These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Miners lamp power pack  

SciTech Connect

A lamp rechargeable dry cell power pack and recharging device therefor is disclosed. The recharging device comprises a socket for receiving the power pack, a plurality of electrodes are presented in the socket and arranged to contact corresponding electrodes on the power pack when it is fully inserted in the socket. The power pack is irregular shaped in cross-section and the socket is correspondingly shaped to receive and support the power pack in only one orientation of the power pack relative to the socket to ensure the registration of the plurality of socket electrodes with corresponding power pack electrodes.

Lane, K.S.

1984-11-06

2

Hydraulically refueled battery employing a packed bed metal particle electrode  

DOEpatents

A secondary zinc air cell, or another selected metal air cell, employing a spouted/packed metal particle bed and an air electrode. More specifically, two embodiments of a cell, one that is capable of being hydraulically recharged, and a second that is capable of being either hydraulically or electrically recharged. Additionally, each cell includes a sloped bottom portion to cause stirring of the electrolyte/metal particulate slurry when the cell is being hydraulically emptied and refilled during hydraulically recharging of the cell.

Siu, Stanley C. (Castro Valley, CA); Evans, James W. (Piedmont, CA)

1998-01-01

3

Hydraulically refueled battery employing a packed bed metal particle electrode  

DOEpatents

A secondary zinc air cell, or another selected metal air cell, employing a spouted/packed metal particle bed and an air electrode is described. More specifically, two embodiments of a cell, one that is capable of being hydraulically recharged, and a second that is capable of being either hydraulically or electrically recharged. Additionally, each cell includes a sloped bottom portion to cause stirring of the electrolyte/metal particulate slurry when the cell is being hydraulically emptied and refilled during hydraulically recharging of the cell. 15 figs.

Siu, S.C.; Evans, J.W.

1998-12-15

4

Recover Power with Hydraulic Motors  

E-print Network

Anywhere liquid pressure is reduced across a throttling device, there is a potential application for a hydraulic power recovery motor (HPRM). Cost of power makes HPRM's attractive with recoveries as small as 25 hp on a continuous basis. When...

Brennan, J. R.

1982-01-01

5

Fluid Power/Basic Hydraulics. Instructor's Guide.  

ERIC Educational Resources Information Center

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…

Stanbery, Richard

6

Power Consumption Prediction and Power-Aware Packing in Consolidated  

E-print Network

Power Consumption Prediction and Power-Aware Packing in Consolidated Environments Jeonghwan Choi the power consumption of groups of colocated applications. Such characterization is crucial for effective prediction and enforcement of appropriate limits on power consumption--power budgets--within the data center

Urgaonkar, Bhuvan

7

Gas-to-hydraulic power converter  

NASA Technical Reports Server (NTRS)

A gas piston driven hydraulic piston pump is described in which the gas cycle is of high efficiency by injecting the gas in slugs at the beginning of each power stroke. The hydraulic piston is disposed to operate inside the as piston, and the two pistons, both slidably but nonrotatably mounted, are coupled together with a rotating but non-sliding motion transfer ring extending into antifriction grooves in the sidewalls of the two pistons. To make the hydraulic piston move at a constant speed during constant hydraulic horsepower demand and thus exert a constant pressure on the hydraulic fluid, these grooves are machined with variable pitches and one is the opposite of the other, i.e., the gas piston groove increases in pitch during its power stroke while the hydraulic piston groove decreases. Any number of piston assembly sets may be used to obtain desired hydraulic horsepower.

Galloway, C. W. (inventor)

1982-01-01

8

Gas-to-hydraulic power converter  

NASA Astrophysics Data System (ADS)

A gas piston driven hydraulic piston pump is described in which the gas cycle is of high efficiency by injecting the gas in slugs at the beginning of each power stroke. The hydraulic piston is disposed to operate inside the as piston, and the two pistons, both slidably but nonrotatably mounted, are coupled together with a rotating but non-sliding motion transfer ring extending into antifriction grooves in the sidewalls of the two pistons. To make the hydraulic piston move at a constant speed during constant hydraulic horsepower demand and thus exert a constant pressure on the hydraulic fluid, these grooves are machined with variable pitches and one is the opposite of the other, i.e., the gas piston groove increases in pitch during its power stroke while the hydraulic piston groove decreases. Any number of piston assembly sets may be used to obtain desired hydraulic horsepower.

Galloway, C. W.

1981-02-01

9

Space Shuttle Upgrades Advanced Hydraulic Power System  

NASA Technical Reports Server (NTRS)

Three Auxiliary Power Units (APU) on the Space Shuttle Orbiter each provide 145 hp shaft power to a hydraulic pump which outputs 3000 psi hydraulic fluid to 41 hydraulic actuators. A hydrazine fuel powered APU utilized throughout the Shuttle program has undergone many improvements, but concerns remain with flight safety, operational cost, critical failure modes, and hydrazine related hazards. The advanced hydraulic power system (AHPS), also known as the electric APU, is being evaluated as an upgrade to replace the hydrazine APU. The AHPS replaces the high-speed turbine and hydrazine fuel supply system with a battery power supply and electric motor/pump that converts 300 volt electrical power to 3000 psi hydraulic power. AHPS upgrade benefits include elimination of toxic hydrazine propellant to improve flight safety, reduction in hazardous ground processing operations, and improved reliability. Development of this upgrade provides many interesting challenges and includes development of four hardware elements that comprise the AHPS system: Battery - The battery provides a high voltage supply of power using lithium ion cells. This is a large battery that must provide 28 kilowatt hours of energy over 99 minutes of operation at 300 volts with a peak power of 130 kilowatts for three seconds. High Voltage Power Distribution and Control (PD&C) - The PD&C distributes electric power from the battery to the EHDU. This 300 volt system includes wiring and components necessary to distribute power and provide fault current protection. Electro-Hydraulic Drive Unit (EHDU) - The EHDU converts electric input power to hydraulic output power. The EHDU must provide over 90 kilowatts of stable, output hydraulic power at 3000 psi with high efficiency and rapid response time. Cooling System - The cooling system provides thermal control of the Orbiter hydraulic fluid and EHDU electronic components. Symposium presentation will provide an overview of the AHPS upgrade, descriptions of the four hardware elements, and a summary of development results to date.

2004-01-01

10

Hydraulically powered dissimilar teleoperated system controller design  

SciTech Connect

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.

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

1996-04-01

11

Centre Hydraulic Power Supply Unit University of Saskatchewan -Mechanical Engineering Fluid Power and Controls  

E-print Network

Centre Hydraulic Power Supply Unit University of Saskatchewan - Mechanical Engineering ­ Fluid Power and Controls ID: FP0003 Rev: 001 Date: May 31, 2010 Page: 1 of 7 Centre Hydraulic Power Supply;Centre Hydraulic Power Supply Unit University of Saskatchewan - Mechanical Engineering ­ Fluid Power

Saskatchewan, University of

12

HYPower Hydraulic Power Supply Unit University of Saskatchewan -Mechanical Engineering Fluid Power and Controls  

E-print Network

HYPower Hydraulic Power Supply Unit University of Saskatchewan - Mechanical Engineering ­ Fluid Power and Controls ID: FP0002 Rev: 002 Date: May 31, 2010 Page: 1 of 7 Hydraulic Power Supply (HYPower-5462 Secondary Contact: #12;HYPower Hydraulic Power Supply Unit University of Saskatchewan - Mechanical

Saskatchewan, University of

13

East Hydraulic Power Supply Unit University of Saskatchewan -Mechanical Engineering Fluid Power and Controls  

E-print Network

East Hydraulic Power Supply Unit University of Saskatchewan - Mechanical Engineering ­ Fluid Power and Controls ID: FP0004 Rev: 001 Date: May 31, 2010 Page: 1 of 7 East Hydraulic Power Supply and Test Bench. Approved By: Primary Contact: Doug Bitner Rm: 1B15.1 966-5462 Secondary Contact: #12;East Hydraulic Power

Saskatchewan, University of

14

Hydraulic power unit for measurement while drilling apparatus  

Microsoft Academic Search

A hydraulic power unit is provided for a downhole instrument of a measurement while drilling system for a well drilling. The hydraulic power unit is enclosed within a drill collar that is connected in the drill string of a rotary drilling rig. An outer body sleeve is rigidly mounted in the instrument drill collar. A fixed inner sleeve is connected

J. M. Peppers; F. A. Shaikh

1984-01-01

15

49 CFR 173.172 - Aircraft hydraulic power unit fuel tank.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 false Aircraft hydraulic power unit fuel...PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT...and Class 7 § 173.172 Aircraft hydraulic power unit fuel tank. Aircraft hydraulic power unit...

2014-10-01

16

Control issues for a hydraulically powered dissimilar teleoperated system  

SciTech Connect

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.)

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

1995-12-31

17

Power-law friction in closely-packed granular materials  

E-print Network

In order to understand the nature of friction in closely-packed granular materials, a discrete element simulation on granular layers subjected to isobaric plain shear is performed. It is found that the friction coefficient increases as the power of the shear rate, the exponent of which does not depend on the material constants. Using a nondimensional parameter that is known as the inertial number, the power-law can be cast in a generalized form so that the friction coefficients at different confining pressures collapse on the same curve. We show that the volume fraction also obeys a power-law.

Takahiro Hatano

2007-05-08

18

Hydraulics.  

ERIC Educational Resources Information Center

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)…

Decker, Robert L.; Kirby, Klane

19

46 CFR 111.97-5 - Electric and hydraulic power supply.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Electric and hydraulic power supply. 111.97-5 Section 111...SYSTEMS-GENERAL REQUIREMENTS Electric Power-Operated Watertight Door Systems § 111.97-5 Electric and hydraulic power supply. (a) Each electric...

2013-10-01

20

46 CFR 111.97-5 - Electric and hydraulic power supply.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Electric and hydraulic power supply. 111.97-5 Section 111...SYSTEMS-GENERAL REQUIREMENTS Electric Power-Operated Watertight Door Systems § 111.97-5 Electric and hydraulic power supply. (a) Each electric...

2011-10-01

21

46 CFR 111.97-5 - Electric and hydraulic power supply.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Electric and hydraulic power supply. 111.97-5 Section 111...SYSTEMS-GENERAL REQUIREMENTS Electric Power-Operated Watertight Door Systems § 111.97-5 Electric and hydraulic power supply. (a) Each electric...

2012-10-01

22

Adaptive mode switch of intelligent hydraulic power supply system  

Microsoft Academic Search

Replacing constant pressure variable flow pumps with intelligent pumps is the most effective approach to improve the efficiency of high pressure & high power aircraft hydraulic system. The crux of the matter is to regulate the output variables of pumps to meet system requirement via actively controlling the swash plate angle. This paper analyzes a typical flight profile to develop

Bochao Huang; Shaoping Wang

2011-01-01

23

Hydraulics.  

ERIC Educational Resources Information Center

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…

Engelbrecht, Nancy; And Others

24

49 CFR 173.172 - Aircraft hydraulic power unit fuel tank.  

Code of Federal Regulations, 2010 CFR

...hydraulic power unit fuel tank. Aircraft hydraulic power unit fuel tanks containing a mixture of anhydrous hydrazine and monomethyl hydrazine (M86 fuel) and designed for installation as complete units in aircraft are excepted from the...

2010-10-01

25

Nonlinear State Space Model of a Hydraulic Wind Power Transfer Masoud Vaezi1  

E-print Network

Nonlinear State Space Model of a Hydraulic Wind Power Transfer Masoud Vaezi1 , Majid Deldar1 1, IUPUI. Gearless hydraulic wind power systems are considered as nonlinear models because of some discrete nonlinear governing equations for the elements in the proposed hydraulic wind power configuration. Nonlinear

Zhou, Yaoqi

26

A NEW PASSIVE CONTROLLER FOR A HYDRAULIC HUMAN POWER AMPLIFIER Perry Y. Li  

E-print Network

A NEW PASSIVE CONTROLLER FOR A HYDRAULIC HUMAN POWER AMPLIFIER Perry Y. Li Department of Mechanical A new, intrinsically passive controller for hydraulic human power amplifier is presented. The hydraulic that humans manipulate directly, but have the ability to attenuate or amplify the apparent power

Li, Perry Y.

27

Hydraulics.  

ERIC Educational Resources Information Center

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,…

Decker, Robert L.

28

46 CFR 111.97-5 - Electric and hydraulic power supply.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Electric and hydraulic power supply. 111.97-5 Section...Systems § 111.97-5 Electric and hydraulic power supply. (a) Each electric...operated watertight door system that uses a hydraulic system common to more than one...

2010-10-01

29

Coupled Monte Carlo neutronics and thermal hydraulics for power reactors  

SciTech Connect

The availability of high performance computing resources enables more and more the use of detailed Monte Carlo models even for full core power reactors. The detailed structure of the core can be described by lattices, modeled by so-called repeated structures e.g. in Monte Carlo codes such as MCNP5 or MCNPX. For cores with mainly uniform material compositions, fuel and moderator temperatures, there is no problem in constructing core models. However, when the material composition and the temperatures vary strongly a huge number of different material cells must be described which complicate the input and in many cases exceed code or memory limits. The second problem arises with the preparation of corresponding temperature dependent cross sections and thermal scattering laws. Only if these problems can be solved, a realistic coupling of Monte Carlo neutronics with an appropriate thermal-hydraulics model is possible. In this paper a method for the treatment of detailed material and temperature distributions in MCNP5 is described based on user-specified internal functions which assign distinct elements of the core cells to material specifications (e.g. water density) and temperatures from a thermal-hydraulics code. The core grid itself can be described with a uniform material specification. The temperature dependency of cross sections and thermal neutron scattering laws is taken into account by interpolation, requiring only a limited number of data sets generated for different temperatures. Applications will be shown for the stationary part of the Purdue PWR benchmark using ATHLET for thermal- hydraulics and for a generic Modular High Temperature reactor using THERMIX for thermal- hydraulics. (authors)

Bernnat, W.; Buck, M.; Mattes, M. [Institut fuer Kernenergetik und Energiesysteme IKE, Universitaet Stuttgart, Pfaffenwaldring 31, D-70569 Stuttgart (Germany); Zwermann, W.; Pasichnyk, I.; Velkov, K. [Gesellschaft fuer Anlagen- und Reaktorsicherheit GRS MbH, Forschungszentrum, Boltzmannstrase 14, 85748 Garching (Germany)

2012-07-01

30

Hydraulics  

NSDL National Science Digital Library

These interactive learning objects, created by instructors from Fox Valley Technical College and other colleges in the Wisconsin Technical College program, focus on concepts that cover a broad-based electromechanical program. Here visitors will find learning objects in Hydraulics with over 25 lessons in Actuators, Relief Valves, Basic Concepts, and Directional Control Valves.

31

Optimal Design of Power-Split Transmissions for Hydraulic Hybrid Passenger Vehicles  

E-print Network

Optimal Design of Power-Split Transmissions for Hydraulic Hybrid Passenger Vehicles Kai Loon Cheong, Perry Y. Li and Thomas R. Chase Abstract-- Hydraulic hybrid vehicles are inherently power dense. Power-split or hydro-mechanical transmissions (HMT) have advantages over series and parallel architectures

Li, Perry Y.

32

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

Code of Federal Regulations, 2012 CFR

...pneumatic power and control-materials and pressure design. 128.240 Section 128...EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard...

2012-10-01

33

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

Code of Federal Regulations, 2013 CFR

...pneumatic power and control-materials and pressure design. 128.240 Section 128...EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard...

2013-10-01

34

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

Code of Federal Regulations, 2010 CFR

...pneumatic power and control-materials and pressure design. 128.240 Section 128...EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard...

2010-10-01

35

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

Code of Federal Regulations, 2014 CFR

...pneumatic power and control-materials and pressure design. 128.240 Section 128...EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard...

2014-10-01

36

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

Code of Federal Regulations, 2011 CFR

...pneumatic power and control-materials and pressure design. 128.240 Section 128...EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.240 Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard...

2011-10-01

37

Power Plays: Proven Methods of Professional Learning Pack a Force  

ERIC Educational Resources Information Center

Powerful professional learning is more than a one-shot workshop. It involves educators working collegially on a matter they care about with content arising directly from their classroom experiences. Educators know which strategies offer more powerful learning. Choosing the appropriate strategy requires answering just three questions.

Easton, Lois Brown

2005-01-01

38

Development and testing of a hydraulic powered diver operated rock drill and sea floor fasteners  

Microsoft Academic Search

The Civil Engineering Laboratory has developed a hand held diver operated rock drill. The drill is hydraulically powered thus eliminating the percussion and visibility problems associated with the underwater use of pneumatic rock drills. Capable of drilling holes up to 2-1\\/2 inches in diameter and 18 inches deep, the hydraulic rock drill has been used to install various seafloor fasteners

R. Brackett

1975-01-01

39

Power management for multi-actuator mobile machines with displacement controlled hydraulic actuators  

Microsoft Academic Search

Economic and environmental factors provide the motivation for a continuing trend toward more energy efficient fluid power systems in construction and agricultural machinery. One of the energy-efficient alternatives to today's valve-controlled hydraulic systems is displacement controlled (DC) actuation, in which hydraulic cylinders and motors are controlled directly by variable displacement pumps. ^ The primary contribution of this thesis is a

Christopher A Williamson

2010-01-01

40

Haptic-enabled control of hydraulic manipulators applied to power line maintenance: Concept & implementation  

Microsoft Academic Search

In this paper, we present development of a scheme enabling a commercially available hydraulic robot to work with a haptic device performing live-line maintenance tasks. Presently live line maintenance is done manually by operators working in locations high above the ground and near high voltage power lines. Ground-level teleoperation of a hydraulic manipulator using a haptic device can potentially increase

K. Zarei-nia; N. Sepehri; T. Olson; W. Mueller

2010-01-01

41

A study on hydraulic buffering valve dynamic performance simulation of vehicular power shift transmission  

Microsoft Academic Search

Adopting a hydraulic buffering valve is an effective means to get good shift quality. Dynamic performance analysis of the buffering valve has been an indispensable link of design work. In this paper, a dynamic simulation model of a hydraulic buffering valve for a vehicle power shift clutch has been developed, simulation study was made by SIMULINK of MATLAB and dynamic

Biao Ma; Ying Liu; Ming Ye

1999-01-01

42

Design and analysis of a thermal hydraulic integral test facility for Bushehr nuclear power plant  

Microsoft Academic Search

In this paper, design and analysis of a thermal hydraulic integral test facility for Bushehr Nuclear Power Plant (NPP) is presented. The Bushehr Integral Test Facility (BITF) is a test facility designed to model the thermal-hydraulic behaviours of the Bushehr NPP (VVER-1000) pressurized water reactors currently in use in IRAN. These reactors have unique features that differ from other PWR

Toraj Khoshnevis; Jalil Jafari; Mostafa Sohrabpour

2009-01-01

43

An Integrated Power Pack of Dye-Sensitized Solar Cell and Li Battery Based on Double-Sided TiO2 Nanotube Arrays  

E-print Network

An Integrated Power Pack of Dye-Sensitized Solar Cell and Li Battery Based on Double-Sided TiO2 harvest and storage processes. This power pack incorporates a series-wound dye- sensitized solar cell and storage efficiency for this system is 0.82%. Such an integrated power pack could serve as a power source

Wang, Zhong L.

44

NEUTRONIC AND THERMAL HYDRAULIC DESIGNS OF ANNULAR FUEL FOR HIGH POWER DENSITY BWRS  

E-print Network

As a promising new fuel for high power density light water reactors, the feasibility of using annular fuel for BWR services is explored from both thermal hydraulic and neutronic points of view. Keeping the bundle size ...

Morra, P.

45

Portable ammonia-borane-based H2 power-pack for unmanned aerial vehicles  

NASA Astrophysics Data System (ADS)

An advanced ammonia borane (AB)-based H2 power-pack is designed to continually drive an unmanned aerial vehicle (UAV) for 57 min using a 200-We polymer electrolyte membrane fuel cell (PEMFC). In a flight test with the UAV platform integrated with the developed power-pack, pure hydrogen with an average flow rate of 3.8 L(H2) min-1 is generated by autothermal H2-release from AB with tetraethylene glycol dimethylether (T4EGDE) as a promoter. During take-off, a hybridized power management system (PMS) consisting of the fuel cell and an auxiliary lithium-ion battery supplies 500 We at full power simultaneously, while the fuel cell alone provides 150-200 We and further recharges the auxiliary battery upon cruising. Gaseous byproducts identified by in situ Fourier transform infrared (FT-IR) spectroscopy during AB dehydrogenation are sequestrated using a mixed absorbent in an H2 purification system. In addition, a real-time monitoring system is employed to determine the remaining filter capacity of the purifier at a ground control system for rapidly responding unpredictable circumstances during flight. Separate experiments are conducted to screen potential materials and methods for enhancing filter capacity in the current H2 refining system. A prospective reactor concept for long-term fuel cell applications is proposed based on the results.

Seo, Jung-Eun; Kim, Yujong; Kim, Yongmin; Kim, Kibeom; Lee, Jin Hee; Lee, Dae Hyung; Kim, Yeongcheon; Shin, Seock Jae; Kim, Dong-Min; Kim, Sung-Yug; Kim, Taegyu; Yoon, Chang Won; Nam, Suk Woo

2014-05-01

46

Abstract--Small-scale hydraulics is ideal for powered human assistive devices including powered ankle foot orthoses because  

E-print Network

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 Department, University of Minnesota, Minneapolis, MN 55455 USA (e-mail: wldurfee@umn.edu). leaf spring

Durfee, William K.

47

A high-power hydraulic drill for breaking hard rock  

Microsoft Academic Search

Conclusions  \\u000a \\u000a \\u000a \\u000a 1. \\u000a \\u000a Direct impact of the striker mass on the rock can greatly increase the impact energy and the efficiency of the apparatus.\\u000a \\u000a \\u000a \\u000a \\u000a 2. \\u000a \\u000a Automatic operation of the mechanism for opening the ports increases the frequency of impacts of the hydraulic drill.\\u000a \\u000a \\u000a \\u000a \\u000a 3. \\u000a \\u000a A hazardous state which can occur in the absence of obstacles to impact can be avoided by

F. F. Voitsekhovskaya

1974-01-01

48

Power generation by packed-bed air-cathode microbial fuel cells.  

PubMed

Catalysts and catalyst binders are significant portions of the cost of microbial fuel cell (MFC) cathodes. Many materials have been tested as aqueous cathodes, but air-cathodes are needed to avoid energy demands for water aeration. Packed-bed air-cathodes were constructed without expensive binders or diffusion layers using four inexpensive carbon-based materials. Cathodes made from activated carbon produced the largest maximum power density of 676 ± 93 mW/m(2), followed by semi-coke (376 ± 47 mW/m(2)), graphite (122 ± 14 mW/m(2)) and carbon felt (60 ± 43 mW/m(2)). Increasing the mass of activated carbon and semi-coke from 5 to ? 15 g significantly reduced power generation because of a reduction in oxygen transfer due to a thicker water layer in the cathode (?3 or ?6 cm). These results indicate that a thin packed layer of activated carbon or semi-coke can be used to make inexpensive air-cathodes for MFCs. PMID:23732924

Zhang, Xiaoyuan; Shi, Juan; Liang, Peng; Wei, Jincheng; Huang, Xia; Zhang, Chuanyi; Logan, Bruce E

2013-08-01

49

THE THERMAL AND HYDRAULIC CHARACTERISTICS OF POWER REACTOR FUEL BUNDLE DESIGNS  

Microsoft Academic Search

The type of fuel bundle evolved for the various Canadian heavy water-; moderated power reactors is described. The data necessary for estimating the ; thermal and hydraulic characteristics of this type of fuel bundle are indicated. ; The calculations and experimentation undertaken in the general fields of fluid ; flow, heat transfer, and coolant mixing are then described. The future

G. T. Leaist; R. D. Page; R. J. Klock

1963-01-01

50

Survey of thermal-hydraulic models of commercial nuclear power plants  

SciTech Connect

A survey of the thermal-hydraulic models of nuclear power plants has been performed to identify the NRC's current analytical capabilities for critical event response. The survey also supports ongoing research for accident management. The results of the survey are presented here. The PC database which records detailed data on each model is described.

Determan, J.C.; Hendrix, C.E.

1992-12-01

51

Survey of thermal-hydraulic models of commercial nuclear power plants  

SciTech Connect

A survey of the thermal-hydraulic models of nuclear power plants has been performed to identify the NRC`s current analytical capabilities for critical event response. The survey also supports ongoing research for accident management. The results of the survey are presented here. The PC database which records detailed data on each model is described.

Determan, J.C.; Hendrix, C.E.

1992-12-01

52

The hydraulic conductivity of chopped sorghum  

SciTech Connect

Hydraulic conductivity of water through chopped sweet sorghum at various packing densities and soaking times was measured using permeameters. Hydraulic conductivity decreased by two orders of magnitude as packing density increased from 400 to 897 kg/m/sup 3/. Soaking time had less effect on hydraulic conductivity, and the effect depended on packing density.

Custer, M.H.; Reddell, D.L.; Sweeten, J.M.

1987-01-01

53

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

NASA Astrophysics Data System (ADS)

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.

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

2013-03-01

54

On-Shore Central Hydraulic Power Generation for Wind and Tidal Energy  

NASA Technical Reports Server (NTRS)

Tidal energy, offshore wind energy, and onshore wind energy can be converted to electricity at a central ground location by means of converting their respective energies into high-pressure hydraulic flows that are transmitted to a system of generators by high-pressure pipelines. The high-pressure flows are then efficiently converted to electricity by a central power plant, and the low-pressure outlet flow is returned. The Department of Energy (DOE) is presently supporting a project led by Sunlight Photonics to demonstrate a 15 kW tidal hydraulic power generation system in the laboratory and possibly later submerged in the ocean. All gears and submerged electronics are completely eliminated. A second portion of this DOE project involves sizing and costing a 15 MW tidal energy system for a commercial tidal energy plant. For this task, Atlantis Resources Corporation s 18-m diameter demonstrated tidal blades are rated to operate in a nominal 2.6 m/sec tidal flow to produce approximately one MW per set of tidal blades. Fifteen units would be submerged in a deep tidal area, such as in Maine s Western Passage. All would be connected to a high-pressure (20 MPa, 2900 psi) line that is 35 cm ID. The high-pressure HEPG fluid flow is transported 500-m to on-shore hydraulic generators. HEPG is an environmentally-friendly, biodegradable, watermiscible fluid. Hydraulic adaptations to ORPC s cross-flow turbines are also discussed. For 15 MW of wind energy that is onshore or offshore, a gearless, high efficiency, radial piston pump can replace each set of top-mounted gear-generators. The fluid is then pumped to a central, easily serviceable generator location. Total hydraulic/electrical efficiency is 0.81 at full rated wind or tidal velocities and increases to 0.86 at 1/3 rated velocities.

Jones, Jack A.; Bruce, Allan; Lim, Steven; Murray, Luke; Armstrong, Richard; Kimbrall, Richard; Cook-Chenault, Kimberly; DeGennaro, Sean

2012-01-01

55

Vehicle having hydraulic and power steering systems using a single high pressure pump  

DOEpatents

A vehicle comprises a plurality of wheels attached to a vehicle housing. Also attached to the vehicle housing is a power steering system, including a fluid flow circuit, which is operably coupled to a number of the wheels. An internal combustion engine attached to the vehicle housing is connected to a hydraulically actuated system that includes a high pressure pump. An outlet of the high pressure pump is in fluid communication with the fluid flow circuit.

Bartley, Bradley E. (Manito, IL); Blass, James R. (Bloomington, IL); Gibson, Dennis H. (Chillicothe, IL)

2001-06-22

56

Analysis of hydraulic power transduction in regenerative rotary shock absorbers as function of working fluid kinematic viscosity  

E-print Network

This investigation seeks to investigate the relationship of kinematic fluid viscosity to the effective power transduction seen by a hydraulic motor. Applications of this research specifically relate to energy recovery from ...

Avadhany, Shakeel N

2009-01-01

57

The role of filament-packing dynamics in powering amoeboid cell motility  

PubMed Central

Although several models have been proposed to account for how cytoskeleton polymerization drives protrusion in cell motility, the precise mechanism remains controversial. Here, we show that, in addition to force exerted directly against the membrane by growing filaments, the way elongating filaments pack also contributes to protrusion by generating an expansion of the cytoskeleton gel. Tomography shows that filament packing in the major sperm protein (MSP) -based nematode sperm-motility machinery resembles that observed with rigid rods. Maximum rod-packing density decreases dramatically as the rods lengthen. Therefore, as filaments elongate, the cytoskeleton gel expands to accommodate their packing less densely. This volume expansion combines with polymerization to drive protrusion. Consistent with this hypothesis, an engineered MSP mutant that generates shorter filaments shows higher filament-packing density and slower movement. PMID:18385381

Miao, Long; Vanderlinde, Orion; Liu, Jun; Grant, Richard P.; Wouterse, Alan; Shimabukuro, Katsuya; Philipse, Albert; Stewart, Murray; Roberts, Thomas M.

2008-01-01

58

[Application of ICP-AES in automotive hydraulic power steering system fault diagnosis].  

PubMed

The authors studied the innovative applications of the inductively coupled plasma-atomic emission spectrometry in automotive hydraulic power steering system fault diagnosis. After having determined Fe, Cu and Al content in the four groups of Buick Regal 2.4 main metal power-steering fluid whose travel course was respectively 2-9 thousand kilometers, 11-18 thousand kilometers, 22-29 thousandkilometers, and 31-40 thousand kilometers, and the database of primary metal content in the Buick Regal 2.4 different mileage power-steering fluid was established. The research discovered that the main metal content increased with increasing mileage and its normal level is between the two trend lines. Determination of the power-steering fluid main metal content and comparison with its database value can not only judge the wear condition of the automotive hydraulic power steering system and maintain timely to avoid the traffic accident, but also help the automobile detection and maintenance personnel to diagnose failure reasons without disintegration. This reduced vehicle maintenance costs, and improved service quality. PMID:23586258

Chen, Li-Dan

2013-01-01

59

Hydraulic Car  

NSDL National Science Digital Library

In this activity, learners build cars using syringes and water-powered hydraulics. Learners construct the car frame out of cardboard and set up a hydraulic system to raise and lower the car. Use this project to introduce learners to incompressible fluids and Pascal's Principle.

2014-09-12

60

Thermal-hydraulics and safety analysis of sectored compact reactor for lunar surface power  

SciTech Connect

The liquid NaK-cooled, fast-neutron spectrum, Sectored Compact Reactor (SCoRe-N 5) concept has been developed at the Univ. of New Mexico for lunar surface power applications. It is loaded with highly enriched UN fuel pins in a triangular lattice, and nominally operates at exit and inlet coolant temperatures of 850 K and 900 K. This long-life reactor generates up to 1 MWth continuously for {>=} 20 years. To avoid a single point failure in reactor cooling, the core is divided into 6 sectors that are neutronically and thermally coupled, but hydraulically independent. This paper performs a 3-D the thermal-hydraulic analysis of SCoRe--N 5 at nominal operation temperatures and a power level of 1 MWth. In addition, the paper investigates the potential of continuing reactor operation at a lower power in the unlikely event that one sector in the core experiences a loss of coolant (LOC). Redesigning the core with a contiguous steel matrix enhances the cooling of the sector experiencing a LOC. Results show that with a core sector experiencing a LOC, SCORE-N 5 could continue operating safely at a reduced power of 166.6 kWth. (authors)

Schriener, T. M. [Inst. for Space and Nuclear Power Studies, Univ. of New Mexico, Albuquerque, NM (United States); Chemical and Nuclear Engineering Dept., Univ. of New Mexico, Albuquerque, NM (United States); El-Genk, M. S. [Inst. for Space and Nuclear Power Studies, Univ. of New Mexico, Albuquerque, NM (United States); Chemical and Nuclear Engineering Dept., Univ. of New Mexico, Albuquerque, NM (United States); Mechanical Engineering Dept., Univ. of New Mexico, Albuquerque, NM (United States)

2012-07-01

61

Development of a 7-function hydraulic underwater manipulator system  

Microsoft Academic Search

A 7-function underwater manipulator which is teleoperated by master-slave type is systemically developed. It is mainly comprised of master controller, connection box, slave arm, pressure compensator, valve pack and hydraulic power unit. The slave arm is operated by the master arm, which is fixed on the master controller used to operate, configure, and diagnose the manipulator system and is a

Jianjun Yao; Liquan Wang; Peng Jia; Zhuo Wang

2009-01-01

62

Numerical and field tests of hydraulic transients at Piva power plant  

NASA Astrophysics Data System (ADS)

In 2009, a sophisticated field investigation was undertaken and later, in 2011, numerical tests were completed, on all three turbine units at the Piva hydroelectric power plant. These tests were made in order to assist in making decisions about the necessary scope of the reconstruction and modernisation of the Piva hydroelectric power plant, a plant originally constructed in the mid-1970s. More specifically, the investigation included several hydraulic conditions including both the start-up and stopping of each unit, load rejection under governor control from different initial powers, as well as emergency shut-down. Numerical results were obtained using the method of characteristics in a representation that included the full flow system and the characteristics of each associated Francis turbine. The impact of load rejection and emergency shut-down on the penstock pressure and turbine speed changes are reported and numerical and experimental results are compared, showing close agreement.

Giljen, Z.

2014-12-01

63

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

SciTech Connect

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.

Krotiuk, W.J.

1990-01-01

64

Improvement of the method used for hydraulic profiling of an RBMK-1500 core at the Ignalina nuclear power plant  

Microsoft Academic Search

An improvement of the method of hydraulic profiling of the RBMK-1500 core at the Ignalina nuclear power plant is examined.\\u000a The hydraulic profiling method employs an approach where an adequate margin up to a crisis of heat transfer is provided in\\u000a the channels of the reactor, the mass steam content at all channel exits is kept uniform, the number of

E. Ushpuras; V. Matuzas; V. Kopustinskas; Yu. Augutis; G. Krivoshein; N. Lebedevichus

2006-01-01

65

Modeling the performance of the piston ring-pack with consideration of non-axisymmetric characteristics of the power cylinder system in internal combustion engines  

E-print Network

The performance of the piston ring-pack is directly associated with the friction, oil consumption, wear, and blow-by in internal combustion engines. Because of non-axisymmetric characteristics of the power cylinder system, ...

Liu, Liang, 1971-

2005-01-01

66

A reconfigurable battery pack for improving power conversion efficiency in portable devices  

Microsoft Academic Search

Extending battery life for portable computing systems not only requires new power management techniques and high efficiency power delivery systems but also must address low power consumption modes. Mobile systems spend most of their operating time in very low power modes, in which the voltage regulators (VRs) that feed the different components typically exhibit low efficiencies. Variable frequency control is

H. Visairo; P. Kumar

2008-01-01

67

Simultaneous transient operation of a high head hydro power plant and a storage pumping station in the same hydraulic scheme  

NASA Astrophysics Data System (ADS)

This paper presents an on-site experimental analysis of a high head hydro power plant and a storage pumping station, in an interconnected complex hydraulic scheme during simultaneous transient operation. The investigated hydropower site has a unique structure as the pumping station discharges the water into the hydropower plant penstock. The operation regimes were chosen for critical scenarios such as sudden load rejections of the turbines as well as start-ups and stops with different combinations of the hydraulic turbines and pumps operation. Several parameters were simultaneously measured such as the pumped water discharge, the pressure at the inlet pump section, at the outlet of the pumps and at the vane house of the hydraulic power plant surge tank. The results showed the dependence of the turbines and the pumps operation. Simultaneous operation of the turbines and the pumps is possible in safe conditions, without endangering the machines or the structures. Furthermore, simultaneous operation of the pumping station together with the hydropower plant increases the overall hydraulic efficiency of the site since shortening the discharge circuit of the pumps.

Bucur, D. M.; Dunca, G.; Cervantes, M. J.; C?linoiu, C.; Isb??oiu, E. C.

2014-12-01

68

Quasi-open loop hydraulic ram incremental actuator with power conserving properties  

Microsoft Academic Search

An electric stepping motor, operated by command signals from a computer or a microprocessor, rotates a rotary control member of a distributor valve, for sequencing hydraulic pressure and hence flow to the cylinders of an axial piston hydraulic machine. A group of the cylinders are subjected to pressure and flow and the remaining cylinders are vented to a return line.

