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Remote Sensing of Aerosols from Satellites: Why Has It Been Do Difficult to Quantify Aerosol-Cloud Interactions for Climate Assessment, and How Can We Make Progress?

NASA Technical Reports Server (NTRS)

Kahn, Ralph A.

2015-01-01

The organizers of the National Academy of Sciences Arthur M. Sackler Colloquia Series on Improving Our Fundamental Understanding of the Role of Aerosol-Cloud Interactions in the Climate System would like to post Ralph Kahn's presentation entitled Remote Sensing of Aerosols from Satellites: Why has it been so difficult to quantify aerosol-cloud interactions for climate assessment, and how can we make progress? to their public website.

[Actuator placement for active sound and vibration control

NASA Technical Reports Server (NTRS)

1997-01-01

Two refereed journal publications and ten talks given at conferences, seminars, and colloquia resulted from research supported by NASA. They are itemized in this report. The two publications were entitled "Reactive Tabu and Search Sensor Selection in Active Structural Acoustic Control Problems" and "Quelling Cabin Noise in Turboprop Aircraft via Active Control." The conference presentations covered various aspects of actuator placement, including location problems, for active sound and vibration control of cylinders, of commuter jets, of propeller driven or turboprop aircraft, and for quelling aircraft cabin or interior noise.

The International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas

NASA Technical Reports Server (NTRS)

Sugar, J.; Leckrone, D.

1993-01-01

This was the fourth in a series of colloquia begun at the University of Lund, Sweden in 1983 and subsequently held in Toledo, Ohio and Amsterdam, The Netherlands. The purpose of these meetings is to provide an international forum for communication between major users of atomic spectroscopic data and the providers of these data. These data include atomic wavelengths, line shapes, energy levels, lifetimes, and oscillator strengths. Speakers were selected from a wide variety of disciplines including astrophysics, laboratory plasma research, spectrochemistry, and theoretical and experimental atomic physics.

Two Validity Studies of CLEP Subject Examination in Elementary Computer Programming: Fortran IV, U. T. Austin, Spring 1979 and Spring 1982. Research Bulletin 82-8.

ERIC Educational Resources Information Center

Appenzellar, Anne B.; Kelley, H. Paul

Two validity studies of the College Board College-Level Examination Program (CLEP) Subject Examination in Elementary Computer Programming: Fortran IV determined that CLEP scores are appropriate for granting examination credit at the University of Texas at Austin. The standard-setting administration was in the spring of 1979, with a re-evaluation…

Wrap spring clutch syringe ram and frit mixer

DOEpatents

Simpson, Frank B.

2006-07-25

A wrap spring clutch syringe ram pushes at least one syringe with virtually instantaneous starting and stopping, and with constant motion at a defined velocity during the intervening push. The wrap spring clutch syringe ram includes an electric motor, a computer, a flywheel, a wrap spring clutch, a precision lead screw, a slide platform, and syringe reservoirs, a mixing chamber, and a reaction incubation tube. The electric motor drives a flywheel and the wrap spring clutch couples the precision lead screw to the flywheel when a computer enables a solenoid of the wrap spring clutch. The precision lead screw drives a precision slide which causes syringes to supply a portion of solution into the mixing chamber and the incubation tube. The wrap spring clutch syringe ram is designed to enable the quantitative study of solution phase chemical and biochemical reactions, particularly those reactions that occur on the subsecond time scale.

Development of Computer-Based Experiment Set on Simple Harmonic Motion of Mass on Springs

ERIC Educational Resources Information Center

Musik, Panjit

2017-01-01

The development of computer-based experiment set has become necessary in teaching physics in schools so that students can learn from their real experiences. The purpose of this study is to create and to develop the computer-based experiment set on simple harmonic motion of mass on springs for teaching and learning physics. The average period of…

Brownian dynamics simulations with stiff finitely extensible nonlinear elastic-Fraenkel springs as approximations to rods in bead-rod models.

PubMed

Hsieh, Chih-Chen; Jain, Semant; Larson, Ronald G

2006-01-28

A very stiff finitely extensible nonlinear elastic (FENE)-Fraenkel spring is proposed to replace the rigid rod in the bead-rod model. This allows the adoption of a fast predictor-corrector method so that large time steps can be taken in Brownian dynamics (BD) simulations without over- or understretching the stiff springs. In contrast to the simple bead-rod model, BD simulations with beads and FENE-Fraenkel (FF) springs yield a random-walk configuration at equilibrium. We compare the simulation results of the free-draining bead-FF-spring model with those for the bead-rod model in relaxation, start-up of uniaxial extensional, and simple shear flows, and find that both methods generate nearly identical results. The computational cost per time step for a free-draining BD simulation with the proposed bead-FF-spring model is about twice as high as the traditional bead-rod model with the midpoint algorithm of Liu [J. Chem. Phys. 90, 5826 (1989)]. Nevertheless, computations with the bead-FF-spring model are as efficient as those with the bead-rod model in extensional flow because the former allows larger time steps. Moreover, the Brownian contribution to the stress for the bead-FF-spring model is isotropic and therefore simplifies the calculation of the polymer stresses. In addition, hydrodynamic interaction can more easily be incorporated into the bead-FF-spring model than into the bead-rod model since the metric force arising from the non-Cartesian coordinates used in bead-rod simulations is absent from bead-spring simulations. Finally, with our newly developed bead-FF-spring model, existing computer codes for the bead-spring models can trivially be converted to ones for effective bead-rod simulations merely by replacing the usual FENE or Cohen spring law with a FENE-Fraenkel law, and this convertibility provides a very convenient way to perform multiscale BD simulations.

Brownian dynamics simulations with stiff finitely extensible nonlinear elastic-Fraenkel springs as approximations to rods in bead-rod models

NASA Astrophysics Data System (ADS)

Hsieh, Chih-Chen; Jain, Semant; Larson, Ronald G.

2006-01-01

A very stiff finitely extensible nonlinear elastic (FENE)-Fraenkel spring is proposed to replace the rigid rod in the bead-rod model. This allows the adoption of a fast predictor-corrector method so that large time steps can be taken in Brownian dynamics (BD) simulations without over- or understretching the stiff springs. In contrast to the simple bead-rod model, BD simulations with beads and FENE-Fraenkel (FF) springs yield a random-walk configuration at equilibrium. We compare the simulation results of the free-draining bead-FF-spring model with those for the bead-rod model in relaxation, start-up of uniaxial extensional, and simple shear flows, and find that both methods generate nearly identical results. The computational cost per time step for a free-draining BD simulation with the proposed bead-FF-spring model is about twice as high as the traditional bead-rod model with the midpoint algorithm of Liu [J. Chem. Phys. 90, 5826 (1989)]. Nevertheless, computations with the bead-FF-spring model are as efficient as those with the bead-rod model in extensional flow because the former allows larger time steps. Moreover, the Brownian contribution to the stress for the bead-FF-spring model is isotropic and therefore simplifies the calculation of the polymer stresses. In addition, hydrodynamic interaction can more easily be incorporated into the bead-FF-spring model than into the bead-rod model since the metric force arising from the non-Cartesian coordinates used in bead-rod simulations is absent from bead-spring simulations. Finally, with our newly developed bead-FF-spring model, existing computer codes for the bead-spring models can trivially be converted to ones for effective bead-rod simulations merely by replacing the usual FENE or Cohen spring law with a FENE-Fraenkel law, and this convertibility provides a very convenient way to perform multiscale BD simulations.

Spring assisted cranioplasty: A patient specific computational model.

PubMed

Borghi, Alessandro; Rodriguez-Florez, Naiara; Rodgers, Will; James, Gregory; Hayward, Richard; Dunaway, David; Jeelani, Owase; Schievano, Silvia

2018-03-01

Implantation of spring-like distractors in the treatment of sagittal craniosynostosis is a novel technique that has proven functionally and aesthetically effective in correcting skull deformities; however, final shape outcomes remain moderately unpredictable due to an incomplete understanding of the skull-distractor interaction. The aim of this study was to create a patient specific computational model of spring assisted cranioplasty (SAC) that can help predict the individual overall final head shape. Pre-operative computed tomography images of a SAC patient were processed to extract a 3D model of the infant skull anatomy and simulate spring implantation. The distractors were modeled based on mechanical experimental data. Viscoelastic bone properties from the literature were tuned using the specific patient procedural information recorded during surgery and from x-ray measurements at follow-up. The model accurately captured spring expansion on-table (within 9% of the measured values), as well as at first and second follow-ups (within 8% of the measured values). Comparison between immediate post-operative 3D head scanning and numerical results for this patient proved that the model could successfully predict the final overall head shape. This preliminary work showed the potential application of computational modeling to study SAC, to support pre-operative planning and guide novel distractor design. Copyright © 2018 IPEM. Published by Elsevier Ltd. All rights reserved.

EDITORIAL: XVI Brazilian Colloquium on Orbital Dynamics

NASA Astrophysics Data System (ADS)

de Melo, Cristiano F.; Macau, Elbert E. N.; Prado, Antonio B. A.; Hetem Jnr, Annibal

2013-10-01

The XVI Brazilian Colloquium on Orbital Dynamics was held from 26-30 November 2012, at the Biazi Grand Hotel, Serra Negra, São Paulo, Brazil. The Brazilian Colloquia on Orbital Dynamics are scientific events that occur bi-annually and are designed to develop those areas of research in celestial mechanics, orbital dynamics, planetary science, fundamental astronomy, aerospace engineering, and nonlinear systems and chaos. The meeting has been held for 30 years and it brings together researchers, professors and students from South American and also from other continents. Acknowledgements National Council for Scientific and Technological Development - CNPq Coordination for the Improvement of Higher Level - CAPES São Paulo Research Foundation - FAPESP

Vibration computer programs E13101, E13102, E13104, and E13112 and application to the NERVA program. Project 187: Methodology documentation

NASA Technical Reports Server (NTRS)

Mironenko, G.

1972-01-01

Programs for the analyses of the free or forced, undamped vibrations of one or two elastically-coupled lumped parameter teams are presented. Bearing nonlinearities, casing and rotor distributed mass and elasticity, rotor imbalance, forcing functions, gyroscopic moments, rotary inertia, and shear and flexural deformations are all included in the system dynamics analysis. All bearings have nonlinear load displacement characteristics, the solution is achieved by iteration. Rotor imbalances allowed by such considerations as pilot tolerances and runouts as well as bearing clearances (allowing concail or cylindrical whirl) determine the forcing function magnitudes. The computer programs first obtain a solution wherein the bearings are treated as linear springs of given spring rates. Then, based upon the computed bearing reactions, new spring rates are predicted and another solution of the modified system is made. The iteration is continued until the changes to bearing spring rates and bearing reactions become negligibly small.

