Science.gov

Sample records for hydraulic design features

  1. Design of hydraulic recuperation unit

    NASA Astrophysics Data System (ADS)

    Jandourek, Pavel; Habán, Vladimír; Hudec, Martin; Dobšáková, Lenka; Štefan, David

    2016-03-01

    This article deals with design and measurement of hydraulic recuperation unit. Recuperation unit consist of radial turbine and axial pump, which are coupled on the same shaft. Speed of shaft with impellers are 6000 1/min. For economic reasons, is design of recuperation unit performed using commercially manufactured propellers.

  2. Design of hydraulic output Stirling engine

    NASA Technical Reports Server (NTRS)

    Toscano, W. M.; Harvey, A. C.; Lee, K.

    1983-01-01

    A hydraulic output system for the RE-1000 free piston stirling engine (FPSE) was designed. The hydraulic output system can be readily integrated with the existing hot section of RE-1000 FPSE. The system has two simply supported diaphragms which separate the engine gas from the hydraulic fluid, a dynamic balance mechanism, and a novel, null center band hydraulic pump. The diaphragms are designed to endure more than 10 billion cycles, and to withstand the differential pressure load as high as 14 MPa. The projected thermodynamic performance of the hydraulic output version of RE-1000 FPSE is 1.87 kW at 29/7 percent brake efficiency.

  3. Hydraulic design development of Xiluodu Francis turbine

    NASA Astrophysics Data System (ADS)

    Wang, Y. L.; Li, G. Y.; Shi, Q. H.; Wang, Z. N.

    2012-11-01

    Hydraulic optimization design with CFD (Computational Fluid Dynamics) method, hydraulic optimization measures and model test results in the hydraulic development of Xiluodu hydropower station by DFEM (Dongfang Electric Machinery) of DEC (Dongfang Electric Corporation) of China were analyzed in this paper. The hydraulic development conditions of turbine, selection of design parameter, comparison of geometric parameters and optimization measure of turbine flow components were expatiated. And the measures of improving turbine hydraulic performance and the results of model turbine acceptance experiment were discussed in details.

  4. Hydraulically powered dissimilar teleoperated system controller design

    SciTech Connect

    Jansen, J.F.; Kress, R.L.

    1996-04-01

    This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented.

  5. Issues of a Computer-Aided Design of Hydraulic Jacks

    NASA Astrophysics Data System (ADS)

    Averchenkov, V. I.; Averchenkov, A. V.; Kolyakinand, V. V.; Orekhov, O. D.

    2016-04-01

    The article deals with the issues of a computer-aided design of hydraulic equipment, namely hydraulic jacks. Design principles of the hydraulic jack CAD system are described. In addition, the possibilities for the system improvement and expansion are considered.

  6. Escalator design features evaluation

    NASA Technical Reports Server (NTRS)

    Zimmerman, W. F.; Deshpande, G. K.

    1982-01-01

    Escalators are available with design features such as dual speed (90 and 120 fpm), mat operation and flat steps. These design features were evaluated based on the impact of each on capital and operating costs, traffic flow, and safety. A human factors engineering model was developed to analyze the need for flat steps at various speeds. Mat operation of escalators was found to be cost effective in terms of energy savings. Dual speed operation of escalators with the higher speed used during peak hours allows for efficient operation. A minimum number of flat steps required as a function of escalator speed was developed to ensure safety for the elderly.

  7. Digital hydraulic valving system. [design and development

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The design and development are reported of a digital hydraulic valving system that would accept direct digital inputs. Topics include: summary of contractual accomplishments, design and function description, valve parameters and calculations, conclusions, and recommendations. The electrical control circuit operating procedure is outlined in an appendix.

  8. Hydraulics.

    ERIC Educational Resources Information Center

    Decker, Robert L.

    Designed for use in courses where students are expected to become proficient in the area of hydraulics, including diesel engine mechanic programs, this curriculum guide is comprised of fourteen units of instruction. Unit titles include (1) Introduction, (2) Fundamentals of Hydraulics, (3) Reservoirs, (4) Lines, Fittings, and Couplers, (5) Seals,…

  9. Hydraulic design of pervious concrete highway shoulders

    NASA Astrophysics Data System (ADS)

    Grahl, Nathan Andrew

    Stormwater drainage has been a factor in roadway design for years. Now stormwater quantity and quality are also becoming regulated for roadways. As regulations of stormwater management continue to increase so does the need for more viable and effect management practices. The research presented and discussed in this thesis presents the option of using pervious concrete in highway shoulders as a best management practice for stormwater management. Research focused on the hydraulic response of pervious concrete pavements exposed to sheet flowing water. Pervious concrete samples were placed in a hydraulic flume to determine capture discharges, infiltration rates, and by-pass flowrates for a broad range of void contents, across a broad range of pavement cross slopes. The results demonstrate that the capture discharge and infiltration rates are inversely related to the cross slope of the pavement. Results also showed the infiltration rate of the permeable pavement exposed to sheet flowing water, in the model, is significantly lower than the measured infiltration rate. Pervious concrete samples were also tested to determine hydraulic response when exposed to clogging associated with sand used in roadway de-icing. The results of the clogging of the permeable pavements followed similar trends as the unclogged samples, with the only difference being a more significant reduction in infiltration rates at higher applications of sand. Preliminary discussion of a design methodology is included with a design example.

  10. Reliability design for impact vibration of hydraulic pressure pipeline systems

    NASA Astrophysics Data System (ADS)

    Zhang, Tianxiao; Liu, Xinhui

    2013-09-01

    The research of reliability design for impact vibration of hydraulic pressure pipeline systems is still in the primary stage, and the research of quantitative reliability of hydraulic components and system is still incomplete. On the condition of having obtained the numerical characteristics of basic random parameters, several techniques and methods including the probability statistical theory, hydraulic technique and stochastic perturbation method are employed to carry out the reliability design for impact vibration of the hydraulic pressure system. Considering the instantaneous pressure pulse of hydraulic impact in pipeline, the reliability analysis model of hydraulic pipeline system is established, and the reliability-based optimization design method is presented. The proposed method can reflect the inherent reliability of hydraulic pipe system exactly, and the desired result is obtained. The reliability design of hydraulic pipeline system is achieved by computer programs and the reliability design information of hydraulic pipeline system is obtained. This research proposes a reliability design method, which can solve the problem of the reliability-based optimization design for the hydraulic pressure system with impact vibration practically and effectively, and enhance the quantitative research on the reliability design of hydraulic pipeline system. The proposed method has generality for the reliability optimization design of hydraulic pipeline system.

  11. Development of a hydraulic turbine design method

    NASA Astrophysics Data System (ADS)

    Kassanos, Ioannis; Anagnostopoulos, John; Papantonis, Dimitris

    2013-10-01

    In this paper a hydraulic turbine parametric design method is presented which is based on the combination of traditional methods and parametric surface modeling techniques. The blade of the turbine runner is described using Bezier surfaces for the definition of the meridional plane as well as the blade angle distribution, and a thickness distribution applied normal to the mean blade surface. In this way, it is possible to define parametrically the whole runner using a relatively small number of design parameters, compared to conventional methods. The above definition is then combined with a commercial CFD software and a stochastic optimization algorithm towards the development of an automated design optimization procedure. The process is demonstrated with the design of a Francis turbine runner.

  12. CFD Aided Design and Production of Hydraulic Turbines

    NASA Astrophysics Data System (ADS)

    Kaplan, Alper; Cetinturk, Huseyin; Demirel, Gizem; Ayli, Ece; Celebioglu, Kutay; Aradag, Selin; ETU Hydro Research Center Team

    2014-11-01

    Hydraulic turbines are turbo machines which produce electricity from hydraulic energy. Francis type turbines are the most common one in use today. The design of these turbines requires high engineering effort since each turbine is tailor made due to different head and discharge. Therefore each component of the turbine is designed specifically. During the last decades, Computational Fluid Dynamics (CFD) has become very useful tool to predict hydraulic machinery performance and save time and money for designers. This paper describes a design methodology to optimize a Francis turbine by integrating theoretical and experimental fundamentals of hydraulic machines and commercial CFD codes. Specific turbines are designed and manufactured with the help of a collaborative CFD/CAD/CAM methodology based on computational fluid dynamics and five-axis machining for hydraulic electric power plants. The details are presented in this study. This study is financially supported by Turkish Ministry of Development.

  13. CFD based draft tube hydraulic design optimization

    NASA Astrophysics Data System (ADS)

    McNabb, J.; Devals, C.; Kyriacou, S. A.; Murry, N.; Mullins, B. F.

    2014-03-01

    The draft tube design of a hydraulic turbine, particularly in low to medium head applications, plays an important role in determining the efficiency and power characteristics of the overall machine, since an important proportion of the available energy, being in kinetic form leaving the runner, needs to be recovered by the draft tube into static head. For large units, these efficiency and power characteristics can equate to large sums of money when considering the anticipated selling price of the energy produced over the machine's life-cycle. This same draft tube design is also a key factor in determining the overall civil costs of the powerhouse, primarily in excavation and concreting, which can amount to similar orders of magnitude as the price of the energy produced. Therefore, there is a need to find the optimum compromise between these two conflicting requirements. In this paper, an elaborate approach is described for dealing with this optimization problem. First, the draft tube's detailed geometry is defined as a function of a comprehensive set of design parameters (about 20 of which a subset is allowed to vary during the optimization process) and are then used in a non-uniform rational B-spline based geometric modeller to fully define the wetted surfaces geometry. Since the performance of the draft tube is largely governed by 3D viscous effects, such as boundary layer separation from the walls and swirling flow characteristics, which in turn governs the portion of the available kinetic energy which will be converted into pressure, a full 3D meshing and Navier-Stokes analysis is performed for each design. What makes this even more challenging is the fact that the inlet velocity distribution to the draft tube is governed by the runner at each of the various operating conditions that are of interest for the exploitation of the powerhouse. In order to determine these inlet conditions, a combined steady-state runner and an initial draft tube analysis, using a

  14. The design and evaluation of a hydraulic actuation system for a legged rough-terrain vehicle

    NASA Astrophysics Data System (ADS)

    Srinivasan, K.; Waldron, K. J.; Dworak, J. A.

    One of the causes of low efficiency of legged vehicles is the type of actuation system used. This paper describes the overall design and the evaluation of some aspects of a proposed hydraulic actuation system for a six-legged vehicle intended for use in rough terrain. Features of the hydraulic actuation system designed to improve mechanical efficiency are described. A combination of linearized dynamic system analysis and computer simulation of the nonlinear dynamic system equations is used to evaluate some aspects of the proposed design. The tradeoff between energy efficient operation and the dynamic performance of the actuation system is investigated. Some criteria for controller design are enumerated.

  15. Hydraulics.

    ERIC Educational Resources Information Center

    Decker, Robert L.; Kirby, Klane

    This curriculum guide contains a course in hydraulics to train entry-level workers for automotive mechanics and other fields that utilize hydraulics. The module contains 14 instructional units that cover the following topics: (1) introduction to hydraulics; (2) fundamentals of hydraulics; (3) reservoirs; (4) lines, fittings, and couplers; (5)…

  16. Leafminers help us understand leaf hydraulic design.

    PubMed

    Nardini, Andrea; Raimondo, Fabio; Lo Gullo, Maria A; Salleo, Sebastiano

    2010-07-01

    Leaf hydraulics of Aesculus hippocastanum L. were measured over the growing season and during extensive leaf mining by the larvae of an invasive moth (Cameraria ohridella Deschka et Dimic) that specifically destroy the palisade tissue. Leaves showed seasonal changes in hydraulic resistance (R(lamina)) which were related to ontogeny. After leaf expansion was complete, the hydraulic resistance of leaves and the partitioning of resistances between vascular and extra-vascular compartments remained unchanged despite extensive disruption of the palisade by leafminers (up to 50%). This finding suggests that water flow from the petiole to the evaporation sites might not directly involve the palisade cells. The analysis of the temperature dependence of R(lamina) in terms of Q(10) revealed that at least one transmembrane step was involved in water transport outside the leaf vasculature. Anatomical analysis suggested that this symplastic step may be located at the bundle sheath where the apoplast is interrupted by hydrophobic thickening of cell walls. Our findings offer some support to the view of a compartmentalization of leaves into well-organized water pools so that the transpiration stream would involve veins, bundle sheath and spongy parenchyma, while the palisade tissue would be largely by-passed with the possible advantage of protecting cells from short-term fluctuations in water status. PMID:20199625

  17. Hydraulic design and performance of a GCFR core assembly orifice

    SciTech Connect

    Tang, I.M.

    1980-02-01

    The design and performance of a core assembly orifice for gas-cooled fast-breeder reactors (GCFRs) are studied in this report. Successful reactor operation relies on adequate cooling, among other things, and orificing is important to cooling. A simple, yet effective, graphical design method for estimating the loss coefficient of an orifice and its associated opening area is presented. A numerical example is also provided for demonstration of the method. The effect of the orifice configuration on orifice hydraulic performance is discussed. The design method stated above provides a first estimate toward an orifice design. Hydraulic experiments are required for verification of the design adequacy.

  18. Hydraulics.

    ERIC Educational Resources Information Center

    Engelbrecht, Nancy; And Others

    These instructional materials provide an orientation to hydraulics for use at the postsecondary level. The first of 12 sections presents an introduction to hydraulics, including discussion of principles of liquids, definitions, liquid flow, the two types of hydraulic fluids, pressure gauges, and strainers and filters. The second section identifies…

  19. Hydraulic Design of Stepped Spillways Workshop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stepped chutes and spillways are commonly used for routing discharges during flood events. In addition, stepped chutes are used for overtopping protection of earthen embankments. Stepped spillways provide significant energy dissipation due to its stepped feature; as a result, the stilling basin as...

  20. Design of a portable hydraulic ankle-foot orthosis.

    PubMed

    Neubauer, Brett C; Nath, Jonathan; Durfee, William K

    2014-01-01

    Small-scale hydraulics is ideal for powered human assistive devices including powered ankle foot orthoses because a large torque can be generated with an actuator that is small and light. A portable hydraulic ankle foot orthosis has been designed and is undergoing preliminary prototyping and engineering bench test evaluation. The device provides 90 Nm of ankle torque and has an operating pressure of 138 bar (2,000 psi). The battery-operated hydraulic power supply weighs about 3 kg and is worn at the waist. The ankle component weighs about 1.2 Kg and connects to the power supply with two hoses. Performance simulation and preliminary bench testing suggests that the device could be useful in certain rehabilitation applications. PMID:25570175

  1. Conceptual design and cost analysis of hydraulic output unit for 15 kW free-piston Stirling engine

    NASA Technical Reports Server (NTRS)

    White, M. A.

    1982-01-01

    A long-life hydraulic converter with unique features was conceptually designed to interface with a specified 15 kW(e) free-piston Stirling engine in a solar thermal dish application. Hydraulic fluid at 34.5 MPa (5000 psi) is produced to drive a conventional hydraulic motor and rotary alternator. Efficiency of the low-maintenance converter design was calculated at 93.5% for a counterbalanced version and 97.0% without the counterbalance feature. If the converter were coupled to a Stirling engine with design parameters more typcial of high-technology Stirling engines, counterbalanced converter efficiency could be increased to 99.6%. Dynamic computer simulation studies were conducted to evaluate performance and system sensitivities. Production costs of the complete Stirling hydraulic/electric power system were evaluated at $6506 which compared with $8746 for an alternative Stirling engine/linear alternator system.

  2. New Design Feature in Virginia's Public Schools.

    ERIC Educational Resources Information Center

    Gillespie, Monica McTeague

    A study of new design features for public schools was conducted to determine what specific design features were being implemented in Virginia's schools. This report summarizes the major trends in facility design that were discovered in the following areas: safety and security features; classroom space; technology areas; administrative spaces;…

  3. Improved design of a bladed hydraulic balance ring

    NASA Astrophysics Data System (ADS)

    Urbiola-Soto, Leonardo; Lopez-Parra, Marcelo; Cuenca-Jimenez, Francisco

    2014-02-01

    The hydraulic self-balance ring is a very well-known kind of passive balancer of widespread use in the home appliances industry. Its conventional design consists of a hollow ring equipped with a number of anti-sloshing baffle boards of mainly straight shape situated inside the cavity. This paper introduces for the first time a hydraulic balance ring with curved baffles or blades. It is found that the forward blade shape is more suited to improve the transient-state response, whereas the backward blade shape remarkably enhances the steady-state response. A classical dynamics model of this novel bladed balance ring design is developed. Experimental data showing good correlation between the model and tests is also presented.

  4. Results From a Channel Restoration Project: Hydraulic Design Considerations

    USGS Publications Warehouse

    Karle, K.F.; Densmore, R.V.

    2001-01-01

    Techniques for the hydraulic restoration of placer-mined streams and floodplains were developed in Denali National Park and Preserve, Alaska. The two-year study at Glen Creek focused on a design of stream and floodplain geometry using hydraulic capacity and shear stress equations. Slope and sinuosity values were based on regional relationships. Design requirements included a channel capacity for a bankfull discharge and a floodplain capacity for a 1.5- to 100-year discharge. Several bio-engineering techniques using alder and willow, including anchored brush bars, streambank hedge layering, seedlings, and cuttings, were tested to dissipate floodwater energy and encourage sediment deposition until natural revegetation stabilized the new floodplains. Permanently monumented cross-sections installed throughout the project site were surveyed every one to three years. Nine years after the project began, a summer flood caused substantial damage to the channel form, including a change in width/depth ratio, slope, and thalweg location. Many of the alder brush bars were heavily damaged or destroyed, resulting in significant bank erosion. This paper reviews the original hydraulic design process, and describes changes to the channel and floodplain geometry over time, based on nine years of cross-section surveys.

  5. Screening of one-well hydraulic barrier design alternatives.

    PubMed

    Rubin, Hillel; Shoemaker, Christine A; Köngeter, Jürgen

    2008-01-01

    Abstract This study develops a robust method for screening one-well hydraulic barrier design alternatives that can be easily computed without a numerical simulation model. The paper outlines the general method and shows its implementation with hydraulic barriers using a single pumping well. For such barriers, the method is easily computable with spreadsheets and/or charts depicted within the paper and posted online. The method applies the potential flow theory, which leads to using a curvilinear coordinate system for all types of calculations. For contaminant transport calculations, the method applies the boundary layer theory. For calculations of aquifer remediation, the method refers to bulk characteristics of the domain. As an example, the method has been applied to calculate the possible containment of a wide part of the coastal plain aquifer in Israel, which is contaminated by entrapped kerosene (a light nonaqueous phase liquid). PMID:18266729

  6. Fault diagnosis of automobile hydraulic brake system using statistical features and support vector machines

    NASA Astrophysics Data System (ADS)

    Jegadeeshwaran, R.; Sugumaran, V.

    2015-02-01

    Hydraulic brakes in automobiles are important components for the safety of passengers; therefore, the brakes are a good subject for condition monitoring. The condition of the brake components can be monitored by using the vibration characteristics. On-line condition monitoring by using machine learning approach is proposed in this paper as a possible solution to such problems. The vibration signals for both good as well as faulty conditions of brakes were acquired from a hydraulic brake test setup with the help of a piezoelectric transducer and a data acquisition system. Descriptive statistical features were extracted from the acquired vibration signals and the feature selection was carried out using the C4.5 decision tree algorithm. There is no specific method to find the right number of features required for classification for a given problem. Hence an extensive study is needed to find the optimum number of features. The effect of the number of features was also studied, by using the decision tree as well as Support Vector Machines (SVM). The selected features were classified using the C-SVM and Nu-SVM with different kernel functions. The results are discussed and the conclusion of the study is presented.

  7. The hydraulic design of pump turbine for Xianyou pumped storage power station

    NASA Astrophysics Data System (ADS)

    Zheng, J. S.; Liu, W. C.; Fu, Z. Y.; Shi, Q. H.

    2012-11-01

    This paper presents the hydraulic design of pump turbines for Xianyou pumped storage power station. The method of improving the hydraulic performance of pump turbine with CFD analysis is given. The results of model test indicate that the final hydraulic design of pump turbine for Xianyou pumped storage power station is of high efficiencies, good

  8. Resolution of thermal-hydraulic safety and licensing issues for the system 80+{sup {trademark}} design

    SciTech Connect

    Carpentino, S.E.; Ritterbusch, S.E.; Schneider, R.E.

    1995-09-01

    The System 80+{sup {trademark}} Standard Design is an evolutionary Advanced Light Water Reactor (ALWR) with a generating capacity of 3931 MWt (1350 MWe). The Final Design Approval (FDA) for this design was issued by the Nuclear Regulatory Commission (NRC) in July 1994. The design certification by the NRC is anticipated by the end of 1995 or early 1996. NRC review of the System 80+ design has involved several new safety issues never before addressed in a regulatory atmosphere. In addition, conformance with the Electric Power Research Institute (EPRI) ALWR Utility Requirements Document (URD) required that the System 80+ plant address nuclear industry concerns with regard to design, construction, operation and maintenance of nuclear power plants. A large number of these issues/concerns deals with previously unresolved generic thermal-hydraulic safety issues and severe accident prevention and mitigation. This paper discusses the thermal-hydraulic analyses and evaluations performed for the System 80+ design to resolve safety and licensing issues relevant to both the Nuclear Stream Supply System (NSSS) and containment designs. For the NSSS design, the Safety Depressurization System mitigation capability and resolution of the boron dilution concern are described. Examples of containment design issues dealing with containment shell strength, robustness of the reactor cavity walls and hydrogen mixing under severe accident conditions are also provided. Finally, the overall approach used in the application of NRC`s new (NUREG-1465) radiological source term for System 80+ evaluation is described. The robustness of the System 80+ containment design to withstand severe accident consequences was demonstrated through detailed thermal-hydraulic analyses and evaluations. This advanced design to shown to meet NRC severe accident policy goals and ALWR URD requirements without any special design features and unnecessary costs.

  9. Integration of Supportive Design Features and Technology

    ERIC Educational Resources Information Center

    Lazaros, Edward J.; Ahmadi, Reza

    2008-01-01

    Integrating supportive design features and technology into the home are excellent ways to plan to make a home "age-friendly." When an immediate need occurs for eliminating barriers in an existing home, supportive design features and technology will most often need to be examined, and some form of implementation will need to take place. While…

  10. Dynamics and design of a power unit with a hydraulic piston actuator

    NASA Astrophysics Data System (ADS)

    Misyurin, S. Yu.; Kreinin, G. V.

    2016-07-01

    The problem of the preselection of parameters of a power unit of a mechatronic complex on the basis of the condition for providing a required control energy has been discussed. The design of the unit is based on analysis of its dynamics under the effect of a special-type test conditional control signal. The specific features of the approach used are a reasonably simplified normalized dynamic model of the unit and the formation of basic similarity criteria. Methods of designing a power unit with a hydraulic piston actuator that operates in point-to-point and oscillatory modes have been considered.

  11. Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory

    SciTech Connect

    Kress, R.L.; Jansen, J.F.; Love, L.J.; Basher, A.M.H.

    1996-09-01

    To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned to hydraulics as a means of actuation. Hydraulics have always been the actuator of choice when designing heavy-life construction and mining equipment such as bulldozers, backhoes, and tunneling devices. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem) sophisticated modeling, analysis, and control experiments are usually needed. To support the development and deployment of new hydraulic manipulators Oak Ridge National Laboratory (ORNL) has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The hydraulics laboratory at ORNL has three different manipulators. First is a 6-Degree-of-Freedom (6-DoF), multi-planer, teleoperated, flexible controls test bed used for the development of waste tank clean-up manipulator controls, thermal studies, system characterization, and manipulator tracking. Finally, is a human amplifier test bed used for the development of an entire new class of teleoperated systems. To compliment the hardware in the hydraulics laboratory, ORNL has developed a hydraulics simulation capability including a custom package to model the hydraulic systems and manipulators for performance studies and control development. This paper outlines the history of hydraulic manipulator developments at ORNL, describes the hydraulics laboratory, discusses the use of the equipment within the laboratory, and presents some of the initial results from experiments and modeling associated with these hydraulic manipulators. Included are some of the results from the development of the human amplifier/de-amplifier concepts, the characterization of the thermal sensitivity of hydraulic systems, and end-point tracking accuracy studies. Experimental and analytical

  12. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hydraulic or pneumatic power and control-materials and... Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component (such as pipe runs, fittings, flanges, and standard valves) for hydraulic or pneumatic power and...

  13. Design of a Resistively Heated Thermal Hydraulic Simulator for Nuclear Rocket Reactor Cores

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Foote, John P.; Ramachandran, Narayanan; Wang, Ten-See; Anghaie, Samim

    2007-01-01

    A preliminary design study is presented for a non-nuclear test facility which uses ohmic heating to replicate the thermal hydraulic characteristics of solid core nuclear reactor fuel element passages. The basis for this testing capability is a recently commissioned nuclear thermal rocket environments simulator, which uses a high-power, multi-gas, wall-stabilized constricted arc-heater to produce high-temperature pressurized hydrogen flows representative of reactor core environments, excepting radiation effects. Initially, the baseline test fixture for this non-nuclear environments simulator was configured for long duration hot hydrogen exposure of small cylindrical material specimens as a low cost means of evaluating material compatibility. It became evident, however, that additional functionality enhancements were needed to permit a critical examination of thermal hydraulic effects in fuel element passages. Thus, a design configuration was conceived whereby a short tubular material specimen, representing a fuel element passage segment, is surrounded by a backside resistive tungsten heater element and mounted within a self-contained module that inserts directly into the baseline test fixture assembly. With this configuration, it becomes possible to create an inward directed radial thermal gradient within the tubular material specimen such that the wall-to-gas heat flux characteristics of a typical fuel element passage are effectively simulated. The results of a preliminary engineering study for this innovative concept are fully summarized, including high-fidelity multi-physics thermal hydraulic simulations and detailed design features.

  14. Hydraulic design of a low-specific speed Francis runner for a hydraulic cooling tower

    NASA Astrophysics Data System (ADS)

    Ruan, H.; Luo, X. Q.; Liao, W. L.; Zhao, Y. P.

    2012-11-01

    The air blower in a cooling tower is normally driven by an electromotor, and the electric energy consumed by the electromotor is tremendous. The remaining energy at the outlet of the cooling cycle is considerable. This energy can be utilized to drive a hydraulic turbine and consequently to rotate the air blower. The purpose of this project is to recycle energy, lower energy consumption and reduce pollutant discharge. Firstly, a two-order polynomial is proposed to describe the blade setting angle distribution law along the meridional streamline in the streamline equation. The runner is designed by the point-to-point integration method with a specific blade setting angle distribution. Three different ultra-low-specificspeed Francis runners with different wrap angles are obtained in this method. Secondly, based on CFD numerical simulations, the effects of blade setting angle distribution on pressure coefficient distribution and relative efficiency have been analyzed. Finally, blade angles of inlet and outlet and control coefficients of blade setting angle distribution law are optimal variables, efficiency and minimum pressure are objective functions, adopting NSGA-II algorithm, a multi-objective optimization for ultra-low-specific speed Francis runner is carried out. The obtained results show that the optimal runner has higher efficiency and better cavitation performance.

  15. A Thermoelastic Hydraulic Fracture Design Tool for Geothermal Reservoir Development

    SciTech Connect

    Ahmad Ghassemi

    2003-06-30

    Geothermal energy is recovered by circulating water through heat exchange areas within a hot rock mass. Geothermal reservoir rock masses generally consist of igneous and metamorphic rocks that have low matrix permeability. Therefore, cracks and fractures play a significant role in extraction of geothermal energy by providing the major pathways for fluid flow and heat exchange. Thus, knowledge of conditions leading to formation of fractures and fracture networks is of paramount importance. Furthermore, in the absence of natural fractures or adequate connectivity, artificial fracture are created in the reservoir using hydraulic fracturing. At times, the practice aims to create a number of parallel fractures connecting a pair of wells. Multiple fractures are preferred because of the large size necessary when using only a single fracture. Although the basic idea is rather simple, hydraulic fracturing is a complex process involving interactions of high pressure fluid injections with a stressed hot rock mass, mechanical interaction of induced fractures with existing natural fractures, and the spatial and temporal variations of in-situ stress. As a result it is necessary to develop tools that can be used to study these interactions as an integral part of a comprehensive approach to geothermal reservoir development, particularly enhanced geothermal systems. In response to this need we have set out to develop advanced thermo-mechanical models for design of artificial fractures and rock fracture research in geothermal reservoirs. These models consider the significant hydraulic and thermo-mechanical processes and their interaction with the in-situ stress state. Wellbore failure and fracture initiation is studied using a model that fully couples poro-mechanical and thermo-mechanical effects. The fracture propagation model is based on a complex variable and regular displacement discontinuity formulations. In the complex variable approach the displacement discontinuities are

  16. Hydraulic fracturing model featuring initiation beyond the wellbore wall for directional well in coal bed

    NASA Astrophysics Data System (ADS)

    Li, Yuwei; Jia, Dan; Wang, Meng; Liu, Jia; Fu, Chunkai; Yang, Xinliang; Ai, Chi

    2016-08-01

    In developing internal fracture systems in coal beds, the initiation mechanism differs greatly from that of conventional ones and initiations may be produced beyond the wellbore wall. This paper describes the features of the internal structure of coal beds and RFPA2D simulation is used to attest the possible occurrence of initiation beyond the wellbore wall in coal bed hydraulic fracturing. Using the theory of elasticity and fracture mechanics, we analyse the stress distribution in the vicinal coal rock. Then by taking into consideration the effects of the spatial relationship between coal bed cleats and the wellbore, we establish a model for calculating both tensile and shear initiation pressure that occur along cleats beyond the wellbore wall. The simulation in this paper indicates that for shear initiations that happen along coal cleats, the pressure required to initiate fracture for cleats beyond the wellbore wall is evidently lower than that on the wellbore wall, thus it is easier to initiate shear fractures for cleats beyond the wellbore wall. For tensile failure, the pressure required to initiate tensile fracture for cleats beyond the wellbore wall is obviously higher than that for cleats at the wellbore wall, thus it is easier to initiate tensile fractures for cleats at the wellbore wall. On the one hand, this paper has proved the possible occurrence of initiations beyond the wellbore wall and has changed the current assumption that hydraulic fractures can only occur at the wellbore wall. On the other hand, the established theoretical model provides a new approach to calculating the initiation pressure in hydraulic fracturing.

  17. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component... 46 Shipping 4 2014-10-01 2014-10-01 false Hydraulic or pneumatic power and control-materials...

  18. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component... 46 Shipping 4 2011-10-01 2011-10-01 false Hydraulic or pneumatic power and control-materials...

  19. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component... 46 Shipping 4 2012-10-01 2012-10-01 false Hydraulic or pneumatic power and control-materials...

  20. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component... 46 Shipping 4 2013-10-01 2013-10-01 false Hydraulic or pneumatic power and control-materials...

  1. Extraction of features from ultrasound acoustic emissions: a tool to assess the hydraulic vulnerability of Norway spruce trunkwood?

    PubMed Central

    Rosner, Sabine; Klein, Andrea; Wimmer, Rupert; Karlsson, Bo

    2011-01-01

    Summary • The aim of this study was to assess the hydraulic vulnerability of Norway spruce (Picea abies) trunkwood by extraction of selected features of acoustic emissions (AEs) detected during dehydration of standard size samples. • The hydraulic method was used as the reference method to assess the hydraulic vulnerability of trunkwood of different cambial ages. Vulnerability curves were constructed by plotting the percentage loss of conductivity vs an overpressure of compressed air. • Differences in hydraulic vulnerability were very pronounced between juvenile and mature wood samples; therefore, useful AE features, such as peak amplitude, duration and relative energy, could be filtered out. The AE rates of signals clustered by amplitude and duration ranges and the AE energies differed greatly between juvenile and mature wood at identical relative water losses. • Vulnerability curves could be constructed by relating the cumulated amount of relative AE energy to the relative loss of water and to xylem tension. AE testing in combination with feature extraction offers a readily automated and easy to use alternative to the hydraulic method. PMID:16771986

  2. Fluvial Features on Titan: New Insights from Morphology and Hydraulic Modeling

    NASA Astrophysics Data System (ADS)

    Burr, D. M.; Adamkovics, M.; Baker, V. R.; Collins, G. C.; Howard, A. D.; Irwin, R. P.; Lamb, M. P.; Moore, J. M.; Perron, T.; Sklar, L. S.; Drummond, S.; Black, B. A.

    2011-12-01

    Fluvial features on Titan have been inferred in data from surface imaging instruments on the Cassini spacecraft (Image Science Subsystem, ISS; Visual and Infrared Mapping Spectrometer, VIMS; Cassini Titan RADAR Mapper, RADAR) and the Huygens probe (Descent Imager/Spectral Radiometer, DISR). Interpretations of these features using terrestrial classifications and analogs offer insight into their formative processes and controls. Networks may be classified using a modified version of an algorithm developed from terrestrial drainage networks. As each network class carries different landscape-scale implications, these classifications provide information on the regional geology. For example, rectangular networks, the dominant drainage pattern on Titan, imply structural control. Individual fluvial features provide more localized information and may be classified using simple plan view parameters of relative width, length, and RADAR albedo into six descriptive classes, which have multiple hypothesized interpretations. At the highest resolution observations of Titan, DISR images show uplands dissected by river valley networks, which are not visible in lower resolution SAR data. This comparison of DISR and SAR images suggests (1) that some fluvial features observed in SAR data elsewhere may be river valleys instead of channels as previously denoted, and (2) that other uplands on Titan may likewise be fluvially dissected below SAR resolution. Crenulated (mountainous, hummocky) terrain is hypothesized here to have such sub-resolution fluvial dissection, based on (a) emergent fluvial features at lakes and (b) terrestrial data over dissected landscapes that illustrate the underrepresentation of fluvial dissection in SAR data. Fluvial deposits occur in (paleo)lake basins and on SAR-dark plains. For fully turbulent flow over a rough boundary, hydraulic equations are insensitive to fluid viscosity, so that terrestrial formulations are applicable to Titan flow when the difference in

  3. Statistical and geostatistical features of streambed hydraulic conductivities in the Platte River, Nebraska

    NASA Astrophysics Data System (ADS)

    Chen, Xunhong

    2005-09-01

    This paper presents streambed hydraulic conductivities of the Platte River from south-central to eastern Nebraska. The hydraulic conductivities were determined from river channels using permeameter tests. The vertical hydraulic conductivities ( K v ) from seven test sites along this river in south-central Nebraska belong to one statistical population. Its mean value is 40.2 m/d. However, the vertical hydraulic conductivities along four transects of the Ashland test site in eastern Nebraska have lower mean values, are statistically different from the K v values in south-central Nebraska, and belong to two different populations with mean values of 20.7 and 9.1 m/d, respectively. Finer sediments carried from the Loup River and Elkhorn River watersheds to the eastern reach of the Platte River lowers the vertical hydraulic conductivity of the streambed. Correlation coefficients between water depth and K v values along a test transect indicates a positive correlation a larger K v usually occurs in the part of channel with deeper water. Experimental variograms derived from the vertical hydraulic conductivities for several transects across the channels of the Platte River show periodicity of spatial correlation, which likely result from periodic variation of water depth across the channels. The sandy to gravelly streambed contains very local silt and clay layers; spatially continuous low-permeability streambed was not observed in the river channels. The horizontal hydraulic conductivities were larger than the vertical hydraulic conductivities for the same test locations.

  4. CAL Packages for Civil Engineering Hydraulics and Structural Design.

    ERIC Educational Resources Information Center

    Moss, W. D.; And Others

    1979-01-01

    Describes computer assisted learning (CAL) packages written in FORTRAN IV and developed for use in a degree course in civil engineering dealing with hydraulics and structures. All are used in the interactive mode through a terminal with a keyboard and visual display unit. (Author/CMV)

  5. Isotope Production Facility Conceptual Thermal-Hydraulic Design Review and Scoping Calculations

    SciTech Connect

    Pasamehmetoglu, K.O.; Shelton, J.D.

    1998-08-01

    The thermal-hydraulic design of the target for the Isotope Production Facility (IPF) is reviewed. In support of the technical review, scoping calculations are performed. The results of the review and scoping calculations are presented in this report.

  6. A hybrid, neuro-genetic approach to hydraulic fracture treatment design and optimization

    SciTech Connect

    Mohaghegh, S.; Balan, B.; Ameri, S.; McVey, D.S.

    1996-12-31

    This paper summarizes the efforts conducted toward the development of a new and novel methodology for optimal design of hydraulic fracture treatments in a gas storage field. What makes this methodology unique is its capability to provide engineers with a near optimum design of a frac job despite very little (almost none) reservoir data availability. Lack of engineering data for hydraulic fracture design and evaluation had made use of 2D or 3D hydraulic fracture simulators impractical. As a result, prior designs of hydraulic frac jobs had been reduced to guess works and in some cases dependent on engineers with many years of experience on this particular field, who had developed an intuition about this formation and its possible response to different treatments. This was the main cause of several frac job failures every year. On the other hand, in case of relocation of engineers with experience on this particular field the risk of even more frac job failures was imminent.

  7. Thermal Hydraulic Challenges of Gas Cooled Fast Reactors with Passive Safety Features

    SciTech Connect

    Michael Pope; Jeong-Ik Lee; Pavel Hejzlar; Michael J. Driscoll

    2009-05-01

    Transient response of a Gas cooled Fast Reactor (GFR) coupled to a recompression supercritical CO2 (S-CO2) power conversion system (PCS) in a direct cycle to Loss of Coolant and Loss of Generator Load Accidents is analyzed using RELAP5-3D. A number of thermal hydraulic challenges for GFR design are pointed out as the designers strive to accommodate cooling of the high power density core of a fast reactor by a gas with its inherently low heat transfer capability, in particular under post LOCA events when system pressure is lost and when reliance on passive decay heat removal is emphasized. Although it is possible to design a S-CO2 cooled GFR that can survive LOCA by cooling the core through natural circulating loops between the core and elevated emergency cooling heat exchangers, it is not an attractive approach because of various bypass paths that can, depending on break location, degrade core cooling. Moreover, natural circulation gas loops can operate in deteriorated heat transfer regimes with substantial reduction of heat transfer coefficient: as low as 30% of forced convection values, and data and correlations in these regimes carry large uncertainties. Therefore, reliable battery powered blowers for post-LOCA decay heat removal (DHR) that provide flow in well defined regimes with low uncertainty, and can be easily over-designed to accommodate bypass flows were selected. The results confirm that a GFR with such a DHR system and negative coolant void worth can withstand LOCA with and without scram as well as loss of electrical load without exceeding core temperature and turbomachinery overspeed limits.

  8. The hydraulic separator Multidune: preliminary tests on fluid-dynamic features and plastic separation feasibility.

    PubMed

    De Sena, Giulia; Nardi, Camillo; Cenedese, Antonio; La Marca, Floriana; Massacci, Paolo; Moroni, Monica

    2008-01-01

    Recycling of plastic materials is a rapidly developing discipline because of environmental awareness, the need to conserve materials and energy, and the growing demand to increase the production economy. The main problem in plastics recovery and recycling is related to the variety of plastic wastes, even if selective collection occurs. Therefore, plastic materials can be recycled either as mixtures or as single types, separating the different typologies by their physical (size, specific mass, etc.) and/or chemical properties. However, separation of plastics in single typologies by traditional processes and devices is difficult due to their typical low variability in properties. This paper presents a new research development for recycling industry: the Multidune separator. This is a device constructed from a sequence of parallel semi-cylindrical tubes of transparent plastic welded together in a plane. The lower half is shifted laterally and then fixed relative to the upper half. Flow is then induced in the lateral direction normal to the axis of the tubes, creating a main flow channel and two recirculation zones. This apparatus creates a differential transport of particles of low specific mass, near to 1g/cm3, allowing their separation. The flow field in the Multidune separator is studied via Particle Tracking Velocimetry (PTV). Eulerian analysis of the data is performed to gather information about the fluid-dynamics features established by different hydraulic heads at the inlet of the Multidune. Preliminary tests on monomaterial samples have been performed, varying several operative parameters to determine the best set of values. Therefore, separation tests have been executed on composite samples, obtaining satisfactory results in terms of plastic separation feasibility. PMID:17935965

  9. Design, test and model of a hybrid magnetostrictive hydraulic actuator

    NASA Astrophysics Data System (ADS)

    Chaudhuri, Anirban; Yoo, Jin-Hyeong; Wereley, Norman M.

    2009-08-01

    The basic operation of hybrid hydraulic actuators involves high frequency bi-directional operation of an active material that is converted to uni-directional motion of hydraulic fluid using valves. A hybrid actuator was developed using magnetostrictive material Terfenol-D as the driving element and hydraulic oil as the working fluid. Two different lengths of Terfenol-D rod, 51 and 102 mm, with the same diameter, 12.7 mm, were used. Tests with no load and with load were carried out to measure the performance for uni-directional motion of the output piston at different pumping frequencies. The maximum no-load flow rates were 24.8 cm3 s-1 and 22.7 cm3 s-1 with the 51 mm and 102 mm long rods respectively, and the peaks were noted around 325 Hz pumping frequency. The blocked force of the actuator was close to 89 N in both cases. A key observation was that, at these high pumping frequencies, the inertial effects of the fluid mass dominate over the viscous effects and the problem becomes unsteady in nature. In this study, we also develop a mathematical model of the hydraulic hybrid actuator in the time domain to show the basic operational principle under varying conditions and to capture phenomena affecting system performance. Governing equations for the pumping piston and output shaft were obtained from force equilibrium considerations, while compressibility of the working fluid was taken into account by incorporating the bulk modulus. Fluid inertia was represented by a lumped parameter approach to the transmission line model, giving rise to strongly coupled ordinary differential equations. The model was then used to calculate the no-load velocities of the actuator at different pumping frequencies and simulation results were compared with experimental data for model validation.

  10. 25 kWe solar thermal stirling hydraulic engine system: Final conceptual design report

    SciTech Connect

    Not Available

    1988-01-01

    This report documents the conceptual design and analysis of a solar thermal free-piston Stirling hydraulic engine system designed to deliver 25 kWe when coupled to the 11-meter Test Bed Concentrator at Sandia National Laboratories. A manufacturing cost assessment for 10,000 units per year was made by Pioneer Engineering and Manufacturing. The design meets all program objectives including a 60,000-hr design life, dynamic balancing, fully automated control, >33.3% overall system efficiency, properly conditioned power, maximum utilization of annualized insolation, and projected production costs of $300/kW. The system incorporates a simple, rugged, reliable pool boiler reflux heat pipe to transfer heat from the solar receiver to the Stirling engine. The free-piston engine produces high-pressure hydraulic flow which powers a commercial hydraulic motor that, in turn, drives a commercial rotary induction generator. The Stirling hydraulic engine uses hermetic bellows seals to separate helium working gas from hydraulic fluid which provides hydrodynamic lubrication to all moving parts. Maximum utilization of highly refined, field proven commercial components for electric power generation minimizes development cost and risk. The engine design is based on a highly refined Stirling hydraulic engine developed over 20 years as a fully implantable artificial heart power source. 4 refs., 19 figs., 3 tabs.

  11. Passive Safety Features in Advanced Nuclear Power Plant Design

    NASA Astrophysics Data System (ADS)

    Tahir, M.; Chughtai, I. R.; Aslam, M.

    2013-03-01

    For implementation of advance passive safety features in future nuclear power plant design, a passive safety system has been proposed and its response has been observed for Loss of Coolant Accident (LOCA) in the cold leg of a reactor coolant system. In a transient simulation the performance of proposed system is validated against existing safety injection system for a reference power plant of 325 MWe. The existing safety injection system is a huge system and consists of many active components including pumps, valves, piping and Instrumentation and Control (I&C). A good running of the active components of this system is necessary for its functionality as high head safety injection system under design basis accidents. Using reactor simulation technique, the proposed passive safety injection system and existing safety injection system are simulated and tested for their performance under large break LOCA for the same boundary conditions. Critical thermal hydraulic parameters of both the systems are presented graphically and discussed. The results obtained are approximately the same in both the cases. However, the proposed passive safety injection system is a better choice for such type of reactors due to reduction in components with improved safety.

  12. Design of a hydraulic actuator for active control of rotating machinery

    NASA Technical Reports Server (NTRS)

    Rashidi, Majid; Dirusso, Eliseo

    1991-01-01

    A hydraulic actuator is described which consists of a pump, a hydraulic servo-valve, and a thin elastic plate which transduces the generated pressure variations into forces acting on a mass which simulates the bearing of a rotor system. An actuator characteristic number is defined to provide a base for an optimum design of force actuators with combined weight, frequency, and force considerations. This characteristic number may also be used to compare hydraulic and electromagnetic force actuators. In tests, this actuator generated 182.3 Newton force at a frequency of 100 Hz and a displacement amplitude of 5.8 x 10 exp -5 meter.

  13. Hydraulic performance numerical simulation of high specific speed mixed-flow pump based on quasi three-dimensional hydraulic design method

    NASA Astrophysics Data System (ADS)

    Zhang, Y. X.; Su, M.; Hou, H. C.; Song, P. F.

    2013-12-01

    This research adopts the quasi three-dimensional hydraulic design method for the impeller of high specific speed mixed-flow pump to achieve the purpose of verifying the hydraulic design method and improving hydraulic performance. Based on the two families of stream surface theory, the direct problem is completed when the meridional flow field of impeller is obtained by employing iterative calculation to settle the continuity and momentum equation of fluid. The inverse problem is completed by using the meridional flow field calculated in the direct problem. After several iterations of the direct and inverse problem, the shape of impeller and flow field information can be obtained finally when the result of iteration satisfies the convergent criteria. Subsequently the internal flow field of the designed pump are simulated by using RANS equations with RNG k-ε two-equation turbulence model. The static pressure and streamline distributions at the symmetrical cross-section, the vector velocity distribution around blades and the reflux phenomenon are analyzed. The numerical results show that the quasi three-dimensional hydraulic design method for high specific speed mixed-flow pump improves the hydraulic performance and reveal main characteristics of the internal flow of mixed-flow pump as well as provide basis for judging the rationality of the hydraulic design, improvement and optimization of hydraulic model.

  14. Recent Development of the Two-Stroke Engine. II - Design Features. 2; Design Features

    NASA Technical Reports Server (NTRS)

    Zeman, J.

    1945-01-01

    Completing the first paper dealing with charging methods and arrangements, the present paper discusses the design forms of two-stroke engines. Features which largely influence piston running are: (a) The shape and surface condition of the sliding parts. (b) The cylinder and piston materials. (c) Heat conditions in the piston, and lubrication. There is little essential difference between four-stroke and two-stroke engines with ordinary pistons. In large engines, for example, are always found separately cast or welded frames in which the stresses are taken up by tie rods. Twin piston and timing piston engines often differ from this design. Examples can be found in many engines of German or foreign make. Their methods of operation will be dealt with in the third part of the present paper, which also includes the bibliography. The development of two-stroke engine design is, of course, mainly concerned with such features as are inherently difficult to master; that is, the piston barrel and the design of the gudgeon pin bearing. Designers of four-stroke engines now-a-days experience approximately the same difficulties, since heat stresses have increased to the point of influencing conditions in the piston barrel. Features which notably affect this are: (a) The material. (b) Prevailing heat conditions.

  15. Richards Barrier LA Reference Design Feature Evaluation

    SciTech Connect

    N.E. Kramer

    1999-11-17

    The Richards Barrier is one of the design features of the repository to be considered for the License Application (LA), Richards was a soil scientist who first described the diversion of moisture between two materials with different hydrologic properties. In this report, a Richards Barrier is a special type of backfill with a fine-grained material (such as sand) overlaying a coarse-grained material (such as gravel). Water that enters an emplacement drift will first encounter the fine-grained material and be transported around the coarse-grained material covering the waste package, thus protecting the waste package from contact with most of the groundwater. The objective of this report is to discuss the benefits and liabilities to the repository by the inclusion of a Richards Barrier type backfill in emplacement drifts. The Richards Barrier can act as a barrier to water flow, can reduce the waste package material dissolution rate, limit mobilization of the radionuclides, and can provide structural protection for the waste package. The scope of this report is to: (1) Analyze the behavior of barrier materials following the intrusion of groundwater for influxes of 1 to 300 mm per year. The report will demonstrate diversion of groundwater intrusions into the barrier over an extended time period when seismic activity and consolidation may cause the potential for liquefaction and settlement of the Richards Barrier. (2) Review the thermal effects of the Richards Barrier on material behavior. (3) Analyze the effect of rockfall on the performance of the Richards Barrier and the depth of the barrier required to protect waste packages under the barrier. (4) Review radiological and heating conditions on placement of multiple layers of the barrier. Subsurface Nuclear Safety personnel will perform calculations to determine the radiation reduction-time relationship and shielding capacity of the barrier. (5) Evaluate the effects of ventilation on cooling of emplacement drifts and

  16. FFTF thermal-hydraulic testing results affecting piping and vessel component design in LMFBR's

    SciTech Connect

    Stover, R.L.; Beaver, T.R.; Chang, S.C.

    1983-01-01

    The Fast Flux Test Facility completed four years of pre-operational testing in April 1982. This paper describes thermal-hydraulic testing results from this period which impact piping and vessel component design in LMFBRs. Data discussed are piping flow oscillations, piping thermal stratification and vessel upper plenum stratification. Results from testing verified that plant design limits were met.

  17. Application of FLUIDNET-G software to the preliminary thermal and hydraulic design of Hermes spaceplane

    NASA Astrophysics Data System (ADS)

    Chelotti, Jean-Noel; Andre, Serge; Maciaszek, Thierry; Thuaire, Alain; Ferro, Alain

    1992-07-01

    FLUIDNET-G, a workstation-run graphics-software package, performs thermal and hydraulic preliminary design tasks for single-phase fluid-loop systems. Both tradeoff and sensitivity studies may be conducted, as is presently illustrated for the case of the Hermes radiator system. Extensive examples are given of the FLUIDNET-G system's graphics for the design problems discussed.

  18. The 25 kWe solar thermal Stirling hydraulic engine system: Conceptual design

    NASA Technical Reports Server (NTRS)

    White, Maurice; Emigh, Grant; Noble, Jack; Riggle, Peter; Sorenson, Torvald

    1988-01-01

    The conceptual design and analysis of a solar thermal free-piston Stirling hydraulic engine system designed to deliver 25 kWe when coupled to a 11 meter test bed concentrator is documented. A manufacturing cost assessment for 10,000 units per year was made. The design meets all program objectives including a 60,000 hr design life, dynamic balancing, fully automated control, more than 33.3 percent overall system efficiency, properly conditioned power, maximum utilization of annualized insolation, and projected production costs. The system incorporates a simple, rugged, reliable pool boiler reflux heat pipe to transfer heat from the solar receiver to the Stirling engine. The free-piston engine produces high pressure hydraulic flow which powers a commercial hydraulic motor that, in turn, drives a commercial rotary induction generator. The Stirling hydraulic engine uses hermetic bellows seals to separate helium working gas from hydraulic fluid which provides hydrodynamic lubrication to all moving parts. Maximum utilization of highly refined, field proven commercial components for electric power generation minimizes development cost and risk.

  19. Final design of a free-piston hydraulic advanced Stirling conversion system

    NASA Astrophysics Data System (ADS)

    Wallace, D. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

    Under the US Department of Energy's (DOEs) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for solar distributed receiver systems. The final design is described of an engineering prototype advanced Stirling conversion system (ASCS) with a free-piston hydraulic engine output capable of delivering about 25 kW of electric power to a utility grid. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, has noncontacting bearings, and can be hermetically sealed. The ASCS is designed to deliver maximum power per year over a range of solar input with a design life of 30 years (60,000 h). The system includes a liquid Nak pool boiler heat transport system and a free-piston Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator.

  20. Final design of a free-piston hydraulic advanced Stirling conversion system

    NASA Technical Reports Server (NTRS)

    Wallace, D. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

    1991-01-01

    Under the US Department of Energy's (DOEs) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for solar distributed receiver systems. The final design is described of an engineering prototype advanced Stirling conversion system (ASCS) with a free-piston hydraulic engine output capable of delivering about 25 kW of electric power to a utility grid. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, has noncontacting bearings, and can be hermetically sealed. The ASCS is designed to deliver maximum power per year over a range of solar input with a design life of 30 years (60,000 h). The system includes a liquid Nak pool boiler heat transport system and a free-piston Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator.

  1. Feed-pump hydraulic performance and design improvement, Phase I: research program design. Final report

    SciTech Connect

    Brown, W.H.; Gopalakrishnan, S.; Fehlau, R.; Thompson, W.E.; Wilson, D.G.

    1982-03-01

    As a result of prior EPRI-sponsored studies, it was concluded that a research program should be designed and implemented to provide an improved basis for the design, procurement, testing, and operation of large feed pumps with increased reliability and stability over the full range of operating conditions. This two-volume report contains a research plan which is based on a review of the present state of the art and which defines the necessary R and D program and estimates the benefits and costs of the program. The recommended research program consists of 30 interrelated tasks. It is designed to perform the needed research; to verify the results; to develop improved components; and to publish computer-aided design methods, pump specification guidelines, and a troubleshooting manual. Most of the technology proposed in the research plan is applicable to nuclear power plants as well as to fossil-fired plants. This volume contains appendixes on pump design, cavitation damage, performance testing, hydraulics, two-phase flow in pumps, flow stability, and rotor dynamics.

  2. A survey on methods of design features identification

    NASA Astrophysics Data System (ADS)

    Grabowik, C.; Kalinowski, K.; Paprocka, I.; Kempa, W.

    2015-11-01

    It is widely accepted that design features are one of the most attractive integration method of most fields of engineering activities such as a design modelling, process planning or production scheduling. One of the most important tasks which are realized in the integration process of design and planning functions is a design translation meant as design data mapping into data which are important from process planning needs point of view, it is manufacturing data. A design geometrical shape translation process can be realized with application one of the following strategies: (i) designing with previously prepared design features library also known as DBF method it is design by feature, (ii) interactive design features recognition IFR, (iii) automatic design features recognition AFR. In case of the DBF method design geometrical shape is created with design features. There are two basic approaches for design modelling in DBF method it is classic in which a part design is modelled from beginning to end with application design features previously stored in a design features data base and hybrid where part is partially created with standard predefined CAD system tools and the rest with suitable design features. Automatic feature recognition consist in an autonomic searching of a product model represented with a specific design representation method in order to find those model features which might be potentially recognized as design features, manufacturing features, etc. This approach needs the searching algorithm to be prepared. The searching algorithm should allow carrying on the whole recognition process without a user supervision. Currently there are lots of AFR methods. These methods need the product model to be represented with B-Rep representation most often, CSG rarely, wireframe very rarely. In the IFR method potential features are being recognized by a user. This process is most often realized by a user who points out those surfaces which seem to belong to a

  3. Comparison of hydraulic and hemolytic properties of different impeller designs of an implantable rotary blood pump by computational fluid dynamics.

    PubMed

    Arvand, Arash; Hahn, Nicole; Hormes, Marcus; Akdis, Mustafa; Martin, Michael; Reul, Helmut

    2004-10-01

    A mixed-flow blood pump for long-term applications has been developed at the Helmholtz-Institute in Aachen, Germany. Central features of this implantable pump are a centrally integrated motor, a blood-immersed mechanical bearing, magnetic coupling of the impeller, and a shrouded impeller, which allows a relatively wide clearance. The aim of the study was a numerical analysis of hydraulic and hemolytic properties of different impeller design configurations. In vitro testing and numerical simulation techniques (computational fluid dynamics [CFD]) were applied to achieve a comprehensive overview. Pressure-flow charts were experimentally measured in a mock loop in order to validate the CFD data. In vitro hemolysis tests were performed at the main operating point of each impeller design. General flow patterns, pressure-flow charts, secondary flow rates, torque, and axial forces on the impeller were calculated by means of CFD. Furthermore, based on streak line techniques, shear stress (stress loading), exposure times, and volume percentage with critical stress loading have been determined. Comparison of CFD data with pressure head measurements showed excel-lent agreement. Also, impressive trend conformity was observed between in-vitro hemolysis results and numerical data. Comparison of design variations yielded clear trends and results. Design C revealed the best hydraulic and hemolytic properties and was chosen as the final design for the mixed-flow rotary blood pump. PMID:15384994

  4. AP600 design certification thermal hydraulics testing and analysis

    SciTech Connect

    Hochreiter, L.E.; Piplica, E.J.

    1995-09-01

    Westinghouse Electric Corporation, in conjunction with the Department of Energy and the Electric Power Research Institute, have been developing an advanced light water reactor design; the AP600. The AP600 is a 1940 Mwt, 600Mwe unit which is similar to a Westinghouse two-loop Pressurized Water Reactor. The accumulated knowledge on reactor design to reduce the capital costs, construction time, and the operational and maintenance cost of the unit once it begins to generate electrical power. The AP600 design goal is to maintain an overall cost advantage over fossil generated electrical power.

  5. Use of hydraulic models to identify and resolve design isssues in FGD systems

    SciTech Connect

    Strock, T.W.; Gohara, W.F.

    1995-06-01

    The hydraulics within a wet flue gas desulfurization (FGD) scrubber involve several complex two-phase gas/liquid interactions that directly affect the scrubber pressure drop, mist elimination efficiency, and the mass transfer process of SO{sub 2} removal. Current industrial efforts to develop cost effective, high-efficiency wet FGD scrubbers are focusing, in part, on the hydraulics. The development of an experimental approach and test facility for understanding and optimizing wet scrubber flow characteristics has been completed. Hydraulic models simulate full-scale units and allow the designer to view the gas/liquid flow interactions. Modeling procedures for downsizing the wet scrubber for the laboratory have been developed and validated with field data comparisons. A one-eighth scale hydraulic model has been used to study several FGD scrubber design issues. Design changes to reduce capital and operating cost have been developed and tested. Recently, the model was used to design a commercial, uniform flow, high gas velocity absorber for the next generation of FGD systems.

  6. Application of FLUIDNET-G software to the preliminary thermal and hydraulic design of Hermes spaceplane

    NASA Astrophysics Data System (ADS)

    Chelotti, J. N.; Andre, S.; Maciaszek, T.; Thuaire, A.; Ferro, A.

    FLUIDNET-G is a 'workstation' based graphic's orientated software package. The package performs single phase fluid loop thermal and hydraulic preliminary design. The main characteristics of this tool are as follows: the user friendliness of the graphics and the workstation concept; and the 'upstream compatibility' towards others analysis tools. An application illustrates FLUIDNET-G's ability to perform tradeoff and sensitivity studies.