E. T. Raymond; C. W. Robinson

1982-01-01

69

Evaluation of Army engine oils in hydraulic/power-transmission-system components. Final report, August 1984-November 1985  

SciTech Connect

The objective of the MACI Hydraulic System and Components Program is to perform technical evaluation and assessment of commerically available qualified and fielded Army engine oils and to determine if such oils can be used as hydraulic fluids in Army commercial construction equipment and material-handling equipment. Five Army specification engine lubricants--four MIL-L-2104D (one grade 10W, one grade 30, two grade 15W-40) and one MIL-L-46167, grade 0W-20--were evaluated using four critical component performance tests used by manufacturers. Data compiled from this and previous work have shown that the limiting factors of the Army engine oils used as hydraulic and multipurpose power transmission fluids appear to be (1) wet-brake chatter noise, (2) hydraulic-pump wear problems with some piston pumps using MIL-L-46167 Arctic engine oils at temperatures hotter-than-expected Arctic conditions, and possibly (3) copper corrosion. The prime area of concern is the wet-brake chatter noise.

Marbach, H.W.; Lestz, S.J.

1985-11-01

70

Thermal-hydraulic analysis of cross-shaped spiral fuel in high power density BWRs  

E-print Network

Preliminary analysis of the cross-shaped spiral (CSS) fuel assembly suggests great thermal-hydraulic upside. According to computational models, the increase in rod surface area, combined with an increase in coolant turbulence ...

Conboy, Thomas M

2007-01-01

71

American Recovery & Reinvestment Act: Fuel Cell Hybrid Power Packs and Hydrogen Refueling for Lift Trucks  

SciTech Connect

HEB Grocery Company, Inc. (H-E-B) is a privately-held supermarket chain with 310 stores throughout Texas and northern Mexico. H-E-B converted 14 of its lift reach trucks to fuel cell power using Nuvera Fuel Cells’ PowerEdge™ units to verify the value proposition and environmental benefits associated with the technology. Issues associated with the increasing power requirements of the distribution center operation, along with high ambient temperature in the summer and other operating conditions (such as air quality and floor surface condition), surfaced opportunities for improving Nuvera’s PowerEdge fuel cell system design in high-throughput forklift environments. The project included on-site generation of hydrogen from a steam methane reformer, called PowerTap™ manufactured by Nuvera. The hydrogen was generated, compressed and stored in equipment located outside H-E-B’s facility, and provided to the forklifts by hydrogen dispensers located in high forklift traffic areas. The PowerEdge fuel cell units logged over 25,300 operating hours over the course of the two-year project period. The PowerTap hydrogen generator produced more than 11,100 kg of hydrogen over the same period. Hydrogen availability at the pump was 99.9%. H-E-B management has determined that fuel cell forklifts help alleviate several issues in its distribution centers, including truck operator downtime associated with battery changing, truck and battery maintenance costs, and reduction of grid electricity usage. Data collected from this initial installation demonstrated a 10% productivity improvement, which enabled H-E-B to make economic decisions on expanding the fleet of PowerEdge and PowerTap units in the fleet, which it plans to undertake upon successful demonstration of the new PowerEdge reach truck product. H-E-B has also expressed interst in other uses of hydrogen produced on site in the future, such as for APUs used in tractor trailers and refrigerated transport trucks in its fleet.

Block, Gus

2011-07-31

72

Hydraulics calculations for hydraulic Stirling engines  

SciTech Connect

The role of hydraulic devices and processes in Stirling engine design is discussed. Simple and conveniently organized algorithms are presented for the calculation of hydraulic system losses and for optimization of clearance seals. Fluid makeup system losses are discussed. The fluid inertia tube is compared with the free hydraulic piston. Scaling of power piston flow loss with engine design power level is such that flow loss inefficiencies tend to be large for engine power levels above a few hundred watts unless specific measures are taken to minimize the piston flow loss. A method for eliminating the power piston flow loss in large engines is discussed.

Riggle, P.; Emigh, S.G.; Lo, N.S.C.; Noble, J.E.; Olan, R.W.; White, M.A.

1984-08-01

73

*sja@iet.aau.dkwww.iet.aau.dk Development of a 400 W High Temperature PEM Fuel Cell Power Pack : Fuel Cell Stack Test  

E-print Network

temperature PEM fuel cells (LTPEM). When using HTPEM fuel cells, no membrane hydration problems occur*sja@iet.aau.dkwww.iet.aau.dk Development of a 400 W High Temperature PEM Fuel Cell Power Pack for fuel cells can redu- ce fuel storage volume considerably. The PBI membrane technology used in high

Berning, Torsten

74

PowerPack: Energy Profiling and Analysis of High-Performance Systems and Applications  

E-print Network

and energy are primary concerns in modern high- performance computing system design. Operational costs. The need for high-performance comput- ing power efficiency is further amplified when considered]. To improve the energy efficiency of high-performance computing systems and applications, it is critical

75

Hydraulic design of a re-circulating water cooling system of a combined cycle power plant in Thailand  

SciTech Connect

The paper describes the hydraulic design and hydraulic transient analysis of the re-circulating water cooling system of the combined cyclo Sipco power cogeneration plant in Thailand. The power plant of 450 MW total capacity is proposed to be built in two stages. Stage one will produce 300 MW of power and will consist of two gas turbine generators (GTG) and one steam turbine generator (STG). Stage two will produce 150 MW of power and will consist of one GTG and one STG. The cooling system will consist of one GTG and one STG. The cooling system will consist of cooling towers, a combined collecting basin and pump intake sump, pumps and motors, and separate conveyance systems and condensers for the generator units in the two stages. In a re-circulating water cooling system, cold water is pumped from the pump intake sump to the condensers through the conveyance system and hot water from the condensers is carried through the returning pipeline system to the cooling towers, whence the water after cooling is drained into the sump at the base of the towers. Total cooling water requirement for the system in stage one is estimated to be 112,000 gallons per minute (GPM), and that in stage two, 56,000 GPM. The sump is designed using the computer program HEC-2, developed by the US Army Corps of Engineers (COE) and the pump intake basin, following the recommendations of the Hydraulic Institute. The pumps were sized by computing the head loss in the system, and, the steady state and transient performances (during pump start-up and shut-down procedures and due to possible power or mechanical failure of one or all pumps) of the system were analyzed by mathematically modeling the system using the computer program WHAMO (Water Hammer nd Mass Oscillations), also developed by the COE.

Sarkar, C.K.; Pandit, D.R. [Parsons Infrastructure and Technology Group, Boston, MA (United States); Kwon, S.G. [Kolon Engineering and Construction Co., Ltd., Seoul (Korea, Republic of)

1998-12-31

76

Thermal-hydraulics Analysis of a Radioisotope-powered Mars Hopper Propulsion System  

SciTech Connect

Thermal-hydraulics analyses results produced using a combined suite of computational design and analysis codes are presented for the preliminary design of a concept Radioisotope Thermal Rocket (RTR) propulsion system. Modeling of the transient heating and steady state temperatures of the system is presented. Simulation results for propellant blow down during impulsive operation are also presented. The results from this study validate the feasibility of a practical thermally capacitive RTR propulsion system.

Robert C. O'Brien; Andrew C. Klein; William T. Taitano; Justice Gibson; Brian Myers; Steven D. Howe

2011-02-01

77

Reactor thermal-hydraulic FY 1986 status report for the multimegawatt Space Nuclear Power Program  

SciTech Connect

PNL's 1986 activities can be divided into three basic areas: code assessment, correlation assessment and experimental activities. The ultimate goal of all these activities is developing computer codes and verifying their use to perform the thermal-hydraulic analysis and design of the reactor core and plenum of the various proposed concepts. To perform this task as assessment is made of existing computer codes, models, correlations, and microgravity experimental data.

Krotiuk, W.J.; Antoniak, Z.I.

1986-10-01

78

Degradation of Phosphate Ester Hydraulic Fluid in Power Station Turbines Investigated by a Three-Magnet Unilateral Magnet Array  

PubMed Central

A three-magnet array unilateral NMR sensor with a homogeneous sensitive spot was employed for assessing aging of the turbine oils used in two different power stations. The Carr-Purcell-Meiboom-Gill (CPMG) sequence and Inversion Recovery-prepared CPMG were employed for measuring the 1H-NMR transverse and longitudinal relaxation times of turbine oils with different service status. Two signal components with different lifetimes were obtained by processing the transverse relaxation curves with a numeric program based on the Inverse Laplace Transformation. The long lifetime components of the transverse relaxation time T2eff and longitudinal relaxation time T1 were chosen to monitor the hydraulic fluid aging. The results demonstrate that an increase of the service time of the turbine oils clearly results in a decrease of T2eff,long and T1,long. This indicates that the T2eff,long and T1,long relaxation times, obtained from the unilateral magnetic resonance measurements, can be applied as indices for degradation of the hydraulic fluid in power station turbines. PMID:24736132

Guo, Pan; He, Wei; García-Naranjo, Juan C.

2014-01-01

79

Dual reservoir tank for propellant hydraulic fluid for internal combustion engine hydraulically driven cooling fan and for power steering actuating fluid  

SciTech Connect

This patent describes an internal combustion engine reservoir tank comprising a dividing wall between: (a) a first reservoir tank portion for storing a reserve of the first propellant hydraulic fluid, the first flow being taken from the first reservoir tank portion and being returned to the first reservoir tank portion; and (b) a second reservoir tank portion directly adjacent the first reservoir tank portion for storing a reserve of the second propellant hydraulic fluid, the second flow being taken from the second reservoir tank portion and being returned to the second reservoir tank portion.

Fukami, K.; Inagaki, M.; Oomura, S.; Hamamoto, T.

1989-01-03

80

Dual reservoir tank for propellant hydraulic fluid for internal combustion engine hydraulically driven cooling fan and for power steering actuating fluid  

Microsoft Academic Search

This patent describes an internal combustion engine reservoir tank comprising a dividing wall between: (a) a first reservoir tank portion for storing a reserve of the first propellant hydraulic fluid, the first flow being taken from the first reservoir tank portion and being returned to the first reservoir tank portion; and (b) a second reservoir tank portion directly adjacent the

K. Fukami; M. Inagaki; S. Oomura; T. Hamamoto

1989-01-01

81

APPLICATION OF MIKE PACKAGE TO ASSESS HYDRAULIC REGIMES AND FLOOD MAPPING WHEN CONSTRUCTION OF THERMAL POWER AT THE MONG DUONG ESTUARY (QUANG NINH)  

Microsoft Academic Search

The article presents the results formulated the effect to hydraulic regimes and inundated areas when construction of thermal power factory at the estuary of Mong Duong river by using the package of MIKE including Mike NAM, Mike11-HD and Mike-GIS with 2 options of canal width as well its location. The simulated results show that Mike package seems feasibly to formulate

VU MINH CAT; BUI DU DUONG

2007-01-01

82

46 CFR 111.97-5 - Electric and hydraulic power supply.  

Code of Federal Regulations, 2014 CFR

...111.97-5 Section 111.97-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Electric Power-Operated Watertight Door Systems §...

2014-10-01

83

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...

84

Hydraulics Lectures  

NSDL National Science Digital Library

This page from the WindTech TV project provides a link to lectures created by Jim Pytel for his hydraulics course at Columbia Gorge Community College. The lectures consist of live videos and screen capture style presentations and may be viewed free of charge. Clicking on the video link in the center of the page will lead users to a YouTube page with 31 lectures. Topics include hydraulics math, hydraulic safety, basic hydraulic schematics, viscosity, piston pumps, actuators, troubleshooting and more. These lectures would be extremely useful for technical and community college students taking a fundamental hydraulics course. Flash is required to view the videos.

Pytel, Jim

85

Basic Modeling and Simulation Tool for Analysis of Hydraulic Transients in Hydroelectric Power Plants  

Microsoft Academic Search

In this paper, the simulation system of a typical hydroelectric power plant was developed in a MATLAB\\/Simulink-based software environment, which has a high water head and a long penstock with upstream and downstream surge tanks and is equipped with a Francis turbine. With MATLAB\\/Simulink, the models of the proposed simulation system are all modularized and visualized, and can be reused

Hongqing Fang; Long Chen; Nkosinathi Dlakavu; Zuyi Shen

2008-01-01

86

Investigation of alternate power source for Space Shuttle Orbiter hydraulic system  

NASA Astrophysics Data System (ADS)

This investigation consists of a short-term feasibility study to determine whether or not an alternate electrical power source would trade favorably from a performance, reliability, safety, operation, and weight standpoint in replacing the current auxiliary power unit subsystems with its attendant components (water spray boiler, hydrazine fuel and tanks, feed and vent lines, controls, etc.), operating under current flight rules. Results of this feasibility study are used to develop recommendations for the next step (e.g., to determine if such an alternate electrical power source would show an advantage given that the current operational flight mode of the system could be modified in such a way as not to constrain the operational capability and safety of the vehicle). However, this next step is not within the scope of this investigation. This study does not include a cost analysis, nor does it include investigation of the integration aspects involved in such a trade, except in a qualitative sense for the determination of concept feasibility.

Simon, William E.; Young, Fred M.

1993-05-01

87

Investigation of alternate power source for Space Shuttle Orbiter hydraulic system  

NASA Technical Reports Server (NTRS)

This investigation consists of a short-term feasibility study to determine whether or not an alternate electrical power source would trade favorably from a performance, reliability, safety, operation, and weight standpoint in replacing the current auxiliary power unit subsystems with its attendant components (water spray boiler, hydrazine fuel and tanks, feed and vent lines, controls, etc.), operating under current flight rules. Results of this feasibility study are used to develop recommendations for the next step (e.g., to determine if such an alternate electrical power source would show an advantage given that the current operational flight mode of the system could be modified in such a way as not to constrain the operational capability and safety of the vehicle). However, this next step is not within the scope of this investigation. This study does not include a cost analysis, nor does it include investigation of the integration aspects involved in such a trade, except in a qualitative sense for the determination of concept feasibility.

Simon, William E.; Young, Fred M.

1993-01-01

88

International Journal of Fluid Power Vol. 5(2). pp. 43-56, 2004. PASSIVE BILATERAL TELEOPERATION OF A HYDRAULIC  

E-print Network

and the hydraulic actuator converges to zero for sufficiently low manipulation bandwidth. Experimental results OF A HYDRAULIC ACTUATOR USING AN ELECTROHYDRAULIC PASSIVE VALVE Perry Y. Li and Kailash Krishnaswamy Department a motorized joystick to feel as if he is manipulating a rigid mechanical tool with which the work environment

Li, Perry Y.

89

Portable Hydraulic Powerpack  

NASA Technical Reports Server (NTRS)

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.

Anderson, L. A.; Henry, R. L.; Fedor, O. H.; Owens, L. J.

1986-01-01

90

Variable-Displacement Hydraulic Drive Unit  

NASA Technical Reports Server (NTRS)

Hydraulic power controlled through multiple feedback loops. In hydraulic drive unit, power closely matched to demand, thereby saving energy. Hydraulic flow to and from motor adjusted by motor-control valve connected to wobbler. Wobbler angle determines motor-control-valve position, which in turn determines motor displacement. Concept applicable to machine tools, aircraft controls, and marine controls.

Lang, D. J.; Linton, D. J.; Markunas, A.

1986-01-01

91

Hydraulics. FOS: Fundamentals of Service.  

ERIC Educational Resources Information Center

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…

John Deere Co., Moline, IL.

92

Carbonization and activation of inexpensive semicoke-packed electrodes to enhance power generation of microbial fuel cells.  

PubMed

A simple and low-cost modification method was developed to improve the power generation performance of inexpensive semicoke electrode in microbial fuel cells (MFCs). After carbonization and activation with water vapor at 800-850?°C, the MFC with the activated coke (modified semicoke) anode produced a maximum power density of 74 Wm(-3) , 17 Wm(-3) , and 681 mWm(-2) (normalized to anodic liquid volume, total reactor volume, and projected membrane surface area, respectively), which was 124 % higher than MFCs using a semicoke anode (33 Wm(-3) , 8 Wm(-3) , and 304 mWm(-2) ). When they were used as biocathode materials, activated coke produced a maximum power density of 177 Wm(-3) , 41 Wm(-3) , and 1628 mWm(-2) (normalized to cathodic liquid volume, total reactor volume, and projected membrane surface area, respectively), which was 211 % higher than that achieved by MFCs using a semicoke cathode (57 Wm(-3) , 13 Wm(-3) , and 524 mWm(-2) ). A substantial increase was also noted in the conductivity, C/O mass ratio, and specific area for activated coke, which reduced the ohmic resistance, increased biomass density, and promoted electron transfer between bacteria and electrode surface. The activated coke anode also produced a higher Coulombic efficiency and chemical oxygen demand removal rate than the semicoke anode. PMID:22639403

Wei, Jincheng; Liang, Peng; Zuo, Kuichang; Cao, Xiaoxin; Huang, Xia

2012-06-01

93

Missile Roll Control We wish to design a feedback controller for a missile, using hydraulic-powered ailerons, that will  

E-print Network

Missile Roll Control We wish to design a feedback controller for a missile, using hydraulic( ) ( )t( )t Q/ ( )t 1 1 s s + 1/ s Design a feedback controller that will move the roll attitude. Discuss your design steps and the reasons for your final design. Your design process should involve

Hagan, Martin

94

PERFORMANCE OF AN AERIAL VARIABLE-RATE APPLICATION SYSTEM WITH A HYDRAULICALLY POWERED CHEMICAL PUMP AND SPRAY VALVE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The performance was evaluated for a variable-rate system that consisted of a SATLOC M3 with AirTrac software with WAAS corrected DGPS (5 Hz position update) and an AutoCal II automatic flow controller. This system was installed on an Air Tractor 402B equipped with an auxiliary hydraulic package tha...

95

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

ERIC Educational Resources Information Center

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…

Human Engineering Inst., Cleveland, OH.

96

On Discrete Hyperbox Packing  

E-print Network

Bin packing is a very important and popular research area in the computer science field. Past work showed many good and real-world packing algorithms. How- ever, due to the complexity of the problem in multiple-dimensional bin packing, also called...

Li, Xiafeng

2010-01-14

97

Differential Geometry: Circle Packings  

E-print Network

Differential Geometry: Circle Packings [CirclePack, Ken Stephenson] [A Circle Packing Algorithm if it preserves oriented angles. That is, the map sends "tiny" circles to circles. Re Re Re ImImIm f(z)=z2.2 f the curve to the unit disk. #12;Conformal Maps Intuition: Since conformal maps send "tiny" circles

Kazhdan, Michael

98

Extended Kalman filtering for battery management systems of LiPB-based HEV battery packs  

Microsoft Academic Search

Battery management systems in hybrid electric vehicle battery packs must estimate values descriptive of the pack’s present operating condition. These include: battery state of charge, power fade, capacity fade, and instantaneous available power. The estimation mechanism must adapt to changing cell characteristics as cells age and therefore provide accurate estimates over the lifetime of the pack.In a series of three

Gregory L. Plett

2004-01-01

99

Electrically recharged battery employing a packed/spouted bed metal particle electrode  

DOEpatents

A secondary metal air cell, employing a spouted/packed metal particle bed and an air electrode. More specifically a zinc air cell well suited for use in electric vehicles which is capable of being either electrically or hydraulically recharged.

Siu, Stanley C. (Alameda, CA); Evans, James W. (Piedmont, CA); Salas-Morales, Juan (Berkeley, CA)

1995-01-01

100

Thermal hydraulic calculations to support increase in operating power in McClellen Nuclear Radiation Center(MNRC) TRIGA reactor.  

SciTech Connect

The RELAP5/Mod3.1 computer program has been used to successfully perform thermal-hydraulic analyses to support the Safety Analysis for increasing the MNRC reactor from 1.0 MW to 2.0 MW. The calculation results show the reactor to have operating margin for both the fuel temperature and critical heat flux limits. The calculated maximum fuel temperature of 705 C is well below the 750 C operating limit. The critical heat flux ratio was calculated to be 2.51.

Jensen, R. T.

1998-05-05

101

Orderly Packed Anodes for High-Power Lithium-Ion Batteries with Super-Long Cycle Life: Rational Design of MnCO3 /Large-Area Graphene Composites.  

PubMed

MnCO3 particles uniformly distributed on large-area graphene form 2D composites whose large-area character enables them to self-assemble face-to-face into orderly packed electrodes. Such regular structures form continuous and efficient transport networks, leading to outstanding lithium storage with high capacity, ultralong cycle life, and excellent rate capability - all characteristics that are required for high-power lithium-ion batteries. PMID:25523603

Zhong, Yiren; Yang, Mei; Zhou, Xianlong; Luo, Yuting; Wei, Jinping; Zhou, Zhen

2015-02-01

102

THERMAL HYDRAULICS KEYWORDS: thermal hydraulics,  

E-print Network

-fluid modeling of nuclear reactor systems. Thermal-hydraulic analysis codes such as RELAP5-3D ~Ref. 1! and FLICA regions of the system. In fact, the CFD code FLUENT has previously been coupled to RELAP5-3D ~Refs. 3

Smith, Barton L.

103

Hydraulic Arm Challenge  

NSDL National Science Digital Library

Students design and build a mechanical arm that lifts and moves an empty 12-ounce soda can using hydraulics for power. Small design teams (1-2 students each) design and build a single axis for use in the completed mechanical arm. One team designs and builds the grasping hand, another team the lifting arm, and a third team the rotation base. The three groups must work to communicate effectively through written and verbal communication and sketches.

Center for Engineering Educational Outreach,

104

Leaf Pack Network  

NSDL National Science Digital Library

The Leaf Pack Network (LPN) is a network of teachers and students investigating their local stream ecosystems by participating in the leaf pack experiment, which involves creating an artificial leaf pack (dry leaves in a mesh bag), immersing it in a stream for 3-4 weeks, and examining it for signs of aquatic insects as indicators of stream health. Participating classrooms share their data through the internet. This activity highlights the connection between streamside forests and the ecology of rivers and streams.

105

Physico-chemical characterization of mortars as a tool in studying specific hydraulic components: application to the study of ancient Naxos aqueduct  

NASA Astrophysics Data System (ADS)

Mortars and plasters from the ancient aqueduct on the island of Naxos, Greece, were studied with regard to mineralogical and chemical composition, grain size distribution, raw materials and hydraulic properties, in order to assess their characteristics and design compatible repair mortars. The authentic materials contained lime, crushed-brick, siliceous and calcitic aggregates, in different proportions according to mortar type. Crushed-bricks fired at low temperatures and lightweight volcanic aggregates contained amorphous phases, which upon reaction with lime yielded hydraulic components capable of protecting the construction from the continuous presence of water. Hydraulic calcium silicate/aluminate hydrates, the proportions and the perfect packing of the raw materials, along with the diligent application justify the longevity and durability of the studied samples. The hydraulic properties of samples were pointed out through (a) the well-established CO2/H2O ratio derived from the thermogravimetric analysis and (b) by introducing two powerful indices issued from the chemical analysis, namely CaOhydr and soluble SiO2 hydr. These indices improved the clustering of hydraulic mortars and provided better correlation between mortars, plasters and their binders. By comparing grain size distribution and hydraulicity indices it was possible to distinguish among the construction phases. Based on this study, repair mortars were formulated by hydraulic lime, siliceous sand, calcareous and crushed-brick aggregates, with the optimal water content, ensuring optimum workability and compatible appearance with the authentic ones.

Maravelaki-Kalaitzaki, P.; Galanos, A.; Doganis, I.; Kallithrakas-Kontos, N.

2011-07-01

106

Modeling, Simulation, and Control of a Hydraulic Stewart Platform  

E-print Network

-controls along six degrees of freedom. The hydraulic actuation system includes a hydraulic power supply unit Power Supply Chair Base Electrical Box Hand Controls Distribution System Figure 1: Diagram of the motion. Although hydraulic Stewart platforms have been used for years in aircraft simulators,and some are now

Salcudean, Tim

107

The hydraulic conductivity of chopped sorghum forage  

E-print Network

, Darcy's law is (Schwab, et al. , 1966) 0 = KA L '(Eq. I ) H where Q &s the flow rate (cm&/sec) through the medium. K is the hydraulic conductivity (cm/sec) of the porous medium. A is the cross sectional area (cm2) of the packed bed and is measured... in the plane perpendicular to the direction of flow. H/L is the potential gradient (cm/cm), or head loss per unit length, Rearranging this equation gives an expression for the hydraulic conductivity, K, in terms of the other parameters: Q L A H (Eq. 2...

Custer, Micheal Hugh

2012-06-07

108

Hydraulic fracturing-1  

SciTech Connect

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.

Not Available

1990-01-01

109

Kinetic ceramics piezoelectric hydraulic pumps  

NASA Astrophysics Data System (ADS)

This paper discusses the development and testing of two Piezoelectrically driven Hydraulic Pumps (PHP2 & PHP3) utilizing low cost discrete multilayer piezoelectric actuators and low cost structural components. New valve technologies were developed utilizing reed and MEMS valves. Structural optimization was performed to decrease weight and volume. The PHP3 design extracts power from a PZT material with high efficiency despite impedance mismatch between the piezoelectric actuator and fluid by utilizing a hydraulic pendulum energy recovery technique. Hydraulic power of 168 watts can be developed with a pump mass of under 1lb. Flow rate of 2300 cc/min free flow has been demonstrated as well as output pressure greater than 200 bar in the stalled condition. The result of the effort is practical solid state conversion of electrical energy into a useable hydraulic source for actuation systems without having normal rotational wear components. The PHP2 pump was used to power the hydraulic primary flight controls in a RPV technology demonstrator flight tested in November 2006.

O'Neill, Conal; Burchfield, John

2007-04-01

110

Development, setup and testing of a dynamic hydraulic fracture conductivity apparatus  

E-print Network

One of the most critical parameters in the success of a hydraulic fracturing treatment is to have sufficiently high fracture conductivity. Unbroken polymers can cause permeability impairment in the proppant pack and/or in the matrix along...

Pongthunya, Potcharaporn

2009-06-02

111

Foam gravel packing  

SciTech Connect

Foam gravel packing experiments run in a fullscale model wellbore demonstrated that foam is a viable alternative to conventional carrier fluids such as water and viscous polymer solutions in select instances. Because of its special characteristics, foam may have advantages over these fluids in completions where low pressure or sensitive formations are encountered. Results from experiments were used to design and implement gravel pack completions in nine shallow, low pressure wells in California. Other wells in the area had a history of lost circulation and washouts during drilling and completion operations using conventional fluids. The foam gravel packs suffered no loss of circulation during placement and proved to be less costly than the conventional slurry packs used in the past.

Elson, T.D.; Anderson, G.W.

1983-03-01

112

Packing Peanut Properties  

NSDL National Science Digital Library

Students work with various types of packing peanuts to investigate states of matter and chemical and physical changes. One of the activities involves making slime. The activities can easily be modified for students with learning disabilities.

Hall, Dori; Hall, Sue

2002-02-02

113

Nasal packing and stenting  

PubMed Central

Nasal packs are indispensable in ENT practice. This study reviews current indications, effectiveness and risks of nasal packs and stents. In endoscopic surgery, nasal packs should always have smooth surfaces to minimize mucosal damage, improve wound healing and increase patient comfort. Functional endoscopic endonasal sinus surgery allows the use of modern nasal packs, since pressure is no longer required. So called hemostatic/resorbable materials are a first step in this direction. However, they may lead to adhesions and foreign body reactions in mucosal membranes. Simple occlusion is an effective method for creating a moist milieu for improved wound healing and avoiding dryness. Stenting of the frontal sinus is recommended if surgery fails to produce a wide, physiologically shaped drainage path that is sufficiently covered by intact tissue. PMID:22073095

Weber, Rainer K.

2011-01-01

114

Micromachined hydraulic astable multivibrator  

Microsoft Academic Search

1 Abstract The paper presents a hydraulic astable multivibrator system. The system consists of hydraulic resistors, hydraulic capacitors and hydraulic pressure controlled valves. The system is designed, realised and tested. The measured system behaviour agrees well with the model simulations. The free running frequency of the multivibrator is 0.18 Hz and the output pressure swing is 90% of the supply

T. S. J. Lammerink; N. R. Tas; J. W. Berenschot; M. C. Elwenspoek; J. H. J. Fluitman

1995-01-01

115

Densest binary sphere packings  

NASA Astrophysics Data System (ADS)

The densest binary sphere packings in the ?-x plane of small to large sphere radius ratio ? and small sphere relative concentration x have historically been very difficult to determine. Previous research had led to the prediction that these packings were composed of a few known “alloy” phases including, for example, the AlB2 (hexagonal ?), HgBr2, and AuTe2 structures, and to XYn structures composed of close-packed large spheres with small spheres (in a number ratio of n to 1) in the interstices, e.g., the NaCl packing for n=1. However, utilizing an implementation of the Torquato-Jiao sphere-packing algorithm [Torquato and Jiao, Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.82.061302 82, 061302 (2010)], we have discovered that many more structures appear in the densest packings. For example, while all previously known densest structures were composed of spheres in small to large number ratios of one to one, two to one, and very recently three to one, we have identified densest structures with number ratios of seven to three and five to two. In a recent work [Hopkins , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.107.125501 107, 125501 (2011)], we summarized these findings. In this work, we present the structures of the densest-known packings and provide details about their characteristics. Our findings demonstrate that a broad array of different densest mechanically stable structures consisting of only two types of components can form without any consideration of attractive or anisotropic interactions. In addition, the structures that we have identified may correspond to currently unidentified stable phases of certain binary atomic and molecular systems, particularly at high temperatures and pressures.

Hopkins, Adam B.; Stillinger, Frank H.; Torquato, Salvatore

2012-02-01

116

Promoting water hydraulics in Malaysia: A green educational approach  

NASA Astrophysics Data System (ADS)

In promoting water hydraulics in Malaysia, this paper presents research development of water hydraulics educational training system for secondary and tertiary levels in Malaysia. Water hydraulics trainer with robotic attachment has been studied in order to promote the usefulness of such educational tools in promoting sustainability and green technology in the country. The trainer is being developed in order to allow constructive curriculum development and continuous marketing research for the effectiveness and usefulness of using water in hydraulic power trainer. The research on water-based hydraulic trainer is now possible with the current development in water hydraulics technology.

Yusof, Ahmad Anas; Zaili, Zarin Syukri; Hassan, Siti Nor Habibah; Tuan, Tee Boon; Saadun, Mohd Noor Asril; Ibrahim, Mohd Qadafie

2014-10-01

117

Theory of random packings  

NASA Astrophysics Data System (ADS)

We review a recently proposed theory of random packings. We describe the volume fluctuations in jammed matter through a volume function, amenable to analytical and numerical calculations. We combine an extended statistical mechanics approach `a la Edwards' (where the role traditionally played by the energy and temperature in thermal systems is substituted by the volume and compactivity) with a constraint on mechanical stability imposed by the isostatic condition. We show how such approaches can bring results that can be compared to experiments and allow for an exploitation of the statistical mechanics framework. The key result is the use of a relation between the local Voronoi volume of the constituent grains and the number of neighbors in contact that permits a simple combination of the two approaches to develop a theory of random packings. We predict the density of random loose packing (RLP) and random close packing (RCP) in close agreement with experiments and develop a phase diagram of jammed matter that provides a unifying view of the disordered hard sphere packing problem and further shedding light on a diverse spectrum of data, including the RLP state. Theoretical results are well reproduced by numerical simulations that confirm the essential role played by friction in determining both the RLP and RCP limits. Finally we present an extended discussion on the existence of geometrical and mechanical coordination numbers and how to measure both quantities in experiments and computer simulations.

Song, Chaoming; Wang, Ping; Makse, Hernán A.

2010-05-01

118

46 CFR 58.30-10 - Hydraulic fluid.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Hydraulic fluid. 58.30-10 Section 58...and Control Systems § 58.30-10 Hydraulic fluid. (a) The requirements...inspection. (b) The fluid used in hydraulic power transmission systems shall...

2010-10-01

119

Extended Kalman filtering for battery management systems of LiPB-based HEV battery packs  

Microsoft Academic Search

Battery management systems in hybrid-electric-vehicle battery packs must estimate values descriptive of the pack’s present operating condition. These include: battery state-of-charge, power fade, capacity fade, and instantaneous available power. The estimation mechanism must adapt to changing cell characteristics as cells age and therefore provide accurate estimates over the lifetime of the pack.In a series of three papers, we propose methods,

Gregory L. Plett

2004-01-01

120

Extended Kalman filtering for battery management systems of LiPB-based HEV battery packs  

Microsoft Academic Search

Abstract Battery management,systems in hybrid-electric-vehicle battery packs must estimate values descriptive of the pack’s present operating condition. These include: battery state-of-charge, power fade, capacity fade, and instantaneous available power. The estimation mechanism must adapt to changing,cell characteristics as cells age and therefore provide accurate estimates over the lifetime of the pack. In a series of three papers, we propose methods,

Gregory L. Plett

121

Extended Kalman filtering for battery management systems of LiPB-based HEV battery packs  

Microsoft Academic Search

Battery management systems (BMS) in hybrid-electric-vehicle (HEV) battery packs must estimate values descriptive of the pack’s present operating condition. These include: battery state of charge, power fade, capacity fade, and instantaneous available power. The estimation mechanism must adapt to changing cell characteristics as cells age and therefore provide accurate estimates over the lifetime of the pack.In a series of three

Gregory L. Plett

2004-01-01

122

Downstream hydraulic geometry relations: 1. Theoretical development  

E-print Network

. The second hypothesis is a result of the principles of maximum entropy and minimum energy dissipation or its simplified minimum stream power. These two hypotheses lead to four families of downstream hydraulic geometry relations. The conditions under which...

Singh, Vijay P.; Yang, Chih Ted; Deng, Z. Q.

2003-12-04

123

Sensitivity study of the assembly averaged thermal-hydraulic models of the MEKIN computer code in power transients / by Thomas Rodack [and] Lothar Wolf  

E-print Network

The thermal-hydraulic (T-H) models and solution schemes employed by the MEKIN computer code have been examined. The effects of T-H input parameters on- predicted fuel temperatures and coolant densities were determined in ...

Rodack, Thomas

1977-01-01

124

Nutrition Action Pack.  

ERIC Educational Resources Information Center

One of five McDonald's Action Packs, these instructional materials integrate elementary school-level nutrition education into other disciplines--biology, sociology, physiology, mathematics, and art. Contents include four units consisting of twelve activities. Unit 1, Why You Need Food, is a self-examination of what is needed for growth, health,…

Sockut, Joanne; Stumpe, Stephanie

125

Find Your Pack  

NSDL National Science Digital Library

This activity introduces learners to wolf behavior and communication. Learners explore how wolves communicate with each other by using their sense of smell to identify members of their "pack." Activity also includes suggestions for connecting this activity to a discussion of how habitat loss can affect wolf populations.

Eduweb

2012-01-01

126

Packing Them In.  

ERIC Educational Resources Information Center

This activity involves students investigating the mathematics of packaging and exploring various concepts in geometry, including area and the Pythagorean theorem. Mathematics comes out of the discussion of packaging cans into six-packs and focuses on the cost-effectiveness of the horizontal storage area used. Students learn how knowledge of…

Carter, Claudia

1997-01-01

127

DIY Fraction Pack.  

ERIC Educational Resources Information Center

Describes a very successful attempt to teach fractions to year 5 pupils based on pupils making their own fraction pack. Children decided for themselves how to make the fractional slices used in the activity using colored cardboard sheets and templates of a paper circle consisting of 24 equal slices. (Author/NB)

Graham, Alan; Graham, Louise

2003-01-01

128

Optimization of blended battery packs  

E-print Network

This thesis reviews the traditional battery pack design process for hybrid and electric vehicles, and presents a dynamic programming (DP) based algorithm that eases the process of cell selection and pack design, especially ...

Erb, Dylan C. (Dylan Charles)

2013-01-01

129

Computer simulations of particle packing  

Microsoft Academic Search

Computer code has been developed to rapidly simulate the random packing of disks and spheres in two and three dimensions. Any size distribution may be packed. The code simulates varying degrees of inter particle conditions ranging from sticky to free flowing. The code will also calculate the overall packing density, density distributions, and void size distributions (in two dimensions). An

J. Cesarano; M. J. McEuen; T. Swiler

1996-01-01

130

Piezoelectric hydraulic pump performance  

NASA Astrophysics Data System (ADS)

A piezohydraulic pump making use of the step and repeat capability of piezoelectric actuators has been developed for actuation of aircraft control surfaces. The piezohydraulic pump utilizes a piezoelectric stack actuator to drive a piston in a cylinder. The cylinder is fitted with two check valves. On the compression stroke, oil is forced out of the cylinder. On the intake stroke, oil is drawn into the cylinder. The oil is used to drive a linear actuator. The actuator was driven at 7cm/sec with a 271N (61lb) blocking force. To achieve this, the piezoelectric stack actuator was driven at 60Hz with a switching power supply. The system utilizes an accumulator to eliminate cavitation. This work discusses piezohydraulic pumping theory, pump design, and pump performance. Consideration of pump performance includes the effects of varying accumulator pressure, hydraulic oil viscosity, and load imposed on the linear actuator.

Mauck, Lisa D.; Oates, William S.; Lynch, Christopher S.