Graduate Statistics: Student Attitudes

ERIC Educational Resources Information Center

Kennedy, Robert L.; Broadston, Pamela M.

2004-01-01

This study investigated the attitudes toward statistics of graduate students who used a computer program as part of the instruction, which allowed for an individualized, self-paced, student-centered, activity-based course. The twelve sections involved in this study were offered in the spring and fall 2001, spring and fall 2002, spring and fall…

Effect of section shape on frequencies of natural oscillations of tubular springs

NASA Astrophysics Data System (ADS)

Pirogov, S. P.; Chuba, A. Yu; Cherentsov, D. A.

2018-05-01

The necessity of determining the frequencies of natural oscillations of manometric tubular springs is substantiated. Based on the mathematical model and computer program, numerical experiments were performed that allowed us to reveal the effect of geometric parameters on the frequencies of free oscillations of manometric tubular springs.

Biological Approach to System Information Security (BASIS)

DTIC Science & Technology

2003-12-01

Expertise J. Giordano Dr. Popyack AFRL 7 - Computer Engineering, provided by Douglas Summerville, Ph.D., Assistant Professor of the Department of...Skormin, Ph.D., Principal Investigator, Professor, Electrical and Computer Engineering, Binghamton University In addition, Joseph Giordano and Dr...worm was written by Robert Morris in 1988. But the greatest epidemics took place recently: " Melissa " in spring of 1999 and "Love Letter" in spring

How Reflected Wave Fronts Dynamically Establish Hooke's Law in a Spring

ERIC Educational Resources Information Center

Fahy, Stephen; O'Riordan, John; O'Sullivan, Colm; Twomey, Patrick

2012-01-01

A simple benchtop experiment in which a moving cart collides with a fixed spring is described. Force-time and force-distance data recorded during the collision display the transit of compression wave fronts through the spring following impact. These data can be used by students to develop a computational model of the dynamics of this simple…

Progress of projection computed tomography by upgrading of the beamline 37XU of SPring-8

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terada, Yasuko, E-mail: yterada@spring8.or.jp; Suzuki, Yoshio; Uesugi, Kentaro

2016-01-28

Beamline 37XU at SPring-8 has been upgraded for nano-focusing applications. The length of the beamline has been extended to 80 m. By utilizing this length, the beamline has advantages for experiments such as X-ray focusing, X-ray microscopic imaging and X-ray computed tomography. Projection computed tomography measurements were carried out at experimental hutch 3 located 80 m from the light source. CT images of a microcapsule have been successfully obtained with a wide X-ray energy range.

Valve-spring Surge

NASA Technical Reports Server (NTRS)

Marti, Willy

1937-01-01

Test equipment is described that includes a system of three quartz indicators whereby three different pressures could be synchronized and simultaneously recorded on a single oscillogram. This equipment was used to test the reliction of waves at ends of valve spring, the dynamical stress of the valve spring for a single lift of the valve, and measurement of the curve of the cam tested. Other tests included simultaneous recording of the stress at both ends of the spring, spring oscillation during a single lift as a function of speed, computation of amplitude of oscillation for a single lift by harmonic analysis, effect of cam profile, the setting up of resonance, and forced spring oscillation with damping.

Performance on Monitoring Basic Skills Progress--Computation Probes in First, Second, and Third Grade: Is It a Predictor of Pennsylvania System of School Assessment Mathematics Achievement in Third Grade?

ERIC Educational Resources Information Center

Campbell, Adelle C.

2017-01-01

This study examined the predictive relationship of a brief computation measure administered in the fall, winter, and spring of first, second, and third grade with the mathematic portion of a state-mandated academic achievement test administered in the spring of third grade. The relationship between mathematical achievement and resource…

Estimation of evapotranspiration in the Rainbow Springs and Silver Springs basins in North-Central Florida

USGS Publications Warehouse

Knowles, Leel

1996-01-01

Estimates of evapotranspiration (ET) for the Rainbow and Silver Springs ground-water basins in north-central Florida were determined using a regional water-~budget approach and compared to estimates computed using a modified Priestley-Taylor (PT) model calibrated with eddy-correlation data. Eddy-correlation measurements of latent 0~E) and sensible (H) heat flux were made monthly for a few days at a time, and the PT model was used to estimate 3,E between times of measurement during the 1994 water year. A water-budget analysis for the two-basin area indicated that over a 30-year period (196594) annual rainfall was 51.7 inches. Of the annual rainfall, ET accounted for about 37.9 inches; springflow accounted for 13.1 inches; and the remaining 0.7 inch was accounted for by stream-flow, by ground-water withdrawals from the Floridan aquifer system, and by net change in storage. For the same 30-year period, the annual estimate of ET for the Silver Springs basin was 37.6 inches and was 38.5 inches for the Rainbow Springs basin. Wet- and dry-season estimates of ET for each basin averaged between nearly 19 inches and 20 inches, indicating that like rainfall, ET rates during the 4-month wet season were about twice the ET rates during the 8-month dry season. Wet-season estimates of ET for the Rainbow Springs and Silver Springs basins decreased 2.7 inches, and 3.4 inches, respectively, over the 30-year period; whereas, dry-season estimates for the basins decreased about 0.4 inch and1.0 inch, respectively, over the 30-year period. This decrease probably is related to the general decrease in annual rainfall and reduction in net radiation over the basins during the 30-year period. ET rates computed using the modified PT model were compared to rates computed from the water budget for the 1994 water year. Annual ET, computed using the PT model, was 32.0 inches, nearly equal to the ET water-budget estimate of 31.7 inches computed for the Rainbow Springs and Silver Springs basins. Modeled ET rates for 1994 ranged from 14.4 inches per year in January to 51.6 inches per year in May. Water-budget ET rates for 1994 ranged from 12.0 inches per year in March to 61.2 inches per year in July. Potential evapotranspiration rates for 1994 averaged 46.8 inches per year and ranged from 21.6 inches per year in January to 74.4 inches per year in May. Lake evaporation rates averaged 47.1 inches per year and ranged from 18.0 inches per year in January to 72.0 inches per year in May 1994.

Statistical shape modelling to aid surgical planning: associations between surgical parameters and head shapes following spring-assisted cranioplasty.

PubMed

Rodriguez-Florez, Naiara; Bruse, Jan L; Borghi, Alessandro; Vercruysse, Herman; Ong, Juling; James, Greg; Pennec, Xavier; Dunaway, David J; Jeelani, N U Owase; Schievano, Silvia

2017-10-01

Spring-assisted cranioplasty is performed to correct the long and narrow head shape of children with sagittal synostosis. Such corrective surgery involves osteotomies and the placement of spring-like distractors, which gradually expand to widen the skull until removal about 4 months later. Due to its dynamic nature, associations between surgical parameters and post-operative 3D head shape features are difficult to comprehend. The current study aimed at applying population-based statistical shape modelling to gain insight into how the choice of surgical parameters such as craniotomy size and spring positioning affects post-surgical head shape. Twenty consecutive patients with sagittal synostosis who underwent spring-assisted cranioplasty at Great Ormond Street Hospital for Children (London, UK) were prospectively recruited. Using a nonparametric statistical modelling technique based on mathematical currents, a 3D head shape template was computed from surface head scans of sagittal patients after spring removal. Partial least squares (PLS) regression was employed to quantify and visualise trends of localised head shape changes associated with the surgical parameters recorded during spring insertion: anterior-posterior and lateral craniotomy dimensions, anterior spring position and distance between anterior and posterior springs. Bivariate correlations between surgical parameters and corresponding PLS shape vectors demonstrated that anterior-posterior (Pearson's [Formula: see text]) and lateral craniotomy dimensions (Spearman's [Formula: see text]), as well as the position of the anterior spring ([Formula: see text]) and the distance between both springs ([Formula: see text]) on average had significant effects on head shapes at the time of spring removal. Such effects were visualised on 3D models. Population-based analysis of 3D post-operative medical images via computational statistical modelling tools allowed for detection of novel associations between surgical parameters and head shape features achieved following spring-assisted cranioplasty. The techniques described here could be extended to other cranio-maxillofacial procedures in order to assess post-operative outcomes and ultimately facilitate surgical decision making.

Localization Algorithm Based on a Spring Model (LASM) for Large Scale Wireless Sensor Networks.

PubMed

Chen, Wanming; Mei, Tao; Meng, Max Q-H; Liang, Huawei; Liu, Yumei; Li, Yangming; Li, Shuai

2008-03-15

A navigation method for a lunar rover based on large scale wireless sensornetworks is proposed. To obtain high navigation accuracy and large exploration area, highnode localization accuracy and large network scale are required. However, thecomputational and communication complexity and time consumption are greatly increasedwith the increase of the network scales. A localization algorithm based on a spring model(LASM) method is proposed to reduce the computational complexity, while maintainingthe localization accuracy in large scale sensor networks. The algorithm simulates thedynamics of physical spring system to estimate the positions of nodes. The sensor nodesare set as particles with masses and connected with neighbor nodes by virtual springs. Thevirtual springs will force the particles move to the original positions, the node positionscorrespondingly, from the randomly set positions. Therefore, a blind node position can bedetermined from the LASM algorithm by calculating the related forces with the neighbornodes. The computational and communication complexity are O(1) for each node, since thenumber of the neighbor nodes does not increase proportionally with the network scale size.Three patches are proposed to avoid local optimization, kick out bad nodes and deal withnode variation. Simulation results show that the computational and communicationcomplexity are almost constant despite of the increase of the network scale size. The time consumption has also been proven to remain almost constant since the calculation steps arealmost unrelated with the network scale size.

Computational model for noncontact atomic force microscopy: energy dissipation of cantilever.

PubMed

Senda, Yasuhiro; Blomqvist, Janne; Nieminen, Risto M

2016-09-21

We propose a computational model for noncontact atomic force microscopy (AFM) in which the atomic force between the cantilever tip and the surface is calculated using a molecular dynamics method, and the macroscopic motion of the cantilever is modeled by an oscillating spring. The movement of atoms in the tip and surface is connected with the oscillating spring using a recently developed coupling method. In this computational model, the oscillation energy is dissipated, as observed in AFM experiments. We attribute this dissipation to the hysteresis and nonconservative properties of the interatomic force that acts between the atoms in the tip and sample surface. The dissipation rate strongly depends on the parameters used in the computational model.