  7. The Process of Designing Task Features

    ERIC Educational Resources Information Center

    Bauer, Malcolm

    2014-01-01

    Malcolm Bauer, from Education Testing Services, provides his comments on the Focus article in this issue of "Measurement" entitled : "How Task Features Impact Evidence from Assessments Embedded in Simulations and Games" (Russell G. Almond, Yoon Jeon Kim, Gertrudes Velasquez, Valerie J. Shute). Bauer begins his remarks by noting…

  8. Numerical Modeling of a Thermal-Hydraulic Loop and Test Section Design for Heat Transfer Studies in Supercritical Fluids

    NASA Astrophysics Data System (ADS)

    McGuire, Daniel

    A numerical tool for the simulation of the thermal dynamics of pipe networks with heat transfer has been developed with the novel capability of modeling supercritical fluids. The tool was developed to support the design and deployment of two thermal-hydraulic loops at Carleton University for the purpose of heat transfer studies in supercritical and near-critical fluids. First, the system was characterized based on its defining features; the characteristic length of the flow path is orders of magnitude larger than the other characteristic lengths that define the system's geometry; the behaviour of the working fluid in the supercritical thermodynamic state. An analysis of the transient thermal behaviour of the model's domains is then performed to determine the accuracy and range of validity of the modeling approach for simulating the transient thermal behaviour of a thermal-hydraulic loop. Preliminary designs of three test section geometries, for the purpose of heat transfer studies, are presented in support of the overall design of the Carleton supercritical thermal-hydraulic loops. A 7-rod-bundle, annular and tubular geometries are developed with support from the new numerical tool. Materials capable of meeting the experimental requirements while operating in supercritical water are determined. The necessary geometries to satisfy the experimental goals are then developed based on the material characteristics and predicted heat transfer behaviour from previous simulation results. An initial safety analysis is performed on the test section designs, where they are evaluated against the ASME Boiler, Pressure Vessel, and Pressure Piping Code standard, required for safe operation and certification.

  9. Design features of fans, blowers, and compressors

    NASA Astrophysics Data System (ADS)

    Cheremisinoff, N. P.; Cheremisinoff, P. N.

    Fan engineering and compression machines are discussed. Basic aspects of fan performance and design are reviewed, and the design and performance characteristics of radial-flow fans, axial-flow fans, and controllable pitch fans are examined in detail. Air-conditioning systems are discussed, and noise, vibration, and mechanical considerations in fans are extensively examined. The thermodynamic principles governing compression machines are reviewed, and piston compressors, rotary compressors, blowers, and centrifugal compressors are discussed.

  10. Development of guidelines for improved hydraulic design of waste stabilisation ponds.

    PubMed

    Shilton, A; Harrison, J

    2003-01-01

    Pond hydraulic behaviour is influenced by the inlet/outlet configuration, baffles and wind, but design information relating to these factors is still very limited. This paper reviews the development of "Guidelines for the Improved Hydraulic Design of Waste Stabilisation Ponds" and summarises some of the key findings and recommendations. This work was based on review of previous research, laboratory experimentation, field studies and mathematical modelling using computational fluid dynamics. The inlet design can have a significant influence on the flow regime in a pond. Poorly considered positioning of the inlet and the outlet can create hydraulic short-circuiting problems. As an example of the nature of the work undertaken in this project, the use of a small horizontal inlet pipe was compared against a vertical inlet design. A practical method of assessing the relative significance of wind versus inlet power input was presented. The application of this analysis may allow engineers to size inlet pipes to help control the flow patterns in ponds for efficient performance. Extensive testing has been undertaken on a wide range of baffle configurations. An example of this research showed how short stub baffles could provide similar improvements to longer "traditional" baffle designs, potentially offering significant savings in construction costs. For traditional baffle designs a minimum of two baffles is recommended. For the pond modelled in this work, it was found that any more than four baffles gave only marginal improvements. PMID:14510208

  11. A novel design of semi-active hydraulic mount with wide-band tunable notch frequency

    NASA Astrophysics Data System (ADS)

    Wang, Min; Yao, Guo-feng; Zhao, Jing-zhou; Qin, Min

    2014-04-01

    Hydraulic engine mount is advanced vibration isolator with superior performance to reduce vibration transferred from engine to chassis. As the stiffness at notch frequency is small, some semi-active or active hydraulic mounts tune some parameters to let notch frequency coincide with exciting frequency for better vibration isolation performance. It is discovered the current semi-active mounts can tune the notch frequency in narrow frequency band when only one parameter is tuned. A novel semi-active hydraulic engine mount design which introduces screw thread is proposed and researched in the paper. This hydraulic mount can control both cross section area and the length of inertia track and the theoretical tunable notch frequency band is [0, ∞). Theoretical work is carried out to uncover the capability for the proposed design to tune notch frequency. Simulation work is performed to understand its high vibration isolation performance. For the purpose of energy conservation, the friction self-locking is introduced. This denotes once the mount is tuned at optimal condition, the energy can be cut off and the optimal condition will never change. We also determine the best time to tune the parameters of the proposed mount in order to decrease the acting force. The proposed semi-active mount has capability to obtain wide band tunable notch frequency and has merit of energy conservation.

  12. Tribology of hydraulic pumps

    SciTech Connect

    Yamaguchi, A.

    1997-12-31

    To obtain much higher performance than that of alternative power transmission systems, hydraulic systems have been continuously evolving to use high-pressure. Adoption of positive displacement pumps and motors is based on this reason. Therefore, tribology is a key terminology for hydraulic pumps and motors to obtain excellent performance and durability. In this paper the following topics are investigated: (1) the special feature of tribology of hydraulic pumps and motors; (2) indication of the important bearing/sealing parts in piston pumps and effects of the frictional force and leakage flow to performance; (3) the methods to break through the tribological limitation of hydraulic equipment; and (4) optimum design of the bearing/sealing parts used in the fluid to mixed lubrication regions.

  13. Designing attractive gamification features for collaborative storytelling websites.

    PubMed

    Hsu, Shang Hwa; Chang, Jen-Wei; Lee, Chun-Chia

    2013-06-01

    Gamification design is considered as the predictor of collaborative storytelling websites' success. Although aforementioned studies have mentioned a broad range of factors that may influence gamification, they neither depicted the actual design features nor relative attractiveness among them. This study aims to identify attractive gamification features for collaborative storytelling websites. We first constructed a hierarchical system structure of gamification design of collaborative storytelling websites and conducted a focus group interview with eighteen frequent users to identify 35gamification features. After that, this study determined the relative attractiveness of these gamification features by administrating an online survey to 6333 collaborative storytelling websites users. The results indicated that the top 10 most attractive gamification features could account for more than 50% of attractiveness among these 35 gamification features. The feature of unpredictable time pressure is important to website users, yet not revealed in previous relevant studies. Implications of the findings were discussed. PMID:23438264

  14. 21 CFR 211.42 - Design and construction features.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Design and construction features. 211.42 Section... § 211.42 Design and construction features. (a) Any building or buildings used in the manufacture... sampling, testing, or examination by the quality control unit before release for manufacturing or...

  15. Hydraulic features of Engineered Log Jams (ELJs) and their influence on salmonid behavior

    NASA Astrophysics Data System (ADS)

    Rice, W. D.; Fetter, D.; Somerville, G.; Tullos, D. D.; Palacijo, J.

    2010-12-01

    In an effort to recreate channel complexity and habitat, construction of Engineered Log Jams (ELJs) is increasing, yet questions remain regarding their effectiveness due to lack of observations of hydraulics and fish use around these structures. To address this limitation, we surveyed four different forms of engineered log jams in western Oregon. The structures and near-structure stream environments were surveyed for bathymetry, instrumented with an Acoustic Doppler Stream Profiler (ADCP) to measure velocities, and snorkeled to observe the behavior of salmonids. Further, tensor visualization of stream velocities were constructed to investigate circulation and flow patterns in and around the ELJ structures. We found that more complex structures created a more varied bottom profile, while simpler structures resulted in more simple pools. However, all log jams did increase the diversity of flow patterns, with areas of high and low velocity that appeared to influence fish behavior. Variation in the size of salmonids was related to greater variation in the velocity, and fish behavior (feeding, aggression) was observed to vary within the pools. Our results provide preliminary evidence of the influence of engineered structures on the diversity and versatility of fish habitat.

  16. HYDRAULIC SERVO

    DOEpatents

    Wiegand, D.E.

    1962-05-01

    A hydraulic servo is designed in which a small pressure difference produced at two orifices by an electrically operated flapper arm in a constantly flowing hydraulic loop is hydraulically amplified by two constant flow pumps, two additional orifices, and three unconnected ball pistons. Two of the pistons are of one size and operate against the additional orifices, and the third piston is of a different size and operates between and against the first two pistons. (AEC)

  17. Lead Coolant Test Facility Systems Design, Thermal Hydraulic Analysis and Cost Estimate

    SciTech Connect

    Soli Khericha; Edwin Harvego; John Svoboda; Ryan Dalling

    2012-01-01

    The Idaho National Laboratory prepared a preliminary technical and functional requirements (T&FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead-bismuth eutectic coolant. Based on review of current world lead or lead-bismuth test facilities and research needs listed in the Generation IV Roadmap, five broad areas of requirements were identified as listed: (1) Develop and Demonstrate Feasibility of Submerged Heat Exchanger; (2) Develop and Demonstrate Open-lattice Flow in Electrically Heated Core; (3) Develop and Demonstrate Chemistry Control; (4) Demonstrate Safe Operation; and (5) Provision for Future Testing. This paper discusses the preliminary design of systems, thermal hydraulic analysis, and simplified cost estimate. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200 C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

  18. Optimizing hydraulic fracture design in the diatomite formation, Lost Hills Field

    SciTech Connect

    Nelson, D.G.; Klins, M.A.; Manrique, J.F.

    1996-12-31

    Since 1988, over 1.3 billion pounds of proppant have been placed in the Lost Hills Field of Kern County. California in over 2700 hydraulic fracture treatments involving investments of about $150 million. In 1995, systematic reevaluation of the standard, field trial-based fracture design began. Reservoir, geomechanical, and hydraulic fracture characterization; production and fracture modeling; sensitivity analysis; and field test results were integrated to optimize designs with regard to proppant volume, proppant ramps, and perforating strategy. The results support a reduction in proppant volume from 2500 to 1700 lb/ft which will save about $50,000 per well, totalling over $3 million per year. Vertical coverage was found to be a key component of fracture quality which could be optimized by eliminating perforations from lower stress intervals, reducing the total number of perforations, and reducing peak slurry loading from 16 to 12 ppa. A relationship between variations in lithology, pore pressure, and stress was observed. Point-source, perforating strategies were investigated and variable multiple fracture behavior was observed. The discussed approach has application in areas where stresses are variable; pay zones are thick; hydraulic fracture design is based primarily on empirical, trial-and-error field test results; and effective, robust predictive models involving real-data feedback have not been incorporated into the design improvement process.

  19. Thermal-hydraulic criteria for the APT tungsten neutron source design

    SciTech Connect

    Pasamehmetoglu, K.

    1998-03-01

    This report presents the thermal-hydraulic design criteria (THDC) developed for the tungsten neutron source (TNS). The THDC are developed for the normal operations, operational transients, and design-basis accidents. The requirements of the safety analyses are incorporated into the design criteria, consistent with the integrated safety management and the safety-by-design philosophy implemented throughout the APT design process. The phenomenology limiting the thermal-hydraulic design and the confidence level requirements for each limit are discussed. The overall philosophy of the uncertainty analyses and the confidence level requirements also are presented. Different sets of criteria are developed for normal operations, operational transients, anticipated accidents, unlikely accidents, extremely unlikely accidents, and accidents during TNS replacement. In general, the philosophy is to use the strictest criteria for the high-frequency events. The criteria is relaxed as the event frequencies become smaller. The THDC must be considered as a guide for the design philosophy and not as a hard limit. When achievable, design margins greater than those required by the THDC must be used. However, if a specific event sequence cannot meet the THDC, expensive design changes are not necessary if the single event sequence results in sufficient margin to safety criteria and does not challenge the plant availability or investment protection considerations.

  20. Thermal-hydraulic design of the target/blanket for the accelerator production of tritium conceptual design

    SciTech Connect

    Willcutt, G.J.E. Jr.; Kapernick, R.J.

    1997-11-01

    A conceptual design was developed for the target/blanket system of an accelerator-based system to produce tritium. The target/blanket system uses clad tungsten rods for a spallation target and clad lead rods as a neutron multiplier in a blanket surrounding the target. The neutrons produce tritium in {sup 3}He, which is contained in aluminum tubes located in the decoupler and blanket regions. This paper presents the thermal-hydraulic design of the target, decoupler, and blanket developed for the conceptual design of the Accelerator Production of Tritium Project, and demonstrates there is adequate margin in the design at full power operation.

  1. Effects of radial diffuser hydraulic design on a double-suction centrifugal pump

    NASA Astrophysics Data System (ADS)

    Hou, H. C.; Zhang, Y. X.; Xu, C.; Zhang, J. Y.; Li, Z. L.

    2016-05-01

    In order to study effects of radial diffuser on hydraulic performance of crude oil pump, the steady CFD numerical method is applied and one large double-suction oil pump running in long-distance pipeline is considered. The research focuses on analysing the influence of its diffuser vane profile on hydraulic performance of oil pump. The four different types of cylindrical vane have been designed by in-house codes mainly including double arcs (DA), triple arcs (TA), equiangular spiral line (ES) and linear variable angle spiral line (LVS). During design process diffuser vane angles at inlet and outlet are tentatively given within a certain range and then the wrapping angle of the four types of diffuser vanes can be calculated automatically. Under the given inlet and outlet angles, the linear variable angle spiral line profile has the biggest wrapping angle and profile length which is good to delay channel diffusion but bring more friction hydraulic loss. Finally the vane camber line is thickened at the certain uniform thickness distribution and the 3D diffuser models are generated. The whole flow passage of oil pump with different types of diffusers under various flow rate conditions are numerically simulated based on RNG k-ɛ turbulent model and SIMPLEC algorithm. The numerical results show that different types of diffusers can bring about great difference on the hydraulic performance of oil pump, of which the ES profile diffuser with its proper setting angle shows the best hydraulic performance and its inner flow field is improved obviously. Compared with the head data from model sample, all designed diffusers can make a certain improvement on head characteristic. At the large flow rate conditions the hydraulic efficiency increases obviously and the best efficiency point shift to the large flow rate range. The ES profile diffuser embodies the better advantages on pump performance which can be explained theoretically that the diffuser actually acts as a diffusion

  2. Experiences with the hydraulic design of the high specific speed Francis turbine

    NASA Astrophysics Data System (ADS)

    Obrovsky, J.; Zouhar, J.

    2014-03-01

    The high specific speed Francis turbine is still suitable alternative for refurbishment of older hydro power plants with lower heads and worse cavitation conditions. In the paper the design process of such kind of turbine together with the results comparison of homological model tests performed in hydraulic laboratory of ČKD Blansko Engineering is introduced. The turbine runner was designed using the optimization algorithm and considering the high specific speed hydraulic profile. It means that hydraulic profiles of the spiral case, the distributor and the draft tube were used from a Kaplan turbine. The optimization was done as the automatic cycle and was based on a simplex optimization method as well as on a genetic algorithm. The number of blades is shown as the parameter which changes the resulting specific speed of the turbine between ns=425 to 455 together with the cavitation characteristics. Minimizing of cavitation on the blade surface as well as on the inlet edge of the runner blade was taken into account during the design process. The results of CFD analyses as well as the model tests are mentioned in the paper.

  3. A Bayesian Chance-Constrained Method for Hydraulic Barrier Design Under Model Structure Uncertainty

    NASA Astrophysics Data System (ADS)

    Chitsazan, N.; Pham, H. V.; Tsai, F. T. C.

    2014-12-01

    The groundwater community has widely recognized the model structure uncertainty as the major source of model uncertainty in groundwater modeling. Previous studies in the aquifer remediation design, however, rarely discuss the impact of the model structure uncertainty. This study combines the chance-constrained (CC) programming with the Bayesian model averaging (BMA) as a BMA-CC framework to assess the effect of model structure uncertainty in the remediation design. To investigate the impact of the model structure uncertainty on the remediation design, we compare the BMA-CC method with the traditional CC programming that only considers the model parameter uncertainty. The BMA-CC method is employed to design a hydraulic barrier to protect public supply wells of the Government St. pump station from saltwater intrusion in the "1,500-foot" sand and the "1-700-foot" sand of the Baton Rouge area, southeastern Louisiana. To address the model structure uncertainty, we develop three conceptual groundwater models based on three different hydrostratigraphy structures. The results show that using the traditional CC programming overestimates design reliability. The results also show that at least five additional connector wells are needed to achieve more than 90% design reliability level. The total amount of injected water from connector wells is higher than the total pumpage of the protected public supply wells. While reducing injection rate can be achieved by reducing reliability level, the study finds that the hydraulic barrier design to protect the Government St. pump station is not economically attractive.

  4. Bayesian Chance-Constrained Hydraulic Barrier Design under Geological Structure Uncertainty.

    PubMed

    Chitsazan, Nima; Pham, Hai V; Tsai, Frank T-C

    2015-01-01

    The groundwater community has widely recognized geological structure uncertainty as a major source of model structure uncertainty. Previous studies in aquifer remediation design, however, rarely discuss the impact of geological structure uncertainty. This study combines chance-constrained (CC) programming with Bayesian model averaging (BMA) as a BMA-CC framework to assess the impact of geological structure uncertainty in remediation design. To pursue this goal, the BMA-CC method is compared with traditional CC programming that only considers model parameter uncertainty. The BMA-CC method is employed to design a hydraulic barrier to protect public supply wells of the Government St. pump station from salt water intrusion in the "1500-foot" sand and the "1700-foot" sand of the Baton Rouge area, southeastern Louisiana. To address geological structure uncertainty, three groundwater models based on three different hydrostratigraphic architectures are developed. The results show that using traditional CC programming overestimates design reliability. The results also show that at least five additional connector wells are needed to achieve more than 90% design reliability level. The total amount of injected water from the connector wells is higher than the total pumpage of the protected public supply wells. While reducing the injection rate can be achieved by reducing the reliability level, the study finds that the hydraulic barrier design to protect the Government St. pump station may not be economically attractive. PMID:25510348

  5. Design and control of a high velocity, high force hydraulic shock test machine

    NASA Astrophysics Data System (ADS)

    Favour, J. D.

    1986-04-01

    This paper discusses the design and control of a large hydraulic shock testing device. The system is capable of peak velocities up to 10.2 m/s (400 in/sec) and peak forces up to 801 kN (180,000 lbs). The major challenges discussed are: (1) the concept design, (2) the specification and procurement of two very large (2500 gpm) electrohydraulic servovalves and (3) the failsafe control of the servovalves and system response. The system performance is briefly discussed.

  6. Critical Features of Engineering Design in Technology Education

    ERIC Educational Resources Information Center

    Asunda, Paul A.; Hill, Roger B.

    2007-01-01

    The purpose of this study was to find critical features of engineering design that can be incorporated within technology education learning activities, and develop a rubric for assessing these features. Data were collected through semi-structured interviews with three professors actively involved in engineering education. Supporting documents such…

  7. Design Concept for Garbage Bin with Situation Awareness Feature

    NASA Astrophysics Data System (ADS)

    Supattatham, Montri; Papasratorn, Borworn

    Many measures to prevent wide-spread of communicable diseases depends on embedded IT into objects found in public places. This makes it possible to have objects with awareness on surrounding environment, or having situation awareness. This paper presents design concept to add situation awareness features to automatic garbage bin. There are three design levels for including situation awareness features with garbage bin. From awareness goals, required features are identified. Perception, comprehension, and projection are then aligned with the required features, in order to have desired awareness. Automatic garbage bin is implemented using design specification from the proposed design concept. Result from convenience sampling survey reveals that users are satisfied with the implemented garbage bin.

  8. Design of a miniature hydraulic compression load frame for microdiffraction tests at the Advanced Photon Source.

    SciTech Connect

    Shu, D.; Varma, R.; Krasnicki, S.; Sinha, S.

    1999-10-11

    In support of the x-ray synchrotrons radiation multidiffraction project of Los Alamos National Laboratory at the Advanced Photon Source (APS), we have designed and fabricated a miniature hydraulic compression load frame with 20000 N load capacity for metal specimen tests at the APS. The compact design allows the load frame to sit on the center of a 6-circle goniometer with six degrees of freedom and maximum solid angle accessibility for the incoming x-ray beam and diffraction beam detectors. A set of compact precision stages with submicron resolution has been designed for the load frame positioning to compensate the sample internal elastic and/or plastic deformation during the loading process. The system design, specifications, and test results are presented.

  9. Design of a hydraulic power take-off system for the wave energy device with an inverse pendulum

    NASA Astrophysics Data System (ADS)

    Zhang, Da-hai; Li, Wei; Zhao, Hai-tao; Bao, Jing-wei; Lin, Yong-gang

    2014-04-01

    This paper describes a dual-stroke acting hydraulic power take-off (PTO) system employed in the wave energy converter (WEC) with an inverse pendulum. The hydraulic PTO converts slow irregular reciprocating wave motions to relatively smooth, fast rotation of an electrical generator. The design of the hydraulic PTO system and its control are critical to maximize the generated power. A time domain simulation study and the laboratory experiment of the full-scale beach test are presented. The results of the simulation and laboratory experiments including their comparison at full-scale are also presented, which have validated the rationality of the design and the reliability of some key components of the prototype of the WEC with an inverse pendulum with the dual-stroke acting hydraulic PTO system.

  10. Fast SIFT design for real-time visual feature extraction.

    PubMed

    Chiu, Liang-Chi; Chang, Tian-Sheuan; Chen, Jiun-Yen; Chang, Nelson Yen-Chung

    2013-08-01

    Visual feature extraction with scale invariant feature transform (SIFT) is widely used for object recognition. However, its real-time implementation suffers from long latency, heavy computation, and high memory storage because of its frame level computation with iterated Gaussian blur operations. Thus, this paper proposes a layer parallel SIFT (LPSIFT) with integral image, and its parallel hardware design with an on-the-fly feature extraction flow for real-time application needs. Compared with the original SIFT algorithm, the proposed approach reduces the computational amount by 90% and memory usage by 95%. The final implementation uses 580-K gate count with 90-nm CMOS technology, and offers 6000 feature points/frame for VGA images at 30 frames/s and ∼ 2000 feature points/frame for 1920 × 1080 images at 30 frames/s at the clock rate of 100 MHz. PMID:23743775

  11. Structural health monitoring feature design by genetic programming

    NASA Astrophysics Data System (ADS)

    Harvey, Dustin Y.; Todd, Michael D.

    2014-09-01

    Structural health monitoring (SHM) systems provide real-time damage and performance information for civil, aerospace, and other high-capital or life-safety critical structures. Conventional data processing involves pre-processing and extraction of low-dimensional features from in situ time series measurements. The features are then input to a statistical pattern recognition algorithm to perform the relevant classification or regression task necessary to facilitate decisions by the SHM system. Traditional design of signal processing and feature extraction algorithms can be an expensive and time-consuming process requiring extensive system knowledge and domain expertise. Genetic programming, a heuristic program search method from evolutionary computation, was recently adapted by the authors to perform automated, data-driven design of signal processing and feature extraction algorithms for statistical pattern recognition applications. The proposed method, called Autofead, is particularly suitable to handle the challenges inherent in algorithm design for SHM problems where the manifestation of damage in structural response measurements is often unclear or unknown. Autofead mines a training database of response measurements to discover information-rich features specific to the problem at hand. This study provides experimental validation on three SHM applications including ultrasonic damage detection, bearing damage classification for rotating machinery, and vibration-based structural health monitoring. Performance comparisons with common feature choices for each problem area are provided demonstrating the versatility of Autofead to produce significant algorithm improvements on a wide range of problems.

  12. The design of an electro-hydraulically controlled, manual transmission for a hybrid electric vehicle

    SciTech Connect

    Davis, G.W.; Hoff, C.J.

    1998-07-01

    An electro-hydraulically controlled, manual transmission has been developed for the Department of Energy's FutureCar Challenge. This project which is jointly sponsored by the DOE and the Partnership for a New Generation of Vehicles (PNGV) seeks to modify a production mid-size car to reach 80 mpg, yet still maintain the safety and consumer acceptability of the original vehicle. To meet this challenge, a 1996 Ford Taurus has been modified into a parallel drive, hybrid electric vehicle. The propulsion system of this vehicle is based on a DC electric motor, which is coupled via a belt drive, in parallel, with a 1.9 liter turbo-charged, direct injection diesel engine. Both propulsion units are then coupled to the transmission. The OEM automatic transmission has been replaced with a five-speed, manual transmission, which was adapted from an earlier model year production Taurus SHO vehicle. This transmission is both lighter and more mechanically efficient than the automatic transmission. In order to provide the automatic transmission shifting capabilities expected by the consumer for a vehicle of this size, an electro-hydraulic control unit was designed and built. This unit automatically engages the clutch and shifts gears as required during vehicle operation. Gear selection is controlled by a programmable logic controller (PLC), which utilizes throttle and vehicle speed input signals. Additionally, the driver may select gears using a modified steering-column PRNDL selector. This paper discusses the final design of this system and provides an evaluation of its performance.

  13. Innovation in Aerodynamic Design Features of Soviet Missiles

    NASA Technical Reports Server (NTRS)

    Spearman, M. Leroy

    2006-01-01

    Wind tunnel investigations of some tactical and strategic missile systems developed by the former Soviet Union have been included in the basic missile research programs of the NACA/NASA. Studies of the Soviet missiles sometimes revealed innovative design features that resulted in unusual or unexpected aerodynamic characteristics. In some cases these characteristics have been such that the measured performance of the missile exceeds what might have been predicted. In other cases some unusual design features have been found that would alleviate what might otherwise have been a serious aerodynamic problem. In some designs, what has appeared to be a lack of refinement has proven to be a matter of expediency. It is a purpose of this paper to describe some examples of unusual design features of some Soviet missiles and to illustrate the effectiveness of the design features on the aerodynamic behavior of the missile. The paper draws on the experience of the author who for over 60 years was involved in the aerodynamic wind tunnel testing of aircraft and missiles with the NACA/NASA.

  14. Spectral feature design in high dimensional multispectral data

    NASA Technical Reports Server (NTRS)

    Chen, Chih-Chien Thomas; Landgrebe, David A.

    1988-01-01

    The High resolution Imaging Spectrometer (HIRIS) is designed to acquire images simultaneously in 192 spectral bands in the 0.4 to 2.5 micrometers wavelength region. It will make possible the collection of essentially continuous reflectance spectra at a spectral resolution sufficient to extract significantly enhanced amounts of information from return signals as compared to existing systems. The advantages of such high dimensional data come at a cost of increased system and data complexity. For example, since the finer the spectral resolution, the higher the data rate, it becomes impractical to design the sensor to be operated continuously. It is essential to find new ways to preprocess the data which reduce the data rate while at the same time maintaining the information content of the high dimensional signal produced. Four spectral feature design techniques are developed from the Weighted Karhunen-Loeve Transforms: (1) non-overlapping band feature selection algorithm; (2) overlapping band feature selection algorithm; (3) Walsh function approach; and (4) infinite clipped optimal function approach. The infinite clipped optimal function approach is chosen since the features are easiest to find and their classification performance is the best. After the preprocessed data has been received at the ground station, canonical analysis is further used to find the best set of features under the criterion that maximal class separability is achieved. Both 100 dimensional vegetation data and 200 dimensional soil data were used to test the spectral feature design system. It was shown that the infinite clipped versions of the first 16 optimal features had excellent classification performance. The overall probability of correct classification is over 90 percent while providing for a reduced downlink data rate by a factor of 10.

  15. Quasi-three dimensional hydraulic design and performance calculation of high specific speed mixed-flow pump

    NASA Astrophysics Data System (ADS)

    Su, M.; Zhang, Y. X.; Zhang, J. Y.; Hou, H. C.

    2016-05-01

    According to the basic parameters of 211-80 high specific speed mixed-flow pump, based on the quasi-three dimensional flow theory, the hydraulic design of impeller and its matching spaced guide vanes for high specific speed mixed flow pump was completed, in which the iterative calculation of S 1, S 2 stream surfaces was employed to obtain meridional flow fields and the point-by-point integration method was employed to draw blade camber lines. Blades are thickened as well as blade leading edges are smoothed in the conformal mapping surface. Subsequently the internal fields of the whole flow passage of the designed pump were simulated by using RANS equations with RNG k-ε two-equation turbulent model. The results show that, compared with the 211-80 model, the hydraulic efficiency of the designed pump at the optimal flow rate increases 9.1%. The hydraulic efficiency of designed pump in low flow rate condition (78% designed flow rate) increases 6.46%. The hydraulic efficiency in high flow rate areas increases obviously and there is no bad phenomenon of suddenly decrease of hydraulic efficiency in model pump. From the distributions of velocity and pressure fields, it can be seen that the flow in impeller is uniform and the increase of pressure is gentle. There are no obvious impact phenomenon on impeller inlet and obvious wake shedding vortex phenomenon from impeller outlet to guide vanes inlet.

  16. Multi-Function Waste Tank Facility thermal hydraulic analysis for Title II design

    SciTech Connect

    Cramer, E.R.

    1994-11-10

    The purpose of this work was to provide the thermal hydraulic analysis for the Multi-Function Waste Tank Facility (MWTF) Title II design. Temperature distributions throughout the tank structure were calculated for subsequent use in the structural analysis and in the safety evaluation. Calculated temperatures of critical areas were compared to design allowables. Expected operating parameters were calculated for use in the ventilation system design and in the environmental impact documentation. The design requirements were obtained from the MWTF Functional Design Criteria (FDC). The most restrictive temperature limit given in the FDC is the 200 limit for the haunch and dome steel and concrete. The temperature limit for the rest of the primary and secondary tanks and concrete base mat and supporting pad is 250 F. Also, the waste should not be allowed to boil. The tank geometry was taken from ICF Kaiser Engineers Hanford drawing ES-W236A-Z1, Revision 1, included here in Appendix B. Heat removal rates by evaporation from the waste surface were obtained from experimental data. It is concluded that the MWTF tank cooling system will meet the design temperature limits for the design heat load of 700,000 Btu/h, even if cooling flow is lost to the annulus region, and temperatures change very slowly during transients due to the high heat capacity of the tank structure and the waste. Accordingly, transients will not be a significant operational problem from the viewpoint of meeting the specified temperature limits.

  17. Hydraulic design, numerical simulation and BVF diagnosis of high efficiency centrifugal pump

    NASA Astrophysics Data System (ADS)

    Zhang, Y. X.; Chen, L.; Zhou, X.; Jiangand, C. W.; Su, M.

    2012-11-01

    Under the Two-dimensional Flow Theory and the Velocity Coefficient Theory, a centrifugal-pump impeller has been designed, based on the parameters of IS150-125-250 centrifugal pump. And self-compiled programs have been used to complete the hydraulic design of the whole flow passage of centrifugal pump. The space bending and twisting characteristics of the design blade are more obvious. Then, numerical simulation is applied to the inner flow field of the two pumps using RANS (Reynolds Averaged N-S) Equation with a standard k-ε two-equation turbulence model. The compare of the numerical simulation data of two centrifugal pumps, getting from 13 working points including design condition, shows that, the design pump has higher head and efficiency in the range of lower flow rate. Based on the numerical results of the inner flow of the design pump and model pump, the boundary vorticity flux (BVF) diagnostics has been used to analyze the BVF distribution of suction surface and pressure surface of two pumps. The result shows that, the BVF distribution of the design pump is more uniform and smooth, with smaller peak value.

  18. View of landscape design feature in Hinkley Square. Note reconstructed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of landscape design feature in Hinkley Square. Note reconstructed Easter Hill Building No. 2 on left and Building No. 3 on right. Looking north - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  19. View of Hinkley Square. Note boulders as landscape design features ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Hinkley Square. Note boulders as landscape design features and reconstructed Easter Hill Building No. 2 on left and Building No. 3 on right. Looking north - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  20. View of designed landscape features between Buildings No. 8 and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of designed landscape features between Buildings No. 8 and 10 at Parking Area No. 8. Note placement of boulders and staircase to Building No. 32 at rear. Looking north - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  1. View of hillside and designed landscape features between Buildings No. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of hillside and designed landscape features between Buildings No. 32, 33, and 19 from left to right. Looking northeast - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  2. View of designed landscape features between Buildings No. 8, at ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of designed landscape features between Buildings No. 8, at left, and 10. Note staircase to Building No. 32 at rear. Looking north - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  3. 21 CFR 211.42 - Design and construction features.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Design and construction features. 211.42 Section 211.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Buildings and...

  4. 21 CFR 211.42 - Design and construction features.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Design and construction features. 211.42 Section 211.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Buildings and...

  5. 21 CFR 211.42 - Design and construction features.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Design and construction features. 211.42 Section 211.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Buildings and...

  6. 21 CFR 211.42 - Design and construction features.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Design and construction features. 211.42 Section 211.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Buildings and...

  7. Design of a Magnetostrictive-Hydraulic Actuator Considering Nonlinear System Dynamics and Fluid-Structure Coupling

    NASA Astrophysics Data System (ADS)

    Larson, John Philip

    Smart material electro-hydraulic actuators (EHAs) utilize fluid rectification via one-way check valves to amplify the small, high-frequency vibrations of certain smart materials into large motions of a hydraulic cylinder. Although the concept has been demonstrated in previously, the operating frequency of smart material EHA systems has been limited to a small fraction of the available bandwidth of the driver materials. The focus of this work is to characterize and model the mechanical performance of a magnetostrictive EHA considering key system components: rectification valves, smart material driver, and fluid-system components, leading to an improved actuator design relative to prior work. The one-way valves were modeled using 3-D finite element analysis, and their behavior was characterized experimentally by static and dynamic experimental measurement. Taking into account the effect of the fluid and mechanical conditions applied to the valves within the pump, the dynamic response of the valve was quantified and applied to determine rectification bandwidth of different valve configurations. A novel miniature reed valve, designed for a frequency response above 10~kHz, was fabricated and tested within a magnetostrictive EHA. The nonlinear response of the magnetostrictive driver, including saturation and hysteresis effects, was modeled using the Jiles-Atherton approach to calculate the magnetization and the resulting magnetostriction based on the applied field calculated within the rod from Maxwell's equations. The dynamic pressure response of the fluid system components (pumping chamber, hydraulic cylinder, and connecting passages) was measured over a range of input frequencies. For the magnetostrictive EHA tested, the peak performance frequency was found to be limited by the fluid resonances within the system. A lumped-parameter modeling approach was applied to model the overall behavior of a magnetostrictive EHA, incorporating models for the reed valve response

  8. Settling basin design in a constructed wetland using TSS removal efficiency and hydraulic retention time.

    PubMed

    Lee, Soyoung; Maniquiz-Redillas, Marla C; Kim, Lee-Hyung

    2014-09-01

    Using total suspended solid (TSS) removal efficiency and hydraulic retention time (HRT) as design parameters a design guideline of a settling basin in a constructed wetland (CW) was suggested; as well as management of sediment and particle in the settling basin. The CW was designed to treat the piggery wastewater effluent from a wastewater treatment plant during dry days and stormwater runoff from the surrounding paved area during wet days. The first settling basin (FSB) in the CW was theoretically designed with a total storage volume (TSV) of 453m(3) and HRT of 5.5hr. The amount of sediment and particles settled at the FSB was high due to the sedimentation and interception of plants in the CW. Dredging of sediments was performed when the retention rate at the FSB decreased to approximately 80%. Findings showed that the mean flow rate was 21.8m(3)/hr less than the designed flow rate of 82.8m(3)/hr indicating that the FSB was oversize and operated with longer HRT (20.7hr) compared to the design HRT. An empirical model to estimate the length of the settling basin in the CW was developed as a function of HRT and desired TSS removal efficiency. Using the minimum tolerable TSS removal efficiency of 30%, the length of the FSB was estimated to be 31.2m with 11.8hr HRT. PMID:25193826

  9. Conceptual design and thermal-hydraulic characteristics of natural circulation Boiling Water Reactors

    SciTech Connect

    Kataoka, Y.; Suzuki, H.; Murase, M. ); Horiuchi, T.; Miki, M. )

    1988-08-01

    A natural circulation boiling water reactor (BWR) with a rated capacity of 600 MW (electric) has been conceptually designed for small- and medium-sized light water reactors. The components and systems in the reactor are simplified by eliminating pumped recirculation systems and pumped emergency core cooling systems. Consequently, the volume of the reactor building is -- 50% of that for current BWRs with the same rated capacity; the construction period is also shorter. Its thermal-hydraulic characteristics, critical power ratio (CPR) and flow stability at steady state, decrease in the minimum CPR (..delta..MCPR) at transients, and the two-phase mixture level in the reactor pressure vessel (RPV) during accidents are investigated. The two-phase mixture level in the RPV during an accident does not decrease to lower than the top of the core; the core uncovery and heatup of fuel cladding would not occur during any loss-of-coolant accident.

  10. Thermal-hydraulics for space power, propulsion, and thermal management system design

    SciTech Connect

    Krotiuk, W.J.

    1990-01-01

    The present volume discusses thermal-hydraulic aspects of current space projects, Space Station thermal management systems, the thermal design of the Space Station Free-Flying Platforms, the SP-100 Space Reactor Power System, advanced multi-MW space nuclear power concepts, chemical and electric propulsion systems, and such aspects of the Space Station two-phase thermal management system as its mechanical pumped loop and its capillary pumped loop's supporting technology. Also discussed are the startup thaw concept for the SP-100 Space Reactor Power System, calculational methods and experimental data for microgravity conditions, an isothermal gas-liquid flow at reduced gravity, low-gravity flow boiling, computations of Space Shuttle high pressure cryogenic turbopump ball bearing two-phase coolant flow, and reduced-gravity condensation.

  11. The design concept of the 6-degree-of-freedom hydraulic shaker at ESTEC

    NASA Technical Reports Server (NTRS)

    Brinkman, P. W.; Kretz, D.

    1992-01-01

    The European Space Agency (ESA) has decided to extend its test facilities at the European Space and Technology Center (ESTEC) at Noordwijk, The Netherlands, by implementing a 6-degree-of-freedom hydraulic shaker. This shaker will permit vibration testing of large payloads in the frequency range from 0.1 Hz to 100 Hz. Conventional single axis sine and random vibration modes can be applied without the need for a configuration change of the test set-up for vertical and lateral excitations. Transients occurring during launch and/or landing of space vehicles can be accurately simulated in 6-degrees-of-freedom. The performance requirements of the shaker are outlined and the results of the various trade-offs, which are investigated during the initial phase of the design and engineering program are provided. Finally, the resulting baseline concept and the anticipated implementation plan of the new test facility are presented.

  12. Design, manufacture and evaluation of a hydraulically installed, multi-sampling lysimeter. Final report

    SciTech Connect

    Scroppo, J.A.; Scroppo, G.L.; Carty, R.H.; Chaimberg, M.; Timmons, R.D.; O`Donnell, M.

    1992-06-01

    There is a need for a quick, simple, reliable, and inexpensive on-site method for sampling soil pollutants before they reach the groundwater. Vadose zone monitoring is an important aspect of sound groundwater management. In the vadose zone, where water moves via percolation, this water medium possesses the ability to transfer hazardous wastes to the nation`s groundwater system. Obtaining samples of moisture and contaminants from the vadose zone is necessary if potential problems are to be identified before they reach the water table. Accurate determination of spatial distribution, movement, and concentrations of contaminants is essential to the selection of remediation technologies. There is a need for three-dimentional subsurface characterization technologies to identify the location of hazardous plumes and their migration. Current subsurface characterization methods for dispersed contaminants primarily involve a time consuming, expensive process for drilling wells and taking samples. With no major water flow in the vadose zone, conventional monitoring wells will not function as designed. The multi-sampling lysimeter can be readily linked with physical and chemical sensors for on-site screening. The hydraulically-installed suction lysimeter was capable of extracting soil pore liquid samples from unsaturated test soils without the need to predrill a well. Test results verified that the lysimeters installed with a hydraulic or mechanical ram were able to collect soil pore liquid samples in excess of the amount typically required for monitoring and analysis on a daily basis. Modifications to the prototype design eliminated moving parts and the need for inflatable packers. The elimination of the packer system and the use of porous nickel contributed to increased system ruggedness.

  13. View of designed landscape features between Buildings No. 8 and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of designed landscape features between Buildings No. 8 and 10. Note placement of boulders at rear, staircase in foreground is seen in HABS CA-2783-39. Building No. 10 on left and Building No. 8 on right. Looking south - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  14. Cost effectiveness of operator features in equipment design.

    PubMed

    Williams, J C

    1983-06-01

    In design negotiation, the attribution of credible values to the incorporation or deletion of operator features allows engineers the freedom to judge the overall effect of human factors recommendations in relation to the achievement of a design specification. Likewise in the development phase, product planners frequently need more precise statements about productivity, training needs and general operational performance than, "it will be greater/less, worse/better than...". The method described utilises measured and synthetic data, learning theory and Markov processes to calculate the likelihood of operator task failure. These failure rates are then treated via filter factors derived from the application of the Nominal Groups Technique to give a global statement of the likelihood of operator failure resulting in unscheduled calls for service. Using the relationship between the cost of service calls and the overall life cost of developing, manufacturing, marketing and supporting a leased product, it is then possible to place credible values on the design features in question. Thus during the design process it becomes feasible to calculate the likely effects of human factors recommendations and modifications in relation to manufacturing costs, and thereby facilitate rational assessment of their implementation on a sound economic basis. This technique has been used to considerable effect, and represents a useful additional tool for the human factors practitioner in the design negotiation process. Further developments and refinements are planned, and it is anticipated that a similar technique will shortly be available to enable assessment of the effectiveness of product training programmes and job aids. PMID:15676470

  15. Hierarchical design of an electro-hydraulic actuator based on robust LPV methods

    NASA Astrophysics Data System (ADS)

    Németh, Balázs; Varga, Balázs; Gáspár, Péter

    2015-08-01

    The paper proposes a hierarchical control design of an electro-hydraulic actuator, which is used to improve the roll stability of vehicles. The purpose of the control system is to generate a reference torque, which is required by the vehicle dynamic control. The control-oriented model of the actuator is formulated in two subsystems. The high-level hydromotor is described in a linear form, while the low-level spool valve is a polynomial system. These subsystems require different control strategies. At the high level, a linear parameter-varying control is used to guarantee performance specifications. At the low level, a control Lyapunov-function-based algorithm, which creates discrete control input values of the valve, is proposed. The interaction between the two subsystems is guaranteed by the spool displacement, which is control input at the high level and must be tracked at the low-level control. The spool displacement has physical constraints, which must also be incorporated into the control design. The robust design of the high-level control incorporates the imprecision of the low-level control as an uncertainty of the system.

  16. Factors that affect the hydraulic performance of raingardens: implications for design and maintenance.

    PubMed

    Virahsawmy, Harry K; Stewardson, Michael J; Vietz, Geoff; Fletcher, Tim D

    2014-01-01

    Raingardens are becoming an increasingly popular technology for urban stormwater treatment. However, their hydraulic performance is known to reduce due to clogging from deposition of fine-grained sediments on the surface. This impacts on their capacity to treat urban runoff. It has been recently hypothesised that plants can help to mitigate the effect of surface clogging on infiltration. A conceptual model is therefore presented to better understand key processes, including those associated with plant cover, which influences surface infiltration mechanisms. Based on this understanding, a field evaluation was carried out to test the hypothesis that plants increase the infiltration rate, and to investigate factors that influence the deposition of fine-grained sediments within raingardens. The results show that infiltration rates around plants are statistically higher than bare areas, irrespective of the degree of surface clogging. This suggests that preferential flow pathways exist around plants. Sediment deposition processes are also influenced by design elements of raingardens such as the inlet configuration. These findings have implications for the design and maintenance of raingardens, in particular the design of the inlet configuration, as well as maintenance of the filter media surface layer and vegetation. PMID:24622546

  17. Feed-pump hydraulic performance and design improvement, Phase I: research program design. Final report

    SciTech Connect

    Brown, W.H.; Gopalakrishnan, S.; Fehlau, R.; Thompson, W.E.; Wilson, D.G.

    1982-03-01

    As a result of prior EPRI-sponsored studies, it was concluded that a research program should be designed and implemented to provide an improved basis for the design, procurement, testing, and operation of large feed pumps with increased reliability and stability over the full range of operating conditions. This two-volume report contains a research plan which is based on a review of the present state of the art and which defines the necessary R and D program and estimates the benefits and costs of the program. The recommended research program consists of 30 interrelated tasks. It is designed to perform the needed research; to verify the results; to develop improved components; and to publish computer-aided design methods, pump specification guidelines, and a troubleshooting manual. Most of the technology proposed in the research plan is applicable to nuclear power plants as well as to fossil-fired plants. This volume discusses the design, performance and failures of feed pumps, and recommendations for research on pump dynamics, design, and specifications.

  18. Two-dimensional Hydraulic Flood Modelling Using Floodplain Topographic and Vegetation Features Derived From Airborne Scanning Laser Al Timetry

    NASA Astrophysics Data System (ADS)

    Mason, D. C.; Cobby, D. M.; Horritt, M. S.; Bates, P. D.

    Two dimensional hydraulic models are currently at the forefront of research into river flood inundation prediction. Airborne scanning laser altimetry (LiDAR) is an important new data source that can provide such models with spatially distributed floodplain topography together with vegetation heights for parameterisation of model friction. The paper discusses how LiDAR data can be used to decompose the model's finite element mesh to reflect floodplain vegetation features such as hedges and trees having different frictional properties to their surroundings, and significant floodplain topographic features having high curvatures. It also investigates how vegetation height data can be used to realisethe currently unexploited potential of 2- D flood models to specify a friction factor at each node of the finite element model mesh. This is shown to obviate the need for a model calibration exercise in which free parameters specifying friction in the channel and floodplain are adjusted to achieve best fit between modelled and observed flood extents. A LiDAR range image segmentation system has been developed to separate ground hits from surface object hits on vegetation or buildings. Ground hits can be used to construct a digital elevation model (DEM) of the underlying ground surface, while surface object hits taken in conjunction with nearby ground hits allow object heights to be determined. The system converts the input height image into two output raster images of surface topography and vegetation height at each point. The river channel and model flood domain extent are also determined, as an aid to constructing the model's finite element mesh. The system segments the image on the basis of local height texture into connected regions of short (grasses and crops <1.34m high), intermediate (hedges and shrubs) and tall vegetation (trees >5m high). For each mesh node, an instantaneous friction factor is calculated at each model timestep, given the frictional material in the

  19. An ontology design pattern for surface water features

    USGS Publications Warehouse

    Sinha, Gaurav; Mark, David; Kolas, Dave; Varanka, Dalia; Romero, Boleslo E.; Feng, Chen-Chieh; Usery, E. Lynn; Liebermann, Joshua; Sorokine, Alexandre

    2014-01-01

    Surface water is a primary concept of human experience but concepts are captured in cultures and languages in many different ways. Still, many commonalities exist due to the physical basis of many of the properties and categories. An abstract ontology of surface water features based only on those physical properties of landscape features has the best potential for serving as a foundational domain ontology for other more context-dependent ontologies. The Surface Water ontology design pattern was developed both for domain knowledge distillation and to serve as a conceptual building-block for more complex or specialized surface water ontologies. A fundamental distinction is made in this ontology between landscape features that act as containers (e.g., stream channels, basins) and the bodies of water (e.g., rivers, lakes) that occupy those containers. Concave (container) landforms semantics are specified in a Dry module and the semantics of contained bodies of water in a Wet module. The pattern is implemented in OWL, but Description Logic axioms and a detailed explanation is provided in this paper. The OWL ontology will be an important contribution to Semantic Web vocabulary for annotating surface water feature datasets. Also provided is a discussion of why there is a need to complement the pattern with other ontologies, especially the previously developed Surface Network pattern. Finally, the practical value of the pattern in semantic querying of surface water datasets is illustrated through an annotated geospatial dataset and sample queries using the classes of the Surface Water pattern.

  20. The design of hydraulic pressure regulators that are stable without the use of sensing line restrictors or frictional dampers

    NASA Technical Reports Server (NTRS)

    Gold, H.

    1977-01-01

    A direct-acting hydraulic pressure regulator design which incorporates stability margin, response and droop margin is developed. The pressure regulator system does not involve a nonlinear sensing line restrictor (which may degrade transient response) or linear damping (which is sensitive to clearance and viscosity). The direct-acting hydraulic pressure regulator makes use of the technique of lead network stabilization (i.e., the tuned stabilizer concept). An analytically derived circuit pressure regulator is tested to study the stability limit under a parallel capacitive plus resistive load and the stabilizing effect of the tuned stabilizer.

  1. Capture-zone design in an aquifer influenced by cyclic fluctuations in hydraulic gradients

    NASA Astrophysics Data System (ADS)

    Zawadzki, Willy; Chorley, Don; Patrick, Guy

    2002-10-01

    Design of a groundwater pumping and treatment system for a wood-treatment facility adjacent to the tidally influenced Fraser River estuary required the development of methodologies to account for cyclic variations in hydraulic gradients. Design of such systems must consider the effects of these cyclic fluctuations on the capture of dissolved-phase contaminants. When the period of the cyclic fluctuation is much less than the travel time of the dissolved contaminant from the source to the discharge point, the hydraulic-gradient variations resulting from these cycles can be ignored. Capture zones are then designed based on the average hydraulic gradient determined using filter techniques on continuous groundwater-level measurements. When the period of cyclic fluctuation in hydraulic gradient is near to or greater than the contaminant travel time, the resulting hydraulic-gradient variations cannot be ignored. In these instances, procedures are developed to account for these fluctuations in the capture-zone design. These include proper characterization of the groundwater regime, assessment of the average travel time and period of the cyclic fluctuations, and numerical techniques which allow accounting for the cyclic fluctuations in the design of the capture zone. Résumé. L'étude d'un système de pompage et de traitement de l'eau souterraine d'une usine de traitement du bois proche de l'estuaire de la rivière Fraser, influencé par les marées, a nécessité la mise au point de méthodologies pour prendre en compte les variations cycliques de gradients hydrauliques. L'étude de tels systèmes doit considérer les effets de ces variations cycliques sur l'extraction des contaminants en phase dissoute. Lorsque la période des variations cycliques est très inférieure au temps de parcours du contaminant dissous entre la source et le point d'émergence, les variations du gradient hydraulique résultant de ces cycles peuvent être ignorées. Les zones d'extraction sont

  2. Experimental design for estimating unknown hydraulic conductivity in an aquifer using a genetic algorithm and reduced order model

    NASA Astrophysics Data System (ADS)

    Ushijima, Timothy T.; Yeh, William W.-G.

    2015-12-01

    We develop an experimental design algorithm to select locations for a network of observation wells that provide the maximum robust information about unknown hydraulic conductivity in a confined, anisotropic aquifer. Since the information that a design provides is dependent on an aquifer's hydraulic conductivity, a robust design is one that provides the maximum information in the worst-case scenario. The design can be formulated as a max-min optimization problem. The problem is generally non-convex, non-differentiable, and contains integer variables. We use a Genetic Algorithm (GA) to perform the combinatorial search. We employ proper orthogonal decomposition (POD) to reduce the dimension of the groundwater model, thereby reducing the computational burden posed by employing a GA. The GA algorithm exhaustively searches for the robust design across a set of hydraulic conductivities and finds an approximate design (called the High Frequency Observation Well Design) through a Monte Carlo-type search. The results from a small-scale 1-D test case validate the proposed methodology. We then apply the methodology to a realistically-scaled 2-D test case.

  3. Manual for the thermal and hydraulic design of direct contact spray columns for use in extracting heat from geothermal brines

    SciTech Connect

    Jacobs, H.R.

    1985-06-01

    This report outlines the current methods being used in the thermal and hydraulic design of spray column type, direct contact heat exchangers. It provides appropriate referenced equations for both preliminary design and detailed performance. The design methods are primarily empirical and are applicable for us in the design of such units for geothermal application and for application with solar ponds. Methods for design, for both preheater and boiler sections of the primary heat exchangers, for direct contact binary powers plants are included. 23 refs., 8 figs.

  4. Numerical design and optimization of hydraulic resistance and wall shear stress inside pressure-driven microfluidic networks.

    PubMed

    Damiri, Hazem Salim; Bardaweel, Hamzeh Khalid

    2015-11-01

    Microfluidic networks represent the milestone of microfluidic devices. Recent advancements in microfluidic technologies mandate complex designs where both hydraulic resistance and pressure drop across the microfluidic network are minimized, while wall shear stress is precisely mapped throughout the network. In this work, a combination of theoretical and modeling techniques is used to construct a microfluidic network that operates under minimum hydraulic resistance and minimum pressure drop while constraining wall shear stress throughout the network. The results show that in order to minimize the hydraulic resistance and pressure drop throughout the network while maintaining constant wall shear stress throughout the network, geometric and shape conditions related to the compactness and aspect ratio of the parent and daughter branches must be followed. Also, results suggest that while a "local" minimum hydraulic resistance can be achieved for a geometry with an arbitrary aspect ratio, a "global" minimum hydraulic resistance occurs only when the aspect ratio of that geometry is set to unity. Thus, it is concluded that square and equilateral triangular cross-sectional area microfluidic networks have the least resistance compared to all rectangular and isosceles triangular cross-sectional microfluidic networks, respectively. Precise control over wall shear stress through the bifurcations of the microfluidic network is demonstrated in this work. Three multi-generation microfluidic network designs are considered. In these three designs, wall shear stress in the microfluidic network is successfully kept constant, increased in the daughter-branch direction, or decreased in the daughter-branch direction, respectively. For the multi-generation microfluidic network with constant wall shear stress, the design guidelines presented in this work result in identical profiles of wall shear stresses not only within a single generation but also through all the generations of the

  5. Design features of the Orion satellite antenna subsystem

    NASA Astrophysics Data System (ADS)

    Waterfield, T. R.

    The ORION satellites (first launch 1994) will provide flexible, high capacity Ku-band communications between and within North America and Europe. Four-fold frequency re-use allows the provision of thirty-four transponders per spacecraft, with two-way networking traffic to 1.2 meter rooftop Very Small Aperture Terminals (VSAT). This paper provides an overview of the communications antenna subsystem and highlights some of the novel and sophisticated design features. These include the following: numerically shaped, gridded reflectors; computer optimized multi-horn feed geometry; feed coefficients optimized under mutual coupling; reconfigurable beams via on-board switching; very low thermal-distortion reflectors; novel sunshield design; and two-axis boresight trimming. Selected analyses and measurement results available at the time of writing are presented.

  6. Design of haptic master featuring small-sized MR brakes

    NASA Astrophysics Data System (ADS)

    Gang, Han Gyeol; Choi, Seung-Bok; Sohn, Jung Woo

    2016-04-01

    In this work, a new type of haptic master featuring small-sized MR brake is proposed and its performances are evaluated. The proposed haptic master consists of base frame, stick grip and small-sized four MR brakes for 3-DOF rotational motion and 1-DOF gripper motion. To obtain large braking torque under limited small size of MR brake, dual tapered shape inner magnetic core is proposed and its performance is evaluated via both numerical estimation and experimental test. After design and implementation of control algorithm, it has been demonstrated through experiment that the proposed actuator has good performances on tracking control of desired torques. Then, a new haptic master device is designed and constructed by adopting the proposed MR brakes and light weight frame structures. It is verified that the proposed haptic master device is effective for the real application in the field.

  7. Effect of the method of estimation of soil saturated hydraulic conductivity with regards to the design of stormwater infiltration trenches

    NASA Astrophysics Data System (ADS)

    Paiva coutinho, Artur; Predelus, Dieuseul; Lassabatere, Laurent; Ben Slimene, Erij; Celso Dantas Antonino, Antonio; Winiarski, Thierry; Joaquim da Silva Pereira Cabral, Jaime; Angulo-Jaramillo, Rafael

    2014-05-01

    Best management practices are based on the infiltration of stormwater (e.g. infiltration into basins or trenches) to reduce the risk of flooding of urban areas. Proper estimations of saturated hydraulic conductivity of the vadose zone are required to avoid inappropriate design of infiltration devices. This article aims at assessing (i) the method-dependency of the estimation of soils saturated hydraulic conductivity and (ii) the consequences of such dependency on the design of infiltration trenches. This is illustrated for the specific case of an infiltration trench to be constructed to receive stormwater from a specific parking surface, 250 m2 in area, in Recife (Brazil). Water infiltration experiments were conducted according to the Beerkan Method, i.e. application of a zero water pressure head through a disc source (D=15 cm) and measures of the amount of infiltrated water with time. Saturated hydraulic conductivity estimates are derived from the analysis of these infiltration tests using several different conceptual approaches: one-dimensional models of Horton(1933) and Philip(1957), three-dimensional methods recently developed (Lassabatere et al., 2006, Wu et al., 1999, and Bagarello et al., 2013) and direct 3-dimensional numerical inversion. The estimations for saturated hydraulic conductivity ranged between 65.5 mm/h and 94 mm/h for one-dimensional methods, whereas using three-dimensional methods saturated hydraulic conductivity ranged between 15.6 mm/h and 50 mm/h. These results shows the need for accounting for 3D geometry, and more generally, the physics of water infiltration in soils, if a proper characterization of soil saturated hydraulic conductivity is targeted. In a second step, each estimate of the saturated hydraulic conductivity was used to calculate the stormwater to be stored in the studied trench for several rainfall events of recurrence intervals of 2 to 25 years. The calculation of these volumes showed a great sensitivity with regards to the

  8. Thermal hydraulic design analysis of ternary carbide fueled square-lattice honeycomb nuclear rocket engine

    SciTech Connect

    Furman, Eric M.; Anghaie, Samim

    1999-01-22

    A computational analysis is conducted to determine the optimum thermal-hydraulic design parameters for a square-lattice honeycomb nuclear rocket engine core that will incorporate ternary carbide based uranium fuels. Recent studies at the Innovative Nuclear Space Power and Propulsion Institute (INSPI) have demonstrated the feasibility of processing solid solution, ternary carbide fuels such as (U, Zr, Nb)C, (U, Zr, Ta)C, (U, Zr, Hf)C and (U, Zr, W)C. The square-lattice honeycomb design provides high strength and is amenable to the processing complexities of these ultrahigh temperature fuels. A parametric analysis is conducted to examine how core geometry, fuel thickness and the propellant flow area effect the thermal performance of the nuclear rocket engine. The principal variables include core size (length and diameter) and fuel element dimensions. The optimum core configuration requires a balance between high specific impulse and thrust level performance, and maintaining the temperature and strength limits of the fuel. A nuclear rocket engine simulation code is developed and used to examine the system performance as well as the performance of the main reactor core components. The system simulation code was originally developed for analysis of NERVA-Derivative and Pratt and Whitney XNR-2000 nuclear thermal rockets. The code is modified and adopted to the square-lattice geometry of the new fuel design. Thrust levels ranging from 44,500 to 222,400 N (10,000 to 50,000 lbf) are considered. The average hydrogen exit temperature is kept at 2800 K, which is well below the melting point of these fuels. For a nozzle area ratio of 300 and a thrust chamber pressure of 4.8 Mpa (700 psi), the specific impulse is 930 s. Hydrogen temperature and pressure distributions in the core and the fuel maximum temperatures are calculated.