2001-06-01

131

Optimize bit hydraulics for minimum cost drilling  

SciTech Connect

In a previous paper, the authors derived a condition for optimum bit hydraulics considering increases in rate of penetration (ROP), fuel costs and pump maintenance costs with increased bit hydraulics. This paper is an extension of the previous work and demonstrates practical application of the new hydraulics optimization method. Previously unpublished full scale laboratory drilling data obtained by the authors and test results reported by other authors are presented to demonstrate the relationship of ROP to increased bit hydraulic horsepower. Effects of blanked nozzles and asymmetric nozzle configurations are also presented. Graphical relationships of fuel and pump maintenance cost increases, bit ROP increases and drilling cost variations with increasing standpipe pressure and bit hydraulic horsepower are presented. The optimum condition for bit hydraulics reveals that fuel costs to power mud pumps and pump maintenance costs should be a fixed percentage of total operating costs depending on bit ROP response to increased bit hydraulic horsepower. Recommendations for field application of the optimizing technique are presented.

Dolron, H.H.; Deane, J.D.

1983-02-01

132

[Electricity generation using the packing-type microbial fuel cells].  

PubMed

The packing-type microbial fuel cells (MFCs) were constructed using the granular graphite and the carbon felt as packing materials. The start-up time of the packing-type MFC was about 1 d, which was lower than that of the flat-type MFC. The maximal power density (Pm) of the MFC with carbon felt as packing material was 1502 mW/m2 (37.6 W/m3), which was higher than that with granular graphite as packing material. The carbon felt and carbon paper were sintered together to enhance the electric conductivity. Compared with the flat-type MFC, the area-specific resistance of the packing-type MFC decreased from 0.071 omega x m2 to 0.051 omega x m2, the maximal current density increased from 3000 mA to 8000 mA, the Pm increased from 1100 mW/m2 (27.5 W/m3) to 2426 mW/m2 (60.7 W/m3) and the potentials of anode decreased about 100 mV. The flow rate affected the power generation of the MFC. When the flow rate was lower than 1 mL/min, the Pm dropped with the flux decreasing. The packing-type MFC was operated for over 30 and the coulomb efficiency was about 10.6%. PMID:18613529

Liang, Peng; Fan, Ming-zhi; Cao, Xiao-xin; Huang, Xia; Huang, Zheng-hong; Wang, Cheng

2008-02-01

133

Electrically recharged battery employing a packed/spouted bed metal particle electrode  

DOEpatents

A secondary metal air cell, employing a spouted/packed metal particle bed and an air electrode, is described. More specifically a zinc air cell well suited for use in electric vehicles which is capable of being either electrically or hydraulically recharged. 5 figs.

Siu, S.C.; Evans, J.W.; Salas-Morales, J.

1995-08-15

134

Thermally Actuated Hydraulic Pumps  

NASA Technical Reports Server (NTRS)

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 vessels. Heretofore, electrically actuated hydraulic pumps have been used for this purpose. By eliminating the demand for electrical energy for pumping, the use of the thermally actuated hydraulic pumps could prolong the intervals between battery charges, thus making it possible to greatly increase the durations of undersea exploratory missions.

Jones, Jack; Ross, Ronald; Chao, Yi

2008-01-01

135

Packing-Limited Growth  

E-print Network

We consider growing spheres seeded by random injection in time and space. Growth stops when two spheres meet leading eventually to a jammed state. We study the statistics of growth limited by packing theoretically in d dimensions and via simulation in d=2, 3, and 4. We show how a broad class of such models exhibit distributions of sphere radii with a universal exponent. We construct a scaling theory that relates the fractal structure of these models to the decay of their pore space, a theory that we confirm via numerical simulations. The scaling theory also predicts an upper bound for the universal exponent and is in exact agreement with numerical results for d=4.

Peter Sheridan Dodds; Joshua S. Weitz

2002-03-12

136

Leaf Hydraulics Lawren Sack1  

E-print Network

Leaf Hydraulics Lawren Sack1 and N. Michele Holbrook2 1 Department of Botany, University of Hawai influence rates of transpiration and photosynthesis. Leaf hydraulic conductance (Kleaf) varies more than 65. #12;Contents INTRODUCTION. . . . . . . . . . . . . . . . . 362 LEAF HYDRAULIC CONDUCTANCE

Sack, Lawren

137

Suspensions in hydraulic fracturing  

Microsoft Academic Search

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

Shah

1996-01-01

138

Packing Products: Polystyrene vs. Cornstarch  

ERIC Educational Resources Information Center

Packing materials such as polystyrene take thousands of years to decompose, whereas packing peanuts made from cornstarch, which some companies are now using, can serve the same purpose, but dissolve in water. The author illustrates this point to her class one rainy day using the sculptures students made from polystyrene and with the cornstarch…

Starr, Suzanne

2009-01-01

139

The proof of the packing  

E-print Network

The proof of the packing Kepler's Conjecture: How Some of the Greatest Minds in History Helped astronomer Johannes Kepler stated that no packing could be denser than that of the face-centred cubic (f space. It took mathematicians some 400 years to prove him right. Kepler's Conjecture gives

Sloane, Neil J. A.

140

Downhole hydraulic seismic generator  

DOEpatents

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.

Gregory, Danny L. (Corrales, NM); Hardee, Harry C. (Albuquerque, NM); Smallwood, David O. (Albuquerque, NM)

1992-01-01

141

PureForce TM Hydraulic Filters Designed to Meet or Exceed Today's Equipment Requirements for High Performance  

Microsoft Academic Search

expense and help insure trouble-free system operation is through proper filtration. The hydraulic filter, which was once nonexistent in hydraulic systems, has now become a critical component. In fact, few other areas of filtration have changed as rapidly as hydraulics. The reason for such rapid change is that hydraulic systems are replacing other types of power transmissions. To improve safety

Pacific Rim; Ireland Baldwin

2009-01-01

142

7 CFR 51.1270 - Packing.  

Code of Federal Regulations, 2010 CFR

...FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing. (a) Each package shall be packed so that the pears in the shown...

2010-01-01

143

7 CFR 51.1270 - Packing.  

Code of Federal Regulations, 2011 CFR

...FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing. (a) Each package shall be packed so that the pears in the shown...

2011-01-01

144

PARTICLE PACKING PROBLEMS IN LOW SPACE DIMENSIONS  

E-print Network

vectors). · Periodic packing Packing obtained by placing a fixed arrangement of n ( 1) convex particles dependent. · Terms "random" and "close packed" are at odds with one another. · There has never been

Torquato, Salvatore

145

Nasal septal packing: which one?  

PubMed

The aim of this study was to investigate the effects of four different types of nasal packs on pain, nasal fullness and postoperative bleeding following septoplasty. Prospective randomised double blind study was conducted. The study group included 119 patients who underwent endonasal septoplasty under general anaesthesia. Four types of nasal packing materials were utilized: (1) Merocel standard 8-cm nasal dressing without airway, (2) Doyle Combo splint (DCS), (3) Merocel in a glove finger and (4) Vaseline gauze. All packs were removed at the 48th hour (±3 h) after the surgery. Three different variables were investigated following the surgical procedure: (1) pain, (2) nasal fullness and (3) bleeding after removal of the nasal packing material. DCS produced the greatest pain at the first and sixth postoperative hours. At the first postoperative day, the greatest pain score was reported for Merocel in the glove finger and the least for Merocel. The pain scores during the removal of the nasal packings were highest for Merocel and lowest for Merocel in the glove finger. DCS had the lowest nasal fullness score. Bleeding ratio was highest for Merocel, followed by Vaseline gauze, DCS and Merocel in the glove finger. Many different commercially available packing materials are presently used, each with inherent advantages and disadvantages. We evaluated the pain, nasal fullness and bleeding potential of four nasal packing materials and determined that Merocel had the highest pain potential during removal and the highest rate of bleeding following removal. PMID:22160143

Ac?o?lu, Engin; Edizer, Deniz Tuna; Yi?it, Özgür; Onur, F?rat; Alkan, Zeynep

2012-07-01

146

Valve stem and packing assembly  

DOEpatents

A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents over tightening of the retaining nut and the resulting excessive friction between stem and stem packing. 2 figures.

Wordin, J.J.

1991-09-03

147

Valve stem and packing assembly  

DOEpatents

A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents overtightening of the retaining nut and the resulting excessive friction between stem and stem packing.

Wordin, John J. (Bingham County, ID)

1991-01-01

148

Dense periodic packings of tori.  

PubMed

Dense packings of nonoverlapping bodies in three-dimensional Euclidean space R(3) are useful models of the structure of a variety of many-particle systems that arise in the physical and biological sciences. Here we investigate the packing behavior of congruent ring tori in R(3), which are multiply connected nonconvex bodies of genus 1, as well as horn and spindle tori. Specifically, we analytically construct a family of dense periodic packings of unlinked tori guided by the organizing principles originally devised for simply connected solid bodies [Torquato and Jiao, Phys. Rev. E 86, 011102 (2012)]. We find that the horn tori as well as certain spindle and ring tori can achieve a packing density not only higher than that of spheres (i.e., ?/sqrt[18] = 0.7404...) but also higher than the densest known ellipsoid packings (i.e., 0.7707...). In addition, we study dense packings of clusters of pair-linked ring tori (i.e., Hopf links), which can possess much higher densities than corresponding packings consisting of unlinked tori. PMID:25353448

Gabbrielli, Ruggero; Jiao, Yang; Torquato, Salvatore

2014-02-01

149

Dense periodic packings of tori  

NASA Astrophysics Data System (ADS)

Dense packings of nonoverlapping bodies in three-dimensional Euclidean space R3 are useful models of the structure of a variety of many-particle systems that arise in the physical and biological sciences. Here we investigate the packing behavior of congruent ring tori in R3, which are multiply connected nonconvex bodies of genus 1, as well as horn and spindle tori. Specifically, we analytically construct a family of dense periodic packings of unlinked tori guided by the organizing principles originally devised for simply connected solid bodies [22 Torquato and Jiao, Phys. Rev. E 86, 011102 (2012), 10.1103/PhysRevE.86.011102]. We find that the horn tori as well as certain spindle and ring tori can achieve a packing density not only higher than that of spheres (i.e., ? /?18 =0.7404...) but also higher than the densest known ellipsoid packings (i.e., 0.7707...). In addition, we study dense packings of clusters of pair-linked ring tori (i.e., Hopf links), which can possess much higher densities than corresponding packings consisting of unlinked tori.

Gabbrielli, Ruggero; Jiao, Yang; Torquato, Salvatore

2014-02-01

150

Method for packing chromatographic beds  

DOEpatents

Column chromatography beds are packed through the application of static force. A slurry of the chromatography bed material and a non-viscous liquid is filled into the column plugged at one end, and allowed to settle. The column is transferred to a centrifuge, and centrifuged for a brief period of time to achieve a predetermined packing level, at a range generally of 100-5,000 gravities. Thereafter, the plug is removed, other fixtures may be secured, and the liquid is allowed to flow out through the bed. This results in an evenly packed bed, with no channeling or preferential flow characteristics.

Freeman, David H. (Potomac, MD); Angeles, Rosalie M. (Germantown, MD); Keller, Suzanne (Rockville, MD)

1991-01-01

151

Battery charger for a backup power circuit  

SciTech Connect

A battery pack-containing solid state circuit, normally in a standby condition, automatically applies battery-generated power to a multi-power requirement load a predetermined time period subsequent to detection of a malfunction in the load's normal power source. In switching to its power-applying state, the circuit disconnects the load from its malfunctioning power source and energizes the load at a level consistent with the battery pack capabilities. The circuit includes a unique fold-backcharacterized, overcurrent-protected inverter and a temperaturecompensated battery charger. A low battery voltage sensor exhibiting hysteresis characteristics inhibits operation of the circuit when the battery voltage drops below a predetermined level indicative of a discharge condition, the low voltage sensor continuing to inhibit operation of the circuit until a battery voltage charging input regains a level in excess of the predetermined level at which the discharge battery initially inhibited circuit operation. Restoration of normal power resets the circuit to a standby condition after a predetermined time period. The circuit finds particular application as an emergency power unit to effect lowering of an hydraulic elevator car and release of passengers therefrom.

Reynolds, W.R.

1983-05-03

152

Enabling Microliquid Chromatography by Microbead Packing of Microchannels  

NASA Technical Reports Server (NTRS)

The microbead packing is the critical element required in the success of on-chip microfabrication of critical microfluidic components for in-situ analysis and detection of chiral amino acids. In order for microliquid chromatography to occur, there must be a stationary phase medium within the microchannel that interacts with the analytes present within flowing fluid. The stationary phase media are the microbeads packed by the process discussed in this work. The purpose of the microliquid chromatography is to provide a lightweight, low-volume, and low-power element to separate amino acids and their chiral partners efficiently to understand better the origin of life. In order to densely pack microbeads into the microchannels, a liquid slurry of microbeads was created. Microbeads were extracted from a commercially available high-performance liquid chromatography column. The silica beads extracted were 5 microns in diameter, and had surface coating of phenyl-hexyl. These microbeads were mixed with a 200- proof ethanol solution to create a microbead slurry with the right viscosity for packing. A microfilter is placed at the outlet via of the microchannel and the slurry is injected, then withdrawn across a filter using modified syringes. After each injection, the channel is flushed with ethanol to enhance packing. This cycle is repeated numerous times to allow for a tightly packed channel of microbeads. Typical microbead packing occurs in the macroscale into tubes or channels by using highly pressurized systems. Moreover, these channels are typically long and straight without any turns or curves. On the other hand, this method of microbead packing is completed within a microchannel 75 micrometers in diameter. Moreover, the microbead packing is completed into a serpentine type microchannel, such that it maximizes microchannel length within a microchip. Doing so enhances the interactions of the analytes with the microbeads to separate efficiently amino acids and amino acid enantiomers.

Balvin, Manuel; Zheng, Yun

2013-01-01

153

Enabling Microliquid Chromatography by Microbead Packing of Microchannels  

NASA Technical Reports Server (NTRS)

The microbead packing is the critical element required in the success of on-chip microfabrication of critical microfluidic components for in-situ analysis and detection of chiral amino acids. In order for microliquid chromatography to occur, there must be a stationary phase medium within the microchannel that interacts with the analytes present within flowing fluid. The stationary phase media are the microbeads packed by the process discussed in this work. The purpose of the microliquid chromatography is to provide a lightweight, low-volume, and low-power element to separate amino acids and their chiral partners efficiently to understand better the origin of life. In order to densely pack microbeads into the microchannels, a liquid slurry of microbeads was created. Microbeads were extracted from a commercially available high-performance liquid chromatography column. The silica beads extracted were 5 microns in diameter, and had surface coating of phenyl-hexyl. These microbeads were mixed with a 200- proof ethanol solution to create a microbead slurry with the right viscosity for packing. A microfilter is placed at the outlet via of the microchannel and the slurry is injected, then withdrawn across a filter using modified syringes. After each injection, the channel is flushed with ethanol to enhance packing. This cycle is repeated numerous times to allow for a tightly packed channel of microbeads. Typical microbead packing occurs in the macroscale into tubes or channels by using highly pressurized systems. Moreover, these channels are typically long and straight without any turns or curves. On the other hand, this method of microbead packing is completed within a microchannel 75 micrometers in diameter. Moreover, the microbead packing is completed into a serpentine type microchannel, such that it maximizes microchannel length within a microchip. Doing so enhances the interactions of the analytes with the microbeads to separate efficiently amino acids and amino acid enantiomers.

Balvin, Manuel; Zheng, Yun

2014-01-01

154

A solid hydraulically amplified piezoelectric microvalve  

NASA Astrophysics Data System (ADS)

We report a piezoelectrically driven and hydraulically amplified axial polymer microvalve. The microvalve is normally open and is assembled primarily with stereolithographically fabricated polymer components. An incompressible elastomer is used as a solid hydraulic medium to convert the small axial displacement of a piezoelectric actuator into a large valve head stroke while maintaining a large blocking force. Also, the axial design of the microvalve enables densely packed valve arrays. One application of this microvalve is in pneumatic tactile displays, which operates against gas pressure up to approximately 90 kPa and switching speed between 1 and 200 Hz. The current valve design has a maximum static hydraulic amplification ratio of 5 at 30 V driving voltage and a maximum valve head stroke of 37 µm at 150 V. Under a 94.4 kPa differential pressure, the flow rate of the valve and the closing voltage measure are 785 mL min-1 and 150 V, respectively. The function of the microvalve as an on-off switch for a pneumatic microbubble tactile actuator is demonstrated.

Wu, Xiaosong; Kim, Seong-Hyok; Ji, Chang-Hyeon; Allen, Mark G.

2011-09-01

155

Hydraulic Fracturing Sand  

USGS Multimedia Gallery

Fine-grained silica sand is mixed with chemicals and water before being pumped into rock formations to prevent the newly created artificial fractures from closing after hydraulic fracturing is completed....

156

Empirical equations for some soil hydraulic properties  

Microsoft Academic Search

with a power function relating soil moisture and hydraulic conductivitymis used to derive a formula for the wetting front suction required by the Green-Ampt equation. Representative parameters for the moisture charac- teristic, the wetting front suction, and the sorptivity, a parameter in the infiltration equation derived by Philip (1957), are computed by using the desorption data of Holtan et al.

Roger B. Clapp; George M. Hornberger

1978-01-01

157

The crack tip region in hydraulic fracturing  

Microsoft Academic Search

We present analytical tip region solutions for fracture width and pressure when a power law fluid drives a plane strain fracture in an impermeable linear elastic solid. Our main result is an intermediate asymptotic solution in which the tip region stress is dominated by a singularity which is particular to the hydraulic fracturing problem. Moreover this singularity is weaker than

J. Desroches; E. Detournay; B. Lenoach; P. Papanastasiou; J. R. A. Pearson; M. Thiercelin; A. Cheng

1994-01-01

158

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT IX, AUTOMATIC TRANSMISSIONS--HYDRAULIC SYSTEM (PART I).  

ERIC Educational Resources Information Center

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…

Human Engineering Inst., Cleveland, OH.

159

Free-piston regenerative hot gas hydraulic engine  

NASA Technical Reports Server (NTRS)

A displacer piston which is driven pneumatically by a high-pressure or low-pressure gas is included in a free-piston regenerative hydraulic engine. Actuation of the displacer piston circulates the working fluid through a heater, a regenerator and a cooler. The present invention includes an inertial mass such as a piston or a hydraulic fluid column to effectively store and supply energy during portions of the cycle. Power is transmitted from the working fluid to a hydraulic fluid across a diaphragm or lightweight piston to achieve a hydraulic power out-put. The displacer piston of the present invention may be driven pneumatically, hydraulically or electromagnetically. In addition, the displacer piston and the inertial mass of the present invention may be positioned on the same side of the diaphragm member or may be separated by the diaphragm member.

Beremand, D. G. (inventor)

1980-01-01

160

Packing microstructure and local density variations of experimental and computational pebble beds  

SciTech Connect

In pebble bed type nuclear reactors the fuel is contained in graphite pebbles, which form a randomly stacked bed with a non-uniform packing density. These variations can influence local coolant flow and power density and are a possible cause of hotspots. To analyse local density variations computational methods are needed that can generate randomly stacked pebble beds with a realistic packing structure on a pebble-to-pebble level. We first compare various properties of the local packing structure of a computed bed with those of an image made using computer aided X-ray tomography, looking at properties in the bulk of the bed and near the wall separately. Especially for the bulk of the bed, properties of the computed bed show good comparison with the scanned bed and with literature, giving confidence our method generates beds with realistic packing microstructure. Results also show the packing structure is different near the wall than in the bulk of the bed, with pebbles near the wall forming ordered layers similar to hexagonal close packing. Next, variations in the local packing density are investigated by comparing probability density functions of the packing fraction of small clusters of pebbles throughout the bed. Especially near the wall large variations in local packing fractions exists, with a higher probability for both clusters of pebbles with low (<0.6) and high (>0.65) packing fraction, which could significantly affect flow rates and, together with higher power densities, could result in hotspots. (authors)

Auwerda, G. J.; Kloosterman, J. L.; Lathouwers, D.; Van Der Hagen, T. H. J. J. [Delft Univ. of Technology, Mekelweg 15, 2629 JB, Delft (Netherlands)

2012-07-01

161

7 CFR 51.1311 - Packing.  

Code of Federal Regulations, 2011 CFR

... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

2011-01-01

162

7 CFR 51.1311 - Packing.  

Code of Federal Regulations, 2013 CFR

... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

2013-01-01

163

7 CFR 51.1270 - Packing.  

Code of Federal Regulations, 2012 CFR

...United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

2012-01-01

164

7 CFR 51.1270 - Packing.  

Code of Federal Regulations, 2014 CFR

...United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

2014-01-01

165

7 CFR 51.1311 - Packing.  

Code of Federal Regulations, 2010 CFR

... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

2010-01-01

166

7 CFR 51.1311 - Packing.  

Code of Federal Regulations, 2014 CFR

... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

2014-01-01

167

7 CFR 51.1311 - Packing.  

Code of Federal Regulations, 2012 CFR

... United States Standards for Winter Pears 1 Standard Pack § 51.1311 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

2012-01-01

168

7 CFR 51.1270 - Packing.  

Code of Federal Regulations, 2013 CFR

...United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1270 Packing...Each package shall be packed so that the pears in the shown face shall be reasonably...of the contents of the package. (b) Pears packed in any container shall be...

2013-01-01

169

Steady state thermal hydraulic analysis of hydride fueled BWRs  

E-print Network

(cont.) Since the results obtained in the main body of the analysis account only for thermal-hydraulic constraints, an estimate of the power reduction due to the application of neutronic constraints is also performed. This ...

Ferroni, Paolo, Ph. D. Massachusetts Institute of Technology

2006-01-01

170

Molecular packing and packing defects in helical membrane proteins.  

PubMed

The packing of helices spanning lipid bilayers is crucial for the stability and function of alpha-helical membrane proteins. Using a modified Voronoi procedure, we calculated packing densities for helix-helix contacts in membrane spanning domains. Our results show that the transmembrane helices of protein channels and transporters are significantly more loosely packed compared with helices in globular proteins. The observed packing deficiencies of these membrane proteins are also reflected by a higher amount of cavities at functionally important sites. The cavities positioned along the gated pores of membrane channels and transporters are noticeably lined by polar amino acids that should be exposed to the aqueous medium when the protein is in the open state. In contrast, nonpolar amino acids surround the cavities in those protein regions where large rearrangements are supposed to take place, as near the hinge regions of transporters or at restriction sites of protein channels. We presume that the observed deficiencies of helix-helix packing are essential for the helical mobility that sustains the function of many membrane protein channels and transporters. PMID:15556989

Hildebrand, Peter Werner; Rother, Kristian; Goede, Andrean; Preissner, Robert; Frömmel, Cornelius

2005-03-01

171

TU Delft: Hydraulic Engineering  

NSDL National Science Digital Library

Given the Dutch reputation for water management, it's no surprise that one of their leading technical institutes, The Technische Universiteit Delft, offers a program in Hydraulic Engineering. The website, in both Dutch and English, describes their program as an attempt "to bridge the gap between basic sciences (fluid mechanics and soil mechanics in particular) and practical engineering applications in the design, construction, maintenance, management and eventually the demolition of hydraulic structures." The Education section of the website posts MSc theses completed by their students. The research section describes current and recently completed research projects and includes a listing of publications, some of which are available to download. The website also has a link to a Hydraulic Engineering portal, which offers various publication databases (some in Dutch only), and the Civil Engineering Knowledge Centre, which provides library access and discussion forums for students and staff of Civil Engineering.

172

Safety and efficiency conflicts in hydraulic architecture: scaling from tissues to trees  

Microsoft Academic Search

Tree hydraulic architecture exhibits patterns that propagate from tissue to tree scales. A challenge is to make sense of these patterns in terms of trade-offs and adaptations. The universal trend for conduits per area to decrease with increasing conduit diameter below the theoretical packing limit may reflect the compromise between maximizing the area for conduction versus mechanical support and storage.

JOHN S. SPERRY; FREDERICK C. MEINZER; KATHERINE A. McCULLOH

2008-01-01

173

Hydraulics of wells  

USGS Publications Warehouse

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.

McLaughlin, Thad G.

1955-01-01

174

What Is Hydraulic Fracturing?  

NSDL National Science Digital Library

Hydraulic fracturing is a process used in nine out of 10 natural gas wells in the United States, where millions of gallons of water, sand and chemicals are pumped underground to break apart the rock and release the gas. Scientists are worried that the chemicals used in fracturing may pose a threat either underground or when waste fluids are handled and sometimes spilled on the surface. This poster presentation illustrates the under surface process of hydraulic fracking and the distribution flow to the market.

2012-01-01

175

[Electroflotation packing of mycelial wastes].  

PubMed

Data on testing a pilot plant for electroflotative packing of mycelial wastes are presented. Both the mycelial wastes and their mixtures were used. Concentration of dry substances raged from 3.5 to 131 g/l. The process was performed with varying flow density and consumption rate of the liquid supplied to the plant. Insoluble magnetite and ruthenium oxide anodes were used. The moister content in the packed phase was 81-97.5 per cent. The study provided specification of the process technological parameters and investigation of the flotator hydroulic characteristics. PMID:2751387

Nikolaev, V B; Karpukhin, V F; Zav'ialova, E V; Faingol'd, Z L

1989-04-01

176

Geostatistical inference of hydraulic conductivity and dispersivities from hydraulic heads and tracer data  

E-print Network

Geostatistical inference of hydraulic conductivity and dispersivities from hydraulic heads; accepted 25 April 2006; published 10 August 2006. [1] In groundwater, hydraulic heads and solute arrival times depend primarily on the hydraulic conductivity field and hydraulic boundary conditions. The spread

Cirpka, Olaf Arie

177

Laboratory Determination of Hydraulic Conductivity  

NSDL National Science Digital Library

From D.B. McWhorterand D. K. Sunda's 1977 Ground-Water Hydrology and Hydraulics, this two page excerpt outlines and details Laboratory Determination of Hydraulic Conductivity. Here, visitors will find illustrations and formula to understand the concept.

178

Determining the Porosity and Saturated Hydraulic Conductivity of Binary Mixtures  

SciTech Connect

Gravels and coarse sands make up significant portions of some environmentally important sediments, while the hydraulic properties of the sediments are typically obtained in the laboratory using only the fine fraction (e.g., <2 mm or 4.75 mm). Researchers have found that the content of gravel has significant impacts on the hydraulic properties of the bulk soils. Laboratory experiments were conducted to measure the porosity and the saturated hydraulic conductivity of binary mixtures with different fractions of coarse and fine components. We proposed a mixing-coefficient model to estimate the porosity and a power-averaging method to determine the effective particle diameter and further to predict the saturated hydraulic conductivity of binary mixtures. The proposed methods could well estimate the porosity and saturated hydraulic conductivity of the binary mixtures for the full range of gravel contents and was successfully applied to two data sets in the literature.

Zhang, Z. F.; Ward, Anderson L.; Keller, Jason M.

2009-09-27

179

Determining the Porosity and Saturated Hydraulic Conductivity of Binary Mixtures  

SciTech Connect

Gravels and coarse sands make up significant portions of some environmentally important sediments, while the hydraulic properties of the sediments are typically obtained in the laboratory using only the fine fraction (e.g., <2 mm or 4.75 mm). Researchers have found that the content of gravel has significant impacts on the hydraulic properties of the bulk soils. Laboratory experiments were conducted to measure the porosity and the saturated hydraulic conductivity of binary mixtures with different fractions of coarse and fine components. We proposed a mixing-coefficient model to estimate the porosity and a power-averaging method to determine the effective particle diameter and further to predict the saturated hydraulic conductivity of binary mixtures. The proposed methods could well estimate the porosity and saturated hydraulic conductivity of the binary mixtures for the full range of gravel contents and was successfully applied to two data sets in the literature.

Zhang, Z. F.; Ward, Anderson L.; Keller, Jason M.

2011-02-14

180

Efficient algorithms for orthogonal packing problems  

NASA Astrophysics Data System (ADS)

The NP complete problem of the orthogonal packing of objects of arbitrary dimension is considered in the general form. A new model for representing objects in containers is proposed that ensures the fast design of an orthogonal packing. New heuristics for the placement of orthogonal packing are proposed. A single-pass heuristic algorithm and a multimethod genetic algorithm are developed that optimize an orthogonal packing solution by increasing the packing density. Numerical experiments for two- and three-dimensional orthogonal packing problems are performed.

Chekanin, A. V.; Chekanin, V. A.

2013-10-01

181

Hydroinformatics at Delft Hydraulics  

Microsoft Academic Search

Hydroinformatics represents a technological challenge for a research and consultancy organisation such as DELFT HYDRAULICS. Building problem-solving systems by combining numerical models with computer technologies such as databases, geographical information systems (GIS), visualization systems, artificial intelligence and intelligent user interfaces, is only part of the work. The other part is quality control: ensuring that the results obtained with hydroinformatics systems

H. J. Van Zuylen; D. P. Dee; Ir. A. E. Mynett; G. S. Rodenhuis; Ir. J. R. Moll; Ir. H. J. M. Ogink; Ir. H. V. D. Most; Ir. H. Gerritsen; G. K. Verboom

1994-01-01

182

Water Treatment Technology - Hydraulics.  

ERIC Educational Resources Information Center

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…

Ross-Harrington, Melinda; Kincaid, G. David

183

Hydraulic Shutdown Monitor  

NASA Technical Reports Server (NTRS)

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.

Fleming, S. T.; Harrington, D. B.

1986-01-01

184

Integration in Hydraulics.  

ERIC Educational Resources Information Center

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…

Sworder, Steven C.

185

Evaluation of the thermal-hydraulic response and fuel rod thermal and mechanical deformation behavior during the power burst facility test LOC-3. [PWR  

Microsoft Academic Search

An evaluation of the results from the LOC-3 nuclear blowdown test conducted in the Power Burst Facility is presented. The test objective was to examine fuel and cladding behavior during a postulated cold leg break accident in a pressurized water reactor (PWR). Separate effects of rod internal pressure and the degree of irradiation were investigated in the four-rod test. Extensive

T. R. Yackle; P. E. MacDonald; J. M. Broughton

1980-01-01

186

Evaluation of the thermal-hydraulic and fuel rod thermal and mechanical deformation behavior during the first Power Burst Facility nuclear blowdown tests  

Microsoft Academic Search

A preliminary evaluation was made of the results from the LOC-11 nuclar blowdown tests conducted in the Power Burst Facility. The objective of the LOC-11 tests was to measure the thermal and mechanical deformation behavior of pressurized and unpressurized fuel rods exposed to a blowdown (coolant depressurization) similar to that expected in a pressurized water reactor (PWR) during a hypothesized

P. E. MacDonald; J. M. Broughton; J. W. Spore

1979-01-01

187

Packing the PLSS  

NASA Technical Reports Server (NTRS)

NASA Engineers design spacesuits for ultimate protection and functionality in the extreme environment of space. The spacesuit is often referred to as a "personal spacecraft" because it provides the astronaut with everything he or she needs to survive and work in space outside of the vehicle or habitat. The systems within the spacesuit include the pressure garment system (PGS), the Portable Life Support System (PLSS), and the power, avionics, and software (PAS) system. These elements are necessary to protect crewmembers and allow them to work effectively in the pressure and temperature extremes of space environments. Development of the spacesuit system is necessary to support future human extravehicular exploration activities to Lunar, Martian, microgravity, and possibly other space destinations. Although all the systems that makeup the space suit are important, the PLSS is one of the most complex. The PLSS provides the life support needed by the astronaut and consists of the oxygen (O2) subsystem, ventilation subsystem, and thermal control subsystem. Within each subsystem, there are many different components, a few of which are explained as follows. The oxygen tanks hold the oxygen that the crewmember uses to breath and pressurizes the suit. The primary oxygen tank is responsible during normal operations and the secondary oxygen tank kicks on in the case of an emergency. The Rapid Cycle Amine (RCA) canister is used to remove the carbon dioxide (CO2) and extra humidity in the crewmember's ventilation/breathing gas. The fan moves the oxygen around the suit. Suit Water Membrane Evaporator (SWME) is used within the thermal control loop to cool the water that is used to maintain a comfortable temperature for both the crew member and the other equipment inside the suit. Another component is the battery, which supplies the power needed to operate all these and the many other pieces. The battery is one of the biggest and heavies components within the PLSS. These are just a few of the components that encompass the PLSS. Each component has a weight and a certain volume that the NASA Engineers must take into account when building the PLSS, because the weight and volumes affect the crewmembers center of gravity (CG). [See the Notes Section for the link to an Apollo video that demonstrates the issues some of the crewmembers had picking up tools and dealing with center of gravity/tools on the surface of the Moon.] In this activity, students will simulate engineering design techniques that NASA Engineers and Designers are currently implementing to configuring the components within the PLSS. Through testing, students will consider the comfort, mobility, and center of gravity for their test subjects and how that changes after adjusting the placement of their simulated PLSS components.

Jennings, Mallory

2011-01-01

188

Viscous Hydraulic Jumps Submitted by  

E-print Network

Viscous Hydraulic Jumps Submitted by Jeffrey M. Aristoff, Jeffrey D. Leblanc, Annette E. Hosoi, and John W. M. Bush, Massachusetts Institute of Technology We examine the form of the viscous hydraulic of height 2­10 mm. Elegaard et al.1 first demonstrated that the axial symme- try of the viscous hydraulic

Bush, John W.M.

189

Calculator programs determine drilling hydraulics  

Microsoft Academic Search

Two TI-59 programs were prepared for the calculation of drilling hydraulics as set forth in the Hughes Tool Co. publication, Practical Hydraulics. One presents the stepwise determination of drill string pressure drop while the second, to be published in a future issue, calculates jet area, jet velocity and impact force along with bit pressure drop and hydraulic horsepower. Another section

Landry

1987-01-01

190

Calculator programs determine drilling hydraulics  

Microsoft Academic Search

This paper describes Hydraulics II, which is prepared for the calculation of bit hydraulics and pump performance on the TI-59 using a PC-100C printer. The operator is prompted for the required input data with a printed register number and an abbreviated title. Output is printed and labeled. As in Hydraulics I, three magnetic cards are required, two for the program

Landry

1987-01-01

191

Computer simulation of hydraulic fractures  

Microsoft Academic Search

We provide a brief historical background of the development of hydraulic fracturing models for use in the petroleum and other industries. We discuss scaling laws and the propagation regimes that control the growth of hydraulic fractures from the laboratory to the field scale. We introduce the mathematical equations and boundary conditions that govern the hydraulic fracturing process, and discuss numerical

J. Adachi; E. Siebrits; A. Peirce; J. Desroches

2007-01-01

192

Water Resources: Hydraulics and Hydrology  

E-print Network

Water Resources: Hydraulics and Hydrology Interview with Margaret S. Petersen #12;This manuscript RESOURCES: HYDRAULICS AND HYDROLOGY #12;Approved for public release distribution IS unlimited. #12;Preface The United States Army Corps of Engineers significantly contributed to hydraulic and hydrologic engineering

US Army Corps of Engineers

193

Students & Mental Health Resource Pack  

E-print Network

Students & Mental Health Resource Pack Produced by - www.rethink.org/at-ease/ SHEFFIELD EARLY is severe mental illness? 1.4 Treatment and prognosis What is mental health awareness? 2.1 Introduction 2 for students with experience of mental health problems 5.1 Introduction 5.2 Pre-entry guidance for students 5

Stevenson, Mark

194

Oil Spill! ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-21

195

Wiggling Worms ClassPack  

NSDL National Science Digital Library

Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

2010-04-23

196

Packing Schemes for Gang Scheduling  

Microsoft Academic Search

. Jobs that do not require all processors in the system can bepacked together for gang scheduling. We examine accounting traces fromseveral parallel computers to show that indeed many jobs have small sizesand can be packed together. We then formulate a number of such packingalgorithms, and evaluate their effectiveness using simulations based onour workload study. The results are that two

Dror G. Feitelson

1996-01-01

197

Wire and Packing Tape Sandwiches  

ERIC Educational Resources Information Center

In this article, the author describes how students can combine craft wire with clear packing tape to create a two-dimensional design that can be bent and twisted to create a three-dimensional form. Students sandwich wire designs between two layers of tape. (Contains 1 online resource.)

Rabinowitz, Sandy

2009-01-01

198

Kinetic model for an up-flow anaerobic packed bed bioreactor: Dairy wastewater treatment  

Microsoft Academic Search

Kinetic studies of anaerobic digestion process of cheese whey were conducted in a pilot-scale up-flow anaerobic packed bed bioreactor (UAPB). An influent COD concentration of 59419 mg\\/l was utilized at steady state condition. Logistic and Monod kinetic models were employed to describe microbial activities of cheese whey in an anaerobic digester. The hydraulic retention times (HRT) in the range of

G. D. Najafpour; M. Tajallipour; M. Komeili; M. Mohammadi

199

Sorption of antimicrobial agents in blow-fill-seal packs.  

