characteristics of accessibility and Kato’s chaos. • Answer negatively a question in [Li R, Wang H, Zhao Y. Kato’s chaos in duopoly games. Chaos Solit Fract 2016;84:69–72]. • A dynamical system is indecomposable if and only if it is weakly transitive. - Abstract: This note obtains some characteristics of accessibility and Kato’s chaos. Applying these results, an accessible dynamical system whose product system is not accessible is constructed, giving a negative answer to a question in [Li R, Wang H, Zhao Y. Kato’s chaos in duopoly games. Chaos Solit Fract 2016;84:69–72]. Besides, it is proved that every transitive interval self-map is accessible.

  19. Accessibility observations of visually impaired users using the South African National Accessibility Portal

    CSIR Research Space (South Africa)

    Coetzee, L

    2008-05-01

    Full Text Available . Improving web site accessibility has proven to be a challenging task with a myriad of standards, accessibility testing tools and few technical guides for implementation. This paper presents the South African National Accessibility Portal (NAP), which is used...

  20. Basic principles of dental office logistics: organizing dental supplies and equipment for optimal accessibility.

    Science.gov (United States)

    Mamoun, John

    2012-01-01

    To maximize office production, dentists should continuously perform treatment-related tasks throughout the workday. To this end, the office should logically organize and store dental instruments, disposables, materials, handpieces, and small equipment to optimize accessibility of these items at the moment when the dentist needs them. The office needs multiple copies of these items to prevent their inaccessibility during the workday due to breakdown, inventory depletion, or lack of a sterilized copy of the item when needed. Staff should know where all items are located in the office at all times to minimize the time needed to search for them. This article describes how to organize dental items in an office for optimal accessibility to the dentist during procedures.