  9. An Ontology Design Pattern for Surface Water Features

    SciTech Connect

    Sinha, Gaurav; Mark, David; Kolas, Dave; Varanka, Dalia; Romero, Boleslo E; Feng, Chen-Chieh; Usery, Lynn; Liebermann, Joshua; Sorokine, Alexandre

    2014-01-01

    Surface water is a primary concept of human experience but concepts are captured in cultures and languages in many different ways. Still, many commonalities can be found due to the physical basis of many of the properties and categories. An abstract ontology of surface water features based only on those physical properties of landscape features has the best potential for serving as a foundational domain ontology. It can then be used to systematically incor-porate concepts that are specific to a culture, language, or scientific domain. The Surface Water ontology design pattern was developed both for domain knowledge distillation and to serve as a conceptual building-block for more complex surface water ontologies. A fundamental distinction is made in this on-tology between landscape features that act as containers (e.g., stream channels, basins) and the bodies of water (e.g., rivers, lakes) that occupy those containers. Concave (container) landforms semantics are specified in a Dry module and the semantics of contained bodies of water in a Wet module. The pattern is imple-mented in OWL, but Description Logic axioms and a detailed explanation is provided. The OWL ontology will be an important contribution to Semantic Web vocabulary for annotating surface water feature datasets. A discussion about why there is a need to complement the pattern with other ontologies, es-pecially the previously developed Surface Network pattern is also provided. Fi-nally, the practical value of the pattern in semantic querying of surface water datasets is illustrated through a few queries and annotated geospatial datasets.

  10. Design of a hydraulic analog of the circulatory system for evaluating artificial hearts.

    PubMed

    Donovan, F M

    1975-01-01

    A major problem in improving artificial heart designs is the absence of methods for accurate in vitro testing of artificial heart systems. A mock circulatory system has been constructed which hydraulically simulates the systemic and pulmonary circulations of the normal human. The device is constructed of 1/2 in. acrylic sheet and has overall dimensions of 24 in. wide, 16 in. tall, and 8 in. deep. The artificial heart to be tested is attached to the front of the device, and pumps fluid from the systemic venous chamber into the pulmonary arterial chamber and from the pulmonary venous chamber into the systemic arterial chamber. Each of the four chambers is hermetically sealed. The compliance of each chamber is determined by the volume of air trapped above the fluid in that chamber. The pulmonary and systemic resistances are set automatically by bellows-operated valves to simulate the barroreceptor response in the systemic arteries and the passive pulmonary resistance response in the pulmonary arteries. Cardiac output is measured by a turbine flowmeter in the systemic circulation. Results using the Kwan-Gett artificial heart show a good comparison between the mock circulatory system response and the calf response. PMID:1225373

  11. Thermal-Hydraulic Design of a Fluoride High-Temperature Demonstration Reactor

    SciTech Connect

    Carbajo, Juan J; Qualls, A L

    2016-01-01

    INTRODUCTION The Fluoride High-Temperature Reactor (FHR) named the Demonstration Reactor (DR) is a novel reactor concept using molten salt coolant and TRIstructural ISOtropic (TRISO) fuel that is being developed at Oak Ridge National Laboratory (ORNL). The objective of the FHR DR is to advance the technology readiness level of FHRs. The FHR DR will demonstrate technologies needed to close remaining gaps to commercial viability. The FHR DR has a thermal power of 100 MWt, very similar to the SmAHTR, another FHR ORNL concept (Refs. 1 and 2) with a power of 125 MWt. The FHR DR is also a small version of the Advanced High Temperature Reactor (AHTR), with a power of 3400 MWt, cooled by a molten salt and also being developed at ORNL (Ref. 3). The FHR DR combines three existing technologies: (1) high-temperature, low-pressure molten salt coolant, (2) high-temperature coated-particle TRISO fuel, (3) and passive decay heat cooling systems by using Direct Reactor Auxiliary Cooling Systems (DRACS). This paper presents FHR DR thermal-hydraulic design calculations.

  12. Thermal Hydraulic Design and Analysis of a Water-Cooled Ceramic Breeder Blanket with Superheated Steam for CFETR

    NASA Astrophysics Data System (ADS)

    Cheng, Xiaoman; Ma, Xuebin; Jiang, Kecheng; Chen, Lei; Huang, Kai; Liu, Songlin

    2015-09-01

    The water-cooled ceramic breeder blanket (WCCB) is one of the blanket candidates for China fusion engineering test reactor (CFETR). In order to improve power generation efficiency and tritium breeding ratio, WCCB with superheated steam is under development. The thermal-hydraulic design is the key to achieve the purpose of safe heat removal and efficient power generation under normal and partial loading operation conditions. In this paper, the coolant flow scheme was designed and one self-developed analytical program was developed, based on a theoretical heat transfer model and empirical correlations. Employing this program, the design and analysis of related thermal-hydraulic parameters were performed under different fusion power conditions. The results indicated that the superheated steam water-cooled blanket is feasible. supported by the National Special Project for Magnetic Confined Nuclear Fusion Energy of China (Nos. 2013GB108004, 2014GB122000 and 2014GB119000), and National Natural Science Foundation of China (No. 11175207)

  13. Evaluation of multiple hydraulic models in generating design/near-real time flood inundation extents under various geophysical settings

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Rajib, M. A.; Jafarzadegan, K.; Merwade, V.

    2015-12-01

    Application of land surface/hydrologic models within an operational flood forecasting system can provide probable time of occurrence and magnitude of streamflow at specific locations along a stream. Creating time-varying spatial extent of flood inundation and depth requires the use of a hydraulic or hydrodynamic model. Models differ in representing river geometry and surface roughness which can lead to different output depending on the particular model being used. The result from a single hydraulic model provides just one possible realization of the flood extent without capturing the uncertainty associated with the input or the model parameters. The objective of this study is to compare multiple hydraulic models toward generating ensemble flood inundation extents. Specifically, relative performances of four hydraulic models, including AutoRoute, HEC-RAS, HEC-RAS 2D, and LISFLOOD are evaluated under different geophysical conditions in several locations across the United States. By using streamflow output from the same hydrologic model (SWAT in this case), hydraulic simulations are conducted for three configurations: (i) hindcasting mode by using past observed weather data at daily time scale in which models are being calibrated against USGS streamflow observations, (ii) validation mode using near real-time weather data at sub-daily time scale, and (iii) design mode with extreme streamflow data having specific return periods. Model generated inundation maps for observed flood events both from hindcasting and validation modes are compared with remotely sensed images, whereas the design mode outcomes are compared with corresponding FEMA generated flood hazard maps. The comparisons presented here will give insights on probable model-specific nature of biases and their relative advantages/disadvantages as components of an operational flood forecasting system.

  14. Salient electrical design features of the Magat hydroelectric project

    SciTech Connect

    Verma, R.; Samorio, R.

    1987-06-01

    The Magat River Multipurpose project on the Luzon grid of the National Power Corporation of the Philippines consists of a four unit 450 MVA powerplant placed in service towards end of year 1983 and early 1984, providing an additional installed capacity of 360 MW to the existing generation peak capacity of 2478 MW (1) of the Luzon grid, which is the country's largest grid with an installed capacity of 3906 MW, the other two being those of Visayas and Mindanao with a total installed capacity of 1095 MW. This paper describes the salient features of the electrical design including the main generation and station service single line schemes, the principal equipment parameters and layout, control and protection schemes and grounding system of the power plant.

  15. Launch vehicle payload adapter design with vibration isolation features

    NASA Astrophysics Data System (ADS)

    Thomas, Gareth R.; Fadick, Cynthia M.; Fram, Bryan J.

    2005-05-01

    Payloads, such as satellites or spacecraft, which are mounted on launch vehicles, are subject to severe vibrations during flight. These vibrations are induced by multiple sources that occur between liftoff and the instant of final separation from the launch vehicle. A direct result of the severe vibrations is that fatigue damage and failure can be incurred by sensitive payload components. For this reason a payload adapter has been designed with special emphasis on its vibration isolation characteristics. The design consists of an annular plate that has top and bottom face sheets separated by radial ribs and close-out rings. These components are manufactured from graphite epoxy composites to ensure a high stiffness to weight ratio. The design is tuned to keep the frequency of the axial mode of vibration of the payload on the flexibility of the adapter to a low value. This is the main strategy adopted for isolating the payload from damaging vibrations in the intermediate to higher frequency range (45Hz-200Hz). A design challenge for this type of adapter is to keep the pitch frequency of the payload above a critical value in order to avoid dynamic interactions with the launch vehicle control system. This high frequency requirement conflicts with the low axial mode frequency requirement and this problem is overcome by innovative tuning of the directional stiffnesses of the composite parts. A second design strategy that is utilized to achieve good isolation characteristics is the use of constrained layer damping. This feature is particularly effective at keeping the responses to a minimum for one of the most important dynamic loading mechanisms. This mechanism consists of the almost-tonal vibratory load associated with the resonant burn condition present in any stage powered by a solid rocket motor. The frequency of such a load typically falls in the 45-75Hz range and this phenomenon drives the low frequency design of the adapter. Detailed finite element analysis is

  16. Ecological Engineering Approaches to Improve Hydraulic Properties of Infiltration Basins Designed for Groundwater Recharge.

    PubMed

    Gette-Bouvarot, Morgane; Volatier, Laurence; Lassabatere, Laurent; Lemoine, Damien; Simon, Laurent; Delolme, Cécile; Mermillod-Blondin, Florian

    2015-08-18

    Infiltration systems are increasingly used in urban areas for groundwater recharge. The reduction of sediment permeability by physical and/or biological processes is a major problem in management of infiltration systems often requiring expensive engineering operations for hydraulic performance maintenance. To reduce these costs and for the sake of sustainable development, we proposed to evaluate the ability of ecological engineering approaches to reduce the biological clogging of infiltration basins. A 36-day field-scale experiment using enclosures was performed to test the influences of abiotic (light reduction by shading) and biotic (introduction of the macrophyte Vallisneria spiralis (L.) or the gastropod Viviparus viviparus (Linnaeus, 1758)) treatments to limit benthic biofilm biomass and to maintain or even increase hydraulic performances. We coupled biological characterization of sediment (algal biomass, bacterial abundance, total organic carbon, total nitrogen, microbial enzymatic activity, photosynthetic activity, and photosystem II efficiency) with hydraulic conductivity measurements to assess the effects of treatments on sediment permeability. The grazer Viviparus viviparus significantly reduced benthic biofilm biomass and enhanced hydraulic conductivity. The other treatments did not produce significant changes in hydraulic conductivity although Vallisneria spiralis affected photosynthetic activity of biofilm. Finally, our results obtained with Viviparus viviparus are promising for the development of ecological engineering solutions to prevent biological fouling in infiltration systems. PMID:26214709

  17. Designing Crane Controls with applied Mechanical and Electrical Safety Features

    NASA Technical Reports Server (NTRS)

    Lytle, Bradford P.; Walczak, Thomas A.; Delgado, H. (Technical Monitor)

    2002-01-01

    The use of overhead traveling bridge cranes in many varied applications is common practice. In particular, the use of cranes in the nuclear, military, commercial, aerospace, and other industries can involve safety critical situations. Considerations for Human Injury or Casualty, Loss of Assets, Endangering the Environment, or Economic Reduction must be addressed. Traditionally, in order to achieve additional safety in these applications, mechanical systems have been augmented with a variety of devices. These devices assure that a mechanical component failure shall reduce the risk of a catastrophic loss of the correct and/or safe load carrying capability. ASME NOG-1-1998, (Rules for Construction of Overhead and Gantry Cranes, Top Running Bridge, and Multiple Girder), provides design standards for cranes in safety critical areas. Over and above the minimum safety requirements of todays design standards, users struggle with obtaining a higher degree of reliability through more precise functional specifications while attempting to provide "smart" safety systems. Electrical control systems also may be equipped with protective devices similar to the mechanical design features. Demands for improvement of the cranes "control system" is often recognized, but difficult to quantify for this traditionally "mechanically" oriented market. Finite details for each operation must be examined and understood. As an example, load drift (or small motions) at close tolerances can be unacceptable (and considered critical). To meet these high functional demands encoders and other devices are independently added to control systems to provide motion and velocity feedback to the control drive. This paper will examine the implementation of Programmable Electronic Systems (PES). PES is a term this paper will use to describe any control system utilizing any programmable electronic device such as Programmable Logic Controllers (PLC), or an Adjustable Frequency Drive (AID) 'smart' programmable

  18. SCW Pressure-Channel Nuclear Reactor Some Design Features

    NASA Astrophysics Data System (ADS)

    Pioro, Igor L.; Khan, Mosin; Hopps, Victory; Jacobs, Chris; Patkunam, Ruban; Gopaul, Sandeep; Bakan, Kurtulus

    Concepts of nuclear reactors cooled with water at supercritical pressures were studied as early as the 1950s and 1960s in the USA and Russia. After a 30-year break, the idea of developing nuclear reactors cooled with SuperCritical Water (SCW) became attractive again as the ultimate development path for water cooling. The main objectives of using SCW in nuclear reactors are: 1) to increase the thermal efficiency of modern Nuclear Power Plants (NPPs) from 30-35% to about 45-48%, and 2) to decrease capital and operational costs and hence decrease electrical energy costs (˜1000 US/kW or even less). SCW NPPs will have much higher operating parameters compared to modern NPPs (pressure about 25 MPa and outlet temperature up to 625°C), and a simplified flow circuit, in which steam generators, steam dryers, steam separators, etc., can be eliminated. Also, higher SCW temperatures allow direct thermo-chemical production of hydrogen at low cost, due to increased reaction rates. Pressure-tube or pressure-channel SCW nuclear reactor concepts are being developed in Canada and Russia for some time. Some design features of the Canadian concept related to fuel channels are discussed in this paper. The main conclusion is that the development of SCW pressure-tube nuclear reactors is feasible and significant benefits can be expected over other thermal-energy systems.

  19. The design of hydraulic pressure regulators that are stable without the use of sensing line restrictors or frictional dampers

    NASA Technical Reports Server (NTRS)

    Gold, H.

    1977-01-01

    Parameters controlled in design determine the stability of hydraulic pressure regulators in service. The non-linear sensing line restrictor can provide stability, but degrades the transient response. Linear damping is not always physically realizable and is sensitive to clearance and viscosity. Design relationships are analytically derived through which regulators can be made to be stable without the use of either of these damping means. The analytical distinctions between the parameters derived and those in prior literature are discussed. An analytically derived circuit component that stabilizes an otherwise unstable regulator and its experimental verification is described.

  20. The Design Features of the National Writing Project's New Teacher Initiative

    ERIC Educational Resources Information Center

    Heenan, Barbara; Houghton, Nina

    2006-01-01

    This report describes the key design features of the new teacher support programs that emerged from the National Writing Project (NWP) New Teacher Initiative (NTI). As the New Teacher Initiative unfolded, a number of design features appeared frequently and consistently across the sites. This report explains how these design features of the NTI are…

  1. Analysis of the OECD Main Steam Line Break Benchmark Problem Using the Refined Core Thermal-Hydraulic Nodalization Feature of the MARS/MASTER Code

    SciTech Connect

    Joo, Han Gyu; Jeong, Jae-Jun; Cho, Byung-Oh; Lee, Won Jae; Zee, Sung Quun

    2003-05-15

    The refined core thermal-hydraulics (T-H) nodalization feature of the MARS/MASTER code is used to generate a high-fidelity solution to the OECD main steam line break benchmark problem and to investigate the effects of core T-H nodalization. The MARS/MASTER coupling scheme is introduced first that enables efficient refined node core T-H calculations via the COBRA-III module. The base solution is generated using a fine T-H nodalization consisting of fuel assembly-sized radial nodes. Sensitivity studies are performed on core T-H nodalization to examine the impacts on core reactivity, power distribution, and transient behavior. The results indicate that the error in the peak local power can be very large (up to 25%) with a coarse T-H nodalization because of the inability to incorporate detailed thermal feedback. A demonstrative departure from nucleate boiling (DNB) calculation shows no occurrence of DNB in this problem.

  2. New and Improved Integrated Optical Design Analysis (IODA) Software Features

    NASA Technical Reports Server (NTRS)

    Troy, Edward; Moore, James D., Jr.; Montgomery, Edward E. (Technical Monitor)

    2002-01-01

    New features have been added to IODA to support testing of lightweight optics. Algorithms have been developed to predict actuator influence functions and positions to correct for gravity loading effects. New features have also been added to import measured test data and to compare measured data with predicted data.

  3. Design and operation of mechanical and hydraulic bit releases. Technical report

    SciTech Connect

    Peterson, M.N.A.

    1984-02-01

    The Deep Sea Drilling Project Technical Report documents the history, incentives and development details of the bit release technology used aboard the GLOMAR CHALLENGER. Descriptions of the most current models and operational guidelines for both the earlier Mechanical Bit Release (MBR) and the later Hydraulic Bit Release (HBR) are included. Operational deployments of both systems are summarized. Appendices are included with certain significant engineering calculations and machine drawings.

  4. Drop Accidents in the Canister Storage Building (CSB) Addressed by Design Features and or Design Calculations

    SciTech Connect

    SEXTON, R.A.

    2000-01-06

    A variety of drop shear or impact scenarios have been identified for the Canister Storage Building. Some of these are being addressed by new calculations or require no specific action. This document describes five of them which are addressed by design features and/or existing design calculations. For each of the five a position is stated indicating the reason for assurance that the safety functions of the MCO will not be jeopardized by the accident. Following the position is a description of the basis for that position.

  5. Do Particular Design Features Assist People with Aphasia to Comprehend Text? An Exploratory Study

    ERIC Educational Resources Information Center

    Wilson, Lucy; Read, Jennifer

    2016-01-01

    Background: Much of the evidence underlying guidelines for producing accessible information for people with aphasia focuses on client preference for particular design features. There is limited evidence regarding the effects of these features on comprehension. Aims: To examine the effects of specific design features on text comprehension. It was…

  6. Designing for adaptation to novelty and change: functional information, emergent feature graphics, and higher-level control.

    PubMed

    Hajdukiewicz, John R; Vicente, Kim J

    2002-01-01

    Ecological interface design (EID) is a theoretical framework that aims to support worker adaptation to change and novelty in complex systems. Previous evaluations of EID have emphasized representativeness to enhance generalizability of results to operational settings. The research presented here is complementary, emphasizing experimental control to enhance theory building. Two experiments were conducted to test the impact of functional information and emergent feature graphics on adaptation to novelty and change in a thermal-hydraulic process control microworld. Presenting functional information in an interface using emergent features encouraged experienced participants to become perceptually coupled to the interface and thereby to exhibit higher-level control and more successful adaptation to unanticipated events. The absence of functional information or of emergent features generally led to lower-level control and less success at adaptation, the exception being a minority of participants who compensated by relying on analytical reasoning. These findings may have practical implications for shaping coordination in complex systems and fundamental implications for the development of a general unified theory of coordination for the technical, human, and social sciences. Actual or potential applications of this research include the design of human-computer interfaces that improve safety in complex sociotechnical systems. PMID:12691368

  7. Binding the Electronic Book: Design Features for Bibliophiles

    ERIC Educational Resources Information Center

    Ruecker, Stan; Uszkalo, Kirsten C.

    2007-01-01

    This paper proposes a design for the electronic book based on discussions with frequent book readers. We adopted a conceptual framework for this project consisting of a spectrum of possible designs, with the conventional bound book at one difference pole, and the laptop computer at the other; the design activity then consisted of appropriately…

  8. Fluid Power/Basic Hydraulics. Instructor's Guide.

    ERIC Educational Resources Information Center

    Stanbery, Richard

    This guide is designed to assist industrial vocational instructors in teaching a course on fluid power and basic hydraulics. Covered in the unit on the basics of fluid power and hydraulics are the following topics: the fundamentals of fluid power and hydraulics, basic hydraulic circuits, and servicing a hydraulic jack. The second unit, consisting…

  9. Thermal hydraulic method for whole core design analysis of an HTGR

    SciTech Connect

    Huning, A. J.; Garimella, S.

    2013-07-01

    A new thermal hydraulic method and initial results are presented for core-wide steady state analysis of prismatic High Temperature Gas-Cooled Reactors (HTGR). The method allows for the complete solution of temperature and coolant mass flow distribution by solving quasi-steady energy balances for the discretized core. Assembly blocks are discretized into unit cells for which the average temperature of each unit cell is determined. Convective heat removal is coupled to the unit cell energy balances by a 1-D axial flow model. The flow model uses established correlations for friction factor and Nusselt number. Bypass flow is explicitly calculated by using an initial guess for mass flow distribution and determining the exit pressure of each flow channel. The mass flow distribution is updated until a uniform core exit pressure condition is reached. Results are obtained for the MHTGR-350 with emphasis on the change in thermal hydraulic parameters due to various steady state power profiles and bypass gap widths. Steady state temperature distribution and its variations are discussed. (authors)

  10. The influence of the design features on optical sorter effectiveness

    NASA Astrophysics Data System (ADS)

    Pavlenko, Nikita A.; Korotaev, Valery V.

    2015-05-01

    Paper deals with investigation of factors which may have a significant negative impact on the process of mineral raw material enrichment by optical sorting method. The studies were conducted using experimental setup which is a prototype of an optical sorter for sorting mineral objects of small size. Special software was developed in the LabVIEW for experimental setup control and analysis of experimental results. The impact of illumination features, as well as used lens were analyzed.

  11. Design and Construction of Experiment for Direct Electron Irradiation of Uranyl Sulfate Solution: Bubble Formation and Thermal Hydraulics Studies

    SciTech Connect

    Chemerisov, Sergey; Gromov, Roman; Makarashvili, Vakho; Heltemes, Thad; Sun, Zaijing; Wardle, Kent E.; Bailey, James; Quigley, Kevin; Stepinski, Dominique; Vandegrift, George

    2014-10-01

    Argonne is assisting SHINE Medical Technologies in developing SHINE, a system for producing fission-product 99Mo using a D/T-accelerator to produce fission in a non-critical target solution of aqueous uranyl sulfate. We have developed an experimental setup for studying thermal-hydraulics and bubble formation in the uranyl sulfate solution to simulate conditions expected in the SHINE target solution during irradiation. A direct electron beam from the linac accelerator will be used to irradiate a 20 L solution (sector of the solution vessel). Because the solution will undergo radiolytic decomposition, we will be able to study bubble formation and dynamics and effects of convection and temperature on bubble behavior. These experiments will serve as a verification/ validation tool for the thermal-hydraulic model. Utilization of the direct electron beam for irradiation allows homogeneous heating of a large solution volume and simplifies observation of the bubble dynamics simultaneously with thermal-hydraulic data collection, which will complement data collected during operation of the miniSHINE experiment. Irradiation will be conducted using a 30-40 MeV electron beam from the high-power linac accelerator. The total electron-beam power will be 20 kW, which will yield a power density on the order of 1 kW/L. The solution volume will be cooled on the front and back surfaces and central tube to mimic the geometry of the proposed SHINE solution vessel. Also, multiple thermocouples will be inserted into the solution vessel to map thermal profiles. The experimental design is now complete, and installation and testing are in progress.

  12. Parameter-dependent vibration-attenuation controller design for electro-hydraulic actuated linear structural systems

    NASA Astrophysics Data System (ADS)

    Weng, Falu; Mao, Weijie

    2012-03-01

    The problem of robust active vibration control for a class of electro-hydraulic actuated structural systems with time-delay in the control input channel and parameter uncertainties appearing in all the mass, damping and stiffness matrices is investigated in this paper. First, by introducing a linear varying parameter, the nonlinear system is described as a linear parameter varying (LPV) model. Second, based on this LPV model, an LMI-based condition for the system to be asymptotically stabilized is deduced. By solving these LMIs, a parameter-dependent controller is established for the closedloop system to be stable with a prescribed level of disturbance attenuation. The condition is also extended to the uncertain case. Finally, some numerical simulations demonstrate the satisfying performance of the proposed controller.

  13. Hydraulic Resistance of Vitreous Cutters: The Impact of Blade Design and Cut Rate

    PubMed Central

    Rossi, Tommaso; Querzoli, Giorgio; Angelini, Giampiero; Malvasi, Carlo; Rossi, Alessandro; Morini, Mario; Esposito, Graziana; Micera, Alessandra; di Luca, Natale Mario; Ripandelli, Guido

    2016-01-01

    Purpose To measure the hydraulic resistance (HR) of vitreous cutters equipped with a Regular guillotine Blade (RB) or double edge blade (DEB) at cut rates comprised between 0 and 12,000 cuts per minute (CPM) and compare it with vitreous fragment size. This was an in vitro experimental study; in vivo HR measure and vitreous sampling. Methods HR, defined as aspiration pressure/flow rate, was measured in balanced salt solution (BSS; Alcon, Fort Worth, TX) (in vitro) and during pars plana vitrectomy of 20 consecutive patients aged 18 to 65, undergoing macular surgery. HR was recorded at increasing cut rates (500–6000 CPM for the RB and 500–12,000 CPM for the DEB; 5 mL/min flow). Vitreous samples were withdrawn and analyzed with Western and collagen type II and IX immunostaining to evaluate protein size. The main outcome measures were hydraulic resistance (mm Hg/ml/min [±SD]) and optic density for Western blot and immunostaining. Results RB and DEB showed identical HR in BSS between 0 and 3000 CPM. Above 3000 CPM, RB HR steadily increased, and was significantly higher than DEB HR. Vitreous HR was also similar for the two blades between 0 and 1500 CPM. Above 1500 CPM, RB offered a significantly higher resistance. Western blot and immunostaining of vitreous samples did not yield a significant difference in size, regardless of blade type and cut rate. Conclusions DEB is more efficient, offering a lower HR than RB over 1500 CPM in human vitreous. There is no viscosity reduction as a function of cut-rate between 1500 and 12,000 CPM, as HR does not vary. Translational Relevance Future vitreous cutters will benefit of a DEB; optimal cut rate needs to be defined, and the simple increase of cut rate does not provide benefits after a certain limit to be assessed. PMID:27441099

  14. Experimental Design for Estimating Unknown Hydraulic Conductivity in a Confined Aquifer using a Genetic Algorithm and a Reduced Order Model

    NASA Astrophysics Data System (ADS)

    Ushijima, T.; Yeh, W.

    2013-12-01

    An optimal experimental design algorithm is developed to select locations for a network of observation wells that provides the maximum information about unknown hydraulic conductivity in a confined, anisotropic aquifer. The design employs a maximal information criterion that chooses, among competing designs, the design that maximizes the sum of squared sensitivities while conforming to specified design constraints. Because that the formulated problem is non-convex and contains integer variables (necessitating a combinatorial search), for a realistically-scaled model, the problem may be difficult, if not impossible, to solve through traditional mathematical programming techniques. Genetic Algorithms (GAs) are designed to search out the global optimum; however because a GA requires a large number of calls to a groundwater model, the formulated optimization problem may still be infeasible to solve. To overcome this, Proper Orthogonal Decomposition (POD) is applied to the groundwater model to reduce its dimension. The information matrix in the full model space can then be searched without solving the full model.

  15. A new multi-electrode array design for chronic neural recording, with independent and automatic hydraulic positioning.

    PubMed

    Sato, T; Suzuki, T; Mabuchi, K

    2007-02-15

    We report on a new microdrive design, which enables the construction of multi-electrode arrays capable of chronically recording the multi-unit neural activity of waking animals. Our principal motivation for inventing this device was to simplify the task of positioning electrodes, which consumes a considerable amount of time and requires a high level of skill. With the new microdrives, each electrode is independently and automatically driven into place. A hydraulic drive system is adopted to reduce the size, weight, and cost of the structure. The hydraulic fluid is also used as a part of the electrical circuit, and facilitates the wiring of the electrodes. A routing system has been attached to reduce the number of tube connections. The microdrive is cylindrical, has a diameter of 23.5 mm, a height of 37 mm, and a weight of 15 g. It allows for up to 22 electrodes, which are arranged on a 0.35 mm grid. Each electrode can be positioned at any depth up to approximately 4mm. The microdrive was evaluated under acute and chronic recording experiments, and is shown to be capable of automatically positioning each electrode and successfully recording the neural signals of waking rats. PMID:16996616

  16. Design features and results from fatigue reliability research machines.

    NASA Technical Reports Server (NTRS)

    Lalli, V. R.; Kececioglu, D.; Mcconnell, J. B.

    1971-01-01

    The design, fabrication, development, operation, calibration and results from reversed bending combined with steady torque fatigue research machines are presented. Fifteen-centimeter long, notched, SAE 4340 steel specimens are subjected to various combinations of these stresses and cycled to failure. Failure occurs when the crack in the notch passes through the specimen automatically shutting down the test machine. These cycles-to-failure data are statistically analyzed to develop a probabilistic S-N diagram. These diagrams have many uses; a rotating component design example given in the literature shows that minimum size and weight for a specified number of cycles and reliability can be calculated using these diagrams.

  17. Aircraft-crash-locating transmitter features design improvements

    NASA Technical Reports Server (NTRS)

    Manoli, R.; Ulrich, B. R.

    1971-01-01

    Crash locater is automatically ejected from aircraft at time of crash and begins transmitting at emergency radio frequencies monitored by all airports and airport control towers. Advantages are smaller size, simpler design and installation, extended transmitting range and life, greater deployment reliability and increased crash resistance.

  18. ENVIRONMENTAL HYDRAULICS

    EPA Science Inventory

    The thermal, chemical, and biological quality of water in rivers, lakes, reservoirs, and near coastal areas is inseparable from a consideration of hydraulic engineering principles: therefore, the term environmental hydraulics. In this chapter we discuss the basic principles of w...

  19. A Comparison of Student and Instructor Preferences for Design and Pedagogy Features in Online Courses

    ERIC Educational Resources Information Center

    Hu, Xiaolin Charlene

    2009-01-01

    The study investigated the preferences of instructors and students for design and pedagogy features of online instruction at the post-secondary level. Features were identified through a comprehensive literature review combined with focus groups. Each feature was subjected to review by subject matter experts to validate the differentiation between…

  20. An integrated database with system optimization and design features

    NASA Technical Reports Server (NTRS)

    Arabyan, A.; Nikravesh, P. E.; Vincent, T. L.

    1992-01-01

    A customized, mission-specific relational database package was developed to allow researchers working on the Mars oxygen manufacturing plant to enter physical description, engineering, and connectivity data through a uniform, graphical interface and to store the data in formats compatible with other software also developed as part of the project. These latter components include an optimization program to maximize or minimize various criteria as the system evolves into its final design; programs to simulate the behavior of various parts of the plant in Martian conditions; an animation program which, in different modes, provides visual feedback to designers and researchers about the location of and temperature distribution among components as well as heat, mass, and data flow through the plant as it operates in different scenarios; and a control program to investigate the stability and response of the system under different disturbance conditions. All components of the system are interconnected so that changes entered through one component are reflected in the others.

  1. 14 CFR 23.1435 - Hydraulic systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Hydraulic systems. 23.1435 Section 23.1435... § 23.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each hydraulic system and its elements must withstand, without yielding, the structural loads expected...

  2. 14 CFR 23.1435 - Hydraulic systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Hydraulic systems. 23.1435 Section 23.1435... § 23.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each hydraulic system and its elements must withstand, without yielding, the structural loads expected...

  3. 14 CFR 23.1435 - Hydraulic systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Hydraulic systems. 23.1435 Section 23.1435... § 23.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each hydraulic system and its elements must withstand, without yielding, the structural loads expected...

  4. 14 CFR 29.1435 - Hydraulic systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 29.1435 Section 29.1435... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each element of the hydraulic system...

  5. 14 CFR 23.1435 - Hydraulic systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 23.1435 Section 23.1435... § 23.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each hydraulic system and its elements must withstand, without yielding, the structural loads expected...

  6. Interactive Universal Design Kiosks: Explanations About Social Inclusion Features in Architectural Design.

    PubMed

    Guimarães, Marcelo Pinto; Picceli, Angélica Fátima Baldin; Sabino, Paulo Roberto

    2016-01-01

    This paper details a set of self-supporting and illuminated panels that work together but independently in order to emphasize the explanation of building features and activities that are based on Universal Design guidelines. The exhibition is based on two structures that are arranged in semi-circles (A and B). They are integrated to form a carpeted path where the visitor will be gradually exposed to the concepts related to the principles of Universal Design. Following the sequence of three-dimensional objects and swivelling box elements that support the tactile information on the subject, it is expected that visitors become familiar with each of the principles being demonstrated. Operated by a control system consisting of keys with colour signage, textures and high relief, the panel on the control table allows the user to choose information about paired relationships between some of seven principles contained in printed images about the architectural design on the set of panels. The effectiveness of the composition can be verified by the time people remain enough to hear, see and touch the kiosks for all the information, or by successive visits users make to the setting. PMID:27534281

  7. The OECD/NEA/NSC PBMR coupled neutronics/thermal hydraulics transient benchmark: The PBMR-400 core design

    SciTech Connect

    Reitsma, F.; Ivanov, K.; Downar, T.; De Haas, H.; Gougar, H. D.

    2006-07-01

    The Pebble Bed Modular Reactor (PBMR) is a High-Temperature Gas-cooled Reactor (HTGR) concept to be built in South Africa. As part of the verification and validation program the definition and execution of code-to-code benchmark exercises are important. The Nuclear Energy Agency (NEA) of the Organisation for Economic Cooperation and Development (OECD) has accepted, through the Nuclear Science Committee (NSC), the inclusion of the Pebble-Bed Modular Reactor (PBMR) coupled neutronics/thermal hydraulics transient benchmark problem in its program. The OECD benchmark defines steady-state and transients cases, including reactivity insertion transients. It makes use of a common set of cross sections (to eliminate uncertainties between different codes) and includes specific simplifications to the design to limit the need for participants to introduce approximations in their models. In this paper the detailed specification is explained, including the test cases to be calculated and the results required from participants. (authors)

  8. Optimal design of an electro-hydraulic valve for heavy-duty vehicle clutch actuator with certain constraints

    NASA Astrophysics Data System (ADS)

    Meng, Fei; Shi, Peng; Karimi, Hamid Reza; Zhang, Hui

    2016-02-01

    The main objective of this paper is to investigate the sensitivity analysis and optimal design of a proportional solenoid valve (PSV) operated pressure reducing valve (PRV) for heavy-duty automatic transmission clutch actuators. The nonlinear electro-hydraulic valve model is developed based on fluid dynamics. In order to implement the sensitivity analysis and optimization for the PRV, the PSV model is validated by comparing the results with data obtained from a real test-bench. The sensitivity of the PSV pressure response with regard to the structural parameters is investigated by using Sobol's method. Finally, simulations and experimental investigations are performed on the optimized prototype and the results reveal that the dynamical characteristics of the valve have been improved in comparison with the original valve.

  9. Thermal Hydraulics Design and Analysis Methodology for a Solid-Core Nuclear Thermal Rocket Engine Thrust Chamber

    NASA Technical Reports Server (NTRS)

    Wang, Ten-See; Canabal, Francisco; Chen, Yen-Sen; Cheng, Gary; Ito, Yasushi

    2013-01-01

    Nuclear thermal propulsion is a leading candidate for in-space propulsion for human Mars missions. This chapter describes a thermal hydraulics design and analysis methodology developed at the NASA Marshall Space Flight Center, in support of the nuclear thermal propulsion development effort. The objective of this campaign is to bridge the design methods in the Rover/NERVA era, with a modern computational fluid dynamics and heat transfer methodology, to predict thermal, fluid, and hydrogen environments of a hypothetical solid-core, nuclear thermal engine the Small Engine, designed in the 1960s. The computational methodology is based on an unstructured-grid, pressure-based, all speeds, chemically reacting, computational fluid dynamics and heat transfer platform, while formulations of flow and heat transfer through porous and solid media were implemented to describe those of hydrogen flow channels inside the solid24 core. Design analyses of a single flow element and the entire solid-core thrust chamber of the Small Engine were performed and the results are presented herein

  10. Exploring design features for enhancing players' challenge in strategy games.

    PubMed

    Hsu, Shang Hwa; Wen, Ming-Hui; Wu, Muh-Cherng

    2007-06-01

    This paper examines how to make a player feel more challenged in a strategic computer game. It is hypothesized that information availability and resource advantage affect play difficulty, which in turn affects the challenge experienced. The difficulty of play can be defined in terms of the mental workload that players experience and the physical effort that players exert. Forty-five male college and graduate students participated in a 3 x 3 (information availability x resource advantage) between-subjects factorial design experiment. This experiment measured player mental workload, physical effort, and challenge. The results indicate that information availability affects player mental workload, and resource advantage affects levels of player physical effort, respectively. Moreover, the relationship between mental workload and challenge was found to be an inverted U-shaped curve; in other words, too much or too little mental workload may decrease player challenge. The relationship between physical effort and challenge exhibited similar characteristics. PMID:17594263

  11. Hydraulic development of high specific-speed pump-turbines by means of an inverse design method, numerical flow-simulation (CFD) and model testing

    NASA Astrophysics Data System (ADS)

    Kerschberger, P.; Gehrer, A.

    2010-08-01

    In recent years an increased interest in pump-turbines has been recognized in the market. The rapid availability of pumped storage schemes and the benefits to the power system by peak lopping, providing reserve and rapid response for frequency control are becoming of growing advantage. In that context it is requested to develop pump-turbines that reliably stand dynamic operation modes, fast changes of the discharge rate by adjusting the variable diffuser vanes as well as fast changes from pump to turbine operation. Within the present study various flow patterns linked to the operation of a pump-turbine system are discussed. In that context pump and turbine mode are presented separately and different load cases at both operation modes are shown. In order to achieve modern, competitive pump-turbine designs it is further explained which design challenges should be considered during the geometry definition of a pump-turbine impeller. Within the present study a runner-blade profile for a low head pump-turbine has been developed. For the initial hydraulic runner-blade design, an inverse design method has been applied. Within this design procedure, a first blade geometry is generated by imposing the pressure loading-distribution and by means of an inverse 3D potential-flow-solution. The hydraulic behavior of both, pump-mode and turbine-mode is then evaluated by solving the full 3D Navier-Stokes equations in combination with a robust turbulence model. Based on this initial design the blade profile has been further optimized and redesigned considering various hydraulic pump-turbine requirements. Finally, the progress in hydraulic design is demonstrated by model test results which show a significant improvement in hydraulic performance compared to an existing reference design.

  12. Micalastic high-voltage insulation: Design features and experience

    NASA Astrophysics Data System (ADS)

    Wichmann, A.

    1981-12-01

    High-quality mica, carefully selected epoxy resins and a well-matched vacuum/pressure impregnation process determine the characteristics of the MICALASTIC insulation for large turbine-generators. Logical development and process manufacturing quality control have led to an insulation system of high quality and operating reliability. The first winding of a turbine-generator being impregnated and cured under vacuum with solvent-free synthetic resin in 1958 was designed for 10.5 kV rated voltage. Ever since, Siemens AG and Kraftwerk Union AG have used this type of insulation for all direct-cooled windings and also for an increasing number of indirect-cooled windings. At present, 240 turbine-generators with a total of more than 115,000 MVA output have been built. Since 1960, this insulation system has been registered for Siemens AG under the trade name MICALASTIC. The stator windings of the largest, single-shaft generators to date, rated 1560 MVA, 27 kV, has been built with MICALASTIC insulation.

  13. New statistical features for the design of fiber optic statistical mode sensors

    NASA Astrophysics Data System (ADS)

    Efendioglu, Hasan S.; Yildirim, Tulay; Toker, Onur; Fidanboylu, Kemal

    2013-08-01

    Novel statistical features are proposed for the design of fiber optic statistical mode sensors. The statistical features are radial pth order moments, more precisely first and second order moments. These new features are compared with correlation and image difference features which were reported in the literature earlier. The fiber optic statistical mode sensor experiments are conducted for different applied loads and the corresponding images are captured using the CCD camera. Different statistical features such as image differencing, correlation, first moment and second moment are extracted from the captured images. These features are compared with each other in terms of different characteristics such as precision error, non-linearity, and hysteresis. It is shown that the first and second order moment statistical features are better alternatives for the design of statistical mode sensors, when precision and linearity characteristics are more important than the hysteresis characteristic.

  14. Scaling of Thermal-Hydraulic Experiments for a Space Rankine Cycle and Selection of a Preconceptual Scaled Experiment Design

    SciTech Connect

    Sulfredge, CD

    2006-01-27

    To assist with the development of a space-based Rankine cycle power system using liquid potassium as the working fluid, a study has been conducted on possible scaled experiments with simulant fluids. This report will consider several possible working fluids and describe a scaling methodology to achieve thermal-hydraulic similarity between an actual potassium system and scaled representations of the Rankine cycle boiler or condenser. The most practical scaling approach examined is based on the selection of perfluorohexane (FC-72) as the simulant. Using the scaling methodology, a series of possible solutions have been calculated for the FC-72 boiler and condenser. The possible scaled systems will then be compared and preconceptual specifications and drawings given for the most promising design. The preconceptual design concept will also include integrating the scaled boiler and scaled condenser into a single experimental loop. All the preconceptual system specifications appear practical from a fabrication and experimental standpoint, but further work will be needed to arrive at a final experiment design.

  15. Design and operation of an advanced hydraulic piston corer. Technical report

    SciTech Connect

    Peterson, M.N.A.

    1984-07-01

    The Deep Sea Drilling Project Technical Report documents the history, incentives, development and testing of the Advanced Piston Corer (APC) - the third generation in the wireline retrievable, piston coring technology in DSDP. Description and operational guidelines of the latest design iteration, APC Mod. II, are included. Operational sea trials of the Mod. I version are summarized. Appendices are included with related reports, design calculations and machine drawings.

  16. Critical Features of Engineering Design in Technology Education. Research in Engineering and Technology Education

    ERIC Educational Resources Information Center

    Asunda, Paul A.; Hill, Roger B.

    2007-01-01

    The purpose of this study was to find critical features of engineering design that can be incorporated within technology education learning activities, and develop a rubric for assessing these features. Data were collected through semi-structured interviews with three professors actively involved in engineering education. Supporting documents such…

  17. Engineering-geological substantiation of the designs of underground hydraulic structures

    SciTech Connect

    Kolichko, A.V.; Razumov, V.K.

    1987-08-01

    The characteristics of engineering-geological substantiation of tunnel facilities for hydroelectric power plants in the mountainous regions of Central Asia and the Caucasus are determined by the current tectonic, seismic, and geologic processes going on there. This paper proposes methodologies for constructing models that are responsive to the peculiarities of the region and that can be used to optimize the tunnels throughout design and construction.

  18. Design features of the GTD 8000 and GTD 15000 marine gas turbine engines

    NASA Astrophysics Data System (ADS)

    Romanov, Viktor I.

    1992-06-01

    An account is given of the design features and performance of the GTD 8000 and GTD 15000 marine gas turbines, whose simple-cycle thermodynamic efficiencyis of the order of 34-35 percent. A development history is presented for the component design improvements through which such performance levels were achieved. Attention is given to the counterflow combustor, bearings, and high pressure compressor/turbine spool rotor joint assembly features. These powerplants are suitable for hydrofoil and hovercraft applications.

  19. Physics and thermal hydraulics design of a small water cooled reactor fuelled with plutonium in rock-like oxide (ROX) form

    SciTech Connect

    Gaultier, M.; Danguy, G.; Perry, A.; Williams, A.; Brushwood, J.; Thompson, A.; Beeley, P. A.

    2006-07-01

    This paper describes the Physics and Thermal Hydraulics areas of a design study for a small water-cooled reactor. The aim was to design a Pressurised Water Reactor (PWR) of maximum power 80 MWt, using a dispersed layout, capable of maximising primary natural circulation flow. The reactor fuel consists of plutonium contained in granular form within a Rock-like Oxide (ROX) pellet structure. (authors)

  20. Final Report - Advanced Hydraulic and Mass Transfer Models for Distillation Column Optimization and Design

    SciTech Connect

    Eldridge, Robert, B.

    2005-10-13

    The project successfully developed a computational fluid dynamics (CFD) based simulation of the hydrodynamics of flow in a commercial structured packing element. This result fulfilled the prime objective of the research program. The simulation utilized commercial CFD code marketed by Fluent Inc. in combination with a novel graphical interface developed by Oak Ridge National Lab. The end product will allow the design of next generation column internals without the need for extensive experimental validation and will expand the fundamental understanding of the vapor-liquid contacting process.

  1. Hydraulic manipulator research at ORNL

    SciTech Connect

    Kress, R.L.; Jansen, J.F.; Love, L.J.

    1997-03-01

    Recently, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. General tasks such as waste storage tank cleanup and facility dismantlement and decommissioning require manipulator life capacities in the range of hundreds of pounds rather than tens of pounds. To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned once again to hydraulics as a means of actuation. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling, analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology, including mobile robots, teleoperated manipulators, and full-scale construction equipment. In addition, to support the development and deployment of new hydraulic manipulators, ORNL has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The purpose of this article is to describe the past hydraulic manipulator developments and current hydraulic manipulator research capabilities at ORNL. Included are example experimental results from ORNL`s flexible/prismatic test stand.

  2. Hydraulic design to optimize the treatment capacity of Multi-Stage Filtration units

    NASA Astrophysics Data System (ADS)

    Mushila, C. N.; Ochieng, G. M.; Otieno, F. A. O.; Shitote, S. M.; Sitters, C. W.

    2016-04-01

    Multi-Stage Filtration (MSF) can provide a robust treatment alternative for surface water sources of variable water quality in rural communities at low operation and maintenance costs. MSF is a combination of Slow Sand Filters (SSFs) and Pre-treatment systems. The general objective of this research was to optimize the treatment capacity of MSF. A pilot plant study was undertaken to meet this objective. The pilot plant was monitored for a continuous 98 days from commissioning till the end of the project. Three main stages of MSF namely: The Dynamic Gravel Filter (DGF), Horizontal-flow Roughing Filter (HRF) and SSF were identified, designed and built. The response of the respective MSF units in removal of selected parameters guiding drinking water quality such as microbiological (Faecal and Total coliform), Suspended Solids, Turbidity, PH, Temperature, Iron and Manganese was investigated. The benchmark was the Kenya Bureau (KEBS) and World Health Organization (WHO) Standards for drinking water quality. With respect to microbiological raw water quality improvement, MSF units achieved on average 98% Faecal and 96% Total coliform removal. Results obtained indicate that implementation of MSF in rural communities has the potential to increase access to portable water to the rural populace with a probable consequent decrease in waterborne diseases. With a reduced down time due to illness, more time would be spent in undertaking other economic activities.

  3. Ambient response of a unique performance-based design building with dynamic response modification features

    USGS Publications Warehouse

    Celebi, Mehmet; Huang, Moh; Shakal, Antony; Hooper, John; Klemencic, Ron

    2012-01-01

    A 64-story, performance-based design building with reinforced concrete core shear-walls and unique dynamic response modification features (tuned liquid sloshing dampers and buckling-restrained braces) has been instrumented with a monitoring array of 72 channels of accelerometers. Ambient vibration data recorded are analyzed to identify modes and associated frequencies and damping. The low-amplitude dynamic characteristics are considerably different than those computed from design analyses, but serve as a baseline against which to compare with future strong shaking responses. Such studies help to improve our understanding of the effectiveness of the added features to the building and help improve designs in the future.

  4. Development of Design Technology on Thermal-Hydraulic Performance in Tight-Lattice Rod Bundles: III - Numerical Evaluation of Fluid Mixing Phenomena using Advanced Interface-Tracking Method -

    NASA Astrophysics Data System (ADS)

    Yoshida, Hiroyuki; Nagayoshi, Takuji; Takase, Kazuyuki; Akimoto, Hajime

    Thermal-hydraulic design of the current boiling water reactor (BWR) is performed by correlations with empirical results of actual-size tests. However, for the Innovative Water Reactor for Flexible Fuel Cycle (FLWR) core, an actual size test of an embodiment of its design is required to confirm or modify such correlations. Development of a method that enables the thermal-hydraulic design of nuclear reactors without these actual size tests is desired, because these tests take a long time and entail great cost. For this reason we developed an advanced thermal-hydraulic design method for FLWRs using innovative two-phase flow simulation technology. In this study, detailed Two-Phase Flow simulation code using advanced Interface Tracking method: TPFIT is developed to calculate the detailed information of the two-phase flow. We tried to verify the TPFIT code by comparing it with the 2-channel air-water and steam-water mixing experimental results. The predicted result agrees well the observed results and bubble dynamics through the gap and cross flow behavior could be effectively predicted by the TPFIT code, and pressure difference between fluid channels is responsible for the fluid mixing.

  5. 14 CFR 25.1435 - Hydraulic systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 25.1435 Section 25.1435... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1435 Hydraulic systems. (a) Element design. Each element of the hydraulic system must be designed to: (1) Withstand the proof...

  6. Using observed postconstruction peak discharges to evaluate a hydrologic and hydraulic design model, Boneyard Creek, Champaign and Urbana, Illinois

    USGS Publications Warehouse

    Over, Thomas M.; Soong, David T.; Holmes, Jr., Robert R.

    2011-01-01

    Boneyard Creek—which drains an urbanized watershed in the cities of Champaign and Urbana, Illinois, including part of the University of Illinois at Urbana-Champaign (UIUC) campus—has historically been prone to flooding. Using the Stormwater Management Model (SWMM), a hydrologic and hydraulic model of Boneyard Creek was developed for the design of the projects making up the first phase of a long-term plan for flood control on Boneyard Creek, and the construction of the projects was completed in May 2003. The U.S. Geological Survey, in cooperation with the Cities of Champaign and Urbana and UIUC, installed and operated stream and rain gages in order to obtain data for evaluation of the design-model simulations. In this study, design-model simulations were evaluated by using observed postconstruction precipitation and peak-discharge data. Between May 2003 and September 2008, five high-flow events on Boneyard Creek satisfied the study criterion. The five events were simulated with the design model by using observed precipitation. The simulations were run with two different values of the parameter controlling the soil moisture at the beginning of the storms and two different ways of spatially distributing the precipitation, making a total of four simulation scenarios. The simulated and observed peak discharges and stages were compared at gaged locations along the Creek. The discharge at one of these locations was deemed to be critical for evaluating the design model. The uncertainty of the measured peak discharge was also estimated at the critical location with a method based on linear regression of the stage and discharge relation, an estimate of the uncertainty of the acoustic Doppler velocity meter measurements, and the uncertainty of the stage measurements. For four of the five events, the simulated peak discharges lie within the 95-percent confidence interval of the observed peak discharges at the critical location; the fifth was just outside the upper end of

  7. Joint Feature Extraction and Classifier Design for ECG-Based Biometric Recognition.

    PubMed

    Gutta, Sandeep; Cheng, Qi

    2016-03-01

    Traditional biometric recognition systems often utilize physiological traits such as fingerprint, face, iris, etc. Recent years have seen a growing interest in electrocardiogram (ECG)-based biometric recognition techniques, especially in the field of clinical medicine. In existing ECG-based biometric recognition methods, feature extraction and classifier design are usually performed separately. In this paper, a multitask learning approach is proposed, in which feature extraction and classifier design are carried out simultaneously. Weights are assigned to the features within the kernel of each task. We decompose the matrix consisting of all the feature weights into sparse and low-rank components. The sparse component determines the features that are relevant to identify each individual, and the low-rank component determines the common feature subspace that is relevant to identify all the subjects. A fast optimization algorithm is developed, which requires only the first-order information. The performance of the proposed approach is demonstrated through experiments using the MIT-BIH Normal Sinus Rhythm database. PMID:25680220

  8. The design and implementation of image query system based on color feature

    NASA Astrophysics Data System (ADS)

    Yao, Xu-Dong; Jia, Da-Chun; Li, Lin

    2013-07-01

    ASP.NET technology was used to construct the B/S mode image query system. The theory and technology of database design, color feature extraction from image, index and retrieval in the construction of the image repository were researched. The campus LAN and WAN environment were used to test the system. From the test results, the needs of user queries about related resources were achieved by system architecture design.

  9. Gender Differences in Figural Matrices: The Moderating Role of Item Design Features

    ERIC Educational Resources Information Center

    Arendasy, Martin E.; Sommer, Markus

    2012-01-01

    There is a heated debate on whether observed gender differences in some figural matrices in adults can be attributed to gender differences in inductive reasoning/G[subscript f] or differential item functioning and/or test bias. Based on previous studies we hypothesized that three specific item design features moderate the effect size of the gender…

  10. Design Features and Technology Uncertainties for the Next Generation Nuclear Plant

    SciTech Connect

    John M. Ryskamp; Phil Hildebrandt; Osamu Baba; Ron Ballinger; Robert Brodsky; Hans-Wolfgang Chi; Dennis Crutchfield; Herb Estrada; Jeane-Claude Garnier; Gerald Gordon; Richard Hobbins; Dan Keuter; Marilyn Kray; Philippe Martin; Steve Melancon; Christian Simon; Henry Stone; Robert Varrin; Werner von Lensa

    2004-06-01

    This report presents the conclusions, observations, and recommendations of the Independent Technology Review Group (ITRG) regarding design features and important technology uncertainties associated with very-high-temperature nuclear system concepts for the Next Generation Nuclear Plant (NGNP). The ITRG performed its reviews during the period November 2003 through April 2004.

  11. Experimental Methodology in English Teaching and Learning: Method Features, Validity Issues, and Embedded Experimental Design

    ERIC Educational Resources Information Center

    Lee, Jang Ho

    2012-01-01

    Experimental methods have played a significant role in the growth of English teaching and learning studies. The paper presented here outlines basic features of experimental design, including the manipulation of independent variables, the role and practicality of randomised controlled trials (RCTs) in educational research, and alternative methods…

  12. Neural network classification of autoregressive features from electroencephalogram signals for brain computer interface design

    NASA Astrophysics Data System (ADS)

    Huan, Nai-Jen; Palaniappan, Ramaswamy

    2004-09-01

    In this paper, we have designed a two-state brain-computer interface (BCI) using neural network (NN) classification of autoregressive (AR) features from electroencephalogram (EEG) signals extracted during mental tasks. The main purpose of the study is to use Keirn and Aunon's data to investigate the performance of different mental task combinations and different AR features for BCI design for individual subjects. In the experimental study, EEG signals from five mental tasks were recorded from four subjects. Different combinations of two mental tasks were studied for each subject. Six different feature extraction methods were used to extract the features from the EEG signals: AR coefficients computed with Burg's algorithm, AR coefficients computed with a least-squares (LS) algorithm and adaptive autoregressive (AAR) coefficients computed with a least-mean-square (LMS) algorithm. All the methods used order six applied to 125 data points and these three methods were repeated with the same data but with segmentation into five segments in increments of 25 data points. The multilayer perceptron NN trained by the back-propagation algorithm (MLP-BP) and linear discriminant analysis (LDA) were used to classify the computed features into different categories that represent the mental tasks. We compared the classification performances among the six different feature extraction methods. The results showed that sixth-order AR coefficients with the LS algorithm without segmentation gave the best performance (93.10%) using MLP-BP and (97.00%) using LDA. The results also showed that the segmentation and AAR methods are not suitable for this set of EEG signals. We conclude that, for different subjects, the best mental task combinations are different and proper selection of mental tasks and feature extraction methods are essential for the BCI design.

  13. 3D computations of flow field in a guide vane blading designed by means of 2D model for a low head hydraulic turbine

    NASA Astrophysics Data System (ADS)

    Krzemianowski, Z.; Puzyrewski, R.

    2014-08-01

    The paper presents the main parameters of the flow field behind the guide vane cascade designed by means of 2D inverse problem and following check by means of 3D commercial program ANSYS/Fluent applied for a direct problem. This approach of using different models reflects the contemporary design procedure for non-standardized turbomachinery stage. Depending on the model, the set of conservation equation to be solved differs, although the physical background remains the same. The example of computations for guide vane cascade for a low head hydraulic turbine is presented.

  14. Similarity analysis applied to the design of scaled tests of hydraulic mitigation methods for Tank 241-SY-101

    SciTech Connect

    Liljegren, L.M.

    1993-02-01

    The episodic gas releases from Tank 241-SY-101 (SY-101) pose a potential safety hazard. It is thought that gas releases occur because gases are generated and trapped in layers of settled solids located at the bottom of the tank. This document focuses on issues associated with testing of hydraulic mitigation technologies proposed for SY-101. The basic assumption underlying the concept of hydraulic mitigation is that mobilization or maintained suspension of the solids settled in the bottom of the tank wig prevent gas accumulation. Engineering of hydraulic technologies will require testing to determine the operating parameters required to mobilize the solids and to maintain these solids in suspension. Because full scale testing is extremely expensive (even when possible), scaled tests are needed to assess the merit of the proposed technologies and to provide data for numerical or analytical modeling. This research is conducted to support testing and evaluation of proposed hydraulic mitigation concepts only. The work here is oriented towards determining the jet velocities, nozzle sizes, and other operating parameters required to mobilize the settled solids in SY- 101 and maintain them in suspension.

  15. Influence of Hydraulic Design on Stability and on Pressure Pulsations in Francis Turbines at Overload, Part Load and Deep Part Load based on Numerical Simulations and Experimental Model Test Results

    NASA Astrophysics Data System (ADS)

    Magnoli, M. V.; Maiwald, M.

    2014-03-01

    Francis turbines have been running more and more frequently in part load conditions, in order to satisfy the new market requirements for more dynamic and flexible energy generation, ancillary services and grid regulation. The turbines should be able to be operated for longer durations with flows below the optimum point, going from part load to deep part load and even speed-no-load. These operating conditions are characterised by important unsteady flow phenomena taking place at the draft tube cone and in the runner channels, in the respective cases of part load and deep part load. The current expectations are that new Francis turbines present appropriate hydraulic stability and moderate pressure pulsations at overload, part load, deep part load and speed-no-load with high efficiency levels at normal operating range. This study presents series of investigations performed by Voith Hydro with the objective to improve the hydraulic stability of Francis turbines at overload, part load and deep part load, reduce pressure pulsations and enlarge the know-how about the transient fluid flow through the turbine at these challenging conditions. Model test measurements showed that distinct runner designs were able to influence the pressure pulsation level in the machine. Extensive experimental investigations focused on the runner deflector geometry, on runner features and how they could reduce the pressure oscillation level. The impact of design variants and machine configurations on the vortex rope at the draft tube cone at overload and part load and on the runner channel vortex at deep part load were experimentally observed and evaluated based on the measured pressure pulsation amplitudes. Numerical investigations were employed for improving the understanding of such dynamic fluid flow effects. As example for the design and experimental investigations, model test observations and pressure pulsation curves for Francis machines in mid specific speed range, around nqopt = 50 min

  16. Multiple approaches to valuation of conservation design and low-impact development features in residential subdivisions.