PubMed

The present work studies the interaction of methyl paraben (MPB) and propyl paraben (PPB), two widely used antimicrobial agents in multi-dose ophthalmic formulations, with 5?mL, low density polyethylene (LDPE) and polypropylene (PP) blow-fill-seal (BFS) packs, by subjecting the systems to accelerated stability conditions of 40°C/25% RH. The effect of pH, paraben concentration, and relative humidity (RH) on the sorption loss of both the parabens was studied. Additionally, the effects of buffer species and buffer strength on MPB sorption were studied. LDPE packs showed significantly higher loss compared to PP packs which showed < 5% loss in all cases. PPB showed a significantly higher loss (40-50%) than MPB (9-16%) in LDPE. pH (3.0, 5.0, 7.0) did not have a statistically significant effect on sorption. However, concentration, humidity and buffer at pH 7 affected paraben sorption. The application of the power law suggested that the MPB followed non-Fickian diffusion while PPB showed non-Fickian to Case II diffusion in LDPE packs. In conclusion, caution should be exercised while using parabens in LDPE BFS packs because substantial losses of the antimicrobial agent during the shelf-life can compromise the preservative effectiveness against 'in-use' contamination. PMID:20887236

Amin, Aeshna; Chauhan, Sateesh; Dare, Manish; Bansal, Arvind Kumar

2012-01-01

200

7 CFR 958.16 - Pack.  

Code of Federal Regulations, 2012 CFR

...Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ONIONS GROWN IN CERTAIN DESIGNATED COUNTIES IN IDAHO, AND MALHEUR...Definitions § 958.16 Pack. Pack means a quantity of onions in any type of container and which falls within specific...

2012-01-01

201

7 CFR 945.15 - Pack.  

Code of Federal Regulations, 2010 CFR

...and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN CERTAIN DESIGNATED COUNTIES IN IDAHO, AND MALHEUR COUNTY, OREGON Order Regulating Handling Definitions § 945.15 Pack. Pack means a quantity...

2010-01-01

202

7 CFR 966.11 - Pack.  

Code of Federal Regulations, 2010 CFR

...Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating... Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States...

2010-01-01

203

7 CFR 966.11 - Pack.  

Code of Federal Regulations, 2014 CFR

...NUTS), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating... Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States...

2014-01-01

204

7 CFR 966.11 - Pack.  

Code of Federal Regulations, 2013 CFR

...NUTS), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating... Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States...

2013-01-01

205

7 CFR 966.11 - Pack.  

Code of Federal Regulations, 2012 CFR

...Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating... Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States...

2012-01-01

206

7 CFR 966.11 - Pack.  

Code of Federal Regulations, 2011 CFR

...Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating... Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States...

2011-01-01

207

Nonlinear elastic stress response in granular packings.  

PubMed

We study the nonlinear elastic response of a two-dimensional material to a localized boundary force, with the particular goal of understanding the differences observed between isotropic granular materials and those with hexagonal anisotropy. Corrections to the classical Boussinesq result for the stresses in an infinite half space of a linear, isotropic material are developed in a power series in inverse distance from the point of application of the force. The breakdown of continuum theory on scales of order of the grain size is modeled with phenomenological parameters characterizing the strengths of induced multipoles near the point of application of the external force. We find that the data of Geng [Phys. Rev. Lett. 87, 035506 (2001)] on isotropic and hexagonal packings of photoelastic grains can be fitted within this framework. Fitting the hexagonal packings requires a choice of elastic coefficients with hexagonal anisotropy stronger than that of a simple ball-and-spring model. For both the isotropic and hexagonal cases, induced dipole and quadrupole terms produce propagation of stresses away from the vertical direction over short distances. The scale over which such propagation occurs is significantly enhanced by the nonlinearities that generate hexagonal anisotropy. PMID:18517366

Tighe, Brian P; Socolar, Joshua E S

2008-03-01

208

On the kinetics of pack aluminization  

NASA Technical Reports Server (NTRS)

A theory of pack aluminization has been formulated by combining gaseous and solid-state diffusion rates. This theory relates the surface composition of the coating and therefore, in principle, the phase morphology and the growth rate of the coating, to pack operating parameters such as pack aluminum density, type of activator, temperature and others. Experimental data on the aluminization of unalloyed nickel in pure aluminum packs obtained to date are in good agreement with the predictions of the theory.

Gupta, B. K.; Sarkhel, A. K.; Seigle, L. L.

1975-01-01

209

Hydraulic manipulator research at ORNL  

SciTech Connect

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.

Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States); Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States)

1997-03-01

210

Evaluation of the thermal-hydraulic response and fuel rod thermal and mechanical deformation behavior during the power burst facility test LOC-3. [PWR  

SciTech Connect

An evaluation of the results from the LOC-3 nuclear blowdown test conducted in the Power Burst Facility is presented. The test objective was to examine fuel and cladding behavior during a postulated cold leg break accident in a pressurized water reactor (PWR). Separate effects of rod internal pressure and the degree of irradiation were investigated in the four-rod test. Extensive cladding deformation (ballooning) and failure occurred during blowdown. The deformation of the low and high pressure rods was similar; however, the previously irradiated test rod deformed to a greater extent than a similar fresh rod exposed to identical system conditions.

Yackle, T.R.; MacDonald, P.E.; Broughton, J.M.

1980-01-01

211

On the dynamics of hydraulic lines supplying servosystems  

NASA Astrophysics Data System (ADS)

Measures for achieving an almost quiescent state of hydraulic power supply pressure are outlined. Models for hydraulic pipelines supplying hydraulic control systems, which integrate dynamic behavior of the pipelines, the pressure control valve, or pressure controlled variable displacement pump, gas accumulators, and Helmholtz resonators are developed. Experiments show that pressure fluctuations due to pump flow pulsations are suppressed by a selective filter or by a small gas accumulator. Helmholtz resonator is most effective for eliminating one specific frequency of pump flow pulsation. A gas accumulator close to the pump suppresses pulsations in a wide frequency range. Pressure fluctuations due to the varying servomotor oil consumption are suppressed by an accumulator near the servovalve.

Ham, A. A.

1982-01-01

212

CIRCLE PACKING AND DISCRETE ANALYTIC FUNCTION THEORY  

E-print Network

CIRCLE PACKING AND DISCRETE ANALYTIC FUNCTION THEORY KENNETH STEPHENSON Abstract. Circle packings | con#12;gurations of circles with speci#12;ed patterns of tangency | came to prominence with analysts that one can fairly claim that circle packing provides a discrete analytic function theory. There are two

Stephenson, Kenneth

213

CIRCLE PACKING BIBLIOGRAPHY AS OF SEPTEMBER 2005  

E-print Network

CIRCLE PACKING BIBLIOGRAPHY AS OF SEPTEMBER 2005 MAINTAINED BY KENNETH STEPHENSON The term circle packing here refers to con#12;gurations of circles with speci#12;ed pat- terns of tangency. The central with density and coverings using sphere's of given radii.) The software package CirclePack for creating

Stephenson, Kenneth

214

Climate Change Action Pack Climate & Habitats  

E-print Network

Climate Change Action Pack Climate & Habitats B A C K G R O U DN C H E C K ! Habitat, Food, Water the potential to affect plants,animals and humans around the globe. #12;Climate Change Action Pack 158 Habitat out in shapes of hills, waves, leaves, and berries. #12;Climate Change Action Pack 159 PROCEDURE

Gunawardena, Arunika

215

Hydraulically actuated artificial muscles  

NASA Astrophysics Data System (ADS)

Hydraulic Artificial Muscles (HAMs) consisting of a polymer tube constrained by a nylon mesh are presented in this paper. Despite the actuation mechanism being similar to its popular counterpart, which are pneumatically actuated (PAM), HAMs have not been studied in depth. HAMs offer the advantage of compliance, large force to weight ratio, low maintenance, and low cost over traditional hydraulic cylinders. Muscle characterization for isometric and isobaric tests are discussed and compared to PAMs. A model incorporating the effect of mesh angle and friction have also been developed. In addition, differential swelling of the muscle on actuation has also been included in the model. An application of lab fabricated HAMs for a meso-scale robotic system is also presented.

Meller, M. A.; Tiwari, R.; Wajcs, K. B.; Moses, C.; Reveles, I.; Garcia, E.

2012-04-01

216

Remotely Adjustable Hydraulic Pump  

NASA Technical Reports Server (NTRS)

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.

Kouns, H. H.; Gardner, L. D.

1987-01-01

217

Electro-modulated control of supply pressure in hydraulic systems  

NASA Astrophysics Data System (ADS)

After noting the hydraulic power requirements of representative military aircraft, attention is given to the inefficiencies of the higher-pressure systems being considered for high horsepower and to the approaches available for superior management of high pressure/horsepower requirements. The benefits obtainable through variable-pressure system designs are illustrated; such systems gain a beneficial synergy from the combination of hydraulics and electronics.

Lawhead, Paul

218

Cell aggregation: Packing soft grains  

NASA Astrophysics Data System (ADS)

Cellular aggregates may be considered as collections of membrane enclosed units with a pressure difference between the internal and external liquid phases. Cells are kept together by membrane adhesion and/or confined space compression. Pattern formation and, in particular, intercellular spacing have important roles in controlling solvent diffusion within such aggregates. A physical approach is used to study generic aspects of cellular packings in a confined space. Average material properties are derived from the free energy. The appearance of penetrating intercellular void channels is found to be critically governed by the cell wall adhesion mechanisms during the formation of dense aggregates. A fully relaxed aggregate efficiently hinders solvent diffusion at high hydrostatic pressures, while a small fraction (˜0.1) of adhesion related packing frustration is sufficient for breaking such a blockage even at high a pressure.

Åström, J. A.; Karttunen, M.

2006-06-01

219

Cell aggregation: packing soft grains.  

PubMed

Cellular aggregates may be considered as collections of membrane enclosed units with a pressure difference between the internal and external liquid phases. Cells are kept together by membrane adhesion and/or confined space compression. Pattern formation and, in particular, intercellular spacing have important roles in controlling solvent diffusion within such aggregates. A physical approach is used to study generic aspects of cellular packings in a confined space. Average material properties are derived from the free energy. The appearance of penetrating intercellular void channels is found to be critically governed by the cell wall adhesion mechanisms during the formation of dense aggregates. A fully relaxed aggregate efficiently hinders solvent diffusion at high hydrostatic pressures, while a small fraction (approximately 0.1) of adhesion related packing frustration is sufficient for breaking such a blockage even at high a pressure. PMID:16906885

Aström, J A; Karttunen, M

2006-06-01

220

Planet packing in circumbinary systems  

NASA Astrophysics Data System (ADS)

The recent discovery of planets orbiting main-sequence binaries will provide crucial constraints for theories of binary and planet formation. The formation pathway for these planets is complicated by uncertainties in the formation mechanism of the host stars. In this paper, we compare the dynamical states of single- and binary-star planetary systems. Specifically, we pose two questions: (1) What does it mean for a circumbinary system to be dynamically packed? (2) How many systems are required to differentiate between a population of packed or sparse planets? We determine when circumbinary systems become dynamically unstable as a function of the separation between the host-stars and the inner planet, and the first and second planets. We show that these represent unique stability constraints compared to single-star systems. We find that although the existing Kepler data is insufficient to distinguish between a population of packed or sparse circumbinary systems, a more thorough study of circumbinary Transit Timing Variations (TTVs) combined with an order of magnitude increase in the number of systems may prove conclusive. Future space missions such as TESS provide the best opportunity for increasing the sample size.

Kratter, Kaitlin M.; Shannon, Andrew

2014-02-01

221

Battery pack circuit design for safety and protection  

SciTech Connect

Do our fast-paced lifestyles drive new technology, or is new technology partly to blame for continuing to increase the pace of our lifestyles? We want to be connected and productive - or entertained - even during our traditional times of leisure and recreation. Our tools for connectivity and productivity - and our toys for entertainment - support us by continuing to become smaller, lighter and more mobile, even as functionality increases. This drive toward increasing portability, mobility and functionality has had many interesting results. One result is that high-energy battery packs are becoming pervasive in our professional and personal lives. But the high power-delivery and energy-storage capabilities of packs for these power-hungry devices generally remain invisible to end-users. In reality, most packs have the potential not only for damaging themselves, but also for imposing damage on their surroundings, even if used exclusively in accordance with manufacturers` instructions. And newer battery technologies that offer longer runtimes or less weight can pose higher risks. This paper compares and contrasts the characteristics of various safety practices and devices used in designing and assembling high-energy battery packs.

Dewey, M.; Chandler, D.; Tamura, A. [Raychem Corp., Menlo Park, CA (United States)

1995-12-31

222

Adhesive Loose Packings of Small Particles  

E-print Network

We explore adhesive loose packings of dry small spherical particles of micrometer size using 3D discrete-element simulations with adhesive contact mechanics. A dimensionless adhesion parameter ($Ad$) successfully combines the effects of particle velocities, sizes and the work of adhesion, identifying a universal regime of adhesive packings for $Ad>1$. The structural properties of the packings in this regime are well described by an ensemble approach based on a coarse-grained volume function that includes correlations between bulk and contact spheres. Our theoretical and numerical results predict: (i) An equation of state for adhesive loose packings that appears as a continuation from the frictionless random close packing (RCP) point in the jamming phase diagram; (ii) The existence of a maximal loose packing point at the coordination number $Z=2$ and packing fraction $\\phi=1/2^{3}$. Our results highlight that adhesion leads to a universal packing regime at packing fractions much smaller than the random loose packing, which can be described within a statistical mechanical framework. We present a general phase diagram of jammed matter comprising frictionless, frictional, adhesive as well as non-spherical particles, providing a classification of packings in terms of their continuation from the spherical frictionless RCP.

Wenwei Liu; Shuiqing Li; Adrian Baule; Hernán A. Makse

2014-10-08

223

Kinetics of pack aluminization of nickel  

NASA Technical Reports Server (NTRS)

The kinetics of pack aluminization of unalloyed nickel in packs of varying aluminum activity with various halide activators were studied. Surface compositions of the coatings as functions of time, temperature, and pack composition were obtained in order to establish the boundary conditions for diffusion in the system. The structure of the packs was also examined in order to clarify the mechanism of aluminum transport. The results indicate that the kinetics of pack aluminization are controlled jointly by gas diffusion in the pack and solid diffusion in the coating. Levine and Caves' model for gas diffusion was combined with calculations of rates of diffusion in the solid to formulate a more complete theory for the kinetics of pack aluminization.

Seigle, L. L.; Gupta, B. K.; Shankar, R.; Sarkhel, A. K.

1978-01-01

224

Engine end for a downhole hydraulically actuated pump assembly  

Microsoft Academic Search

This patent describes a hydraulically actuated downhole pump assembly for producing a well when power fluid is pumped thereto whereupon produced fluid admixed with spent power fluid is returned therefrom. It comprises: the engine end has an engine piston connected to actuate the pump end; the engine end has an annular outer housing, the annular valve element moves axially between

Roeder

1992-01-01

225

A generalized multiscaling model for hydraulic geometry (HG)  

Microsoft Academic Search

Power law relationships between channel geometry (width, mean depth, mean velocity and cross-sectional area) and discharge, known as hydraulic geometry (HG), have long been explored in hydrology and geomorphology. The at-station exponents of these power laws for below bankfull conditions have been found to depend on the contributing area (scale) leading to proposing a multiscaling model for HG (Dodov and

B. Dodov; E. Foufoula-Georgiou

2003-01-01

226

Fluctuations, structure factor and polytetrahedra in random packings of sticky hard spheres  

E-print Network

Sequentially-built random sphere-packings have been numerically studied in the packing fraction interval $0.329 structure factors $S(Q)$ of the aggregates. Among various parameters (Voronoi tessellation, contact coordination number distribution,...), fluctuations were quantitatively evaluated by the direct evaluation of the fluctuations of the local sphere number density, which appears to follow a power law. The FWHM of the Voronoi cells volume shows a regular variation over the whole packing fraction range. Dirac peaks appear on the pair correlation function as the packing fraction of the aggregates decreases, indicating the growth of larger and larger polytetrahedra, which manifest in two ways on the structure factor, at low and large $Q$values. These low PF aggregates have a composite structure made of regular polytetrahedra embedded in a more disordered matrix. Incidentally, the irregularity index of the building tetrahedron appears as a better parameter than the packing fraction to describe various features of the aggregates structure.

Marc Bletry; Jean Bletry

2014-09-08

227

Calculator programs determine drilling hydraulics  

SciTech Connect

Two TI-59 programs were prepared for the calculation of drilling hydraulics as set forth in the Hughes Tool Co. publication, Practical Hydraulics. One presents the stepwise determination of drill string pressure drop while the second, to be published in a future issue, calculates jet area, jet velocity and impact force along with bit pressure drop and hydraulic horsepower. Another section of the second program considers pump mechanics, calculating the required strokes per minute to attain a specific circulating rate, or the circulation that would result from a specific pump speed. Hydraulic horsepower of the pump is then calculated from this rate and a maximum pump pressure.

Landry, W.E.

1987-05-01

228

Hydraulic mining method  

DOEpatents

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.

Huffman, Lester H. (Kent, WA); Knoke, Gerald S. (Kent, WA)

1985-08-20

229

Evaluation of an aerobic submerged filter packed with volcanic scoria.  

PubMed

An aerobic submerged filter (ASF) using volcanic scoria stones as packing media was evaluated. The wastewater used was a mixture of sewage with sugar to obtain organic matter concentrations between 28 and 3230 mg CODt/L, hydraulic rates up to 2.88 m3/m2 d and organic loading rates between 0.45 and 9.4 kg CODt/m3 d. The system removed 80% of CODt as average for organic loading rates between 0.45 and 3 kg CODt/m3 d and 54% at the higher rate (9.4 kg CODt/m3 d). It was not necessary to backwash the filters, a negligible pressure drop and a good biomass attachment in the volcanic scoria stones was observed. Nitrification and organic matter biodegradation were carried out simultaneously with a nitrate production of 90% up to 1.7kgCODt/m3 d. Tracer studies revealed a completed mixed hydraulic pattern which was not affected by the presence of biomass. PMID:17590330

Morgan-Sagastume, J M; Noyola, A

2008-05-01

230

Packed, Printable, and Polymorphic Return-Oriented Programming  

Microsoft Academic Search

Return-oriented programming (ROP) is an attack that has been shown to be able to circumvent W ^X protection. However, it was not clear if ROP can be made as powerful as non-ROP malicious code in other aspects, e.g., be packed to make static analysis difficult, be print- able to evade non-ASCII filtering, be polymorphic to evade signature-based detection, etc. Research

Kangjie Lu; Dabi Zou; Weiping Wen; Debin GAO

2011-01-01

231

The Centre for Power Transmission  

E-print Network

systems, whether for aircraft control, robotic manipulation or other multi-axis applications that limit the leakage of fluid. Friction forces are usually overcome by the hydraulic actuation capability Bois) PTO #12;5. Modelling and Development of Low Noise Hydraulic Fluid Power Systems Hydraulic fluid

Burton, Geoffrey R.

232

Experiments on Random Packings of Ellipsoids  

NASA Astrophysics Data System (ADS)

Recent simulations indicate that ellipsoids can pack randomly more densely than spheres and, remarkably, for axes ratios near 1.25?1?0.8 can approach the densest crystal packing (fcc) of spheres, with a packing fraction of 74%. We demonstrate that such dense packings are realizable. We introduce a novel way of determining packing density for a finite sample that minimizes surface effects. We have fabricated ellipsoids and show that, in a sphere, the radial packing fraction ?(r) can be obtained from V(h), the volume of added fluid to fill the sphere to height h. We also obtain ?(r) from a magnetic resonance imaging scan. The measurements of the overall density ?avr, ?(r) and the core density ?0=0.74±0.005 agree with simulations.

Man, Weining; Donev, Aleksandar; Stillinger, Frank H.; Sullivan, Matthew T.; Russel, William B.; Heeger, David; Inati, Souheil; Torquato, Salvatore; Chaikin, P. M.

2005-05-01

233

A 6-DOF vibration isolation system for hydraulic hybrid vehicles  

NASA Astrophysics Data System (ADS)

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 the regenerative system.

Nguyen, The; Elahinia, Mohammad; Olson, Walter W.; Fontaine, Paul

2006-03-01

234

Hydraulic and Habitat Suitability Analyses Technical Memorandum  

E-print Network

Appendix D Hydraulic and Habitat Suitability Analyses Technical Memorandum #12;COPYRIGHT DECEMBER Series 2 and Pond Series 3 Hydraulic and Habitat Suitability Analyses Prepared for Bureau of Reclamation HILL, INC. III Hydraulic and Habitat Suitability Analyses

235

14 CFR 25.1435 - Hydraulic systems.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Hydraulic systems. 25.1435 Section 25...Miscellaneous Equipment § 25.1435 Hydraulic systems. (a) Element design. Each element of the hydraulic system must be designed...

2010-01-01

236

Close-packing of growing discs  

SciTech Connect

Spiral lattices are derived by allowing growing discs to aggregate under a close-packing rule. Both Fibonacci and Lucas numbers of visible spirals arise naturally, dependent only on the choice of growth centre. Both the rate of convergence towards an ideal spiral, and chirality, are determined by the initial placement of the first few discs (initial conditions). Thus the appearance of spiral packings is no more or less mysterious than the appearance of hexagonal packed arrays of equal discs.

Bursill, L.A.; Xudong, F. (Melbourne Univ., Parkville (Australia). School of Physics)

1988-12-01

237

Close-Packing of Growing Discs  

NASA Astrophysics Data System (ADS)

Spiral lattices are derived by allowing growing discs to aggregate under a close-packing rule. Both Fibonacci and Lucas numbers of visible spirals arise naturally, dependent only on the choice of growth centre. Both the rate of convergence towards an ideal spiral, and chirality, are determined by the initial placement of the first few discs (initial conditions). Thus the appearance of spiral packings is no more or less mysterious than the appearance of hexagonal packed arrays of equal discs.

Bursill, L. A.; Xudong, Fan

238

Theory of cylindrical dense packings of disks.  

PubMed

We have previously explored cylindrical packings of disks and their relation to sphere packings. Here we extend the analytical treatment of disk packings, analyzing the rules for phyllotactic indices of related structures and the variation of the density for line-slip structures, close to the symmetric ones. We show that rhombic structures, which are of a lower density, are always unstable, i.e., can be increased in density by small perturbations. PMID:24827251

Mughal, A; Weaire, D

2014-04-01

239

Hydraulic wellbore erosion while drilling  

Microsoft Academic Search

This article is the first to identify nozzle hydraulic effects in a field evaluation of hole erosion. Common practice normally identifies annular velocity as the culprit for excessive hole washout. But field tests in this article clearly identify excessive nozzle hydraulics as the cause for hole erosion. Both oil-based and water-based drilling fluids were used during the field test. The

B. Chemerinski; L. Robinson

1996-01-01

240

Hydraulics of open channel flow  

Microsoft Academic Search

``Hydraulics of Open Channel Flow'' provides a complete understanding of open channel flow phenomena, and clearly explains the methods for solving the theoretical equations that represent these phenomena. Researchers and practicing engineers in charge of design of hydraulics structures, generation of hydropower, and computation of pollutant diffusion in channels and lakes will find in this essential reference a wealth of

Sergio Montes

1998-01-01

241

Tractor Hydraulics. A Teaching Reference.  

ERIC Educational Resources Information Center

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)…

American Association for Vocational Instructional Materials, Athens, GA.

242

Iterative packing for demand matching and sparse packing.  

SciTech Connect

The main result we will present is a 2k-approximation algorithm for the following 'k-hypergraph demand matching' problem: given a set system with sets of size <=k, where sets have profits & demands and vertices have capacities, find a max-profit subsystem whose demands do not exceed the capacities. The main tool is an iterative way to explicitly build a decomposition of the fractional optimum as 2k times a convex combination of integral solutions. If time permits we'll also show how the approach can be extended to a 3-approximation for 2-column sparse packing. The second result is tight w.r.t the integrality gap, and the first is near-tight as a gap lower bound of 2(k-1+1/k) is known.

Parekh, Ojas

2010-11-01

243

Hydraulically actuated well shifting tool  

SciTech Connect

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.

Roth, B.A.

1992-10-20

244

Monument Creek hydraulics project  

NSDL National Science Digital Library

Students are given some general questions (file "IntroQuestions_07.pdf") related to project design during the class session before the main project is handed out. They need to use their textbook and/or other class resources to attempt to answer these questions and to prepare to discuss them the next class session. These questions concern field reconstruction of flood hydraulics, specifically. of bankfull flow. At this next class session we discuss their answers to the preliminary questions. Students are then given the main project handout (Monument_Ck_Problem_07.pdf). This gives them the general questions to be answered in the project. After reading it, students brainstorm again as a class about how to go about answering the questions. Students then divide themselves into research of three. These teams will synthesize data together and ultimately write up the project together. Each team then sends one member to join members of other teams to do one of the three main aspects of the field or computer work (1) field identification of the bankfull channel and measurement of bankfull channel geometry, (2) field determination of modern channel roughness from modern stream hydraulics (Manning's n is back-calculated from present channel geometry and flow), (3) development of a flood-frequency curve for this reach of Monument Creek from USGS discharge data. These working groups (with one member from each research team) work initially independently in the field and subsequently doing calculations in the lab, or on the computer. Once each working group has completed what it can do on its own, these groups split up and each member of each group carries the groups results back to his/her research team, and explains to the other members of the research team what he/she has done to this point and what results he/she has for the team. The team then works to synthesize he results into an overall answer to the questions posed at the beginning of the lab (confusing enough for you?). Each research team then writes up the results, sometimes (as in 2007) as a lab write up, in other years in scientific paper format. Whether the project is turned in simply as a lab write up or as a scientific paper, students are always asked to assess sources of error and how they might affect the results. Key words: Fluvial geomorphology, fluvial hydraulics, bankfull discharge, flood-frequency analysis Designed for a geomorphology course

Leonard, Eric

245

Microbial community analysis in biocathode microbial fuel cells packed with different materials  

PubMed Central

Biocathode MFCs using microorganisms as catalysts have important advantages in lowering cost and improving sustainability. Electrode materials and microbial synergy determines biocathode MFCs performance. In this study, four materials, granular activated carbon (GAC), granular semicoke (GS), granular graphite (GG) and carbon felt cube (CFC) were used as packed cathodic materials. The microbial composition on each material and its correlation with the electricity generation performance of MFCs were investigated. Results showed that different biocathode materials had an important effect on the type of microbial species in biocathode MFCs. The microbes belonging to Bacteroidetes and Proteobacteria were the dominant phyla in the four materials packed biocathode MFCs. Comamonas of Betaproteobacteria might play significant roles in electron transfer process of GAC, GS and CFC packed biocathode MFCs, while in GG packed MFC Acidovorax may be correlated with power generation. The biocathode materials also had influence on the microbial diversity and evenness, but the differences in them were not positively related to the power production. PMID:22458430

2012-01-01

246

Microbial community analysis in biocathode microbial fuel cells packed with different materials.  

PubMed

Biocathode MFCs using microorganisms as catalysts have important advantages in lowering cost and improving sustainability. Electrode materials and microbial synergy determines biocathode MFCs performance. In this study, four materials, granular activated carbon (GAC), granular semicoke (GS), granular graphite (GG) and carbon felt cube (CFC) were used as packed cathodic materials. The microbial composition on each material and its correlation with the electricity generation performance of MFCs were investigated. Results showed that different biocathode materials had an important effect on the type of microbial species in biocathode MFCs. The microbes belonging to Bacteroidetes and Proteobacteria were the dominant phyla in the four materials packed biocathode MFCs. Comamonas of Betaproteobacteria might play significant roles in electron transfer process of GAC, GS and CFC packed biocathode MFCs, while in GG packed MFC Acidovorax may be correlated with power generation. The biocathode materials also had influence on the microbial diversity and evenness, but the differences in them were not positively related to the power production. PMID:22458430

Sun, Yanmei; Wei, Jincheng; Liang, Peng; Huang, Xia

2012-01-01

247

Some Fundamental Mechanisms of Hydraulic Fracturing.  

E-print Network

??This dissertation focuses mainly on three topics: (1) mixed-mode branching and segmentation of hydraulic fractures in brittle materials, (2) hydraulic fracture propagation in particulate materials,… (more)

Wu, Ruiting

2006-01-01

248

Hydraulic system for a ratio change transmission  

DOEpatents

Disclosed is a drive assembly (10) for an electrically powered vehicle (12). The assembly includes a transaxle (16) having a two-speed transmission (40) and a drive axle differential (46) disposed in a unitary housing assembly (38), an oil-cooled prime mover or electric motor (14) for driving the transmission input shaft (42), an adapter assembly (24) for supporting the prime mover on the transaxle housing assembly, and a hydraulic system (172) providing pressurized oil flow for cooling and lubricating the electric motor and transaxle and for operating a clutch (84) and a brake (86) in the transmission to shift between the two-speed ratios of the transmission. The adapter assembly allows the prime mover to be supported in several positions on the transaxle housing. The brake is spring-applied and locks the transmission in its low-speed ratio should the hydraulic system fail. The hydraulic system pump is driven by an electric motor (212) independent of the prime mover and transaxle.

Kalns, Ilmars (Northville, MI)

1981-01-01

249

Marginal stability in jammed packings: quasicontacts and weak contacts.  

PubMed

Maximally random jammed (MRJ) sphere packing is a prototypical example of a system naturally poised at the margin between underconstraint and overconstraint. This marginal stability has traditionally been understood in terms of isostaticity, the equality of the number of mechanical contacts and the number of degrees of freedom. Quasicontacts, pairs of spheres on the verge of coming in contact, are irrelevant for static stability, but they come into play when considering dynamic stability, as does the distribution of contact forces. We show that the effects of marginal dynamic stability, as manifested in the distributions of quasicontacts and weak contacts, are consequential and nontrivial. We study these ideas first in the context of MRJ packing of d-dimensional spheres, where we show that the abundance of quasicontacts grows at a faster rate than that of contacts. We reexamine a calculation of Jin et al. [Phys. Rev. E 82, 051126 (2010)], where quasicontacts were originally neglected, and we explore the effect of their inclusion in the calculation. This analysis yields an estimate of the asymptotic behavior of the packing density in high dimensions. We argue that this estimate should be reinterpreted as a lower bound. The latter part of the paper is devoted to Bravais lattice packings that possess the minimum number of contacts to maintain mechanical stability. We show that quasicontacts play an even more important role in these packings. We also show that jammed lattices are a useful setting for studying the Edwards ensemble, which weights each mechanically stable configuration equally and does not account for dynamics. This ansatz fails to predict the power-law distribution of near-zero contact forces, P(f)?f(?). PMID:25215696

Kallus, Yoav; Torquato, Salvatore

2014-08-01

250

Battery pack/controller for high temperature applications  

SciTech Connect

At temperatures in excess of 300/sup 0/C, standard conductive wirelines cannot be used for signal or power transmission in geothermal wells. At such temperatures, a mechanical slickline can be used to raise and lower instrumentation, but the instrumentation control and power must then be self contained. This paper reviews the development of a battery and timing circuit to control a motor in a Los Alamos National Laboratory sampling tool. The battery pack-controller circuitry enclosed in a dewar was used in the Salton Sea Scientific Drilling Project (SSSDP) for temperatures approaching 400/sup 0/C.

Wolfenbarger, F.M.

1986-01-01

251

Hydraulic line pressure control system for an infinitely variable transmission  

SciTech Connect

An improved control system is described for an infinitely variable transmission for transmitting the power of an internal combustion engine mounted on a vehicle. The transmission comprises: a primary pulley having a hydraulically shiftable disc and a hydraulic cylinder for shifting the disc, a secondary pulley having a hydraulically shiftable disc and a hydraulic cylinder for operating the disc, a belt engaged with both pulleys, and a hydraulic circuit having a pump for supplying oil. It also comprises: a transmission ratio control valve responsive to engine speed for controlling the oil and for shifting the disc of the primary pulley to change the transmission ratio, and a pressure regulator valve responsive to the transmission ratio for increasing the line pressure of the hydraulic circuit with increase of the transmission ratio. The improvement described here comprises: first means comprising a throttle position sensor for detecting the torque of the engine and an electronic circuit responsive to an output signal of the throttle position sensor for producing a control signal proportional to the torque; and second means responsive to the control signal for operating the pressure regulator valve so as to increase the line pressure with increase of the torque.

Sakai, Y.

1987-01-27

252

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT X, AUTOMATIC TRANSMISSIONS--HYDRAULIC SYSTEMS (PART II).  

ERIC Educational Resources Information Center

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…

Human Engineering Inst., Cleveland, OH.

253

Integrated modeling of an electro-hydraulic servo manipulator using linear graphs  

Microsoft Academic Search

Analysis and design of mechatronic systems require integrated and concurrent tools. This paper presents an integrated mechatronic modeling tool using linear graphs (LG) theory. To demonstrate the capabilities of the presented framework, an integrated model of a complex electro-hydraulic servo manipulator and its governing motion equations in the state space form are presented. It includes a hydraulic power supply unit,

M. Ganji; S. Behbahani; C. W. de Silva

2010-01-01

254

Numerical prediction of erosion on guide vanes and in labyrinth seals in hydraulic turbines  

Microsoft Academic Search

Erosion in hydraulic power plants is caused by sand particles in the flow. This is one of the major problems that restricts the lifetime between overhauls of water turbines. Especially those parts of the hydraulic turbine which are exposed to high flow velocities bear a considerable risk of being damaged by erosion processes. Therefore, suitable methods for the prediction of

Reiner Mack; Peter Drtina; Egon Lang

1999-01-01

255

Multiple Destination Bin Packing Bram Verweij  

E-print Network

about on-line and off-line algorithms to solve the two and three dimensional bin packing problem be calculated using dynamic programming in exponential time relative to the size of the input, or by applying applications of the bin packing problem involve two and three dimensional problems, such as loading pallets

Utrecht, Universiteit

256

Circle Packing Explorations Francesco De Comite  

E-print Network

Circle Packing Explorations Francesco De Comit´e Laboratoire d'Informatique Fondamentale de Lille University of Sciences and Technology of Lille France Francesco.De-Comite@univ-lille1.fr Abstract Circle packing can be seen as the art of placing tangent circles on the plane, leaving as little unoccupied space

Paris-Sud XI, Université de

257

CIRCLE PACKING BIBLIOGRAPHY AS OF SEPTEMBER 2005  

E-print Network

CIRCLE PACKING BIBLIOGRAPHY AS OF SEPTEMBER 2005 MAINTAINED BY KENNETH STEPHENSON The term circle packing here refers to configurations of circles with specified pat- terns of tangency, intersection", which is concerned with density and coverings using spheres of given radii.) The software package Circle

Stephenson, Kenneth

258

Is Incest Common In Gray Wolf Packs?  

NSDL National Science Digital Library

In early 2000 the Northern Prairie Wildlife Research Center posted this resource on wolves at their Website. "Is Incest Common In Gray Wolf Packs?" suggests that incest is rare in wolf packs. The resource may be downloaded as a .zip file.

Adams, Layne G.; Burch, John W.; Geffen, Eli ..; Mech, L. D.; Meier, Thomas J.; Smith, Deborah.

259

Compact attic mounted solar heating pack assembly  

Microsoft Academic Search

A compact attic solar heating pack assembly for mounting within a building attic having south and north facing roof sections overlying a horizontal building attic floor forming the ceiling and defining an enclosed attic space above the occupied room space below the ceiling is described. The pack assembly comprises: a closed sheet metal plenum, means for fixedly mounting the plenum

1988-01-01

260

Kid's PACK: Population Awareness Campaign Kit.  

ERIC Educational Resources Information Center

This fun and educational kit is designed specifically for elementary students. The "Kid's PACK" (Population Awareness Campaign Kit) entertains and informs children on the environment and human population growth through stories, games, and concrete ideas for making a difference. In three booklets, the "Kid's PACK" offers elementary students…

Zero Population Growth, Inc., Washington, DC.