A New Test Method of Circuit Breaker Spring Telescopic Characteristics Based Image Processing

NASA Astrophysics Data System (ADS)

Huang, Huimin; Wang, Feifeng; Lu, Yufeng; Xia, Xiaofei; Su, Yi

2018-06-01

This paper applied computer vision technology to the fatigue condition monitoring of springs, and a new telescopic characteristics test method is proposed for circuit breaker operating mechanism spring based on image processing technology. High-speed camera is utilized to capture spring movement image sequences when high voltage circuit breaker operated. Then the image-matching method is used to obtain the deformation-time curve and speed-time curve, and the spring expansion and deformation parameters are extracted from it, which will lay a foundation for subsequent spring force analysis and matching state evaluation. After performing simulation tests at the experimental site, this image analyzing method could solve the complex problems of traditional mechanical sensor installation and monitoring online, status assessment of the circuit breaker spring.

A fast mass spring model solver for high-resolution elastic objects

NASA Astrophysics Data System (ADS)

Zheng, Mianlun; Yuan, Zhiyong; Zhu, Weixu; Zhang, Guian

2017-03-01

Real-time simulation of elastic objects is of great importance for computer graphics and virtual reality applications. The fast mass spring model solver can achieve visually realistic simulation in an efficient way. Unfortunately, this method suffers from resolution limitations and lack of mechanical realism for a surface geometry model, which greatly restricts its application. To tackle these problems, in this paper we propose a fast mass spring model solver for high-resolution elastic objects. First, we project the complex surface geometry model into a set of uniform grid cells as cages through *cages mean value coordinate method to reflect its internal structure and mechanics properties. Then, we replace the original Cholesky decomposition method in the fast mass spring model solver with a conjugate gradient method, which can make the fast mass spring model solver more efficient for detailed surface geometry models. Finally, we propose a graphics processing unit accelerated parallel algorithm for the conjugate gradient method. Experimental results show that our method can realize efficient deformation simulation of 3D elastic objects with visual reality and physical fidelity, which has a great potential for applications in computer animation.

Analytical approach on the stiffness of MR fluid filled spring

NASA Astrophysics Data System (ADS)

Sikulskyi, Stanislav; Kim, Daewon

2017-04-01

A solid mechanical spring generally exhibits uniform stiffness. This paper studies a mechanical spring filled with magnetorheological (MR) fluid to achieve controllable stiffness. The hollow spring filled with MR fluid is subjected to a controlled magnetic field in order to change the viscosity of the MR fluid and thereby to change the overall stiffness of the spring. MR fluid is considered as a Bingham viscoplastic linear material in the mathematical model. The goal of this research is to study the feasibility of such spring system by analytically computing the effects of MR fluid on overall spring stiffness. For this purpose, spring mechanics and MR fluid behavior are studied to increase the accuracy of the analysis. Numerical simulations are also performed to generate some assumptions, which simplify calculations in the analytical part. The accuracy of the present approach is validated by comparing the analytical results to previously known experimental results. Overall stiffness variations of the spring are also discussed for different spring designs.

Sources of groundwater and characteristics of surface-water recharge at Bell, White, and Suwannee Springs, Florida, 2012–13

USGS Publications Warehouse

Stamm, John F.; McBride, W. Scott

2016-12-21

Discharge from springs in Florida is sourced from aquifers, such as the Upper Floridan aquifer, which is overlain by an upper confining unit that locally can have properties of an aquifer. Water levels in aquifers are affected by several factors, such as precipitation, recharge, and groundwater withdrawals, which in turn can affect discharge from springs. Therefore, identifying groundwater sources and recharge characteristics can be important in assessing how these factors might affect flows and water levels in springs and can be informative in broader applications such as groundwater modeling. Recharge characteristics include the residence time of water at the surface, apparent age of recharge, and recharge water temperature.The groundwater sources and recharge characteristics of three springs that discharge from the banks of the Suwannee River in northern Florida were assessed for this study: Bell Springs, White Springs, and Suwannee Springs. Sources of groundwater were also assessed for a 150-foot-deep well finished within the Upper Floridan aquifer, hereafter referred to as the UFA well. Water samples were collected for geochemical analyses in November 2012 and October 2013 from the three springs and the UFA well. Samples were analyzed for a suite of major ions, dissolved gases, and isotopes of sulfur, strontium, oxygen, and hydrogen. Daily means of water level and specific conductance at White Springs were continuously recorded from October 2012 through December 2013 by the Suwannee River Water Management District. Suwannee River stage at White Springs was computed on the basis of stage at a U.S. Geological Survey streamgage about 2.4 miles upstream. Water levels in two wells, located about 2.5 miles northwest and 13 miles southeast of White Springs, were also used in the analyses.Major ion concentrations were used to differentiate water from the springs and Upper Floridan aquifer into three groups: Bell Springs, UFA well, and White and Suwannee Springs. When considered together, evidence from water-level, specific conductance, major-ion concentration, and isotope data indicated that groundwater at Bell Springs and the UFA well was a mixture of surface water and groundwater from the upper confining unit, and that groundwater at White and Suwannee Springs was a mixture of surface water, groundwater from the upper confining unit, and groundwater from the Upper Floridan aquifer. Higher concentrations of magnesium in groundwater samples at the UFA well than in samples at Bell Springs might indicate less mixing with surface water at the UFA well than at Bell Springs. Characteristics of surface-water recharge, such as residence time at the surface, apparent age, and recharge water temperature, were estimated on the basis of isotopic ratios, and dissolved concentrations of gases such as argon, tritium, and sulfur hexafluoride. Oxygen and deuterium isotopic ratios were consistent with rapid recharge by rainwater for samples collected in 2012, and longer residence time at the surface (ponding) for samples collected in 2013. Apparent ages of groundwater samples, computed on the basis of tritium activity and sulfur hexafluoride concentration, indicated groundwater recharge occurred after the late 1980s; however, the estimated apparent ages likely represent the average of ages of multiple sources. Recharge since the 1980s is consistent with groundwater from shallow sources, such as the upper confining unit and Upper Floridan aquifer. Recharge water temperature computed for the three springs and UFA well averaged 20.1 degrees Celsius, which is similar to the mean annual air temperature of 20.6 degrees Celsius at a nearby weather station for 1960–2014.

Annual ground-water discharge by evapotranspiration from areas of spring-fed riparian vegetation along the eastern margin of Death Valley, 2000-02

USGS Publications Warehouse

Laczniak, Randell J.; Smith, J. LaRue; DeMeo, Guy A.

2006-01-01

Flow from major springs and seeps along the eastern margin of Death Valley serves as the primary local water supply and sustains much of the unique habitat in Death Valley National Park. Together, these major spring complexes constitute the terminus of the Death Valley Regional Ground-Water Flow System--one of the larger flow systems in the Southwestern United States. The Grapevine Springs complex is the least exploited for water supply and consequently contains the largest area of undisturbed riparian habitat in the park. Because few estimates exist that quantify ground-water discharge from these spring complexes, a study was initiated to better estimate the amount of ground water being discharged annually from these sensitive, spring-fed riparian areas. Results of this study can be used to establish a basis for estimating water rights and as a baseline from which to assess any future changes in ground-water discharge in the park. Evapotranspiration (ET) is estimated volumetrically as the product of ET-unit (general vegetation type) acreage and a representative ET rate. ET-unit acreage is determined from high-resolution multi-spectral imagery; and a representative ET rate is computed from data collected in the Grapevine Springs area using the Bowen-ratio solution to the energy budget, or from rates given in other ET studies in the Death Valley area. The ground-water component of ET is computed by removing the local precipitation component from the ET rate. Two different procedures, a modified soil-adjusted vegetation index using the percent reflectance of the red and near-infrared wavelengths and land-cover classification using multi-spectral imagery were used to delineate the ET units within each major spring-discharge area. On the basis of the more accurate procedure that uses the vegetation index, ET-unit acreage for the Grapevine Springs discharge area totaled about 192 acres--of which 80 acres were moderate-density vegetation and 112 acres were high-density vegetation. ET-unit acreage for two other discharge areas delineated in the Grapevine Springs area (Surprise Springs and Staininger Spring) totaled about 6 and 43 acres, respectively; and for the discharge areas delineated in the Furnace Creek area (Nevares Springs, Cow Creek-Salt Springs, Texas Spring, and Travertine Springs) totaled about 29, 13, 11, and 21 acres, respectively. In discharge areas other than Grapevine Springs, watering and spring diversions have altered the natural distribution of the vegetation. More...

Radii effect on the translation spring constant of force transducer beams

NASA Technical Reports Server (NTRS)

Scott, C. E.

1992-01-01

Multi-component strain-gage force transducer design requires the designer to determine the spring constant of the numerous beams or flexures incorporated in the transducer. The classical beam deflection formulae that are used in calculating these spring constants typically assume that the beam has a uniform moment of inertia along the entire beam length. In practice all beams have a radius at the end where the beam interfaces with the shoulder of the transducer, and on short beams in particular this increases the beam spring constant considerably. A Basic computer program utilizing numerical integration is presented to determine this effect.

Delivering an Informational Hub for Data at the National Center for Computational Toxicology (ACS Spring Meeting) 7 of 7

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) Computational Toxicology Program integrates advances in biology, chemistry, and computer science to help prioritize chemicals for further research based on potential human health risks. This work involves computational and data drive...

8th International Symposium on Quantum Theory and Symmetries (QTS8)

NASA Astrophysics Data System (ADS)

Bijker, Roelof; Krötzsch, Guillermo; Rosas-Ortiz, Óscar; Wolf, Kurt Bernardo

2014-05-01

The Quantum Theory and Symmetries (QTS) international symposia are periodic biannual meetings of the mathematical physics community with special interest in the methods of group theory in their many incarnations, particularly in the symmetries that arise in quantum systems. The QTSs alternate with the International Colloquia on Group Theoretical Methods in Physics since 1999, when Professor Heinz-Dietrich Doebner organized the first one in Goslar, Germany. Subsequent symposia were held in Krakóow, Poland (2001), Cincinnati, USA (2003), Varna, Bulgaria (2005), Valladolid, Spain (2007), Lexington, USA (2009), and Praha, Czech Republic (2011); the eighth QTS was awarded to Mexico (2013), and the next one (2015) will take place in Yerevan, Armenia. Conference photograph Further details, including committees and members, are available in the PDF

Monitoring Springs in the Mojave Desert Using Landsat Time Series Analysis

NASA Technical Reports Server (NTRS)

Potter, Christopher S.

2018-01-01

The purpose of this study, based on Landsat satellite data was to characterize variations and trends over 30 consecutive years (1985-2016) in perennial vegetation green cover at over 400 confirmed Mojave Desert spring locations. These springs were surveyed between in 2015 and 2016 on lands managed in California by the U.S. Bureau of Land Management (BLM) and on several land trusts within the Barstow, Needles, and Ridgecrest BLM Field Offices. The normalized difference vegetation index (NDVI) from July Landsat images was computed at each spring location and a trend model was first fit to the multi-year NDVI time series using least squares linear regression.Â

Hybrid Computation at Louisiana State University.