    PubMed

    Bowman, Troy; Tyndall, John C; Thompson, Janette; Kliebenstein, James; Colletti, Joe P

    2012-08-15

    Residents, developers and civic officials are often faced with difficult decisions about appropriate land uses in and around metropolitan boundaries. Urban expansion brings with it the potential for negative environmental impacts, but there are alternatives, such as conservation subdivision design (CSD) or low-impact development (LID), which offer the possibility of mitigating some of these effects at the development site. Many urban planning jurisdictions across the Midwest do not currently have any examples of these designs and lack information to identify public support or barriers to use of these methods. This is a case study examining consumer value for conservation and low-impact design features in one housing market by using four different valuation techniques to estimate residents' willingness to pay for CSD and LID features in residential subdivisions. A contingent valuation survey of 1804 residents in Ames, IA assessed familiarity with and perceptions of subdivision development and used an ordered value approach to estimate willingness to pay for CSD and LID features. A majority of residents were not familiar with CSD or LID practices. Residents indicated a willingness to pay for most CSD and LID features with the exception of clustered housing. Gender, age, income, familiarity with LID practices, perceptions of attractiveness of features and the perceived effect of CSD and LID features on ease of future home sales were important factors influencing residents' willingness to pay. A hypothetical referendum measured willingness to pay for tax-funded conservation land purchases and estimated that a property tax of around $50 would be the maximum increase that would pass. Twenty-seven survey respondents participated in a subsequent series of experimental real estate negotiations that used an experimental auction mechanism to estimate willingness to pay for CSD and LID features. Participants indicated that clustered housing (with interspersed preserved forest

  17. Water Treatment Technology - Hydraulics.

    ERIC Educational Resources Information Center

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on hydraulics provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: head loss in pipes in series, function loss in…

  18. Current and anticipated uses of thermal-hydraulic codes in NFI

    SciTech Connect

    Tsuda, K.; Takayasu, M.

    1997-07-01

    This paper presents the thermal-hydraulic codes currently used in NFI for the LWR fuel development and licensing application including transient and design basis accident analyses of LWR plants. The current status of the codes are described in the context of code capability, modeling feature, and experience of code application related to the fuel development and licensing. Finally, the anticipated use of the future thermal-hydraulic code in NFI is briefly given.

  19. Design features of the radioactive Liquid-Fed Ceramic Melter system

    SciTech Connect

    Holton, L.K. Jr.

    1985-06-01

    During 1983, the Pacific Northwest Laboratory (PNL), at the request of the Department of Energy (DOE), undertook a program with the principal objective of testing the Liquid-Fed Ceramic Melter (LFCM) process in actual radioactive operations. This activity, termed the Radioactive LFCM (RLFCM) Operations is being conducted in existing shielded hot-cell facilities in B-Cell of the 324 Building, 300 Area, located at Hanford, Washington. This report summarizes the design features of the RLFCM system. These features include: a waste preparation and feed system which uses pulse-agitated waste preparation tanks for waste slurry agitation and an air displacement slurry pump for transferring waste slurries to the LFCM; a waste vitrification system (LFCM) - the design features, design approach, and reasoning for the design of the LFCM are described; a canister-handling turntable for positioning canisters underneath the RLFCM discharge port; a gamma source positioning and detection system for monitoring the glass fill level of the product canisters; and a primary off-gas treatment system for removing the majority of the radionuclide contamination from the RLFCM off gas. 8 refs., 48 figs., 6 tabs.

  20. Mutagenicity of smoke condensates from Canadian cigarettes with different design features.

    PubMed

    Mladjenovic, Nemanja; Maertens, Rebecca M; White, Paul A; Soo, Evelyn C

    2014-01-01

    There is currently limited knowledge regarding the impact of different cigarette designs on the toxicological properties of cigarette smoke condensate (CSC). This study used the Salmonella Mutagenicity Assay to examine the mutagenic activity of mainstream CSCs from 11 commercial Canadian cigarette brands with different design features or tobacco blend. The brands were selected to include design features that are common for cigarettes sold in the Canadian market, as well as cigarettes with alternate filters (charcoal or MicroBlue™), the super slim design, and cigarettes containing mixed blends of different tobacco types. CSCs were obtained using the International Organization for Standardization (ISO) and Health Canada Intense (HCI) smoking regimes, and mutagenic activity was assessed using Salmonella strains TA98, YG1041 and YG5185. Comparisons of the commercial brands to the Kentucky 3R4F, the Canadian Monitor 8 reference and a Canadian best seller revealed no significant reduction in CSC mutagenicity for cigarettes with alternate filters. However, the super slim design did afford some reduction in mutagenic potency. Nevertheless, since the study did not attempt to evaluate the impact of the cigarette designs on human health at the individual or population level, the super slim cigarettes cannot be considered 'reduced-harm' cigarettes. PMID:24321849

  1. Emergent features and perceptual objects: re-examining fundamental principles in analogical display design.

    PubMed

    Holt, Jerred; Bennett, Kevin B; Flach, John M

    2015-01-01

    Two sets of design principles for analogical visual displays, based on the concepts of emergent features and perceptual objects, are described. An interpretation of previous empirical findings for three displays (bar graph, polar graphic, alphanumeric) is provided from both perspectives. A fourth display (configural coordinate) was designed using principles of ecological interface design (i.e. direct perception). An experiment was conducted to evaluate performance (accuracy and latency of state identification) with these four displays. Numerous significant effects were obtained and a clear rank ordering of performance emerged (from best to worst): configural coordinate, bar graph, alphanumeric and polar graphic. These findings are consistent with principles of design based on emergent features; they are inconsistent with principles based on perceptual objects. Some limitations of the configural coordinate display are discussed and a redesign is provided. Practitioner Summary: Principles of ecological interface design, which emphasise the quality of very specific mappings between domain, display and observer constraints, are described; these principles are applicable to the design of all analogical graphical displays. PMID:26218496

  2. Teledesic Global Wireless Broadband Network: Space Infrastructure Architecture, Design Features and Technologies

    NASA Technical Reports Server (NTRS)

    Stuart, James R.

    1995-01-01

    The Teledesic satellites are a new class of small satellites which demonstrate the important commercial benefits of using technologies developed for other purposes by U.S. National Laboratories. The Teledesic satellite architecture, subsystem design features, and new technologies are described. The new Teledesic satellite manufacturing, integration, and test approaches which use modern high volume production techniques and result in surprisingly low space segment costs are discussed. The constellation control and management features and attendant software architecture features are addressed. After briefly discussing the economic and technological impact on the USA commercial space industries of the space communications revolution and such large constellation projects, the paper concludes with observations on the trend toward future system architectures using networked groups of much smaller satellites.

  3. 14 CFR 27.1435 - Hydraulic systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Hydraulic systems. 27.1435 Section 27.1435... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1435 Hydraulic systems. (a) Design. Each hydraulic system and its elements must withstand, without yielding, any structural loads...

  4. 14 CFR 27.1435 - Hydraulic systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Hydraulic systems. 27.1435 Section 27.1435... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1435 Hydraulic systems. (a) Design. Each hydraulic system and its elements must withstand, without yielding, any structural loads...

  5. 14 CFR 27.1435 - Hydraulic systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Hydraulic systems. 27.1435 Section 27.1435... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1435 Hydraulic systems. (a) Design. Each hydraulic system and its elements must withstand, without yielding, any structural loads...

  6. 14 CFR 27.1435 - Hydraulic systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Hydraulic systems. 27.1435 Section 27.1435... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1435 Hydraulic systems. (a) Design. Each hydraulic system and its elements must withstand, without yielding, any structural loads...

  7. 14 CFR 29.1435 - Hydraulic systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Hydraulic systems. 29.1435 Section 29.1435 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1435 Hydraulic systems. (a) Design. Each hydraulic system...

  8. 14 CFR 27.1435 - Hydraulic systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 27.1435 Section 27.1435... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1435 Hydraulic systems. (a) Design. Each hydraulic system and its elements must withstand, without yielding, any structural loads...

  9. Innovative wet FGD design features at Kentucky Utilities` Ghent Generating Station, Unit 1

    SciTech Connect

    Ruppert, M.A.; Mitchell, D.

    1995-06-01

    To meet Phase I requirements of the 1990 Federal Clean Air Act Amendments, Kentucky Utilities (KU) elected to retrofit a wet limestone, forced oxidized flue gas desulfurization (FGD) system on their Ghent Generating Station, Unit 1 (500 MW). This FGD system has been designed with several innovative features to enhance SO{sub 2} removal and reduce overall project cost. Organic acids have been incorporated to increase SO{sub 2} removal from 90% to 95%. Also, this Phase I project is designed to accommodate a second FGD to be built at the same site. This will allow both units to share common spare equipment, including a common spare absorber. A wet gypsum stack-out pond is being used in lieu of dewatering equipment. This paper discusses these innovative features from both a performance and an economic standpoint.

  10. The effects of sign design features on bicycle pictorial symbols for bicycling facility signs.

    PubMed

    Oh, Kyunghui; Rogoff, Aaron; Smith-Jackson, Tonya

    2013-11-01

    The inanimate bicycle symbol has long been used to indicate the animate activity of bicycling facility signs. In contrast, either the inanimate bicycle symbol or the animate bicycle symbol has been used interchangeably for the standard pavement symbols in bike lanes. This has led to confusion among pedestrians and cyclists alike. The purpose of this study was to examine two different designs (inanimate symbol vs. animate symbol) involved in the evaluation of perceived preference and glance legibility, and investigate sign design features on bicycle pictorial symbols. Thirty-five participants compared current bicycle signs (inanimate symbols) to alternative designs (animate symbols) in a controlled laboratory setting. The results indicated that the alternative designs (animate symbols) showed better performance in both preference and glance legibility tests. Conceptual compatibility, familiarity, and perceptual affordances were found to be important factors as well. PMID:23623234

  11. Advanced Performance Hydraulic Wind Energy

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Bruce, Allan; Lam, Adrienne S.

    2013-01-01

    The Jet Propulsion Laboratory, California Institute of Technology, has developed a novel advanced hydraulic wind energy design, which has up to 23% performance improvement over conventional wind turbine and conventional hydraulic wind energy systems with 5 m/sec winds. It also has significant cost advantages with levelized costs equal to coal (after carbon tax rebate). The design is equally applicable to tidal energy systems and has passed preliminary laboratory proof-of-performance tests, as funded by the Department of Energy.

  12. AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT III, AUTOMATIC TRANSMISSIONS--HYDRAULICS (PART I).

    ERIC Educational Resources Information Center

    Human Engineering Inst., Cleveland, OH.

    THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO INTRODUCE BASIC HYDRAULIC PRINCIPLES AND PROVIDE AN UNDERSTANDING OF HYDRAULIC TRANSMISSIONS USED IN DIESEL POWERED VEHICLES. TOPICS ARE WHY USE HYDRAULICS, REVIEWING BASIC PHYSICS LAWS IN RELATION TO HYDRAULICS, UNDERSTANDING THE HYDRAULIC SYSTEM, AND DEVELOPING A BASIC HYDRAULIC SYSTEM. THE MODULE…

  13. Green Infrastructure Design Based on Spatial Conservation Prioritization and Modeling of Biodiversity Features and Ecosystem Services.

    PubMed

    Snäll, Tord; Lehtomäki, Joona; Arponen, Anni; Elith, Jane; Moilanen, Atte

    2016-02-01

    There is high-level political support for the use of green infrastructure (GI) across Europe, to maintain viable populations and to provide ecosystem services (ES). Even though GI is inherently a spatial concept, the modern tools for spatial planning have not been recognized, such as in the recent European Environment Agency (EEA) report. We outline a toolbox of methods useful for GI design that explicitly accounts for biodiversity and ES. Data on species occurrence, habitats, and environmental variables are increasingly available via open-access internet platforms. Such data can be synthesized by statistical species distribution modeling, producing maps of biodiversity features. These, together with maps of ES, can form the basis for GI design. We argue that spatial conservation prioritization (SCP) methods are effective tools for GI design, as the overall SCP goal is cost-effective allocation of conservation efforts. Corridors are currently promoted by the EEA as the means for implementing GI design, but they typically target the needs of only a subset of the regional species pool. SCP methods would help to ensure that GI provides a balanced solution for the requirements of many biodiversity features (e.g., species, habitat types) and ES simultaneously in a cost-effective manner. Such tools are necessary to make GI into an operational concept for combating biodiversity loss and promoting ES. PMID:26395184

  14. Green Infrastructure Design Based on Spatial Conservation Prioritization and Modeling of Biodiversity Features and Ecosystem Services

    NASA Astrophysics Data System (ADS)

    Snäll, Tord; Lehtomäki, Joona; Arponen, Anni; Elith, Jane; Moilanen, Atte

    2016-02-01

    There is high-level political support for the use of green infrastructure (GI) across Europe, to maintain viable populations and to provide ecosystem services (ES). Even though GI is inherently a spatial concept, the modern tools for spatial planning have not been recognized, such as in the recent European Environment Agency (EEA) report. We outline a toolbox of methods useful for GI design that explicitly accounts for biodiversity and ES. Data on species occurrence, habitats, and environmental variables are increasingly available via open-access internet platforms. Such data can be synthesized by statistical species distribution modeling, producing maps of biodiversity features. These, together with maps of ES, can form the basis for GI design. We argue that spatial conservation prioritization (SCP) methods are effective tools for GI design, as the overall SCP goal is cost-effective allocation of conservation efforts. Corridors are currently promoted by the EEA as the means for implementing GI design, but they typically target the needs of only a subset of the regional species pool. SCP methods would help to ensure that GI provides a balanced solution for the requirements of many biodiversity features (e.g., species, habitat types) and ES simultaneously in a cost-effective manner. Such tools are necessary to make GI into an operational concept for combating biodiversity loss and promoting ES.

  15. Design Features and Commissioning of the Versatile Experiment Spherical Torus (VEST) at Seoul National University

    NASA Astrophysics Data System (ADS)

    J. Chung, K.; H. An, Y.; K. Jung, B.; Y. Lee, H.; C., Sung; S. Na, Y.; S. Hahm, T.; S. Hwang, Y.

    2013-03-01

    A new spherical torus called VEST (Versatile Experiment Spherical Torus) is designed, constructed and successfully commissioned at Seoul National University. A unique design feature of the VEST is two partial solenoid coils installed at both vertical ends of a center stack, which can provide sufficient magnetic fluxes to initiate tokamak plasmas while keeping a low aspect ratio configuration in the central region. According to initial double null merging start-up scenario using the partial solenoid coils, appropriate power supplies for driving a toroidal field coil, outer poloidal field coils, and the partial solenoid coils are fabricated and successfully commissioned. For reliable start-up, a pre-ionization system with two cost-effective homemade magnetron power supplies is also prepared. In addition, magnetic and spectroscopic diagnostics with appropriate data acquisition and control systems are well prepared for initial operation of the device. The VEST is ready for tokamak plasma operation by completing and commissioning most of the designed components.

  16. Acoustical features of two Mayan monuments at Chichen Itza: Accident or design?

    NASA Astrophysics Data System (ADS)

    Lubman, David

    2002-11-01

    Chichen Itza dominated the early postclassic Maya world, ca. 900-1200 C.E. Two of its colossal monuments, the Great Ball Court and the temple of Kukulkan, reflect the sophisticated, hybrid culture of a Mexicanized Maya civilization. The architecture seems intended for ceremony and ritual drama. Deducing ritual practices will advance the understanding of a lost civilization, but what took place there is largely unknown. Perhaps acoustical science can add value. Unexpected and unusual acoustical features can be interpreted as intriguing clues or irrelevant accidents. Acoustical advocates believe that, when combined with an understanding of the Maya worldview, acoustical features can provide unique insights into how the Maya designed and used theater spaces. At Chichen Itza's monuments, sound reinforcement features improve rulers and priests ability to address large crowds, and Ball Court whispering galleries permit speech communication over unexpectedly large distances. Handclaps at Kukulkan stimulate chirps that mimic a revered bird (''Kukul''), thus reinforcing cultic beliefs. A ball striking playing field wall stimulates flutter echoes at the Great Ball Court; their strength and duration arguably had dramatic, mythic, and practical significance. Interpretations of the possible mythic, magic, and political significance of sound phenomena at these Maya monuments strongly suggests intentional design.

  17. Some novel design features of the LBL metal vapor vacuum arc ion sources

    SciTech Connect

    MacGill, R.A.; Brown, I.G.; Galvin, J.E.

    1989-06-01

    The family of MEVVA (metal vapor vacuum arc) high current metal ion sources developed at LBL over the past several years has grown to include a number of different source versions with a wide range of some of the design and operational parameters. The MicroMEVVA source is a particularly compact version, about 2 cm diameter and 10 cm long, while the MEVVA IV weighs some 30 kG. MEVVAs IV and V incorporate multiple cathode assemblies (16 and 18 separate cathodes, respectively), and the operating cathode can be switched rapidly and without down-time. The new MEVVA V embodiment is quite compact considering its broad beam (10 cm), high voltage (100 kV) and multiple cathode features. The large-area extractor grids used in the MEVVA V were fabricated using a particularly simple technique, and they are clamped into position and so can be changed simply and quickly. The electrical system used to drive the arc is particularly simple and incorporates several attractive features. In this paper we review and describe a number of the mechanical and electrical design features that have been developed for these sources. 9 refs., 5 figs.

  18. Housing Stakeholder Preferences for the "Soft" Features of Sustainable and Healthy Housing Design in the UK.

    PubMed

    Prochorskaite, Agne; Couch, Chris; Malys, Naglis; Maliene, Vida

    2016-01-01

    It is widely recognised that the quantity and sustainability of new homes in the UK need to increase. However, it is important that sustainable housing is regarded holistically, and not merely in environmental terms, and incorporates elements that enhance the quality of life, health and well-being of its users. This paper focuses on the "soft" features of sustainable housing, that is, the non-technological components of sustainable housing and neighbourhood design that can impact occupants' health and well-being. Aims of the study are to ascertain the relative level of importance that key housing stakeholders attach to these features and to investigate whether the opinions of housing users and housing providers are aligned with regards to their importance. An online survey was carried out to gauge the level of importance that the key stakeholders, such as housing users, local authorities, housing associations, and developers (n = 235), attach to these features. Results revealed that while suitable indoor space was the feature regarded as most important by all stakeholders, there were also a number of disparities in opinion between housing users and housing providers (and among the different types of providers). This implies a scope for initiatives to achieve a better alignment between housing users and providers. PMID:26751465

  19. Design Features of Drug-Drug Interaction Trials Between Antivirals and Oral Contraceptives.

    PubMed

    Ayala, Ruben C; Arya, Vikram; Younis, Islam R

    2016-05-01

    The aim of this work was to explore the major design features of drug-drug interaction trials between antiviral medications (AVs) and oral contraceptives (OCs). Information on these trials (n = 27) was collected from approved drug labels and clinical pharmacology reviews conducted by the U.S. Food and Drug Administration. The primary objective of all trials was to evaluate changes in OC exposure following the coadministration of AVs. In addition, an evaluation of potential pharmacodynamic interaction was performed in 10 of these trials. Twenty-two trials were open label with a fixed-sequence design, and 5 trials used a double-blind crossover design. The trials were conducted using one, two, or three 28-day ovulatory cycles in 10, 8, and 9 trials, respectively. Only 1 trial enrolled HIV-infected women. The median number of women in a trial was 20 (range, 12 to 52). Norethindrone/ethinyl estradiol (EE) combination was the most commonly used OC (n = 16, 59%) followed by norgestimate/EE (n = 9, 33%). Labeling recommendations were based on exposure changes in 25 cases and on safety observations in the trial in 2 cases. In conclusion, a wide variety of trial designs was used, and there is no preferred design. The answer to the exposure question can be achieved using multiple designs. PMID:26384089

  20. System requirements and design features of Space Station Remote Manipulator System mechanisms

    NASA Technical Reports Server (NTRS)

    Kumar, Rajnish; Hayes, Robert

    1991-01-01

    The Space Station Remote Manipulator System (SSRMS) is a long robotic arm for handling large objects/payloads on the International Space Station Freedom. The mechanical components of the SSRMS include seven joints, two latching end effectors (LEEs), and two boom assemblies. The joints and LEEs are complex aerospace mechanisms. The system requirements and design features of these mechanisms are presented. All seven joints of the SSRMS have identical functional performance. The two LEES are identical. This feature allows either end of the SSRMS to be used as tip or base. As compared to the end effector of the Shuttle Remote Manipulator System, the LEE has a latch and umbilical mechanism in addition to the snare and rigidize mechanisms. The latches increase the interface preload and allow large payloads (up to 116,000 Kg) to be handled. The umbilical connectors provide power, data, and video signal transfer capability to/from the SSRMS.

  1. Design of vector quantizer for image compression using self-organizing feature map and surface fitting.

    PubMed

    Laha, Arijit; Pal, Nikhil R; Chanda, Bhabatosh

    2004-10-01

    We propose a new scheme of designing a vector quantizer for image compression. First, a set of codevectors is generated using the self-organizing feature map algorithm. Then, the set of blocks associated with each code vector is modeled by a cubic surface for better perceptual fidelity of the reconstructed images. Mean-removed vectors from a set of training images is used for the construction of a generic codebook. Further, Huffman coding of the indices generated by the encoder and the difference-coded mean values of the blocks are used to achieve better compression ratio. We proposed two indices for quantitative assessment of the psychovisual quality (blocking effect) of the reconstructed image. Our experiments on several training and test images demonstrate that the proposed scheme can produce reconstructed images of good quality while achieving compression at low bit rates. Index Terms-Cubic surface fitting, generic codebook, image compression, self-organizing feature map, vector quantization. PMID:15462140

  2. Iodine atoms: a new molecular feature for the design of potent transthyretin fibrillogenesis inhibitors.

    PubMed

    Mairal, Teresa; Nieto, Joan; Pinto, Marta; Almeida, Maria Rosário; Gales, Luis; Ballesteros, Alfredo; Barluenga, José; Pérez, Juan J; Vázquez, Jesús T; Centeno, Nuria B; Saraiva, Maria Joao; Damas, Ana M; Planas, Antoni; Arsequell, Gemma; Valencia, Gregorio

    2009-01-01

    The thyroid hormone and retinol transporter protein known as transthyretin (TTR) is in the origin of one of the 20 or so known amyloid diseases. TTR self assembles as a homotetramer leaving a central hydrophobic channel with two symmetrical binding sites. The aggregation pathway of TTR into amiloid fibrils is not yet well characterized but in vitro binding of thyroid hormones and other small organic molecules to TTR binding channel results in tetramer stabilization which prevents amyloid formation in an extent which is proportional to the binding constant. Up to now, TTR aggregation inhibitors have been designed looking at various structural features of this binding channel others than its ability to host iodine atoms. In the present work, greatly improved inhibitors have been designed and tested by taking into account that thyroid hormones are unique in human biochemistry owing to the presence of multiple iodine atoms in their molecules which are probed to interact with specific halogen binding domains sitting at the TTR binding channel. The new TTR fibrillogenesis inhibitors are based on the diflunisal core structure because diflunisal is a registered salicylate drug with NSAID activity now undergoing clinical trials for TTR amyloid diseases. Biochemical and biophysical evidence confirms that iodine atoms can be an important design feature in the search for candidate drugs for TTR related amyloidosis. PMID:19125186

  3. Iodine Atoms: A New Molecular Feature for the Design of Potent Transthyretin Fibrillogenesis Inhibitors

    PubMed Central

    Pinto, Marta; Almeida, Maria Rosário; Gales, Luis; Ballesteros, Alfredo; Barluenga, José; Pérez, Juan J.; Vázquez, Jesús T.; Centeno, Nuria B.; Saraiva, Maria Joao; Damas, Ana M.; Planas, Antoni; Arsequell, Gemma; Valencia, Gregorio

    2009-01-01

    The thyroid hormone and retinol transporter protein known as transthyretin (TTR) is in the origin of one of the 20 or so known amyloid diseases. TTR self assembles as a homotetramer leaving a central hydrophobic channel with two symmetrical binding sites. The aggregation pathway of TTR into amiloid fibrils is not yet well characterized but in vitro binding of thyroid hormones and other small organic molecules to TTR binding channel results in tetramer stabilization which prevents amyloid formation in an extent which is proportional to the binding constant. Up to now, TTR aggregation inhibitors have been designed looking at various structural features of this binding channel others than its ability to host iodine atoms. In the present work, greatly improved inhibitors have been designed and tested by taking into account that thyroid hormones are unique in human biochemistry owing to the presence of multiple iodine atoms in their molecules which are probed to interact with specific halogen binding domains sitting at the TTR binding channel. The new TTR fibrillogenesis inhibitors are based on the diflunisal core structure because diflunisal is a registered salicylate drug with NSAID activity now undergoing clinical trials for TTR amyloid diseases. Biochemical and biophysical evidence confirms that iodine atoms can be an important design feature in the search for candidate drugs for TTR related amyloidosis. PMID:19125186

  4. Chemometric design to explore pharmacophore features of BACE inhibitors for controlling Alzheimer's disease.

    PubMed

    Hossain, Tabassum; Mukherjee, Arup; Saha, Achintya

    2015-02-01

    The β-amyloid precursor protein cleavage enzyme (BACE) has been conceived to be an attractive therapeutic target to control Alzheimer's disease (AD). Validated ligand-based pharmacophore mapping was combined with 3D QSAR modeling approaches that include CoMFA, CoMSIA and HQSAR techniques to identify structural and physico-chemical requirements for a potential BACE inhibitor using a database containing 980 structurally diverse compounds, assembled from different reports. A structure-based docking technique was also used to validate the features obtained from the ligand-based models, which were further used to screen the database of compounds designed by a de novo approach. Contour maps of 3D QSAR models, CoMFA (R(2) = 0.880, se = 0.402, Q(2) = 0.596, Rpred(2) = 0.713,) and CoMSIA (R(2) = 0.903, se = 0.362, Q(2) = 0.578, Rpred(2) = 0.715), and a pharmacophore space model (R(2) = 0.833, rmsd = 1.578, Q(2) = 0.845, Rpred(2) = 0. 764) depict that the models are robust and provide an explanation of the important features such as steric, electrostatic, hydrophobic, positive ionization, hydrogen bond acceptor and donor properties, which play important roles for interaction with the receptor site cavity. The HQSAR study (R(2) = 0.823, se = 0.488, Q(2) = 0.823, Rpred(2) = 0.768) and de novo design, which generate new fragments, illustrated the important molecular fingerprints for inhibition. The docking study elucidated the important interactions between the amino acid residues (Gly11, Thr72, Asp228, Gly230, Thr231, Arg235) at the catalytic site of the receptor and the ligand, indicating the structural requirements of the inhibitors. The de novo designed molecules were further screened for ADMET properties, and ligand-receptor interactions of the top hits were analysed by molecular docking to explore pharmacophore features of BACE inhibitors. PMID:25435329

  5. Design Features and Capabilities of the First Materials Science Research Rack

    NASA Technical Reports Server (NTRS)

    Pettigrew, P. J.; Lehoczky, S. L.; Cobb, S. D.; Holloway, T.; Kitchens, L.

    2003-01-01

    The First Materials Science Research Rack (MSRR-1) aboard the International Space Station (ISS) will offer many unique capabilities and design features to facilitate a wide range of materials science investigations. The initial configuration of MSRR-1 will accommodate two independent Experiment Modules (EMS) and provide the capability for simultaneous on-orbit processing. The facility will provide the common subsystems and interfaces required for the operation of experiment hardware and accommodate telescience capabilities. MSRR1 will utilize an International Standard Payload Rack (ISPR) equipped with an Active Rack Isolation System (ARIS) for vibration isolation of the facility.

  6. DESIGN SAFETY FEATURES OF THE BNL HIGH-TEMPERATURE COMBUSTION FACILITY

    SciTech Connect

    GINSBERG,T.; CICCARELLI,G.; BOCCIO,J.

    2000-06-11

    The Brookhaven National Laboratory (BNL) High-Temperature Combustion Facility (HTCF) was used to perform hydrogen deflagration and detonation experiments at temperatures to 650 K. Safety features that were designed to ensure safe and reliable operation of the experimental program are described. Deflagration and detonation experiments have been conducted using mixtures of hydrogen, air, and steam. Detonation cell size measurements were made as a function of mixture composition and thermodynamic gas conditions. Deflagration-to-detonation transition experiments were also conducted. Results of the experimental program are presented, and implications with respect to hydrogen safety are discussed.

  7. Effect of design features on performance of a double-annular ram-induction combustor

    NASA Technical Reports Server (NTRS)

    Schultz, D. F.

    1975-01-01

    An extensive test program was undertaken to determine the effect of many design features such as the size and number of air scoops, and the type of diffuser airflow distribution to use to optimize performance of a double-annular ram-induction combustor of 94 cm outer diameter. Six combustor configurations were tested. It was found that a snouted double annular combustor built with 256 ram-induction air scoops with a combustor open area giving a total pressure loss of 5.0 percent at a diffuser inlet Mach number of 0.25 gave the best overall performance of the configurations tested.

  8. Design features of implants for direct skeletal attachment of limb prostheses

    PubMed Central

    Pitkin, M.

    2013-01-01

    In direct skeletal attachment (DSA) of limb prostheses, a construct is implanted into an amputee’s residuum bone and protrudes out of the residuum’s skin. This technology represents an alternative to traditional suspension of prostheses via various socket systems, with clear indications when the sockets cannot be properly fitted. Contemporary DSA was invented in the 1990s, and several implant systems have been introduced since then. The current review is intended to compare the design features of implants for DSA whose use in humans or in animal studies has been reported in the literature. PMID:23554122

  9. Feature, design intention and constraint preservation for direct modeling of 3D freeform surfaces

    NASA Astrophysics Data System (ADS)

    Fu, Luoting; Kara, Levent Burak; Shimada, Kenji

    2012-06-01

    Direct modeling has recently emerged as a suitable approach for 3D free-form shape modeling in industrial design. It has several advantages over the conventional, parametric modeling techniques, including natural user interactions, as well as the underlying, automatic feature-preserving shape deformation algorithms. However, current direct modeling packages still lack several capabilities critical for product design, such as managing aesthetic design intentions, and enforcing dimensional, geometric constraints. In this paper, we describe a novel 3D surface editing system capable of jointly accommodating aesthetic design intentions expressed in the form of surface painting and color-coded annotations, as well as engineering constraints expressed as dimensions. The proposed system is built upon differential coordinates and constrained least squares, and is intended for conceptual design that involves frequent shape tuning and explorations. We also provide an extensive review of the state-of-the-art direct modeling approaches for 3D mesh-based, freeform surfaces, with an emphasis on the two broad categories of shape deformation algorithms developed in the relevant field of geometric modeling. [Figure not available: see fulltext.

  10. Design of Unstructured Adaptive (UA) NAS Parallel Benchmark Featuring Irregular, Dynamic Memory Accesses

    NASA Technical Reports Server (NTRS)

    Feng, Hui-Yu; VanderWijngaart, Rob; Biswas, Rupak; Biegel, Bryan (Technical Monitor)

    2001-01-01

    We describe the design of a new method for the measurement of the performance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. The method involves the solution of a stylized heat transfer problem on an unstructured, adaptive grid. A Spectral Element Method (SEM) with an adaptive, nonconforming mesh is selected to discretize the transport equation. The relatively high order of the SEM lowers the fraction of wall clock time spent on inter-processor communication, which eases the load balancing task and allows us to concentrate on the memory accesses. The benchmark is designed to be three-dimensional. Parallelization and load balance issues of a reference implementation will be described in detail in future reports.

  11. Design of free patterns of nanocrystals with ad hoc features via templated dewetting

    SciTech Connect

    Aouassa, M.; Berbezier, I.; Favre, L.; Ronda, A.; Bollani, M.; Sordan, R.; Delobbe, A.; Sudraud, P.

    2012-07-02

    Design of monodisperse ultra-small nanocrystals (NCs) into large scale patterns with ad hoc features is demonstrated. The process makes use of solid state dewetting of a thin film templated through alloy liquid metal ion source focused ion beam (LMIS-FIB) nanopatterning. The solid state dewetting initiated at the edges of the patterns controllably creates the ordering of NCs with ad hoc placement and periodicity. The NC size is tuned by varying the nominal thickness of the film while their position results from the association of film retraction from the edges of the lay out and Rayleigh-like instability. The use of ultra-high resolution LMIS-FIB enables to produce monocrystalline NCs with size, periodicity, and placement tunable as well. It provides routes for the free design of nanostructures for generic applications in nanoelectronics.

  12. HYDRAULIC STUDIES AND CLEANING EVALUATIONS OF ULTRAVIOLET DISINFECTION UNITS

    EPA Science Inventory

    Various types of operating ultraviolet disinfection reactor designs were evaluated for hydraulic characteristics and cleaning requirements. The fluorocarbon polymer tube designs promote plug-flow behavior because of their relatively high length-to-diameter ratio. Hydraulic evalua...

  13. Innovative and Advanced Coupled Neutron Transport and Thermal Hydraulic Method (Tool) for the Design, Analysis and Optimization of VHTR/NGNP Prismatic Reactors

    SciTech Connect

    Rahnema, Farzad; Garimeela, Srinivas; Ougouag, Abderrafi; Zhang, Dingkang

    2013-11-29

    This project will develop a 3D, advanced coarse mesh transport method (COMET-Hex) for steady- state and transient analyses in advanced very high-temperature reactors (VHTRs). The project will lead to a coupled neutronics and thermal hydraulic (T/H) core simulation tool with fuel depletion capability. The computational tool will be developed in hexagonal geometry, based solely on transport theory without (spatial) homogenization in complicated 3D geometries. In addition to the hexagonal geometry extension, collaborators will concurrently develop three additional capabilities to increase the code’s versatility as an advanced and robust core simulator for VHTRs. First, the project team will develop and implement a depletion method within the core simulator. Second, the team will develop an elementary (proof-of-concept) 1D time-dependent transport method for efficient transient analyses. The third capability will be a thermal hydraulic method coupled to the neutronics transport module for VHTRs. Current advancements in reactor core design are pushing VHTRs toward greater core and fuel heterogeneity to pursue higher burn-ups, efficiently transmute used fuel, maximize energy production, and improve plant economics and safety. As a result, an accurate and efficient neutron transport, with capabilities to treat heterogeneous burnable poison effects, is highly desirable for predicting VHTR neutronics performance. This research project’s primary objective is to advance the state of the art for reactor analysis.

  14. Preliminary design features of the RASCAL - A NASA/Army rotorcraft in-flight simulator

    NASA Technical Reports Server (NTRS)

    Aiken, Edwin W.; Jacobsen, Robert A.; Eshow, Michelle M.; Hindson, William S.; Doane, Douglas H.

    1992-01-01

    Salient design features of a new NASA/Army research rotorcraft - the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) - are described. Using a UH-60A Black Hawk helicopter as a baseline vehicle, the RASCAL will be a flying laboratory capable of supporting the research requirements of major NASA and Army guidance, control, and display research programs. The paper describes the research facility requirements of these programs together with other critical constraints on the design of the research system, including safety-of-flight. Research program schedules demand a phased development approach, wherein specific research capability milestones are met and flight research projects are flown throughout the complete development cycle of the RASCAL. This development approach is summarized, and selected features of the research system are described. The research system includes a full-authority, programmable, fault-tolerant/fail-safe, fly-by-wire flight control system and a real-time obstacle detection and avoidance system which will generate low-latitude guidance commands to the pilot on a wide field-of-view, color helmet-mounted display.

  15. Dynamic impact and pressure analysis of the insensitive munitions container PA103 with modified design features

    SciTech Connect

    Handy, K.D.

    1993-06-01

    This report presents analytical analyses of the insensitive munitions container PA103, with modified design features for a static internal pressure of 500 psi and for a dynamic impact resulting from a 7-ft free fall onto a rigid surface. The modified design features addressed by the analyses were the inclusion of a score pattern on the container cylindrical body and a plastic plate (fuse) sandwiched between metal flanges on the container end. The objectives of both the pressure and impact analyses were to determine if the induced stresses at the score patterns in the cylindrical body of the container were sufficient to induce failure. Analytical responses of the container to the imposed loads were obtained with finite element analysis methodology. The computer codes ABAQUS and VEC/DYNA3D were used to obtain the results. Results of the pressure analysis indicate that failure of the container body would be expected to occur at the score pattern for a static internal pressure of 500 psi. Also, results from three impact orientations for a 7-ft drop indicate that membrane stresses in the vicinity of the score pattern are above critical crack growth stress magnitudes, especially at low ([minus]60[degrees]F) temperatures.

  16. Dynamic impact and pressure analysis of the insensitive munitions container PA103 with modified design features

    SciTech Connect

    Handy, K.D.

    1993-06-01

    This report presents analytical analyses of the insensitive munitions container PA103, with modified design features for a static internal pressure of 500 psi and for a dynamic impact resulting from a 7-ft free fall onto a rigid surface. The modified design features addressed by the analyses were the inclusion of a score pattern on the container cylindrical body and a plastic plate (fuse) sandwiched between metal flanges on the container end. The objectives of both the pressure and impact analyses were to determine if the induced stresses at the score patterns in the cylindrical body of the container were sufficient to induce failure. Analytical responses of the container to the imposed loads were obtained with finite element analysis methodology. The computer codes ABAQUS and VEC/DYNA3D were used to obtain the results. Results of the pressure analysis indicate that failure of the container body would be expected to occur at the score pattern for a static internal pressure of 500 psi. Also, results from three impact orientations for a 7-ft drop indicate that membrane stresses in the vicinity of the score pattern are above critical crack growth stress magnitudes, especially at low ({minus}60{degrees}F) temperatures.

  17. Preliminary design features of the RASCAL: A NASA /Army rotorcraft in-flight simulator

    NASA Technical Reports Server (NTRS)

    Aiken, Edwin W.; Jacobsen, Robert A.; Eshow, Michelle M.; Hindson, William S.; Doane, Douglas H.

    1993-01-01

    Salient design features of a new NASA/Army research rotorcraft - the Rotorcraft-Aircrew Systems Concepts Airborne Laboratory (RASCAL) - are described. Using a UH-60A Black Hawk helicopter as a baseline vehicle, the RASCAL will be a flying laboratory capable of supporting the research requirements of major NASA and Army guidance, control, and display research programs. The paper describes the research facility requirements of these programs together with other critical constraints on the design of the research system, including safety-of-flight. Research program schedules demand a phased development approach, wherein specific research capability milestones are met and flight research projects are flown throughout the complete development cycle of the RASCAL. This development approach is summarized, and selected features of the research system are described. The research system includes a full-authority, programmable, fault-tolerant/fail-safe, fly-by-wire flight control system and a real-time obstacle detection and avoidance system which will generate low-altitude guidance commands to the pilot on a wide field-of-view, color helmet-mounted display.

  18. Impact of burner design features on sooting in residential oil fired systems

    SciTech Connect

    Butcher, T.; McNeill, F.; Celebi, Y.; Wegrzyn, J.

    1986-11-01

    This report describes the results of a study on soot production by residential oil burners with an emphasis on condensing system applications. The work has followed a related study at Brookhaven National Laboratory completed in June 1984. Work in the current project has been aimed at the effects of specific burner design features on soot. Soot production during burner startup and shutdown has been shown to be significant for heat exchanger fouling in some systems. A new method has been developed for measuring transient smoke involving a multipass light extinction technique. A general review of soot measurement techniques and the details of the system used in the experimental work are included. Specific burner design features evaluated include high static discharge pressure fans, high startup excess air, nozzle and fuel line heating, burner heat pressure drop, and fuel flow control. Both high pressure fans and high startup excess air were found to significantly improve startup behavior. This result is consistent with simple flow models in which a furnace or boiler system is related to a cavity resonator. Measurements showed that nozzle heating can significantly improve spray droplet size distribution. Tests in both condensing and non-condensing systems indicated that a commercial nozzle heater reduces smoke over the first two minutes of operation. The effect was most significant at low excess air.

  19. Diffusive Barrier and Getter Under Waste Packages VA Reference Design Feature Evaluations

    SciTech Connect

    MacNeil, K.

    1999-05-24

    This technical document evaluates those aspects of the diffusive barrier and getter features which have the potential for enhancing the performance of the Viability Assessment Reference Design and are also directly related to the key attributes for the repository safety strategy of that design. The effects of advection, hydrodynamic dispersion, and diffusion on the radionuclide migration rates through the diffusive barrier were determined through the application of the one-dimensional, advection/dispersion/diffusion equation. The results showed that because advective flow described by the advection-dispersion equation dominates, the diffusive barrier feature alone would not be effective in retarding migration of radiocuclides. However, if the diffusive barrier were combined with one or more features that reduced the potential for advection, then transport of radionuclides would be dominated by diffusion and their migration from the EBS would be impeded. Apatite was chosen as the getter material used for this report. Two getter configurations were developed, Case 1 and Case 2. As in the evaluation of the diffusive barrier, the effects of advection, hydrodynamic dispersion, and diffusion on the migration of radionuclides through the getter are evaluated. However, in addition to these mechanisms, the one-dimensional advection/dispersion/diffusion model is modified to include the effect of sorption on radionuclide migration rates through the sorptive medium (getter). As a result of sorption, the longitudinal dispersion coefficient, and the average linear velocity are effectively reduced by the retardation factor. The retardation factor is a function of the getter material's dry bulk density, sorption coefficient and moisture content. The results of the evaluation showed that a significant delay in breakthrough through the getter can be achieved if the thickness of the getter barrier is increased.

  20. [Design and Preparation of Plant Bionic Materials Based on Optical and Infrared Features Simulation].

    PubMed

    Jiang, Xiao-jun; Lu, Xu-liang; Pan, Jia-liang; Zhang, Shuan-qin

    2015-07-01

    Due to the life characteristics such as physiological structure and transpiration, plants have unique optical and infrared features. In the optical band, because of the common effects of chlorophyll and water, plant leafs show spectral reflectance characteristics change in 550, 680, 1400 and 1900 nm significantly. In the infrared wave band, driven by transpiration, plants could regulate temperature on their own initiative, which make the infrared characteristics of plants different from artificial materials. So palnt bionic materials were proposed to simulate optical and infrared characteristics of plants. By analyzing formation mechanism of optical and infrared features about green plants, the component design and heat-transfer process of plants bionic materials were studied, above these the heat-transfer control formulation was established. Based on water adsorption/release compound, optical pigments and other man-made materials, plant bionic materials preparation methods were designed which could simulate the optical and infrared features of green plants. By chemical casting methods plant bionic material films were prepared, which use polyvinyl alcohol as film forming and water adsorption/release compound, and use optical pigments like chrome green and macromolecule yellow as colouring materials. The research conclusions achieved by testings figured out: water adsorption/release testing showed that the plant bionic materials with a certain thickness could absorb 1.3 kg water per square meter, which could satisfy the water usage of transpiration simulation one day; the optical and infrared simulated effect tests indicated that the plant bionic materials could preferably simulate the spectral reflective performance of green plants in optical wave band (380-2500 nm, expecially in 1400 and 1900 nm which were water absorption wave band of plants), and also it had similar daily infrared radiation variations with green plants, daily average radiation temperature

  1. Design and novel type of a magnetorheological damper featuring piston bypass hole

    NASA Astrophysics Data System (ADS)

    Sohn, Jung Woo; Oh, Jong-Seok; Choi, Seung-Bok

    2015-03-01

    This work proposes a novel type of magnetorheological (MR) damper configuration from which an excellent ride comfort can be achieved without using a sophisticated controller scheme. The proposed novel MR damper is featured by piston bypass holes to achieve low slope of the damping force in the pre-yield (low-piston-velocity) region and high magnitude of the damping force in the post-yield (high-piston-velocity) region. A mathematical model for the damping force of the proposed MR damper is formulated followed by the investigation on damping characteristics with respect to several geometrical design parameters such as the number of piston bypass hole, the diameter of the hole, the gap size of the orifice, the orifice length, the diameter of the bobbin, and the height of the coil. After selecting the main design parameters from the simulation results, numerical simulations for the damping force characteristics are conducted with eight design parameter sets to evaluate the significant effect on the damping force performance. The proposed MR dampers are then manufactured with the same design parameter sets and the damping force characteristics are experimentally obtained and compared with the analytical simulation results. It is identified from the parametric investigations that the size and the number of the piston bypass hole are very important on damping force characteristics of the proposed MR damper.

  2. Environmental Designs for Reading from Imaging Workstations: Ergonomic and Architectural Features

    NASA Astrophysics Data System (ADS)

    Horii, Steven C.; Horii, Howard N.; Mun, Seong K.; Benson, Harold R.; Zeman, Robert K.

    1989-05-01

    Despite the rapid progress made in the electronic design of imaging workstations for medicine, much less effort has gone into the design of environments in which such systems will be used. Based on studies of radiologist film reading sessions, considerable time will be spent working at such viewing systems. If the rooms in which the workstations are placed are not conducive to comfortable work, it will certainly not favor electronic viewing over film reading. In examining existing reading environments, it is also apparent that they are not optimum, even for film. Since some of the problems for film and electronic viewing overlap, such as heat generation (by the alternators, viewboxes, or workstation electronics) and glare from light sources, it should be possible to develop solutions which are applicable to both environments or to rooms which will feature both viewing systems. This paper will discuss some of the approaches to designing environments in which viewing of images is supported by the room architecture and engineering and not degraded by it. To illustrate these points, a design based on the constraint of a real room size and available architectural materials will be developed.

  3. Multivariate Statistical Analysis of Cigarette Design Feature Influence on ISO TNCO Yields.

    PubMed

    Agnew-Heard, Kimberly A; Lancaster, Vicki A; Bravo, Roberto; Watson, Clifford; Walters, Matthew J; Holman, Matthew R

    2016-06-20

    The aim of this study is to explore how differences in cigarette physical design parameters influence tar, nicotine, and carbon monoxide (TNCO) yields in mainstream smoke (MSS) using the International Organization of Standardization (ISO) smoking regimen. Standardized smoking methods were used to evaluate 50 U.S. domestic brand cigarettes and a reference cigarette representing a range of TNCO yields in MSS collected from linear smoking machines using a nonintense smoking regimen. Multivariate statistical methods were used to form clusters of cigarettes based on their ISO TNCO yields and then to explore the relationship between the ISO generated TNCO yields and the nine cigarette physical design parameters between and within each cluster simultaneously. The ISO generated TNCO yields in MSS are 1.1-17.0 mg tar/cigarette, 0.1-2.2 mg nicotine/cigarette, and 1.6-17.3 mg CO/cigarette. Cluster analysis divided the 51 cigarettes into five discrete clusters based on their ISO TNCO yields. No one physical parameter dominated across all clusters. Predicting ISO machine generated TNCO yields based on these nine physical design parameters is complex due to the correlation among and between the nine physical design parameters and TNCO yields. From these analyses, it is estimated that approximately 20% of the variability in the ISO generated TNCO yields comes from other parameters (e.g., filter material, filter type, inclusion of expanded or reconstituted tobacco, and tobacco blend composition, along with differences in tobacco leaf origin and stalk positions and added ingredients). A future article will examine the influence of these physical design parameters on TNCO yields under a Canadian Intense (CI) smoking regimen. Together, these papers will provide a more robust picture of the design features that contribute to TNCO exposure across the range of real world smoking patterns. PMID:27222918

  4. Noble metals-compatible melter features development Phase 1: Establishing functional and design criteria and design concepts

    SciTech Connect

    Elmore, M.R.; Siemens, D.H.; Chapman, C.C.

    1996-03-01

    Premature failures have occurred in melters at Japan`s Tokai Mockup Facility and at the Federal Republic of Germany (FRG) PAMELA plant during processing of feeds with high levels of noble metals. Melter failure was due to the accumulation of an electrically conductive, noble metals-containing precipitates in the glass, that then resulted in short circuiting of the electrodes. A comparison was made of the anticipated Hanford Waste Vitrification Plant (HWVP) feed with the feeds processed in the FRG and Japanese melters. The evaluation showed that comparable levels of noble metals and other potential precipitate-forming components (e.g. Cr/Fe/Ni-spinels) exist in the HWVP feed. As a result, the HWVP project made a decision to modify the present reference melter design to include features to prevent the precipitation and accumulation or otherwise accommodate precipitated phases on a routine basis without loss of production capacity.

  5. Biomaterial design for specific cellular interactions: Role of surface functionalization and geometric features

    NASA Astrophysics Data System (ADS)

    Kolhar, Poornima

    The areas of drug delivery and tissue engineering have experienced extraordinary growth in recent years with the application of engineering principles and their potential to support and improve the field of medicine. The tremendous progress in nanotechnology and biotechnology has lead to this explosion of research and development in biomedical applications. Biomaterials can now be engineered at a nanoscale and their specific interactions with the biological tissues can be modulated. Various design parameters are being established and researched for design of drug-delivery carriers and scaffolds to be implanted into humans. Nanoparticles made from versatile biomaterial can deliver both small-molecule drugs and various classes of bio-macromolecules, such as proteins and oligonucleotides. Similarly in the field of tissue engineering, current approaches emphasize nanoscale control of cell behavior by mimicking the natural extracellular matrix (ECM) unlike, traditional scaffolds. Drug delivery and tissue engineering are closely connected fields and both of these applications require materials with exceptional physical, chemical, biological, and biomechanical properties to provide superior therapy. In the current study the surface functionalization and the geometric features of the biomaterials has been explored. In particular, a synthetic surface for culture of human embryonic stem cells has been developed, demonstrating the importance of surface functionalization in maintaining the pluripotency of hESCs. In the second study, the geometric features of the drug delivery carriers are investigated and the polymeric nanoneedles mediated cellular permeabilization and direct cytoplasmic delivery is reported. In the third study, the combined effect of surface functionalization and geometric modification of carriers for vascular targeting is enunciated. These studies illustrate how the biomaterials can be designed to achieve various cellular behaviors and control the

  6. Three-Dimensional Elastomeric Scaffolds Designed with Cardiac-Mimetic Structural and Mechanical Features

    PubMed Central

    Neal, Rebekah A.; Jean, Aurélie; Park, Hyoungshin; Wu, Patrick B.; Hsiao, James; Engelmayr, George C.; Langer, Robert

    2013-01-01

    Tissue-engineered constructs, at the interface of material science, biology, engineering, and medicine, have the capacity to improve outcomes for cardiac patients by providing living cells and degradable biomaterials that can regenerate the native myocardium. With an ultimate goal of both delivering cells and providing mechanical support to the healing heart, we designed three-dimensional (3D) elastomeric scaffolds with (1) stiffnesses and anisotropy mimicking explanted myocardial specimens as predicted by finite-element (FE) modeling, (2) systematically varied combinations of rectangular pore pattern, pore aspect ratio, and strut width, and (3) structural features approaching tissue scale. Based on predicted mechanical properties, three scaffold designs were selected from eight candidates for fabrication from poly(glycerol sebacate) by micromolding from silicon wafers. Large 20×20 mm scaffolds with high aspect ratio features (5:1 strut height:strut width) were reproducibly cast, cured, and demolded at a relatively high throughput. Empirically measured mechanical properties demonstrated that scaffolds were cardiac mimetic and validated FE model predictions. Two-layered scaffolds providing fully interconnected pore networks were fabricated by layer-by-layer assembly. C2C12 myoblasts cultured on one-layered scaffolds exhibited specific patterns of cell elongation and interconnectivity that appeared to be guided by the scaffold pore pattern. Neonatal rat heart cells cultured on two-layered scaffolds for 1 week were contractile, both spontaneously and in response to electrical stimulation, and expressed sarcomeric α-actinin, a cardiac biomarker. This work not only demonstrated several scaffold designs that promoted functional assembly of rat heart cells, but also provided the foundation for further computational and empirical investigations of 3D elastomeric scaffolds for cardiac tissue engineering. PMID:23190320

  7. Hydraulic processes on alluvial fans

    SciTech Connect

    French, R.H.

    1987-01-01

    Alluvial fans are among the most prominent landscape features in the American Southwest and throughout the semi-arid and arid regions of the world. The importance of developing a qualitative and quantitative understanding of the hydraulic processes which formed, and which continue to modify, these features derives from their rapid and significant development over the past four decades. As unplanned urban sprawl moved from valley floors onto alluvial fans, the serious damage incurred from infrequent flow events has dramatically increased. This book presents a discussion of our current and rapidly expanding knowledge of hydraulic processes on alluvial fans. It addresses the subject from a multidisciplinary viewpoint, acquainting the reader with geological principles pertinent to the analysis of hydraulic processes on alluvial fans.

  8. Hydraulic fracturing-1

    SciTech Connect

    Not Available

    1990-01-01

    This book contains papers on hydraulic fracturing. Topics covered include: An overview of recent advances in hydraulic fracturing technology; Containment of massive hydraulic fracture; and Fracturing with a high-strength proppant.

  9. Extraction of Airport Features from High Resolution Satellite Imagery for Design and Risk Assessment

    NASA Technical Reports Server (NTRS)

    Robinson, Chris; Qiu, You-Liang; Jensen, John R.; Schill, Steven R.; Floyd, Mike

    2001-01-01

    The LPA Group, consisting of 17 offices located throughout the eastern and central United States is an architectural, engineering and planning firm specializing in the development of Airports, Roads and Bridges. The primary focus of this ARC project is concerned with assisting their aviation specialists who work in the areas of Airport Planning, Airfield Design, Landside Design, Terminal Building Planning and design, and various other construction services. The LPA Group wanted to test the utility of high-resolution commercial satellite imagery for the purpose of extracting airport elevation features in the glide path areas surrounding the Columbia Metropolitan Airport. By incorporating remote sensing techniques into their airport planning process, LPA wanted to investigate whether or not it is possible to save time and money while achieving the equivalent accuracy as traditional planning methods. The Affiliate Research Center (ARC) at the University of South Carolina investigated the use of remotely sensed imagery for the extraction of feature elevations in the glide path zone. A stereo pair of IKONOS panchromatic satellite images, which has a spatial resolution of 1 x 1 m, was used to determine elevations of aviation obstructions such as buildings, trees, towers and fence-lines. A validation dataset was provided by the LPA Group to assess the accuracy of the measurements derived from the IKONOS imagery. The initial goal of this project was to test the utility of IKONOS imagery in feature extraction using ERDAS Stereo Analyst. This goal was never achieved due to problems with ERDAS software support of the IKONOS sensor model and the unavailability of imperative sensor model information from Space Imaging. The obstacles encountered in this project pertaining to ERDAS Stereo Analyst and IKONOS imagery will be reviewed in more detail later in this report. As a result of the technical difficulties with Stereo Analyst, ERDAS OrthoBASE was used to derive aviation

  10. Assessment of hydraulic performance and biocompatibility of a MagLev centrifugal pump system designed for pediatric cardiac or cardiopulmonary support.

    PubMed

    Dasse, Kurt A; Gellman, Barry; Kameneva, Marina V; Woolley, Joshua R; Johnson, Carl A; Gempp, Thomas; Marks, John D; Kent, Stella; Koert, Andrew; Richardson, J Scott; Franklin, Steve; Snyder, Trevor A; Wearden, Peter; Wagner, William R; Gilbert, Richard J; Borovetz, Harvey S

    2007-01-01

    The treatment of children with life-threatening cardiac and cardiopulmonary failure is a large and underappreciated public health concern. We have previously shown that the CentriMag is a magnetically levitated centrifugal pump system, having the utility for treating adults and large children (1,500 utilized worldwide). We present here the PediVAS, a pump system whose design was modified from the CentriMag to meet the physiological requirements of young pediatric and neonatal patients. The PediVAS is comprised of a single-use centrifugal blood pump, reusable motor, and console, and is suitable for right ventricular assist device (RVAD), left ventricular assist device (LVAD), biventricular assist device (BVAD), or extracorporeal membrane oxygenator (ECMO) applications. It is designed to operate without bearings, seals and valves, and without regions of blood stasis, friction, or wear. The PediVAS pump is compatible with the CentriMag hardware, although the priming volume was reduced from 31 to 14 ml, and the port size reduced from 3/8 to (1/4) in. For the expected range of pediatric flow (0.3-3.0 L/min), the PediVAS exhibited superior hydraulic efficiency compared with the CentriMag. The PediVAS was evaluated in 14 pediatric animals for up to 30 days, demonstrating acceptable hydraulic function and hemocompatibility. The current results substantiate the performance and biocompatibility of the PediVAS cardiac assist system and are likely to support initiation of a US clinical trial in the future. PMID:18043164

  11. Assessment of Hydraulic Performance and Biocompatibility of a MagLev Centrifugal Pump System Designed for Pediatric Cardiac or Cardiopulmonary Support

    PubMed Central

    Dasse, Kurt A.; Gellman, Barry; Kameneva, Marina V.; Woolley, Joshua R.; Johnson, Carl A.; Gempp, Thomas; Marks, John D.; Kent, Stella; Koert, Andrew; Richardson, J. Scott; Franklin, Steve; Snyder, Trevor A.; Wearden, Peter; Wagner, William R.; Gilbert, Richard J.; Borovetz, Harvey S.

    2011-01-01

    The treatment of children with life-threatening cardiac and cardiopulmonary failure is a large and underappreciated public health concern. We have previously shown that the CentriMag is a magnetically levitated centrifugal pump system, having the utility for treating adults and large children (1,500 utilized worldwide). We present here the Pedi-VAS, a pump system whose design was modified from the CentriMag to meet the physiological requirements of young pediatric and neonatal patients. The PediVAS is comprised of a single-use centrifugal blood pump, reusable motor, and console, and is suitable for right ventricular assist device (RVAD), left ventricular assist device (LVAD), biventricular assist device (BVAD), or extracorporeal membrane oxygenator (ECMO) applications. It is designed to operate without bearings, seals and valves, and without regions of blood stasis, friction, or wear. The PediVAS pump is compatible with the CentriMag hardware, although the priming volume was reduced from 31 to 14 ml, and the port size reduced from 3/8 to ¼ in. For the expected range of pediatric flow (0.3–3.0 L/min), the PediVAS exhibited superior hydraulic efficiency compared with the CentriMag. The PediVAS was evaluated in 14 pediatric animals for up to 30 days, demonstrating acceptable hydraulic function and hemocompatibility. The current results substantiate the performance and biocompatibility of the PediVAS cardiac assist system and are likely to support initiation of a US clinical trial in the future. PMID:18043164

  12. Toward the commoditization of translational genomic research: Design and implementation features of the Galaxy genomic workbench.

    PubMed Central

    Lazarus, Ross; Taylor, James; Qiu, Weiliang; Nekrutenko, Anton

    2008-01-01

    Although there is now plenty of genomic data and no shortage of analysis methods for translational genomic research, many biologists do not have efficient and transparent access to the computational resources they need. No single data resource or analysis application is ever likely to efficiently address all aspects of any individual researcher’s needs, so most researchers are forced to manually integrate data and outputs from multiple resources. The inevitable heterogeneity of data formats and of command syntax between data resources and software applications presents a major obstacle, particularly to those biologists lacking practical informatics skills. We describe some design and implementation features of an open-source application that supports the integration of the best available third-party genomics software applications, data and annotation resources into a coherent framework, substantially overcoming many practical challenges associated with actually doing translational genomic research. PMID:21347127

  13. Effectiveness of training in organizations: a meta-analysis of design and evaluation features.

    PubMed

    Arthur, Winfred; Bennett, Winston; Edens, Pamela S; Bell, Suzanne T

    2003-04-01

    The authors used meta-analytic procedures to examine the relationship between specified training design and evaluation features and the effectiveness of training in organizations. Results of the meta-analysis revealed training effectiveness sample-weighted mean ds of 0.60 (k = 15, N = 936) for reaction criteria, 0.63 (k = 234, N = 15,014) for learning criteria, 0.62 (k = 122, N = 15,627) for behavioral criteria, and 0.62 (k = 26, N = 1,748) for results criteria. These results suggest a medium to large effect size for organizational training. In addition, the training method used, the skill or task characteristic trained, and the choice of evaluation criteria were related to the effectiveness of training programs. Limitations of the study along with suggestions for future research are discussed. PMID:12731707

  14. Design features of on-line anatomy information resources: a comparison with the Digital Anatomist.

    PubMed Central

    Kim, S.; Brinkley, J. F.; Rosse, C.