261

Softening of Granular Packings with Dynamic Forcing  

E-print Network

We perform numerical simulations of a two-dimensional bidisperse granular packing subjected to both a static confining pressure and a sinusoidal dynamic forcing applied by a wall on one edge of the packing. We measure the response experienced by a wall on the opposite edge of the packing and obtain the resonant frequency of the packing as the static or dynamic pressures are varied. Under increasing static pressure, the resonant frequency increases, indicating a velocity increase of elastic waves propagating through the packing. In contrast, when the dynamic amplitude is increased for fixed static pressure, the resonant frequency decreases, indicating a decrease in the wave velocity. This occurs both for compressional and for shear dynamic forcing, and is in agreement with experimental results. We find that the average contact number $Z_c$ at the resonant frequency decreases with increasing dynamic amplitude, indicating that the elastic softening of the packing is associated with a reduced number of grain-grain contacts through which the elastic waves can travel. We image the excitations created in the packing and show that there are localized disturbances or soft spots that become more prevalent with increasing dynamic amplitude. Our results are in agreement with experiments on glass bead packings and earth materials such as sandstone and granite, and may be relevant to the decrease in elastic wave velocities that has been observed to occur near fault zones after strong earthquakes, in surficial sediments during strong ground motion, and in structures during earthquake excitation.

C. J. Olson Reichhardt; L. M. Lopatina; X. Jia; P. A. Johnson

2014-06-17

262

Enhanced EP halftones with hexagonal dot packing  

E-print Network

Enhanced EP halftones with hexagonal dot packing Tomasz J. Cholewo, Steve Weed, Brian Cooper advantages for electropho- tographic (EP) printing over conventional dot placement on a square grid [1] reported that hexagonal dot packing could have some unique benefits for EP printing. These were

Cholewo, Tomasz

263

7 CFR 51.1527 - Standard pack.  

Code of Federal Regulations, 2012 CFR

...container. (4) “Tightly packed” means the plums or prunes are the proper size for the mold or cell compartments in which they are packed, and the molds or cells are filled in such a way that movement is not allowed. (b) Marking....

2012-01-01

264

7 CFR 51.1527 - Standard pack.  

Code of Federal Regulations, 2011 CFR

...container. (4) “Tightly packed” means the plums or prunes are the proper size for the mold or cell compartments in which they are packed, and the molds or cells are filled in such a way that movement is not allowed. (b) Marking....

2011-01-01

265

7 CFR 51.1527 - Standard pack.  

Code of Federal Regulations, 2010 CFR

...container. (4) “Tightly packed” means the plums or prunes are the proper size for the mold or cell compartments in which they are packed, and the molds or cells are filled in such a way that movement is not allowed. (b) Marking....

2010-01-01

266

7 CFR 51.1527 - Standard pack.  

Code of Federal Regulations, 2014 CFR

...container. (4) “Tightly packed” means the plums or prunes are the proper size for the mold or cell compartments in which they are packed, and the molds or cells are filled in such a way that movement is not allowed. (b) Marking....

2014-01-01

267

7 CFR 51.1527 - Standard pack.  

Code of Federal Regulations, 2013 CFR

...container. (4) “Tightly packed” means the plums or prunes are the proper size for the mold or cell compartments in which they are packed, and the molds or cells are filled in such a way that movement is not allowed. (b) Marking....

2013-01-01

268

Pack rats (Neotoma spp.): Keystone ecological engineers?  

Technology Transfer Automated Retrieval System (TEKTRAN)

The potential role of two species of pack rats (Neotoma albigula and Neotoma micropus) as keystone ecological engineers was examined by estimating the species diversity of invertebrates living in the nest middens, and nitrogen mineralization rates in soils associated with the middens. Although pack-...

269

Mud pack therapy in rheumatoid arthritis  

Microsoft Academic Search

Summary Twenty-eight patients with classical or definite rheumatoid arthritis were randomly divided into two groups of fourteen patients each. All patients were treated once a day with mud packs derived from the Dead Sea heated to 40°C and applied over the four extremities, neck and back for 20 minutes. Group 1 was treated with the true mud packs and Group

S. Sukenik; D. Buskila; L. Neumann; A. Kleiner-Baumgarten

1992-01-01

270

Rectangle-packing-based module placement  

Microsoft Academic Search

The first and the most critical stage in VLSI layout design is the placement, the background of which is the rectangle packing problem: Given many rectangular modules of arbitrary size, place them without overlapping on a layer in the smallest bounding rectangle. Since the variety of the packing is infinite (two- dimensionally continuous) many, the key issue for successful optimization

Hiroshi Murata; Kunihiro Fujiyoshi; Shigetoshi Nakatake; Yoji Kajitani

1995-01-01

271

Calculator programs determine drilling hydraulics  

SciTech Connect

This paper describes Hydraulics II, which is prepared for the calculation of bit hydraulics and pump performance on the TI-59 using a PC-100C printer. The operator is prompted for the required input data with a printed register number and an abbreviated title. Output is printed and labeled. As in Hydraulics I, three magnetic cards are required, two for the program and the third for the alphanumeric memory of the prompts and output labels. Lines 000 through 100 are the same in both of these programs. The alphanumerics are stored in registers 31 through 53. The machine is partitioned 479.59.

Landry, W.E.

1987-06-01

272

Electrokinetic high pressure hydraulic system  

DOEpatents

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.

Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA)

2000-01-01

273

Coalescence preference in densely packed microbubbles.  

PubMed

A bubble merged from two parent bubbles with different size tends to be placed closer to the larger parent. This phenomenon is known as the coalescence preference. Here we demonstrate that the coalescence preference can be blocked inside a densely packed cluster of bubbles. We utilized high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence events inside densely packed microbubbles with a local packing fraction of ~40%. The surface energy release theory predicts an exponent of 5 in a relation between the relative coalescence position and the parent size ratio, whereas our observation for coalescence in densely packed microbubbles shows a different exponent of 2. We believe that this result would be important to understand the reality of coalescence dynamics in a variety of packing situations of soft matter. PMID:25583640

Kim, Yeseul; Lim, Su Jin; Gim, Bopil; Weon, Byung Mook

2015-01-01

274

Coalescence preference in densely packed microbubbles  

PubMed Central

A bubble merged from two parent bubbles with different size tends to be placed closer to the larger parent. This phenomenon is known as the coalescence preference. Here we demonstrate that the coalescence preference can be blocked inside a densely packed cluster of bubbles. We utilized high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence events inside densely packed microbubbles with a local packing fraction of ~40%. The surface energy release theory predicts an exponent of 5 in a relation between the relative coalescence position and the parent size ratio, whereas our observation for coalescence in densely packed microbubbles shows a different exponent of 2. We believe that this result would be important to understand the reality of coalescence dynamics in a variety of packing situations of soft matter. PMID:25583640

Kim, Yeseul; Lim, Su Jin; Gim, Bopil; Weon, Byung Mook

2015-01-01

275

Powered Remote Manipulators Perform Hazardous Retrieval, Handling, and Size Reduction Operations  

SciTech Connect

This paper describes a new lightweight, powered remote manipulator (PRM) that S.A.Robotics has developed for remote material handling and size reduction in hazardous environments such as reactor decommissioning projects. PRMs can be mounted to various deployment platforms such as remote controlled track-driven vehicles, commercial All Terrain Vehicles, or crane-mounted arms. They can also be installed as replacements for traditional Master-Slave Manipulators (MSMs) in hot cells. The PRM is a six degree of freedom manipulator with carbon fiber structural components that can provide up to a 3 meter (10 foot) reach. Either electric or hydraulic power options can be used and a variety of hydraulic fluids are available to meet combustible material limitations. The PRM is operated with easy-to-use joystick controls that allow operators to sit in a comfortable work station and handle 90 kg (200 pound) loads with a hydraulic power pack or 45 kg (100 pounds) with electric servo-motor driven equipment. With a quick disconnect tool changer, the manipulator can operate grippers, drills, shears, saws, sampling and survey instruments, and the arm can also deploy cameras and lights to support a wide range of remote applications. (authors)

Cole, M.D.; Owen, J.R.; Adams, S.R. [S.A.Robotics, Inc., 3985 S. Lincoln Avenue, Suite 100, Loveland, Colorado 80241 (United States)

2006-07-01

276

Packed Bed Reactor Experiment - Duration: 0:17.  

NASA Video Gallery

The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

277

Hydraulic Loaders in Forestry Operations  

Microsoft Academic Search

I Historical background:Development from horse-skidding, wire cranes to hydraulic loaders.II Application of hydraulic loaders In forestry:Description of the different existing forestry applications and characterisations of different types of loaders.III Forestry loaders versus materials handling cranes:Differences in design and use.IV What are the requirements for a timber loader?Importance of reach, capacity strength, weight, geometry, flexibility and safety aspects.V Prerequisites for producing

Peter B. L. Lindgren

1977-01-01

278

View south of hydraulic hammer in boilermakers shop (probably the ...  

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

View south of hydraulic hammer in boilermakers shop (probably the oldest piece of equipment in the yard, originally powered by steam) nameplate: United Engineers and FDRY. Co. Pittsburgh, Pa, USA Davy Brothers LTD. Patents - Aug 1, 1905, Feb, 1901, Sept 8, 1908 - 10000 lbs. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Structure Shop, League Island, Philadelphia, Philadelphia County, PA

279

Model-based remote handling with the MAESTRO hydraulic manipulator  

Microsoft Academic Search

A powerful hydraulic manipulator may be a useful tool to deal efficiently with the remote handling, dexterous operations required during the Divertor maintenance. Its main advantages are a good weight capacity, the large range of tasks that can be addressed and its capability to recover from unforeseen situations. On the other hand, it implies intensive video monitoring and the use

Philippe Gravez; C. Leroux; M. Irving; L. Galbiati; A. Raneda; M. Siuko; D. Maisonnier; J. D. Palmer

2003-01-01

280

Analysis of Small-Scale Hydraulic Actuation Jicheng Xia  

E-print Network

of force and power while at the same time being relatively light weight compared to the equivalent to an equivalent electromechanical system comprised of off-the-shelf components. Calculation results revealed that high operating pressures are needed for small-scale hydraulics to be lighter than the equivalent

Durfee, William K.

281

Indirect Adaptive Robust Control of Electro-Hydraulic Systems Driven by Single-Rod Hydraulic Actuator  

E-print Network

Indirect Adaptive Robust Control of Electro-Hydraulic Systems Driven by Single-Rod Hydraulic) of electro-hydraulic systems driven by single- rod hydraulic actuators. Unlike the tracking that the proposed IARC achieves good tracking performance and accurate parameter estimation. INTRODUCTION Electro-hydraulic

Yao, Bin

282

Monitoring Three-Dimensional Packings in Microgravity  

E-print Network

We present results from experiments with granular packings in three dimensions in microgravity as realized on parabolic flights. Two different techniques are employed to monitor the inside of the packings during compaction: (1) X-ray radiography is used to measure in transmission the integrated fluctuations of particle positions. (2) Stress-birefringence in three dimensions is applied to visualize the stresses inside the packing. The particle motions below the transition into an arrested packing are found to produce a well agitated state. At the transition, the particles lose their energy quite rapidly and form a stress network. With both methods, non-arrested particles (rattlers) can be identified. In particular, it is found that rattlers inside the arrested packing can be excited to appreciable dynamics by the rest-accelerations (g-jitter) during a parabolic flight without destroying the packings. At low rates of compaction, a regime of slow granular cooling is identified. The slow cooling extends over several seconds, is described well by a linear law, and terminates in a rapid final collapse of dynamics before complete arrest of the packing.

Peidong Yu; Stefan Frank-Richter; Alexander Borngen; Matthias Sperl

2013-12-21

283

A Hermite cubic collocation scheme for plane strain hydraulic fractures Department of Mathematics, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z2  

E-print Network

A Hermite cubic collocation scheme for plane strain hydraulic fractures A. Peirce Department Accepted 13 February 2010 Available online 4 March 2010 Keywords: Hydraulic fractures Integro the propagation of a hydraulic fracture in a state of plane strain. Special blended cubic Hermite-power­law basis

Peirce, Anthony

284

A Hermite cubic collocation scheme for plane strain hydraulic fractures Department of Mathematics, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z2  

E-print Network

A Hermite cubic collocation scheme for plane strain hydraulic fractures A. Peirce Department Accepted 13 February 2010 Available online xxxx Keywords: Hydraulic fractures Integro-partial differential of a hydraulic fracture in a state of plane strain. Special blended cubic Hermite-power­law basis functions

Peirce, Anthony

285

Hydraulic tests of emergency cooling system: L-Area  

SciTech Connect

The delay in L-Area startup provided an opportunity to obtain valuable data on the Emergency Cooling System (ECS) which will permit reactor operation at the highest safe power level. ECS flow is a major input to the FLOOD code which calculates reactor ECS power limits. The FLOOD code assesses the effectiveness of the ECS cooling capacity by modeling the core and plenum hydraulics under accident conditions. Presently, reactor power is not limited by the ECS cooling capacity (power limit). However, the manual calculations of ECS flows had been recently updated to include piping changes (debris strainer, valve changes, pressure release systems) and update fitting losses. Both updates resulted in reduced calculated ECS flows. Upon completion of the current program to update, validate, and document, reactor power may be limited under certain situations by ECS cooling capacity for some present reactor charge designs. A series of special hydraulic tests (Reference 1, 3) were conducted in L-Area using all sources of emergency coolant including the ECS pumps (Reference 2). The tests provided empirical hydraulic data on the ECS piping. These data will be used in computer models of the system as well as manual calculations of ECS flows. The improved modeling and accuracy of the flow calculations will permit reactor operation at the highest safe power level with respect to an ECS power limit.

Hinton, J H

1988-01-01

286

Modular Approach for Continuous Cell-Level Balancing to Improve Performance of Large Battery Packs: Preprint  

SciTech Connect

Energy storage systems require battery cell balancing circuits to avoid divergence of cell state of charge (SOC). A modular approach based on distributed continuous cell-level control is presented that extends the balancing function to higher level pack performance objectives such as improving power capability and increasing pack lifetime. This is achieved by adding DC-DC converters in parallel with cells and using state estimation and control to autonomously bias individual cell SOC and SOC range, forcing healthier cells to be cycled deeper than weaker cells. The result is a pack with improved degradation characteristics and extended lifetime. The modular architecture and control concepts are developed and hardware results are demonstrated for a 91.2-Wh battery pack consisting of four series Li-ion battery cells and four dual active bridge (DAB) bypass DC-DC converters.

Muneed ur Rehman, M.; Evzelman, M.; Hathaway, K.; Zane, R.; Plett, G. L.; Smith, K.; Wood, E.; Maksimovic, D.

2014-10-01

287

Tomographic analysis of jammed ellipsoid packings  

NASA Astrophysics Data System (ADS)

Disordered packings of ellipsoidal particles are an important model for disordered granular matter. Here we report a way to determine the average contact number of ellipsoid packings from tomographic analysis. Tomographic images of jammed ellipsoid packings prepared by vertical shaking of loose configurations are recorded and the positions and orientations of the ellipsoids are reconstructed. The average contact number can be extracted from a contact number scaling (CNS) function. The size of the particles, that may vary due to production inaccuracies, can also be determined by this method.

Schaller, Fabian M.; Neudecker, Max; Saadatfar, Mohammad; Delaney, Gary; Mecke, Klaus; Schröder-Turk, Gerd E.; Schröter, Matthias

2013-06-01

288

DEM simulation of experimental dense granular packing  

SciTech Connect

In this study we present numerical analysis performed on the experimental results of sphere packings of mono-sized hard sphere whose packing fraction spans across a wide range of 0.59<{Phi}<0.72. Using X-ray Computed Tomography (XCT), we have full access to the 3D structure of the granular packings. Numerical analysis performed on thr data provides the first experimental proofs of how densification affects local order parameters. Furthermore by combining Discrete Element Method (DEM) and the experimental results from XCT, we investigate how the intergranular forces change with the onset of crystallization.

Hanifpour, Maryam; Allaei, Mehdi Vaez [Department of Physics, University of Tehran, Tehran (Iran, Islamic Republic of); Francois, Nicolas; Saadatfar, Mohammad [Department of Applied Mathematics, Research School of Physics and Engineering, Australian National University, Canberra (Australia)

2013-06-18

289

Structural properties of dense hard sphere packings.  

PubMed

We numerically study structural properties of mechanically stable packings of hard spheres (HS), in a wide range of packing fractions 0.53 ? ? ? 0.72. Detailed structural information is obtained from the analysis of orientational order parameters, which clearly reveals a disorder-order phase transition at the random close packing (RCP) density, ?c ? 0.64. Above ?c, the crystalline nuclei form 3D-like clusters, which upon further desification transform into alternating planar-like layers. We also find that particles with icosahedral symmetry survive only in a narrow density range in the vicinity of the RCP transition. PMID:25098389

Klumov, Boris A; Jin, Yuliang; Makse, Hernán A

2014-09-11

290

Self-organized packs selection in predator-prey ecosystems.  

PubMed

We present a lattice model of a system of predators of five kinds, competing for prey. The predators are grouped in packs and characterized by two parameters-the energy spent on hunting and energy gained by the kill. The success of hunting depends on the actual competition among predators found near a prey. We determine via Monte Carlo simulations the numbers of predators of each kind as a function of time and the distribution of the size of their packs. We show that the ratio of the energy spent by the competing predators determines their fate. The energy gain plays only a secondary role. We show also that the system self-organizes itself into groups of predators living in well defined packs, which size depends on the energy spent. The most preferred size dependence on the energy spent follows a very simple power law. We present also a mean-field-type approach to the problem and we discuss the differences in the results obtained by the two methods, showing in particular, that the simulation approach produces more reliable results. PMID:16605368

Pekalski, Andrzej; Droz, Michel

2006-02-01

291

THE THREE DIMENSIONAL THERMAL HYDRAULIC CODE BAGIRA.  

SciTech Connect

BAGIRA - a thermal-hydraulic program complex was primarily developed for using it in nuclear power plant simulator models, but is also used as a best-estimate analytical tool for modeling two-phase mixture flows. The code models allow consideration of phase transients and the treatment of the hydrodynamic behavior of boiling and pressurized water reactor circuits. It provides the capability to explicitly model three-dimensional flow regimes in various regions of the primary and secondary circuits such as, the mixing regions, circular downcomer, pressurizer, reactor core, main primary loops, the steam generators, the separator-reheaters. In addition, it is coupled to a severe-accident module allowing the analysis of core degradation and fuel damage behavior. Section II will present the theoretical basis for development and selected results are presented in Section III. The primary use for the code complex is to realistically model reactor core behavior in power plant simulators providing enhanced training tools for plant operators.

KALINICHENKO,S.D.; KOHUT,P.; KROSHILIN,A.E.; KROSHILIN,V.E.; SMIRNOV,A.V.

2003-05-04

292

Control apparatus for hydraulically driven generator  

SciTech Connect

Apparatus for controlling a hydraulically driven generator for supplying electrical power to power mains. The generator is coupled to a turbine driven by a fluid flow through a duct. The duct has a one-fourth turn butterfly valve controlled by a fluid-actuated operator and the operator receives fluid from the duct by way of a normally closed valve which, when energized, creates water pressure on the operator for opening the butterfly valve. A second, normally open solenoid provides an emergency exit for the water from the operator to relieve the water pressure thereon and thereby close the butterfly valve when certain conditions exist, such as sudden loss of line voltage, overvoltage or deviation in frequency of the line voltage. A differential pressure switch across the turbine rotor also controls the starting of the system to assure proper flow of fluid through the duct before commencing operation of the generator itself.

Beckwith, S.

1985-08-06

293

Groundwater well with reactive filter pack  

DOEpatents

A method and apparatus for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques.

Gilmore, Tyler J. (Pasco, WA); Holdren, Jr., George R. (Kennewick, WA); Kaplan, Daniel I. (Richland, WA)

1998-01-01

294

Consequence of Body Packing of Illicit Drugs  

Microsoft Academic Search

Background: During the last decade, increased rates of drug traffic have led the smugglers to use various methods. One of these methods of illicit drug smuggling is body packing. Smuggling by intra-abdominal concealment is called \\

Hossein Hassanian-Moghaddam

295

Extension of Pack Method for Compressive Tests  

NASA Technical Reports Server (NTRS)

The pack method for determining compressive stress-strain graphs described in NACA Report No. 649 has been modified to extend it's application to thinner gages and stronger materials. The principal modifications consisted in the provision of additional support against instability cementing the specimens of the pack together with fused shellac and the provision of special clamps to hold the specimens together while the test is in progress. The shellac was found to increase the buckling load of the pack without any appreciable effect on the compressive stress-strain graph of the material. The extended pack method described in this note has made possible the application of stresses in excess of 220 kips per square inch to sheet material having a thickness of only 0.02 inch.

Aitchison, C S

1940-01-01

296

Finite Element Simulation of Dense Wire Packings  

E-print Network

A finite element program is presented to simulate the process of packing and coiling elastic wires in two- and three-dimensional confining cavities. The wire is represented by third order beam elements and embedded into a corotational formulation to capture the geometric nonlinearity resulting from large rotations and deformations. The hyperbolic equations of motion are integrated in time using two different integration methods from the Newmark family: an implicit iterative Newton-Raphson line search solver, and an explicit predictor-corrector scheme, both with adaptive time stepping. These two approaches reveal fundamentally different suitability for the problem of strongly self-interacting bodies found in densely packed cavities. Generalizing the spherical confinement symmetry investigated in recent studies, the packing of a wire in hard ellipsoidal cavities is simulated in the frictionless elastic limit. Evidence is given that packings in oblate spheroids and scalene ellipsoids are energetically preferred to spheres.

R. Vetter; F. K. Wittel; N. Stoop; H. J. Herrmann

2011-11-22

297

Groundwater well with reactive filter pack  

DOEpatents

A method and apparatus are disclosed for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques. 3 figs.

Gilmore, T.J.; Holdren, G.R. Jr.; Kaplan, D.I.

1998-09-08

298

Mechanical Characterization of Partially Crystallized Sphere Packings  

NASA Astrophysics Data System (ADS)

We study grain-scale mechanical and geometrical features of partially crystallized packings of frictional spheres, produced experimentally by a vibrational protocol. By combining x-ray computed tomography, 3D image analysis, and discrete element method simulations, we have access to the 3D structure of internal forces. We investigate how the network of mechanical contacts and intergranular forces change when the packing structure evolves from amorphous to near perfect crystalline arrangements. We compare the behavior of the geometrical neighbors (quasicontracts) of a grain to the evolution of the mechanical contacts. The mechanical coordination number Zm is a key parameter characterizing the crystallization onset. The high fluctuation level of Zm and of the force distribution in highly crystallized packings reveals that a geometrically ordered structure still possesses a highly random mechanical backbone similar to that of amorphous packings.

Hanifpour, M.; Francois, N.; Vaez Allaei, S. M.; Senden, T.; Saadatfar, M.

2014-10-01

299

Design Packing to Safely Mail Raw Spaghetti  

NSDL National Science Digital Library

Students use their creative skills to determine a way to safely mail raw (dry, uncooked) spaghetti using only the provided materials. To test the packing designs, the spaghetti is mailed through the postal system and evaluated after delivery.

Center For Engineering Educational Outreach

300

Universal Structural Characteristics of Planar Granular Packs  

NASA Astrophysics Data System (ADS)

The dependence of structural self-organization of granular materials on preparation and grain parameters is key to predictive modeling. We study 60 different mechanically equilibrated polydisperse disc packs, generated numerically by two protocols. We show that, for same-variance disc size distributions (DSDs), (1) the mean coordination number of rattler-free packs versus the packing fraction is a function independent of initial conditions, friction, and the DSD, and (2) all quadron volume and cell order distributions collapse to universal forms, also independent of the above. This apparent universality suggests that, contrary to common wisdom, equilibrated granular structures may be determined mainly by the packing protocol and higher moments of the DSD.

Matsushima, Takashi; Blumenfeld, Raphael

2014-03-01

301

A Versatile, Automatic Chromatographic Column Packing Device  

ERIC Educational Resources Information Center

Describes an inexpensive apparatus for packing liquid and gas chromatographic columns of high efficiency. Consists of stainless steel support struts, an Automat Getriebmotor, and an associated three-pulley system capable of 10, 30, and 300 rpm. (MLH)

Barry, Eugene F.; And Others

1977-01-01

302

7 CFR 920.13 - Pack.  

Code of Federal Regulations, 2014 CFR

...FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Definitions § 920.13 Pack. ...arrangement, size, weight, count, or grade of a quantity of kiwifruit in a particular type and size of container, or any...

2014-01-01

303

7 CFR 920.13 - Pack.  

Code of Federal Regulations, 2012 CFR

...Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Definitions § 920.13 Pack. ...arrangement, size, weight, count, or grade of a quantity of kiwifruit in a particular type and size of container, or any...

2012-01-01

304

7 CFR 920.13 - Pack.  

Code of Federal Regulations, 2013 CFR

...FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Definitions § 920.13 Pack. ...arrangement, size, weight, count, or grade of a quantity of kiwifruit in a particular type and size of container, or any...

2013-01-01

305

7 CFR 920.13 - Pack.  

Code of Federal Regulations, 2011 CFR

...Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Definitions § 920.13 Pack. ...arrangement, size, weight, count, or grade of a quantity of kiwifruit in a particular type and size of container, or any...

2011-01-01

306

7 CFR 29.2541 - Packing.  

Code of Federal Regulations, 2010 CFR

...REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Kentucky and Tennessee Fire-Cured and Foreign-Grown Fire-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2541 Packing. A lot of...

2010-01-01

307

7 CFR 29.2541 - Packing.  

Code of Federal Regulations, 2011 CFR

...REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Kentucky and Tennessee Fire-Cured and Foreign-Grown Fire-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2541 Packing. A lot of...

2011-01-01

308

Why is Random Close Packing Reproducible?  

Microsoft Academic Search

We link the thermodynamics of colloidal suspensions to the statistics of\\u000aregular and random packings. Random close packing has defied a rigorous\\u000adefinition yet, in three dimensions, there is near universal agreement on the\\u000avolume fraction at which it occurs. We conjecture that the common value of\\u000aphi_rcp, approximately 0.64, arises from a divergence in the rate at which\\u000aaccessible

Randall D. Kamien; Andrea J. Liu

2007-01-01

309

Packing numbers of rational ruled 4-manifolds  

Microsoft Academic Search

We completely solve the symplectic packing problem with equally sized balls for any rational, ruled, symplectic 4-manifolds. We give explicit formulae for the packing numbers, the generalized Gromov widths, the stability numbers, and the corresponding obstructing exceptional classes. As a corollary, we give explicit values for when an ellipsoid of type $E(a, b)$, with $\\\\frac{b}{a} \\\\in \\\\N$, embeds in a

Olguta Buse; Martin Pinsonnault

2011-01-01

310

Software For Nearly Optimal Packing Of Cargo  

NASA Technical Reports Server (NTRS)

PACKMAN computer program used to find nearly optimal arrangements of cargo items in storage containers, subject to such multiple packing objectives as utilization of volumes of containers, utilization of containers up to limits on weights, and other considerations. Automatic packing algorithm employed attempts to find best positioning of cargo items in container, such that volume and weight capacity of container both utilized to maximum extent possible. Written in Common LISP.

Fennel, Theron R.; Daughtrey, Rodney S.; Schwaab, Doug G.

1994-01-01

311

[Performance evaluation of three novel biotrickling packings].  

PubMed

Packing is the support medium for microbial adhesion and water retention, and its characteristics are directly related to the removal of pollutants. In the present study, three novel biotrickling packings were developed: polyhedral sphere, burr sphere and polyhedral hollow column. The results showed that the structural characteristics of polyhedral sphere and polyhedral hollow column, with the specific surface area of 200 m2 x m(-3), were better than those of traditional biotrickling packings. The resistance coefficient zeta of polyhedral sphere was almost identical before and after the biofilm formation. Under the same condition, zeta of burr sphere increased much more. Investigations on the start-up time showed that the polyhedral hollow columns could contribute more to the quick biofilm formation. The performance of BTF which was packed with polyhedral sphere was better than the others. When the inlet concentrations of toluene and ethanol were 687.37 and 651.17 mg x m(-3), the removal efficiencies achieved 76.78% and 99.23%, respectively. Biomass measurements showed that the biomass adhering on these packings were more than that on the common polypropylene Bauer ring. Biofilm could be renewed and removed easily from the polyhedral sphere and the pressure drop could maintain at 51.6 Pa x m(-1) at the later stable running phase. However, the pressure drop in the BTF which used burr sphere as the packings increased much more (193.3 Pa x m(-1)), thus causing a clogging phenomenon. PMID:24640905

Mei, Yu; Cheng, Zhuo-Wei; Wang, Jia-De; Huo, Po

2013-12-01

312

The frequency distribution of mechanically stable packings  

NASA Astrophysics Data System (ADS)

We generate mechanically stable packings of soft particles in 2D using an algorithm in which we successively grow or shrink purely repulsive grains and minimize the total energy at each step until particles are just at contact and at rest. We focus on small systems of up to 20 particles, and thus we are able to enumerate nearly all of the possible mechanically stable packings. Complete enumeration allows us to factorize the probability distribution, P(?), for obtaining a mechanically stable state at packing fraction ? into algorithm-dependent and independent contributions, ?(?) and ?(?). ?(?) is the probability density to obtain a distinct mechanically stable packing at ?, while ?(?) is the frequency with which each distinct state occurs. We found several remarkable features of the frequency distribution. For example, the frequency averaged over bins of width d? grows exponentially with increasing packing fraction. In addition, distinct mechanically stable packings within d? can occur with frequencies that differ by orders of magnitude. We also add thermal fluctuations to these stable configurations to understand the relationship between the frequency and shape of the potential landscape near the stable configurations.

Gao, Guo-Jie; Blawzdziewicz, Jerzy; O'Hern, Corey

2006-03-01

313

Electric-hydraulic car  

Microsoft Academic Search

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

R. W. Clark; H. Greene

1993-01-01

314

Free volume distribution of nearly jammed hard sphere packings  

NASA Astrophysics Data System (ADS)

We calculate the free volume distributions of nearly jammed packings of monodisperse and bidisperse hard sphere configurations. These distributions differ qualitatively from those of the fluid, displaying a power law tail at large free volumes, which constitutes a distinct signature of nearly jammed configurations, persisting for moderate degrees of decompression. We reproduce and explain the observed distribution by considering the pair correlation function within the first coordination shell for jammed hard sphere configurations. We analyze features of the equation of state near jamming, and discuss the significance of observed asphericities of the free volumes to the equation of state.

Maiti, Moumita; Sastry, Srikanth

2014-07-01

315

Free volume distribution of nearly jammed hard sphere packings.  

PubMed

We calculate the free volume distributions of nearly jammed packings of monodisperse and bidisperse hard sphere configurations. These distributions differ qualitatively from those of the fluid, displaying a power law tail at large free volumes, which constitutes a distinct signature of nearly jammed configurations, persisting for moderate degrees of decompression. We reproduce and explain the observed distribution by considering the pair correlation function within the first coordination shell for jammed hard sphere configurations. We analyze features of the equation of state near jamming, and discuss the significance of observed asphericities of the free volumes to the equation of state. PMID:25084929

Maiti, Moumita; Sastry, Srikanth

2014-07-28

316

Free volume distribution of nearly jammed hard sphere packings  

E-print Network

We calculate the free volume distributions of nearly jammed packings of monodisperse and bidisperse hard sphere configurations. These distributions differ qualitatively from those of the fluid, displaying a power law tail at large free volumes, which constitutes a distinct signature of nearly jammed configurations, persisting for moderate degrees of decompression. We reproduce and explain the observed distribution by considering the pair correlation function within the first coordination shell for jammed hard sphere configurations. We analyze features of the equation of state near jamming, and discuss the significance of observed asphericities of the free volumes to the equation of state.

Moumita Maiti; Srikanth Sastry

2014-07-25

317

Method for directional hydraulic fracturing  

DOEpatents

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.

Swanson, David E. (West St. Paul, MN); Daly, Daniel W. (Crystal, MN)

1994-01-01

318

Packed Bed Combustion: An Overview  

E-print Network

in pulp and paper plants - trash incineration - power gen. (eg Denmark) - small scale district energy systems using biomass Related processes: - gasification of coal or biomass - main difference is a much thicker bed - smelting iron in blast furnace or cupola Boiler for 50 t/h wood wastes and sludge (Bowater

Hallett, William L.H.

319

Electokinetic high pressure hydraulic system  

DOEpatents

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.

Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA)

2000-01-01

320

Numerical simulation of hydraulic transients  

NASA Astrophysics Data System (ADS)

A numerical method suitable for the analysis of hydraulic transients in one-dimensional pipelines as well as some applications of the method are presented in this thesis. In the present method one-dimensional flow equations are solved in a characteristic form using a finite difference technique. A nonequilibrium two-phase flow model is used, which makes it possible to analyze the effect of vaporization. The motion of the pipe-wall, which is important in some types of hydraulic transients, can be taken into account approximately. The main application of the method has been the piping of nuclear reactors.

Siikonen, T.

321

Modeling biooxidation of iron in packed-bed reactor  

SciTech Connect

Acid mine drainage (AMD) from active and abandoned mines continues to be an important source of water pollution in the US and around the world. AMD typically has high levels of acidity, sulfate, and metals. A model based on Monod kinetics and originally developed for use with rotating biological contactors was modified for use with a packed-bed column reactor. The reactor was filled with expanded polystyrene beads to immobilize chemolithotrophic bacteria and fed up to 570 mg L{sup {minus}1} ferrous iron [Fe(II)] in simulated acid mine drainage. A tracer study indicated changing behavior as a function of hydraulic residence time (HRT), with a transition from complete mix flow behavior to plug flow behavior as HRT decreased. The Fe(II) oxidation efficiency exceeded 95% until the HRT was reduced below 0.5 h. The reactor performance could be predicted with the model using estimates from the literature for {cflx u} and Y. The experimentally determined half-saturation constant K{sub s} was found to range from 5 to 12 mg L{sup {minus}1}. The maximum volumetric capacity constant R{sub max} was estimated to be {approximately}360 mg Fe(II)h{sup {minus}1} L{sup {minus}1} beads under complete mix flow conditions but appeared to be as high as 724 mg Fe(II)h{sup {minus}1} L{sup {minus}1} beads as conditions approached plug flow at short HRTs.

Diz, H.R. [Gannon Univ., Erie, PA (United States). Dept. of Environmental Science and Engineering] [Gannon Univ., Erie, PA (United States). Dept. of Environmental Science and Engineering; Novak, J.T. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)] [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)

1999-02-01

322

Robust Force Control of a 6-Link Electro-Hydraulic Manipulator  

NASA Astrophysics Data System (ADS)

Uninterrupted power supply has become indispensable during the maintenance task of active electric power lines as a result of today's highly information-oriented society and increasing demand of electric utilities. This maintenance task has the risk of electric shock and the danger of falling from high place. Therefore it is necessary to realize an autonomous robot system using electro-hydraulic manipulator because hydraulic manipulators have the advantage of electric insulation and power/mass density. Meanwhile an electro-hydraulic manipulator using hydraulic actuators has many nonlinear elements, and its parameter fluctuations are greater than those of an electrically driven manipulator. So it is relatively difficult to realize not only stable contact work but also accurate force control for the autonomous assembly tasks using hydraulic manipulators. In this paper, the robust force control of a 6-link electro-hydraulic manipulator system used in the real maintenance task of active electic line is examined in detail. A nominal model for the system is obtained from experimental frequency responses of the system, and the deviation of the manipulator system from the nominal model is derived by a multiplicative uncertainty. Robust disturbance observers for force control are designed using this information in an H? framework, and implemented on the two different setups. Experimental results show that highly robust force tracking by a 6-link electro-hydraulic manipulator could be achieved even if the stiffness of environment and the shape of wall change.

Ahn, Kyoungkwan; Yokota, Shinichi

323

Inverse modeling of hydraulic tests in fractured crystalline rock based on a transition probability geostatistical approach  

NASA Astrophysics Data System (ADS)

This paper presents numerical simulations of a series of hydraulic interference tests conducted in crystalline bedrock at Olkiluoto (Finland), a potential site for the disposal of the Finnish high-level nuclear waste. The tests are in a block of crystalline bedrock of about 0.03 km3 that contains low-transmissivity fractures. Fracture density, orientation, and fracture transmissivity are estimated from Posiva Flow Log (PFL) measurements in boreholes drilled in the rock block. On the basis of those data, a geostatistical approach relying on a transitional probability and Markov chain models is used to define a conceptual model based on stochastic fractured rock facies. Four facies are defined, from sparsely fractured bedrock to highly fractured bedrock. Using this conceptual model, three-dimensional groundwater flow is then simulated to reproduce interference pumping tests in either open or packed-off boreholes. Hydraulic conductivities of the fracture facies are estimated through automatic calibration using either hydraulic heads or both hydraulic heads and PFL flow rates as targets for calibration. The latter option produces a narrower confidence interval for the calibrated hydraulic conductivities, therefore reducing the associated uncertainty and demonstrating the usefulness of the measured PFL flow rates. Furthermore, the stochastic facies conceptual model is a suitable alternative to discrete fracture network models to simulate fluid flow in fractured geological media.