ERIC Educational Resources Information Center

Corripio, Armando B.

Hybrid computation facilities have been in operation at Louisiana State University since the spring of 1969. In part, they consist of an Electronics Associates, Inc. (EAI) Model 680 analog computer, an EAI Model 693 interface, and a Xerox Data Systems (XDS) Sigma 5 digital computer. The hybrid laboratory is used in a course on hybrid computation…

The EPA CompTox Chemistry Dashboard - an online resource for environmental chemists (ACS Spring Meeting)

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) Computational Toxicology Program integrates advances in biology, chemistry, and computer science to help prioritize chemicals for further research based on potential human health risks. This work involves computational and data drive...

Effect of low-frequency mechanical vibration on orthodontic tooth movement.

PubMed

Yadav, Sumit; Dobie, Thomas; Assefnia, Amir; Gupta, Himank; Kalajzic, Zana; Nanda, Ravindra

2015-09-01

Our objective was to investigate the effect of low-frequency mechanical vibration (LFMV) on the rate of tooth movement, bone volume fraction, tissue density, and the integrity of the periodontal ligament. Our null hypothesis was that there would be no difference in the amount of tooth movement between different values of LFMV. Sixty-four male CD1 mice, 12 weeks old, were used for orthodontic tooth movement. The mice were randomly divided into 2 groups: control groups (baseline; no spring + 5 Hz; no spring + 10 Hz; and no spring + 20 Hz) and experimental groups (spring + no vibration; spring + 5 Hz; spring + 10 Hz; and spring + 20 Hz). In the experimental groups, the first molars were moved mesially for 2 weeks using nickel-titanium coil springs delivering 10 g of force. In the control and experimental groups, LFMV was applied at 5, 10, or 20 Hz. Microfocus x-ray computed tomography analysis was used for tooth movement measurements, bone volume fraction, and tissue density. Additionally, immunostaining for sclerostin, tartrate-resistant acid phosphatase (TRAP) staining, and picrosirius red staining were used on the histologic sections. Simple descriptive statistics were used to summarize the data. Kruskal-Wallis tests were used to compare the outcomes across treatment groups. LFMV did not increase the rate of orthodontic tooth movement. Microfocus x-ray computed tomography analysis showed increases in bone volume fractions and tissue densities with applications of LFMV. Sclerostin expression was decreased with 10 and 20 Hz vibrations in both the control and experimental groups. Additionally, the picrosirius staining showed that LFMV helped in maintaining the thickness and integrity of collagen fibers in the periodontal ligament. There was no significant increase in tooth movement by applying LFMV when compared with the control groups (spring + no vibration). Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Evaluating the Amount of Tooth Movement and Root Resorption during Canine Retraction with Friction versus Frictionless Mechanics Using Cone Beam Computed Tomography

PubMed Central

Makhlouf, Mohamed; Aboul–Ezz, Amr; Fayed, Mona Salah; Hafez, Hend

2018-01-01

BACKGROUND: The current study was carried out to compare the amount of tooth movement during canine retraction comparing two different retraction mechanics; friction mechanics represented by a NiTi closed coil spring versus frictionless mechanics represented by T - loop, and their effect on root resorption using Cone Beam Computed Tomography (CBCT). METHOD: Ten patients were selected in a split-mouth study design that had a malocclusion that necessitates the extraction of maxillary first premolars and retraction of maxillary canines. The right maxillary canines were retracted using T - loops fabricated from 0.017 X 0.025 TMA wires. The left maxillary canines received NiTi coil spring with 150 gm of retraction force. Pre retraction and post retraction Cone Beam Computed Tomography were taken to evaluate the amount of tooth movement and root resorption using three-dimensional planes. RESULTS: T - loop side showed statistically significant higher mean anteroposterior measurement than NiTi coil spring side, indicating a lower amount of canine movement pre and post a canine retraction. Concerning the root resorption, there was no statistically significant change in the mean measurements of canine root length post retraction. CONCLUSION: The NiTi coil spring side showed more distal movement more than the T-loop side. Both retraction mechanics with controlled retraction force, do not cause root resorption. PMID:29531610

Evaluating the Amount of Tooth Movement and Root Resorption during Canine Retraction with Friction versus Frictionless Mechanics Using Cone Beam Computed Tomography.

PubMed

Makhlouf, Mohamed; Aboul-Ezz, Amr; Fayed, Mona Salah; Hafez, Hend

2018-02-15

The current study was carried out to compare the amount of tooth movement during canine retraction comparing two different retraction mechanics; friction mechanics represented by a NiTi closed coil spring versus frictionless mechanics represented by T - loop, and their effect on root resorption using Cone Beam Computed Tomography (CBCT). Ten patients were selected in a split-mouth study design that had a malocclusion that necessitates the extraction of maxillary first premolars and retraction of maxillary canines. The right maxillary canines were retracted using T - loops fabricated from 0.017 X 0.025 TMA wires. The left maxillary canines received NiTi coil spring with 150 gm of retraction force. Pre retraction and post retraction Cone Beam Computed Tomography were taken to evaluate the amount of tooth movement and root resorption using three-dimensional planes. T - loop side showed statistically significant higher mean anteroposterior measurement than NiTi coil spring side, indicating a lower amount of canine movement pre and post a canine retraction. Concerning the root resorption, there was no statistically significant change in the mean measurements of canine root length post retraction. The NiTi coil spring side showed more distal movement more than the T-loop side. Both retraction mechanics with controlled retraction force, do not cause root resorption.

Computer Programs for Library Operations; Results of a Survey Conducted Between Fall 1971 and Spring 1972.

ERIC Educational Resources Information Center

Liberman, Eva; And Others

Many library operations involving large data banks lend themselves readily to computer operation. In setting up library computer programs, in changing or expanding programs, cost in programming and time delays could be substantially reduced if the programmers had access to library computer programs being used by other libraries, providing similar…

Experimental Studies on Dynamic Vibration Absorber using Shape Memory Alloy (NiTi) Springs

NASA Astrophysics Data System (ADS)

Kumar, V. Raj; Kumar, M. B. Bharathi Raj; Kumar, M. Senthil

2011-10-01

Shape memory alloy (SMA) springs have been used as actuators in many applications although their use in the vibration control area is very recent. Since shape memory alloys differ from conventional alloy materials in many ways, the traditional design approach for springs is not completely suitable for designing SMA springs. Some vibration control concepts utilizing unique characteristics of SMA's will be presented in this paper. A dynamic vibration absorber (DVA) using shape memory alloy (SMA) actuator is developed for attenuation of vibration in a cantilever beam. The design procedure of the DVA is presented. The system consists of a cantilever beam which is considered to generate the real-time vibration using shaker. A SMA spring is used with a mass attached to its end. The stiffness of the SMA spring is dynamically varied in such a way to attenuate the vibration. Both simulation and experimentation are carried out using PID controller. The experiments were carried out by interfacing the experimental setup with a computer using LabVIEW software, Data acquisition and control are implemented using a PCI data acquisition card. Standard PID controllers have been used to control the vibration of the beam. Experimental results are used to demonstrate the effectiveness of the controllers designed and the usefulness of the proposed test platform by exciting the structure at resonance. In experimental setup, an accelerometer is used to measure the vibration which is fed to computer and correspondingly the SMA spring is actuated to change its stiffness to control the vibration. The results obtained illustrate that the developed DVA using SMA actuator is very effective in reducing structural response and have great potential to be an active vibration control medium.

Experimental Studies on Dynamic Vibration Absorber using Shape Memory Alloy (NiTi) Springs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumar, V. Raj; Kumar, M. B. Bharathi Raj; Kumar, M. Senthil

2011-10-20

Shape memory alloy (SMA) springs have been used as actuators in many applications although their use in the vibration control area is very recent. Since shape memory alloys differ from conventional alloy materials in many ways, the traditional design approach for springs is not completely suitable for designing SMA springs. Some vibration control concepts utilizing unique characteristics of SMA's will be presented in this paper.A dynamic vibration absorber (DVA) using shape memory alloy (SMA) actuator is developed for attenuation of vibration in a cantilever beam. The design procedure of the DVA is presented. The system consists of a cantilever beammore » which is considered to generate the real-time vibration using shaker. A SMA spring is used with a mass attached to its end. The stiffness of the SMA spring is dynamically varied in such a way to attenuate the vibration. Both simulation and experimentation are carried out using PID controller. The experiments were carried out by interfacing the experimental setup with a computer using LabVIEW software, Data acquisition and control are implemented using a PCI data acquisition card. Standard PID controllers have been used to control the vibration of the beam. Experimental results are used to demonstrate the effectiveness of the controllers designed and the usefulness of the proposed test platform by exciting the structure at resonance. In experimental setup, an accelerometer is used to measure the vibration which is fed to computer and correspondingly the SMA spring is actuated to change its stiffness to control the vibration. The results obtained illustrate that the developed DVA using SMA actuator is very effective in reducing structural response and have great potential to be an active vibration control medium.« less

A Longitudinal Study of Microcomputer Usage at the Community College Level in Kansas, Spring/94.

ERIC Educational Resources Information Center

Leite, Pedro T.

As part of a longitudinal project to inventory computer equipment and identify current instructional use of microcomputers in Kansas community colleges, surveys were sent to the 19 community colleges in Kansas in spring 1994. The surveys solicited data on student enrollment, which subject areas utilized microcomputers, types of hardware available,…

Blinn College Final Grade Distribution Report for Spring 1994 Semester. Student Performance Report. International Research Document No. 012E.

ERIC Educational Resources Information Center

Blinn Coll., Brenham, TX.

Blinn College final course grade distributions are summarized for spring 1990 to 1994 in this four-part report. Section I presents tables of final grade distributions by campus and course in accounting; agriculture; anthropology; biology; business; chemistry; child development; communications; computer science; criminal justice; drama; emergency…

Proceedings of the 3rd World Congress on Integrated Computational Materials Engineering (ICME 2015). Held in Colorado Springs, CO on May 31-June 4, 2015

DTIC Science & Technology

2016-06-28

Springs, Colorado from May 31- June 4, 2015. ONR support in the an1otmt of$15,000 was provided to support the planning , execution , and dissemination of...held in Colorado Springs, Colorado from May 31- June 4, 2015. ONR support in the amount of $15,000 was provided to support the planning , execution ...support to assist TMS in carrying out the various necessary phases of the planning , execution , and result- dissemination efforts of the Congress. In

Campus Computing 1993. The USC National Survey of Desktop Computing in Higher Education.