    1999-01-01

    In order to update the design of the next generation of the Digital Anatomist, we have surveyed teaching assistants who have used the Digital Anatomist for learning and teaching anatomy as medical students, and have also examined available anatomy web sites with sufficient content to support learning. The majority of web sites function in an atlas mode and provide for the identification of structures. These atlases incorporate a variety of features for interactivity with 2D images, some of which are not available in the Digital Anatomist. The surveys suggest that the greatest need is for on-line access to comprehensive and detailed anatomical information and for the development of knowledge-based methods that allow the direct manipulation of segmented 3D graphical models by the user. The requirement for such interactivity is a comprehensive symbolic model of the physical organization of the body that can support inference. Images Fig 1 PMID:10566421

  15. Simulation Analysis of Certain Hydraulic Lifting Appliance under Different Working Conditions

    NASA Astrophysics Data System (ADS)

    Lei, Huang; Genfu, Yuan; Xuehui, Chen

    Being typical of mechanical and electronic hydraulics appliance, hydraulic lifting appliance has many working conditions due to its particularities. Properties of hydraulic system decide high efficiency, security as well as stability under different working conditions. Beginning with simulation analysis on hydraulic system of hydraulic lifting appliance under different working conditions, the essay analyzes a certain hydraulic system through which design references can be offered for optimizing hydraulic system properties via hydraulic system force and changes of torque. And then properties of hydraulic system can be improved and a hydraulic system with stable performance can be obtained.

  16. Hydraulic hammer drilling technology: Developments and capabilities

    SciTech Connect

    Melamed, Y.; Kiselev, A.; Gelfgat, M.; Dreesen, D.; Blacic, J.

    1996-12-31

    Percussion drilling technology was considered many years ago as one of the best approaches for hard rock drilling. Unfortunately the efficiency of most hydraulic hammer (HH) designs was very low (8% maximum), so they were successfully used in shallow boreholes only. Thirty years of research and field drilling experience with HH application in Former Soviet Union (FSU) countries led to the development of a new generation of HH designs with a proven efficiency of 40%. That advance achieved good operational results in hard rock at depths up to 2,000 m and more. The most recent research has shown that there are opportunities to increase HH efficiency up to 70%. This paper presents HH basic design principles and operational features. The advantages of HH technology for coiled-tubing drilling is shown on the basis of test results recently conducted in the US.

  17. Comparing Infants' Use of Featural and Spatiotemporal Information in an Object Individuation Task Using a New Event-Monitoring Design

    ERIC Educational Resources Information Center

    Krojgaard, Peter

    2007-01-01

    Discussions have recently taken place on whether spatiotemporal information is more important than featural information when infants attempt to individuate objects. Hitherto, spatiotemporal and featural information have only been compared directly by using cognitively demanding "event-mapping" designs" (e.g. Xu & Carey, 1996 ), whereas the simpler…

  18. Cigarette Design Features in Low-, Middle-, and High-Income Countries

    PubMed Central

    Caruso, Rosalie V.; O'Connor, Richard J.

    2012-01-01

    Previous studies have shown that country income grouping is correlated with cigarette engineering. Cigarettes (N = 111 brands) were purchased during 2008–2010 from 11 low-, middle-, and high-income countries to assess physical dimensions and an array of cigarette design features. Mean ventilation varied significantly across low- (7.5%), middle- (15.3%), and high-income (26.2%) countries (P ≤ 0.001). Differences across income groups were also seen in cigarette length (P = 0.001), length of the tipping paper (P = 0.01), filter weight (P = 0.017), number of vent rows (P = 0.003), per-cigarette tobacco weight (P = 0.04), and paper porosity (P = 0.008). Stepwise linear regression showed ventilation and tobacco length as major predictors of ISO tar yields in low-income countries (P = 0.909, 0.047), while tipping paper (P < 0.001), filter length (P < 0.001), number of vent rows (P = 0.014), and per-cigarette weight (P = 0.015) were predictors of tar yields in middle-income countries. Ventilation (P < 0.001), number of vent rows (P = 0.009), per-cigarette weight (P < 0.001), and filter diameter (P = 0.004) predicted tar yields in high-income countries. Health officials must be cognizant of cigarette design issues to provide effective regulation of tobacco products. PMID:22645621

  19. PRESTO, the on-line photon energy spectrometer at FERMI: design, features and commissioning results.

    PubMed

    Svetina, Cristian; Cocco, Daniele; Mahne, Nicola; Raimondi, Lorenzo; Ferrari, Eugenio; Zangrando, Marco

    2016-01-01

    Measurement of the emission wavelength and the spectral content of the photon radiation is essential information for both machine and experimental physicists at a free-electron laser (FEL) user facility. Knowledge of the photon beam spectral properties is needed during the machine optimization and for performing machine studies (i.e. monitoring the change of the FEL output as a function of the machine parameters). The experimentalists, on the other hand, need to know the photon beam spectral distribution of the source, shot to shot, to discriminate the acquired data. Consequently, the main requirement for the instrument, supposed to obtain this information, is the capability of working on-line and shot-to-shot, with minimal perturbation of the beam delivered to the experimental stations. Starting from the grating fundamental equations, the conceptual design of the FERMI Pulse-Resolved Energy Spectrometer: Transparent and On-line (PRESTO) is presented, explaining the optical design in detail. The performance of PRESTO, in terms of resolving power, efficiency and spectral response, is also discussed. Finally, some useful features beyond the usual measurement of the energy spectrum are reported, as they have been routinely used by both machine and experimental physicists. PMID:26698043

  20. Design and Operating Features of the ITER 4.5 K Cryoplant

    SciTech Connect

    Kalinine, V.; Haange, R.; Shatil, N.; Millet, F.; Jager, B.; Briend, P.; Crispel, S.; Dauguet, P.

    2004-06-23

    The main cryogenic users of ITER are the superconducting magnet system and the cryogenic vacuum pumps. The magnet system consists of 18 toroidal field and six poloidal field coils and the central solenoid coils. The cryogenic vacuum pumps contain eight pumps for the vacuum vessel, up to four pumps for the neutral beam injectors and two for the tokamak cryostat.The paper presents the current design status of the ITER cryoplant and its operating features that allow stable and flexible operation for different plasma pulsing scenarios and transient operating modes including cool-down and coil quench. The LHe plant operates in a combined liquefaction / refrigeration mode. Liquefied helium is used for the coil current leads and for cool-down of the cryopumps after their regeneration at 80 K. The operating temperature of the LHe plant can vary in the range of 4.3 K to 4.5 K to satisfy different cooling demands of various plasma scenarios. The LHe plant is designed for a large variation ratio of refrigeration to liquefaction in order to facilitate filling of the coils with a large amount of supercritical helium after a standard cool-down or specific cool-down mode following a fast energy discharge.

  1. NGNP Point Design - Results of the Initial Neutronics and Thermal-Hydraulic Assessments During FY-03, Rev. 1

    SciTech Connect

    Philip E. MacDonald; James W. Sterbentz; Robert L. Sant; P. Bayless; H. D. Gougar; R. L. Moore; A. M. Ougouag; W. K. Terry

    2003-09-01

    This report presents the preliminary preconceptual designs for two possible versions of the Next Generation Nuclear Plant (NGNP), one for a prismatic fuel type helium gas-cooled reactor and one for a pebble bed fuel helium gas reactor. Both designs are to meet three basic requirements: a coolant outlet temperature of 1000 °C, passive safety, and a total power output consistent with that expected for commercial high-temperature gas-cooled reactors. The two efforts are discussed separately below. The analytical results presented in this report are very promising, however, we wish to caution the reader that future, more detailed, design work will be needed to provide final answers to a number of key questions including the allowable power level, the inlet temperature, the power density, the optimum fuel form, and others. The point design work presented in this report provides a starting point for other evaluations, and directions for the detailed design, but not final answers.

  2. Scale-dependency of the hydraulic properties of a variably saturated heterogeneous sandy subsoil

    NASA Astrophysics Data System (ADS)

    Javaux, M.; Vanclooster, M.

    2006-08-01

    SummaryThe effective hydraulic behaviour of heterogeneous sand was experimentally investigated at two scales under transient flow upper boundary conditions. At the monoliths-scale, one-dimensional inverse modelling was performed from a transient infiltration experiment by implementing in the objective function the outflow and pressure head time series at four depths. Notwithstanding the important heterogeneity of the subsoil, principally due to the presence of discontinuous clay and a stone layer, we observed that the effective behaviour was surprisingly well reproduced. It was also observed that the structural features mainly induced a kind of hysteresis between the saturation and drainage cycles of the outflow time series. Subsequently, 104 Kopecky cores (100 cm 3) were sub-sampled throughout the monolith, mainly in the sandy matrix. The variability of local hydraulic parameters was investigated by optimising the local hydraulic parameters from multi-step outflow experiments and measured retention points. The comparison between 1-D optimised, measured and Kopecky-averaged retention curves showed relatively similar shape near saturation. In contrast to this, important discrepancies existed between averaged local scale hydraulic conductivity and effective hydraulic conductivity close to saturation. Different experimental designs at different scales may explain the observed discrepancies. It is further suggested that the monolith-scale effective hydraulic functions are more representative for wet soil conditions. This case study illustrates the complexity of finding validated scaling relationships for the hydraulic properties of heterogeneous soils at scales larger than the usual small column scale.

  3. Composite hydraulic system

    SciTech Connect

    Williamson, W.A.

    1987-03-17

    A composite hydraulic system is described for a work vehicle having an implement hydraulic circuit and a steering hydraulic circuit comprising a first pump which supplies the implement hydraulic circuit primarily, a second pump which supplies the steering hydraulic circuit primarily, a third pump which is operable also as a motor and which transfers hydraulic fluid between the implement and the steering hydraulic circuits, an engine which operates the three pumps simultaneously, and servo system means whereby the third pump under at least one condition of operation operates as a motor to provide regeneration.

  4. Electric versus hydraulics versus pneumatics

    SciTech Connect

    Not Available

    1985-01-01

    This book presents a collection of papers from a conference which considered the advantages and disadvantages of electric, hydraulic and pneumatic drives and actuators. The volume follows on the success of the 1983 conference on electric and hydraulic drives. Topics considered include fork lift trucks - an ideal application for regenerative transmissions; a hybrid-electric power system with hydrostatic transmission; electrics and hydraulics on roadheader machinery; hydraulic, electrical, pneumatic control - which way to go. an electrically-powered servo to drive the two axes of a missile launching platform - pros and cons when compared with the traditional hydraulic solution; the encapsulation of a novel intrinsically safe displacement transducer; mobile cryogenic pumping systems; automation of a wood-turning machine, hydraulic or electric. The choice of a servo motor for a specific application; developments in the design and control of pneumatic linear actuators; compressed air purification for instrumentation in the high technology industries; trends in prime mover choice for powered hand tools; and choosing the drive system for the right application.

  5. Evaluating the Operational Features of an Unconventional Dual-Bay U-Turn Design for Intersections

    PubMed Central

    Xiang, Yun; Li, Zhibin; Wang, Wei; Chen, Jingxu; Wang, Hao; Li, Ye

    2016-01-01

    Median U-turn intersection treatment (MUTIT) has been considered an alternative measure to reduce congestion and traffic conflict at intersection areas. The MUTIT is sometimes difficult to implement in the field because it requires wide median on arterials for U-turn vehicles. The objective of this study is to introduce an unconventional U-turn treatment (UUT) for intersections which requires less median space but is also effective. The UUT has a dual-bay design with different turning radiuses for small and large vehicles. The VISSIM simulation model was developed to evaluate the operational features of the UUT. The model was calibrated using data collected from intersections in China. The capacity, delay and number of stops were evaluated and compared with the direct-left-turn (DLT) for the same intersections. The results showed that the UUT significantly improved the operations at intersection areas, especially when volume/capacity ratio is small, and ratio of left-turn to through traffic is small. With the UUT, the capacity is increased by 9.81% to 10.38%, vehicle delay is decreased by 18.5% to 40.1%, and number of stops is decreased by 23.19% to 36.62%, when volume/capacity ratio is less than 0.50. The study also found that traffic efficiency could be further improved when the UUT is designed in conjunction with signal control. In the case, the UUT plus signalized control increases the capacity by 25% to 26.02%, decreases vehicle delay by 50.5% to 55.8%, and reduces number of stops by 69.5%, compared with the traditional DLT. PMID:27467127

  6. Evaluating the Operational Features of an Unconventional Dual-Bay U-Turn Design for Intersections.

    PubMed

    Xiang, Yun; Li, Zhibin; Wang, Wei; Chen, Jingxu; Wang, Hao; Li, Ye

    2016-01-01

    Median U-turn intersection treatment (MUTIT) has been considered an alternative measure to reduce congestion and traffic conflict at intersection areas. The MUTIT is sometimes difficult to implement in the field because it requires wide median on arterials for U-turn vehicles. The objective of this study is to introduce an unconventional U-turn treatment (UUT) for intersections which requires less median space but is also effective. The UUT has a dual-bay design with different turning radiuses for small and large vehicles. The VISSIM simulation model was developed to evaluate the operational features of the UUT. The model was calibrated using data collected from intersections in China. The capacity, delay and number of stops were evaluated and compared with the direct-left-turn (DLT) for the same intersections. The results showed that the UUT significantly improved the operations at intersection areas, especially when volume/capacity ratio is small, and ratio of left-turn to through traffic is small. With the UUT, the capacity is increased by 9.81% to 10.38%, vehicle delay is decreased by 18.5% to 40.1%, and number of stops is decreased by 23.19% to 36.62%, when volume/capacity ratio is less than 0.50. The study also found that traffic efficiency could be further improved when the UUT is designed in conjunction with signal control. In the case, the UUT plus signalized control increases the capacity by 25% to 26.02%, decreases vehicle delay by 50.5% to 55.8%, and reduces number of stops by 69.5%, compared with the traditional DLT. PMID:27467127

  7. Design features and performance of the LAMPF high-intensity beam area

    SciTech Connect

    Agnew, L.; Grisham, D.; Macek, R.J.; Sommer, W.F.; Werbeck, R.D.

    1983-01-01

    LAMPF is a multi-purpose high-intensity meson factory capable of producing a 1 mA beam of 800-MeV protons. The three target cells and the beam stop facilities in the high intensity area have many special design features that are required for operation in the presence of high heat loads and intense radiation fields where accessibility is extremely limited. Reliable targets, beam windows, beam stops, beam transport and diagnostic components, vacuum enclosures, and auxiliary systems have been developed. Sophisticated remote-handling systems are employed for maintenance. Complex protection systems have been developed to guard against damage caused by errant beam. Beam availability approaching 90% has been achieved at currents of 600 to 700 ..mu..A. A new facility for direct proton and neutron radiation effects studies will be installed in 1985. The new facility will provide an integrated spallation neutron flux of up to 5 x 10/sup 17/ m/sup -2/s/sup -1/ and will anable proton irradiation studies in the primary beam.

  8. Design and experiments of a novel magneto-rheological damper featuring bifold flow mode

    NASA Astrophysics Data System (ADS)

    Kim, Kyongsol; Chen, Zhaobo; Yu, Dong; Rim, Changhyon

    2016-07-01

    This study presents design and fabrication of a novel magneto-rheological (MR) damper with bifold flow mode gap to improve damping performance. The proposed MR damper is featured by inner flow mode gap connected to the outer flow mode gap through the feedback hole. A mathematical model of the damping force is established for the proposed MR damper and the magnetic circuit has been analyzed with the finite element method, which is used to validate the principle of the proposed MR damper. A conventional MR damper is fabricated with the same dimensions (radius, length) of the piston and is experimentally compared to confirm advantages of the proposed MR damper. The mechanical performance of the proposed MR damper is experimentally investigated and compared with the results by mathematical model and finite element analysis. The research results show that the controllable damping force and equivalent damping of the MR damper with bifold flow mode gap are much larger than those of the conventional MR damper.

  9. Thermal hydraulic features of the TMI accident

    NASA Astrophysics Data System (ADS)

    Tolman, B.

    1985-10-01

    The Three Mile island (TMI)-2 accident resulted in extensive core damage and recent data confirms that the reactor vessel was challenged from molten core materials. A hypothesized TMI accident scenario is presented that consistently explains the TMI data and is also consistent with research findings from independent severe fuel damage experiments. The TMI data will prove useful in confirming our understanding of severe core damage accidents under realistic reactor systems conditions. This understanding will aid in addressing safety and regulatory issues related to severe core damage accidents in light water reactors.

  10. UNIQUE FEATURES IN MAGNET DESIGNS FOR R AND D ENERGY RECOVERY LINAC AT BNL.

    SciTech Connect

    MENG,W.; JAIN, A.; GANETIS, G.; KAYRAN, D.; LITVINENKO, V.N.; LONGO, C.; MAHLER, G.; POZDEYEV, E.; TUOZZOLO, J.

    2007-06-25

    In this paper we describe the unique features and analysis techniques used on the magnets for a R&D Energy Recovery Linac (ERL) [1] under construction at the Collider Accelerator Department at BNL. The R&D ERL serves as a test-bed for future BNL ERLs, such as an electron-cooler-ERL at RHIC [2] and a future 20 GeV ERL electron-hadron at eRHIC [3]. Here we present select designs of various dipole and quadruple magnets which are used in Z-bend merging systems [4] and the returning loop, 3-D simulations of the fields in aforementioned magnets, particle tracking analysis, and the magnet's influence on beam parameters. We discuss an unconventional method of setting requirements on the quality of magnetic field and transferring them into measurable parameters as well as into manufacturing tolerances. We compare selected simulation with results of magnetic measurements. A 20 MeV R&D ERL (Fig. 1) is in an advanced phase of construction at the Collider-Accelerator Department at BNL, with commissioning planned for early 2009. In the R&D ERL, an electron beam is generated in a 2 MeV superconducting RF photo-gun, next is accelerated to 20 MeV in a 5 cell SRF linac, subsequently passed through a return loop, then decelerated to 2 MeV in the SRF linac, and finally is sent to a beam dump. The lattice of the R&D ERL is designed with a large degree of flexibility to enable the covering of a vast operational parameter space: from non-achromatic lattices to achromatic with positive, zero and negative R56 parameter. It also allows for large range tunability of Rlz and lattice RS4 parameters (which are important for transverse beam-break-up instability). Further details of the R&D ERL can be found elsewhere in these proceedings [5]. The return loop magnets are of traditional design with the following exceptions: (a) The bending radius of the 60{sup o} dipole magnets is 20 cm, which is rather small. We use 15{sup o} edges on both sides of the dipoles to split very strong focusing evenly

  11. 14 CFR 25.1435 - Hydraulic systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Hydraulic systems. 25.1435 Section 25.1435 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1435 Hydraulic systems. (a) Element design. Each element of...

  12. A distributed hydrologic model for the estimation of the design flood and for the hydraulic safety of existing dams in Sardinia (Italy)

    NASA Astrophysics Data System (ADS)

    Cortis, Clorinda; Sarigu, Alessio; Montaldo, Nicola; Saba, Andrea

    2013-04-01

    The recent floods observed in 2004 and 2008 in Sardinia (Italy) showed a significant flood increase in magnitude and frequency and put the attention on the problem of the hydraulic safety of existing dams. Thirty dams built for both electric production and water supply for irrigation and civil uses during the 1920-1960 are present in Sardinia (Italy). The distributed hydrologic model is an event model (FEST) which assesses runoff through a simplified approach based on Soil Conservation Service equations and runoff propagation through the Muskingum-Cunge approach. The FEST needs the calibration of different parameters: 1) the critical support area that defines the minimum drainage area required to initiate a channel, 2) the ratio between cross-section width and flood flow depth for hillslope, 3) the hillslope values of the Gaulckler-Stickler roughness coefficient, and 4) the Curve Number obtained/extracted from the landscape characteristics of each basin. The data collection of numerous historical flood observations of the Sardinian basins allow for the first time to accurately calibrate an hydrologic model for the Sardinian basins, characterized by hortonian runoff mechanisms typically, steep hillslopes and thin soils. Areas of the catchments are between 4 and 3147 Km2 and the basins are characterized by an high variability of the landscape characteristics such as geology, topography, soil, land use and vegetation. Using the calibrated hydrologic model and the synthetic design hyetograph the design floods of the dams are estimated. The comparison between peak flows of the generated design floods and those estimated using typical regionalized statistical methods (based for Sardinian studies on two components extreme value (TCEV) and logarithmic probabilistic distributions) shows contradiction and interesting results. For large scale basin (> 200 km2) the two contrasting methods agree, while for small basins the proposed method underestimates the peak respect to the

  13. Introduction to Hydraulics. Student's Manual.

    ERIC Educational Resources Information Center

    Texas Univ., Austin. Extension Instruction and Materials Center.

    This manual on hydraulics is one of a series of individualized instructional materials for students. The manual is self-paced, but is designed to be used under the supervision of an instructor. The manual contains 10 assignments, each with all the information needed, a list of objectives that should be met, and exercise questions that can help in…

  14. Artifactual kinds and functional design features: what a primate understands without language.

    PubMed

    Hauser, M D

    1997-09-01

    Of several domains of knowledge, humans appear to be born with an innately structured representational system for making sense of objects, what properties individuate them, how they move in space, and what causes them to move from one location to another. They also appear to make simple conceptual cuts between artifactual kinds and living kinds. The basis for this distinction seems to be a combination of crucial functional properties, together with a teleological (i.e., historical/intentional) stance, one that asks 'What was this object designed for?'. Although non-human primates also appear to have considerable understanding of objects, and often use objects as tools, it is not clear whether they draw a distinction between artifactual and living kinds, and if so, what factors guide this distinction. As a step in addressing this problem, I present experiments on a small New World monkey, the cotton-top tamarin (Saguinus oedipus oedipus), designed to reveal their understanding of the functional properties of tools using a procedure associated with minimal training. Specifically, the experiments explored whether tamarins distinguish between relevant and irrelevant properties of a tool, and further, understand that some features can be transformed with little cost to functionality. The first experiment was a means-end task and involved using a cane-like object (a tool) to access a piece of food. In this experiment, there were always two choices: either the food was immediately accessible because it was located on the inside of the cane's hook or less readily accessible because it was located on the outside of the hook. Most of the tamarins reached criterion on this task within a few sessions, consistently picking the cane with the most accessible food. Subsequent experiments (2-4) involved property changes (i.e., its color, texture, size and shape) that had either significant or relatively insignificant effects on the tool's function. In general, the tamarins appeared

  15. High temperature hydraulic seals

    NASA Astrophysics Data System (ADS)

    Williams, K. R.

    1993-05-01

    This program investigated and evaluated high temperature hydraulic sealing technology, including seals, fluids, and actuator materials. Test limits for fluid pressure and temperature were 8000 psi and 700 F respectively. The original plan to investigate CTFE fluid at 350 F as well as other fluids at higher temperatures was reduced in scope to include only the higher temperature investigation. Seals were obtained from 11 manufacturers. Design requirements including materials, dimensions, clearances, and tolerances were established and test modules were constructed from the detail designs which were produced. Nine piston seals and one rod seal were tested at temperatures ranging from -65 to +600 F and pressures to 6000 psi. Fluid performance under these conditions was evaluated. Details of this activity and results of the effort are summarized in this report.

  16. Selective perceptions of hydraulic fracturing.

    PubMed

    Sarge, Melanie A; VanDyke, Matthew S; King, Andy J; White, Shawna R

    2015-01-01

    Hydraulic fracturing (HF) is a focal topic in discussions about domestic energy production, yet the American public is largely unfamiliar and undecided about the practice. This study sheds light on how individuals may come to understand hydraulic fracturing as this unconventional production technology becomes more prominent in the United States. For the study, a thorough search of HF photographs was performed, and a systematic evaluation of 40 images using an online experimental design involving N = 250 participants was conducted. Key indicators of hydraulic fracturing support and beliefs were identified. Participants showed diversity in their support for the practice, with 47 percent expressing low support, 22 percent high support, and 31 percent undecided. Support for HF was positively associated with beliefs that hydraulic fracturing is primarily an economic issue and negatively associated with beliefs that it is an environmental issue. Level of support was also investigated as a perceptual filter that facilitates biased issue perceptions and affective evaluations of economic benefit and environmental cost frames presented in visual content of hydraulic fracturing. Results suggested an interactive relationship between visual framing and level of support, pointing to a substantial barrier to common understanding about the issue that strategic communicators should consider. PMID:26399946

  17. 7 CFR 2902.10 - Mobile equipment hydraulic fluids.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Comprehensive Procurement Guideline, 40 CFR 247.11. ... 7 Agriculture 15 2011-01-01 2011-01-01 false Mobile equipment hydraulic fluids. 2902.10 Section... PROCUREMENT Designated Items § 2902.10 Mobile equipment hydraulic fluids. (a) Definition. Hydraulic...

  18. 7 CFR 3201.10 - Mobile equipment hydraulic fluids.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Comprehensive Procurement Guideline, 40 CFR 247.11. ... 7 Agriculture 15 2013-01-01 2013-01-01 false Mobile equipment hydraulic fluids. 3201.10 Section... PROCUREMENT Designated Items § 3201.10 Mobile equipment hydraulic fluids. (a) Definition. Hydraulic...

  19. 7 CFR 3201.10 - Mobile equipment hydraulic fluids.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Comprehensive Procurement Guideline, 40 CFR 247.11. ... 7 Agriculture 15 2012-01-01 2012-01-01 false Mobile equipment hydraulic fluids. 3201.10 Section... PROCUREMENT Designated Items § 3201.10 Mobile equipment hydraulic fluids. (a) Definition. Hydraulic...

  20. 7 CFR 3201.10 - Mobile equipment hydraulic fluids.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Comprehensive Procurement Guideline, 40 CFR 247.11. ... 7 Agriculture 15 2014-01-01 2014-01-01 false Mobile equipment hydraulic fluids. 3201.10 Section... PROCUREMENT Designated Items § 3201.10 Mobile equipment hydraulic fluids. (a) Definition. Hydraulic...

  1. 14 CFR 33.72 - Hydraulic actuating systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic actuating systems. 33.72 Section... AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.72 Hydraulic actuating systems. Each hydraulic actuating system must function properly under all conditions in which...

  2. 7 CFR 2902.10 - Mobile equipment hydraulic fluids.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Comprehensive Procurement Guideline, 40 CFR 247.11. ... 7 Agriculture 15 2010-01-01 2010-01-01 false Mobile equipment hydraulic fluids. 2902.10 Section... PROCUREMENT Designated Items § 2902.10 Mobile equipment hydraulic fluids. (a) Definition. Hydraulic...

  3. 23 CFR 650.111 - Location hydraulic studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... § 650.111 (c) and (d) shall be summarized in environmental review documents prepared pursuant to 23 CFR... 23 Highways 1 2010-04-01 2010-04-01 false Location hydraulic studies. 650.111 Section 650.111... BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains §...

  4. Designing Online Courses: A Taxonomy to Guide Strategic Use of Features Available in Course Management Systems (CMS) in Distance Education

    ERIC Educational Resources Information Center

    Koszalka, Tiffany A.; Ganesan, Radha

    2004-01-01

    Course developers can be distracted from applying sound instructional design principles by the amount of flexibility offered through online course development resources (Kidney & Puckett, "Quarterly Review of Distance Education," 4 (2003), 203-212). Distance education course management systems (CMS) provide multiple features that can be easily…

  5. The Pedagogical, Linguistic, and Content Features of Popular English Language Learning Websites in China: A Framework for Analysis and Design

    ERIC Educational Resources Information Center

    Kettle, Margaret; Yuan, Yifeng; Luke, Allan; Ewing, Robyn; Shen, Huizhong

    2012-01-01

    As increasing numbers of Chinese language learners choose to learn English online, there is a need to investigate popular websites and their language learning designs. This paper reports on the first stage of a study that analyzed the pedagogical, linguistic, and content features of 25 Chinese English Language Learning (ELL) websites ranked…

  6. Assessment of severe accident prevention and mitigation features: BWR (boiling water reactor), Mark I containment design

    SciTech Connect

    Pratt, W.T.; Eltawila, F.; Perkins, K.R.; Fitzpatrick, R.G.; Luckas, W.J.; Lehner, J.R.; Davis, P.

    1988-07-01

    Plant features and operator actions, which have been found to be important in either preventing or mitigating severe accidents in BWRs with Mark I containments (BWR Mark I's) have been identified. These features and actions were developed from insights derived from reviews of in-depth risk assessments performed specifically for the Peach Bottom plant and from assessment of other relevant studies. Accident sequences that dominate the core-damage frequency and those accident sequences that are of potentially high consequence were identified. Vulnerabilities of the BWR Mark I to severe accident containment loads were also identified. In addition, those features of a BWR Mark I, which are important for preventing core damage and are available for mitigating fission-product release to the environment were also identified. This report is issued to provide focus to an analyst examining an individual plant. This report calls attention to plant features and operator actions and provides a list of deterministic attributes for assessing those features and actions found to be helpful in reducing the overall risk for Peach Bottom and other Mark I plants. Thus, the guidance is offered as a resource in examining the subject plant to determine if the same, or similar, plant features and operator actions will be of value in reducing overall plant risk. This report is intended to serve solely as guidance.

  7. Application of systems engineering techniques to component design - Capturing functionality and linking part 'critical to quality' features to requirements

    SciTech Connect

    Patel, C. M.; Moorby, J. S.; Sulley, J. L.

    2012-07-01

    A systems engineering approach - focusing upon functionality - has predominantly been applied in industry to the design of complex systems with many functional interactions, inputs and outputs, eg the design of a decay heat removal system. This paper presents how systems engineering techniques can be applied to component design, i.e. treating the component as a system in its own right, and using functionality as the 'bridge' between the customer requirements and accepted performance. A pressure relief valve is used as an example to present the techniques of: Functional Modelling to establish the functional requirements and Functional Failure Modes and Effects Analysis to establish any emergent functionality to reduce the risk of adverse behaviour. A key aspect of component design is capturing the design intent and establishing the 'Critical to Quality 'features that can critically affect quality and performance. This paper details 'Quality Function Deployment' being applied to a component to capture such features and to establish a clear link to the overarching performance requirements. This approach is particularly useful in ensuring continuity of design understanding throughout the component life cycle, assessing the effects of any proposed changes to the design and the effects of changes in system or customer requirements, or for using the design in a different application. (authors)

  8. The design features of the body of the portable electrocardiograph «ECG-EXPRESS»

    NASA Astrophysics Data System (ADS)

    Seryakov, V.; Khmelevsky, Yu; Mamontov, G.

    2015-10-01

    The sequence of the industrial product shaping is specified, the main modeling characteristics of the configuration and some of its parts are designated subject to the electrocardiograph design and the technologies used for the production of its body.

  9. Trends in Culturally Relevant Interface Design Features for Latino Web Site Users

    ERIC Educational Resources Information Center

    Sachau, Lori L.; Hutchinson, Susan R.

    2012-01-01

    There is a lack of published research on designing Web-based instruction for the adult U.S. Latino population. Instructional designers need guidance on how to design culturally relevant learning environments for this audience, particularly for Latino people from Mexican heritage. The authors used content analysis to investigate the extent to which…

  10. Simulation study to determine the impact of different design features on design efficiency in discrete choice experiments

    PubMed Central

    Vanniyasingam, Thuva; Cunningham, Charles E; Foster, Gary; Thabane, Lehana

    2016-01-01

    Objectives Discrete choice experiments (DCEs) are routinely used to elicit patient preferences to improve health outcomes and healthcare services. While many fractional factorial designs can be created, some are more statistically optimal than others. The objective of this simulation study was to investigate how varying the number of (1) attributes, (2) levels within attributes, (3) alternatives and (4) choice tasks per survey will improve or compromise the statistical efficiency of an experimental design. Design and methods A total of 3204 DCE designs were created to assess how relative design efficiency (d-efficiency) is influenced by varying the number of choice tasks (2–20), alternatives (2–5), attributes (2–20) and attribute levels (2–5) of a design. Choice tasks were created by randomly allocating attribute and attribute level combinations into alternatives. Outcome Relative d-efficiency was used to measure the optimality of each DCE design. Results DCE design complexity influenced statistical efficiency. Across all designs, relative d-efficiency decreased as the number of attributes and attribute levels increased. It increased for designs with more alternatives. Lastly, relative d-efficiency converges as the number of choice tasks increases, where convergence may not be at 100% statistical optimality. Conclusions Achieving 100% d-efficiency is heavily dependent on the number of attributes, attribute levels, choice tasks and alternatives. Further exploration of overlaps and block sizes are needed. This study's results are widely applicable for researchers interested in creating optimal DCE designs to elicit individual preferences on health services, programmes, policies and products. PMID:27436671

  11. Perception Of "Features" And "Objects": Applications To The Design Of Instrument Panel Displays

    NASA Astrophysics Data System (ADS)

    Poynter, Douglas; Czarnomski, Alan J.

    1988-10-01

    An experiment was conducted to determine whether socalled feature displays allow for faster and more accurate processing compared to object displays. Previous psychological studies indicate that features can be processed in parallel across the visual field, whereas objects must be processed one at a time with the aid of attentional focus. Numbers and letters are examples of objects; line orientation and color are examples of features. In this experiment, subjects were asked to search displays composed of up to 16 elements for the presence of specific elements. The ability to detect, localize, and identify targets was influenced by display format. Digital errors increased with the number of elements, the number of targets, and the distance of the target from the fixation point. Line orientation errors increased only with the number of targets. Several other display types were evaluated, and each produced a pattern of errors similar to either digital or line orientation format. Results of the study were discussed in terms of Feature Integration Theory, which distinguishes between elements that are processed with parallel versus serial mechanisms.

  12. One Feature of Adaptive Lesson Study in Thailand: Designing a Learning Unit

    ERIC Educational Resources Information Center

    Inprasitha, Maitree

    2011-01-01

    In Thailand, the Center for Research in Mathematics Education (CRME) has been implementing Japanese Lesson Study (LS) since 2002. An adaptive feature of this implementation was the incorporation of four phases of the Open Approach as a teaching approach within the three steps of the LS process. Four phases of this open approach are: 1) Posing…

  13. The Multi-Feature Hypothesis: Connectionist Guidelines for L2 Task Design

    ERIC Educational Resources Information Center

    Moonen, Machteld; de Graaff, Rick; Westhoff, Gerard; Brekelmans, Mieke

    2014-01-01

    This study focuses on the effects of task type on the retention and ease of activation of second language (L2) vocabulary, based on the multi-feature hypothesis (Moonen, De Graaff, & Westhoff, 2006). Two tasks were compared: a writing task and a list-learning task. It was hypothesized that performing the writing task would yield higher…

  14. Workshop on Instructional Features and Instructor/Operator Station Design for Training Systems.

    ERIC Educational Resources Information Center

    Ricard, G. L., Ed.; And Others

    These 19 papers review current research and development work related to the operation of the instructor's station of training systems, with emphasis on developing functional station specifications applicable to a variety of simulation-based training situations. Topics include (1) instructional features; (2) instructor/operator station research and…

  15. Design Features Of K = 100 Cyclotron Magnet For ISOL RIB Production

    SciTech Connect

    Park, Jin Ah; Gad, Kh. M. M.; Chai, Jong-Seo

    2011-06-01

    K = 100 Separated Sector Cyclotron was designed in conceptual for the ISOL driver. It has 4 separated sector magnets. Two SF cyclotrons will be used as the injectors for separated sector cyclotron. RF frequency is 70 MHz, 4th harmonics. We have designed sector magnet without trim and harmonic coils. Minimum radius of the magnet is 55 cm and maximum radius is 1.8 m. Designed magnets were calculated and simulated by OPERA 3D (TOSCA) code. Ion beam dynamics calculations have been done using particle studio code to prove the focusing properties of the designed magnets.

  16. Design Models as Emergent Features: An Empirical Study in Communication and Shared Mental Models in Instructional

    ERIC Educational Resources Information Center

    Botturi, Luca

    2006-01-01

    This paper reports the results of an empirical study that investigated the instructional design process of three teams involved in the development of an e-­learning unit. The teams declared they were using the same fast-­prototyping design and development model, and were composed of the same roles (although with a different number of SMEs).…

  17. Concept design and alternate arrangements of orbiter mid-deck habitability features

    NASA Technical Reports Server (NTRS)

    Church, R. A.; Ciciora, J. A.; Porter, K. L.; Stevenson, G. E.

    1976-01-01

    The evaluations and recommendations for habitability features in the space shuttle orbiter mid-deck are summarized. The orbiter mission plans, the mid-deck dimensions and baseline arrangements along with crew compliments and typical activities were defined. Female and male anthropometric data based on zero-g operations were also defined. Evaluations of baseline and alternate feasible concepts provided several recommendations which are discussed.

  18. Features of design and development of the optical head of star tracker

    NASA Astrophysics Data System (ADS)

    Moldabekov, M.; Akhmedov, D.; Yelubayev, S.; Ten, V.; Albazarov, B.; Shamro, Alexander; Alipbayev, Kuanysh; Bopeyev, Timur; Sukhenko, A.

    2014-10-01

    The paper presents an approach to the design and development of the optical head of the star tracker and its hood for satellites. The main stages of the optical system design including development of requirements, selection of the optical system by analyzing with help of CAD, hood design with help of simulation, as well as the main stages of its components(lenses) manufacturing and control of quality of manufacturing the optical system are described. Engineering model of the optical head of star tracker which can be used as the basis for the development of the star tracker prototype for use in Kazakhstan's satellites was developed in accordance with the requirements.

  19. Time domain responses of hydraulic bushing with two flow passages

    NASA Astrophysics Data System (ADS)

    Chai, Tan; Dreyer, Jason T.; Singh, Rajendra

    2014-02-01

    Hydraulic bushings are commonly employed in vehicle suspension and body sub-frame systems to control motion, vibration, and structure-borne noise. Since literature on this topic is sparse, a controlled bushing prototype which accommodates a combination of long and short flow passages and flow restriction elements is first designed, constructed and instrumented. Step-up and step-down responses of several typical fluid-filled bushing configurations are measured along with steady harmonic time histories of transmitted force and internal pressures. To analyze the experimental results and gain physical insights into the hydraulic bushing system, lumped system models of bushings with different design features are developed, and analytical expressions of transmitted force and internal pressure responses are derived by using the convolution method. Parametric studies are also conducted to examine the effect of hydraulic element parameters. System parameters are successfully estimated for both harmonic and step responses using theory and measurements, and the dynamic force measurements are analyzed using analytical predictions. Finally, some nonlinearities of the system are also observed, and the fluid resistance of flow passage is found to be the most nonlinear element.

  20. A Single-Vector Force Calibration Method Featuring the Modern Design of Experiments

    NASA Technical Reports Server (NTRS)

    Parker, P. A.; Morton, M.; Draper, N.; Line, W.

    2001-01-01

    This paper proposes a new concept in force balance calibration. An overview of the state-of-the-art in force balance calibration is provided with emphasis on both the load application system and the experimental design philosophy. Limitations of current systems are detailed in the areas of data quality and productivity. A unique calibration loading system integrated with formal experimental design techniques has been developed and designated as the Single-Vector Balance Calibration System (SVS). This new concept addresses the limitations of current systems. The development of a quadratic and cubic calibration design is presented. Results from experimental testing are compared and contrasted with conventional calibration systems. Analyses of data are provided that demonstrate the feasibility of this concept and provide new insights into balance calibration.

  1. Structural features and molecular aggregations of designed triple-stranded β-sheets in single crystals.

    PubMed

    Bandyopadhyay, Anupam; Misra, Rajkumar; Gopi, Hosahudya N

    2016-04-01

    Design, synthesis and single-crystal conformations of hybrid triple-stranded β-sheets composed of E-vinylogous residues are reported. Restricting conformational flexibility of β-strands through the insertion of carbon-carbon double bonds at facing positions leads to increased peptide crystallinity, which allowed unambiguous structural characterization of three-stranded β-sheets. This strategy can be further explored for the design of functional β-sheets. PMID:26980261

  2. Electric-hydraulic car

    SciTech Connect

    Clark, R.W.; Greene, H.

    1993-07-27

    A propulsion system is described for a vehicle having a chassis and at least one drive wheel, the propulsion system including in combination: a constant speed power source comprising an alternating current electric motor operated at a constant speed corresponding to its optimum performance; a source of energy comprising a storage battery and an inverter connected to the electric motor for operating the electric motor of the constant speed power source; a hydraulic fluid system including a main hydraulic pump coupled with the electric motor of the constant speed power source and driven thereby; at least one hydraulic drive motor coupled with the hydraulic pump for receiving fluid flow therefrom; and means for varying the fluid flow through the main hydraulic pump to vary the speed of operation of the hydraulic drive motor.

  3. Conceptual design features of the Kalimer-600 sodium cooled fast reactor

    SciTech Connect

    Hahn, Dohee; Kim, Yeong-Il; Kim, Seong-O; Lee, Jae-Han; Lee, Yong-Bum; Jeong, Hae-Yong

    2007-07-01

    An advanced sodium cooled fast reactor concept, KALIMER-600, has been developed by the Korea Atomic Energy Research Institute to satisfy the Gen-IV technology goals of sustainability, safety and reliability, economics and proliferation resistance. The concept enables an efficient utilization of uranium resources and a reduction of the radioactive waste. The core design has been developed with a strong emphasis on a proliferation resistance by adopting a single enrichment fuel without blanket assemblies. In addition, a passive residual heat removal system, shortened intermediate heat-transport system piping and seismic isolation have been realized in the reactor system design as enhancements to its safety and economics. The inherent safety characteristics of the KALIMER-600 design were verified through a safety analysis of its bounding events. The results for various unprotected events imply that the KALIMER-600 design can accommodate all the analyzed ATWS events. This self-regulation capability of the power without a scram is mainly attributed to the inherent reactivity feedback mechanisms implemented in the metal fuel core design and completely passive decay heat removal system. (authors)

  4. An insight into the features of the OAO-C thermal design.

    NASA Technical Reports Server (NTRS)

    Fine, H.; Quadrini, J.; Ollendorf, S.

    1973-01-01

    The Orbiting Astronomical Observatory (OAO)-C was successfully launched into a 400-nautical mile circular orbit on Aug. 21, 1972. For this spacecraft, a unique sensitivity approach to the thermal design was developed which resulted in a predictable design - the merits of which should be considered for application on future spacecraft. The OAO-C is also serving as a test bed for the evaluation of thermal control hardware. To provide flight data for space program applications, experiments for a new coating and four different heat pipe designs are on this spacecraft. The data derived from OAO-C will be extremely valuable for such future programs as the Large Space Telescope (LST) and the Earth Observation Satellite (EOS).

  5. Design Features Of Microfluidic Reactor For [18F]FDG Radiopharmaceutical Synthesis

    NASA Astrophysics Data System (ADS)

    Oh, J. H.; Lee, B. N.; Nam, K. R.; Attla, G. A.; Lee, K. C.; Cjai, J. S.

    2011-06-01

    Microfluidic reactor exhibits advantages for radiopharmaceutical synthesis. Microfluidic chips can reduce the time for radiosynthesis using tiny quantities of chemical compounds. It also has a good heat transfer, performance and provides an integrated system including synthesis, separation, and purification. These advantages make FDG production. So we have designed a microreactor chip which included the whole chemical processing; water evaporation, solvent exchange, radiofluorination and so on. It was designed by using a commercial 3D CAD modeling program CATIA V5, heat transfer performance was analyzed by ANSYS, and CFX was used for analyzing fluid performance. This paper described the design of FDG synthesis system on a microchip, the relevant locations of its parts, both heat and fluid performance efficiency analysis.

  6. Compression of Medical Images Using Enhanced Vector Quantizer Designed with Self Organizing Feature Maps

    NASA Astrophysics Data System (ADS)

    Dandawate, Yogesh H.; Joshi, Madhuri A.; Umrani, Shrirang

    Now a days all medical imaging equipments give output as digital image and non-invasive techniques are becoming cheaper, the database of images is becoming larger. This archive of images increases up to significant size and in telemedicine-based applications the storage and transmission requires large memory and bandwidth respectively. There is a need for compression to save memory space and fast transmission over internet and 3G mobile with good quality decompressed image, even though compression is lossy. This paper presents a novel approach for designing enhanced vector quantizer, which uses Kohonen's Self Organizing neural network. The vector quantizer (codebook) is designed by training with a neatly designed training image and by selective training approach .Compressing; images using it gives better quality. The quality analysis of decompressed images is evaluated by using various quality measures along with conventionally used PSNR.

  7. Impact of several reactor features on TF coil design for TPSS

    SciTech Connect

    Miller, J.R.

    1986-01-10

    Limits of acceptable radiation levels relative to winding pack current densities in the toroidal field (TF) coils is given for relevant reactor designs. Force cooled conductors are stipulated in this study. The maximum field which can be supported while maintaining adequate stability and the ability to protect the coils in the event of a quench to end of the machine life is reported to be 6T. TF configuration, winding pack design, heat removal, stability, copper fraction and effect of damage, limiting current, and protection are discussed. 12 refs., 2 tabs. (WRF)

  8. 23 CFR 650.115 - Design standards.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650.115 Design... metres) in volume or 25 feet (7.6 metres) deep, the hydrologic, hydraulic, and structural design of...

  9. GCFR thermal-hydraulic experiments

    SciTech Connect

    Schlueter, G.; Baxi, C.B.; Dalle Donne, M.; Gat, U.; Fenech, H.; Hanson, D.; Hudina, M.

    1980-01-01

    The thermal-hydraulic experimental studies performed and planned for the Gas-Cooled Fast Reactor (GCFR) core assemblies are described. The experiments consist of basic studies performed to obtain correlations, and bundle experiments which provide input for code validation and design verification. These studies have been performed and are planned at European laboratories, US national laboratories, Universities in the US, and at General Atomic Company

  10. Design features and operational characteristics of the Langley pilot transonic cryogenic tunnel

    NASA Technical Reports Server (NTRS)

    Kilgore, R. A.

    1974-01-01

    A fan-driven transonic cryogenic tunnel was designed, and its purging, cooldown, and warmup times were determined satisfactory. Cooling with liquid nitrogen is at the power levels required for transonic testing. Good temperature distributions are obtained by using a simple nitrogen injection system.

  11. How to Personalize Learning in K-12 Schools: Five Essential Design Features

    ERIC Educational Resources Information Center

    Lee, Dabae

    2014-01-01

    Personalized learning (PL) is spotlighted as a way to transform K-12 educational systems. PL customizes learning pace, instructional methods, and learning content to individual students. As much as PL sounds promising and complex, little guidance is available to educators and policymakers about how to effectively design PL. Five essential features…

  12. Use of Online Assessment Tools by Instructional Designers-by-Assignment: Necessary Features and Functionalities

    ERIC Educational Resources Information Center

    Halloran, Jo-Ann

    2013-01-01

    Government entities set criteria for institutions that have teacher educator programs to use online assessment tools to show continuous ongoing evaluation, and use data from the tools to guide the improvement of courses. The purpose of this qualitative, multi-case study was to discover how Instructional Designers-by-Assignment (IDBA) are using…

  13. Design Features of a Friendly Software Environment for Novice Programmers. Technical Report No. 3.

    ERIC Educational Resources Information Center

    Eisenstadt, Marc

    This paper describes the results of a 6-year period of design, implementation, testing, and iterative redesign of a programming language, user aids, and curriculum materials for use by psychology students learning how to write simple computer programs. The SOLO language, which was the resulting product, is primarily a simple, database…

  14. Thermally Actuated Hydraulic Pumps

    NASA Technical Reports Server (NTRS)

    Jones, Jack; Ross, Ronald; Chao, Yi

    2008-01-01

    Thermally actuated hydraulic pumps have been proposed for diverse applications in which direct electrical or mechanical actuation is undesirable and the relative slowness of thermal actuation can be tolerated. The proposed pumps would not contain any sliding (wearing) parts in their compressors and, hence, could have long operational lifetimes. The basic principle of a pump according to the proposal is to utilize the thermal expansion and contraction of a wax or other phase-change material in contact with a hydraulic fluid in a rigid chamber. Heating the chamber and its contents from below to above the melting temperature of the phase-change material would cause the material to expand significantly, thus causing a substantial increase in hydraulic pressure and/or a substantial displacement of hydraulic fluid out of the chamber. Similarly, cooling the chamber and its contents from above to below the melting temperature of the phase-change material would cause the material to contract significantly, thus causing a substantial decrease in hydraulic pressure and/or a substantial displacement of hydraulic fluid into the chamber. The displacement of the hydraulic fluid could be used to drive a piston. The figure illustrates a simple example of a hydraulic jack driven by a thermally actuated hydraulic pump. The pump chamber would be a cylinder containing encapsulated wax pellets and containing radial fins to facilitate transfer of heat to and from the wax. The plastic encapsulation would serve as an oil/wax barrier and the remaining interior space could be filled with hydraulic oil. A filter would retain the encapsulated wax particles in the pump chamber while allowing the hydraulic oil to flow into and out of the chamber. In one important class of potential applications, thermally actuated hydraulic pumps, exploiting vertical ocean temperature gradients for heating and cooling as needed, would be used to vary hydraulic pressures to control buoyancy in undersea research

  15. Design features and operational characteristics of the Langley 0.3-meter transonic cryogenic tunnel

    NASA Technical Reports Server (NTRS)

    Kilgore, R. A.

    1976-01-01

    Experience with the Langley 0.3 meter transonic cryogenic tunnel, which is fan driven, indicated that such a tunnel presents no unusual design difficulties and is simple to operate. Purging, cooldown, and warmup times were acceptable and were predicted with good accuracy. Cooling with liquid nitrogen was practical over a wide range of operating conditions at power levels required for transonic testing, and good temperature distributions were obtained by using a simple liquid nitrogen injection system. To take full advantage of the unique Reynolds number capabilities of the 0.3 meter transonic tunnel, it was designed to accommodate test sections other than the original, octagonal, three dimensional test section. A 20- by 60-cm two dimensional test section was recently installed and is being calibrated. A two dimensional test section with self-streamlining walls and a test section incorporating a magnetic suspension and balance system are being considered.

  16. Salient mechanical design features of the proposed 17 meter diameter MACE imaging gamma-ray telescope

    NASA Astrophysics Data System (ADS)

    Suthar, R. L.; Guha, S.; Bandopadhyay, K.; Manjunatha, A.; Mishra, V. K.; Koul, R.; Bhat, C. L.

    2002-03-01

    A low-threshold energy, high-sensitivity gamma-ray telescope, MACE (for Major Atmospheric Cerenkov Experiment) is proposed to be built in India for explorations of gamma-ray sky in 100's keV - 10's GeV photon energy range, hitherto inaccessible from ground. This paper outlines the scientific motivation for this major telescope system and focuses on its mechanical design aspects.

  17. Housing Stakeholder Preferences for the “Soft” Features of Sustainable and Healthy Housing Design in the UK

    PubMed Central

    Prochorskaite, Agne; Couch, Chris; Malys, Naglis; Maliene, Vida

    2016-01-01

    It is widely recognised that the quantity and sustainability of new homes in the UK need to increase. However, it is important that sustainable housing is regarded holistically, and not merely in environmental terms, and incorporates elements that enhance the quality of life, health and well-being of its users. This paper focuses on the “soft” features of sustainable housing, that is, the non-technological components of sustainable housing and neighbourhood design that can impact occupants’ health and well-being. Aims of the study are to ascertain the relative level of importance that key housing stakeholders attach to these features and to investigate whether the opinions of housing users and housing providers are aligned with regards to their importance. An online survey was carried out to gauge the level of importance that the key stakeholders, such as housing users, local authorities, housing associations, and developers (n = 235), attach to these features. Results revealed that while suitable indoor space was the feature regarded as most important by all stakeholders, there were also a number of disparities in opinion between housing users and housing providers (and among the different types of providers). This implies a scope for initiatives to achieve a better alignment between housing users and providers. PMID:26751465

  18. Thermal-hydraulic modeling needs for passive reactors

    SciTech Connect

    Kelly, J.M.

    1997-07-01

    The U.S. Nuclear Regulatory Commission has received an application for design certification from the Westinghouse Electric Corporation for an Advanced Light Water Reactor design known as the AP600. As part of the design certification process, the USNRC uses its thermal-hydraulic system analysis codes to independently audit the vendor calculations. The focus of this effort has been the small break LOCA transients that rely upon the passive safety features of the design to depressurize the primary system sufficiently so that gravity driven injection can provide a stable source for long term cooling. Of course, large break LOCAs have also been considered, but as the involved phenomena do not appear to be appreciably different from those of current plants, they were not discussed in this paper. Although the SBLOCA scenario does not appear to threaten core coolability - indeed, heatup is not even expected to occur - there have been concerns as to the performance of the passive safety systems. For example, the passive systems drive flows with small heads, consequently requiring more precision in the analysis compared to active systems methods for passive plants as compared to current plants with active systems. For the analysis of SBLOCAs and operating transients, the USNRC uses the RELAP5 thermal-hydraulic system analysis code. To assure the applicability of RELAP5 to the analysis of these transients for the AP600 design, a four year long program of code development and assessment has been undertaken.

  19. Design Features and Initial RF Performance of a Gradient Hardened 17 GHz TW Linac Structure

    SciTech Connect

    Haimson, J.; Mecklenburg, B.

    2009-01-22

    To avoid surface erosion damage and to assist in studying RF breakdown thresholds in 17 GHz TW linac structures, a gradient hardened structure has been fabricated with high temperature brazed and machined stainless steel surfaces located in the peak E-field region of the beam apertures and the peak H-field regions of the input coupler cavity. The microwave design parameters and physical dimensions of this 22 cavity, 120 degree phase advance structure were chosen to allow the high gradient performance to be compared against a similar design all-copper structure that has been tested in a dual ring, power recirculating amplifier system. The final design parameters of the gradient hardened structure are discussed; the influence of stainless steel RF losses on the power buildup of the resonant ring and on the structure gradient distribution are described; waveforms are shown of the unique ability of the power amplifier to rapidly quench RF breakdown discharges in the linac structure by automatically sensing and redirecting the RF source power to a matched load; and preliminary test results during high power RF processing of the gradient hardened linac structure are presented.

  20. Design Features and Initial RF Performance of a Gradient Hardened 17 GHz TW Linac Structure

    NASA Astrophysics Data System (ADS)

    Haimson, J.; Mecklenburg, B.

    2009-01-01

    To avoid surface erosion damage and to assist in studying RF breakdown thresholds in 17 GHz TW linac structures, a gradient hardened structure has been fabricated with high temperature brazed and machined stainless steel surfaces located in the peak E-field region of the beam apertures and the peak H-field regions of the input coupler cavity. The microwave design parameters and physical dimensions of this 22 cavity, 120 degree phase advance structure were chosen to allow the high gradient performance to be compared against a similar design all-copper structure that has been tested in a dual ring, power recirculating amplifier system. The final design parameters of the gradient hardened structure are discussed; the influence of stainless steel RF losses on the power buildup of the resonant ring and on the structure gradient distribution are described; waveforms are shown of the unique ability of the power amplifier to rapidly quench RF breakdown discharges in the linac structure by automatically sensing and redirecting the RF source power to a matched load; and preliminary test results during high power RF processing of the gradient hardened linac structure are presented.

  1. Experimental and design experience with passive safety features of liquid metal reactors

    SciTech Connect

    Lucoff, D.M.; Waltar, A.E.; Sackett, J.I.; Salvatores, M.; Aizawa, K.

    1992-10-01

    Liquid metal cooled reactors (LMRs) have already been demonstrated to be robust machines. Many reactor designers now believe that it is possible to include in this technology sufficient passive safety that LMRs would be able to survive loss of flow, loss of heat sink, and transient overpower events, even if the plant protective system fails completely and do so without damage to the core. Early whole-core testing in Rapsodie, EBR-II. and FFTF indicate such designs may be possible. The operational safety testing program in EBR-II is demonstrating benign response of the reactor to a full range of controls failures. But additional testing is needed if transient core structural response under major accident conditions is to be properly understood. The proposed international Phase IIB passive safety tests in FFTF, being designed with a particular emphasis on providing, data to understand core bowing extremes, and further tests planned in EBR-II with processed IFR fuel should provide a substantial and unique database for validating the computer codes being used to simulate postulated accident conditions.

  2. Experimental and design experience with passive safety features of liquid metal reactors

    SciTech Connect

    Lucoff, D.M.; Waltar, A.E. ); Sackett, J.I. ); Aizawa, K. )

    1992-07-01

    Liquid metal cooled reactors (LMRs) have already been demonstrated to be robust machines. Many reactor designers now believe that it is possible to include in this technology sufficient passive safety that LMRs would be able to survive loss of flow, loss of heat sink, and transient overpower events, even if the plant protective system fails completely--and do so without damage to the core. Early whole-core testing in Rapsodie, EBR-II, and FFTF indicate such designs may be possible. The operational safety testing program in EBR-II is demonstrating benign response of the reactor to a full range on controls failures. But additional testing is needed if transient core structural response under major accident conditions is to be properly understood. The proposed international Phase IIB passive safety tests in FFTF, being designed with a particular emphasis on providing data to understand core bowing extremes, and further tests planned in EBR-II with processed IFR fuel should provide a substantial and unique database for validating the computer codes being used to simulate postulated accident conditions.

  3. Impact of several reactor features on TF coil design for TPSS

    SciTech Connect

    Miller, J.R.; Bulmer, R.H.

    1986-03-26

    A significant driver of machine size in previous designs was the amount of nuclear shielding placed between the blanket and the toroidal field (TF) coils to minimize the radiation heating and damage in these critical components. Of course the total amount of shielding is not arbitrary; it certainly must adequately suppress radiation outside the plant. However, if all of this shielding were contained inside the TF coils, several parameters (coil size and weight, maximum field at the windings, stored energy, etc.) would become inordinately large. Reducing the amount of shielding inside the TF coils and allowing the radiation load to climb to less ''conventional'' levels could pay big benefits in reducing the machine size, so long as the damage and heat load remain tolerable. Recent studies indicate that superconducting windings in TF coils can accept much higher heat loads than have been previously considered and simultaneously can be designed with higher than conventional current densities. The purpose of the present exercise is to probe the limits of acceptable radiation levels in relation to winding pack current densities in the TF coils for reactor relevant designs.