Blessent, Daniela; Therrien, René; Lemieux, Jean-Michel

2011-12-01

324

Hydraulic geometry of river cross sections; theory of minimum variance  

USGS Publications Warehouse

This study deals with the rates at which mean velocity, mean depth, and water-surface width increase with water discharge at a cross section on an alluvial stream. Such relations often follow power laws, the exponents in which are called hydraulic exponents. The Langbein (1964) minimum-variance theory is examined in regard to its validity and its ability to predict observed hydraulic exponents. The variables used with the theory were velocity, depth, width, bed shear stress, friction factor, slope (energy gradient), and stream power. Slope is often constant, in which case only velocity, depth, width, shear and friction factor need be considered. The theory was tested against a wide range of field data from various geographic areas of the United States. The original theory was intended to produce only the average hydraulic exponents for a group of cross sections in a similar type of geologic or hydraulic environment. The theory does predict these average exponents with a reasonable degree of accuracy. An attempt to forecast the exponents at any selected cross section was moderately successful. Empirical equations are more accurate than the minimum variance, Gauckler-Manning, or Chezy methods. Predictions of the exponent of width are most reliable, the exponent of depth fair, and the exponent of mean velocity poor. (Woodard-USGS)

Williams, Garnett P.

1978-01-01

325

Climbing robot actuated by meso-hydraulic artificial muscles  

NASA Astrophysics Data System (ADS)

This paper presents the design, construction, experimental characterization, and system testing of a legged, wall-climbing robot actuated by meso-scale hydraulic artificial muscles. While small wall-climbing robots have seen increased research attention in recent years, most authors have primarily focused on designs for the gripping and adhesion of the robot to the wall, while using only standard DC servo-motors for actuation. This project seeks to explore and demonstrate a different actuation mechanism that utilizes hydraulic artificial muscles. A four-limb climbing robot platform that includes a full closed-loop hydraulic power and control system, custom hydraulic artificial muscles for actuation, an on-board microcontroller and RF receiver for control, and compliant claws with integrated sensing for gripping a variety of wall surfaces has been constructed and is currently being tested to investigate this actuation method. On-board power consumption data-logging during climbing operation, analysis of the robot kinematics and climbing behavior, and artificial muscle force-displacement characterization are presented to investigate and this actuation method.

Bryant, Matthew; Fitzgerald, Jason; Miller, Samuel; Saltzman, Jonah; Kim, Sangkyu; Lin, Yong; Garcia, Ephrahim

2014-03-01

326

Design of a smart material electro-hydraulic actuator with improved frequency bandwidth  

NASA Astrophysics Data System (ADS)

Smart material electro-hydraulic actuators utilize fluid rectification by one-way valves to convert the small, high-frequency, high-force motions of smart materials such as piezoelectrics and magnetostrictives into useful motions of a hydraulic cylinder. These actuators have potential to replace centralized hydraulic pumps and lines with lightweight, compact, power-by-wire systems. This paper presents the design and testing of an improved actuator system. To increase the frequency bandwidth of operation, a lumped-parameter model is developed and validated based on experimental study of a pump with a performance capacity of 18.4 W. The critical parameters for pump performance are identified and their effect on pump performance assessed. The geometry of the hydraulic manifold that integrates the smart material pump and the output hydraulic cylinder is found to be critical for determining the effective system bandwidth.

Larson, John P.; Dapino, Marcelo J.

2012-04-01

327

23 CFR 650.111 - Location hydraulic studies.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 false Location hydraulic studies. 650.111 Section 650...STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650.111 Location hydraulic studies. (a) National...

2010-04-01

328

77 FR 55770 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...from the area of the landing gear's hydraulic power pack system. This proposed AD would require you inspect the aircraft's hydraulic power pack wiring for incorrect installation...from the area of the landing gear's hydraulic power pack system and resulted in a...

2012-09-11

329

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...

330

Hydraulic straight hole drill collar  

Microsoft Academic Search

An improved drill collar for forming relatively straight holes in crooked hole type formations. One or more hydraulic drill collars are connected in series relationship within a drill string above a rotary bit at the point of tangency. Each drill collar includes at least one outwardly opening, longitudinally extending slot formed on the exterior thereof. The slot includes a back

Townson

1985-01-01

331

Introduction to Hydraulics. Instructor's Guide.  

ERIC Educational Resources Information 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…

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

332

Introduction to Hydraulics. Student's Manual.  

ERIC Educational Resources Information 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…

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

333

Thermal-Hydraulic-Analysis Program  

NASA Technical Reports Server (NTRS)

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.

Walton, J. T.

1993-01-01

334

Ensemble smoother assimilation of hydraulic head and return flow data to estimate hydraulic conductivity distribution  

E-print Network

Ensemble smoother assimilation of hydraulic head and return flow data to estimate hydraulic and data measurements, an ensemble smoother (ES) to provide enhanced estimates of aquifer hydraulic conductivity (K) through assimilation of hydraulic head (H) and groundwater return flow volume (RFV

Bau, Domenico A.

335

Hydraulic conductivity imaging from 3-D transient hydraulic tomography at several pumping/observation densities  

E-print Network

Hydraulic conductivity imaging from 3-D transient hydraulic tomography at several pumping August 2013; accepted 7 September 2013; published 13 November 2013. [1] 3-D Hydraulic tomography (3-D HT (primarily hydraulic conductivity, K) is estimated by joint inversion of head change data from multiple

Barrash, Warren

336

A study on the position control of hydraulic cylinder driven by hydraulic transformer using disturbance observer  

Microsoft Academic Search

A hydraulic cylinder drive using a hydraulic transformer, which is considered as secondary controlled unit, is studied here. Using hydraulic transformer for driving a hydraulic cylinder should avoid energy loss via controlled valves and get benefit from recovery of the load potential. Position control, an important issue of the cylinder control is investigated in this paper. To obtain robust position

Ho Triet Hung; Ahn Kyoung Kwan

2008-01-01

337

Reducing hydraulic conductivity of porous media using CaCO3 precipitation induced by Sporosarcina pasteurii.  

PubMed

The effect on hydraulic conductivity in porous media of CaCO3 precipitation induced by Sporosarcina pasteurii (ATCC 11859) was investigated using continuous-flow columns containing glass beads between 0.01 mm and 3 mm in diameter. Resting S. pasteurii cells and a precipitation solution composed of 0.5 M CaCl2 and 0.5 M urea were introduced into the columns, and it was shown that the subsequent formation of CaCO3 precipitation reduced hydraulic conductivity from between 8.38 × 10(-1) and 3.27 × 10(-4) cm/s to between 3.70 × 10(-1) and 3.07 × 10(-5) cm/s. The bacterial cells themselves did not decrease the hydraulic conductivity. The amount of precipitation was proportional with the bacterial number in the column. The specific CaCO3 precipitation rate of the resting cells was estimated as 4.0 ± 0.1 × 10(-3) ?g CaCO3/cell. Larger amounts of CaCO3 precipitation were deposited in columns packed with small glass beads than in those packed with large glass beads, resulting in a greater reduction in the hydraulic conductivity of the columns containing small glass beads. Analysis using the Kozeny-Carman equation suggested that the effect of microbially induced CaCO3 precipitation on hydraulic conductivity was not due to the formation of individual CaCO3 crystals but instead that the precipitate aggregated with the glass beads, thus increasing their diameter and consequently decreasing the pore size in the column. PMID:25239069

Eryürük, Ka?an; Yang, Suyin; Suzuki, Daisuke; Sakaguchi, Iwao; Akatsuka, Tetsuji; Tsuchiya, Takayuki; Katayama, Arata

2015-03-01

338

Hydraulic characterization of " Furcraea andina  

NASA Astrophysics Data System (ADS)

The present level of pollution, increasingly involving groundwaters, constitutes a serious risk for environment and human health. Therefore the remediation of saturated and unsaturated soils, removing pollutant materials through innovative and economic bio-remediation techniques is more frequently required. Recent studies on natural fiber development have shown the effectiveness of these fibers for removal of some heavy metals, due to the lignin content in the natural fibers which plays an important role in the adsorption of metal cations (Lee et al., 2004; Troisi et al., 2008; C. Fallico, 2010). In the context of remediation techniques for unsaturated and/or saturated zone, an experimental approach for the hydraulic characterization of the "Furcraea andina" (i.e., Cabuya Blanca) fiber was carried out. This fiber is native to Andean regions and grows easily in wild or cultivated form in the valleys and hillsides of Colombia, Ecuador, and Peru. Fibers of "Furcraea andina" were characterized by experimental tests to determine their hydraulic conductivity or permeability and porosity in order to use this medium for bioremediation of contaminated aquifer exploiting the physical, chemical and microbial capacity of natural fiber in heavy metal adsorption. To evaluate empirically the hydraulic conductivity, laboratory tests were carried out at constant head specifically on the fibers manually extracted. For these tests we used a flow cell (used as permeameter), containing the "Furcraea andina" fibers to be characterized, suitably connected by a tygon pipe to a Marriott's bottle, which had a plastic tube that allow the adjustment of the hydraulic head for different tests to a constant value. By this experiment it was also possible to identify relationships that enable the estimation of permeability as a function of density, i.e. of the compaction degree of the fibers. Our study was carried out for three values of hydraulic head (H), namely 10, 18, and 25 cm and for each constant head we repeated the test for three different rate of fiber compaction within the flow cell, corresponding to three different densities (146 kg/m3, 200 kg/m3 and 240 kg/m3). We observed that with increasing density of the fibers there is an increase of hydraulic conductivity. The importance of the experimental results on permeability acquires greater relevance when compared to the values of hydraulic conductivity already known from the literature for different soils types. In this study, special attention has been given to the value of hydraulic conductivity of this fiber, considering that in the framework of groundwater remediation strategies if the hydraulic conductivity in the barrier is lower than that of the surrounding aquifer, the plume may change its natural pathway, bypassing the barrier and veering towards larger hydraulic conductivity. Reference • Lee, B. G. and Rowell, R. M.: Removal of heavy metal ions from aqueous solutions using lignocellulosic fibers, J. Natural Fibers, 1, 97-108, 2004. • Troisi, S., Fallico, C., Straface, S., and Mazzuca, L.: Biodreni per la bonifica di siti contaminati realizzati con fibre naturali liberiane ad elevato sviluppo superficiale. Brevetto dell'Università della Calabria (n.: CS2008A00018), 2008. • C. Fallico, S. Troisi, A. Molinari, and M. F. Rivera.: Characterization of broom fibers for PRB in the remediation of aquifers contaminated by heavy metals, Biogeosciences journal , 7, 2545-2556, 2010

Rivera-Velasquez, M. F.; Fallico, C.; Molinari, A.; Santillan, P.; Salazar, M.

2012-04-01

339

Regulation of Hydraulic Fracturing in California  

E-print Network

APRIL 2013 Regulation of Hydraulic Fracturing in California: A WAsteWAteR And WAteR QuAlity Pe | Regulation of Hydraulic Fracturing in California Wheeler Institute for Water Law & Policy Center for Law #12;Regulation of Hydraulic Fracturing in California | 3Berkeley law | wheeler InstItute for water law

Kammen, Daniel M.

340

4, 37193769, 2007 A model for hydraulic  

E-print Network

HESSD 4, 3719­3769, 2007 A model for hydraulic redistribution G. G. Amenu and P. Kumar Title Page are under open-access review for the journal Hydrology and Earth System Sciences A model for hydraulic;HESSD 4, 3719­3769, 2007 A model for hydraulic redistribution G. G. Amenu and P. Kumar Title Page

Paris-Sud XI, Université de

341

Numerical Study of a Turbulent Hydraulic Jump  

E-print Network

Numerical Study of a Turbulent Hydraulic Jump Qun Zhao, Shubhra Misra, Ib. A. Svendsen and James T of a Turbulent Hydraulic Jump ­ p.1/14 #12;Objective Our ultimate goal is to study the breaking waves. Numerical Study of a Turbulent Hydraulic Jump ­ p.2/14 #12;A moving bore Qiantang Bore China (Courtesy of Dr J

Zhao, Qun

342

LA-12968-MS The Unsaturated Hydraulic  

E-print Network

LA-12968-MS The Unsaturated Hydraulic Characteristics of the BandelierTuff LosN A T I O N A L L A B technical correctness. #12;The Unsaturated Hydraulic Characteristics of the Bandelier Tuff David B. Rogers........................................................................................................4 Hydraulic Data Presentation

343

Hydraulic Cooling Tower Driver- The Innovation  

E-print Network

-drive eliminates these items from the drive train and puts the same electric motor HP at ground level close coupled to a hydraulic pump, filters, and oil reservoir. Hydraulic lines bring oil pressure to the hydraulic motor, which is more than 75% less weight than...

Dickerson, J. A.

344

Hydraulic Fracture: multiscale processes and moving  

E-print Network

Hydraulic Fracture: multiscale processes and moving interfaces Anthony Peirce Department Mitchell (UBC) · Ed Siebrits (SLB, Houston) #12;2 Outline · What is a hydraulic fracture? · Scaling Fluid Proppant #12;6 An actual hydraulic fracture #12;7 HF experiment (Jeffrey et al CSIRO) #12;8 1D

Peirce, Anthony

345

Hydraulic Fracture: multiscale processes and moving  

E-print Network

Hydraulic Fracture: multiscale processes and moving interfaces Anthony Peirce Department Siebrits (SLB, Houston) #12;2 Outline · What is a hydraulic fracture? · Mathematical models of hydraulic fracture · Scaling and special solutions for 1-2D models · Numerical modeling for 2-3D problems

Peirce, Anthony

346

Hydraulic Fracturing in Michigan Integrated Assessment  

E-print Network

Hydraulic Fracturing in Michigan Integrated Assessment #12;Agenda · Welcome and introduction and timeline · Panel presentation and discussion · Facilitated Q & A · Closing remarks #12;Hydraulic Fracturing · Leverages resources IA BENEFITS Benefits of Integrated Assessment #12;Key Points: · Hydraulic Fracturing (HF

Kamat, Vineet R.

347

Optimize Bit Hydraulics for Minimum Cost Drilling  

Microsoft Academic Search

In a previous paper, the authors derived a condition for optimum bit hydraulics considering increases in rate of penetration (ROP), fuel costs and pump maintenance costs with increased bit hydraulics. This paper is an extension of the previous work and demonstrates practical application of the new hydraulics optimization method. Previously unpublished full scale laboratory drilling data obtained by the authors

H. H. Doiron; J. D. Deane

1983-01-01

348

Nonlinear Control of a Hydraulic Parallel Manipulator  

Microsoft Academic Search

An adaptive nonlinear controller is proposed for position tracking in hydraulic robots by adopting the backstepping methodology. Full system models including rigid body and hydraulic dynamics are incorporated in the design. The tracking errors are shown to be asymptotically stable in the presence of parametric uncertainties using Lyapunov analysis. The controller is applied to a Stewart type hydraulic manipulator. Simulation

Mohammad Reza Sirouspour; S. E. Salcudean

2001-01-01

349

Hydraulic conductivity tests on compacted clay  

Microsoft Academic Search

Permeability tests were performed in the laboratory on compacted clay to study the effects of type of permeameter, hydraulic anisotropy, diameter of test specimens, storage time, and desiccation cracking. Essentially identical hydraulic conductivities were measured with compaction-mold, consolidationcell, and flexible-wall permeameters. With good bonding between lifts, hydraulic conductivity was isotropic. Test specimens having a diameter of 15 cm were twice

Stephen S. Boynton; David E. Daniel

1985-01-01

350

Study on the Key Image Processing Technology in the Inspection of Packing Quality for Small-Pack Cigarettes  

Microsoft Academic Search

Image processing is a key factor in the inspection of packing quality by machine vision. Targeting the inspection of packing quality for small-pack cigarettes in tobacco enterprises, this paper proposes a series of key image processing techniques: a fast algorithm for small-pack edge collecting based on fast Hough transformation, an online differentiating algorithm based on GLCM parameters, and packing-flaw detection

Hu Fang-xia; He xin; Niu Tian-gui

2007-01-01

351

Two-dimensional packing in prolate granular materials.  

PubMed

We investigate the two-dimensional packing of extremely prolate (aspect ratio alpha=L/D>10) granular materials, comparing experiments with Monte Carlo simulations. The average packing fraction of particles with aspect ratio alpha=12 is 0.68+/-0.03. We quantify the orientational correlation of particles and find a correlation length of two particle lengths. The functional form of the orientational correlation is the same in both experiments and simulations which three orders of magnitude in aspect ratio, all decaying over a distance of two particle lengths. It is possible to identify voids in the pile with sizes ranging over two orders of magnitude. The experimental void distribution function is a power law with exponent -beta=-2.43+/-0.08. Void distributions in simulated piles do not decay as a power law, but do show a broad tail. We extend the simulation to investigate the scaling at very large aspect ratios. A geometric argument predicts the pile number density to scale as alpha(-2). Simulations do indeed scale this way, but particle alignment complicates the picture, and the actual number densities are quite a bit larger than predicted. PMID:12786141

Stokely, K; Diacou, A; Franklin, Scott V

2003-05-01

352

Thermal hydraulic analysis of advanced Pb-Bi cooled NPP using natural circulation  

NASA Astrophysics Data System (ADS)

We present thermal hydraulic analysis for a low power advanced nuclear reactor cooled by lead-bismuth eutectic. In this work is to study the thermal hydraulic analysis of a low power SPINNOR (Small Power Reactor, Indonesia, No On-site Refuelling) reactor with 125 MWth which a design a core with very small volume and fuel column height, resulting in a negative coolant temperature coefficient and very low channel pressure drop. And also at full power the heat can be completely removed by natural circulation in the primary circuit, thus eliminating the needs for pumps.

Novitrian, Su'ud, Zaki; Waris, Abdul

2012-06-01

353

Spontaneous Crystallization in Athermal Polymer Packings  

PubMed Central

We review recent results from extensive simulations of the crystallization of athermal polymer packings. It is shown that above a certain packing density, and for sufficiently long simulations, all random assemblies of freely-jointed chains of tangent hard spheres of uniform size show a spontaneous transition into a crystalline phase. These polymer crystals adopt predominantly random hexagonal close packed morphologies. An analysis of the local environment around monomers based on the shape and size of the Voronoi polyhedra clearly shows that Voronoi cells become more spherical and more symmetric as the system transits to the ordered state. The change in the local environment leads to an increase in the monomer translational contribution to the entropy of the system, which acts as the driving force for the phase transition. A comparison of the crystallization of hard-sphere polymers and monomers highlights similarities and differences resulting from the constraints imposed by chain connectivity. PMID:23263666

Karayiannis, Nikos Ch.; Foteinopoulou, Katerina; Laso, Manuel

2013-01-01

354

An integrated model of ring pack performance  

NASA Technical Reports Server (NTRS)

This paper describes an integrated model developed for the detailed characterization and simulation of piston ring pack behavior in internal combustion engines and the prediction of ring pack performance. The model includes comprehensive and coupled treatments of (1) ring-liner hydrodynamic and boundary lubrication and friction; (2) ring axial, radial, and (toroidal) twist dynamics; (3) inter-ring gas dynamics and blowby. The physics of each of these highly inter-related phenomena are represented by submodels, which are intimately coupled to form a design-oriented predictive tool aimed at the calculation of ring film thicknesses, ring motions, land pressures, engine friction, and blowby. The paper also describes the results of a series of analytical studies investigating effects of engine speed and load and ring pack design parameters, on ring motions, film thicknesses, and inter-ring pressures, as well as ring friction and blowby.

Keribar, R.; Dursunkaya, Z.; Flemming, M. F.

1991-01-01

355

Method for packed column separations and purifications  

SciTech Connect

The invention encompasses a method of packing and unpacking a column chamber. A mixture of a fluid and a matrix material are introduced through a column chamber inlet so that the matrix material is packed within a column chamber to form a packed column. The column chamber having the column chamber inlet or first port for receiving the mixture further has an outlet port and an actuator port. The outlet port is partially closed for capturing the matrix material and permitting the fluid to flow therepast by rotating relative one to the other of a rod placed in the actuator port. Further rotation relative one to the other of the rod and the column chamber opens the outlet and permits the matrix material and the fluid to flow therethrough thereby unpacking the matrix material from the column chamber.

Holman, David A. (Richland, WA); Bruckner-Lea, Cynthia J. (Richland, WA); Brockman, Fred J. (Kennewick, WA); Chandler, Darrell P. (Richland, WA)

2006-08-15

356

Hydraulic servo mechanism of automatic transmission for vehicle  

Microsoft Academic Search

In a vehicle having an automatic transmission, a hydraulic servo control mechanism is described comprising: a hydraulic pressure source, a hydraulic servo; an accumulator; a drain oil line; interconnecting passage means providing a fluid path from the hydraulic pressure source to the hydraulic servo and from the hydraulic servo to the drain oil line; a selector valve, connected in the

K. Sumiya; Y. Sakaguchi; Y. Taga; S. Kubo; S. Moroto

1988-01-01

357

Suggested Packing List for Bahamian Conservation Biology Study Abroad Summer 2013  

E-print Network

SUGGESTIONS Notebook, pencils, pens Mask, snorkel, fins, and mesh bag Plastic drinking container / water compensator with power inflator Alternate air source Depth and submersible pressure gauges Mask, snorkel pack in medium-sized soft-sided duffel bags if possible (NO HARD-SIDED SUITCASES). You will have a 40

Langerhans, Brian

358

Suggested Packing List for Bahamian Conservation Biology Study Abroad Summer 2014  

E-print Network

SUGGESTIONS Notebook, pencils, pens Mask, snorkel, fins, and mesh bag Plastic drinking container / water) Regulator, Octopus Buoyancy compensator with power inflator Alternate air source Depth and submersible Luggage: Forfar requests that you please pack in medium-sized soft-sided duffel bags if possible (NO HARD

Langerhans, Brian

359

Confined packings of frictionless spheres and polyhedra  

NASA Astrophysics Data System (ADS)

By means of numerical simulations, we study the influence of confinement on three-dimensional random close packed (RCP) granular materials subject to gravity. The effects of grain shape (spherical or polyhedral) and polydispersity on this dependence are investigated. In agreement with a simple geometrical model, the solid fraction is found to decrease linearly for increasing confinement no matter the grain shape. This decrease remains valid for bidisperse sphere packings although the gradient seems to reduce significantly when the proportion of small particles reaches 40% by volume. The aforementioned model is extended to capture the effect of the confinement on the coordination number.

Camenen, Jean-François; Descantes, Yannick; Richard, Patrick

2013-06-01

360

Why is random close packing reproducible?  

PubMed

We link the thermodynamics of colloidal suspensions to the statistics of regular and random packings. Random close packing has defied a rigorous definition yet, in three dimensions, there is near universal agreement on the volume fraction at which it occurs. We conjecture that the common value of phi{rcp} approximately 0.64 arises from a divergence in the rate at which accessible states disappear. We relate this rate to the equation of state for a hard-sphere fluid on a metastable, noncrystalline branch. PMID:17995178

Kamien, Randall D; Liu, Andrea J

2007-10-12

361

Why is Random Close Packing Reproducible?  

E-print Network

We link the thermodynamics of colloidal suspensions to the statistics of regular and random packings. Random close packing has defied a rigorous definition yet, in three dimensions, there is near universal agreement on the volume fraction at which it occurs. We conjecture that the common value of phi_rcp, approximately 0.64, arises from a divergence in the rate at which accessible states disappear. We relate this rate to the equation of state for a hard sphere fluid on a metastable, non-crystalline branch.

Randall D. Kamien; Andrea J. Liu

2007-08-27

362

Angularly anisotropic correlation in granular packings  

NASA Astrophysics Data System (ADS)

We present an x-ray microtomography study of the three-dimensional structural correlations in monodisperse granular packings. By measuring an orientation-dependent pair correlation function, we find that the local structure shows an angularly anisotropic orientation correlation. The correlation is strongest along the major axis of the local Minkowski tensor of the Voronoi cell. It turns out that this anisotropic correlation is consistent with the existence of some locally favored structures. The study suggests the importance of high-order structural correlations in random granular packings.

Xia, Chengjie; Cao, Yixin; Kou, Binquan; Li, Jindong; Wang, Yujie; Xiao, Xianghui; Fezzaa, Kamel

2014-12-01

363

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

SciTech Connect

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.

Not Available

1988-01-01

364

Optimised Iteration in Coupled Monte Carlo - Thermal-Hydraulics Calculations  

NASA Astrophysics Data System (ADS)

This paper describes an optimised iteration scheme for the number of neutron histories and the relaxation factor in successive iterations of coupled Monte Carlo and thermal-hydraulic reactor calculations based on the stochastic iteration method. The scheme results in an increasing number of neutron histories for the Monte Carlo calculation in successive iteration steps and a decreasing relaxation factor for the spatial power distribution to be used as input to the thermal-hydraulics calculation. The theoretical basis is discussed in detail and practical consequences of the scheme are shown, among which a nearly linear increase per iteration of the number of cycles in the Monte Carlo calculation. The scheme is demonstrated for a full PWR type fuel assembly. Results are shown for the axial power distribution during several iteration steps. A few alternative iteration method are also tested and it is concluded that the presented iteration method is near optimal.

Hoogenboom, J. Eduard; Dufek, Jan

2014-06-01

365

Thermal Hydraulic Analysis of HTGR Coupled with Hydrogen Plant  

SciTech Connect

The US Department of Energy is investigating the use of high-temperature gas-cooled reactors (HTGR) to produce electricity and hydrogen. Although the hydrogen production processes using the nuclear energy are in an early stage of development, coupling hydrogen plant to HTGR requires both efficient heat transfer and adequate separation of the facilities to assure that off-normal events in the production facility do not impact the nuclear plant. In anticipation of the design, development and procurement of an advanced power conversion system for HTGR, this study was initiated to identify the major design and technology options and their tradeoffs in the evaluation of power conversion system (PCS) coupled to hydrogen plant. In this study, we investigated a number of design configurations and performed thermal hydraulic analyses using various working fluids and various conditions. This paper includes a portion of thermal hydraulic results based on a direct cycle and a parallel intermediate heat exchanger (IHX) configuration option.

Chang Oh; Cliff Davis; Robert Barner; Paul Pickard

2006-06-01

366

PASSIVE CONTROL OF FLUID POWERED HUMAN POWER AMPLIFIERS  

E-print Network

PASSIVE CONTROL OF FLUID POWERED HUMAN POWER AMPLIFIERS Perry Y. Li and Venkat Durbha Center is proposed for the control of fluid powered human power amplifiers. Human power amplifiers are mechanical tools that humans operate directly and the human force is amplified hydraulically or pneumatically

Li, Perry Y.

367

The application of hydraulics in the 2,000 kW wind turbine generator  

NASA Technical Reports Server (NTRS)

A 2000 kW turbine generator using hydraulic power in two of its control systems is being built under the management of NASA Lewis Research Center. The hydraulic systems providing the control torques and forces for the yaw and blade pitch control systems are discussed. The yaw-drive-system hydraulic supply provides the power for positioning the nacelle so that the rotary axis is kept in line with the direction of the prevailing wind, as well as pressure to the yaw and high speed shaft brakes. The pitch-change-mechanism hydraulic system provides the actuation to the pitch change mechanism and permits feathering of the blades during an emergency situation. It operates in conjunction with the overall windmill computer system, with the feather control permitting slewing control flow to pass from the servo valve to the actuators without restriction.

Onufreiczuk, S.

1978-01-01

368

Hydraulic blowdown TVA system for the Castor 120 motor program  

NASA Astrophysics Data System (ADS)

The performance and reliability of a low-cost hydraulic blowdown system for expendable launch vehicles (ELVs) are demonstrated in the context of the Castro 120 motor program. Test results are reported which show that the blowdown system meets or exceeds the performance objectives for an ELV motor in a Stage I, Stage II, or strap-on application. The primary cost savings include replacement of the expensive turbine pump and auxiliary power source and the use of a simplified actuator design.

Lee, R. G.; Olsen, G. E.; Trowbridge, C. G.; Griffis, D. M.

1993-06-01

369

Pressure solution creep of random packs of spheres  

NASA Astrophysics Data System (ADS)

performed numerical calculations of compaction in aggregates of spherical grains, using Lehner and Leroy's (2004, hereinafter LL) constitutive model of pressure solution at grain contacts. That model is founded on a local definition of the thermodynamic driving force and leads to a fully coupled formulation of elastic deformation, dissolution, and diffusive transport along the grain boundaries. The initial geometry of the aggregate was generated by random packing of spheres with a small standard deviation of the diameters. During the simulations, isostatic loading was applied. The elastic displacements at the contacts were calculated according to Digby's (1981) nonlinear contact force model, and deformation by dissolution was evaluated using the LL formulation. The aggregate strain and porosity were tracked as a function of time for fixed temperature, applied effective pressure, and grain size. We also monitored values of the average and standard deviation of total load at each contact, the coordination number for packing, and the statistics of the contact dimensions. Because the simulations explicitly exclude processes such as fracturing, plastic flow, and transport owing to surface curvature, they can be used to test the influence of relative changes in the kinetics of dissolution and diffusion processes caused by contact growth and packing rearrangements. We found that the simulated strain data could be empirically fitted by two successive power laws of the form, ?x ? t?, where ? was equal to 1 at very early times, but dropped to as low as 0.3 at longer times. The apparent sensitivity of strain rate to stress found in the simulations was much lower than predicted from constitutive laws that assume a single dominant process driven by average macroscopic loads. Likewise, the apparent activation enthalpy obtained from the simulated data was intermediate between that assumed for dissolution and diffusion, and, further, tended to decrease with time. These results are similar to the experimental observations of Visser et al.'s (2012), who used an aggregate geometry and physical conditions closely resembling the present numerical simulations.

Bernabé, Y.; Evans, B.

2014-05-01

370

Name That Shell! ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-15

371

High-angle gravel pack completion studies  

SciTech Connect

A two-part study was conducted to define optimum gravel pack procedures and completion design factors for high-angle wells. In the first part of the study, gravel slurries were pumped through an 1100 ft tubing string to simulate actual slurry transport conditions in high-angle wells. The tubing string had an inclination of 80/sup 0/ from vertical. Measurements were made to determine suitable viscosity and solids concentration for effective gravel transport. In the second part of the study a cased hole completion model was constructed at full scale. Gravel slurries that had satisfactory transport performance were tested for packing characteristics in the model wellbore (completion interval). Need for special completion interval geometric considerations to obtain satisfactory packs was investigated. Results of this study showed that high viscosity carrier fluids (600-700 cp) with high gravel concentrations (15 lbm/gal) provide good transport, but they are unsuitable for use in completion intervals in wells with angles of 80/sup 0/ from vertical. Satisfactory transport and improved packing were achieved with lower carrier viscosity and concentration (300-400 cp, 4 lbm/ gal). Special liner-tailpipe (washpipe) geometry considerations reported by previous investigators are required in conjunction with the optimum slurry properties defined in this study. Completion operations designed using results from this study have satisfactorily met general placement criteria. Field experience to date has been in wells with inclinations up to 70/sup 0/ from vertical.

Elson, T.D.; Darlington, R.M.; Mantooth, M.A.

1983-03-01

372

St Catharine's College MCR Welcome Pack  

E-print Network

St Catharine's College MCR Welcome Pack 2012-2013 #12;Contents 1. Letter From The MCR Committee 2. Meet the MCR Committee 3. Freshers' To Do List: When You Arrive... 4. Important Information you to the Middle Combination Room (MCR), which refers to both a room in College and the community

Travis, Adrian

373

29 CFR 784.135 - “Packing.”  

Code of Federal Regulations, 2013 CFR

...wooden boxes, as in the case of shrimp, or placing the product in wooden boxes and covering with seaweed as in the case of lobsters. Where the trips are of long duration, as for several weeks or more, packing the operations on fishing vessels...

2013-07-01

374

29 CFR 784.135 - “Packing.”  

Code of Federal Regulations, 2014 CFR

...wooden boxes, as in the case of shrimp, or placing the product in wooden boxes and covering with seaweed as in the case of lobsters. Where the trips are of long duration, as for several weeks or more, packing the operations on fishing vessels...

2014-07-01

375

Simple Cloud Chambers Using Gel Ice Packs  

ERIC Educational Resources Information Center

Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry…

Kamata, Masahiro; Kubota, Miki

2012-01-01

376

7 CFR 51.3152 - Standard pack.  

Code of Federal Regulations, 2010 CFR

...Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be of the proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end of the fruit....

2010-01-01

377

7 CFR 51.3152 - Standard pack.  

Code of Federal Regulations, 2011 CFR

...Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be of the proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end of the fruit....

2011-01-01

378

7 CFR 51.2338 - Standard pack.  

Code of Federal Regulations, 2011 CFR

... (1) Fruit packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end. (f) In order...

2011-01-01

379

That Magnetic Dog ClassPack  

NSDL National Science Digital Library

Using More Picture-Perfect Science Lessons: Using Children's Books to Guide Inquiry, K-4 in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatche

2010-04-24

380

Leadership in Wolf, Canis lupus, Packs  

NSDL National Science Digital Library

The Northern Prairie Wildlife Research Center (NPWRC) continues to place scientific/ management resources online for general viewing. L. David Mech recently published this article in Canadian Field-Naturalist [114(2):259-263, 2000] describing leadership in wolf packs. It may be browsed online or downloaded as a .zip file.

Mech, L. David.

381

bring pack-ages or lug-  

E-print Network

ABOUT BOSS can i bring pack- ages or lug- gage on my ride? all carry on baggage must fit in your on my ride? students with a valid id can bring two guests into the van. NOTE BOSS MISSION state law advanced docu- mentation. 1.call 414.229.6503 or stop in at the boss office. 6. always wear your seat belt

Saldin, Dilano

382

Sheep in a Jeep ClassPack  

NSDL National Science Digital Library

Using Picture-Perfect Science Lessons in your classroom is easier than ever! NSTA's ClassPacks, each sufficient for a class of 28 students, are lesson-specific collections of materials--an unmatched time-saver and a great deal. This Cla

2010-04-21

383

Stuffed Derivatives of Close-Packed Structures  

ERIC Educational Resources Information Center

Decades ago Buerger described and later Palmer reviewed stuffed silica crystal structures widely used by mineralogists. Many publications and books have discussed common crystal structures in terms of close-packing of one set of atoms or ions (P sites) with other atoms or ions in tetrahedral (T) or octahedral (O) sites. Douglas and Ho described…

Douglas, Bodie E.

2007-01-01

384

7 CFR 51.310 - Packing requirements.  

Code of Federal Regulations, 2010 CFR

...means that apples are of the proper size for molds or cell compartments in which they are packed, and that molds or cells are filled in such a way that no more than slight movement of apples within molds or cells is possible. 3...

2010-01-01

385

7 CFR 51.310 - Packing requirements.  

Code of Federal Regulations, 2012 CFR

...means that apples are of the proper size for molds or cell compartments in which they are packed, and that molds or cells are filled in such a way that no more than slight movement of apples within molds or cells is possible. 3...

2012-01-01

386

7 CFR 51.310 - Packing requirements.  

Code of Federal Regulations, 2013 CFR

...means that apples are of the proper size for molds or cell compartments in which they are packed, and that molds or cells are filled in such a way that no more than slight movement of apples within molds or cells is possible. 3...

2013-01-01

387

7 CFR 51.310 - Packing requirements.  

Code of Federal Regulations, 2014 CFR

...means that apples are of the proper size for molds or cell compartments in which they are packed, and that molds or cells are filled in such a way that no more than slight movement of apples within molds or cells is possible. 3...

2014-01-01

388

7 CFR 51.310 - Packing requirements.  

Code of Federal Regulations, 2011 CFR

...means that apples are of the proper size for molds or cell compartments in which they are packed, and that molds or cells are filled in such a way that no more than slight movement of apples within molds or cells is possible. 3...

2011-01-01

389

Radiological and practical aspects of body packing.  

PubMed

Body packing represents the concealment of illegal substances in a person's body with the aim of smuggling. "Body packers" either swallow drug-filled packets or introduce drug-filled packets into their bodies rectally or vaginally with the purpose of concealing them. The three main smuggled drugs are cocaine, heroin and cannabis products. Body packing represents a serious risk of acute narcotic toxicity from drug exposure, intestinal obstruction owing to pellet impaction and bowel perforation with consequent abdominal sepsis. A suspected body packer is generally admitted to hospital to perform imaging investigations and confirm the presence of drugs in his/her body. Radiological imaging methods are essential to diagnose body packing and to detect potential complications. Increasing sophistication of traffickers and improvements in packaging add to the detection difficulty. Radiologists should be aware of the appearance of drug packets in a range of imaging modalities. This article informs physicians about the challenging aspects of body packing, its background and medicolegal issues, what imaging methods can be used and what criteria are necessary to perform a correct diagnosis. PMID:24472727

Pinto, A; Reginelli, A; Pinto, F; Sica, G; Scaglione, M; Berger, F H; Romano, L; Brunese, L

2014-04-01

390

The benefits of using customized procedure packs.  