ERIC Educational Resources Information Center

Green, Kenneth C.; Eastman, Skip

A national survey of desktop computing in higher education was conducted in spring and summer 1993 at over 2500 institutions. Data were responses from public and private research universities, public and private four-year colleges and community colleges. Respondents (N=1011) were individuals specifically responsible for the operation and future…

Outline of the Course in Automated Language Processing.

ERIC Educational Resources Information Center

Pacak, M.; Roberts, A. Hood

The course in computational linguistics described in this paper was given at The American University during the spring semester of 1969. The purpose of the course was "to convey to students with no previous experience an appreciation of the growing art of computational linguistics which encompasses every use to which computers can be put in…

The effects of computer-simulated experiments on high school biology students' problem-solving skills and achievement

NASA Astrophysics Data System (ADS)

Carmack, Gay Lynn Dickinson

2000-10-01

This two-part quasi-experimental repeated measures study examined whether computer simulated experiments have an effect on the problem solving skills of high school biology students in a school-within-a-school magnet program. Specifically, the study identified episodes in a simulation sequence where problem solving skills improved. In the Fall academic semester, experimental group students (n = 30) were exposed to two simulations: CaseIt! and EVOLVE!. Control group students participated in an internet research project and a paper Hardy-Weinberg activity. In the Spring academic semester, experimental group students were exposed to three simulations: Genetics Construction Kit, CaseIt! and EVOLVE! . Spring control group students participated in a Drosophila lab, an internet research project, and Advanced Placement lab 8. Results indicate that the Fall and Spring experimental groups experienced significant gains in scientific problem solving after the second simulation in the sequence. These gains were independent of the simulation sequence or the amount of time spent on the simulations. These gains were significantly greater than control group scores in the Fall. The Spring control group significantly outscored all other study groups on both pretest measures. Even so, the Spring experimental group problem solving performance caught up to the Spring control group performance after the third simulation. There were no significant differences between control and experimental groups on content achievement. Results indicate that CSE is as effective as traditional laboratories in promoting scientific problem solving and that CSE is a useful tool for improving students' scientific problem solving skills. Moreover, retention of problem solving skills is enhanced by utilizing more than one simulation.

Study of the dynamic properties and effects of temperature using a spring model for the bouncing ball

NASA Astrophysics Data System (ADS)

Wadhwa, Ajay

2013-05-01

We studied the motion of a bouncing ball by representing it through an equivalent mass-spring system executing damped harmonic oscillations. We represented the elasticity of the system through the spring constant ‘k’ and the viscous damping effect, causing loss of energy, through damping constant ‘c’. By including these two factors we formed a differential equation for the equivalent mass-spring system of the bouncing ball. This equation was then solved to study the elastic and dynamic properties of its motion by expressing them in terms of experimentally measurable physical quantities such as contact time, coefficient of restitution, etc. We used our analysis for different types of ball material: rubber (lawn-tennis ball, super ball, soccer ball and squash ball) and plastic (table-tennis ball) at room temperature. Since the effect of temperature on the bounce of a squash ball is significant, we studied the temperature dependence of its elastic properties. The experiments were performed using audio and surface-temperature sensors interfaced with a computer through a USB port. The work presented here is suitable for undergraduate laboratories. It particularly emphasizes the use of computer interfacing for conducting conventional physics experiments.

Computer simulation of multigrid body dynamics and control

NASA Technical Reports Server (NTRS)

Swaminadham, M.; Moon, Young I.; Venkayya, V. B.

1990-01-01

The objective is to set up and analyze benchmark problems on multibody dynamics and to verify the predictions of two multibody computer simulation codes. TREETOPS and DISCOS have been used to run three example problems - one degree-of-freedom spring mass dashpot system, an inverted pendulum system, and a triple pendulum. To study the dynamics and control interaction, an inverted planar pendulum with an external body force and a torsional control spring was modeled as a hinge connected two-rigid body system. TREETOPS and DISCOS affected the time history simulation of this problem. System state space variables and their time derivatives from two simulation codes were compared.

A new physical model with multilayer architecture for facial expression animation using dynamic adaptive mesh.

PubMed

Zhang, Yu; Prakash, Edmond C; Sung, Eric

2004-01-01

This paper presents a new physically-based 3D facial model based on anatomical knowledge which provides high fidelity for facial expression animation while optimizing the computation. Our facial model has a multilayer biomechanical structure, incorporating a physically-based approximation to facial skin tissue, a set of anatomically-motivated facial muscle actuators, and underlying skull structure. In contrast to existing mass-spring-damper (MSD) facial models, our dynamic skin model uses the nonlinear springs to directly simulate the nonlinear visco-elastic behavior of soft tissue and a new kind of edge repulsion spring is developed to prevent collapse of the skin model. Different types of muscle models have been developed to simulate distribution of the muscle force applied on the skin due to muscle contraction. The presence of the skull advantageously constrain the skin movements, resulting in more accurate facial deformation and also guides the interactive placement of facial muscles. The governing dynamics are computed using a local semi-implicit ODE solver. In the dynamic simulation, an adaptive refinement automatically adapts the local resolution at which potential inaccuracies are detected depending on local deformation. The method, in effect, ensures the required speedup by concentrating computational time only where needed while ensuring realistic behavior within a predefined error threshold. This mechanism allows more pleasing animation results to be produced at a reduced computational cost.

Implant preloading in extension reduces spring length change in dynamic intraligamentary stabilization: a biomechanical study on passive kinematics of the knee.

PubMed

Häberli, Janosch; Voumard, Benjamin; Kösters, Clemens; Delfosse, Daniel; Henle, Philipp; Eggli, Stefan; Zysset, Philippe

2018-06-01

Dynamic intraligamentary stabilization (DIS) is a primary repair technique for acute anterior cruciate ligament (ACL) tears. For internal bracing of the sutured ACL, a metal spring with 8 mm maximum length change is preloaded with 60-80 N and fixed to a high-strength polyethylene braid. The bulky tibial hardware results in bone loss and may cause local discomfort with the necessity of hardware removal. The technique has been previously investigated biomechanically; however, the amount of spring shortening during movement of the knee joint is unknown. Spring shortening is a crucial measure, because it defines the necessary dimensions of the spring and, therefore, the overall size of the implant. Seven Thiel-fixated human cadaveric knee joints were subjected to passive range of motion (flexion/extension, internal/external rotation in 90° flexion, and varus/valgus stress in 0° and 20° flexion) and stability tests (Lachman/KT-1000 testing in 0°, 15°, 30°, 60°, and 90° flexion) in the ACL-intact, ACL-transected, and DIS-repaired state. Kinematic data of femur, tibia, and implant spring were recorded with an optical measurement system (Optotrak) and the positions of the bone tunnels were assessed by computed tomography. Length change of bone tunnel distance as a surrogate for spring shortening was then computed from kinematic data. Tunnel positioning in a circular zone with r = 5 mm was simulated to account for surgical precision and its influence on length change was assessed. Over all range of motion and stability tests, spring shortening was highest (5.0 ± 0.2 mm) during varus stress in 0° knee flexion. During flexion/extension, spring shortening was always highest in full extension (3.8 ± 0.3 mm) for all specimens and all simulations of bone tunnels. Tunnel distance shortening was highest (0.15 mm/°) for posterior femoral and posterior tibial tunnel positioning and lowest (0.03 mm/°) for anterior femoral and anterior tibial tunnel positioning. During passive flexion/extension, the highest spring shortening was consistently measured in full extension with a continuous decrease towards flexion. If preloading of the spring is performed in extension, the spring can be downsized to incorporate a maximum length change of 5 mm resulting in a smaller implant with less bone sacrifice and, therefore, improved conditions in case of revision surgery.

Comparison of a degree-day computer and a recording thermograph in a forest environment.

Treesearch

Boyd E. Wickman

1985-01-01

A field test showed that degree-days accumulated by a miniature computer and a recording thermograph in early spring and summer were comparable. For phenological studies the biophenometer was as accurate and more efficient than the hygrothermograph.

Campus Computing 1990: The EDUCOM/USC Survey of Desktop Computing in Higher Education.

ERIC Educational Resources Information Center

Green, Kenneth C.; Eastman, Skip

The National Survey of Desktop Computer Use in Higher Education was conducted in the spring and summer of 1990 by the Center for Scholarly Technology at the University of Southern California, in cooperation with EDUCOM and with support from 15 corporate sponsors. The survey was designed to collect information about campus planning, policies, and…

THE EFFECTS OF MAINTENANCE ACTIONS ON THE PFDavg OF SPRING OPERATED PRESSURE RELIEF VALVES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harris, S.; Gross, R.

2014-04-01

The safety integrity level (SIL) of equipment used in safety instrumented functions is determined by the average probability of failure on demand (PFDavg) computed at the time of periodic inspection and maintenance, i.e., the time of proof testing. The computation of PFDavg is generally based solely on predictions or estimates of the assumed constant failure rate of the equipment. However, PFDavg is also affected by maintenance actions (or lack thereof) taken by the end user. This paper shows how maintenance actions can affect the PFDavg of spring operated pressure relief valves (SOPRV) and how these maintenance actions may be accountedmore » for in the computation of the PFDavg metric. The method provides a means for quantifying the effects of changes in maintenance practices and shows how these changes impact plant safety.« less

The Effects of Maintenance Actions on the PFDavg of Spring Operated Pressure Relief Valves

DOE PAGES

Harris, S.; Gross, R.; Goble, W; ...

2015-12-01

The safety integrity level (SIL) of equipment used in safety instrumented functions is determined by the average probability of failure on demand (PFDavg) computed at the time of periodic inspection and maintenance, i.e., the time of proof testing. The computation of PFDavg is generally based solely on predictions or estimates of the assumed constant failure rate of the equipment. However, PFDavg is also affected by maintenance actions (or lack thereof) taken by the end user. This paper shows how maintenance actions can affect the PFDavg of spring operated pressure relief valves (SOPRV) and how these maintenance actions may be accountedmore » for in the computation of the PFDavg metric. The method provides a means for quantifying the effects of changes in maintenance practices and shows how these changes impact plant safety.« less

MESO-Adaptation Based on Model Oriented Reengineering Process for Human-Computer Interface (MESOMORPH)

DTIC Science & Technology

2004-02-01

Publishing Company , Addison- Wesley Systems Programming Series, 1990. [5] E. Stroulia and T. Systa. Dynamic analysis for reverse engineering and program...understanding, Applied Computing Reviews, Spring 2002, ACM Press. [6] El- Ramly , Mohammad; Stroulia, Eleni; Sorenson, Paul. “Recovering software

Development of an extended Kalman filter for the self-sensing application of a spring-biased shape memory alloy wire actuator

NASA Astrophysics Data System (ADS)

Gurung, H.; Banerjee, A.