  4. A non-intuitive design of a cyclic decapeptide library with unique backbone structural features.

    PubMed

    Paul, P K C

    2003-12-01

    An analysis of hydrogen bonding patterns of cyclic decapeptide (CDP) beta-sheet structures has resulted in a 'non-intuitive' design of cyclic decapeptides wherein their beta-turns and residue positions can be fixed by choosing 2 of the 10 residues, i.e. positions i and i+4, to be Prolines or N-substituted residues. This sequence relationship between the two Pro or N-substituted residues is shown to uniquely define the conformation of the CDP. Furthermore, this design of the 2 beta-turn, beta-sheet CDP structure is expected to be characterised by residues disposed in an exclusive fashion in which four residues are on one side of the ring, two on the other and the four corner residues in the beta-turn are in the plane of the ring. This opens up the possibility of fine-tuning the four residues facing one way and /or the two residues facing the other way such that a library containing a myriad of chemically diverse systems could be obtained. The design process along with the molecular modelling of specific CDP-s and the building of a CDP library are discussed in detail. PMID:14683511

  5. Analysis of mobile phone design features affecting radiofrequency power absorbed in a human head phantom.

    PubMed

    Kuehn, Sven; Kelsh, Michael A; Kuster, Niels; Sheppard, Asher R; Shum, Mona

    2013-09-01

    The US FCC mandates the testing of all mobile phones to demonstrate compliance with the rule requiring that the peak spatial SAR does not exceed the limit of 1.6 W/kg averaged over any 1 g of tissue. These test data, measured in phantoms with mobile phones operating at maximum antenna input power, permitted us to evaluate the variation in SARs across mobile phone design factors such as shape and antenna design, communication technology, and test date (over a 7-year period). Descriptive statistical summaries calculated for 850 MHz and 1900 MHz phones and ANOVA were used to evaluate the influence of the foregoing factors on SARs. Service technology accounted for the greatest variability in compliance test SARs that ranged from AMPS (highest) to CDMA, iDEN, TDMA, and GSM (lowest). However, the dominant factor for SARs during use is the time-averaged antenna input power, which may be much less than the maximum power used in testing. This factor is largely defined by the communication system; e.g., the GSM phone average output can be higher than CDMA by a factor of 100. Phone shape, antenna type, and orientation of a phone were found to be significant but only on the order of up to a factor of 2 (3 dB). The SAR in the tilt position was significantly smaller than for touch. The side of the head did not affect SAR levels significantly. Among the remaining factors, external antennae produced greater SARs than internal ones, and brick and clamshell phones produced greater SARs than slide phones. Assuming phone design and usage patterns do not change significantly over time, we have developed a normalization procedure and formula that permits reliable prediction of the relative SAR between various communication systems. This approach can be applied to improve exposure assessment in epidemiological research. PMID:23533135

  6. Identifying heavy-ion-beam fusion design and system features with high economic leverage

    SciTech Connect

    Meier, W.R.; Hogan, W.J.

    1985-03-03

    We have conducted parametric economic studies for heavy-ion-beam fusion electric power plants. We examined the effects on the cost of electricity of several design parameters: maximum achievable chamber pulse rate, driver cost, target gain, and electric conversion efficiency, and net electric power. We found with reasonable assumptions on driver cost, target gain, and electric conversion efficiency, a 2 to 3 GWe heavy-ion-beam fusion power plant, with a chamber pulse rate of 5 to 10 Hz, can be competitive with nuclear and coal power plants.

  7. Design and experimental evaluation of a tactile display featuring magnetorheological fluids

    NASA Astrophysics Data System (ADS)

    Han, Young-Min; Oh, Jong-Seok; Kim, Jin-Kuy; Choi, Seung-Bok

    2014-07-01

    This paper proposes a novel type of tactile display utilizing magnetorheological (Mr) fluid which can be applied to a robotic system in minimally invasive surgery to provide a surgeon with tactile information on remote biological tissues or organs. As a first step, an actuation mechanism for tactile function is devised utilizing the Mr fluid with a pin array mechanism. Based on the force responses of a human body, the tactile display is appropriately designed and a magnetic analysis is carried out to determine the design parameters using the finite element method. After evaluating the field-dependent force characteristics of the manufactured tactile display, a feed-forward control algorithm based on fuzzy logic is formulated to obtain the desired palpation force. Control performance is demonstrated via palpation force evaluation and psychophysical evaluation. In the results, the actual repulsive forces agreed well with the desired forces and the averaged relative error was less than 1.3%. In addition, the volunteers successfully recognized tactility with a favorable rating value of 3.36 on a five-point scale.

  8. Breakdown Features of Various Microstrip-Type Gas Counter Designs and Their Improvements

    NASA Technical Reports Server (NTRS)

    Peskov, V.; Ramsey, B. D.; Fonte, P.

    1998-01-01

    Breakdown mechanisms and spurious pulses, the precursors to some breakdowns, were studied experimentally for both uncoated and coated Microstrip Gas Counters (MSGCs) of different geometries, as well as for MicroGap Counters (MGCs) and for the "Compteur A Trou" (CAT). It was found that in all cases the breakdowns occurred through surface streamers, although the exact mechanism of streamer formation depended on the particular detector design. Based on these studies, new designs of microstrip detectors, in which the role of the substrate was minimized, were elaborated and tested. In some of these detectors, especially with large pitches (greater than 2mm), gains up to 2-3 x 10(exp 5) were achieved together with good rate characteristics. The ultimate gain limit in all geometries was still set by spark-inducing streamers which appeared at some critical charge density in the avalanche. To avoid this, and particularly to enhance the performance of small-pitch MSGCs, preamplification structures can be used. Utilizing a parallel plate avalanche chamber as a front end to an MSGC resulted in an overall gain of approximately 10(exp 6), limited in this case only by charge saturation.

  9. Downhole hydraulic seismic generator

    DOEpatents

    Gregory, Danny L.; Hardee, Harry C.; Smallwood, David O.

    1992-01-01

    A downhole hydraulic seismic generator system for transmitting energy wave vibrations into earth strata surrounding a borehole. The system contains an elongated, unitary housing operably connected to a well head aboveground by support and electrical cabling, and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a hydraulic oscillator containing a double-actuating piston whose movement is controlled by an electro-servovalve regulating a high pressure hydraulic fluid flow into and out of upper and lower chambers surrounding the piston. The spent hydraulic fluid from the hydraulic oscillator is stored and pumped back into the system to provide high pressure fluid for conducting another run at the same, or a different location within the borehole.

  10. Design and Performance Evaluation of a Linear Ion Trap Mass Analyzer Featuring Half Round Rod Electrodes

    NASA Astrophysics Data System (ADS)

    Li, Xiaoxu; Zhang, Xiaohua; Yao, Rujiao; He, Yang; Zhu, Yongyong; Qian, Jie

    2015-05-01

    A novel linear ion trap mass analyzer featuring half round rod electrodes (HreLIT) has been built. It is mainly composed of two pairs of stainless steel electrodes which have a cross-section of half round rod and a pair of end electrodes. The HreLIT has a simple structure and so it could be assembled by hand with relatively high mechanical accuracy. The external dimension of HreLIT is 50 mm × 29.5 mm × 28 mm (length × width × height) and its internal volume is about 3.8 cm3. A home-made HreLIT mass spectrometer with three-stage vacuum system was built and the performance of HreLIT was characterized using reserpine solution and PPG standard solution. When the scan rate was 254 u/s, mass peak with FWHM of 0.14 u was achieved for ions with m/z 609, which corresponds to a mass resolution of 4350. The HreLIT was also operated at a low q value of 0.28 to extend its mass range. The experiment result showed a mass range of over 2800 u and the amplitude of radio frequency (rf) signal was only 1560 V (0-p). Three-stage tandem mass spectrometry was successfully performed in the HreLIT, and the collision-induced dissociation (CID) efficiencies of MS2 (CID of ions with m/z 609) and MS3 (CID of ions with m/z 448) were 78% and 59%, respectively.

  11. Mid-sized omnidirectional robot with hydraulic drive and steering

    NASA Astrophysics Data System (ADS)

    Wood, Carl G.; Perry, Trent; Cook, Douglas; Maxfield, Russell; Davidson, Morgan E.

    2003-09-01

    Through funding from the US Army-Tank-Automotive and Armaments Command's (TACOM) Intelligent Mobility Program, Utah State University's (USU) Center for Self-Organizing and Intelligent Systems (CSOIS) has developed the T-series of omni-directional robots based on the USU omni-directional vehicle (ODV) technology. The ODV provides independent computer control of steering and drive in a single wheel assembly. By putting multiple omni-directional (OD) wheels on a chassis, a vehicle is capable of uncoupled translational and rotational motion. Previous robots in the series, the T1, T2, T3, ODIS, ODIS-T, and ODIS-S have all used OD wheels based on electric motors. The T4 weighs approximately 1400 lbs and features a 4-wheel drive wheel configuration. Each wheel assembly consists of a hydraulic drive motor and a hydraulic steering motor. A gasoline engine is used to power both the hydraulic and electrical systems. The paper presents an overview of the mechanical design of the vehicle as well as potential uses of this technology in fielded systems.

  12. Innovative Structural Design Features for a 10 m Solar Sail Demonstrator

    NASA Technical Reports Server (NTRS)

    Laue, G.; Moore, J.; Clayton, W.

    2004-01-01

    The successful development of sail architectures will require careful attention to a number of key issues including but not limited to material strength issues, stress conditions for the membrane, load interactions between membrane and structure, and membrane material planarity. Along with the inherent challenges of fabricating and handling very large membrane structures these issues will pose real challenges for the near-term development of practical sail technologies. SRS has developed innovative technologies that deal directly with the challenges of developing very large sail membranes. Some of these technologies include edge reinforcements and innovative reinforcement attachment techniques, production of flight durable sail materials of less than 2.5 micron thicknesses and large scale fabrication techniques. SRS has employed these technologies in several large 10 m demonstrators that have been delivered to LaRC for solar vacuum testing. Details of the design of this system will be discussed.

  13. Design features of the solenoid magnets for the central cell of the MFTF-B

    SciTech Connect

    Wohlwend, J.W.; Tatro, R.E.; Ring, D.S.

    1981-10-23

    The 14 superconducting solenoid magnets which form the central cell of the MFTF-B are being designed and fabricated by General Dynamics for the Lawrence Livermore National Laboratory. Each solenoid coil has a mean diameter of five meters and contains 600 turns of a proven conductor type. Structural loading resulting from credible fault events, cooldown and warmup requirements, and manufacturing processes consistent with other MFTF-B magnets have been considered in the selection of 304 LN as the structural material for the magnet. The solenoid magnets are connected by 24 intercoil beams and 20 solid struts which resist the longitudinal seismic and electromagnetic attractive forces and by 24 hanger/side supports which react magnet dead weight and seismic loads. A modular arrangement of two solenoid coils within a vacuum vessel segment allow for sequential checkout and installation.

  14. Special features of the CLUSTER antenna and radial booms design, development and verification

    NASA Technical Reports Server (NTRS)

    Gianfiglio, G.; Yorck, M.; Luhmann, H. J.

    1995-01-01

    CLUSTER is a scientific space mission to in-situ investigate the Earth's plasma environment by means of four identical spin-stabilized spacecraft. Each spacecraft is provided with a set of four rigid booms: two Antenna Booms and two Radial Booms. This paper presents a summary of the boom development and verification phases addressing the key aspects of the Radial Boom design. In particular, it concentrates on the difficulties encountered in fulfilling simultaneously the requirements of minimum torque ratio and maximum allowed shock loads at boom latching for this two degree of freedom boom. The paper also provides an overview of the analysis campaign and testing program performed to achieve sufficient confidence in the boom performance and operation.

  15. LVP modeling and dynamic characteristics prediction of a hydraulic power unit in deep-sea

    NASA Astrophysics Data System (ADS)

    Cao, Xue-peng; Ye, Min; Deng, Bin; Zhang, Cui-hong; Yu, Zu-ying

    2013-03-01

    A hydraulic power unit (HPU) is the driving "heart" of deep-sea working equipment. It is critical to predict its dynamic performances in deep-water before being immerged in the seawater, while the experimental tests by simulating deep-sea environment have many disadvantages, such as expensive cost, long test cycles, and difficult to achieve low-temperature simulation, which is only used as a supplementary means for confirmatory experiment. This paper proposes a novel theoretical approach based on the linear varying parameters (LVP) modeling to foresee the dynamic performances of the driving unit. Firstly, based on the varying environment features, dynamic expressions of the compressibility and viscosity of hydraulic oil are derived to reveal the fluid performances changing. Secondly, models of hydraulic system and electrical system are accomplished respectively through studying the control process and energy transfer, and then LVP models of the pressure and flow rate control is obtained through the electro-hydraulic models integration. Thirdly, dynamic characteristics of HPU are obtained by the model simulating within bounded closed sets of varying parameters. Finally, the developed HPU is tested in a deep-sea imitating hull, and the experimental results are well consistent with the theoretical analysis outcomes, which clearly declare that the LVP modeling is a rational way to foresee dynamic performances of HPU. The research approach and model analysis results can be applied to the predictions of working properties and product designs for other deep-sea hydraulic pump.

  16. Design and operating features of the high-level waste vitrification system for the West Valley demonstration project

    SciTech Connect

    Siemens, D.H.; Beary, M.M.; Barnes, S.M.; Berger, D.N.; Brouns, R.A.; Chapman, C.C.; Jones, R.M.; Peters, R.D.; Peterson, M.E.

    1986-03-01

    A liquid-fed joule-heated ceramic melter system is the reference process for immobilization of the high-level liquid waste in the US and several foreign countries. This system has been under development for over ten years at Pacific Northwest Laboratory and other national laboratories operated for the US Department of Energy. Pacific Northwest Laboratory contributed to this research through its Nuclear Waste Treatment Program and used applicable data to design and test melters and related systems using remote handling of simulated radioactive wastes. This report describes the equipment designed in support of the high-level waste vitrification program at West Valley, New York. Pacific Northwest Laboratory worked closely with West Valley Nuclear Services Company to design a liquid-fed ceramic melter, a liquid waste preparation and feed tank and pump, an off-gas treatment scrubber, and an enclosed turntable for positioning the waste canisters. Details of these designs are presented including the rationale for the design features and the alternatives considered.

  17. 7 CFR 3201.28 - Stationary equipment hydraulic fluids.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... designation can be found in the Comprehensive Procurement Guideline, 40 CFR 247.11. EPA provides recovered... 7 Agriculture 15 2013-01-01 2013-01-01 false Stationary equipment hydraulic fluids. 3201.28... FEDERAL PROCUREMENT Designated Items § 3201.28 Stationary equipment hydraulic fluids. (a)...

  18. 7 CFR 2902.28 - Stationary equipment hydraulic fluids.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... designation can be found in the Comprehensive Procurement Guideline, 40 CFR 247.11. EPA provides recovered... 7 Agriculture 15 2011-01-01 2011-01-01 false Stationary equipment hydraulic fluids. 2902.28... PROCUREMENT Designated Items § 2902.28 Stationary equipment hydraulic fluids. (a) Definition....

  19. 7 CFR 3201.28 - Stationary equipment hydraulic fluids.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... designation can be found in the Comprehensive Procurement Guideline, 40 CFR 247.11. EPA provides recovered... 7 Agriculture 15 2012-01-01 2012-01-01 false Stationary equipment hydraulic fluids. 3201.28... FEDERAL PROCUREMENT Designated Items § 3201.28 Stationary equipment hydraulic fluids. (a)...

  20. 7 CFR 3201.28 - Stationary equipment hydraulic fluids.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... designation can be found in the Comprehensive Procurement Guideline, 40 CFR 247.11. EPA provides recovered... 7 Agriculture 15 2014-01-01 2014-01-01 false Stationary equipment hydraulic fluids. 3201.28... FEDERAL PROCUREMENT Designated Items § 3201.28 Stationary equipment hydraulic fluids. (a)...

  1. 7 CFR 2902.28 - Stationary equipment hydraulic fluids.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... designation can be found in the Comprehensive Procurement Guideline, 40 CFR 247.11. EPA provides recovered... 7 Agriculture 15 2010-01-01 2010-01-01 false Stationary equipment hydraulic fluids. 2902.28... PROCUREMENT Designated Items § 2902.28 Stationary equipment hydraulic fluids. (a) Definition....

  2. Design features of the A-cell and transition coils of MFTF-B

    SciTech Connect

    Tatro, R.E.; Wohlwend, J.W.; Ring, D.S.

    1981-10-23

    The MFTF-B transition coil and A-cell magnet designs use variations of the copper-stabilized NbTi conductor developed by LLNL for the MFTF Yin-Yang magnets. This conductor will be wound on the one inch thick (12.7 mm) stainless steel coil forms using a two-axis winding machine similar to the existing LLNL Yin-Yang winding machine. After winding, covers will be placed over the coil and welded to the coil form to form a helium-tight jacket around the conductor. These jacketed coils are then enclosed in thick structural cases that react the large Lorentz forces on the magnets. The space between the coil jacket and case will be filled by a stainless steel bladder that will be injected with urethane. The injection bladder will provide cooling passages during cooldown as well as transmitting the Lorentz forces between the jacket and the case. The large self-equilibrating lobe-spreading forces on the magnets (29.10/sup 6/ lb, 127.0 MN) for the A-cell are reacted primarily through the thick 304 LN case into the external superstructure. The net Lorentz forces and the inertial forces on the magnet are reacted through support systems into the LLNL vacuum vessel structure.

  3. Miniaturized, 9-12 micron heterodyne spectrometer with space qualifiable design features

    NASA Technical Reports Server (NTRS)

    Glenar, D. A.; Mumma, M. J.; Kostiuk, T.; Huffman, H.; Degnan, J.

    1990-01-01

    A demonstration-prototype CO2-laser heterodyne spectrometer operating at 9-12 microns and suitable for long-term space missions is described and illustrated with extensive diagrams, drawings, photographs, and graphs of test performance data. The spectrometer has total volume 0.63 cu m, mass 30 kg, and power requirement 60-70 W, compatible with miniature-class Space Shuttle experiment payload specifications. It comprises three modules: (1) an optical front end with reflecting optics, a 2-GHz BW HgCdTe photomixer, and a 0-2-GHz 40-dB RF preamplifier; (2) a local oscillator with an RF-excited waveguide CO2 laser, a 75-percent-efficiency RF amplifier, a stepper-driven grating mode selector, and an etalon stabilized for over 30,000 h of use; and (3) an RF-filter-bank spectral-line receiver with a 25-MHz RF channel, 1.6-GHz IF spectral coverage, onboard instrument control, a serial link to the host computer, and highly integrated design.

  4. Amorphous calcium phosphate offers improved crack resistance: a design feature from nature?

    PubMed

    Saber-Samandari, Saeed; Gross, Karlis A

    2011-12-01

    Amorphous calcium phosphate (ACP) is found in biological organisms and coated implants, used in calcium phosphate cements, and has been recently confirmed as a precursor in mineralized tissue; however, nothing is known about crack initiation in ACP or its fracture toughness. The objective of this study was to determine the crack resistance of ACP to help understand its role in biological organisms and assist in the design of calcium-phosphate-based implants. ACP was manufactured by quenching droplets to form a bulk sample and individual splats. Testing of Berkovich and cube-corner indenter types revealed that the Berkovich indenter was more suitable, providing ease of crack detection. Nanoindentation was performed on polished ACP and hydroxyapatite (HAp), and cracks were identified with scanning electron microscopy. Additional nanoindentation was done on splats to assess the suitability for testing microarrays used in high throughput discovery of new bioceramics. ACP required about three times more force to initiate a crack compared to sintered HAp, but about nine times more than a single crystal. Crack initiation resistance decreased with increasing grain size. The fracture toughness of ACP was comparable to a single crystal, but higher for nanograined HAp. The crack initiation load can be potentially used for evaluating microsized samples. ACP prevents crack formation, but requires the presence of nanograins to provide a greater toughness. The implications of the higher crack initiation load in ACP are discussed for biological organisms and thermally processed biomaterials such as thermally sprayed and sintered HAp. PMID:21784179

  5. Design of cyclic peptides featuring proline predominantly in the cis conformation under physiological conditions.

    PubMed

    Malešević, Miroslav; Schumann, Michael; Jahreis, Günther; Fischer, Gunter; Lücke, Christian

    2012-09-24

    Turns are secondary-structure elements that are omnipresent in natively folded polypeptide chains. A large variety of four-residue β-turns exist, which differ mainly in the backbone dihedral angle values of the two central residues i+1 and i+2. The βVI-type turns are of particular biological interest because the i+2 residue is always a proline in the cis conformation and might thus serve as target of peptidyl prolyl cis/trans isomerases (PPIases). We have designed cyclic hexapeptides containing two proline residues that predominantly adopt the cis conformation in aqueous solution. NMR data and MD calculations indicated that the cyclic peptide sequences c-(-DXaa-Ser-Pro-DXaa-Lys-Pro-) result in highly symmetric backbone structures when both prolines are in the cis conformation and the D-amino acids are either alanine or phenylalanine residues. Replacement of the serine residue either by phosphoserine or by tyrosine compromises this symmetry, but further increases the cis conformation content of both prolines. As a result, we obtained a cyclic hexapeptide that exists almost exclusively as the cis-Pro/cis-Pro conformer but shows no cis/trans interconversion even in the presence of the PPIase Pin1, apparently due to an energetically quite favorable but highly restricted conformational space. PMID:22969011

  6. The histological features of microwave coagulation therapy: an assessment of a new applicator design

    PubMed Central

    Swift, Benjamin; Strickland, Andrew; West, Kevin; Clegg, Peter; Cronin, Nigel; Lloyd, David

    2003-01-01

    Microwave ablation of tumours within the liver may become an adjunct or alternative to resection in patients with primary or secondary cancers. This technique combines the benefits of a large, localized coagulative effect with a single insertion of the applicator, in a significantly shorter time than comparable treatments. A new range of microwave applicators were developed and tested in animal models and both ex-vivo and in-vivo specimens of human liver at resection. At laparotomy, the applicator tip was inserted into normal liver parenchyma and tumours, with each specimen subjected to irradiation for 180 s or more and at varying power outputs. On sectioning an area of spherical blanching was observed around the applicator cavity. Microscopically a zone of coagulative necrosis was seen adjacent to the site of probe insertion. Damage to blood vessels and bile ducts occurred distal to the probe cavity suggesting the passage of heated fluid, a finding that was diminished by temporary occlusion of the hepatic vasculature (a Pringle manoeuvre). Ultra-structural damage was confirmed within the burn zone and selected liver enzymes were shown to be functioning beyond this region. We suggest this indicates the surrounding liver parenchyma is functioning normally and therefore the volume of microwave-induced damage is controllable. We are confident that the new applicator design will allow the effective treatment of larger tumours in a safe and controlled manner with a single application of energy. PMID:12694484

  7. Design, Synthesis, and Biological Features of Platinum(II) Complexes with Rigid Steric Hindrance.

    PubMed

    Wang, Zhimei; Yu, Haiyan; Gou, Shaohua; Chen, Feihong; Fang, Lei

    2016-05-01

    A series of platinum(II) complexes, with N-monosubstituted 1R,2R-diaminocyclohexane bearing methoxy-substituted benzyl groups as carrier ligands, were designed and synthesized. The newly prepared compounds, with chloride anions as leaving groups, were found to be very active against the tested cancer cell lines, including a cisplatin-resistant cell line. Despite their efficacy against tumor cells, they also showed low toxicity to a human normal liver cell line. Among them, complex 1 had superior cytotoxic activity against A549, HCT-116, MCF-7, SGC7901, and SGC7901/CDDP cancer cell lines. The DNA binding assay is of further special interest, as an unusual monofunctional binding mode was found, due to the introduction of a rigid substituted aromatic ring in the 1R,2R-diaminocyclohexane framework as steric hindrance. The linkage of complex 1 with DNA was stable and insensitive to nucleophilic attack. Moreover, studies including cellular uptake, gel electrophoresis, apoptosis and cell cycle, and Western blot analysis have provided insight into the high potency of this compound. PMID:27074104

  8. The rationale and design features for the 40 by 80/80 by 120 foot wind tunnel

    NASA Technical Reports Server (NTRS)

    Mort, K. W.; Kelly, M. W.; Hickey, D. H.

    1976-01-01

    A substantial increase in the test capability of full scale wind tunnels is considered. In order to determine the most cost effective means for providing this desired increase in test capability, a series of design studies were conducted of various new facilities as well as of major modifications to the existing 40- by 80-foot wind tunnel. The most effective trade between test capability and facility cost was provided by repowering the existing 40 by 80 foot wind tunnel to increase the maximum speed from 200 knots to 300 knots and by the addition of a new 80- by 120-foot test section having a 110 knot maximum speed. The design of the facility is described with special emphasis on the unique features, such as the drive system which absorbs nearly four times the power without an increase in noise, and the large flow diversion devices required to interface the two test sections to a single drive.

  9. Parametric identification of a servo-hydraulic actuator for real-time hybrid simulation

    NASA Astrophysics Data System (ADS)

    Qian, Yili; Ou, Ge; Maghareh, Amin; Dyke, Shirley J.

    2014-10-01

    In a typical Real-time Hybrid Simulation (RTHS) setup, servo-hydraulic actuators serve as interfaces between the computational and physical substructures. Time delay introduced by actuator dynamics and complex interaction between the actuators and the specimen has detrimental effects on the stability and accuracy of RTHS. Therefore, a good understanding of servo-hydraulic actuator dynamics is a prerequisite for controller design and computational simulation of RTHS. This paper presents an easy-to-use parametric identification procedure for RTHS users to obtain re-useable actuator parameters for a range of payloads. The critical parameters in a linearized servo-hydraulic actuator model are optimally obtained from genetic algorithms (GA) based on experimental data collected from various specimen mass/stiffness combinations loaded to the target actuator. The actuator parameters demonstrate convincing convergence trend in GA. A key feature of this parametric modeling procedure is its re-usability under different testing scenarios, including different specimen mechanical properties and actuator inner-loop control gains. The models match well with experimental results. The benefit of the proposed parametric identification procedure has been demonstrated by (1) designing an H∞ controller with the identified system parameters that significantly improves RTHS performance; and (2) establishing an analysis and computational simulation of a servo-hydraulic system that help researchers interpret system instability and improve design of experiments.

  10. Thermal enhancement cartridge heater modified tritium hydride bed development, Part 2 - Experimental validation of key conceptual design features

    SciTech Connect

    Heroux, K.J.; Morgan, G.A.

    2015-03-15

    The Thermal Enhancement Cartridge Heater Modified (TECH Mod) tritium hydride bed is an interim replacement for the first generation (Gen1) process hydride beds currently in service in the Savannah River Site (SRS) Tritium Facilities. 3 new features are implemented in the TECH Mod hydride bed prototype: internal electric cartridge heaters, porous divider plates, and copper foam discs. These modifications will enhance bed performance and reduce costs by improving bed activation and installation processes, in-bed accountability measurements, end-of-life bed removal, and He-3 recovery. A full-scale hydride bed test station was constructed at the Savannah River National Laboratory (SRNL) in order to evaluate the performance of the prototype TECH Mod hydride bed. Controlled hydrogen (H{sub 2}) absorption/ desorption experiments were conducted to validate that the conceptual design changes have no adverse effects on the gas transfer kinetics or H{sub 2} storage/release properties compared to those of the Gen1 bed. Inert gas expansions before, during, and after H{sub 2} flow tests were used to monitor changes in gas transfer rates with repeated hydriding/de-hydriding of the hydride material. The gas flow rates significantly decreased after initial hydriding of the material; however, minimal changes were observed after repeated cycling. The data presented herein confirm that the TECH Mod hydride bed would be a suitable replacement for the Gen1 bed with the added enhancements expected from the advanced design features. (authors)

  11. Electric versus hydraulic drives

    SciTech Connect

    Not Available

    1983-01-01

    This volume records the proceedings of a conference organised by the Engineering Manufacturing Industries Division of the Institution of Mechanical Engineers. Topics considered include high performance position control - a review of the current state of developments; hydrostatic drives - present and future; electric drives - present and future trends; electrical and hydraulic drives for heavy industrial robots; the development of an electro-mechanical tilt system for the advanced passenger train; industrial hydraulic ring mains - effective or efficient. the comparison of performance of servo feed-drive systems; overhead crane drives; the future of d.c. servodrives; the choice of actuator for military systems; linear electro-hydraulic actuators; and actuation for industrial robots.

  12. Controlling hydraulic system costs

    SciTech Connect

    Smiley, C.H.

    1982-06-01

    Hydraulic system preventive maintenance is largely a matter of using the senses and common logic to spot signs of impending problems. The ability to recognize a potential malfunction can save a great deal of money in repairs and lost production.

  13. Suspensions in hydraulic fracturing

    SciTech Connect

    Shah, S.N.

    1996-12-31

    Suspensions or slurries are widely used in well stimulation and hydraulic fracturing processes to enhance the production of oil and gas from the underground hydrocarbon-bearing formation. The success of these processes depends significantly upon having a thorough understanding of the behavior of suspensions used. Therefore, the characterization of suspensions under realistic conditions, for their rheological and hydraulic properties, is very important. This chapter deals with the state-of-the-art hydraulic fracturing suspension technology. Specifically it deals with various types of suspensions used in well stimulation and fracturing processes, their rheological characterization and hydraulic properties, behavior of suspensions in horizontal wells, review of proppant settling velocity and proppant transport in the fracture, and presently available measurement techniques for suspensions and their merits. Future industry needs for better understanding of the complex behavior of suspensions are also addressed. 74 refs., 21 figs., 1 tab.

  14. Hydraulic Actuator System for Rotor Control

    NASA Technical Reports Server (NTRS)

    Ulbrich, Heinz; Althaus, Josef

    1991-01-01

    In the last ten years, several different types of actuators were developed and fabricated for active control of rotors. A special hydraulic actuator system capable of generating high forces to rotating shafts via conventional bearings is addressed. The actively controlled hydraulic force actuator features an electrohydraulic servo valve which can produce amplitudes and forces at high frequencies necessary for influencing rotor vibrations. The mathematical description will be given in detail. The experimental results verify the theoretical model. Simulations already indicate the usefulness of this compact device for application to a real rotor system.

  15. Portable Hydraulic Powerpack

    NASA Technical Reports Server (NTRS)

    Anderson, L. A.; Henry, R. L.; Fedor, O. H.; Owens, L. J.

    1986-01-01

    Rechargeable hydraulic powerpack functions as lightweight, compact source of mechanical energy. Self-contained hydraulic powerpack derives energy from solid chemical charge. Combustion of charge initiated by small hammer, and revolving feeder replaces charges expended. Combustion gases cool during expansion in turbine and not too hot for release to atmosphere. Unit has applications driving wheelchairs and operating drills, winches, and other equipment in remote areas. Also replaces electric motors and internal-combustion engines as source of power in explosive atmospheres.

  16. Hydraulic motor for cars

    SciTech Connect

    Gagnon, D.C.

    1986-09-02

    A hydraulic motor for a car is described comprising, in combination, an automotive vehicle engine for travel self-propulsion, including a block, a plurality of cylinders in the block, a piston slidable in each cylinder, a crankshaft in the block, a piston rod connected between the crankshaft and each of the pistons, a power take-off gear on the crankshaft for the travel self-propulsion, and the engine including a hydraulic means for driving the pistons in the cylinders.

  17. Development of Design Technology on Thermal-Hydraulic Performance in Tight-Lattice Rod Bundles: II - Rod Bowing Effect on Boiling Transition under Transient Conditions

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Tamai, Hidesada; Kureta, Masatoshi; Ohnuki, Akira; Akimoto, Hajime

    A thermal-hydraulic feasibility project for an Innovative Water Reactor for Flexible fuel cycle (FLWR) has been performed since 2002. In this R&D project, large-scale thermal-hydraulic tests, several model experiments and development of advanced numerical analysis codes have been carried out. In this paper, we describe the critical power characteristics in a 37-rod tight-lattice bundle with rod bowing under transient states. It is observed that transient Boiling Transition (BT) always occurs axially at exit elevation of upper high-heat-flux region and transversely in the central area of the bundle, which is same as that under steady state. For the postulated power increase and flow decrease cases that may be possibly met in a normal operation of the FLWR, it is confirmed that no BT occurs when Initial Critical Power Ratio (ICPR) is 1.3. Moreover, when the transients are run under severer ICPR that causes BT, the transient critical powers are generally same as the steady ones. The experiments are analyzed with a modified TRAC-BFI code, where Japan Atomic Energy Agency (JAEA) newest critical power correlation is implemented for the BT judgement. The code shows good prediction for the occurrence or the non occurrence of the BT and predicts the BT starting time conservatively. Traditional quasi-steady state prediction of the transient BT is confirmed being applicable for the postulated abnormal transient processes in the tight-lattice bundle with rod bowing.

  18. Design of a tracer test experience and dynamic calibration of the hydraulic model for a full-scale wastewater treatment plant by use of AQUASIM.

    PubMed

    Fall, C; Loaiza-Navia, J L

    2007-08-01

    The setup of the hydraulic model structure of wastewater treatment plants (WWTPs) is an important step in the calibration of activated sludge models. The hydrodynamics of a full-scale municipal WWTP (Monterrey, Mexico) has been studied by means of the use of tracer tests and of a commercial simulator. A presimulation approach allowed the authors to quantify the appropriate rhodamine mass, set up a sampling plan, and evaluate the anticipated visual effect of the tracer test in the receiving river. The hydraulic behavior of the aeration tank for the first treatment line, a 7-cell plug-flow reactor, was shown to be best represented by 5 virtual mixed-tanks-in-series. The second treatment line, which included a vertical loop reactor (VLR), was best modeled as 3 tanks-in-series. The VLR, alone, was shown to be similar to a continuously stirred tank reactor, and not a circuit of tanks, as generally used to represent oxidation ditch reactors. PMID:17824536

  19. Control issues for a hydraulically powered dissimilar teleoperated system

    SciTech Connect

    Jansen, J.F.; Kress, R.L.

    1995-12-31

    This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schilling`s Titan II hydraulic manipulators are the slave manipulators and the master manipulators are from the Oak Ridge National Laboratory-developed Advanced Servo Manipulator.)

  20. Optimal design of high damping force engine mount featuring MR valve structure with both annular and radial flow paths

    NASA Astrophysics Data System (ADS)

    Nguyen, Q. H.; Choi, S. B.; Lee, Y. S.; Han, M. S.

    2013-11-01

    This paper focuses on the optimal design of a compact and high damping force engine mount featuring magnetorheological fluid (MRF). In the mount, a MR valve structure with both annular and radial flows is employed to generate a high damping force. First, the configuration and working principle of the proposed MR mount is introduced. The MRF flows in the mount are then analyzed and the governing equations of the MR mount are derived based on the Bingham plastic behavior of the MRF. An optimal design of the MR mount is then performed to find the optimal structure of the MR valve to generate a maximum damping force with certain design constraints. In addition, the gap size of MRF ducts is empirically chosen considering the ‘lockup’ problem of the mount at high frequency. Performance of the optimized MR mount is then evaluated based on finite element analysis and discussions on performance results of the optimized MR mount are given. The effectiveness of the proposed MR engine mount is demonstrated via computer simulation by presenting damping force and power consumption.

  1. A novel non-linear recursive filter design for extracting high rate pulse features in nuclear medicine imaging and spectroscopy.

    PubMed

    Sajedi, Salar; Kamal Asl, Alireza; Ay, Mohammad R; Farahani, Mohammad H; Rahmim, Arman

    2013-06-01

    Applications in imaging and spectroscopy rely on pulse processing methods for appropriate data generation. Often, the particular method utilized does not highly impact data quality, whereas in some scenarios, such as in the presence of high count rates or high frequency pulses, this issue merits extra consideration. In the present study, a new approach for pulse processing in nuclear medicine imaging and spectroscopy is introduced and evaluated. The new non-linear recursive filter (NLRF) performs nonlinear processing of the input signal and extracts the main pulse characteristics, having the powerful ability to recover pulses that would ordinarily result in pulse pile-up. The filter design defines sampling frequencies lower than the Nyquist frequency. In the literature, for systems involving NaI(Tl) detectors and photomultiplier tubes (PMTs), with a signal bandwidth considered as 15 MHz, the sampling frequency should be at least 30 MHz (the Nyquist rate), whereas in the present work, a sampling rate of 3.3 MHz was shown to yield very promising results. This was obtained by exploiting the known shape feature instead of utilizing a general sampling algorithm. The simulation and experimental results show that the proposed filter enhances count rates in spectroscopy. With this filter, the system behaves almost identically as a general pulse detection system with a dead time considerably reduced to the new sampling time (300 ns). Furthermore, because of its unique feature for determining exact event times, the method could prove very useful in time-of-flight PET imaging. PMID:22964063

  2. Design and features of the Acorn CorCap Cardiac Support Device: the concept of passive mechanical diastolic support.

    PubMed

    Walsh, Robert G

    2005-06-01

    The Laplace equation points to the importance of ventricular wall stress as a factor in heart failure development and progression. Based on animal and clinical experience with active and passive cardiomyoplasty, a synthetic passive constraint was proposed as a means of reducing excessive wall stress, and thus assuaging disease progression. The Acorn CorCap CSD Cardiac Support Device was designed to provide passive diastolic support and serve as a constraint against chronic cardiac dilation in heart failure. Basic and uncomplicated in appearance, the device nevertheless incorporates numerous sophisticated structural and functional features intended maximize therapeutic value. The device is fabricated from medical grade multifilament polyester yarn, in a specific knit construction chosen to provide structural integrity, low physical profile, pliability for intimate contact with the epicardial surface, ease of manipulation during implantation, and anisotropic compliance characteristics to encourage beneficial reverse remodeling. PMID:16258717

  3. The Identification, Implementation, and Evaluation of Critical User Interface Design Features of Computer-Assisted Instruction Programs in Mathematics for Students with Learning Disabilities

    ERIC Educational Resources Information Center

    Seo, You-Jin; Woo, Honguk

    2010-01-01

    Critical user interface design features of computer-assisted instruction programs in mathematics for students with learning disabilities and corresponding implementation guidelines were identified in this study. Based on the identified features and guidelines, a multimedia computer-assisted instruction program, "Math Explorer", which delivers…

  4. Optimization of hydraulic turbine diffuser

    NASA Astrophysics Data System (ADS)

    Moravec, Prokop; Hliník, Juraj; Rudolf, Pavel

    2016-03-01

    Hydraulic turbine diffuser recovers pressure energy from residual kinetic energy on turbine runner outlet. Efficiency of this process is especially important for high specific speed turbines, where almost 50% of available head is utilized within diffuser. Magnitude of the coefficient of pressure recovery can be significantly influenced by designing its proper shape. Present paper focuses on mathematical shape optimization method coupled with CFD. First method is based on direct search Nelder-Mead algorithm, while the second method employs adjoint solver and morphing. Results obtained with both methods are discussed and their advantages/disadvantages summarized.

  5. Hydraulic Extractor For Electronic Connectors

    NASA Technical Reports Server (NTRS)

    Smith, Larry D.

    1994-01-01

    Tool separates multipin electrical connectors in electronic equipment. Based on use of hydraulic pressure to apply balanced forces to connector and gently pull it free without damage. Easily assembled from readily available parts. Includes actuator syringe, two extractor syringes of disposable plastic 5-mL type, several pieces of flexible plastic tubing, and adjustable mounting components that brace tool in desired spacing configuration to suit connector extracted. Tubes and syringes filled with suitable fluid. Designed specifically for use on "D"-type connectors, also adapted for use wherever linear extraction motion used.

  6. High-precision hydraulic Stewart platform

    NASA Astrophysics Data System (ADS)

    van Silfhout, Roelof G.

    1999-08-01

    We present a novel design for a Stewart platform (or hexapod), an apparatus which performs positioning tasks with high accuracy. The platform, which is supported by six hydraulic telescopic struts, provides six degrees of freedom with 1 μm resolution. Rotations about user defined pivot points can be specified for any axis of rotation with microradian accuracy. Motion of the platform is performed by changing the strut lengths. Servo systems set and maintain the length of the struts to high precision using proportional hydraulic valves and incremental encoders. The combination of hydraulic actuators and a design which is optimized in terms of mechanical stiffness enables the platform to manipulate loads of up to 20 kN. Sophisticated software allows direct six-axis positioning including true path control. Our platform is an ideal support structure for a large variety of scientific instruments that require a stable alignment base with high-precision motion.

  7. Solid Waste Operations Complex (SWOC) Facilities Sprinkler System Hydraulic Calculations

    SciTech Connect

    KERSTEN, J.K.

    2003-07-11

    The attached calculations demonstrate sprinkler system operational water requirements as determined by hydraulic analysis. Hydraulic calculations for the waste storage buildings of the Central Waste Complex (CWC), T Plant, and Waste Receiving and Packaging (WRAP) facility are based upon flow testing performed by Fire Protection Engineers from the Hanford Fire Marshal's office. The calculations received peer review and approval prior to release. The hydraulic analysis program HASS Computer Program' (under license number 1609051210) is used to perform all analyses contained in this document. Hydraulic calculations demonstrate sprinkler system operability based upon each individual system design and available water supply under the most restrictive conditions.

  8. Applying Switched Reluctance Motor to Oil Hydraulic Pump Use

    NASA Astrophysics Data System (ADS)

    Yamai, Hiroyuki; Sawada, Yuzo; Ohyama, Kazunobu

    Hydraulic pump units are widely used to operate hydraulic actuators. In a typical machine shop, conventional constant speed hydraulic pump units consume more than 20% of the total electric power necessary to operate CNC machine tools. Most of that energy are wasted to run the axial piston pump at idle. This paper describes a variable speed hydraulic pump unit using a switched reluctance motor (SRM), which saves energy drastically. SRM was selected as the most suitable motor for this application. Design and control strategy of this motor are described. Application examples to machine tools shows the effectiveness of the new hybrid pump system in saving energy and in reducing acoustic noise.

  9. Wellness Partners: Design and Evaluation of a Web-Based Physical Activity Diary with Social Gaming Features for Adults

    PubMed Central

    Wang, Hua; Spruijt-Metz, Donna; Jordan-Marsh, Maryalice; Valente, Thomas William

    2013-01-01

    Background The United States is currently in an age of obesity and inactivity despite increasing public awareness and scientific knowledge of detrimental long-term health effects of this lifestyle. Behavior-tracking diaries offer an effective strategy for physical activity adherence and weight management. Furthermore, Web-based physical activity diaries can engage meaningful partners in people’s social networks through fun online gaming interactions and generate motivational mechanisms for effective behavioral change and positive health outcomes. Objective Wellness Partners (WP) is a Web-based intervention in the form of a physical activity diary with social networking and game features. Two versions were designed and developed for the purpose of this study—“Diary” only and “Diary+Game”. The objectives of this study included pilot testing the research process of this intervention design, implementation, evaluation, and exploring the effectiveness of social gaming features on adult participants’ physical activity and anthropometric measures. Methods We conducted a field experiment with randomized crossover design. Assessments occurred at baseline, first follow-up (FU, 5-8 weeks after using one version of WP), and second FU (5-8 weeks of using the other version of WP). In the control condition, participants started with the “Diary” version of WP while in the experimental condition, participants started with the “Diary+Game” version of WP. A total of 54 adults (egos) ages 44-88, and their family and friends (alters) ages 17-69 participated in the study in ego-network groups. Both egos and their alters completed online surveys about their exercise habits. In addition, egos completed anthropometric measurements of BMI, fat percentage, and fat mass by bioimpedance. Results From October 2009 to May 2010, flyers, emails, and Web advertisements yielded 335 volunteers who were screened. Rolling recruitment resulted in enrollment of 142 qualified

  10. Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography

    SciTech Connect

    Brauchler, R.; Doetsch, J.; Dietrich, P.; Sauter, M.

    2012-01-10

    In this study, hydraulic and seismic tomographic measurements were used to derive a site-specific relationship between the geophysical parameter p-wave velocity and the hydraulic parameters, diffusivity and specific storage. Our field study includes diffusivity tomograms derived from hydraulic travel time tomography, specific storage tomograms, derived from hydraulic attenuation tomography, and p-wave velocity tomograms, derived from seismic tomography. The tomographic inversion was performed in all three cases with the SIRT (Simultaneous Iterative Reconstruction Technique) algorithm, using a ray tracing technique with curved trajectories. The experimental set-up was designed such that the p-wave velocity tomogram overlaps the hydraulic tomograms by half. The experiments were performed at a wellcharacterized sand and gravel aquifer, located in the Leine River valley near Göttingen, Germany. Access to the shallow subsurface was provided by direct-push technology. The high spatial resolution of hydraulic and seismic tomography was exploited to derive representative site-specific relationships between the hydraulic and geophysical parameters, based on the area where geophysical and hydraulic tests were performed. The transformation of the p-wave velocities into hydraulic properties was undertaken using a k-means cluster analysis. Results demonstrate that the combination of hydraulic and geophysical tomographic data is a promising approach to improve hydrogeophysical site characterization.

  11. A novel Compton camera design featuring a rear-panel shield for substantial noise reduction in gamma-ray images

    NASA Astrophysics Data System (ADS)

    Nishiyama, T.; Kataoka, J.; Kishimoto, A.; Fujita, T.; Iwamoto, Y.; Taya, T.; Ohsuka, S.; Nakamura, S.; Hirayanagi, M.; Sakurai, N.; Adachi, S.; Uchiyama, T.

    2014-12-01

    After the Japanese nuclear disaster in 2011, large amounts of radioactive isotopes were released and still remain a serious problem in Japan. Consequently, various gamma cameras are being developed to help identify radiation hotspots and ensure effective decontamination operation. The Compton camera utilizes the kinematics of Compton scattering to contract images without using a mechanical collimator, and features a wide field of view. For instance, we have developed a novel Compton camera that features a small size (13 × 14 × 15 cm3) and light weight (1.9 kg), but which also achieves high sensitivity thanks to Ce:GAGG scintillators optically coupled wiith MPPC arrays. By definition, in such a Compton camera, gamma rays are expected to scatter in the ``scatterer'' and then be fully absorbed in the ``absorber'' (in what is called a forward-scattered event). However, high energy gamma rays often interact with the detector in the opposite direction - initially scattered in the absorber and then absorbed in the scatterer - in what is called a ``back-scattered'' event. Any contamination of such back-scattered events is known to substantially degrade the quality of gamma-ray images, but determining the order of gamma-ray interaction based solely on energy deposits in the scatterer and absorber is quite difficult. For this reason, we propose a novel yet simple Compton camera design that includes a rear-panel shield (a few mm thick) consisting of W or Pb located just behind the scatterer. Since the energy of scattered gamma rays in back-scattered events is much lower than that in forward-scattered events, we can effectively discriminate and reduce back-scattered events to improve the signal-to-noise ratio in the images. This paper presents our detailed optimization of the rear-panel shield using Geant4 simulation, and describes a demonstration test using our Compton camera.

  12. HYDRAULIC SERVO CONTROL MECHANISM

    DOEpatents

    Hussey, R.B.; Gottsche, M.J. Jr.

    1963-09-17

    A hydraulic servo control mechanism of compact construction and low fluid requirements is described. The mechanism consists of a main hydraulic piston, comprising the drive output, which is connected mechanically for feedback purposes to a servo control piston. A control sleeve having control slots for the system encloses the servo piston, which acts to cover or uncover the slots as a means of controlling the operation of the system. This operation permits only a small amount of fluid to regulate the operation of the mechanism, which, as a result, is compact and relatively light. This mechanism is particuiarly adaptable to the drive and control of control rods in nuclear reactors. (auth)

  13. Hydraulics of wells

    USGS Publications Warehouse

    McLaughlin, Thad G.

    1955-01-01

    Although the subject of this lecture is supposed to be concerned primarily with the hydraulics of wells, Professor Weers has asked that I also discuss the effects tat geological formations have on the quantity and quality of water available to wells. I will discuss the geology of Colorado in relation to the availability and quality of water with particular reference to the most productive aquifers or water-bearing formations in the State. I will then discuss the hydraulics of wells with the aim of emphasizing the differences between water-table and artesian conditions.

  14. Community perceptions of health insurance and their preferred design features: implications for the design of universal health coverage reforms in Kenya

    PubMed Central

    2013-01-01

    Background Health insurance is currently being considered as a mechanism for promoting progress to universal health coverage (UHC) in many African countries. The concept of health insurance is relatively new in Africa, it is hardly well understood and remains unclear how it will function in countries where the majority of the population work outside the formal sector. Kenya has been considering introducing a national health insurance scheme (NHIS) since 2004. Progress has been slow, but commitment to achieve UHC through a NHIS remains. This study contributes to this process by exploring communities’ understanding and perceptions of health insurance and their preferred designs features. Communities are the major beneficiaries of UHC reforms. Kenyans should understand the implications of health financing reforms and their preferred design features considered to ensure acceptability and sustainability. Methods Data presented in this paper are part of a study that explored feasibility of health insurance in Kenya. Data collection methods included a cross-sectional household survey (n = 594 households) and focus group discussions (n = 16). Results About half of the household survey respondents had at least one member in a health insurance scheme. There was high awareness of health insurance schemes but limited knowledge of how health insurance functions as well as understanding of key concepts related to income and risk cross-subsidization. Wide dissatisfaction with the public health system was reported. However, the government was the most preferred and trusted agency for collecting revenue as part of a NHIS. People preferred a comprehensive benefit package that included inpatient and outpatient care with no co-payments. Affordability of premiums, timing of contributions and the extent to which population needs would be met under a contributory scheme were major issues of concern for a NHIS design. Possibilities of funding health care through tax instead of

  15. KJRR-FAI Hydraulic Flow Testing Input Package

    SciTech Connect

    N.E. Woolstenhulme; R.B. Nielson; D.B. Chapman

    2013-12-01

    The INL, in cooperation with the KAERI via Cooperative Research And Development Agreement (CRADA), undertook an effort in the latter half of calendar year 2013 to produce a conceptual design for the KJRR-FAI campaign. The outcomes of this effort are documented in further detail elsewhere [5]. The KJRR-FAI was designed to be cooled by the ATR’s Primary Coolant System (PCS) with no provision for in-pile measurement or control of the hydraulic conditions in the irradiation assembly. The irradiation assembly was designed to achieve the target hydraulic conditions via engineered hydraulic losses in a throttling orifice at the outlet of the irradiation vehicle.

  16. Monitoring hydraulic fractures: state estimation using an extended Kalman filter

    NASA Astrophysics Data System (ADS)

    Alves Rochinha, Fernando; Peirce, Anthony

    2010-02-01

    There is considerable interest in using remote elastostatic deformations to identify the evolving geometry of underground fractures that are forced to propagate by the injection of high pressure viscous fluids. These so-called hydraulic fractures are used to increase the permeability in oil and gas reservoirs as well as to pre-fracture ore-bodies for enhanced mineral extraction. The undesirable intrusion of these hydraulic fractures into environmentally sensitive areas or into regions in mines which might pose safety hazards has stimulated the search for techniques to enable the evolving hydraulic fracture geometries to be monitored. Previous approaches to this problem have involved the inversion of the elastostatic data at isolated time steps in the time series provided by tiltmeter measurements of the displacement gradient field at selected points in the elastic medium. At each time step, parameters in simple static models of the fracture (e.g. a single displacement discontinuity) are identified. The approach adopted in this paper is not to regard the sequence of sampled elastostatic data as independent, but rather to treat the data as linked by the coupled elastic-lubrication equations that govern the propagation of the evolving hydraulic fracture. We combine the Extended Kalman Filter (EKF) with features of a recently developed implicit numerical scheme to solve the coupled free boundary problem in order to form a novel algorithm to identify the evolving fracture geometry. Numerical experiments demonstrate that, despite excluding significant physical processes in the forward numerical model, the EKF-numerical algorithm is able to compensate for the un-modeled dynamics by using the information fed back from tiltmeter data. Indeed the proposed algorithm is able to provide reasonably faithful estimates of the fracture geometry, which are shown to converge to the actual hydraulic fracture geometry as the number of tiltmeters is increased. Since the location of

  17. Nonelastomeric Rod Seals for Advanced Hydraulic Systems

    NASA Technical Reports Server (NTRS)

    Hady, W. F.; Waterman, A. W.

    1976-01-01

    Advanced high temperature hydraulic system rod sealing requirements can be met by using seals made of nonelastomeric (plastic) materials in applications where elastomers do not have adequate life. Exploratory seal designs were optimized for advanced applications using machinable polyimide materials. These seals demonstrated equivalent flight hour lives of 12,500 at 350 F and 9,875 at 400 F in advanced hydraulic system simulation. Successful operation was also attained under simulated space shuttle applications; 96 reentry thermal cycles and 1,438 hours of vacuum storage. Tests of less expensive molded plastic seals indicated a need for improved materials to provide equivalent performance to the machined seals.

  18. Computational design of organometallic oligomers featuring 1,3-metal-carbon bonding and planar tetracoordinate carbon atoms.

    PubMed

    Zhao, Xue-Feng; Yuan, Cai-Xia; Wang, Xiang; Li, Jia-Jia; Wu, Yan-Bo; Wang, Xiaotai

    2016-01-15

    Density functional theory computations (B3LYP) have been used to explore the chemistry of titanium-aromatic carbon "edge complexes" with 1,3-metal-carbon (1,3-MC) bonding between Ti and planar tetracoordinate Cβ . The titanium-coordinated, end-capping chlorides are replaced with OH or SH groups to afford two series of difunctional monomers that can undergo condensation to form oxide- and sulfide-bridged oligomers. The sulfide-linked oligomers have less molecular strain and are more exergonic than the corresponding oxide-linked oligomers. The HOMO-LUMO gap of the oligomers varies with their composition and decreases with growing oligomer chain. This theoretical study is intended to enrich 1,3-MC bonding and planar tetracoordinate carbon chemistry and provide interesting ideas to experimentalists. Organometallic complexes with the TiE2 (E = OH and SH) decoration on the edge of aromatic hydrocarbons have been computationally designed, which feature 1,3-metal-carbon (1,3-MC) bonding between titanium and planar tetracoordinate β-carbon. Condensation of these difunctional monomers by eliminating small molecules (H2O and H2S) produce chain-like oligomers. The HOMO-LUMO gaps of the oligomers decreases with growing oligomer chain, a trend that suggests possible semiconductor properties for oligomers with longer chains. PMID:26399226

  19. Integrating valve-inspired design features into poly(ethylene glycol) hydrogel scaffolds for heart valve tissue engineering.

    PubMed

    Zhang, Xing; Xu, Bin; Puperi, Daniel S; Yonezawa, Aline L; Wu, Yan; Tseng, Hubert; Cuchiara, Maude L; West, Jennifer L; Grande-Allen, K Jane

    2015-03-01

    The development of advanced scaffolds that recapitulate the anisotropic mechanical behavior and biological functions of the extracellular matrix in leaflets would be transformative for heart valve tissue engineering. In this study, anisotropic mechanical properties were established in poly(ethylene glycol) (PEG) hydrogels by crosslinking stripes of 3.4 kDa PEG diacrylate (PEGDA) within 20 kDa PEGDA base hydrogels using a photolithographic patterning method. Varying the stripe width and spacing resulted in a tensile elastic modulus parallel to the stripes that was 4.1-6.8 times greater than that in the perpendicular direction, comparable to the degree of anisotropy between the circumferential and radial orientations in native valve leaflets. Biomimetic PEG-peptide hydrogels were prepared by tethering the cell-adhesive peptide RGDS and incorporating the collagenase-degradable peptide PQ (GGGPQG↓IWGQGK) into the polymer network. The specific amounts of RGDS and PEG-PQ within the resulting hydrogels influenced the elongation, de novo extracellular matrix deposition and hydrogel degradation behavior of encapsulated valvular interstitial cells (VICs). In addition, the morphology and activation of VICs grown atop PEG hydrogels could be modulated by controlling the concentration or micro-patterning profile of PEG-RGDS. These results are promising for the fabrication of PEG-based hydrogels using anatomically and biologically inspired scaffold design features for heart valve tissue engineering. PMID:25433168

  20. Small hydraulic turbine drives

    NASA Technical Reports Server (NTRS)

    Rostafinski, W. A.

    1970-01-01

    Turbine, driven by the fluid being pumped, requires no external controls, is completely integrated into the flow system, and has bearings which utilize the main fluid for lubrication and cooling. Torque capabilities compare favorably with those developed by positive displacement hydraulic motors.

  1. Hydraulic Shutdown Monitor

    NASA Technical Reports Server (NTRS)

    Fleming, S. T.; Harrington, D. B.

    1986-01-01

    Adding switch allows inappropriate control actions to be overridden. Four-pole, double-throw switch added to front panel of controller to disable tracking-error and endpoint-error circuitry yet still retain overload-detection capability. Previously, it was necessary to use adjustable-voltage-level detection equipment connected with cables to hydraulic "dump" or shutdown circuitry in controller.

  2. Integration in Hydraulics.

    ERIC Educational Resources Information Center

    Sworder, Steven C.

    This paper presents an application of integration to the field of hydraulics. An integral relation for the time required to drop the fluid contained in a cylindrical tank from one level to another using a hole in the tank wall is derived. Procedures for constructing the experimental equipment and procedures for determining the coefficient of…

  3. Microbial effect on soil hydraulic properties

    NASA Astrophysics Data System (ADS)

    Furman, Alex; Rosenzweig, Ravid; Volk, Elazar; Rosenkranz, Hella; Iden, Sascha; Durner, Wolfgang

    2014-05-01

    Although largely ignored, the soil contains large amount of biofilms (attached microbes) that can affect many processes. While biochemical processes are studied, biophysical processes receive only little attention. Biofilms may occupy some of the pore space, and by that affect the soil hydraulic properties. This effect on unsaturated soils, however, was not intensively studied. In this research we directly measure the hydraulic properties, namely the soil's unsaturated hydraulic conductivity function and retention curve, for soils containing real biofilm. To do that we inoculate soil with biofilm-forming bacteria and incubate it with sufficient amounts of nutrient until biofilm is formed. The hydraulic properties of the incubated soil are then measured using several techniques, including multi-step outflow and evaporation method. The longer measurements (evaporation method) are conducted under refrigeration conditions to minimize microbial activity during the experiment. The results show a clear effect of the biofilm, where the biofilm-affected soil (sandy loam in our case) behaves like a much finer soil. This qualitatively makes sense as the biofilm generates an effective pore size distribution that is characterized by smaller pores. However, the effect is much more complex and needs to be studied carefully considering (for example) dual porosity models. We compare our preliminary results with other experiments, including flow-through column experiments and experiments with biofilm analogues. Clearly a better understanding of the way microbial activity alters the hydraulic properties may help designing more efficient bioremediation, irrigation, and other soil-related processes.

  4. Hydraulic catworks system

    SciTech Connect

    Walker, J.L.