PubMed

Discrete item purchasing is the traditional approach for hospitals to obtain consumable supplies for theatre procedures. Although most items are relatively low cost, the management and co-ordination of the supply chain, raising orders, controlling stock, picking and delivering to each operating theatre can be complex and costly. Customized procedure packs provide a solution. PMID:11892113

Baines, R; Colquhoun, G; Jones, N; Bateman, R

2001-01-01

391

PROTEIN RECOVERY FROM BEEF PACKING EFFLUENT  

EPA Science Inventory

The wastewater from a beef packing plant contained 4,600 mg/1 COD and 2,500 mg/1 of suspended solids. A physiochemical wastewater treatment process that recovers protein removed 80% of the oxygen demand and suspended solids, and 94% of the fat, oil, and grease. Total cost was $3 ...

392

7 CFR 51.2338 - Standard pack.  

Code of Federal Regulations, 2013 CFR

... (1) Fruit packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end. (f) In order...

2013-01-01

393

7 CFR 51.3152 - Standard pack.  

Code of Federal Regulations, 2014 CFR

...Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be of the proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end of the fruit....

2014-01-01

394

7 CFR 51.2338 - Standard pack.  

Code of Federal Regulations, 2014 CFR

... (1) Fruit packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end. (f) In order...

2014-01-01

395

7 CFR 51.3152 - Standard pack.  

Code of Federal Regulations, 2013 CFR

...Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be of the proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end of the fruit....

2013-01-01

396

7 CFR 51.2338 - Standard pack.  

Code of Federal Regulations, 2012 CFR

... (1) Fruit packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end. (f) In order...

2012-01-01

397

7 CFR 51.3152 - Standard pack.  

Code of Federal Regulations, 2012 CFR

...Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be of the proper size for the cells, fillers, or molds in which they are...measured at right angles to a line from stem to blossom end of the fruit....

2012-01-01

398

Ecology of Southern Ocean pack ice  

Microsoft Academic Search

Around Antartica the annual five-fold growth and decay of sea ice is the most prominent physical process and has a profound impact on marine life there. In winter the pack ice canopy extends to cover almost 20 million square kilometres — some 8% of the southern hemisphere and an area larger than the Antarctic continent itself (13.2 million square kilometres)

Andrew S Brierley; David N Thomas

2002-01-01

399

Porous bead packings for gas chromatography  

NASA Technical Reports Server (NTRS)

Porous polyaromatic packing beads have low polarity, high efficiency, short retention time, and may be synthesized in size range of 50 to 150 micrometers (100 to 270 mesh). Mechanically strong beads may be produced using various materials depending on elements and compounds to be identified.

Pollock, G. E.; Woeller, F. H.

1979-01-01

400

Modal analysis of hydraulic pipelines  

NASA Astrophysics Data System (ADS)

The laminar flow of a weakly compressible Newtonian fluid in a pipeline is treated by modal methods, aiming at a theoretical basis for the experimental modal analysis of hydraulic pipelines. For two points located at arbitrary positions along a pipeline, the frequency response function between flow rate excitation and pressure response is calculated in closed form, expanded into a modal series including transcendental modal transfer functions, and approximated by finite sums of rational fraction expressions. The preferred modal approximation is recognized as mobility function of a structurally damped mechanical multi-degrees-of-freedom system. Experimental modal analysis procedures for structurally and viscously damped mechanical systems are adapted for hydraulic pipelines and pipeline systems.

Mikota, Gudrun

2013-08-01

401

Advanced energy saving hydraulic elevator  

SciTech Connect

An hydraulic elevator is described comprising: a counterweighted elevator comprising a car, a counterweight, and a rope connecting the car and the counterweight; a ram having a first reaction surface for driving one of the car or the counterweight upwardly and a second reaction surface for driving one of the car or the counterweight downwardly; multiplier means for moving the car a distance greater than a stroke of the ram, the multiplier means connecting the ram to the counterweighted elevator, the multiplier means comprising: a first pulley; a second pulley; means for rigidly connecting the first and second pulley, the means having a length corresponding to a rise of the hydraulic elevator, the means attaching to the ram; and a pulley rope which: has a first end attaching to a first fixed point, extends about the first pulley, extends about the second pulley, and has a second end attaching to a second fixed point.

Garrido, A.; Sevilleja, J.; Servia, A.

1993-08-24

402

Hydraulic conductivity of rice roots.  

PubMed

A pressure chamber and a root pressure probe technique have been used to measure hydraulic conductivities of rice roots (root Lp(r) per m(2) of root surface area). Young plants of two rice (Oryza sativa L.) varieties (an upland variety, cv. Azucena and a lowland variety, cv. IR64) were grown for 31-40 d in 12 h days with 500 micromol m(-2) s(-1) PAR and day/night temperatures of 27 degrees C and 22 degrees C. Root Lp(r) was measured under conditions of steady-state and transient water flow. Different growth conditions (hydroponic and aeroponic culture) did not cause visible differences in root anatomy in either variety. Values of root Lp(r) obtained from hydraulic (hydrostatic) and osmotic water flow were of the order of 10(-8) m s(-1) MPa(-1) and were similar when using the different techniques. In comparison with other herbaceous species, rice roots tended to have a higher hydraulic resistance of the roots per unit root surface area. The data suggest that the low overall hydraulic conductivity of rice roots is caused by the existence of apoplastic barriers in the outer root parts (exodermis and sclerenchymatous (fibre) tissue) and by a strongly developed endodermis rather than by the existence of aerenchyma. According to the composite transport model of the root, the ability to adapt to higher transpirational demands from the shoot should be limited for rice because there were minimal changes in root Lp(r) depending on whether hydrostatic or osmotic forces were acting. It is concluded that this may be one of the reasons why rice suffers from water shortage in the shoot even in flooded fields. PMID:11520872

Miyamoto, N; Steudle, E; Hirasawa, T; Lafitte, R

2001-09-01

403

GCFR thermal-hydraulic experiments  

SciTech Connect

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

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

1980-01-01

404

Hydraulic redistribution may stimulate decomposition  

Microsoft Academic Search

Roots influence root litter decomposition through multiple belowground processes. Hydraulic lift or redistribution (HR) by\\u000a plants is one such process that creates diel drying–rewetting cycles in soil. However, it is unclear if this phenomenon influences\\u000a decomposition. Since decomposition in deserts is constrained by low soil moisture and is stimulated when dry soils are rewetted,\\u000a we hypothesized that diel drying–rewetting, via

Zachary T. Aanderud; James H. Richards

2009-01-01

405

Fluid Power Technician  

ERIC Educational Resources Information Center

Fluid power technicians, sometimes called hydraulic and pneumatic technicians, work with equipment that utilizes the pressure of a liquid or gas in a closed container to transmit, multiply, or control power. Working under the supervision of an engineer or engineering staff, they assemble, install, maintain, and test fluid power equipment.…

Moore, Pam

2008-01-01

406

14 CFR 27.695 - Power boost and power-operated control system.  

Code of Federal Regulations, 2013 CFR

...mechanical system. The power portion includes the power source (such as hydraulic pumps), and such items as valves, lines, and actuators. (c) The failure of mechanical parts (such as piston rods and links), and the jamming of power cylinders, must...

2013-01-01

407

14 CFR 27.695 - Power boost and power-operated control system.  

Code of Federal Regulations, 2014 CFR

...mechanical system. The power portion includes the power source (such as hydraulic pumps), and such items as valves, lines, and actuators. (c) The failure of mechanical parts (such as piston rods and links), and the jamming of power cylinders, must...

2014-01-01

408

Chain Packing and Trajectory of Isotactic Polypropylene ? Crystals studied by Solid-State NMR  

NASA Astrophysics Data System (ADS)

Isotactic polypropylene (ipp) is one of the simplest polyolefins and the crystalline structures, have been extensively studied. Ipp crystallizes as ? form via isothermal crystallization from the melt state. Packing structures of ? form has been used as structural markers of crystallization process. With the development of high resolution solid-state NMR (SS-NMR) technique, it becomes a powerful tool to investigate order-disorder of chain packing in the crystalline regions. We performed a series of experiments on different samples crystallized at different temperatures and studied the formation of ? crystals influenced by different parameters, such as molecular weight, catalyst type and stereo, region regularity. Using selectively ^13C enriched ipp samples we detect inter-nuclear correlations between the neighboring stems. This information provides chain reentry information. We figure out relationship between the chain reentry and chain packing of ipp ? crystals. The recent discovery of the ipp ?2 single crystal offers a great opportunity to understand this topic also.

Li, Zhen; Cao, Yan; Miyoshi, Toshikazu; Cheng, Stephen

2012-02-01

409

36 CFR 34.10 - Saddle and pack animals.  

Code of Federal Regulations, 2011 CFR

... 34.10 Section 34.10 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR EL PORTAL ADMINISTRATIVE SITE REGULATIONS § 34.10 Saddle and pack animals. The use of saddle and pack animals is prohibited...

2011-07-01

410

36 CFR 34.10 - Saddle and pack animals.  

Code of Federal Regulations, 2010 CFR

... 34.10 Section 34.10 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR EL PORTAL ADMINISTRATIVE SITE REGULATIONS § 34.10 Saddle and pack animals. The use of saddle and pack animals is prohibited...

2010-07-01

411

7 CFR 51.2840 - Export packing requirements.  

Code of Federal Regulations, 2011 CFR

...CERTIFICATION, AND STANDARDS) United States Standards for Grades of Onions (Other Than Bermuda-Granex-Grano and Creole Types) Export...Requirements § 51.2840 Export packing requirements. Onions specified as meeting Export Packing Requirements shall...

2011-01-01

412

7 CFR 51.2840 - Export packing requirements.  

Code of Federal Regulations, 2013 CFR

...CERTIFICATION, AND STANDARDS) United States Standards for Grades of Onions (Other Than Bermuda-Granex-Grano and Creole Types) Export...Requirements § 51.2840 Export packing requirements. Onions specified as meeting Export Packing Requirements shall be...

2013-01-01

413

7 CFR 51.1271 - Tolerances for standard pack.  

Code of Federal Regulations, 2010 CFR

...FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1271 Tolerances for standard pack. (a) In order to allow for variations incident...

2010-01-01

414

7 CFR 51.1271 - Tolerances for standard pack.  

Code of Federal Regulations, 2011 CFR

...FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Summer and Fall Pears 1 Standard Pack § 51.1271 Tolerances for standard pack. (a) In order to allow for variations incident...

2011-01-01

415

Frictionless bead packs have macroscopic friction, but no dilatancy  

NASA Astrophysics Data System (ADS)

The statement of the title is shown by numerical simulation of homogeneously sheared assemblies of frictionless, nearly rigid beads in the quasistatic limit. Results coincide for steady flows at constant shear rate ?? in the limit of small ?? and static approaches, in which packings are equilibrated under growing deviator stresses. The internal friction angle ? , equal to 5.76°±0.22° in simple shear, is independent of average pressure P in the rigid limit and stems from the ability of stable frictionless contact networks to form stress-induced anisotropic fabrics. No enduring strain localization is observed. Dissipation at the macroscopic level results from repeated network rearrangements, similar to the effective friction of a frictionless slider on a bumpy surface. Solid fraction ? remains equal to the random close packing value ?0.64 in slowly or statically sheared systems. Fluctuations of stresses and volume are observed to regress in the large system limit. Defining the inertial number as I=??m/(aP) , with m the grain mass and a its diameter, both internal friction coefficient ??=tan? and volume 1/? increase as powers of I in the quasistatic limit of vanishing I , in which all mechanical properties are determined by contact network geometry. The microstructure of the sheared material is characterized with a suitable parametrization of the fabric tensor and measurements of coordination numbers.

Peyneau, Pierre-Emmanuel; Roux, Jean-Noël

2008-07-01

416

Content-Aware Photo Collage Using Circle Packing.  

PubMed

In this paper, we present a novel approach for automatically creating the photo collage that assembles the interest regions of a given group of images naturally. From the geometric point of view, we recast the generation of collage as a region partition problem such that each image is displayed in its corresponding region partitioned from the canvas. The core of this is an efficient power diagram based circle packing algorithm, which arranges a series of circles assigned to input photos compactly in the given canvas. To favor important photos, the circles are associated with image importances determined by an image ranking process. A heuristic search process is developed to ensure that salient information of each photo is displayed in the polygonal area resulting from circle packing. With our new formulation, each factor influencing the state of a photo is optimized in an independent stage, and computation of the optimal states for neighboring photos are completely decoupled. This improves the scalability of collage results and ensures their diversity. Our approach can generate the collages on non-rectangular canvases and supports interactive collage. We conduct extensive experiments and show the superiority of our algorithm by comparing against previous methods. PMID:23898016

Yu, Zongqiao; Lu, Lin; Guo, Yanwen; Fan, Rongfei; Liu, Mingming; Wang, Wenping

2013-07-25

417

ANS sixth proceedings of the nuclear thermal hydraulics  

SciTech Connect

This book is covered under the following topics: Thermal Hydraulics of Severe Accidents; Thermal Hydraulics of Noncommercial Reactors; Thermal Hydraulic Aspects of Passive Safety and New-Generation Reactors; Method s In Reactor Physics and Thermal Hydraulics; Thermal Hydraulics - Numerical Techniques In Reactor System Thermal Hydraulic; Advancements In Radionuclide Thermal Hydraulics; Fundamentals of Two-Phase Flows; and Natural Circulation In Reactor Systems-I-II.

Not Available

1990-01-01

418

Evaluation of Packed Columns in Supercritical Extraction Processes  

E-print Network

--------- EVALUATION OF PACKED COLUMNS IN SUPERCRITICAL EXTRACTION PROCESSES Paul J. Rathkamp, James R. Fair, Jimmy L. Humphrey The University of Texas at Austin Austin, Texas ABSTRACT The purpose of the present work is to add to the base... of knowledge in the use of packed columns when used in supercritical extraction service. Ex perimental studies were performed on a one-inch di ameter supercritical fluid extraction column oper ated in both spray and packed column arrangements. The packing...

Rathkamp, P. J.; Fair, J. R.; Humphrey, J. L.

419

PILOT-SCALE HYDRAULIC TESTING OF RESORCINOL FORMALDEHYDE ION EXCHANGE RESIN  

SciTech Connect

Savannah River National Laboratory (SRNL) performed pilot-scale hydraulic/chemical testing of spherical resorcinol formaldehyde (RF) ion exchange (IX) resin for the River Protection Project-Hanford Tank Waste Treatment & Immobilization Plant (WTP) Project. The RF resin hydraulic cycle testing was conducted in two pilot-scale IX columns, 1/4 and 1/2 scale. A total of twenty-three hydraulic/chemical cycles were successfully completed on the spherical RF resin. Sixteen of these cycles were completed in the 24-inch IX Column (1/2 scale column). Hydraulic testing showed that the permeability of the RF resin remained essentially constant, with no observed trend in the reduction of the permeability as the number of cycles increased. The permeability during the pilot-scale testing was 3 times better than the design requirements of the WTP full-scale IX system. The RF resin bed showed no tendency to form fissures or pack more densely as the number of cycles increased. Particle size measurements of the RF resin showed no indication of particle size change (for a given chemical) with cycles and essentially no fines formation. The permeability of the resin bed was uniform with respect to changes in bed depth. Upflow Regeneration and Simulant Introduction in the IX columns revealed another RF resin benefit; negligible radial pressures to the column walls from the swelling of resin beads. The hydraulic and chemical performance of the spherical RF resin during cycle testing was found to be superior to all other tested IX resins. The pilot-scale testing indicates that the RF resin is durable and should hold up to many hydraulic cycles in actual radioactive Cesium (Cs) separation.

Adamson, D.

2009-05-28

420

Circle packings of maps in polynomial time Bojan Mohar  

E-print Network

Circle packings of maps in polynomial time Bojan Mohar Department of Mathematics University of Ljubljana Jadranska 19, 1111 Ljubljana Slovenia Abstract The Andreev-Koebe-Thurston circle packing theorem is generalized and improved in two ways. First, we get simultaneous circle packings of the map and its dual map

Mohar, Bojan

421

Conformally Symmetric Circle Packings: A Generalization of Doyle's Spirals  

E-print Network

Conformally Symmetric Circle Packings: A Generalization of Doyle's Spirals Alexander I. Bobenko and Tim Hoffmann CONTENTS 1. Introduction 2. Geometry of Circle Flowers and Conformally Symmetric Circle Packings 3. Analytic Description of Conformally Symmetric Circle Packings 4. Doyle Spirals 5. Airy

Bobenko, Alexander I.

422

A CIRCLE PACKING ALGORITHM CHARLES R. COLLINS AND KENNETH STEPHENSON  

E-print Network

A CIRCLE PACKING ALGORITHM CHARLES R. COLLINS AND KENNETH STEPHENSON #3; Abstract. A circle packing is a con#12;guration P of circles realizing a speci#12;ed pattern of tangen- cies. Radii of packings. A central role is played by new and subtle monotonicity results for \\ owers" of circles. Key words. circle

Stephenson, Kenneth

423

A symmetry treatment of Danzerian rigidity for circle packing  

E-print Network

A symmetry treatment of Danzerian rigidity for circle packing BY P. W. FOWLER 1,*, S. D. GUEST 2 is derived and applied to the spherical circle-packing problem. The known scalar counting rule for Danzerian, and in several cases lead to new local optima. Keywords: circle packing; symmetry; rigidity 1. Introduction

Guest, Simon

424

1. Contextual view looking west, showing packing house and Union ...  

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

1. Contextual view looking west, showing packing house and Union Ice building, which is located to the north of Packing House (right hand side in photo) - College Heights Lemon Packing House, 519-532 West First Street, Claremont, Los Angeles County, CA

425

21 CFR 890.5730 - Moist heat pack.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food...Medicine Therapeutic Devices § 890.5730 Moist heat pack. (a) Identification. A moist heat pack is a device intended for medical...

2011-04-01

426

21 CFR 890.5730 - Moist heat pack.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food...Medicine Therapeutic Devices § 890.5730 Moist heat pack. (a) Identification. A moist heat pack is a device intended for medical...

2013-04-01

427

21 CFR 890.5730 - Moist heat pack.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food...Medicine Therapeutic Devices § 890.5730 Moist heat pack. (a) Identification. A moist heat pack is a device intended for medical...

2012-04-01

428

21 CFR 890.5730 - Moist heat pack.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food...Medicine Therapeutic Devices § 890.5730 Moist heat pack. (a) Identification. A moist heat pack is a device intended for medical...

2010-04-01

429

21 CFR 890.5730 - Moist heat pack.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food...Medicine Therapeutic Devices § 890.5730 Moist heat pack. (a) Identification. A moist heat pack is a device intended for medical...

2014-04-01

430

Robust Force Control of a 6Link Electro-Hydraulic Manipulator  

Microsoft Academic Search

Uninterrupted power supply has become indispensable during the maintenance task of active electric power lines as a result of today's highly information-oriented society and increasing demand of electric utilities. This maintenance task has the risk of electric shock and the danger of falling from high place. Therefore it is necessary to realize an autonomous robot system using electro-hydraulic manipulator because

Kyoungkwan Ahn; Shinichi Yokota

2003-01-01

431

Hydraulic Energy Storage Based Hybrid Propulsion System For A Terrestrial Vehicle  

Microsoft Academic Search

Three classes of hydraulic hybrid systems -- the pure hydrostatic, the hydro-mechanical, and the power assist -- have been modeled, analyzed, and their behavior over EPA driving and performance schedules simulated. mance potential has been established. The class of “power assist” systems was identified as one showing the greatest potential for passenger car application and was, therefore, analyzed in greater

L. O. Hewko; T. R. Weber

1990-01-01

432

Numerically simulating the thermal–hydraulic characteristics within the fuel rod bundle using CFD methodology  

Microsoft Academic Search

With the dramatic progress in the computer processing power, computational fluid dynamics (CFD) methodology can be applied in investigating the detailed knowledge of thermal–hydraulic characteristics in the rod bundle, especially with the spacer grid. These localized information, including flow, turbulence, and heat transfer characteristics, etc., can assist in the design and the improvement of rod bundles for nuclear power plants.

C. C. Liu; Y. M. Ferng

2010-01-01

433

Combined hydraulic and regenerative braking system  

DOEpatents

A combined hydraulic and regenerative braking system and method for an electric vehicle, with the braking system being responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

Venkataperumal, Rama R. (Troy, MI); Mericle, Gerald E. (Mount Clemens, MI)

1981-06-02

434

Commercialization Effort for 1W Consumer Electronics Power Pack  

SciTech Connect

A commercial ready fuel cell charger has been further developed, demonstrated, and field tested during the three phases of this project. The work performed and demonstrated has shown the commercialization readiness of this future product and underlying technology. The tasks in phase 1 of the project focused on component cost reduction, redesign for manufacturability, performance & reliability testing, and system integration. The end of phase 1 was completed on time and was signified by passing the Go/No-Go checkpoint. As shown in the report all technical metrics have been met or exceeded and the Go/No-Go checkpoint was passed in November of 2009. The tasks in phase 2 focused on tool fabrication and tooled component prove-out in working systems. The end of Phase 2 was the accomplishment of building working systems made almost completely of tooled components. The tasks in phase 3 of the project were preparing for and executing a 75 unit field test of the DMFC charger product developed in Phase 1 and phase 2. This field test demonstrated the functionality of the DMFC in the hands of real users while also providing feedback for potential design improvements. This was the first time a significant number of MTI units were put into the field to test usability and functionality. Feedback from the field test was positive and the units functioned well in the field.

Carlstrom, Charles, M.

2011-06-29

435

Electricity generation and microbial community changes in microbial fuel cells packed with different anodic materials.  

PubMed

Four materials, carbon felt cube (CFC), granular graphite (GG), granular activated carbon (GAC) and granular semicoke (GS) were tested as packed anodic materials to seek a potentially practical material for microbial fuel cells (MFCs). The microbial community and its correlation with the electricity generation performance of MFCs were explored. The maximum power density was found in GAC, followed by CFC, GG and GS. In GAC and CFC packed MFCs, Geobacter was the dominating genus, while Azospira was the most populous group in GG. Results further indicated that GAC was the most favorable for Geobacter adherence and growth, and the maximum power densities had positive correlation with the total biomass and the relative abundance of Geobacter, but without apparent correlation with the microbial diversity. Due to the low content of Geobacter in GS, power generated in this system may be attributed to other microorganisms such as Synergistes, Bacteroidetes and Castellaniella. PMID:21983409

Sun, Yanmei; Wei, Jincheng; Liang, Peng; Huang, Xia

2011-12-01

436

Hydraulic control system for an infinitely variable belt-drive transmission  

SciTech Connect

This patent describes a system for controlling the transmission ratio of an infinitely variable transmission for transmitting the power of an internal combustion engine comprising a primary pulley having a hydraulically shiftable disc and a hydraulic cylinder for shifting the disc, a secondary pulley having a hydraulically shiftable disc and a hydraulic cylinder for operating the latter disc, a belt engaged with both pulleys, and a pressure oil circuit having a pump for supplying pressurized oil. A transmission ratio control valve has a spool responsive to engine speed for controlling the pressurized oil so as to move the disc of the primary pulley to change the transmission ratio. The improvement described here comprises: a hydraulic circuit for applying control oil to one end of the spool of the transmission ratio control valve so as to axially move the spool for the controlling of the pressurized oil; an electronic control circuit responsive to ignition pulses of the engine for producing an output signal dependent on the engine speed; a modulator valve provided in the hydraulic circuit for producing a constant pressure of the control oil; an electromagnetic valve provided in the hydraulic circuit and having a coil responsive to the output signal for controlling the constant pressure of the control oil applied to the spool of the transmission ratio control valve, thereby to control the transmission ratio.

Takano, T.; Sakakiyama, R.

1987-02-24

437

Fault Detection and Isolation for Hydraulic Control  

NASA Technical Reports Server (NTRS)

Pressure sensors and isolation valves act to shut down defective servochannel. Redundant hydraulic system indirectly senses failure in any of its electrical control channels and mechanically isolates hydraulic channel controlled by faulty electrical channel so flat it cannot participate in operating system. With failure-detection and isolation technique, system can sustains two failed channels and still functions at full performance levels. Scheme useful on aircraft or other systems with hydraulic servovalves where failure cannot be tolerated.

1987-01-01

438

Is incest common in gray wolf packs?  

USGS Publications Warehouse

Wolf packs generally consist of a breeding pair and their maturing offspring that help provision and protect pack young. Because the reproductive tenure in wolves often is short, reproductively mature offspring might replace their parents, resulting in sibling or parent-offspring matings. To determine the extent of incestuous pairings, we measure relatedness based on variability in 20 microsatellite loci of mated pairs, parent-offspring pairs and siblings in two populations of gray wolves. Our 16 sampled mated pairs had values of relatedness not overlapping those of known parent-offspring or sibling dyads, which is consistent with their being unrelated or distantly related. These results suggest that full siblings or a parent and their offspring rarely mate and that incest avoidance is an important constraint on gray wolf behavioral ecology.

Smith, D.; Meier, T.; Geffen, E.; Mech, L.D.; Burch, J.W.; Adams, L.G.; Wayne, R.K.

1997-01-01

439

USDC based rapid penetrator of packed soil  

NASA Technical Reports Server (NTRS)

Environment protection requires more testing and analysis tools. To detect buried chemical containers or other objects embedded in soil and avoid possible damages of them, a penetrator of packed soil operated using low pushing force was developed. The design was based on a novel driving mechanism of the ultrasonic/sonic driller/corer (USDC) device developed in the NDEAA lab at JPL [Bar-Cohen et al 2001, Bao et al 2003]. In the penetrator, a small free-flying mass is energized by a piezoelectric transducer and impacts a rod probe on its shoulder at frequencies of hundreds times per second. The impacts help the probe to penetrate the packed soil rapidly. A great reduction of the needed pushing force for penetration was achieved. The details of the design of the prototype penetrator and the results of performance tests are presented.

Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Badescu, Mircea

2006-01-01

440

Typical steam generator tube rupture (SGTR) effect on thermo-hydraulic parameters of VVER-1000 primary loop  

Microsoft Academic Search

In operation of nuclear power plant, it is very important to evaluate different accident scenarios in actual plant conditions. One of the main accidents is (SGTR) steam generator tube rupture in the field of nuclear safety. In this research variation of thermo-hydraulics parameters in primary loop under SGTR accident in VVER-1000 nuclear power plant is analyzed by Relap5\\/Mod 3.2 thermo-hydraulics

A. Zare; M. R. Nematollahi; K. Hadad; M. A. Mozaffari

441

Packing and Hausdorff Measures of Stable Trees  

Microsoft Academic Search

\\u000a In this paper we discuss Hausdorff and packing measures of random continuous trees called stable trees. Stable trees form\\u000a a specific class of Lévy trees (introduced by Le Gall and Le Jan in [33]) that contains Aldous’s continuum random tree which\\u000a corresponds to the Brownian case. We provide results for the whole stable trees and for their level sets that

Thomas Duquesne

2010-01-01

442

Packing C60 in Boron Nitride Nanotubes  

Microsoft Academic Search

We have created insulated C60 nanowire by packing C60 molecules into the interior of insulating boron nitride nanotubes (BNNTs). For small-diameter BNNTs, the wire consists of a linear chain of C60 molecules. With increasing BNNT inner diameter, unusual C60 stacking configurations are obtained (including helical, hollow core, and incommensurate) that are unknown for bulk or thin-film forms of C60. C60

W. Mickelson; S. Aloni; Wei-Qiang Han; John Cumings; A. Zettl

2003-01-01

443

Hydraulic impacts of hydrokinetic energy extraction in rivers  

NASA Astrophysics Data System (ADS)

A simple technique to estimate the hydraulic impacts associated with the deployment of hydrokinetic (HK) devices is introduced. This technique involves representing HK devices with an enhanced bottom roughness. The enhanced bottom roughness is found to be a function of Manning roughness, slope, and water depth of the natural channel as well as device efficiency, blockage ratio, and density of device deployment. This approach was developed using a theoretical relationship between power extracted to power dissipated, and assuming a simple rectangular channel cross-section and uniform distribution of devices. Once the effective bottom roughness is determined, it can be used to determine the hydraulic impact of arbitrary device configurations and flow situations. The enhanced bottom roughness approach was compared to an alternative method of determining the affects of hydrokinetic energy extraction (SNL-EFDC). Both methods were in good agreement. Capabilities and limitations of determining hydraulic impacts by enhanced bottom roughness approach are demonstrated by site-specific simulation for the Tanana site.

Kartezhnikova, Maria

444

Hydraulic control apparatus for a continuously variable transmission  

SciTech Connect

A hydraulic control apparatus is described for controlling a RPM of an engine in a motor vehicle using a continuously variable transmission. The transmission has a driving pulley mounted in an input shaft, the driving pulley comprising a fixed member and a movable member. The movable member is actuated by a hydraulic cylinder to form a V-shaped opening between the movable member and the fixed member. A driven pulley is mounted on an output shaft. The driven pulley comprises another fixed member and another movable member. The another movable member is similarly actuated by another hydraulic cylinder supplied with a line pressure to form another v-shaped opening between the another movable member and the another fixed member and an endless belt member spanning the pulleys so that an effective diameter of the pulleys can be varied with regard to each other so that different speed ratios can be obtained. The apparatus comprises: a first torque sensing means for detecting an input torque on the input shaft of the driving pulley generated by the power stroke of the engine and for outputting an input torque signal. The first torque sensing means is in communication with the input shaft; a second torque sensing means for detecting an output torque on the output shaft of the driven pulley generated by the power stroke of the engine and for outputting an output torque signal. The second torque sensing means is in communication with the output shaft; and a control circuit.

Tokoro, S.; Shigematsu, T.; Watanabe, T.

1986-12-23

445

Hydraulic control apparatus for a continuously variable transmission  

SciTech Connect

A hydraulic control apparatus is described for controlling a RPM of an engine in a motor vehicle using a continuously variable transmission. The transmission has a driving pulley mounted on an input shaft. The driving pulley comprises a fixed member and a moveable member. The moveable member is actuated by a hydraulic cylinder to form a V-shaped opening between the moveable member and the fixed member. A driven pulley is mounted on an output shaft. The driven pulley comprises another fixed member and another moveable member. Another moveable member is similarly actuated by another hydraulic cylinder supplied with a line pressure to form another V-shaped opening between another moveable member and another fixed member. An endless belt member spans the driving and driven pulleys so that an effective diameter of the pulleys can be varied with regard to each other so that different speed ratios can be obtained comprising: first detecting means for detecting a first phase of a frequency component of an input torque on the input shaft of the driving pulley generated by the power stroke of the engine, and for outputting an input torque signal; second detecting means for detecting a second phase of a frequency component of an output torque on the output shaft of the driven pulley generated by the power stroke of the engine, and for outputting an output torque signal.

Tokoro, S.; Shigematsu, T.; Watanabe, T.

1987-06-16

446

Monitoring hydraulic fracture growth: Laboratory experiments  

SciTech Connect

The authors carry out small-scale hydraulic fracture experiments to investigate the physics of hydraulic fracturing. The laboratory experiments are combined with time-lapse ultrasonic measurements with active sources using both compressional and shear-wave transducers. For the time-lapse measurements they focus on ultrasonic measurement changes during fracture growth. As a consequence they can detect the hydraulic fracture and characterize its shape and geometry during growth. Hence, this paper deals with fracture characterization using time-lapse acoustic data. Hydraulic fracturing is used in the oil and gas industry to stimulate reservoir production.

Groenenboom, J.; Dam, D.B. van

2000-04-01

447

Hydraulically Driven Grips For Hot Tensile Specimens  

NASA Technical Reports Server (NTRS)

Pair of grips for tensile and compressive test specimens operate at temperatures up to 1,500 degrees F. Grips include wedges holding specimen inside furnace, where heated to uniform temperature. Hydraulic pistons drive wedges, causing them to exert clamping force. Hydraulic pistons and hydraulic fluid remain outside furnace, at room temperature. Cooling water flows through parts of grips to reduce heat transferred to external components. Advantages over older devices for gripping specimens in high-temperature tests; no need to drill holes in specimens, maintains constant gripping force on specimens, and heated to same temperature as that of specimen without risk of heating hydraulic fluid and acuator components.

Bird, R. Keith; Johnson, George W.

1994-01-01

448

Hydraulic Extractor For Electronic Connectors  

NASA Technical Reports Server (NTRS)

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.

Smith, Larry D.

1994-01-01

449

Probe with integrated heater and thermocouple pack  

DOEpatents

A probe for measuring heat includes an elongate rod fitted within a sheath, and a plurality of annular recesses are formed on the surface of the rod in a spaced-apart relationship to form annular chambers that are resistant to heat flow. A longitudinal bore extends axially into the rod and within the cylinders defined by the annular chambers, and an integrated heater and thermocouple pack is dimensioned to fit within the bore. In construction, the integrated pack includes a plurality of wires disposed in electrical insulation within a sheath and a heater cable. These wires include one common wire and a plurality of thermocouple wires. The common wire is constructed of one type of conductive material while the thermocouple wires are each constructed of two types of materials so that at least one thermocouple junction is formed therein. All of the wires extend the length of the integrated pack and are connected together at their ends. The thermocouple wires are constructed to form thermocouple junctions proximate to each annular chamber for producing electromotive forces corresponding to the temperature of the rod within the annular chambers relative to outside the chambers. In the preferred embodiment, each thermocouple wire forms two thermocouple junctions, one junction being disposed within an annular chamber and the second junction being disposed outside of, but proximate to, the same annular chamber. In one embodiment two thermocouple wires are configured to double the sensitivity of the probe in one region.

McCulloch, Reginald W. (Oak Ridge, TN); Dial, Ralph E. (Concord, TN); Finnell, Wilber K. R. (Kingston, TN)

1988-01-01

450

Probe with integrated heater and thermocouple pack  

DOEpatents

A probe for measuring heat includes an elongate rod fitted within a sheath, and a plurality of annular recesses are formed on the surface of the rod in a spaced-apart relationship to form annular chambers that are resistant to heat flow. A longitudinal bore extends axially into the rod and within the cylinders defined by the annular chambers, and an integrated heater and thermocouple pack is dimensioned to fit within the bore. In construction, the integrated pack includes a plurality of wires disposed in electrical insulation within a sheath and a heater cable. These wires include one common wire and a plurality of thermocuple wires. The common wire is constructed of one type of conductive material while the thermocouple wires are each constructed of two types of materials so that at least one thermocouple junction is formed therein. All of the wires extend the length of the integrated pack and are connected together at their ends. The thermocouple wires are constructed to form thermocouple junctions proximate to each annular chamber for producing electromotive forces corresponding to the temperature of the rod within the annular chambers relative to outside the chambers. In the preferred embodiment, each thermocouple wire forms two thermocouple junctions, one junction being disposed within an annular chamber and the second junction being disposed outside of, but proximate to, the same annular chamber. In one embodiment two thermocouple wires are configured to double the sensitivity of the probe in one region.

McCulloch, Reg W. (Oak Ridge, TN); Dial, Ralph E. (Concord, TN); Finnell, Wilber K. R. (Kingston, TN)

1990-01-01

451

Dynamics of random packings in granular flow.  

PubMed

We present a multiscale simulation algorithm for amorphous materials, which we illustrate and validate in a canonical case of dense granular flow. Our algorithm is based on the recently proposed spot model, where particles in a dense random packing undergo chainlike collective displacements in response to diffusing "spots" of influence, carrying a slight excess of interstitial free volume. We reconstruct the microscopic dynamics of particles from the "coarse grained" dynamics of spots by introducing a localized particle relaxation step after each spot-induced block displacement, simply to enforce packing constraints with a (fairly arbitrary) soft-core repulsion. To test the model, we study to what extent it can describe the dynamics of up to 135,000 frictional, viscoelastic spheres in granular drainage simulated by the discrete-element method (DEM). With only five fitting parameters (the radius, volume, diffusivity, drift velocity, and injection rate of spots), we find that the spot simulations are able to largely reproduce not only the mean flow and diffusion, but also some subtle statistics of the flowing packings, such as spatial velocity correlations and many-body structural correlations. The spot simulations run over 100 times faster than the DEM and demonstrate the possibility of multiscale modeling for amorphous materials, whenever a suitable model can be devised for the coarse-grained spot dynamics. PMID:16802932

Rycroft, Chris H; Bazant, Martin Z; Grest, Gary S; Landry, James W

2006-05-01

452

Confined granular packings: structure, stress, and forces.  