2016-02-01

This report presents the development of an extended Kalman filter (EKF) to harness the self-sensing capability of a shape memory alloy (SMA) wire, actuating a linear spring. The stress and temperature of the SMA wire, constituting the state of the system, are estimated using the EKF, from the measured change in electrical resistance (ER) of the SMA. The estimated stress is used to compute the change in length of the spring, eliminating the need for a displacement sensor. The system model used in the EKF comprises the heat balance equation and the constitutive relation of the SMA wire coupled with the force-displacement behavior of a spring. Both explicit and implicit approaches are adopted to evaluate the system model at each time-update step of the EKF. Next, in the measurement-update step, estimated states are updated based on the measured electrical resistance. It has been observed that for the same time step, the implicit approach consumes less computational time than the explicit method. To verify the implementation, EKF estimated states of the system are compared with those of an established model for different inputs to the SMA wire. An experimental setup is developed to measure the actual spring displacement and ER of the SMA, for any time-varying voltage applied to it. The process noise covariance is decided using a heuristic approach, whereas the measurement noise covariance is obtained experimentally. Finally, the EKF is used to estimate the spring displacement for a given input and the corresponding experimentally obtained ER of the SMA. The qualitative agreement between the EKF estimated displacement with that obtained experimentally reveals the true potential of this approach to harness the self-sensing capability of the SMA.

Hydraulic actuator mechanism to control aircraft spoiler movements through dual input commands

NASA Technical Reports Server (NTRS)

Irick, S. C. (Inventor)

1981-01-01

An aircraft flight spoiler control mechanism is described. The invention enables the conventional, primary spoiler control system to retain its operational characteristics while accommodating a secondary input controlled by a conventional computer system to supplement the settings made by the primary input. This is achieved by interposing springs between the primary input and the spoiler control unit. The springs are selected to have a stiffness intermediate to the greater force applied by the primary control linkage and the lesser resistance offered by the spoiler control unit. Thus, operation of the primary input causes the control unit to yield before the springs, yet, operation of the secondary input, acting directly on the control unit, causes the springs to yield and absorb adjustments before they are transmitted into the primary control system.

Velocity and bottom-stress measurements in the bottom boundary layer, outer Norton Sound, Alaska.

USGS Publications Warehouse

Cacchione, D.A.; Drake, D.E.; Wiberg, P.

1982-01-01

We have used long-term measurements of near-bottom velocities at four heights above the sea floor in Norton Sound, Alaska, to compute hourly values of shear velocity u., roughness and bottom-drag coefficient. Maximum sediment resuspension and transport, predicted for periods when the computed value of u. exceeds a critical level, occur during peak tidal currents associated with spring tides. The fortnightly variation in u. is correlated with a distinct nepheloid layer that intensifies and thickens during spring tides and diminishes and thins during neap tides. The passage of a storm near the end of the experiment caused significantly higher u. values than those found during fair weather.-from Authros

Fatigue Life Assessment of 65Si7 Leaf Springs: A Comparative Study

PubMed Central

Arora, Vinkel Kumar; Bhushan, Gian; Aggarwal, M. L.

2014-01-01

The experimental fatigue life prediction of leaf springs is a time consuming process. The engineers working in the field of leaf springs always face a challenge to formulate alternate methods of fatigue life assessment. The work presented in this paper provides alternate methods for fatigue life assessment of leaf springs. A 65Si7 light commercial vehicle leaf spring is chosen for this study. The experimental fatigue life and load rate are determined on a full scale leaf spring testing machine. Four alternate methods of fatigue life assessment have been depicted. Firstly by SAE spring design manual approach the fatigue test stroke is established and by the intersection of maximum and initial stress the fatigue life is predicted. The second method constitutes a graphical method based on modified Goodman's criteria. In the third method codes are written in FORTRAN for fatigue life assessment based on analytical technique. The fourth method consists of computer aided engineering tools. The CAD model of the leaf spring has been prepared in solid works and analyzed using ANSYS. Using CAE tools, ideal type of contact and meshing elements have been proposed. The method which provides fatigue life closer to experimental value and consumes less time is suggested. PMID:27379327

Examining the Computer Self-Efficacy Perceptions of Gifted Students

ERIC Educational Resources Information Center

Kaplan, Abdullah; Öztürk, Mesut; Doruk, Muhammet; Yilmaz, Alper

2013-01-01

This study was conducted in order to determine the computer self-efficacy perceptions of gifted students. The research group of this study is composed of gifted students (N = 36) who were studying at the Science and Arts Center in Gümüshane province in the spring semester of the 2012-2013 academic year. The "Computer Self-Efficacy Perception…

The interview with a patient on dialysis: feeling, emotions and fears.

PubMed

Brunori, Francesco; Dozio, Beatrice; Colzani, Sara; Pozzi, Marco; Pisano, Lucia; Galassi, Andrea; Santorelli, Gennaro; Auricchio, Sara; Busnelli, Luisa; Di Carlo, Angela; Viganò, Monica; Calabrese, Valentina; Mariani, Laura; Mossa, Monica; Longoni, Stefania; Scanziani, Renzo

2016-01-01

This study has been performed in the Nephrology and Dialysis Unit, in Desio Hospital, Italy. The aim of this study is to evaluate, starting from research questions, which information is given to patient in the pre-dialysis colloquia for his/her chosen dialysis methods. Moreover, the study evaluated feelings, emotions and fears since the announcement of the necessity of dialysis treatment. The objective of the study was reached through the interview with patients on dialysis. The fact-finding survey was based on the tools of social research, as the semi-structured interview. Instead of using the questionnaire, even though it make it easier to collect larger set of data, the Authors decided to interview patients in person, since the interview allows direct patient contact and to build a relationship of trust with the interviewer, in order to allow patient explain better his/her feeling.

DOD HPC Insights. Spring 2012

DTIC Science & Technology

2012-04-01

spr2012-Final.indd 1 5/9/2012 10:54:32 AM DOD Spring 2012 INSIGHTS A publication of the Department of Defense High Performance Computing...0188 Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing...collection of information if it does not display a currently valid OMB control number. 1 . REPORT DATE 2012 2. REPORT TYPE 3. DATES COVERED 4. TITLE

Rapid Quantification of Energy Absorption and Dissipation Metrics for PPE Padding Materials

DTIC Science & Technology

2010-01-22

dampers ,   i.e.,  Hooke’s  Law  springs  and   viscous ...absorbing/dissipating materials. Input forces caused by blast pressures, determined from computational fluid dynamics (CFD) analysis and simulation...simple  lumped-­‐ parameter  elements   –  spring,  k  (energy  storage)   –  damper ,  b  (energy  dissipa/on   Rapid

Forest fire weather and computed fire occurrence in western Oregon and western Washington in 1960.

Treesearch

Owen P. Cramer

1960-01-01

Fire season severity in 1960 was about average in western Washington but was very high in western Oregon. Severity of the entire season in both States was slightly greater than in 1959. Although spring was less severe, both summer and fall were slightly more severe than comparable parts of the previous fire season. Spring fire danger in western Washington was as low as...

Representative Sampling: Follow-up of Spring 1972 and Spring 1973 Students. TEX-SIS FOLLOW-UP SC3.

ERIC Educational Resources Information Center

Wilkinson, Larry; And Others

This report presents the findings of a research study, conducted by the College of the Mainland (COM) as a subcontractor for Project FOLLOW-UP, designed to test the accuracy of random sampling and to measure non-response bias in mail surveys. In 1975, a computer-generated random sample of 500 students was drawn from a population of 1,256 students…

Computer Modeling of Complete IC Fabrication Process.

DTIC Science & Technology

1984-01-01

Venson Shaw 10. C. S. Chang 11. Elizabeth Batson 12. Richard Pinto 13. Jacques Beauduoin SPEAKERS: 1. Tayo Akinwande 2. Dimitri Antoniadis 3. Walter...Numerical Model of Polysilicon Emitter Contacts in Bipolar Transistors,’ To be published IEEE Trans. Electron Devices. [34] M. R. Pinto , R. W. Dutton...Received PhD, Spring 1082) Balaji Swaminathan (Received PhD, Spring 1983) Len Mei Research Associate Michael Kump Research Assistant Mark Pinto Research

Deployment Analysis of a Simple Tape-Spring Hinge Using Probabilistic Methods

NASA Technical Reports Server (NTRS)

Lyle, Karen H.; Horta, Lucas G.

2012-01-01

Acceptance of new deployable structures architectures and concepts requires validated design methods to minimize the expense involved with technology validation flight testing. Deployable concepts for large lightweight spacecraft include booms, antennae, and masts. This paper explores the implementation of probabilistic methods in the design process for the deployment of a strain-energy mechanism, specifically a simple tape-spring hinge. Strain-energy mechanisms are attractive for deployment in very lightweight systems because they do not require the added mass and complexity associated with motors and controllers. However, designers are hesitant to include free deployment, strain-energy mechanisms because of the potential for uncontrolled behavior. In the example presented here, the tapespring cross-sectional dimensions have been varied and a target displacement during deployment has been selected as the design metric. Specifically, the tape-spring should reach the final position in the shortest time with the minimal amount of overshoot and oscillations. Surrogate models have been used to reduce computational expense. Parameter values to achieve the target response have been computed and used to demonstrate the approach. Based on these results, the application of probabilistic methods for design of a tape-spring hinge has shown promise as a means of designing strain-energy components for more complex space concepts.

Education Technology Survey, 1995.

ERIC Educational Resources Information Center

Quality Education Data, Inc., Denver, CO.

Primary research (in-depth telephone interviews) was conducted among elementary and secondary school educators in Spring 1995 to determine usage, attitudes, and barriers to usage for five electronic in-school services: Cable in the Classroom; computers, laserdisc or CD-ROM; Internet; online computer services such as America Online and Prodigy; and…

A seasonal forecast scheme for the Inner Mongolia spring drought part-II: a logical reasoning evidence-based method for spring predictions

NASA Astrophysics Data System (ADS)

Gao, Tao; Wulan, Wulan; Yu, Xiao; Yang, Zelong; Gao, Jing; Hua, Weiqi; Yang, Peng; Si, Yaobing

2018-05-01

Spring precipitation is the predominant factor that controls meteorological drought in Inner Mongolia (IM), China. This study used the anomaly percentage of spring precipitation (PAP) as a drought index to measure spring drought. A scheme for forecasting seasonal drought was designed based on evidence of spring drought occurrence and speculative reasoning methods introduced in computer artificial intelligence theory. Forecast signals with sufficient lead-time for predictions of spring drought were extracted from eight crucial areas of oceans and 500-hPa geopotential height. Using standardized values, these signals were synthesized into three examples of spring drought evidence (SDE) depending on their primary effects on three major atmospheric circulation components of spring precipitation in IM: the western Pacific subtropical high, North Polar vortex, and East Asian trough. Thresholds for the SDE were determined following numerical analyses of the influential factors. Furthermore, five logical reasoning rules for distinguishing the occurrence of SDE were designed after examining all possible combined cases. The degree of confidence in the rules was determined based on estimations of their prior probabilities. Then, an optimized logical reasoning scheme was identified for judging the possibility of spring drought. The scheme was successful in hindcast predictions of 11 of the 16 (accuracy: 68.8%) spring droughts that have occurred during 1960-2009. Moreover, the accuracy ratio for the same period was 82.0% for drought (PAP ≤ -20%) or not (PAP > -20%). Predictions for the recent 6-year period (2010-2015) demonstrated successful outcomes.