    1981-03-03

    A hydraulic catworks system is described for use on a well drilling rig for making up and breaking out a drill string which includes a hydraulic makeup piston and cylinder assembly for actuating a makeup line connected to the makeup tongs, and a breakout piston and cylinder assembly connected to a breakout line for actuating the breakout tongs. A makeup hydraulic control valve controls hydraulic fluid to first and second lines connected to the makeup assembly with the first line connected for extending the makeup line and the second line connected for retracting the makeup line. A breakout hydraulic control valve controls fluid to third and fourth lines with the third line connected for extending the breakout line and the fourth line connected for retracting the breakout line. Manual air control means are provided for selectively actuating the makeup and breakout control valves. A variable pressure control is connected to the second line for controlling the makeup torque. Preferably, the makeup and breakout assemblies are vertically connected to the legs of the drilling rig and rollers are positioned horizontally with the makeup and breakout tongs and connected to the breakout and makeup lines. Preferably, a sheave is connected to the makeup assembly and the makeup line passes over the sheave with its free end fixedly secured. A re-generative system is provided on the makeup assembly for increasing the speed of the makeup line extension. Preferably the makeup and breakout cylinders are of the same cross-sectional area with the stroke of the breakout cylinder being less than the stroke of the makeup cylinder.

  5. AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT IX, AUTOMATIC TRANSMISSIONS--HYDRAULIC SYSTEM (PART I).

    ERIC Educational Resources Information Center

    Human Engineering Inst., Cleveland, OH.

    THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OIL FLOW WITHIN HYDRAULIC TRANSMISSIONS USED ON DIESEL POWERED VEHICLES. TOPICS ARE GENERAL DESCRIPTION, HYDRAULIC CIRCUITS, AND BRAKE HYDRAULIC CIRCUIT AND OPERATION. THE MODULE CONSISTS OF A SELF-INSTRUCTIONAL PROGRAMED TRAINING FILM "LEARNING ABOUT THE ALLISON…

  6. Testing Map Features Designed to Convey the Uncertainty of Cancer Risk: Insights Gained From Assessing Judgments of Information Adequacy and Communication Goals

    PubMed Central

    Severtson, Dolores J.

    2015-01-01

    Barriers to communicating the uncertainty of environmental health risks include preferences for certain information and low numeracy. Map features designed to communicate the magnitude and uncertainty of estimated cancer risk from air pollution were tested among 826 participants to assess how map features influenced judgments of adequacy and the intended communication goals. An uncertain versus certain visual feature was judged as less adequate but met both communication goals and addressed numeracy barriers. Expressing relative risk using words communicated uncertainty and addressed numeracy barriers but was judged as highly inadequate. Risk communication and visual cognition concepts were applied to explain findings. PMID:26412960

  7. Performances of a balanced hydraulic motor with planetary gear train

    NASA Astrophysics Data System (ADS)

    Yu, Hongying; Luo, Changjie; Wang, Huimin

    2012-07-01

    The current research of a balanced hydraulic motor focuses on the characteristics of the motor with three planet gears. References of a balanced hydraulic motor with more than three planet gears are hardly found. In order to study the characteristics of a balanced hydraulic motor with planetary gear train that includes more than three planet gears, on the basis of analysis of the structure and working principle of a balanced hydraulic motor with planetary gear train, formulas are deduced for calculating the hydraulic motor's primary performance indexes such as displacement, unit volume displacement, flowrate fluctuation ratio, etc. Influences of the gears' tooth number on displacement and flowrate characteristics are analyzed. In order to guarantee the reliability of sealing capability, the necessary conditions that tooth number of the sun gear and the planet gears should satisfy are discussed. Selecting large unit volume displacement and small displacement fluctuation ratio as designing objectives, a balanced hydraulic motor with three planet gears and a common gear motor are designed under the conditions of same displacement, tooth addendum coefficien and clearance coefficient. By comparing the unit volume displacement and fluctuation ratio of the two motors, it can be seen that the balanced hydraulic motor with planetary gear train has the advantages of smaller fluctuation ratio and larger unit volume displacement. The results provide theoretical basis for choosing gear tooth-number of this kind of hydraulic motor.

  8. Operationally efficient propulsion system study (OEPSS) data book. Volume 7; Launch Operations Index (LOI) Design Features and Options

    NASA Technical Reports Server (NTRS)

    Ziese, James M.

    1992-01-01

    A design tool of figure of merit was developed that allows the operability of a propulsion system design to be measured. This Launch Operations Index (LOI) relates Operations Efficiency to System Complexity. The figure of Merit can be used by conceptual designers to compare different propulsion system designs based on their impact on launch operations. The LOI will improve the design process by making sure direct launch operations experience is a necessary feedback to the design process.

  9. Mechanics of Hydraulic Fractures

    NASA Astrophysics Data System (ADS)

    Detournay, Emmanuel

    2016-01-01

    Hydraulic fractures represent a particular class of tensile fractures that propagate in solid media under pre-existing compressive stresses as a result of internal pressurization by an injected viscous fluid. The main application of engineered hydraulic fractures is the stimulation of oil and gas wells to increase production. Several physical processes affect the propagation of these fractures, including the flow of viscous fluid, creation of solid surfaces, and leak-off of fracturing fluid. The interplay and the competition between these processes lead to multiple length scales and timescales in the system, which reveal the shifting influence of the far-field stress, viscous dissipation, fracture energy, and leak-off as the fracture propagates.

  10. Remotely Adjustable Hydraulic Pump

    NASA Technical Reports Server (NTRS)

    Kouns, H. H.; Gardner, L. D.

    1987-01-01

    Outlet pressure adjusted to match varying loads. Electrohydraulic servo has positioned sleeve in leftmost position, adjusting outlet pressure to maximum value. Sleeve in equilibrium position, with control land covering control port. For lowest pressure setting, sleeve shifted toward right by increased pressure on sleeve shoulder from servovalve. Pump used in aircraft and robots, where hydraulic actuators repeatedly turned on and off, changing pump load frequently and over wide range.

  11. Rapid field application of hydraulic tomography

    NASA Astrophysics Data System (ADS)

    Brauchler, R.; Hu, R.; Hu, L.; Parras, S. J.; Bayer, P.; Dietrich, P.; Ptak, T.

    2013-12-01

    The motivation of this field study is the need for investigation methods that are both rapid and well suited for resolving the spatial distribution of hydraulic properties in aquifers. Therefore, we propose a field strategy for hydraulic tomography that can be analyzed and performed with a similar speed as direct-push profiling. The field implementation is designed in a way that a suite of tomographic measurements can be recorded in one day. We utilize direct-push technology for the well installation and limit the pumping time to 300 s, which permits us to record 30 transient pressure response curves between two wells in one working day. For the inversion, we applied a computationally efficient inversion scheme which is based on the transformation of the ground water flow equation into a form of the eikonal equation. By exploiting the early part of a transient hydraulic pressure response recorded during cross-well tests only short-term pumping tests are required. The main advantages of the inversion scheme are the low computational requirements of eikonal solvers and that no information about the hydraulic boundaries is needed. The short pumping time in combination with the straightforward inversion technique allows for the reconstruction of hydraulic conductivity and specific storage distributions already in the field, which is particularly useful for an adaptive site investigation approach. Additionally, direct-push injection logging is performed at the field site, and the obtained field data is utilized for successful validation of the hydraulic tomograms. We also compare both methods with respect to the necessary requirements, time demand in the field and complexity of interpretation.

  12. [Effect of water depths on hydraulic performance of pond wetlands].

    PubMed

    Guo, Chang-Qiang; Dong, Bin; Liu, Jun-Jie; Liu, Chun-Guo; Feng, Da-Peng; Liu, Fang-Ping

    2014-11-01

    Pond wetlands have been widely used in the treatment of drainage water from paddy fields. However, wetland hydraulic performance and purification effects are affected by many factors, such as water depth, flow rate, aspect ratio and vegetation distribution, and the better understanding of these factors would be helpful to improve the quality of wetland design, operation and management. This paper analyzed the effect of three different water depths (20, 40 and 60 cm) on the hydraulic performance of pond wetland through the dye tracer experiments with Rhodamine WT. The hydraulic indices, i. e., effective volume ratio, nominal serial complete mixing tanks (N), hydraulic efficiency (λ), were selected for analysis through the hydraulic residence time distribution (RTD) curve. The results showed that the effective volume rate rose from 0.421 to 0.844 and the hydraulic efficiency from 0.281 to 0.604 when the water depth declined from 60 cm to 20 cm. This indicated that the wetland hydraulic performance improved as the water depth decreased. In addition, the hydraulic performance of the first half of the wetland was significantly better than that of the second half. The flow regime of the first half approached complete mixing because of the mixing index (N) approaching 1 and its effective volume rate was above 0.9 when the water depth was relatively low (20 and 40 cm). The normalized RTD curves demonstrated a good agreement between moment analysis parameters and hydraulic parameters, and a great consistency between the hydraulic parameters and moment index which was not affected by tail truncation error. The experimental study concluded that a lower water depth was favorable to improve the hydraulic performance of pond wetlands. PMID:25898628

  13. Analytical Modeling of Shale Hydraulic Fracturing and Gas Production

    NASA Astrophysics Data System (ADS)

    Xu, W.

    2012-12-01

    Shale gas is abundant all over the world. Due to its extremely low permeability, extensive stimulation of a shale reservoir is always required for its economic production. Hydraulic fracturing has been the primary method of shale reservoir stimulation. Consequently the design and optimization of a hydraulic fracturing treatment plays a vital role insuring job success and economic production. Due to the many variables involved and the lack of a simple yet robust tool based on fundamental physics, horizontal well placement and fracturing job designs have to certain degree been a guessing game built on previous trial and error experience. This paper presents a method for hydraulic fracturing design and optimization in these environments. The growth of a complex hydraulic fracture network (HFN) during a fracturing job is equivalently represented by a wiremesh fracturing model (WFM) constructed on the basis of fracture mechanics and mass balance. The model also simulates proppant transport and placement during HFN growth. Results of WFM simulations can then be used as the input into a wiremesh production model (WPM) constructed based on WFM. WPM represents gas flow through the wiremesh HFN by an elliptic flow and the flow of gas in shale matrix by a novel analytical solution accounting for contributions from both free and adsorbed gases stored in the pore space. WPM simulation is validated by testing against numerical simulations using a commercially available reservoir production simulator. Due to the analytical nature of WFM and WPM, both hydraulic fracturing and gas production simulations run very fast on a regular personal computer and are suitable for hydraulic fracturing job design and optimization. A case study is presented to demonstrate how a non-optimized hydraulic fracturing job might have been optimized using WFM and WPM simulations.Fig. 1. Ellipsoidal representation of (a) stimulated reservoir and (b) hydraulic fracture network created by hydraulic

  14. The Effects of State Policy Design Features on Take-Up and Crowd-Out Rates for the Sate Children's Health Insurance Program

    ERIC Educational Resources Information Center

    Bansak, Cynthia; Raphael, Steven

    2007-01-01

    We evaluate the effects of state policy design features on SCHIP take-up rates and on the degree to which SCHIP benefits crowd out private benefits. The results indicate overall program take-up rates of approximately 10 percent. However, there is considerable heterogeneity across states, suggesting a potential role of inter-state variation in…

  15. Vehicle hydraulic cooling fan system

    SciTech Connect

    Nilson, C.A.

    1993-06-08

    A hydraulic cooling system for vehicles having an internal combustion engine cooled by a radiator and a coolant is described, comprising, in combination, a shroud adapted to be mounted adjacent the radiator having a wall forming an air passage and defining a first port disposed adjacent the radiator and a second port spaced from the first port, a fan located within the second port, a hydraulic fan motor operatively connected to the fan, a hydraulic pump operatively connected to the engine for producing a pressurized hydraulic fluid flow, a hydraulic circuit interconnecting the pump to the fan motor, the circuit including a control valve, a hydraulic fluid reservoir and a heat exchanger, the heat exchanger being mounted within the shroud air passage.

  16. Limits of downstream hydraulic geometry

    NASA Astrophysics Data System (ADS)

    Wohl, Ellen

    2004-10-01

    Adjustments to flow width, depth, and velocity in response to changes in discharge are commonly characterized by using downstream hydraulic geometry relationships. The spatial limits of these relationships within a drainage basin have not been systematically quantified. Where the erosional resistance of the channel substrate is sufficiently large, hydraulic driving forces presumably will be unable to adjust channel form. Data sets from 10 mountain rivers in the United States, Panama, Nepal, and New Zealand are used in this study to explore the limits of downstream hydraulic geometry relationships. Where the ratio of stream power to sediment size (Ω/D84) exceeds 10,000 kg/s3, downstream hydraulic geometry is well developed; where the ratio falls below 10,000 kg/s3, downstream hydraulic geometry relationships are poorly developed. These limitations on downstream hydraulic geometry have important implications for channel engineering and simulations of landscape change.

  17. Hydraulic mining method

    DOEpatents

    Huffman, Lester H.; Knoke, Gerald S.

    1985-08-20

    A method of hydraulically mining an underground pitched mineral vein comprising drilling a vertical borehole through the earth's lithosphere into the vein and drilling a slant borehole along the footwall of the vein to intersect the vertical borehole. Material is removed from the mineral vein by directing a high pressure water jet thereagainst. The resulting slurry of mineral fragments and water flows along the slant borehole into the lower end of the vertical borehole from where it is pumped upwardly through the vertical borehole to the surface.

  18. Research of performance prediction to energy on hydraulic turbine

    NASA Astrophysics Data System (ADS)

    Quan, H.; Li, R. N.; Li, Q. F.; Han, W.; Su, Q. M.

    2012-11-01

    Refer to the low specific speed Francis turbine blade design principle and double-suction pump structure. Then, design a horizontal double-channel hydraulic turbine Francis. Through adding different guide vane airfoil and and no guide vane airfoil on the hydraulic conductivity components to predict hydraulic turbine energy and using Fluent software to numerical simulation that the operating conditions and point. The results show that the blade pressure surface and suction surface pressure is low when the hydraulic turbine installation is added standard positive curvature of the guide vane and modified positive curvature of guide vane. Therefore, the efficiency of energy recovery is low. However, the pressure of negative curvature guide vane and symmetric guide vane added on hydraulic turbine installations is larger than that of the former ones, and it is conducive to working of runner. With the decreasing of guide vane opening, increasing of inlet angle, flow state gets significantly worse. Then, others obvious phenomena are that the reflux and horizontal flow appeared in blade pressure surface. At the same time, the vortex was formed in Leaf Road, leading to the loss of energy. Through analyzing the distribution of pressure, velocity, flow lines of over-current flow in the the back hydraulic conductivity components in above programs we can known that the hydraulic turbine installation added guide vane is more reasonable than without guide vanes, it is conducive to improve efficiency of energy conversion.

  19. Computational open-channel hydraulics for movable-bed problems

    USGS Publications Warehouse

    Lai, Chintu

    1990-01-01

    As a major branch of computational hydraulics, notable advances have been made in numerical modeling of unsteady open-channel flow since the beginning of the computer age. According to the broader definition and scope of 'computational hydraulics,' the basic concepts and technology of modeling unsteady open-channel flow have been systematically studied previously. As a natural extension, computational open-channel hydraulics for movable-bed problems are addressed in this paper. The introduction of the multimode method of characteristics (MMOC) has made the modeling of this class of unsteady flows both practical and effective. New modeling techniques are developed, thereby shedding light on several aspects of computational hydraulics. Some special features of movable-bed channel-flow simulation are discussed here in the same order as given by the author in the fixed-bed case.

  20. New parameters influencing hydraulic runner lifetime

    NASA Astrophysics Data System (ADS)

    Sabourin, M.; Thibault, D.; Bouffard, D. A.; Lévesque, M.

    2010-08-01

    Traditionally, hydraulic runner mechanical design is based on calculation of static stresses. Today, validation of hydraulic runner design in terms of reliability requires taking into account the fatigue effect of dynamics loads. A damage tolerant approach based on fracture mechanics is the method chosen by Alstom and Hydro-Québec to study fatigue damage in runners. This requires a careful examination of all factors influencing material fatigue behavior. Such material behavior depends mainly on the chemical composition, microstructure and thermal history of the component, and on the resulting residual stresses. Measurement of fracture mechanics properties of various steels have demonstrated that runner lifetime can be significantly altered by differences in the manufacturing process, although remaining in accordance with agreed practices and standards such as ASTM. Carbon content and heat treatment are suspected to influence fatigue lifetime. This will have to be investigated by continuing the current research.

  1. Understanding the Ways in Which Design Features of Educational Websites Impact upon Student Learning Outcomes in Blended Learning Environments

    ERIC Educational Resources Information Center

    Kember, David; McNaught, Carmel; Chong, Fanny C. Y.; Lam, Paul; Cheng, K. F.

    2010-01-01

    This study investigated the effectiveness, in terms of the attainment of relevant learning outcomes, of the types of learning promoted by educational features commonly incorporated in course management systems. Twenty-one courses with significant use of the Internet, but with face-to-face teaching as the predominant instructional mode, were…

  2. Influence of Rock Fabric on Hydraulic Fracture Propagation: Laboratory Study

    NASA Astrophysics Data System (ADS)

    Stanchits, S. A.; Desroches, J.; Burghardt, J.; Surdi, A.; Whitney, N.

    2014-12-01

    Massive hydraulic fracturing is required for commercial gas production from unconventional reservoirs. These reservoirs are often highly fractured and heterogeneous, which may cause significant fracture complexity and also arrest propagation of hydraulic fractures, leading to production decrease. One of the goals of our study was to investigate the influence of rock fabric features on near-wellbore fracture geometry and complexity. We performed a series of laboratory tests on Niobrara outcrop shale blocks with dimensions of 30 x 30 x 36 inches in a true-triaxial loading frame. Acoustic Emission (AE) technique was applied to monitor hydraulic fracture initiation and dynamics of fracture propagation. After the tests, the shape of the created hydraulic fracture was mapped by goniometry technique. To estimate fracture aperture, particles of different sizes were injected with fracturing fluid. In all tests, AE analysis indicated hydraulic fracture initiation prior to breakdown or the maximum of wellbore pressure. In most tests, AE analysis revealed asymmetrical hydraulic fracture shapes. Post-test analysis demonstrated good correspondence of AE results with the actual 3D shape of the fracture surface map. AE analysis confirmed that in some of these tests, the hydraulic fracture approached one face of the block before the maximum wellbore pressure had been reached. We have found that in such cases the propagation of hydraulic fracture in the opposite direction was arrested by the presence of mineralized interfaces. Mapping the distribution of injected particles confirmed the creation of a narrow-width aperture in the vicinity of pre-existing interfaces, restricting fracture conductivity. Based on the results of our study, we concluded that the presence of planes of weakness, such as mineralized natural fractures, can result in the arrest of hydraulic fracture propagation, or in poor fracture geometries with limited aperture, that in turn could lead to high net pressure

  3. 110. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    110. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL PANEL IN UMBILICAL MAST PUMP ROOM (109), LSB (BLDG. 770) ACCUMULATOR FOR MAST RETRACTION ON LEFT. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  4. 128. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    128. TUBING FOR HYDRAULIC FLUID AT BACK OF HYDRAULIC CONTROL PANEL IN UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751). PUMP ON RIGHT; ACCUMULATOR FOR MAST RETRACTION ON LEFT. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  5. Personalized Integrated Educational System (PIES) for the Learner-Centered Information-Age Paradigm of Education: A Study to Improve the Design of the Functions and Features of PIES

    ERIC Educational Resources Information Center

    Dutta, Pratima

    2013-01-01

    The Personalized Integrated Educational System (PIES) design theory is a design recommendation regarding the function and features of Learning Managements Systems (LMS) that can support the information-age learner-centered paradigm of education. The purpose of this study was to improve the proposed functions and features of the PIES design theory…

  6. Concepts, features, and design of a sixteen-to-four beam combiner for ILSE (Induction Linac Systems Experiment)

    SciTech Connect

    Judd, D.L.; Celata, C.; Close, E.; Faltens, A.; Hahn, K.; La Mon, K.; Lee, E.P.; Smith, L.; Thur, W.

    1989-03-01

    Sixteen intense parallel ion beams are to be transversely combined into four by dispersionless double bends. Emittance growth due to electrostatic energy redistribution and to the geometry is evaluated. Most bending elements are electric, and alternate with AG electrostatic quadrupoles similar to those upstream. The final elements are magnetic, combining focusing and ''unbending''. Electrode shapes and pulsed-current arrays (having very small clearances), and mechanical and electric features of the combiner, and described. 1 ref., 7 figs.

  7. Tractor Hydraulics. A Teaching Reference.

    ERIC Educational Resources Information Center

    American Association for Vocational Instructional Materials, Athens, GA.

    The manual was developed to help provide a better understanding of how and why hydraulic principles serve the purposes of weight reduction, increase of physical effort, and more precise control to machines of all types. The four components that are necessary to have a workable hydraulic system--a reservoir, a pump, a valve, and a motor (cylinder)…

  8. Hydraulics. FOS: Fundamentals of Service.

    ERIC Educational Resources Information Center

    John Deere Co., Moline, IL.

    This manual on hydraulics is one of a series of power mechanics texts and visual aids for training in the servicing of agricultural and industrial machinery. Focus is on oil hydraulics. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and laymen. The twelve chapters focus…

  9. Overview of microseismic monitoring of hydraulic fracturing for unconventional oil and gas plays

    NASA Astrophysics Data System (ADS)

    Shemeta, J. E.

    2011-12-01

    The exponential growth of unconventional resources for oil and gas production has been driven by the use of horizontal drilling and hydraulic fracturing. These drilling and completion methods increase the contact area of the low permeability and porosity hydrocarbon bearing formations and allow for economic production in what was previously considered uncommercial rock. These new resource plays have sparked an enormous interest in microseismic monitoring of hydraulic fracture treatments. As a hydraulic fracture is pumped, microseismic events are emitted in a volume of rock surrounding the stimulated fracture. The goal of the monitoring is to identify and locate the microseismic events to a high degree of precision and to map the position of the induced hydraulic fracture in time and space. The microseismic events are very small, typically having a moment-magnitude range of -4 to 0. The microseismic data are collected using a variety of seismic array designs and instrumentation, including borehole, shallow borehole, near-surface and surface arrays, using either of three-component clamped 15 Hz borehole sondes to simple vertical 10 Hz geophones for surface monitoring. The collection and processing of these data is currently under rapid technical development. Each monitoring method has technical challenges which include accurate velocity modeling, correct seismic phase identification and signal to noise issues. The microseismic locations are used to guide hydrocarbon exploration and production companies in crucial reservoir development decisions such as the direction to drill the horizontal well bores and the appropriate inter-well spacing between horizontal wells to optimally drain the resource. The fracture mapping is also used to guide fracture and reservoir engineers in designing and calibrating the fluid volumes and types, injection rates and pressures for the hydraulic fracture treatments. The microseismic data can be located and mapped in near real-time during

  10. Hydraulically actuated well shifting tool

    SciTech Connect

    Roth, B.A.

    1992-10-20

    This patent describes a hydraulically actuated shifting tool for actuating a sliding member in a well tool. It comprises: a housing having a hydraulic fluid bore therein; shifting dog means positioned on the housing for movement away and toward the housing; locking dog means positioned on the housing for movement away and toward the body; shifting dog hydraulic actuating means in fluid communication with the bore for causing engagement of the shifting dogs with the sliding member; locking dog hydraulic actuating means in communication with the bore for causing engagement of the locking dogs with the locking means; and hydraulic shifting means in communication with the bore for causing relative movement between the shifting dog means and the locking dog means for shifting the sliding sleeve.

  11. Percolation Theory and Modern Hydraulic Fracturing

    NASA Astrophysics Data System (ADS)

    Norris, J. Q.; Turcotte, D. L.; Rundle, J. B.

    2015-12-01

    During the past few years, we have been developing a percolation model for fracking. This model provides a powerful tool for understanding the growth and properties of the complex fracture networks generated during a modern high volume hydraulic fracture stimulations of tight shale reservoirs. The model can also be used to understand the interaction between the growing fracture network and natural reservoir features such as joint sets and faults. Additionally, the model produces a power-law distribution of bursts which can easily be compared to observed microseismicity.

  12. Hydraulic Fracturing and the Environment

    NASA Astrophysics Data System (ADS)

    Ayatollahy Tafti, T.; Aminzadeh, F.; Jafarpour, B.; de Barros, F.

    2013-12-01

    In this presentation, we highlight two key environmental concerns of hydraulic fracturing (HF), namely induced seismicity and groundwater contamination (GC). We examine the induced seismicity (IS) associated with different subsurface fluid injection and production (SFIP) operations and the key operational parameters of SFIP impacting it. In addition we review the key potential sources for possible water contamination. Both in the case of IS and GC we propose modeling and data analysis methods to quantify the risk factors to be used for monitoring and risk reduction. SFIP include presents a risk in hydraulic fracturing, waste water injection, enhanced oil recovery as well as geothermal energy operations. Although a recent report (NRC 2012) documents that HF is not responsible for most of the induced seismicities, we primarily focus on HF here. We look into vaious operational parameters such as volume and rate of water injection, the direction of the well versus the natural fracture network, the depth of the target and the local stress field and fault system, as well as other geological features. The latter would determine the potential for triggering tectonic related events by small induced seismicity events. We provide the building blocks for IS risk assessment and monitoring. The system we propose will involve adequate layers of complexity based on mapped seismic attributes as well as results from ANN and probabilistic predictive modeling workflows. This leads to a set of guidelines which further defines 'safe operating conditions' and 'safe operating zones' which will be a valuable reference for future SFIP operations. We also illustrate how HF can lead to groundwater aquifer contamination. The source of aquifer contamination can be the hydrocarbon gas or the chemicals used in the injected liquid in the formation. We explore possible pathways of contamination within and discuss the likelihood of contamination from each source. Many of the chemical compounds used

  13. Piezoelectric-hydraulic pump based band brake actuation system for automotive transmission control

    NASA Astrophysics Data System (ADS)

    Kim, Gi-Woo; Wang, K. W.

    2007-04-01

    The actuation system of friction elements (such as band brakes) is essential for high quality operations in modern automotive automatic transmissions (in short, ATs). The current band brake actuation system consists of several hydraulic components, including the oil pump, the regulating valve and the control valves. In general, it has been recognized that the current AT band brake actuation system has many limitations. For example, the oil pump and valve body are relatively heavy and complex. Also, the oil pumps induce inherently large drag torque, which affects fuel economy. This research is to overcome these problems of the current system by exploring the utilization of a hybrid type piezo-hydraulic pump device for AT band brake control. This new actuating system integrates a piezo-hydraulic pump to the input of the band brake. Compared with the current systems, this new actuator features much simpler structure, smaller size, and lower weight. This paper describes the development, design and fabrication of the new stand-alone prototype actuator for AT band brake control. An analytical model is developed and validated using experimental data. Performance tests on the hardware and system simulations utilizing the validated model are performed to characterize the new prototype actuator. It is predicted that with increasing of accumulator pressure and driving frequency, the proposed prototype actuating system will satisfy the band brake requirement for AT shift control.

  14. Amazon flood wave hydraulics

    NASA Astrophysics Data System (ADS)

    Trigg, Mark A.; Wilson, Matthew D.; Bates, Paul D.; Horritt, Matthew S.; Alsdorf, Douglas E.; Forsberg, Bruce R.; Vega, Maria C.

    2009-07-01

    SummaryA bathymetric survey of 575 km of the central Amazon River and one of its tributaries, the Purus, are combined with gauged data to characterise the Amazon flood wave, and for hydraulic modelling of the main channel for the period June 1995-March 1997 with the LISFLOOD-FP and HEC-RAS hydraulic models. Our investigations show that the Amazon flood wave is subcritical and diffusive in character and, due to shallow bed slopes, backwater conditions control significant reach lengths and are present for low and high water states. Comparison of the different models shows that it is necessary to include at least the diffusion term in any model, and the RMSE error in predicted water elevation at all cross sections introduced by ignoring the acceleration and advection terms is of the order of 0.02-0.03 m. The use of a wide rectangular channel approximation introduces an error of 0.10-0.15 m on the predicted water levels. Reducing the bathymetry to a simple bed slope and with mean cross section only, introduces an error in the order of 0.5 m. These results show that when compared to the mean annual amplitude of the Amazon flood wave of 11-12 m, water levels are relatively insensitive to the bathymetry of the channel model. The implication for remote sensing studies of the central Amazon channel, such as those proposed with the Surface Water and Ocean Topography mission (SWOT), is that even relatively crude assumptions regarding the channel bathymetry will be valid in order to derive discharge from water surface slope of the main channel, as long as the mean channel area is approximately correct.

  15. A 6-DOF vibration isolation system for hydraulic hybrid vehicles

    NASA Astrophysics Data System (ADS)

    Nguyen, The; Elahinia, Mohammad; Olson, Walter W.; Fontaine, Paul

    2006-03-01

    This paper presents the results of vibration isolation analysis for the pump/motor component of hydraulic hybrid vehicles (HHVs). The HHVs are designed to combine gasoline/diesel engine and hydraulic power in order to improve the fuel efficiency and reduce the pollution. Electric hybrid technology is being applied to passenger cars with small and medium engines to improve the fuel economy. However, for heavy duty vehicles such as large SUVs, trucks, and buses, which require more power, the hydraulic hybridization is a more efficient choice. In function, the hydraulic hybrid subsystem improves the fuel efficiency of the vehicle by recovering some of the energy that is otherwise wasted in friction brakes. Since the operation of the main component of HHVs involves with rotating parts and moving fluid, noise and vibration are an issue that affects both passengers (ride comfort) as well as surrounding people (drive-by noise). This study looks into the possibility of reducing the transmitted noise and vibration from the hydraulic subsystem to the vehicle's chassis by using magnetorheological (MR) fluid mounts. To this end, the hydraulic subsystem is modeled as a six degree of freedom (6-DOF) rigid body. A 6-DOF isolation system, consisting of five mounts connected to the pump/motor at five different locations, is modeled and simulated. The mounts are designed by combining regular elastomer components with MR fluids. In the simulation, the real loading and working conditions of the hydraulic subsystem are considered and the effects of both shock and vibration are analyzed. The transmissibility of the isolation system is monitored in a wide range of frequencies. The geometry of the isolation system is considered in order to sustain the weight of the hydraulic system without affecting the design of the chassis and the effectiveness of the vibration isolating ability. The simulation results shows reduction in the transmitted vibration force for different working cycles of

  16. Radial deformations of working cylinder of hydraulic Legs depending on their extension

    NASA Astrophysics Data System (ADS)

    Buyalich, G. D.; Buyalich, K. G.; Voyevodin, V. V.

    2015-09-01

    Current methods of calculation of parameters of hydraulic legs of powered supports are in most cases analytical and do not consider all complex of factors. Finite element model was developed to study this problem and used to analyze the influence of hydraulic legs extension on radial deformations of cylinder of different producers of powered supports at variation of hydraulic fluid pressure. It was revealed that radial deformations of cylinders along the axis of hydraulic legs increase in magnitude in direct proportion to the hydraulic fluid pressure and extension. Research results can be recommended to define optimal geometric parameters of hydraulic legs in respect to the minimal radial deformations of hydraulic cylinder increasing its impermeability and improving the work of cup seals. It is recommended to use the obtained results at power support designing.

  17. Design Features for Linguistically-Mediated Meaning Construction: The Relative Roles of the Linguistic and Conceptual Systems in Subserving the Ideational Function of Language

    PubMed Central

    Evans, Vyvyan

    2016-01-01

    Recent research in language and cognitive science proposes that the linguistic system evolved to provide an “executive” control system on the evolutionarily more ancient conceptual system (e.g., Barsalou et al., 2008; Evans, 2009, 2015a,b; Bergen, 2012). In short, the claim is that embodied representations in the linguistic system interface with non-linguistic representations in the conceptual system, facilitating rich meanings, or simulations, enabling linguistically mediated communication. In this paper I build on these proposals by examining the nature of what I identify as design features for this control system. In particular, I address how the ideational function of language—our ability to deploy linguistic symbols to convey meanings of great complexity—is facilitated. The central proposal of this paper is as follows. The linguistic system of any given language user, of any given linguistic system—spoken or signed—facilitates access to knowledge representation—concepts—in the conceptual system, which subserves this ideational function. In the most general terms, the human meaning-making capacity is underpinned by two distinct, although tightly coupled representational systems: the conceptual system and the linguistic system. Each system contributes to meaning construction in qualitatively distinct ways. This leads to the first design feature: given that the two systems are representational—they are populated by semantic representations—the nature and function of the representations are qualitatively different. This proposed design feature I term the bifurcation in semantic representation. After all, it stands to reason that if a linguistic system has a different function, vis-à-vis the conceptual system, which is of far greater evolutionary antiquity, then the semantic representations will be complementary, and as such, qualitatively different, reflecting the functional distinctions of the two systems, in collectively giving rise to

  18. Design Features for Linguistically-Mediated Meaning Construction: The Relative Roles of the Linguistic and Conceptual Systems in Subserving the Ideational Function of Language.

    PubMed

    Evans, Vyvyan

    2016-01-01

    Recent research in language and cognitive science proposes that the linguistic system evolved to provide an "executive" control system on the evolutionarily more ancient conceptual system (e.g., Barsalou et al., 2008; Evans, 2009, 2015a,b; Bergen, 2012). In short, the claim is that embodied representations in the linguistic system interface with non-linguistic representations in the conceptual system, facilitating rich meanings, or simulations, enabling linguistically mediated communication. In this paper I build on these proposals by examining the nature of what I identify as design features for this control system. In particular, I address how the ideational function of language-our ability to deploy linguistic symbols to convey meanings of great complexity-is facilitated. The central proposal of this paper is as follows. The linguistic system of any given language user, of any given linguistic system-spoken or signed-facilitates access to knowledge representation-concepts-in the conceptual system, which subserves this ideational function. In the most general terms, the human meaning-making capacity is underpinned by two distinct, although tightly coupled representational systems: the conceptual system and the linguistic system. Each system contributes to meaning construction in qualitatively distinct ways. This leads to the first design feature: given that the two systems are representational-they are populated by semantic representations-the nature and function of the representations are qualitatively different. This proposed design feature I term the bifurcation in semantic representation. After all, it stands to reason that if a linguistic system has a different function, vis-à-vis the conceptual system, which is of far greater evolutionary antiquity, then the semantic representations will be complementary, and as such, qualitatively different, reflecting the functional distinctions of the two systems, in collectively giving rise to meaning. I consider the

  19. Numerical simulation of thermal-hydraulic generators running in a single regime

    NASA Astrophysics Data System (ADS)

    Chioreanu, Nicolae; Mitran, Tudor; Rus, Alexandru; Beles, Horia

    2014-06-01

    The paper presents the basis for the design of thermal-hydraulic generators running in a single regime. The thermal-hydraulic generators in a single regime running represent an absolute novelty worldwide (a pioneer invention). Based on the methodology concerning this subject, the design calculus for an experimental model was developed.

  20. Identifying Effective Design Features of Technology-Infused Inquiry Learning Modules: A Two-Year Study of Students' Inquiry Abilities

    ERIC Educational Resources Information Center

    Hsu, Ying-Shao; Fang, Su-Chi; Zhang, Wen-Xin; Hsin-Kai, Wu; Wu, Pai-Hsing; Hwang, Fu-Kwun

    2016-01-01

    The two-year study aimed to explore how students' development of different inquiry abilities actually benefited from the design of technology-infused learning modules. Three learning modules on the topics of seasons, environmental issues and air pollution were developed to facilitate students' inquiry abilities: questioning, planning, analyzing,…

  1. Development of an efficient thermo-hydraulic modeling tool to assess dynamic response of large-scale magnet systems

    NASA Astrophysics Data System (ADS)

    Furci, H.; Luongo, C.

    2014-01-01

    A simplified thermo-hydraulic model of the ITER Magnet System has been developed to support the need of fast simulations of ITER superconducting magnet dynamics for the design of control strategies for the helium cryoplant. Modelization of the magnets is made using mainly two standard types of elements, solids and tubes. No Navier-Stoke equations are solved for the hydraulics, but a simple model is implemented which includes property transport, heating and pressure evolution. Implementation in C language is used to investigate the important features on magnet modeling for this particular purpose in terms of superconductor cooling channel description and thermal interaction with surrounding parts (thermal coupling with jackets, presence of the conductor in the model, importance of the central channel). Taking into account these findings, an optimal approach to the thermal modeling of ITER magnets is proposed.

  2. High Speed Strain Measurements Surrounding Hydraulic Fracture in Brittle Hydrogel

    NASA Astrophysics Data System (ADS)

    Steinhardt, Will; Rubinstein, Shmuel

    2015-11-01

    Hydraulic fractures of oil and gas shales occur miles underground, below complex, layered rocks, making measurements of their dynamics, extent, or structure difficult to impossible. Rocks are heterogeneous at a wide range of length scales, and investigating how these non-uniformities affect the propagation and extent of fractures is vital to improving both the safety and efficiency of hydraulic fracturing operations. To study these effects we have developed a model system using brittle, heavily cross-linked hydrogels that we can fracture with fluids and observe with a fast camera. By embedding tracer particles within the gel and using laser sheet microscopy, we obtain three dimensional stress and strain maps of the zone surrounding a hydraulic fracture tip. Gels can also be set in layers or interfaces with tunable strengths or with designed heterogeneities, allowing us to understand the fundamental science of hydraulic fractures and investigate the dynamics of controllably complex materials.

  3. An automated, pre-programmed, multiplexed, hydraulic microvalve.

    PubMed

    Kim, Jitae; Chen, Dafeng; Bau, Haim H

    2009-12-21

    An automated, pre-programmed, multiplexed hydraulic valve actuator is described. The valve is membrane-based and normally open. In contrast to the membrane-based pneumatic valve, the hydraulic valve uses hydraulic liquid to exert the control pressure. The line pressure is controlled with a roller moving over a prefabricated topology. Multiple rollers, each traversing its own track, are assembled into a single carriage, which can be actuated either manually or with a single computer-controlled motor. A valve manifold and roller actuators are designed, fabricated, and tested to demonstrate three-way valve actuation in a pre-determined sequence. The performance of the valve is evaluated and the utility of the valve in the operation of a micro thermal cycler was demonstrated. Hydraulic controllers of the type described here can be operated either manually or under computer control and provide an inexpensive means of controlling flow in lab-on-a-chip devices. PMID:20024041

  4. Herb Hydraulics: Inter- and Intraspecific Variation in Three Ranunculus Species.

    PubMed

    Nolf, Markus; Rosani, Andrea; Ganthaler, Andrea; Beikircher, Barbara; Mayr, Stefan

    2016-04-01

    The requirements of the water transport system of small herbaceous species differ considerably from those of woody species. Despite their ecological importance for many biomes, knowledge regarding herb hydraulics remains very limited. We compared key hydraulic features (vulnerability to drought-induced hydraulic decline, pressure-volume relations, onset of cellular damage, in situ variation of water potential, and stomatal conductance) of three Ranunculus species differing in their soil humidity preferences and ecological amplitude. All species were very vulnerable to water stress (50% reduction in whole-leaf hydraulic conductance [kleaf] at -0.2 to -0.8 MPa). In species with narrow ecological amplitude, the drought-exposed Ranunculus bulbosus was less vulnerable to desiccation (analyzed via loss of kleaf and turgor loss point) than the humid-habitat Ranunculus lanuginosus Accordingly, water stress-exposed plants from the broad-amplitude Ranunculus acris revealed tendencies toward lower vulnerability to water stress (e.g. osmotic potential at full turgor, cell damage, and stomatal closure) than conspecific plants from the humid site. We show that small herbs can adjust to their habitat conditions on interspecific and intraspecific levels in various hydraulic parameters. The coordination of hydraulic thresholds (50% and 88% loss of kleaf, turgor loss point, and minimum in situ water potential) enabled the study species to avoid hydraulic failure and damage to living cells. Reversible recovery of hydraulic conductance, desiccation-tolerant seeds, or rhizomes may allow them to prioritize toward a more efficient but vulnerable water transport system while avoiding the severe effects that water stress poses on woody species. PMID:26896395

  5. Pneumatic actuator with hydraulic control

    NASA Astrophysics Data System (ADS)

    Everett, Hobart R., Jr.

    1992-11-01

    The present invention provides a pneumatically powered actuator having hydraulic control for both locking and controlling the velocity of an output rod without any sponginess. The invention includes a double-acting pneumatic actuator having a bore, a piston slidably engaged within the bore, and a control rod connected to the piston. The double-acting pneumatic actuator is mounted to a frame. A first double-acting hydraulic actuator having a bore, a piston slidably engaged within the bore, and a follower rod mounted to the piston is mounted to the frame such that the follower rod is fixedly connected to the control rod. The maximum translation of the piston within the bore of the first double-acting hydraulic actuator provides a volumetric displacement V1. The present invention also includes a second double-acting hydraulic actuator having a bore, a piston slidably engaged within the bore, and an output rod mounted to the piston. The maximum translation of the piston within the bore of the second double-acting hydraulic actuator provides a volumetric displacement V2, where V2=V1. A pair of fluid ports in each of the first and second double-acting hydraulic cylinders are operably connected by fluid conduits, one of which includes a valve circuit which may be used to control the velocity of the output rod or to lock the output rod in a static position by regulating the flow of hydraulic fluid between the double-acting cylinders.

  6. Design of an efficient real-time algorithm using reduced feature dimension for recognition of speed limit signs.

    PubMed

    Cho, Hanmin; Han, Seungwha; Hwang, Sun-Young

    2013-01-01

    We propose a real-time algorithm for recognition of speed limit signs from a moving vehicle. Linear Discriminant Analysis (LDA) required for classification is performed by using Discrete Cosine Transform (DCT) coefficients. To reduce feature dimension in LDA, DCT coefficients are selected by a devised discriminant function derived from information obtained by training. Binarization and thinning are performed on a Region of Interest (ROI) obtained by preprocessing a detected ROI prior to DCT for further reduction of computation time in DCT. This process is performed on a sequence of image frames to increase the hit rate of recognition. Experimental results show that arithmetic operations are reduced by about 60%, while hit rates reach about 100% compared to previous works. PMID:24453791

  7. Hydraulic accumulator-motor-generator energy regeneration system for a hybrid hydraulic excavator

    NASA Astrophysics Data System (ADS)

    Lin, Tianliang; Wang, Qingfeng

    2012-11-01

    Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger and the time for regenerating energy is so short. At first, the structure of new ERS that combines the advantages of an electric and hydraulic accumulator is analyzed. The energy can be converted into both the electric energy and the hydraulic energy at the lowering of the boom and the generator can still works when the boom stops going down. Then, a method how to set the working pressure of the hydraulic accumulator is proposed. To avoid the excess loss, extra noise and shock pressure, a two-level pressure threshold method that the generator starts to work at the rising edge of the high pressure threshold and stops working at the falling edge of the low pressure threshold is presented to characterize the working mode of the generator. The control strategies on how to control the boom velocity at the lowering of the boom and how to improve the recovery efficiency when the boom stops going down are presented. The test bench of hybrid excavator with ERS is constructed, with which the studies on the influences of ERS on energy conversion efficiency and control performance are carried out. Experimental results show that the proposed ERS features better speed control performance of the boom than traditional ERS. It is also observed that an estimated 45% of the total potential energy could be regenerated at the lowering of the boom in the proposed ERS, and the power level of the generator and the hydraulic motor could be reduced by 60%. Hence, the proposed ERS has obvious advantages over the traditional ERS on the improvement of energy regeneration time, energy efficiency, control performance and economy.

  8. Electrokinetic high pressure hydraulic system

    DOEpatents

    Paul, Phillip H.; Rakestraw, David J.

    2000-01-01

    A compact high pressure hydraulic pump having no moving mechanical parts for converting electric potential to hydraulic force. The electrokinetic pump, which can generate hydraulic pressures greater than 2500 psi, can be employed to compress a fluid, either liquid or gas, and manipulate fluid flow. The pump is particularly useful for capillary-base systems. By combining the electrokinetic pump with a housing having chambers separated by a flexible member, fluid flow, including high pressure fluids, is controlled by the application of an electric potential, that can vary with time.

  9. Removing the influence of feature repetitions on the congruency sequence effect: why regressing out confounds from a nested design will often fall short.

    PubMed

    Schmidt, James R; De Schryver, Maarten; Weissman, Daniel H

    2014-12-01

    This article illustrates a shortcoming of using regression to control for confounds in nested designs. As an example, we consider the congruency sequence effect, which is the observation that the congruency effect in distractor interference (e.g., Stroop) tasks is smaller following incongruent as compared with congruent trials. The congruency sequence effect is often interpreted as indexing conflict adaptation: a relative increase of attention to the target following incongruent trials. However, feature repetitions across consecutive trials can complicate this interpretation. To control for this confound, the standard procedure is to delete all trials with a stimulus or response repetition and analyze the remaining trials. Notebaert and Verguts (2007) present an alternative method that allows researchers to use all trials. Specifically, they employ multiple regression to model conflict adaptation independent of feature repetitions. We show here that this approach fails to account for certain feature repetition effects. Furthermore, modeling these additional effects is typically not possible because of an upper bound on the number of degrees of freedom in the experiment. These findings have important implications for future investigations of conflict adaptation and, more broadly, for all researchers who attempt to regress out confounds in nested designs. PMID:25419672

  10. Alluvial channel hydraulics

    NASA Astrophysics Data System (ADS)

    Ackers, Peter

    1988-07-01

    The development and utilisation of water resources for irrigation, hydropower and public supply can be severely affected by sediment. Where there is a mature and well vegetated landscape, sediment problems may be relatively minor; but where slopes are steep and vegetation sparse, the yield of sediment from the catchment gives high concentrations in the rivers. In utilising these resources, for whatever purpose, an understanding of the hydraulics of alluvial channels is vital. The regime of any conveyance channel in alluvium depends on the interrelationships of sediment transport, channel resistance and bank stability. The regime concept was originally based on empirical relations obtained from observations from canal systems in the Indian subcontinent, and for many years was surrounded by a certain degree of mystique and much scepticism from academics. In more recent years the unabashed empiricism of the original method has been replaced by process-based methods, which have also served as broad confirmation of the classic regime formulae, including their extension to natural channels and meandering channels. The empirical approach to the hydraulics of alluvial channels has thus been updated by physically based formulae for sediment transport and resistance, though there remains some uncertainty about the third function to complete the definition of slope and geometry. Latest thoughts in this respect are that the channel seeks a natural optimum state. Physical modelling using scaled down representations of rivers and estuaries has been used for almost a century, but it requires the correct simulation of the relevant processes. The coming of a better understanding of the physics of sediment transport and the complexity of alluvial channel roughness leads to the conclusion that only in very restricted circumstances can scale models simulate closely the full-size condition. However, the quantification of these processes has been instrumental in the development of

  11. Stem and leaf hydraulic properties are finely coordinated in three tropical rain forest tree species.

    PubMed

    Nolf, Markus; Creek, Danielle; Duursma, Remko; Holtum, Joseph; Mayr, Stefan; Choat, Brendan

    2015-12-01

    Coordination of stem and leaf hydraulic traits allows terrestrial plants to maintain safe water status under limited water supply. Tropical rain forests, one of the world's most productive biomes, are vulnerable to drought and potentially threatened by increased aridity due to global climate change. However, the relationship of stem and leaf traits within the plant hydraulic continuum remains understudied, particularly in tropical species. We studied within-plant hydraulic coordination between stems and leaves in three tropical lowland rain forest tree species by analyses of hydraulic vulnerability [hydraulic methods and ultrasonic emission (UE) analysis], pressure-volume relations and in situ pre-dawn and midday water potentials (Ψ). We found finely coordinated stem and leaf hydraulic features, with a strategy of sacrificing leaves in favour of stems. Fifty percent of hydraulic conductivity (P50 ) was lost at -2.1 to -3.1 MPa in stems and at -1.7 to -2.2 MPa in leaves. UE analysis corresponded to hydraulic measurements. Safety margins (leaf P50 - stem P50 ) were very narrow at -0.4 to -1.4 MPa. Pressure-volume analysis and in situ Ψ indicated safe water status in stems but risk of hydraulic failure in leaves. Our study shows that stem and leaf hydraulics were finely tuned to avoid embolism formation in the xylem. PMID:26032606

  12. Hydraulic Fracturing in Saturated Cohesionless Materials

    NASA Astrophysics Data System (ADS)

    Germanovich, L. N.; Hurt, R. S.; Huang, H.

    2007-12-01

    Based on the developed experimental techniques, hydraulic fracturing in particulate materials has been directly observed in the laboratory. As a result, we suggested several mechanisms of hydraulic fracturing in particulate materials and determined relevant scaling relationships (e.g., the interplay between elastic and plastic processes). While the ongoing work is likely to change at least some conclusions, it is important that the results reported in this work appear to form the framework for modeling and, perhaps, even for (qualitative) interpretation of field data. The observed fracture geometry and the measured pressure injection curves suggest that hydraulic fracturing occurs in soft sediments in the following sequence: (i) cavity expansion, (ii) fracture front initiation, and (iii) propagation of the developed fracture. Our experiments show that liquid can indeed propagate as a crack-like feature when injected into cohesionless saturated materials. Laboratory observations suggest that at the initial stage, the cavity expansion process ends with fracture initiation. Sometimes, the growing fracture resembles penetration of one movable material into another less movable material, which may be a manifestation of the Taylor-like instability. An important conclusion of our work is that all parts of the cohesionless particulate material (including the tip zone of hydraulic fracture) are likely to be in compression. The compressive stress state is an important characteristic of hydraulic fracturing in particulate materials with low, or no, cohesion (such as were used in our experiments). At present, two kinematic mechanisms of fracture propagation, consistent with the compressive stress regime, can be offered. The first mechanism is based on shear bands propagating ahead of the tip of an open fracture. The second is based on the tensile strain ahead of the fracture tip and reduction of the effective stresses to zero within the leak-off zone. Additionally, an

  13. Hydraulic mechanism to limit torsional loads between the IUS and space transportation system orbiter

    NASA Technical Reports Server (NTRS)

    Farmer, James R.

    1986-01-01

    The Inertial Upper Stage (IUS) is a two-stage booster used by NASA and the Defense Department to insert payloads into geosynchronous orbit from low-Earth orbit. The hydraulic mechanism discussed here was designed to perform a specific dynamic and static interface function within the Space Transportation System's Orbiter. Requirements, configuration, and application of the hydraulic mechanism with emphasis on performance and methods of achieving zero external hydraulic leakage are discussed. The hydraulic load-leveler mechanism meets the established design requirements for operation in a low-Earth orbit. Considerable testing was conducted to demonstrate system performance and verification that external leakage had been reduced to zero. Following each flight use of an ASE, all hydraulic mechanism components are carefully inspected for leakage. The ASE, including the hydraulic mechanism, has performed without any anomalies during all IUS flights.

  14. Field measurements in unwadeable natural hydraulic jumps

    NASA Astrophysics Data System (ADS)

    Valle, B.; Pasternack, G.

    2003-04-01

    Recent research in fluvial geomorphology has emphasized the development and application of digital terrain models to better understand process-form relations. However, field measurements in mountain channels have largely been restricted to low velocity or ephemeral flow conditions. To address this problem, a new high-resolution mechanical surveying system was developed at UC Davis and used to measure the 3D bed and water surface topographies of an unwadeable plunging hydraulic jump in the Cache Creek basin, CA. Labeled as the River Truss, the system is capable of making high-resolution form and process measurements over a 30 to 115 m2 area. Bed and water surface DTMs were derived from the field data using AutoCAD. River Truss precision was assessed by DTM differencing the hydraulic jump bed surface topography with a DTM developed from tacheometric survey at low base flows. Bed surface DTMs indicate significant spatial complexity of the underlying bed step in the supercritical flow region and significant downstream bed scour. Water surface DTMs indicate 3D complexity of the plunging flow surface and divergence from 1D free-fall theory. Further study will emphasize the development and deployment of process-based instrumentation such that the complex turbulent air-water flow dynamics associated with natural hydraulic jumps may be better understood. Also, a second generation River Truss that has a larger coverage area and automated data collection has been designed and is now being built.

  15. Hydraulic stud tensioning aids pump performance

    SciTech Connect

    Marchand, G.J.

    1986-03-31

    This article considers the use of hydraulic stud tensioners on mud pump fluid ends. It contains tensioner testing and application. A typical problem involving a fluid end stud is presented to illustrate the use of hydraulic tensioning. Hydraulic stud tensioners give optimum preload reliability over traditional torque tensioning methods. Accurately controlling preload increases stud fatigue life and minimizes maintenance. At one time it was acceptable just to get fluid end connections tight by means of slogging wrenches, impact wrenches, or two of your biggest men on a 10-ft cheater pipe. If the connection did not leak during hydrotest, it was accepted and put into operation. Users of mud pumps are faced with fluid ends that may ''breathe'' excessively due to improper stud preload. Today's equipment is smaller in size and larger in horsepower than ever before, using large retaining studs requiring torques of 3,000 ft-lb and up. In present compact designs, many bolted connections have become virtually inaccessible using traditional tightening procedures. No longer will large wrenches, cheater pipes, and sledge hammers clear surrounding equipment.

  16. In-line hydraulic dashpot

    NASA Astrophysics Data System (ADS)

    Moody, Paul E.

    1992-10-01

    An in-line hydraulic dashpot is disclosed that effectively decelerates the piston of a power cylinder by controllably choking off the oil which is providing pressure to the piston. The in-line hydraulic dashpot of the invention includes a valve spool member movable between an open and closed position along a fluid flow path that supplies oil to the power cylinder. An actuator rod is cooperative with the valve spool member and the piston shaft of the power cylinder to move tile valve spool member between its open and closed positions. The in-line hydraulic dashpot eliminates the clashing of mechanical parts and therewith eliminates the noise that would otherwise be generated thereby. The in-line hydraulic dashpot of the present invention makes possible the adaptation of a fixed stroke power cylinder to applications that call for a variable stroke length.

  17. Hydraulic drive system prevents backlash

    NASA Technical Reports Server (NTRS)

    Acord, J. D.

    1965-01-01

    Hydraulic drive system uses a second drive motor operating at reduced torque. This exerts a relative braking action which eliminates the normal gear train backlash that is intolerable when driving certain heavy loads.

  18. Production Hydraulic Packer Field Test

    SciTech Connect

    Schneller, Tricia; Salas, Jose

    2000-06-30

    In October 1999, the Rocky Mountain Oilfield Testing Center and Halliburton Energy Services cooperated on a field test of Halliburton's new Production Hydraulic Packer technology on Well 46-TPX-10 at Naval Petroleum Reserve No. 3 near Casper, WY. Performance of the packer was evaluated in set and unset operations. The packer's ability to seal the annulus between the casing and tubing was hydraulically tested and the results were recorded.

  19. Design and Control of a Ship Motion Simulation Platform from an Energy Efficiency Perspective

    SciTech Connect

    Lind, Randall F; Jansen, John F; Love, Lonnie J; Lloyd, Peter D; Rowe, John C; Pin, Francois G

    2009-01-01

    Most hydraulic servo systems are designed with little consideration for energy efficiency. Pumps are selected based upon required peak power demands, valves are chosen primarily for their rated flow, actuators for the maximum force. However, the design of a hydraulic servo system has great potential in terms of energy efficiency that has, for the most part, been ignored. This paper describes the design and control of a large-scale ship motion simulation platform that was designed and built at Oak Ridge National Laboratory for the Office of Naval Research. The primary reasons to incorporate energy-efficiency features into the design are cost and size reduction. A preliminary survey of proposed designs based on traditional motion simulation platform configurations (Stuart Platforms) required hydraulic power supplies approaching 1.22 MW. This manuscript describes the combined design and control effort that led to a system with the same performance requirements, however requiring a primary power supply that was less than 112 kW. The objective of this paper is to illustrate alternative design and control approaches that can significantly reduce the power requirements of hydraulic systems and improve the overall energy-efficiency of large-scale hydraulically actuated systems.

  20. A decade of adult intensive care unit design: a study of the physical design features of the best-practice examples.

    PubMed

    Rashid, Mahbub

    2006-01-01

    This article reports a study of the physical design characteristics of a set of adult intensive care units (ICUs), built between 1993 and 2003. These ICUs were recognized as the best-practice examples by the Society of Critical Care Medicine, the American Association of Critical Care Nurses, and the American Institute of Architects. This study is based on a systematic analysis of the materials found on these ICUs in the booklet and videos jointly published by the above organizations in 2005. The study finds that most of these examples of best-practice adult ICUs have the following negative characteristics: (1) they are built as renovation projects with more health and safety hazards during construction; (2) most of them are mixed-service units with more safety and staffing problems; (3) the overall layout and the layout of staff work areas in these ICUs do not have any common design solutions for improved patient and staff outcomes; and (4) in these ICUs, family space is often located outside the unit, and family access to the patient room is restricted, even though family presence at the bedside may be important for improved patient outcomes. Some of these negative characteristics are offset by the following positive characteristics in most ICUs: (1) they have only private patient rooms for improved patient care, safety, privacy, and comfort; (2) most patient beds are freestanding for easy access to patients from all sides; (3) they have handwashing sinks and waste disposal facilities in the patient room for improved safety; and (4) most patient rooms have natural light to help patients with circadian rhythms. The article discusses, in detail, the implications of its findings, and the role of the ICU design community in a very complicated design context. PMID:17063097

  1. Monitoring hydraulic fracturing with seismic emission volume

    NASA Astrophysics Data System (ADS)

    Niu, F.; Tang, Y.; Chen, H.; TAO, K.; Levander, A.

    2014-12-01

    Recent developments in horizontal drilling and hydraulic fracturing have made it possible to access the reservoirs that are not available for massive production in the past. Hydraulic fracturing is designed to enhance rock permeability and reservoir drainage through the creation of fracture networks. Microseismic monitoring has been proven to be an effective and valuable technology to image hydraulic fracture geometry. Based on data acquisition, seismic monitoring techniques have been divided into two categories: downhole and surface monitoring. Surface monitoring is challenging because of the extremely low signal-to-noise ratio of the raw data. We applied the techniques used in earthquake seismology and developed an integrated monitoring system for mapping hydraulic fractures. The system consists of 20 to 30 state-of-the-art broadband seismographs, which are generally about hundreds times more sensible than regular geophones. We have conducted two experiments in two basins with very different geology and formation mechanism in China. In each case, we observed clear microseismic events, which may correspond to the induced seismicity directly associated with fracturing and the triggered ones at pre-existing faults. However, the magnitude of these events is generally larger than magnitude -1, approximately one to two magnitudes larger than those detected by downhole instruments. Spectrum-frequency analysis of the continuous surface recordings indicated high seismic energy associated with injection stages. The seismic energy can be back-projected to a volume that surrounds each injection stage. Imaging seismic emission volume (SEV) appears to be an effective way to map the stimulated reservior volume, as well as natural fractures.

  2. 46 CFR 28.880 - Hydraulic equipment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Hydraulic equipment. 28.880 Section 28.880 Shipping... INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.880 Hydraulic equipment. (a) Each hydraulic system must be... times the system's maximum operating pressure. (c) Each hydraulic system must be equipped with at...