PubMed

The structure and stresses of static granular packs in cylindrical containers are studied by using large-scale discrete element molecular dynamics simulations in three dimensions. We generate packings by both pouring and sedimentation and examine how the final state depends on the method of construction. The vertical stress becomes depth independent for deep piles and we compare these stress depth profiles to the classical Janssen theory. The majority of the tangential forces for particle-wall contacts are found to be close to the Coulomb failure criterion, in agreement with the theory of Janssen, while particle-particle contacts in the bulk are far from the Coulomb criterion. In addition, we show that a linear hydrostaticlike region at the top of the packings unexplained by the Janssen theory arises because most of the particle-wall tangential forces in this region are far from the Coulomb yield criterion. The distributions of particle-particle and particle-wall contact forces P(f) exhibit exponential-like decay at large forces in agreement with previous studies. PMID:12786358

Landry, James W; Grest, Gary S; Silbert, Leonardo E; Plimpton, Steven J

2003-04-01

453

Understanding Hydraulic Processes Primary Investigator: Frank H. Quinn  

E-print Network

Understanding Hydraulic Processes Primary Investigator: Frank H. Quinn Overview The hydraulic and connecting channel hydraulics models for use in Great Lakes water resource studies. 2000 Plans Niagara River Hydraulic Studies: Detailed analysis of the impact of hydraulic regime changes in the Niagara River

454

Dynamics and Model-Based Control of Electric Power Steering Systems.  

E-print Network

??Many automobile manufacturers are switching to Electric Power Steering (EPS) systems for their better performance and cost advantages over traditional Hydraulic Power Steering (HPS) systems.… (more)

Naser, Mehrabi

2014-01-01

455

March 3-4, 2008/ARR Power Management Technical Working Group  

E-print Network

temperature (armor+structure) - Thermal-hydraulic behavior at power producing conditions - Armor mass loss and Power Conversion") 2. Key science challenges (theory + experiments) - Material thermomechanics at high

Raffray, A. René

456

Non-Euclidean geometry of twisted filament bundle packing  

PubMed Central

Densely packed and twisted assemblies of filaments are crucial structural motifs in macroscopic materials (cables, ropes, and textiles) as well as synthetic and biological nanomaterials (fibrous proteins). We study the unique and nontrivial packing geometry of this universal material design from two perspectives. First, we show that the problem of twisted bundle packing can be mapped exactly onto the problem of disc packing on a curved surface, the geometry of which has a positive, spherical curvature close to the center of rotation and approaches the intrinsically flat geometry of a cylinder far from the bundle center. From this mapping, we find the packing of any twisted bundle is geometrically frustrated, as it makes the sixfold geometry of filament close packing impossible at the core of the fiber. This geometrical equivalence leads to a spectrum of close-packed fiber geometries, whose low symmetry (five-, four-, three-, and twofold) reflect non-Euclidean packing constraints at the bundle core. Second, we explore the ground-state structure of twisted filament assemblies formed under the influence of adhesive interactions by a computational model. Here, we find that the underlying non-Euclidean geometry of twisted fiber packing disrupts the regular lattice packing of filaments above a critical radius, proportional to the helical pitch. Above this critical radius, the ground-state packing includes the presence of between one and six excess fivefold disclinations in the cross-sectional order. PMID:22711799

Bruss, Isaac R.; Grason, Gregory M.

2012-01-01

457

Study of hydraulic air compression for Ocean Thermal Energy Conversion open-cycle application  

NASA Astrophysics Data System (ADS)

A hydraulic air compressor, which requires no mechanical moving parts and operates in a nearly isothermal mode, can be an alternative for the noncondensible gas disposal of an Ocean Thermal Energy Conversion (OTEC) open-cycle power system. The compressor requires only a downward flow of water to accomplish air compression. An air compressor test loop was assembled and operated to obtain test data that would lead to the design of an OTEC hydraulic air compressor. A one dimensional, hydraulic gas compressor, computer model was employed to simulate the laboratory experiments, and it was tuned to fit the test results. A sensitivity study that shows the effects of various parameters on the applied head of the hydraulic air compression is presented.

Golshani, A.; Chen, F. C.

1983-01-01

458

An evaluation of a hubless inducer and a full flow hydraulic turbine driven inducer boost pump  

NASA Technical Reports Server (NTRS)

The purpose of the study was to compare the performance of several configurations of hubless inducers with a hydrodynamically similar conventional inducer and to demonstrate the performance of a full flow hydraulic turbine driven inducer boost pump using these inducers. A boost pump of this type consists of an inducer connected to a hydraulic turbine with a high speed rotor located in between. All the flow passes through the inducer, rotor, and hydraulic turbine, then into the main pump. The rotor, which is attached to the main pump shaft, provides the input power to drive the hydraulic turbine which, in turn, drives the inducer. The inducer, rotating at a lower speed, develops the necessary head to prevent rotor cavitation. The rotor speed is consistent with present main engine liquid hydrogen pump designs and the overall boost pump head rise is sufficient to provide adequate main pump suction head. This system would have the potential for operating at lower liquid hydrogen tank pressures.

Lindley, B. K.; Martinson, A. R.

1971-01-01

459

Model for polygonal hydraulic jumps.  

PubMed

We propose a phenomenological model for the polygonal hydraulic jumps discovered by Ellegaard and co-workers [Nature (London) 392, 767 (1998); Nonlinearity 12, 1 (1999); Physica B 228, 1 (1996)], based on the known flow structure for the type-II hydraulic jumps with a "roller" (separation eddy) near the free surface in the jump region. The model consists of mass conservation and radial force balance between hydrostatic pressure and viscous stresses on the roller surface. In addition, we consider the azimuthal force balance, primarily between pressure and viscosity, but also including nonhydrostatic pressure contributions from surface tension in light of recent observations by Bush and co-workers [J. Fluid Mech. 558, 33 (2006); Phys. Fluids 16, S4 (2004)]. The model can be analyzed by linearization around the circular state, resulting in a parameter relationship for nearly circular polygonal states. A truncated but fully nonlinear version of the model can be solved analytically. This simpler model gives rise to polygonal shapes that are very similar to those observed in experiments, even though surface tension is neglected, and the condition for the existence of a polygon with N corners depends only on a single dimensionless number ?. Finally, we include time-dependent terms in the model and study linear stability of the circular state. Instability occurs for sufficiently small Bond number and the most unstable wavelength is expected to be roughly proportional to the width of the roller as in the Rayleigh-Plateau instability. PMID:22587189

Martens, Erik A; Watanabe, Shinya; Bohr, Tomas

2012-03-01

460

Control rod drive hydraulic system  

DOEpatents

A hydraulic system for a control rod drive (CRD) includes a variable output-pressure CR pump operable in a charging mode for providing pressurized fluid at a charging pressure, and in a normal mode for providing the pressurized fluid at a purge pressure, less than the charging pressure. Charging and purge lines are disposed in parallel flow between the CRD pump and the CRD. A hydraulic control unit is disposed in flow communication in the charging line and includes a scram accumulator. An isolation valve is provided in the charging line between the CRD pump and the scram accumulator. A controller is operatively connected to the CRD pump and the isolation valve and is effective for opening the isolation valve and operating the CRD pump in a charging mode for charging the scram accumulator, and closing the isolation valve and operating the CRD pump in a normal mode for providing to the CRD through the purge line the pressurized fluid at a purge pressure lower than the charging pressure.

Ose, Richard A. (San Jose, CA)

1992-01-01

461

TRANSLATING AVAILABLE BASIC SOIL DATA INTO MISSING SOIL HYDRAULIC CHARACTERISTICS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soil hydraulic pedotransfer functions transfer simple-to-measure soil survey information into soil hydraulic characteristics, that are otherwise costly to measure. Examples are presented of different equations describing hydraulic characteristics and of pedotransfer functions used to predict paramet...

462

Soil Hydraulic Characteristics of a Small Southwest Oregon Watershed Following  

E-print Network

--------------------------------------------- Soil Hydraulic Characteristics of a Small Southwest by a high-intensity burn over areas of steep topography. The areal distribution of soil hydraulic of infiltration capacity, saturated hydraulic conductivity, and soil moisture characteristics. Also, measures

Standiford, Richard B.

463

Effective hydraulic conductivity of bounded, strongly heterogeneous porous media  

E-print Network

Effective hydraulic conductivity of bounded, strongly heterogeneous porous media Evangelos K of Arizona, Tucson Abstract. We develop analytical expressions for the effective hydraulic conductivity Ke boundaries. The log hydraulic conductivity Y forms a Gaussian, statistically homogeneous and anisotropic

Tartakovsky, Daniel M.

464

Scaling hydraulic properties of a macroporous soil Binayak P. Mohanty  

E-print Network

Scaling hydraulic properties of a macroporous soil Binayak P. Mohanty U.S. Salinity Laboratory, Riverside, California Abstract. Macroporous soils exhibit significant differences in their hydraulic properties for different pore domains. Multimodal hydraulic functions may be used to describe

Mohanty, Binayak P.

465

7 CFR 3201.10 - Mobile equipment hydraulic fluids.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Mobile equipment hydraulic fluids. 3201...PROCUREMENT Designated Items § 3201.10 Mobile equipment hydraulic fluids. (a) Definition...procurement preference for qualifying biobased mobile equipment hydraulic fluids. By...

2012-01-01

466

7 CFR 3201.10 - Mobile equipment hydraulic fluids.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Mobile equipment hydraulic fluids. 3201...PROCUREMENT Designated Items § 3201.10 Mobile equipment hydraulic fluids. (a) Definition...procurement preference for qualifying biobased mobile equipment hydraulic fluids. By...

2014-01-01

467

7 CFR 3201.10 - Mobile equipment hydraulic fluids.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Mobile equipment hydraulic fluids. 3201...PROCUREMENT Designated Items § 3201.10 Mobile equipment hydraulic fluids. (a) Definition...procurement preference for qualifying biobased mobile equipment hydraulic fluids. By...

2013-01-01

468

23 CFR 650.111 - Location hydraulic studies.  

Code of Federal Regulations, 2013 CFR

...FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650.111 Location hydraulic studies....

2013-04-01

469

23 CFR 650.111 - Location hydraulic studies.  

Code of Federal Regulations, 2011 CFR

...FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650.111 Location hydraulic studies....

2011-04-01

470

23 CFR 650.111 - Location hydraulic studies.  

Code of Federal Regulations, 2012 CFR

...FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650.111 Location hydraulic studies....

2012-04-01

471

23 CFR 650.111 - Location hydraulic studies.  

Code of Federal Regulations, 2014 CFR

...FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650.111 Location hydraulic studies....

2014-04-01

472

7 CFR 2902.10 - Mobile equipment hydraulic fluids.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Mobile equipment hydraulic fluids. 2902.10 Section 2902.10...Designated Items § 2902.10 Mobile equipment hydraulic fluids. (a) Definition. Hydraulic fluids formulated for general use in...

2010-01-01

473

7 CFR 2902.28 - Stationary equipment hydraulic fluids.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Stationary equipment hydraulic fluids. 2902.28 Section 2902...2902.28 Stationary equipment hydraulic fluids. (a) Definition. Fluids formulated for use in stationary hydraulic equipment systems that...

2010-01-01

474

21 CFR 880.5110 - Hydraulic adjustable hospital bed.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Hydraulic adjustable hospital bed. 880.5110...Therapeutic Devices § 880.5110 Hydraulic adjustable hospital bed. (a) Identification. A hydraulic adjustable hospital bed is a...

2010-04-01

475

14 CFR 33.72 - Hydraulic actuating systems.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 2010-01-01 false Hydraulic actuating systems. 33.72 Section 33...Construction; Turbine Aircraft Engines § 33.72 Hydraulic actuating systems. Each hydraulic actuating system must function...

2010-01-01

476

Mapping the distribution of packing topologies within protein interiors shows predominant preference for specific packing motifs  

PubMed Central

Background Mapping protein primary sequences to their three dimensional folds referred to as the 'second genetic code' remains an unsolved scientific problem. A crucial part of the problem concerns the geometrical specificity in side chain association leading to densely packed protein cores, a hallmark of correctly folded native structures. Thus, any model of packing within proteins should constitute an indispensable component of protein folding and design. Results In this study an attempt has been made to find, characterize and classify recurring patterns in the packing of side chain atoms within a protein which sustains its native fold. The interaction of side chain atoms within the protein core has been represented as a contact network based on the surface complementarity and overlap between associating side chain surfaces. Some network topologies definitely appear to be preferred and they have been termed 'packing motifs', analogous to super secondary structures in proteins. Study of the distribution of these motifs reveals the ubiquitous presence of typical smaller graphs, which appear to get linked or coalesce to give larger graphs, reminiscent of the nucleation-condensation model in protein folding. One such frequently occurring motif, also envisaged as the unit of clustering, the three residue clique was invariably found in regions of dense packing. Finally, topological measures based on surface contact networks appeared to be effective in discriminating sequences native to a specific fold amongst a set of decoys. Conclusions Out of innumerable topological possibilities, only a finite number of specific packing motifs are actually realized in proteins. This small number of motifs could serve as a basis set in the construction of larger networks. Of these, the triplet clique exhibits distinct preference both in terms of composition and geometry. PMID:21605466

2011-01-01

477

Practical hydraulics: a key to efficient drilling  

Microsoft Academic Search

A properly designed hydraulics program that can be modified as dictated by field conditions is essential for attaining optimum drilling efficiency. This article discusses key facets of a hydraulics program and presents a unique nomograph which can be used on the rig to design quickly a simple but effective program. The nomograph, along with an explanation and examples of its

Brouse

1982-01-01

478

Hydraulic Geometry: Empirical Investigations and Theoretical Approaches  

E-print Network

Hydraulic Geometry: Empirical Investigations and Theoretical Approaches B.C. Eatona, a Department geometry equations relate the dimensions of the wetted channel to the stream discharge the channel conveys. One approach to hydraulic geometry considers temporal changes at a single location due to variations

Eaton, Brett

479

On tracking control of cooperative hydraulic manipulators  

Microsoft Academic Search

This paper addresses the problem of tracking control of multiple hydraulic manipulators handling a rigid object. We propose a controller that allows two or more hydraulically-actuated robots cooperatively, to move a rigid object along a desired trajectory while sharing the load and maintaining an acceptable internal force on the object. The parasitic effect of friction in the actuators, as well

H. Zeng; N. Sepehri

2007-01-01

480

Hydraulic Actuator for Ganged Control Rods  

NASA Technical Reports Server (NTRS)

Hydraulic actuator moves several nuclear-reactor control rods in unison. Electromagnetic pump pushes liquid lithium against ends of control rods, forcing them out of or into nuclear reactor. Color arrows show lithium flow for reactor startup and operation. Flow reversed for shutdown. Conceived for use aboard spacecraft, actuator principle applied to terrestrial hydraulic machinery involving motion of ganged rods.

Thompson, D. C.; Robey, R. M.

1986-01-01

481

Hydraulic Permeability of Resorcinol-Formaldehyde Resin  

SciTech Connect

An ion exchange process using spherical resorcinol-formaldehyde (RF) resin is the baseline process for removing cesium from the dissolved salt solution in the high-level waste tanks at the Hanford Site, using large scale columns as part of the Waste Treatment Plant (WTP). The RF resin is also being evaluated for use in the proposed small column ion exchange (SCIX) system, which is an alternative treatment option at Hanford and at the Savannah River Site (SRS). A recirculating test loop with a small ion exchange column was used to measure the effect of oxygen uptake and radiation exposure on the permeability of a packed bed of the RF resin. The lab-scale column was designed to be prototypic of the proposed Hanford columns at the WTP. Although the test equipment was designed to model the Hanford ion exchange columns, the data on changes in the hydraulic permeability of the resin will also be valuable for determining potential pressure drops through the proposed SCIX system. The superficial fluid velocity in the lab-scale test (3.4-5.7 cm/s) was much higher than is planned for the full-scale Hanford columns to generate the maximum pressure drop expected in those columns (9.7 psig). The frictional drag from this high velocity produced forces on the resin in the lab-scale tests that matched the design basis of the full-scale Hanford column. Any changes in the resin caused by the radiation exposure and oxygen uptake were monitored by measuring the pressure drop through the lab-scale column and the physical properties of the resin. Three hydraulic test runs were completed, the first using fresh RF resin at 25 C, the second using irradiated resin at 25 C, and the third using irradiated resin at 45 C. A Hanford AP-101 simulant solution was recirculated through a test column containing 500 mL of Na-form RF resin. Known amounts of oxygen were introduced into the primary recirculation loop by saturating measured volumes of the simulant solution with oxygen and reintroducing the oxygenated simulant into the feed tank. The dissolved oxygen (DO) concentration of the recirculating simulant was monitored, and the amount of oxygen that reacted with the resin was determined from the change in the DO concentration of the recirculating simulant solution. Prior to hydraulic testing the resin for runs 2 and 3 was covered with the simulant solution and irradiated in a spent fuel element at the Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR). Both batches of resin were irradiated to a total gamma dose of 177 Mrad, but the resin for run 2 reached a maximum temperature during irradiation of 51 C, while the resin for run 3 reached a temperature of 38 C. The different temperatures were the result of the operating status of HFIR at the time of the irradiation and were not part of the test plan; however, the results clearly show the impact of the higher-temperature exposure during irradiation. The flow rate and pressure drop data from the test loop runs show that irradiating the RF resin reduces both the void fraction and the permeability of the resin bed. The mechanism for the reduction in permeability is not clear because irradiation increases the particle size of the resin beads and makes them deform less under pressure. Microscopic examination of the resin beads shows that they are all smooth regular spheres and that irradiation or oxygen uptake did not change the shape of the beads. The resin reacts rapidly with DO in the simulant solution, and the reaction with oxygen reduces the permeability of a bed of new resin by about 10% but has less impact on the permeability of irradiated resin. Irradiation increases the toughness of the resin beads, probably by initiating cross-linking reactions in them. Oxygen uptake reduces the crush strength of both new and irradiated resin; however, the pressures that caused the beads to crush are much higher than would be expected during the operation of an ion exchange column. There was no visible evidence of broken beads in any of the resin samples taken from the test loop. Reaction with oxygen red

Taylor, Paul Allen [ORNL

2010-01-01

482

Comparison of Aquifer Recharge Estimates Based on Measured and Estimated Hydraulic Properties  

NASA Astrophysics Data System (ADS)

Because unsaturated hydraulic properties, which are used to estimate recharge, are difficult and time consuming to measure accurately, models that estimate these properties indirectly are often used. Using data from six locations in southern New Jersey that appear to have steady-state flow conditions, five hydraulic property prediction and parameterization techniques were evaluated for recharge estimation. The unsaturated zone at this site, as in many coastal plain regions, is mainly sand to sandy loam in texture, which is considered a highly favorable case for soil hydraulic property estimation. Annual recharge has been estimated for several southern New Jersey watersheds by water budget methods and ranges from 33 to 49 cm/yr. Using these estimates as a gauge of reasonable values for steady flow, several indirect methods were compared to determine which are appropriate for recharge estimation in the coastal plain environment. The methods used in this study were: (1) simple power-law and hand-drawn curve fits to measured unsaturated hydraulic conductivity, (2) measured water retention and measured unsaturated hydraulic conductivity fit using the van Genuchten-Mualem model with fixed and optimized parameter values, (3) unsaturated hydraulic conductivity estimated from measured water retention with fixed and optimized parameter values, (4) estimation of water retention and hydraulic conductivity from bulk density and minimal textural information using the Rosetta pedotransfer function model, and (5) estimation of water retention and hydraulic conductivity using high resolution particle size distributions with the Arya-Paris and van Genuchten-Mualem models. Preliminary results show that while reasonable estimates can come from directly measured unsaturated hydraulic conductivity, the curve fitting method is critical because of the extreme non-linearity of the relationship between hydraulic conductivity and water content. Even a relatively good visual fit can lead to unreasonable recharge estimation values. A hand-drawn interpolation technique, and in some cases a simple power-law fit, yielded better results for these data than the van Genuchten-Mualem curve fit. In all cases, the Rosetta model lead to unreasonably high recharge estimates, primarily due to the over-prediction of saturated hydraulic conductivity. Water retention was predicted relatively well by the Rosetta Model. A combination of the Arya-Paris and van Genuchten-Mualem models also lead to over-prediction of recharge rates, and did not do as well as Rosetta in predicting water retention for this sandy material.

Perkins, K. S.

2003-12-01

483

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

NASA Technical Reports Server (NTRS)

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.

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

1988-01-01

484

Packed fluidized bed blanket for fusion reactor  

DOEpatents

A packed fluidized bed blanket for a fusion reactor providing for efficient radiation absorption for energy recovery, efficient neutron absorption for nuclear transformations, ease of blanket removal, processing and replacement, and on-line fueling/refueling. The blanket of the reactor contains a bed of stationary particles during reactor operation, cooled by a radial flow of coolant. During fueling/refueling, an axial flow is introduced into the bed in stages at various axial locations to fluidize the bed. When desired, the fluidization flow can be used to remove particles from the blanket.

Chi, John W. H. (Mt. Lebanon, PA)

1984-01-01

485

Granular impact and the critical packing state  

NASA Astrophysics Data System (ADS)

Impact dynamics during collisions of spheres with granular media reveal a pronounced and nontrivial dependence on volume fraction ? . Postimpact crater morphology identifies the critical packing state ?cps , where sheared grains neither dilate nor consolidate, and indicates an associated change in spatial response. Current phenomenological models fail to capture the observed impact force for most ? ; only near ?cps is force separable into additive terms linear in depth and quadratic in velocity. At fixed depth the quadratic drag coefficient decreases (increases) with depth for ??cps) . At fixed low velocity, depth dependence of force shows a Janssen-type exponential response with a length scale that decreases with increasing ? and is nearly constant for ?>?cps .

Umbanhowar, Paul; Goldman, Daniel I.

2010-07-01

486

Thermal hydraulics development for CASL  

SciTech Connect

This talk will describe the technical direction of the Thermal-Hydraulics (T-H) Project within the Consortium for Advanced Simulation of Light Water Reactors (CASL) Department of Energy Innovation Hub. CASL is focused on developing a 'virtual reactor', that will simulate the physical processes that occur within a light-water reactor. These simulations will address several challenge problems, defined by laboratory, university, and industrial partners that make up CASL. CASL's T-H efforts are encompassed in two sub-projects: (1) Computational Fluid Dynamics (CFD), (2) Interface Treatment Methods (ITM). The CFD subproject will develop non-proprietary, scalable, verified and validated macroscale CFD simulation tools. These tools typically require closures for their turbulence and boiling models, which will be provided by the ITM sub-project, via experiments and microscale (such as DNS) simulation results. The near-term milestones and longer term plans of these two sub-projects will be discussed.

Lowrie, Robert B [Los Alamos National Laboratory

2010-12-07

487

Hydraulic Geometry and Channel Roughness  

NSDL National Science Digital Library

In this field exercise, students measure channel cross sections in a rough alluvial and smooth bedrock-floored reach in a local stream. This exercise is hypothesis-driven. The hypothesis states that increasing roughness decreases average stream velocity, and so the depth and/or width must increase for the rougher bed. Working in groups, students use hand levels, tape measures, and surveying rods to document channel geometry. They then must reduce the data and plot it as distance-elevation on a chart. Finally, they analyze and compare the results to the predicted roughness-hydraulic geometry relation. Students learn simple surveying methods to collect field data. Students compare real world data to theoretical predictions. Students gain insight into how bank and bed roughness influences water flow, and thus can also influence flood heights. Designed for a geomorphology course Integrates geomorphology into a core course in geology Designed for an introductory geology course Uses geomorphology to solve problems in other fields

Hasbargen, Les

488

Column performance of granular activated carbon packed bed for Pb(II) removal.  

PubMed

The excessive release of lead from lead acid batteries, smelting plant into the environment is a major concern worldwide. Adsorption process is among the most effective techniques for lead removal from wastewater and activated carbon has been widely used as an adsorbent. In this paper an attempt has been made to investigate the adsorption behaviour of Pb(II) from aqueous systems onto granular activated carbon using the batch mode and continuous mode in a packed bed column with more successive service and regeneration. The experiments were performed at constant temperature and dimensions of column and packed bed of granular activated carbon with variation of flows through the bed and concentrations of lead solutions. Breakthrough points were found out for the adsorption of lead on the adsorbent using continuous-flow column operation by varying different operating parameters like hydraulic loading rate from 4 to 16 m(3)/h m(2) and feed concentrates from 20 to 60 mg/l. Granular activated carbon column regeneration using 0.5 M concentration of HNO(3) has been investigated. Results indicate encouraging performance towards removal of Pb(II). PMID:18249492

Dwivedi, Chandra P; Sahu, J N; Mohanty, C R; Mohan, B Raj; Meikap, B C

2008-08-15

489

Continuous phosphorus removal from water by physicochemical method using zero valent iron packed column.  

PubMed

Excessive phosphorus in aquatic systems causes algal bloom resulting in eutrophication. To treat wastewater including effluent of wastewater treatment plant containing various amounts of phosphorus, a series of continuous experiments on removal of phosphorus from water were performed by using an electrochemical method. The spherical type of zero valent iron (ZVI) and silica sand were packed at appropriate volume ratio of 1:2 in a cylindrical column. An electric potential was applied externally, which can be changed as per the operational requirement. The results indicate that optimum hydraulic retention time of 36 min was required to meet the effluent standards with our laboratory-scale experimental setup. Lower amounts of phosphorus were removed by precipitation due to contact with iron, and additional electric potential was not required. In order to remove high amounts of phosphorus (around 150 mg/L as phosphate), external electric potential of 600 V was applied to the reactor. As the precipitation of phosphate mainly occurs at neutral pH, it is likely that FeHPO4 will be the main phosphorus-containing compound. Through the results of the large-scale experiments, the ZVI packed reactor can be used as a filter for removal of phosphorus of less than 10 mg/L as phosphate concentration. PMID:25225938

Jeong, Joo-Young; Ahn, Byoung-Min; Kim, Yu-Jin; Park, Joo-Yang

2014-01-01

490

Model for polygonal hydraulic jumps  

NASA Astrophysics Data System (ADS)

We propose a phenomenological model for the polygonal hydraulic jumps discovered by Ellegaard and co-workers [Nature (London)NATUAS0028-083610.1038/33820 392, 767 (1998); NonlinearityNONLE50951-771510.1088/0951-7715/12/1/001 12, 1 (1999); Physica BPHYBE30921-452610.1016/S0921-4526(96)00373-0 228, 1 (1996)], based on the known flow structure for the type-II hydraulic jumps with a “roller” (separation eddy) near the free surface in the jump region. The model consists of mass conservation and radial force balance between hydrostatic pressure and viscous stresses on the roller surface. In addition, we consider the azimuthal force balance, primarily between pressure and viscosity, but also including nonhydrostatic pressure contributions from surface tension in light of recent observations by Bush and co-workers [J. Fluid Mech.JFLSA70022-112010.1017/S0022112006009839 558, 33 (2006); Phys. Fluids 16, S4 (2004)]. The model can be analyzed by linearization around the circular state, resulting in a parameter relationship for nearly circular polygonal states. A truncated but fully nonlinear version of the model can be solved analytically. This simpler model gives rise to polygonal shapes that are very similar to those observed in experiments, even though surface tension is neglected, and the condition for the existence of a polygon with N corners depends only on a single dimensionless number ?. Finally, we include time-dependent terms in the model and study linear stability of the circular state. Instability occurs for sufficiently small Bond number and the most unstable wavelength is expected to be roughly proportional to the width of the roller as in the Rayleigh-Plateau instability.

Martens, Erik A.; Watanabe, Shinya; Bohr, Tomas

2012-03-01

491

Hydraulic geometry of the Platte River in south-central Nebraska  

USGS Publications Warehouse

At-a-station hydraulic-geometry of the Platte River in south-central Nebraska is complex. The range of exponents of simple power-function relations is large, both between different reaches of the river, and among different sections within a given reach. The at-a-station exponents plot in several fields of the b-f-m diagram, suggesting that morphologic and hydraulic changes with increasing discharge vary considerably. Systematic changes in the plotting positions of the exponents with time indicate that in general, the width exponent has decreased, although trends are not readily apparent in the other exponents. Plots of the hydraulic-geometry relations indicate that simple power functions are not the proper model in all instances. For these sections, breaks in the slopes of the hydraulic geometry relations serve to partition the data sets. Power functions fit separately to the partitioned data described the width-, depth-, and velocity-discharge relations more accurately than did a single power function. Plotting positions of the exponents from hydraulic geometry relations of partitioned data sets on b-f-m diagrams indicate that much of the apparent variations of plotting positions of single power functions results because the single power functions compromise both subsets of partitioned data. For several sections, the shape of the channel primarily accounts for the better fit of two-power functions to partitioned data than a single power function over the entire range of data. These non-log linear relations may have significance for channel maintenance. (USGS)

Eschner, T.R.

1982-01-01

492

Influence of cell packing by centrifugation on 40MHz ultrasound backscatter  

Microsoft Academic Search

High-frequency ultrasound (HFUS) signals backscattered from RBL-2H3 cell pellets prepared under different centrifugal forces were analyzed to investigate the packing effect of cell aggregates. The measurements were performed in a pulse-echo setup with a 40-MHz transducer. The changes of ultrasound signals from cell pellet in backscattered power, statistical parameter, and pellet thickness were monitored after centrifugation at between 100g and

Kweon-Ho Nam; Min Joo Choi; Eun Sook Yoo; Dong-Guk Paeng

2011-01-01

493

Performance characteristics of an electric vehicle lead-acid battery pack at elevated temperatures  

NASA Astrophysics Data System (ADS)

Discharge testing data electric car battery pack over initial electrolyte temperature variations between 27 and 55 C are presented. The tests were conducted under laboratory conditions and then compared to detailed electric vehicle simulation models. Battery discharge capacity increased with temperature for constant current discharges, and battery energy capacity increased with temperature for constant power discharges. Dynamometer tests of the electric test vehicle showed an increase in range of 25% for the higher electrolyte temperature.

Chapman, P.

1982-04-01

494

Mid-sized omnidirectional robot with hydraulic drive and steering  

NASA Astrophysics Data System (ADS)

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.

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

2003-09-01

495

Content-aware photo collage using circle packing.  

PubMed

In this paper, we present a novel approach for automatically creating the photo collage that assembles the interest regions of a given group of images naturally. Previous methods on photo collage are generally built upon a well-defined optimization framework, which computes all the geometric parameters and layer indices for input photos on the given canvas by optimizing a unified objective function. The complex nonlinear form of optimization function limits their scalability and efficiency. From the geometric point of view, we recast the generation of collage as a region partition problem such that each image is displayed in its corresponding region partitioned from the canvas. The core of this is an efficient power-diagram-based circle packing algorithm that arranges a series of circles assigned to input photos compactly in the given canvas. To favor important photos, the circles are associated with image importances determined by an image ranking process. A heuristic search process is developed to ensure that salient information of each photo is displayed in the polygonal area resulting from circle packing. With our new formulation, each factor influencing the state of a photo is optimized in an independent stage, and computation of the optimal states for neighboring photos are completely decoupled. This improves the scalability of collage results and ensures their diversity. We also devise a saliency-based image fusion scheme to generate seamless compositive collage. Our approach can generate the collages on nonrectangular canvases and supports interactive collage that allows the user to refine collage results according to his/her personal preferences. We conduct extensive experiments and show the superiority of our algorithm by comparing against previous methods. PMID:24356362

Yu, Zongqiao; Lu, Lin; Guo, Yanwen; Fan, Rongfei; Liu, Mingming; Wang, Wenping

2014-02-01

496

Optimal packing of a rotating packed bed for H(2)S removal.  

PubMed

The existence of H2S in a system could lead to catalyst deactivation, pipeline corrosion, and environmental pollution. A rotating packed bed (RPB), a novel reactor with high mass transfer efficiency and small dimension, is employed in this study to remove H2S. For RPB, the most significant section for mass transfer is the end-effect zone of packing. A mathematical model for liquid flow in the packing is established to quantify the length of the end-effect zone. A simple and effective visual experimental method is then proposed to investigate the end-effect zone in the RPB. A gas-liquid mass transfer experiment is finally employed to confirm the validity of the proposed mathematical model. With the aid of this model, the length of packing of a RPB used for pilot-scale H2S removal is optimized. The optimized RPB removes 99.8% of H2S (15 vol % to 0.03 vol %) from the system. The proposed model can help optimize the design of a RPB reactor. PMID:24798198

Guo, Kai; Wen, Jiawu; Zhao, Ying; Wang, Yu; Zhang, Zhenzhen; Li, Zongxiang; Qian, Zhi

2014-06-17

497

Howling at two Minnesota wolf pack summer homesites  

USGS Publications Warehouse

Howling sessions were monitored at two Minnesota wolf pack homesites for 2255 h between 29 April and 3 August 1973. All sessions recorded occurred from dusk through early morning, with an evening peak for one pack. Within a night, multiple sessions were grouped temporally, most occurring within an hour of one another. Howling rates for both packs increased throughout the homesite season, with the larger pack howling twice as frequently. The role of howling in both intrapack and interpack contexts was considered. Much of the howling seemed to be involved in the coordination of pack activities. Further, the low frequency and clumped temporal distribution of sessions suggest that howling plays a secondary role in interpack contexts to other modes such as scent marking during the homesite season, but may increase in relative importance once homesites are abandoned and pack travel becomes nomadic.

Harrington, F.H.; Mech, L.D.

1978-01-01

498

Aspects of column fabrication for packed capillary electrochromatography.  

PubMed

Various parameters have been evaluated to develop a process for optimization of column manufacture for packed capillary electrochromatography (CEC). Spherisorb ODS-1 was packed into 75 microm I.D. capillaries to establish a standard set of packing conditions to afford high-performance columns free of voids. Numerous silica-based packing materials including porous and non-porous reversed-phase and ion-exchange phases were employed to evaluate the applicability of the standard conditions. Success of column manufacture and performance demonstrate a relationship to the colligative properties of the packing materials under the applied conditions. Frequently encountered difficulties arising from inadequate column conditioning and void formation in the packed bed are identified and discussed. PMID:10961326

Angus, P D; Demarest, C W; Catalano, T; Stobaugh, J F

2000-07-28

499

Structural characterization of submerged granular packings  

NASA Astrophysics Data System (ADS)

We consider the impact of the effective gravitational acceleration on microstructural properties of granular packings through experimental studies of spherical granular materials saturated within fluids of varying density. We characterize the local organization of spheres in terms of contact connectivity, distribution of the Delaunay free volumes, and the shape factor (parameter of nonsphericity) of the Voronoï polygons. The shape factor gives a clear physical picture of the competition between less and more ordered domains of particles in experimentally obtained packings. As the effective gravity increases, the probability distribution of the shape factor becomes narrower and more localized around the lowest values of the shape factor corresponding to regular hexagon. It is found that curves of the pore distributions are asymmetric with a long tail on the right-hand side, which progressively reduces while the effective gravity gets stronger for lower densities of interstitial fluid. We show that the distribution of local areas (Voronoï cells) broadens with decreasing value of the effective gravity due to the formation of lose structures such as large pores and chainlike structures (arches or bridges). Our results should be particularly helpful in testing the newly developed simulation techniques involving liquid-related forces associated with immersed granular particles.

Jakši?, Z. M.; Š?epanovi?, J. R.; Lon?arevi?, I.; Budinski-Petkovi?, Lj.; Vrhovac, S. B.; Beli?, A.

2014-12-01

500

Understanding shape entropy through local dense packing.  

PubMed

Entropy drives the phase behavior of colloids ranging from dense suspensions of hard spheres or rods to dilute suspensions of hard spheres and depletants. Entropic ordering of anisotropic shapes into complex crystals, liquid crystals, and even quasicrystals was demonstrated recently in computer simulations and experiments. The ordering of shapes appears to arise from the emergence of directional entropic forces (DEFs) that align neighboring particles, but these forces have been neither rigorously defined nor quantified in generic systems. Here, we show quantitatively that shape drives the phase behavior of systems of anisotropic particles upon crowding through DEFs. We define DEFs in generic systems and compute them for several hard particle systems. We show they are on the order of a few times the thermal energy ([Formula: see text]) at the onset of ordering, placing DEFs on par with traditional depletion, van der Waals, and other intrinsic interactions. In experimental systems with these other interactions, we provide direct quantitative evidence that entropic effects of shape also contribute to self-assembly. We use DEFs to draw a distinction between self-assembly and packing behavior. We show that the mechanism that generates directional entropic forces is the maximization of entropy by optimizing local particle packing. We show that this mechanism occurs in a wide class of systems and we treat, in a unified way, the entropy-driven phase behavior of arbitrary shapes, incorporating the well-known works of Kirkwood, Onsager, and Asakura and Oosawa. PMID:25344532

van Anders, Greg; Klotsa, Daphne; Ahmed, N Khalid; Engel, Michael; Glotzer, Sharon C

2014-11-11