New geothermal database for Utah

USGS Publications Warehouse

Blackett, Robert E.; ,

1993-01-01

The Utah Geological Survey complied a preliminary database consisting of over 800 records on thermal wells and springs in Utah with temperatures of 20??C or greater. Each record consists of 35 fields, including location of the well or spring, temperature, depth, flow-rate, and chemical analyses of water samples. Developed for applications on personal computers, the database will be useful for geochemical, statistical, and other geothermal related studies. A preliminary map of thermal wells and springs in Utah, which accompanies the database, could eventually incorporate heat-flow information, bottom-hole temperatures from oil and gas wells, traces of Quaternary faults, and locations of young volcanic centers.

Compilation of historical water-quality data for selected springs in Texas, by ecoregion

USGS Publications Warehouse

Heitmuller, Franklin T.; Williams, Iona P.

2006-01-01

Springs are important hydrologic features in Texas. A database of about 2,000 historically documented springs and available spring-flow measurements previously has been compiled and published, but water-quality data remain scattered in published sources. This report by the U.S. Geological Survey, in cooperation with the Texas Parks and Wildlife Department, documents the compilation of data for 232 springs in Texas on the basis of a set of criteria and the development of a water-quality database for the selected springs. The selection of springs for compilation of historical water-quality data in Texas was made using existing digital and hard-copy data, responses to mailed surveys, selection criteria established by various stakeholders, geographic information systems, and digital database queries. Most springs were selected by computing the highest mean spring flows for each Texas level III ecoregion. A brief assessment of the water-quality data for springs in Texas shows that few data are available in the Arizona/New Mexico Mountains, High Plains, East Central Texas Plains, Western Gulf Coastal Plain, and South Central Plains ecoregions. Water-quality data are more abundant for the Chihuahuan Deserts, Edwards Plateau, and Texas Blackland Prairies ecoregions. Selected constituent concentrations in Texas springs, including silica, calcium, magnesium, sodium, potassium, strontium, sulfate, chloride, fluoride, nitrate (nitrogen), dissolved solids, and hardness (as calcium carbonate) are comparatively high in the Chihuahuan Deserts, Southwestern Tablelands, Central Great Plains, and Cross Timbers ecoregions, mostly as a result of subsurface geology. Comparatively low concentrations of selected constituents in Texas springs are associated with the Arizona/New Mexico Mountains, Southern Texas Plains, East Central Texas Plains, and South Central Plains ecoregions.

Text-mining strategies to support computational research in chemical toxicity (ACS 2017 Spring meeting)

EPA Science Inventory

With 26 million citations, PubMed is one of the largest sources of information about the activity of chemicals in biological systems. Because this information is expressed in natural language and not stored as data, using the biomedical literature directly in computational resear...

E-Assessment Adaptation at a Military Vocational College: Student Perceptions

ERIC Educational Resources Information Center

Cigdem, Harun; Oncu, Semiral

2015-01-01

This survey study examines an assessment methodology through e-quizzes administered at a military vocational college and subsequent student perceptions in spring 2013 at the "Computer Networks" course. A total of 30 Computer Technologies and 261 Electronic and Communication Technologies students took three e-quizzes. Data were gathered…

Methods Used in a Recent Computer Selection Study.

ERIC Educational Resources Information Center

Botten, LeRoy H.

A study was conducted at Andrews University, Berrien Springs, Michigan to determine selection of a computer for both academic and administrative purposes. The university has a total enrollment of 2,100 students and includes a college, graduate school and seminary. An initial feasibility study delineated criteria and desirable components of the…

Effect of keyswitch design of desktop and notebook keyboards related to key stiffness and typing force.

PubMed

Bufton, Marcia J; Marklin, Richard W; Nagurka, Mark L; Simoneau, Guy G

2006-08-15

This study aimed to compare and analyse rubber-dome desktop, spring-column desktop and notebook keyboards in terms of key stiffness and fingertip typing force. The spring-column keyboard resulted in the highest mean peak contact force (0.86N), followed by the rubber dome desktop (0.68N) and the notebook (0.59N). All these differences were statistically significant. Likewise, the spring-column keyboard registered the highest fingertip typing force and the notebook keyboard the lowest. A comparison of forces showed the notebook (rubber dome) keyboard had the highest fingertip-to-peak contact force ratio (overstrike force), and the spring-column generated the least excess force (as a ratio of peak contact force). The results of this study could aid in optimizing computer key design that could possibly reduce subject discomfort and fatigue.

Educational Technology and the Restructuring Movement: Lessons from Research on Computers in Classrooms.

ERIC Educational Resources Information Center

Kell, Diane; And Others

This paper presents findings from a recently completed study of the use of computers in primary classrooms as one source of evidence concerning the role technology can play in school restructuring efforts. The sites for the study were selected by Apple Computer, Inc. in the spring of 1988 and included 43 classrooms in 10 schools in 6 large, mostly…

Working Ni-Mn-Ga Single Crystals in a Magnetic Field Against a Spring Load

NASA Astrophysics Data System (ADS)

Lindquist, P. G.; Müllner, P.

2015-03-01

This research characterizes ferromagnetic shape memory elements for use as mechanical actuators. A single crystal of Ni-Mn-Ga was pre-strained in compression from 0 to 6 % and then the shape was recovered with a magnetic field perpendicular to the loading direction while working against a pair of springs. The magnetic field was raised from 0 to 0.64 MA/m and then reduced to zero field. Eight pairs of springs with combined spring constants ranging from 14.3 to 269.4 N/mm were used. When the magnetic field was on, the sample expanded against the springs due to magnetic field-induced strain. When the magnetic field was turned off, the springs compressed the sample back to the initial size before the next cycle. During each cycle, force and displacement were measured and the specific work was computed. Specific work increased with the applied magnetic field and the pre-strain, with a maximum of 14 kJ/m3 at 4.5 % pre-strain and 0.64 MA/m. This value is five times less than the values suggested in the literature which were inferred from stress-strain curves measured under various magnetic fields. The spring prescribes the load-displacement path of the magnetic shape memory element and controls the work output of the actuator.

Implementing a Computer/Technology Endorsement in a Classroom Technology Master's Program.

ERIC Educational Resources Information Center

Brownell, Gregg; O'Bannon, Blanche; Brownell, Nancy

In the spring of 1998, the Master's program in Classroom Technology at Bowling Green State University (Ohio) was granted conditional approval to grant, as part of the program, the new State of Ohio Department of Education computer/technology endorsement. This paper briefly describes Ohio's change from certification to licensure, the removal of…

A "Service-Learning Approach" to Teaching Computer Graphics

ERIC Educational Resources Information Center

Hutzel, Karen

2007-01-01

The author taught a computer graphics course through a service-learning framework to undergraduate and graduate students in the spring of 2003 at Florida State University (FSU). The students in this course participated in learning a software program along with youths from a neighboring, low-income, primarily African-American community. Together,…

Implementing Content Review for Communication and Computation Prerequisites. Adopted Spring 2011

ERIC Educational Resources Information Center

Academic Senate for California Community Colleges, 2011

2011-01-01

This paper is one of a collection of papers written by the Academic Senate for California Community Colleges (ASCCC) to support the use of content review as the basis for establishing communication and computation prerequisites. "Student Success: The Case for Establishing Prerequisites Through Content Review" was adopted at the Fall 2010…

Twenty Five Years in Cheminformatics - A Career Path Through a Diverse Series of Roles and Responsibilities (INVITED TALK) (ACS Spring meeting)

EPA Science Inventory

Antony Williams is a Computational Chemist at the US Environmental Protection Agency in the National Center for Computational Toxicology. He has been involved in cheminformatics and the dissemination of chemical information for over twenty-five years. He has worked for a Fortune ...

Origin and characteristics of discharge at San Marcos Springs based on hydrologic and geochemical data (2008-10), Bexar, Comal, and Hays Counties, Texas

USGS Publications Warehouse

Musgrove, MaryLynn; Crow, Cassi L.

2012-01-01

The Edwards aquifer in south-central Texas is a productive and important water resource. Several large springs issuing from the aquifer are major discharge points, popular locations for recreational activities, and habitat for threatened and endangered species. Discharges from Comal and San Marcos Springs, the first and second largest spring complexes in Texas, are used as thresholds in groundwater management strategies for the Edwards aquifer. Comal Springs is generally understood to be supplied by predominantly regional groundwater flow paths; the hydrologic connection of San Marcos Springs with the regional flow system, however, is less understood. During November 2008–December 2010, a hydrologic and geochemical investigation of San Marcos Springs was conducted by the U.S. Geological Survey (USGS) in cooperation with the San Antonio Water System. The primary objective of this study was to define and characterize sources of discharge from San Marcos Springs. During this study, hydrologic conditions transitioned from exceptional drought (the dry period, November 1, 2008 to September 8, 2009) to wetter than normal (the wet period, September 9, 2009 to December 31, 2010), which provided the opportunity to investigate the hydrogeology of San Marcos Springs under a wide range of hydrologic conditions. Water samples were collected from streams, groundwater wells, and springs at and in the vicinity of San Marcos Springs, including periodic (routine) sampling (every 3–7 weeks) and sampling in response to storms. Samples were analyzed for major ions, trace elements, nutrients, and selected stable and radiogenic isotopes (deuterium, oxygen, carbon, strontium). Additionally, selected physicochemical properties were measured continuously at several sites, and hydrologic data were compiled from other USGS efforts (stream and spring discharge). Potential aquifer recharge was evaluated from local streams, and daily recharge or gain/loss estimates were computed for several local streams. Local rainfall and recharge events were compared with physicochemical properties and geochemical variability at San Marcos Springs, with little evidence for dilution by local recharge.

"Computers: Cure-All or Snake Oil?" Proceedings from the Spring Meeting of the Nebraska Library Association, College and University Section (Bellevue, Nebraska, April 20, 1984).