  3. 46 CFR 28.880 - Hydraulic equipment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Hydraulic equipment. 28.880 Section 28.880 Shipping... INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.880 Hydraulic equipment. (a) Each hydraulic system must be... times the system's maximum operating pressure. (c) Each hydraulic system must be equipped with at...

  4. 46 CFR 28.880 - Hydraulic equipment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Hydraulic equipment. 28.880 Section 28.880 Shipping... INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.880 Hydraulic equipment. (a) Each hydraulic system must be... times the system's maximum operating pressure. (c) Each hydraulic system must be equipped with at...

  5. 46 CFR 28.405 - Hydraulic equipment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Hydraulic equipment. 28.405 Section 28.405 Shipping... Operate With More Than 16 Individuals on Board § 28.405 Hydraulic equipment. (a) Each hydraulic system... than four times the system maximum operating pressure. (c) Each hydraulic system must be equipped...

  6. Effects of charge design features on parameters of acoustic and seismic waves and cratering, for SMR chemical surface explosions

    NASA Astrophysics Data System (ADS)

    Gitterman, Y.

    2012-04-01

    A series of experimental on-surface shots was designed and conducted by the Geophysical Institute of Israel at Sayarim Military Range (SMR) in Negev desert, including two large calibration explosions: about 82 tons of strong IMI explosives in August 2009, and about 100 tons of ANFO explosives in January 2011. It was a collaborative effort between Israel, CTBTO, USA and several European countries, with the main goal to provide fully controlled ground truth (GT0) infrasound sources in different weather/wind conditions, for calibration of IMS infrasound stations in Europe, Middle East and Asia. Strong boosters and the upward charge detonation scheme were applied to provide a reduced energy release to the ground and an enlarged energy radiation to the atmosphere, producing enhanced infrasound signals, for better observation at far-regional stations. The following observations and results indicate on the required explosives energy partition for this charge design: 1) crater size and local seismic (duration) magnitudes were found smaller than expected for these large surface explosions; 2) small test shots of the same charge (1 ton) conducted at SMR with different detonation directions showed clearly lower seismic amplitudes/energy and smaller crater size for the upward detonation; 3) many infrasound stations at local and regional distances showed higher than expected peak amplitudes, even after application of a wind-correction procedure. For the large-scale explosions, high-pressure gauges were deployed at 100-600 m to record air-blast properties, evaluate the efficiency of the charge design and energy generation, and provide a reliable estimation of the charge yield. Empirical relations for air-blast parameters - peak pressure, impulse and the Secondary Shock (SS) time delay - depending on distance, were developed and analyzed. The parameters, scaled by the cubic root of estimated TNT equivalent charges, were found consistent for all analyzed explosions, except of SS

  7. Use of MHC II structural features in the design of vaccines for organ-specific autoimmune diseases.

    PubMed

    Moustakas, Antonis K; Papadopoulos, George K

    2009-01-01

    The Major Histocompatibility Complex Class II locus is the primary genetic linkage to autoimmune diseases. Susceptibility to each such disease is linked to different alleles, with a few alleles showing also dominant protection. The design of vaccines for autoimmune diseases is a long sought-after goal. As knowledge about the pathogenesis of these diseases has increased, the tools for such an approach have of necessity been refined. We review below the structural essence of MHC II-linked autoimmune diseases which centers on the binding of antigenic peptides to the disease-linked MHC II proteins, and the consequent activation of cognate TCRs from pathogenic CD4+ T cells. The state of affairs in two organ-specific autoimmune diseases, type 1 diabetes, celiac disease are covered, including attempts to treat these via antigen-specific MHC II-guided measures. We offer a couple of testable suggestions as to how this approach could be improved. PMID:19860675

  8. The AViKA (Adding Value in Knee Arthroplasty) postoperative care navigation trial: rationale and design features

    PubMed Central

    2013-01-01

    Background Utilization of total knee arthroplasty is increasing rapidly. A substantial number of total knee arthroplasty recipients have persistent pain after surgery. Our objective was to design a randomized controlled trial to establish the efficacy of a motivational-interviewing-based telephone intervention aimed at improving patient outcomes and satisfaction following total knee arthroplasty. Methods/Design The study was conducted at Brigham and Women’s Hospital in Boston, Massachusetts. The study focused on individuals 40 years or older with a primary diagnosis of osteoarthritis who were scheduled for total knee arthroplasty. The study compared two management strategies over the first six months postoperatively: 1) enhanced postoperative care with frequent follow-up by a care navigator; 2) usual postoperative care. Those who were randomized into the enhanced postoperative care arm received ten calls from a trained non-clinician care navigator over the first six postoperative months. The navigator used motivational interviewing techniques to engage patients in discussions related to their rehabilitation goals, including patient’s plans for and confidence in achieving those goals. Patients in the usual care arm received standard postoperative management and received no navigator phone calls. Patients in both arms were assessed at baseline, three months, and six months postoperatively. Discussion The primary outcome of the study was improvement in function as measured by the difference in Western Ontario and McMaster Universities Osteoarthritis Index function score between preoperative (baseline) status and six months postoperatively. Data were collected to identify factors that may be related to total knee arthroplasty outcomes, including preoperative pain, pain catastrophizing, self-efficacy, and depression. A formal economic analysis is also planned to determine the cost-effectiveness of the care navigator as a component of total knee arthroplasty care

  9. TEMPEST. Transient 3-D Thermal-Hydraulic

    SciTech Connect

    Eyler, L.L.

    1992-01-31

    TEMPEST is a transient, three-dimensional, hydrothermal program that is designed to analyze a range of coupled fluid dynamic and heat transfer systems of particular interest to the Fast Breeder Reactor (FBR) thermal-hydraulic design community. The full three-dimensional, time-dependent equations of motion, continuity, and heat transport are solved for either laminar or turbulent fluid flow, including heat diffusion and generation in both solid and liquid materials. The equations governing mass, momentum, and energy conservation for incompressible flows and small density variations (Boussinesq approximation) are solved using finite-difference techniques. Analyses may be conducted in either cylindrical or Cartesian coordinate systems. Turbulence is treated using a two-equation model. Two auxiliary plotting programs, SEQUEL and MANPLOT, for use with TEMPEST output are included. SEQUEL may be operated in batch or interactive mode; it generates data required for vector plots, contour plots of scalar quantities, line plots, grid and boundary plots, and time-history plots. MANPLOT reads the SEQUEL-generated data and creates the hardcopy plots. TEMPEST can be a valuable hydrothermal design analysis tool in areas outside the intended FBR thermal-hydraulic design community.

  10. The numerical simulation based on CFD of hydraulic turbine pump

    NASA Astrophysics Data System (ADS)

    Duan, X. H.; Kong, F. Y.; Liu, Y. Y.; Zhao, R. J.; Hu, Q. L.

    2016-05-01

    As the functions of hydraulic turbine pump including self-adjusting and compensation with each other, it is far-reaching to analyze its internal flow by the numerical simulation based on CFD, mainly including the pressure field and the velocity field in hydraulic turbine and pump.The three-dimensional models of hydraulic turbine pump are made by Pro/Engineer software;the internal flow fields in hydraulic turbine and pump are simulated numerically by CFX ANSYS software. According to the results of the numerical simulation in design condition, the pressure field and the velocity field in hydraulic turbine and pump are analyzed respectively .The findings show that the static pressure decreases systematically and the pressure gradient is obvious in flow area of hydraulic turbine; the static pressure increases gradually in pump. The flow trace is regular in suction chamber and flume without spiral trace. However, there are irregular traces in the turbine runner channels which contrary to that in flow area of impeller. Most of traces in the flow area of draft tube are spiral.

  11. Estimating Hydraulic Conductivities in a Fractured Shale Formation from Pressure Pulse Testing and 3d Modeling

    NASA Astrophysics Data System (ADS)

    Courbet, C.; DICK, P.; Lefevre, M.; Wittebroodt, C.; Matray, J.; Barnichon, J.

    2013-12-01

    In the framework of its research on the deep disposal of radioactive waste in shale formations, the French Institute for Radiological Protection and Nuclear Safety (IRSN) has developed a large array of in situ programs concerning the confining properties of shales in their underground research laboratory at Tournemire (SW France). One of its aims is to evaluate the occurrence and processes controlling radionuclide migration through the host rock, from the disposal system to the biosphere. Past research programs carried out at Tournemire covered mechanical, hydro-mechanical and physico-chemical properties of the Tournemire shale as well as water chemistry and long-term behaviour of the host rock. Studies show that fluid circulations in the undisturbed matrix are very slow (hydraulic conductivity of 10-14 to 10-15 m.s-1). However, recent work related to the occurrence of small scale fractures and clay-rich fault gouges indicate that fluid circulations may have been significantly modified in the vicinity of such features. To assess the transport properties associated with such faults, IRSN designed a series of in situ and laboratory experiments to evaluate the contribution of both diffusive and advective process on water and solute flux through a clay-rich fault zone (fault core and damaged zone) and in an undisturbed shale formation. As part of these studies, Modular Mini-Packer System (MMPS) hydraulic testing was conducted in multiple boreholes to characterize hydraulic conductivities within the formation. Pressure data collected during the hydraulic tests were analyzed using the nSIGHTS (n-dimensional Statistical Inverse Graphical Hydraulic Test Simulator) code to estimate hydraulic conductivity and formation pressures of the tested intervals. Preliminary results indicate hydraulic conductivities of 5.10-12 m.s-1 in the fault core and damaged zone and 10-14 m.s-1 in the adjacent undisturbed shale. Furthermore, when compared with neutron porosity data from borehole

  12. The hydraulic system of trees: theoretical framework and numerical simulation

    PubMed

    Fruh; Kurth

    1999-12-21

    Empirical studies pose the problem of the physiological integration of the tree organism, which is also important on the scale of ecosystems. Recently, spatially distributed models emerged, which approach this problem by reflecting the close linkage between physiological processes and the structures of trees and tree stands. In the case of water flow, the tree organism can be regarded as hydraulic system and the branched tree architecture as hydraulic network. Previous models of the hydraulic system either did not take into account the network structure, or they had shortcomings regarding the translation of the underlying physiological assumptions by the discrete computation method. We have developed a theoretical framework which takes the form of a numerical simulation model of tree water flow. A discrete initial boundary value problem (IBVP) combines the phenomena of Darcy flow, water storage and conductivity losses in the hydraulic network. The software HYDRA computes the solution of the IBVP. The theoretical derivation and model tests corroborate the consistent translation of the physiological assumptions by the computational method. Simulation studies enabled us to formulate hypotheses on the following points: (1) differences in the hydraulic segmentation between Picea abies and Thuja occidentalis, (2) responses of the hydraulic system to rapid transpiration changes and to a scenario of drought stress, and (3) how these responses depend on architectural quantities of the trees. The simulation studies demonstrated our possibilities of deriving theoretically well-founded hypotheses about the functioning of the hydraulic system and its relation to system structure. The numerical simulation model is designed as a tool for structure-function studies, which is able to treat tree architecture as independent variable. The model supports the integration of data on tree level, and it can be used for computer experiments which quantify the dynamics of the hydraulic

  13. 1 alpha,25-dihydroxyvitamin D3 analogs featuring aromatic and heteroaromatic rings: design, synthesis, and preliminary biological testing.

    PubMed

    Posner, G H; Li, Z; White, M C; Vinader, V; Takeuchi, K; Guggino, S E; Dolan, P; Kensler, T W

    1995-10-27

    Aromatic compounds 2a-c, analogs of 1 alpha, 25-dihydroxyvitamin (calcitriol, 1), and heteroaromatic compounds 4a-c and 5a-c, analogs of 19-nor-1 alpha, 25-dihydroxyvitamin D3 (3), were designed to simulate the topology of their biologically potent parent compounds while avoiding previtamin D equilibrium. Convergent and facile total syntheses of the analogs (+)-2b, (+)-2c, (-)-4b, and (-)-5b were achieved via carbonyl addition of regiospecifically formed organolithium nucleophiles to the enantiomerically pure C,D-ring ketone (+)-17, characteristic of natural calcitriol (1). Likewise, hybrid analogs 20a-c were prepared to determine whether incorporation of a known potentiating side chain would lead to increased biological activity. Preliminary in vitro biological testing showed that aromatic analogs (+)-2b, (+)-2c, and 20a-c as well as heteroaromatic analogs (-)-4b and (-)-5b have very low affinities for the calf thymus vitamin D receptor but considerable antiproliferative activities in murine keratinocytes at micromolar concentration. No biological advantage was observed in this keratinocyte assay for the doubly modified hybrid analogs 20a-c over the singly modified parent (+)-2b. Analog (+)-2b, but surprisingly not the corresponding analog 20b differing from (+)-2b only in the side chain, showed considerable activity in nongenomic opening of calcium channels in rat osteosarcoma cells. PMID:7473581

  14. Current experience in testing mitochondrial nutrients in disorders featuring oxidative stress and mitochondrial dysfunction: rational design of chemoprevention trials.

    PubMed

    Pagano, Giovanni; Aiello Talamanca, Annarita; Castello, Giuseppe; Cordero, Mario D; d'Ischia, Marco; Gadaleta, Maria Nicola; Pallardó, Federico V; Petrović, Sandra; Tiano, Luca; Zatterale, Adriana

    2014-01-01

    An extensive number of pathologies are associated with mitochondrial dysfunction (MDF) and oxidative stress (OS). Thus, mitochondrial cofactors termed "mitochondrial nutrients" (MN), such as α-lipoic acid (ALA), Coenzyme Q10 (CoQ10), and l-carnitine (CARN) (or its derivatives) have been tested in a number of clinical trials, and this review is focused on the use of MN-based clinical trials. The papers reporting on MN-based clinical trials were retrieved in MedLine up to July 2014, and evaluated for the following endpoints: (a) treated diseases; (b) dosages, number of enrolled patients and duration of treatment; (c) trial success for each MN or MN combinations as reported by authors. The reports satisfying the above endpoints included total numbers of trials and frequencies of randomized, controlled studies, i.e., 81 trials testing ALA, 107 reports testing CoQ10, and 74 reports testing CARN, while only 7 reports were retrieved testing double MN associations, while no report was found testing a triple MN combination. A total of 28 reports tested MN associations with "classical" antioxidants, such as antioxidant nutrients or drugs. Combinations of MN showed better outcomes than individual MN, suggesting forthcoming clinical studies. The criteria in study design and monitoring MN-based clinical trials are discussed. PMID:25380523

  15. Current Experience in Testing Mitochondrial Nutrients in Disorders Featuring Oxidative Stress and Mitochondrial Dysfunction: Rational Design of Chemoprevention Trials

    PubMed Central

    Pagano, Giovanni; Aiello Talamanca, Annarita; Castello, Giuseppe; Cordero, Mario D.; d’Ischia, Marco; Gadaleta, Maria Nicola; Pallardó, Federico V.; Petrović, Sandra; Tiano, Luca; Zatterale, Adriana

    2014-01-01

    An extensive number of pathologies are associated with mitochondrial dysfunction (MDF) and oxidative stress (OS). Thus, mitochondrial cofactors termed “mitochondrial nutrients” (MN), such as α-lipoic acid (ALA), Coenzyme Q10 (CoQ10), and l-carnitine (CARN) (or its derivatives) have been tested in a number of clinical trials, and this review is focused on the use of MN-based clinical trials. The papers reporting on MN-based clinical trials were retrieved in MedLine up to July 2014, and evaluated for the following endpoints: (a) treated diseases; (b) dosages, number of enrolled patients and duration of treatment; (c) trial success for each MN or MN combinations as reported by authors. The reports satisfying the above endpoints included total numbers of trials and frequencies of randomized, controlled studies, i.e., 81 trials testing ALA, 107 reports testing CoQ10, and 74 reports testing CARN, while only 7 reports were retrieved testing double MN associations, while no report was found testing a triple MN combination. A total of 28 reports tested MN associations with “classical” antioxidants, such as antioxidant nutrients or drugs. Combinations of MN showed better outcomes than individual MN, suggesting forthcoming clinical studies. The criteria in study design and monitoring MN-based clinical trials are discussed. PMID:25380523

  16. Hydraulic Tomography: Continuity and Discontinuity of High-K and Low-K Zones.

    PubMed

    Hochstetler, David L; Barrash, Warren; Leven, Carsten; Cardiff, Michael; Chidichimo, Francesco; Kitanidis, Peter K

    2016-03-01

    Hydraulic tomography is an emerging field and modeling method that provides a continuous hydraulic conductivity (K) distribution for an investigated region. Characterization approaches that rely on interpolation between one-dimensional (1D) profiles have limited ability to accurately identify high-K channels, juxtapositions of lenses with high K contrast, and breaches in layers or channels between such profiles. However, locating these features is especially important for groundwater flow and transport modeling, and for design and operation of in situ remediation in complex hydrogeologic environments. We use transient hydraulic tomography to estimate 3D K in a volume of 15-m diameter by 20-m saturated thickness in a highly heterogeneous unconfined alluvial (clay to sand-and-gravel) aquifer with a K range of approximately seven orders of magnitude at an active industrial site in Assemini, Sardinia, Italy. A modified Levenberg-Marquardt algorithm was used for geostatistical inversion to deal with the nonlinear nature of the highly heterogeneous system. The imaging results are validated with pumping tests not used in the tomographic inversion. These tests were conducted from three of five clusters of continuous multichannel tubing (CMTs) installed for observation in the tomographic testing. Locations of high-K continuity and discontinuity, juxtaposition of very high-K and very low-K lenses, and low-K "plugs" are evident in regions of the investigated volume where they likely would not have been identified with interpolation from 1D profiles at the positions of the pumping well and five CMT clusters. Quality assessment methods identified a suspect high-K feature between the tested volume and a lateral boundary of the model. PMID:26096272

  17. Lead users’ ideas on core features to support physical activity in rheumatoid arthritis: a first step in the development of an internet service using participatory design

    PubMed Central

    2014-01-01

    Background Despite the growing evidence of the benefits of physical activity (PA) in individuals with rheumatoid arthritis (RA), the majority is not physically active enough. An innovative strategy is to engage lead users in the development of PA interventions provided over the internet. The aim was to explore lead users’ ideas and prioritization of core features in a future internet service targeting adoption and maintenance of healthy PA in people with RA. Methods Six focus group interviews were performed with a purposively selected sample of 26 individuals with RA. Data were analyzed with qualitative content analysis and quantification of participants’ prioritization of most important content. Results Six categories were identified as core features for a future internet service: up-to-date and evidence-based information and instructions, self-regulation tools, social interaction, personalized set-up, attractive design and content, and access to the internet service. The categories represented four themes, or core aspects, important to consider in the design of the future service: (1) content, (2) customized options, (3) user interface and (4) access and implementation. Conclusions This is, to the best of our knowledge, the first study involving people with RA in the development of an internet service to support the adoption and maintenance of PA. Participants helped identifying core features and aspects important to consider and further explore during the next phase of development. We hypothesize that involvement of lead users will make transfer from theory to service more adequate and user-friendly and therefore will be an effective mean to facilitate PA behavior change. PMID:24655757

  18. Total System Performance Assessment-License Application Design Selection (LADS) Phase 1 Analysis of Surface Modification Consisting of Addition of Alluvium (Feature 23a)

    SciTech Connect

    N. Erb

    1999-06-11

    The objective of this report is to document the analysis that was conducted to evaluate the effect of a potential change to the TSPA-VA base case design that could improve long-term repository performance. The design feature evaluated in this report is a modification of the topographic surface of Yucca Mountain. The modification consists of covering the land surface immediately above the repository foot-print with a thick layer of unconsolidated material utilizing rip-rap and plants to mitigate erosion. This surface modification is designated as Feature 23a or simply abbreviated as F23a. The fundamental aim of F23a is to reduce the net infiltration into the unsaturated zone by enhancing the potential for evapotranspiratiration at the surface; such a change would, in turn, reduce the seepage flux and the rate of radionuclide releases from the repository. Field and modeling studies of water movement in the unsaturated zone have indicated that shallow infiltration at the surface is almost negligible in locations where the bedrock is covered by a sufficiently thick soil layer. In addition to providing storage for meteoric water, a thick soil layer would slow the downward movement of soil moisture to such an extent that evaporation and transpiration could easily transfer most of the soil-water back to the atmosphere. Generic requirements for the effectiveness of this design feature are two-fold. First, the soil layer above the repository foot-print must be thick enough to provide sufficient storage of meteoric water (from episodic precipitation events) and accommodate plant roots. Second, the added soil layer must be engineered so as to mitigate thinning by erosional processes and have sufficient thickness to accommodate the roots of common desert plants. Under these two conditions, it is reasonable to expect that modification would be effective for a significant time period and the net infiltration and deep percolation flux would be reduced by orders of magnitude lower

  19. Mapping Three-Dimensional Hydraulic Heterogeneities in Fractured Granite through Transient Hydraulic Tomography

    NASA Astrophysics Data System (ADS)

    Zha, Y.; Yeh, T. C. J.; Illman, W. A.; Tanaka, T.; Bruines, P.; Onoe, H.; Saegusa, H.; Mao, D.

    2014-12-01

    Between 2005 and 2010, three independent sequential pumping tests were conducted in a fractured granite formation at the Mizunami Underground Research Laboratory (MIU) site in central Japan. Additional pumping operations were undertaken in the course of excavation of two vertical shafts at the site. During these events, groundwater responses were monitored in multiple observation intervals in several shallow and deep boreholes. In this study, we first visually inspected these responses at all observation intervals induced by each pumping event. We found that some intervals at far-distance boreholes showed rapid, and strong responses, while intervals of boreholes near the vicinity of the pumping locations showed little responses. Moreover, the locations of the rapid and slow responses varied with pumping locations. This preliminary inspection suggested that some boreholes are likely connected via fractures and some are separated by flow barrier(s). Subsequently, these drawdown data sets were analyzed using a three-dimensional (3-D) transient hydraulic tomography (HT) code to estimate the hydraulic conductivity (K) and specific storage (Ss) distributions. Results of the analysis depicted several large-scale high K and low K zones and some small-scale features at the MIU site. The locations of these high and low K estimates explain the observed fast and slow groundwater responses, and corroborate with the locations of fractures and fault zones estimated based on geologic information. The HT analysis nevertheless provides a detailed description of the hydraulic characteristics of the fracture and fault zones.

  20. Estimation of Hydraulic Property of an Unconfined Aquifer by GPR

    NASA Astrophysics Data System (ADS)

    Lu, Qi; Sato, Motoyuki

    2007-06-01

    Controlled water productions were performed at a water source area of Ulaanbaatar city, Mongolia to evaluate the effectiveness of ground penetrating radar (GPR) for detecting and monitoring dynamic groundwater movements in the subsurface and for estimating the hydraulic properties of the aquifer. Field experiments in Ulaanbaatar were carried out in 2001 and 2002. GPR data were acquired using 100 MHz antennas. This paper reports the results of GPR methods to monitor the groundwater migration caused by the pumping operation and GPR’s potential ability to estimate hydraulic properties of the aquifer. The GPR data sets were acquired very carefully by locating the antenna position accurately. The residual trace shows a feature that is a combination of the water level reflections acquired at two different times in the pumping test. It helped to determine travel time and its effective reflection point from the top of the water saturated zone. The residual wavelet varies versus offset from the pumping well for a given residual image. Common midpoint (CMP) data and velocity analysis indicated the depth of the water table and the water content in the unsaturated and saturated zone. Combining hydrogeologic data with quantitative information yielded by GPR data, hydraulic properties of the aquifer could be estimated by assuming a hydraulic model. It was concluded that GPR can be successfully employed to monitor groundwater migration and to estimate hydraulic properties of the aquifer.

  1. Multivariate distributions of soil hydraulic parameters

    NASA Astrophysics Data System (ADS)

    Qu, Wei; Pachepsky, Yakov; Huisman, Johan Alexander; Martinez, Gonzalo; Bogena, Heye; Vereecken, Harry

    2014-05-01

    on pedotransfer relationships not only within a given textural class but also on pedotransfer relationships within other textural classes since the pedotransfer relationships are developed across the database containing data for several textural classes. Therefore, joint multivariate parameter distributions for a specific class may not be sufficiently accurate. Currently PTF may give the best prediction of the parameter itself, but they are not designed to estimate correlations between parameters. Covariance matrices for soil hydraulic parameters present an additional type of pedotransfer information that needs to be acquired and used whenever random sets of those parameters are to be generated.

  2. Hydraulic Apparatus for Mechanical Testing of Nuts

    NASA Technical Reports Server (NTRS)

    Hinkel, Todd J.; Dean, Richard J.; Hacker, Scott C.; Harrington, Douglas W.; Salazar, Frank

    2004-01-01

    The figure depicts an apparatus for mechanical testing of nuts. In the original application for which the apparatus was developed, the nuts are of a frangible type designed for use with pyrotechnic devices in spacecraft applications in which there are requirements for rapid, one-time separations of structures that are bolted together. The apparatus can also be used to test nonfrangible nuts engaged without pyrotechnic devices. This apparatus was developed to replace prior testing systems that were extremely heavy and immobile and characterized by long setup times (of the order of an hour for each nut to be tested). This apparatus is mobile, and the setup for each test can now be completed in about five minutes. The apparatus can load a nut under test with a static axial force of as much as 6.8 x 10(exp 5) lb (3.0 MN) and a static moment of as much as 8.5 x 10(exp 4) lb in. (9.6 x 10(exp 3) N(raised dot)m) for a predetermined amount of time. In the case of a test of a frangible nut, the pyrotechnic devices can be exploded to break the nut while the load is applied, in which case the breakage of the nut relieves the load. The apparatus can be operated remotely for safety during an explosive test. The load-generating portion of the apparatus is driven by low-pressure compressed air; the remainder of the apparatus is driven by 110-Vac electricity. From its source, the compressed air is fed to the apparatus through a regulator and a manually operated valve. The regulated compressed air is fed to a pneumatically driven hydraulic pump, which pressurizes oil in a hydraulic cylinder, thereby causing a load to be applied via a hydraulic nut (not to be confused with the nut under test). During operation, the hydraulic pressure is correlated with the applied axial load, which is verified by use of a load cell. Prior to operation, one end of a test stud (which could be an ordinary threaded rod or bolt) is installed in the hydraulic nut. The other end of the test stud passes

  3. Hydraulic integration and shrub growth form linked across continental aridity gradients

    PubMed Central

    Schenk, H. Jochen; Espino, Susana; Goedhart, Christine M.; Nordenstahl, Marisa; Cabrera, Hugo I. Martinez; Jones, Cynthia S.

    2008-01-01

    Both engineered hydraulic systems and plant hydraulic systems are protected against failure by resistance, reparability, and redundancy. A basic rule of reliability engineering is that the level of independent redundancy should increase with increasing risk of fatal system failure. Here we show that hydraulic systems of plants function as predicted by this engineering rule. Hydraulic systems of shrubs sampled along two transcontinental aridity gradients changed with increasing aridity from highly integrated to independently redundant modular designs. Shrubs in humid environments tend to be hydraulically integrated, with single, round basal stems, whereas dryland shrubs typically have modular hydraulic systems and multiple, segmented basal stems. Modularity is achieved anatomically at the vessel-network scale or developmentally at the whole-plant scale through asymmetric secondary growth, which results in a semiclonal or clonal shrub growth form that appears to be ubiquitous in global deserts. PMID:18678893

  4. From the Kinetic Energy Recovery System to the Thermo-Hydraulic Hybrid Motor Vehicle

    NASA Astrophysics Data System (ADS)

    Cristescu, Corneliu; Drumea, Petrin; Guta, Dragos; Dumitrescu, Catalin

    2011-12-01

    The paper presents some theoretical and experimental results obtained by the Hydraulics and Pneumatics Research Institute INOE 2000-IHP with its partners, regarding the creating of one hydraulic system able to recovering the kinetic energy of the motor vehicles, in the braking phases, and use this recovered energy in the starting and accelerating phases. Also, in the article is presented a testing stand, which was especially designed for testing the hydraulic system for recovery the kinetic energy. Through mounting of the kinetic energy recovering hydraulic system, on one motor vehicle, this vehicle became a thermo-hydraulic hybrid vehicle. Therefore, the dynamic behavior was analyzed for the whole hybrid motor vehicle, which includes the energy recovery system. The theoretical and experimental results demonstrate the possible performances of the hybrid vehicle and that the kinetic energy recovery hydraulic systems are good means to increase energy efficiency of the road motor vehicles and to decrease of the fuel consumption.

  5. Hydraulic integration and shrub growth form linked across continental aridity gradients.

    PubMed

    Schenk, H Jochen; Espino, Susana; Goedhart, Christine M; Nordenstahl, Marisa; Cabrera, Hugo I Martinez; Jones, Cynthia S

    2008-08-12

    Both engineered hydraulic systems and plant hydraulic systems are protected against failure by resistance, reparability, and redundancy. A basic rule of reliability engineering is that the level of independent redundancy should increase with increasing risk of fatal system failure. Here we show that hydraulic systems of plants function as predicted by this engineering rule. Hydraulic systems of shrubs sampled along two transcontinental aridity gradients changed with increasing aridity from highly integrated to independently redundant modular designs. Shrubs in humid environments tend to be hydraulically integrated, with single, round basal stems, whereas dryland shrubs typically have modular hydraulic systems and multiple, segmented basal stems. Modularity is achieved anatomically at the vessel-network scale or developmentally at the whole-plant scale through asymmetric secondary growth, which results in a semiclonal or clonal shrub growth form that appears to be ubiquitous in global deserts. PMID:18678893

  6. Current and anticipated uses of thermal hydraulic codes in Korea

    SciTech Connect

    Kim, Kyung-Doo; Chang, Won-Pyo

    1997-07-01

    In Korea, the current uses of thermal hydraulic codes are categorized into 3 areas. The first application is in designing both nuclear fuel and NSSS. The codes have usually been introduced based on the technology transfer programs agreed between KAERI and the foreign vendors. Another area is in the supporting of the plant operations and licensing by the utility. The third category is research purposes. In this area assessments and some applications to the safety issue resolutions are major activities using the best estimate thermal hydraulic codes such as RELAP5/MOD3 and CATHARE2. Recently KEPCO plans to couple thermal hydraulic codes with a neutronics code for the design of the evolutionary type reactor by 2004. KAERI also plans to develop its own best estimate thermal hydraulic code, however, application range is different from KEPCO developing code. Considering these activities, it is anticipated that use of the best estimate hydraulic analysis code developed in Korea may be possible in the area of safety evaluation within 10 years.

  7. AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT X, AUTOMATIC TRANSMISSIONS--HYDRAULIC SYSTEMS (PART II).

    ERIC Educational Resources Information Center

    Human Engineering Inst., Cleveland, OH.

    THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO PROVIDE A SUMMARY OF MAINTENANCE PROCEDURES FOR AUTOMATIC TRANSMISSIONS USED ON DIESEL POWERED VEHICLES. TOPICS ARE (1) CHECKING THE HYDRAULIC SYSTEM, (2) SERVICING THE HYDRAULIC SYSTEM, (3) EXAMINING THE RANGE CONTROL VALVE, (4) EXAMINING THE LOCK-UP AND FLOW VALVE, (5) EXAMINING THE MAIN REGULATOR…

  8. Final Plan to Study the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources

    EPA Science Inventory

    The overall purpose of this study is to elucidate the relationship, if any, between hydraulic fracturing and drinking water resources. More specifically, the study has been designed to assess the potential impacts of hydraulic fracturing on drinking water resources and to identif...

  9. The Design and Development of Online Course Materials: Some Features and Recommendations (El diseño y desarrollo de materiales para cursos en línea: algunos rasgos y recomendaciones)

    ERIC Educational Resources Information Center

    Cuesta, Liliana

    2010-01-01

    This article discusses various features in the design and implementation of online course materials. The author provides a critical review of some instructional design patterns and expands on the alignment among instruction, motivation and learners' performances as part of a curriculum design process. In this context, the author emphasizes…

  10. Applying hydraulic transient analysis: The Grizzly Hydro Project

    SciTech Connect

    Logan, T.H.; Stutsman, R.D. )

    1992-04-01

    No matter the size of the hydro plant, if it has a long waterway and will operate in peaking mode, the project designer needs to address the issue of hydraulic transients-known as water hammer-early in the design. This article describes the application of transient analysis to the design of a 20-MW hydro plant in California. In this case, a Howell Bunger valve was used as a pressure regulating valve to control transient pressures and speed rise.

  11. Complex Fluids and Hydraulic Fracturing.

    PubMed

    Barbati, Alexander C; Desroches, Jean; Robisson, Agathe; McKinley, Gareth H

    2016-06-01

    Nearly 70 years old, hydraulic fracturing is a core technique for stimulating hydrocarbon production in a majority of oil and gas reservoirs. Complex fluids are implemented in nearly every step of the fracturing process, most significantly to generate and sustain fractures and transport and distribute proppant particles during and following fluid injection. An extremely wide range of complex fluids are used: naturally occurring polysaccharide and synthetic polymer solutions, aqueous physical and chemical gels, organic gels, micellar surfactant solutions, emulsions, and foams. These fluids are loaded over a wide range of concentrations with particles of varying sizes and aspect ratios and are subjected to extreme mechanical and environmental conditions. We describe the settings of hydraulic fracturing (framed by geology), fracturing mechanics and physics, and the critical role that non-Newtonian fluid dynamics and complex fluids play in the hydraulic fracturing process. PMID:27070765

  12. Electrokinetic high pressure hydraulic system

    DOEpatents

    Paul, Phillip H.; Rakestraw, David J.; Arnold, Don W.; Hencken, Kenneth R.; Schoeniger, Joseph S.; Neyer, David W.

    2003-06-03

    An electrokinetic high pressure hydraulic pump for manipulating fluids in capillary-based system. The pump uses electro-osmotic flow to provide a high pressure hydraulic system, having no moving mechanical parts, for pumping and/or compressing fluids, for providing valve means and means for opening and closing valves, for controlling fluid flow rate, and manipulating fluid flow generally and in capillary-based systems (microsystems), in particular. The compact nature of the inventive high pressure hydraulic pump provides the ability to construct a micro-scale or capillary-based HPLC system that fulfills the desire for small sample quantity, low solvent consumption, improved efficiency, the ability to run samples in parallel, and field portability. Control of pressure and solvent flow rate is achieved by controlling the voltage applied to an electrokinetic pump.

  13. Electrokinetic high pressure hydraulic system

    DOEpatents

    Paul, Phillip H.; Rakestraw, David J.; Arnold, Don W.; Hencken, Kenneth R.; Schoeniger, Joseph S.; Neyer, David W.

    2001-01-01

    An electrokinetic high pressure hydraulic pump for manipulating fluids in capillary-based systems. The pump uses electro-osmotic flow to provide a high pressure hydraulic system, having no moving mechanical parts, for pumping and/or compressing fluids, for providing valve means and means for opening and closing valves, for controlling fluid flow rate, and manipulating fluid flow generally and in capillary-based systems (Microsystems), in particular. The compact nature of the inventive high pressure hydraulic pump provides the ability to construct a micro-scale or capillary-based HPLC system that fulfills the desire for small sample quantity, low solvent consumption, improved efficiency, the ability to run samples in parallel, and field portability. Control of pressure and solvent flow rate is achieved by controlling the voltage applied to an electrokinetic pump.

  14. Method for directional hydraulic fracturing

    DOEpatents

    Swanson, David E.; Daly, Daniel W.

    1994-01-01

    A method for directional hydraulic fracturing using borehole seals to confine pressurized fluid in planar permeable regions, comprising: placing a sealant in the hole of a structure selected from geologic or cemented formations to fill the space between a permeable planar component and the geologic or cemented formation in the vicinity of the permeable planar component; making a hydraulic connection between the permeable planar component and a pump; permitting the sealant to cure and thereby provide both mechanical and hydraulic confinement to the permeable planar component; and pumping a fluid from the pump into the permeable planar component to internally pressurize the permeable planar component to initiate a fracture in the formation, the fracture being disposed in the same orientation as the permeable planar component.

  15. A Novel Approach in Quantifying the Effect of Urban Design Features on Local-Scale Air Pollution in Central Urban Areas.

    PubMed

    Miskell, Georgia; Salmond, Jennifer; Longley, Ian; Dirks, Kim N

    2015-08-01

    Differences in urban design features may affect emission and dispersion patterns of air pollution at local-scales within cities. However, the complexity of urban forms, interdependence of variables, and temporal and spatial variability of processes make it difficult to quantify determinants of local-scale air pollution. This paper uses a combination of dense measurements and a novel approach to land-use regression (LUR) modeling to identify key controls on concentrations of ambient nitrogen dioxide (NO2) at a local-scale within a central business district (CBD). Sixty-two locations were measured over 44 days in Auckland, New Zealand at high density (study area 0.15 km(2)). A local-scale LUR model was developed, with seven variables identified as determinants based on standard model criteria. A novel method for improving standard LUR design was developed using two independent data sets (at local and "city" scales) to generate improved accuracy in predictions and greater confidence in results. This revised multiscale LUR model identified three urban design variables (intersection, proximity to a bus stop, and street width) as having the more significant determination on local-scale air quality, and had improved adaptability between data sets. PMID:26151151

  16. FOREWORD: 26th IAHR Symposium on Hydraulic Machinery and Systems

    NASA Astrophysics Data System (ADS)

    Wu, Yulin; Wang, Zhengwei; Liu, Shuhong; Yuan, Shouqi; Luo, Xingqi; Wang, Fujun

    2012-11-01

    was molded into a polytechnic institute focusing on engineering in the nationwide restructuring of universities and colleges undertaken in 1952. At present, the university has 14 schools and 56 departments with faculties in science, engineering, humanities, law, medicine, history, philosophy, economics, management, education and art. The University now has over 25 900 students, including 13 100 undergraduates and 12 800 graduate students. As one of China's most renowned universities, Tsinghua has become an important institution for fostering talents and scientific research. The International Association of Hydro-Environment Engineering and Research (IAHR) particularly promotes the advancement and exchange of knowledge through working groups, specialty symposia, congresses, and publications on water resources, river and coastal hydraulics, risk analysis, energy, environment, disaster prevention, and industrial processes. The IAHR Committee on Hydraulic Machinery and Systems deals with the advancement of technology associated with the understanding of steady and unsteady flow characteristics in hydraulic machinery and conduit systems connected to the machinery. The technology elements include the fluid behaviour within machine components, hydro-elastic behaviour of machine components, cavitation and two phase flow in turbines and pumps, hydraulic machine and plant control systems, the use of hydraulic machines to improve water quality, and even considerations to improve fish survival in their passage through hydro plants. The main emphases of the IAHR Committee on Hydraulic Machinery and Systems are to stimulate research and understanding of the technologies associated with hydraulic machinery and to promote interaction between the machine designers, machine users, the academic community, and the community as a whole. Hydraulic machinery is both cost effective and environmentally friendly. The goals of the IAHR Committee on Hydraulic Machinery and Systems are to improve

  17. Electokinetic high pressure hydraulic system

    DOEpatents

    Paul, Phillip H.; Rakestraw, David J.

    2000-01-01

    A compact high pressure hydraulic system having no moving parts for converting electric potential to hydraulic force and for manipulating fluids. Electro-osmotic flow is used to provide a valve and means to compress a fluid or gas in a capillary-based system. By electro-osmotically moving an electrolyte between a first position opening communication between a fluid inlet and outlet and a second position closing communication between the fluid inlet and outlet the system can be configured as a valve. The system can also be used to generate forces as large as 2500 psi that can be used to compress a fluid, either a liquid or a gas.

  18. FOREWORD: 26th IAHR Symposium on Hydraulic Machinery and Systems

    NASA Astrophysics Data System (ADS)

    Wu, Yulin; Wang, Zhengwei; Liu, Shuhong; Yuan, Shouqi; Luo, Xingqi; Wang, Fujun

    2012-11-01

    was molded into a polytechnic institute focusing on engineering in the nationwide restructuring of universities and colleges undertaken in 1952. At present, the university has 14 schools and 56 departments with faculties in science, engineering, humanities, law, medicine, history, philosophy, economics, management, education and art. The University now has over 25 900 students, including 13 100 undergraduates and 12 800 graduate students. As one of China's most renowned universities, Tsinghua has become an important institution for fostering talents and scientific research. The International Association of Hydro-Environment Engineering and Research (IAHR) particularly promotes the advancement and exchange of knowledge through working groups, specialty symposia, congresses, and publications on water resources, river and coastal hydraulics, risk analysis, energy, environment, disaster prevention, and industrial processes. The IAHR Committee on Hydraulic Machinery and Systems deals with the advancement of technology associated with the understanding of steady and unsteady flow characteristics in hydraulic machinery and conduit systems connected to the machinery. The technology elements include the fluid behaviour within machine components, hydro-elastic behaviour of machine components, cavitation and two phase flow in turbines and pumps, hydraulic machine and plant control systems, the use of hydraulic machines to improve water quality, and even considerations to improve fish survival in their passage through hydro plants. The main emphases of the IAHR Committee on Hydraulic Machinery and Systems are to stimulate research and understanding of the technologies associated with hydraulic machinery and to promote interaction between the machine designers, machine users, the academic community, and the community as a whole. Hydraulic machinery is both cost effective and environmentally friendly. The goals of the IAHR Committee on Hydraulic Machinery and Systems are to improve

  19. Hydraulic fracture model comparison study: Complete results

    SciTech Connect

    Warpinski, N.R.; Abou-Sayed, I.S.; Moschovidis, Z.; Parker, C.

    1993-02-01

    Large quantities of natural gas exist in low permeability reservoirs throughout the US. Characteristics of these reservoirs, however, make production difficult and often economic and stimulation is required. Because of the diversity of application, hydraulic fracture design models must be able to account for widely varying rock properties, reservoir properties, in situ stresses, fracturing fluids, and proppant loads. As a result, fracture simulation has emerged as a highly complex endeavor that must be able to describe many different physical processes. The objective of this study was to develop a comparative study of hydraulic-fracture simulators in order to provide stimulation engineers with the necessary information to make rational decisions on the type of models most suited for their needs. This report compares the fracture modeling results of twelve different simulators, some of them run in different modes for eight separate design cases. Comparisons of length, width, height, net pressure, maximum width at the wellbore, average width at the wellbore, and average width in the fracture have been made, both for the final geometry and as a function of time. For the models in this study, differences in fracture length, height and width are often greater than a factor of two. In addition, several comparisons of the same model with different options show a large variability in model output depending upon the options chosen. Two comparisons were made of the same model run by different companies; in both cases the agreement was good. 41 refs., 54 figs., 83 tabs.

  20. Research on One Borehole Hydraulic Coal Mining System

    NASA Astrophysics Data System (ADS)

    XIA, Bairu; ZENG, Xiping; MAO, Zhixin

    The Borehole Hydraulic Coal Mining System (BHCMS) causes fragmentation of coal seams and removes coal slump through a drilled hole using high-pressure water jet. Then the mixture of coal and water as slurry are driven out of the borehole by hydraulic or air-lifting method, and are separated at the surface. This paper presents a case study of hydraulic borehole coal mining. The three key techniques of the BHCMS, namely, hydraulic lift of jet pump, air lift, and water jet disintegration are discussed and analyzed in this paper based on theoretical analysis and field experiments. Some useful findings have been obtained: (1) The design of jet pump, air lift system, and water jet has to be integrated appropriately in order to improve mining efficiency and coal recovery rate, and to decrease energy consumption. The design of hydraulic lift jet pump must meet the requirement of the minimum floating speed of coal particles. The optimization of nondimensional parameters and prevention of cavitation have to be considered in the design; (2) With regard to selecting the nozzle types of jet pump, center nozzle or annular nozzle can be selected according to the size of the removed particles; (3) Through air-lift and back pressure, the water head can be decreased to improve the lift capacity of jet pump and decrease the power loss. The air lift has great limitation if it is used solely to extract coal, but if it is employed in conjunction with jet pump, the lift capacity of jet pump can be increased greatly; (4) With water jets, the air lift can improve the fragmentation radius and capacity. The main factors that affect the effect of water jet are the submergible status of jet, jet pressure, and flowrate. The ideal jet of the monitor in the borehole hydraulic coal-mining system is a nonsubmergible free jet. Through air lift, the nonsubmergible free jet can be set up in the mining hole.

  1. 14 CFR 33.72 - Hydraulic actuating systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Hydraulic actuating systems. 33.72 Section 33.72 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.72...

  2. 14 CFR 33.72 - Hydraulic actuating systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Hydraulic actuating systems. 33.72 Section 33.72 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.72...

  3. 14 CFR 33.72 - Hydraulic actuating systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Hydraulic actuating systems. 33.72 Section 33.72 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.72...

  4. 14 CFR 33.72 - Hydraulic actuating systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Hydraulic actuating systems. 33.72 Section 33.72 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.72...

  5. A synergistic approach to the design, fabrication and evaluation of 3D printed micro and nano featured scaffolds for vascularized bone tissue repair

    NASA Astrophysics Data System (ADS)

    Holmes, Benjamin; Bulusu, Kartik; Plesniak, Michael; Zhang, Lijie Grace

    2016-02-01

    3D bioprinting has begun to show great promise in advancing the development of functional tissue/organ replacements. However, to realize the true potential of 3D bioprinted tissues for clinical use requires the fabrication of an interconnected and effective vascular network. Solving this challenge is critical, as human tissue relies on an adequate network of blood vessels to transport oxygen, nutrients, other chemicals, biological factors and waste, in and out of the tissue. Here, we have successfully designed and printed a series of novel 3D bone scaffolds with both bone formation supporting structures and highly interconnected 3D microvascular mimicking channels, for efficient and enhanced osteogenic bone regeneration as well as vascular cell growth. Using a chemical functionalization process, we have conjugated our samples with nano hydroxyapatite (nHA), for the creation of novel micro and nano featured devices for vascularized bone growth. We evaluated our scaffolds with mechanical testing, hydrodynamic measurements and in vitro human mesenchymal stem cell (hMSC) adhesion (4 h), proliferation (1, 3 and 5 d) and osteogenic differentiation (1, 2 and 3 weeks). These tests confirmed bone-like physical properties and vascular-like flow profiles, as well as demonstrated enhanced hMSC adhesion, proliferation and osteogenic differentiation. Additional in vitro experiments with human umbilical vein endothelial cells also demonstrated improved vascular cell growth, migration and organization on micro-nano featured scaffolds.

  6. A synergistic approach to the design, fabrication and evaluation of 3D printed micro and nano featured scaffolds for vascularized bone tissue repair.

    PubMed

    Holmes, Benjamin; Bulusu, Kartik; Plesniak, Michael; Zhang, Lijie Grace

    2016-02-12

    3D bioprinting has begun to show great promise in advancing the development of functional tissue/organ replacements. However, to realize the true potential of 3D bioprinted tissues for clinical use requires the fabrication of an interconnected and effective vascular network. Solving this challenge is critical, as human tissue relies on an adequate network of blood vessels to transport oxygen, nutrients, other chemicals, biological factors and waste, in and out of the tissue. Here, we have successfully designed and printed a series of novel 3D bone scaffolds with both bone formation supporting structures and highly interconnected 3D microvascular mimicking channels, for efficient and enhanced osteogenic bone regeneration as well as vascular cell growth. Using a chemical functionalization process, we have conjugated our samples with nano hydroxyapatite (nHA), for the creation of novel micro and nano featured devices for vascularized bone growth. We evaluated our scaffolds with mechanical testing, hydrodynamic measurements and in vitro human mesenchymal stem cell (hMSC) adhesion (4 h), proliferation (1, 3 and 5 d) and osteogenic differentiation (1, 2 and 3 weeks). These tests confirmed bone-like physical properties and vascular-like flow profiles, as well as demonstrated enhanced hMSC adhesion, proliferation and osteogenic differentiation. Additional in vitro experiments with human umbilical vein endothelial cells also demonstrated improved vascular cell growth, migration and organization on micro-nano featured scaffolds. PMID:26758780

  7. Borehole Heat Exchanger Systems: Hydraulic Conductivity and Frost-Resistance of Backfill Materials

    NASA Astrophysics Data System (ADS)

    Anbergen, Hauke; Sass, Ingo

    2016-04-01

    Ground source heat pump (GSHP) systems are economic solutions for both, domestic heating energy supply, as well as underground thermal energy storage (UTES). Over the past decades the technology developed to complex, advanced and highly efficient systems. For an efficient operation of the most common type of UTES, borehole heat exchanger (BHE) systems, it is necessary to design the system for a wide range of carrier fluid temperatures. During heat extraction, a cooled carrier fluid is heated up by geothermal energy. This collected thermal energy is energetically used by the heat pump. Thereby the carrier fluid temperature must have a lower temperature than the surrounding underground in order to collect heat energy. The steeper the thermal gradient, the more energy is transferred to the carrier fluid. The heat injection case works vice versa. For fast and sufficient heat extraction, even over long periods of heating (winter), it might become necessary to run the BHE with fluid temperatures below 0°C. As the heat pump runs periodically, a cyclic freezing of the pore water and corresponding ice-lens growth in the nearfield of the BHE pipes becomes possible. These so called freeze-thaw-cycles (FTC) are a critical state for the backfill material, as the sealing effect eventually decreases. From a hydrogeological point of view the vertical sealing of the BHE needs to be secured at any time (e.g. VDI 4640-2, Draft 2015). The vertical hydraulic conductivity of the BHE is influenced not only by the permeability of the grouting material itself, but by the contact area between BHE pipes and grout. In order to assess the sealing capacity of grouting materials a laboratory testing procedure was developed that measures the vertical hydraulic conductivity of the system BHE pipe and grout. The key features of the procedure are: • assessment of the systeḿs hydraulic conductivity • assessment of the systeḿs hydraulic conductivity after simulation of freeze-thaw-cycle

  8. Trouble-free hydraulic valve package for crane winches

    SciTech Connect

    DeLamatyr, G.

    1983-12-01

    Baker Marine Corporation has been producing hydraulically powered pedestal type cranes for the offshore industry for approximately three years. The original hydraulic system cranes was of the open loop type with multiple gear pumps driven by a single diesel engine. One pump in the stack serviced the main and auxiliary hook winches, while another worked the boom winch, and a third pump sent oil to the crane swing motor. For reasons of economy and simplicity, it was decided that this scheme would be kept as part of the new design.

  9. Manual or hydraulic gearshifting apparatus

    SciTech Connect

    Ishida, H.; Kojima, Y.

    1986-04-08

    A vehicle transmission control apparatus is described which consists of: a plurality of shift members for operating a vehicle transmission; a lever adapted for linear movement into a plurality of positions, one each of the lever being operatively coupled to a different one of the shift members in each of the positions; the lever being further adapted for pivotal movement in response to which the one end of the lever actuates the operatively coupled shift member; a select actuator means comprising a select hydraulic cylinder and a select piston retained thereby, the select piston being coupled to the lever and hydraulically controlled to produce the linear movement thereof; a shift actuator means comprising a shift hydraulic cylinder and a shift piston retained thereby, the shift piston being coupled to the lever and hydraulically controlled to produce the pivotal movement thereof; a casing means retaining the lever, the select actuator means, and the shift actuator means; and a control member comprising a portion within the casing means and coupled to the lever and a manually accessible portion always disposed outside the casing means and having means adapted for manual actuation to produce either the linear or the pivotal movement of the lever.

  10. Tubing Cutter is Activated Hydraulically

    NASA Technical Reports Server (NTRS)

    Mcsmith, D. G.; Richardson, J. I.

    1983-01-01

    Hydraulically-actuated tubing cutter severs tubing when operator squeezes handle grip. "Gooseneck" extension enables cutter to be used in areas where accessiblity is limited. Cutter has potential as flight-line tool and is useful in automobile and fire rescue work.

  11. Hydraulic Properties of Unsaturated Soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many agrophysical applications require knowledge of the hydraulic properties of unsaturated soils. These properties reflect the ability of a soil to retain or transmit water and its dissolved constituents. The objective of this work was to develop an entry for the Encyclopedia of Agrophysics that w...

  12. Introduction to Hydraulics. Instructor's Guide.

    ERIC Educational Resources Information Center

    Texas Univ., Austin. Extension Instruction and Materials Center.

    This instructor's guide on hydraulics is part of a series of individualized instructional materials. The guide is provided to help the instructor make certain that each student gets the most benefit possible from both the student's manual and what he/she does on the job. Notes for the instructor contain suggestions on how the student should use…

  13. Tree Hydraulics: How Sap Rises

    ERIC Educational Resources Information Center

    Denny, Mark

    2012-01-01

    Trees transport water from roots to crown--a height that can exceed 100 m. The physics of tree hydraulics can be conveyed with simple fluid dynamics based upon the Hagen-Poiseuille equation and Murray's law. Here the conduit structure is modelled as conical pipes and as branching pipes. The force required to lift sap is generated mostly by…

  14. Thermal-Hydraulic-Analysis Program

    NASA Technical Reports Server (NTRS)

    Walton, J. T.

    1993-01-01

    ELM computer program is simple computational tool for modeling steady-state thermal hydraulics of flows of propellants through fuel-element-coolant channels in nuclear thermal rockets. Evaluates various heat-transfer-coefficient and friction-factor correlations available for turbulent pipe flow with addition of heat. Comparisons possible within one program. Machine-independent program written in FORTRAN 77.

  15. Downstream Hydraulic Geometry of Mountain Rivers

    NASA Astrophysics Data System (ADS)

    Wohl, E.

    2003-12-01

    The concept of downstream hydraulic geometry (DHG) was developed for fully alluvial rivers that are presumed to be capable of continually adjusting their dimensions to changes in bankfull discharge. Mountain rivers, although mostly formed in alluvium, may behave differently because discharges along the channel lack the competence to move coarse clasts introduced from colluvial processes or glaciation, or because discontinuous bedrock exposures limit channel adjustment. Consequently, the DHG of mountain rivers could reflect bankfull flows; larger magnitude, less frequent flows; or non-fluvial processes such as debris flows. The research summarized here was designed to test whether traditional DHG concepts apply to mountain rivers, and to determine when correlations between velocity, flow depth, or width, and bankfull discharge, are strongly developed. Rivers with strongly developed DHG are defined here as those with r2 values > 0.5 for at least two of the correlations. I hypothesize that a quantifiable threshold separates mountain rivers with well-developed DHG from those with poorly-developed DHG. This threshold can be expressed using a ratio of hydraulic driving forces to substrate resisting forces. As the ratio increases, the ability of bankfull flows to adjust channel dimensions should also increase. The hypothesis was tested using 8 datasets from mountain rivers in Alaska, Montana, Colorado, Panama, Nepal, and New Zealand. A ratio of either total stream power/D84, or unit stream power/D84, separates rivers with and without well-developed DHG. This approach is a simplification which ignores the presence of bedrock; the duration and frequency of flows as these affect stream power; and non-fluvial processes. However, the results suggest that mountain rivers with greater hydraulic driving forces are more likely to behave like fully alluvial rivers in terms of having well-developed DHG relations.

  16. CRITICALITY CURVES FOR PLUTONIUM HYDRAULIC FLUID MIXTURES

    SciTech Connect

    WITTEKIND WD

    2007-10-03

    This Calculation Note performs and documents MCNP criticality calculations for plutonium (100% {sup 239}Pu) hydraulic fluid mixtures. Spherical geometry was used for these generalized criticality safety calculations and three geometries of neutron reflection are: {sm_bullet}bare, {sm_bullet}1 inch of hydraulic fluid, or {sm_bullet}12 inches of hydraulic fluid. This document shows the critical volume and critical mass for various concentrations of plutonium in hydraulic fluid. Between 1 and 2 gallons of hydraulic fluid were discovered in the bottom of HA-23S. This HA-23S hydraulic fluid was reported by engineering to be Fyrquel 220. The hydraulic fluid in GLovebox HA-23S is Fyrquel 220 which contains phosphorus. Critical spherical geometry in air is calculated with 0 in., 1 in., or 12 inches hydraulic fluid reflection.

  17. HYDRAULIC CHARACTERISTICS OF ACTIVATED SLUDGE SECONDARY CLARIFIERS

    EPA Science Inventory

    This study documented the hydraulic characteristics of typical activated sludge clarifiers. Modifications to the clarifier structures were made in an attempt to improve clarifier hydraulic characteristics and performance. Innovative fluorometric dye tracer studies were used to ob...

  18. Investigation of hydraulic transmission noise sources

    NASA Astrophysics Data System (ADS)

    Klop, Richard J.

    Advanced hydrostatic transmissions and hydraulic hybrids show potential in new market segments such as commercial vehicles and passenger cars. Such new applications regard low noise generation as a high priority, thus, demanding new quiet hydrostatic transmission designs. In this thesis, the aim is to investigate noise sources of hydrostatic transmissions to discover strategies for designing compact and quiet solutions. A model has been developed to capture the interaction of a pump and motor working in a hydrostatic transmission and to predict overall noise sources. This model allows a designer to compare noise sources for various configurations and to design compact and inherently quiet solutions. The model describes dynamics of the system by coupling lumped parameter pump and motor models with a one-dimensional unsteady compressible transmission line model. The model has been verified with dynamic pressure measurements in the line over a wide operating range for several system structures. Simulation studies were performed illustrating sensitivities of several design variables and the potential of the model to design transmissions with minimal noise sources. A semi-anechoic chamber has been designed and constructed suitable for sound intensity measurements that can be used to derive sound power. Measurements proved the potential to reduce audible noise by predicting and reducing both noise sources. Sound power measurements were conducted on a series hybrid transmission test bench to validate the model and compare predicted noise sources with sound power.

  19. LMR thermal hydraulics calculations in the US

    SciTech Connect

    Dunn, F.E.; Malloy, D.J.; Mohr, D.

    1987-04-27

    A wide range of thermal hydraulics computer codes have been developed by various organizations in the US. These codes cover an extensive range of purposes from within-assembly-wise pin temperature calculations to plant wide transient analysis. The codes are used for static analysis, for analysis of protected anticipated transients, and for analysis of a wide range of unprotected transients for the more recent inherently safe LMR designs. Some of these codes are plant-specific codes with properties of a specific plant built into them. Other codes are more general and can be applied to a number of plants or designs. These codes, and the purposes for which they have been used, are described.

  20. Dewatering of coalbed methane wells with hydraulic gas pump

    SciTech Connect

    Amani, M.; Juvkam-Wold, H.C.

    1995-12-31

    The coalbed methane industry has become an important source of natural gas production. Proper dewatering of coalbed methane (CBM) wells is the key to efficient gas production from these reservoirs. This paper presents the Hydraulic Gas Pump as a new alternative dewatering system for CBM wells. The Hydraulic Gas Pump (HGP) concept offers several operational advantages for CBM wells. Gas interference does not affect its operation. It resists solids damage by eliminating the lift mechanism and reducing the number of moving parts. The HGP has a flexible production rate and is suitable for all production phases of CBM wells. It can also be designed as a wireline retrievable system. We conclude that the Hydraulic Gas Pump is a suitable dewatering system for coalbed methane wells.