ERIC Educational Resources Information Center

Krzywkowski, Valerie I., Ed.

The 15 papers in this collection discuss various aspects of computer use in libraries and several other aspects of library service not directly related to computers. Following an introduction and a list of officers, the papers are: (1) "Criminal Justice and Related Databases" (Kate E. Adams); (2) "Software and Hard Thought:…

Increasing productivity of the McAuto CAD/CAE system by user-specific applications programming

NASA Technical Reports Server (NTRS)

Plotrowski, S. M.; Vu, T. H.

1985-01-01

Significant improvements in the productivity of the McAuto Computer-Aided Design/Computer-Aided Engineering (CAD/CAE) system were achieved by applications programming using the system's own Graphics Interactive Programming language (GRIP) and the interface capabilities with the main computer on which the system resides. The GRIP programs for creating springs, bar charts, finite element model representations and aiding management planning are presented as examples.

Nonlinear Phononic Periodic Structures and Granular Crystals

DTIC Science & Technology

2012-02-10

nonlinear mass-spring lattices by E. Fermi, J. Pasta , and S. Ulam in 1955 [27], there has been a wealth of interest in the dynamics of nonlinear...lattices. Using one of the first modern computers, Fermi, Pasta , and Ulam (FPU) studied a system where the restoring (spring) force between two adjacent...graphene ribbons. Applied Physics Letters, 2009. 95(3). 27. M. Porter, N.Z., B. Hu, and D. Campell, Fermi, Pasta , Ulam and the birth of experimental

Hydrologic and geochemical monitoring in Long Valley Caldera, Mono County, California, 1985

USGS Publications Warehouse

Farrar, C.D.; Sorey, M.L.; Rojstaczer, S.A.; Janik, C.J.; Winnett, T.L.; Clark, M.D.

1987-01-01

Hydrologic and geochemical monitoring, to detect changes caused by magmatic and tectonic processes in the Long Valley caldera has continued through 1985. The monitoring included the collection of the following types of data: chemical and isotopic composition of water and gases from springs, wells, and steam vents; temperatures in wells, springs, and steam vents; flow rates of springs and streams; water levels in wells; and barometric pressure and precipitation at several sites. In addition, reservoir temperatures for the geothermal system were estimated from computations based on chemical geothermometers applied to fluid samples from wells and springs. Estimates of thermal water discharged from springs were made on the basis of boron and chloride fluxes in surface waters for selected sites in the Casa Diablo area and along the Mammoth-Hot Creek drainage. These data are presented in tables and graphs. The Long Valley area was relatively quiescent throughout 1985 in terms of geodetic changes and seismic activity. As a consequence , the hydrologic system varied mainly in response to seasonal influences of temperature, atmospheric pressure, and precipitation. However, spring flows near Casa Diablo were influenced by pumping at the geothermal production well field nearby. (Author 's abstract)

Vibration of a string against multiple spring-mass-damper stoppers

NASA Astrophysics Data System (ADS)

Shin, Ji-Hwan; Talib, Ezdiani; Kwak, Moon K.

2018-02-01

When a building sways due to strong wind or an earthquake, the elevator rope can undergo resonance, resulting in collision with the hoist-way wall. In this study, a hard stopper and a soft stopper comprised of a spring-mass-damper system installed along the hoist-way wall were considered to prevent the string from undergoing excessive vibrations. The collision of the string with multiple hard stoppers and multiple spring-mass-damper stoppers was investigated using an analytical method. The result revealed new formulas and computational algorithms that are suitable for simulating the vibration of the string against multiple stoppers. The numerical results show that the spring-mass-damper stopper is more effective in suppressing the vibrations of the string and reducing structural failure. The proposed algorithms were shown to be efficient to simulate the motion of the string against a vibration stopper.

Statistical Mechanics Model of Solids with Defects

NASA Astrophysics Data System (ADS)

Kaufman, M.; Walters, P. A.; Ferrante, J.

1997-03-01

Previously(M.Kaufman, J.Ferrante,NASA Tech. Memor.,1996), we examined the phase diagram for the failure of a solid under isotropic expansion and compression as a function of stress and temperature with the "springs" modelled by the universal binding energy relation (UBER)(J.H.Rose, J.R.Smith, F.Guinea, J.Ferrante, Phys.Rev.B29, 2963 (1984)). In the previous calculation we assumed that the "springs" failed independently and that the strain is uniform. In the present work, we have extended this statistical model of mechanical failure by allowing for correlations between "springs" and for thermal fluctuations in strains. The springs are now modelled in the harmonic approximation with a failure threshold energy E0, as an intermediate step in future studies to reinclude the full non-linear dependence of the UBER for modelling the interactions. We use the Migdal-Kadanoff renormalization-group method to determine the phase diagram of the model and to compute the free energy.

Implementation of the glacial rebound prestress advection correction in general-purpose finite element analysis software: Springs versus foundations

NASA Astrophysics Data System (ADS)

Schmidt, Peter; Lund, Björn; Hieronymus, Christoph

2012-03-01

When general-purpose finite element analysis software is used to model glacial isostatic adjustment (GIA), the first-order effect of prestress advection has to be accounted for by the user. We show here that the common use of elastic foundations at boundaries between materials of different densities will produce incorrect displacements, unless the boundary is perpendicular to the direction of gravity. This is due to the foundations always acting perpendicular to the surface to which they are attached, while the body force they represent always acts in the direction of gravity. If prestress advection is instead accounted for by the use of elastic spring elements in the direction of gravity, the representation will be correct. The use of springs adds a computation of the spring constants to the analysis. The spring constant for a particular node is defined by the product of the density contrast at the boundary, the gravitational acceleration, and the area supported by the node. To be consistent with the finite element formulation, the area is evaluated by integration of the nodal shape functions. We outline an algorithm for the calculation and include a Python script that integrates the shape functions over a bilinear quadrilateral element. For linear rectangular and triangular elements, the area supported by each node is equal to the element area divided the number of defining nodes, thereby simplifying the computation. This is, however, not true in the general nonrectangular case, and we demonstrate this with a simple 1-element model. The spring constant calculation is simple and performed in the preprocessing stage of the analysis. The time spent on the calculation is more than compensated for by a shorter analysis time, compared to that for a model with foundations. We illustrate the effects of using springs versus foundations with a simple two-dimensional GIA model of glacial loading, where the Earth model has an inclined boundary between the overlying elastic layer and the lower viscoelastic layer. Our example shows that the error introduced by the use of foundations is large enough to affect an analysis based on high-accuracy geodetic data.

Changes in running kinematics, kinetics, and spring-mass behavior over a 24-h run.

PubMed

Morin, Jean-Benoît; Samozino, Pierre; Millet, Guillaume Y

2011-05-01

This study investigated the changes in running mechanics and spring-mass behavior over a 24-h treadmill run (24TR). Kinematics, kinetics, and spring-mass characteristics of the running step were assessed in 10 experienced ultralong-distance runners before, every 2 h, and after a 24TR using an instrumented treadmill dynamometer. These measurements were performed at 10 km·h, and mechanical parameters were sampled at 1000 Hz for 10 consecutive steps. Contact and aerial times were determined from ground reaction force (GRF) signals and used to compute step frequency. Maximal GRF, loading rate, downward displacement of the center of mass, and leg length change during the support phase were determined and used to compute both vertical and leg stiffness. Subjects' running pattern and spring-mass behavior significantly changed over the 24TR with a 4.9% higher step frequency on average (because of a significantly 4.5% shorter contact time), a lower maximal GRF (by 4.4% on average), a 13.0% lower leg length change during contact, and an increase in both leg and vertical stiffness (+9.9% and +8.6% on average, respectively). Most of these changes were significant from the early phase of the 24TR (fourth to sixth hour of running) and could be speculated as contributing to an overall limitation of the potentially harmful consequences of such a long-duration run on subjects' musculoskeletal system. During a 24TR, the changes in running mechanics and spring-mass behavior show a clear shift toward a higher oscillating frequency and stiffness, along with lower GRF and leg length change (hence a reduced overall eccentric load) during the support phase of running. © 2011 by the American College of Sports Medicine

The Polish Collection at the Alliance College Library in Cambridge Springs, PA: The Origins of the Collection in 1950, Its Rapid Development in the 1970's and the Introduction of the Online Computer Library Center (OCLC) in 1982.

ERIC Educational Resources Information Center

Kozaczka, Stanley J.

This essay outlines the development, present condition, and future direction of the 20,000-volume Polish research collection at Alliance College, located in Cambridge Springs, Pennsylvania. Alliance College was founded in 1912 by the Polish National Alliance (PNA), a life insurance fraternal organization. In 1931 its entire library collection was…

EarthSat spring wheat yield system test 1975, appendix 4

NASA Technical Reports Server (NTRS)

1976-01-01

A computer system is presented which processes meteorological data from both ground observations and meteorologic satellites to define plant weather aspects on a four time per day basis. Plant growth stages are calculated and soil moisture profiles are defined by the system. The EarthSat system assesses plant stress and prepares forecasts of end-of-year yields. The system was used to forecast spring wheat yields in the upper Great Plains states. Hardware and software documentation is provided.

Spring, 1980, DECUS symposium review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, M.J.; Duffy, J.M.; McDonald, W.M.

1980-10-24

The Digital Equipment Computer Users Society (DECUS) holds biannual symposia where its membership and the host company can exchange ideas, problems, and solutions. This report by the newly formed DECUS Local User Group at LLL collects information gathered at the Spring '80 symposium in Chicago on April 22-25. Information is presented for the following special interest groups (SIGs): RSX/IAS SIG, VAX/VSM SIG, PASCAL (languages) SIG, networks SIG, TECO SIG, LSI-11 SIG, RT-11 SIG, site manager SIG, and database SIG. (RWR)

Teachers' Computer Self-Efficacy and Their Use of Educational Technology

ERIC Educational Resources Information Center

Turel, Vehbi

2014-01-01

This study examined the use of educational technology by primary and subject teachers (i.e. secondary and high school teachers) in a small town in the eastern part of Turkey in the spring of 2012. The study examined the primary, secondary and high school teachers': (1) personal and computer related (demographic) characteristics; (2) their computer…

Survey of Computer Facilities in Minnesota and North Dakota.

ERIC Educational Resources Information Center

MacGregor, Donald

In order to attain a better understanding of the data processing manpower needs of business and industry, a survey instrument was designed and mailed to 570 known and possible computer installations in the Minnesota/North Dakota area. The survey was conducted during the spring of 1975, and concentrated on the kinds of equipment and computer…

Constructivist-Compatible Beliefs and Practices among U.S. Teachers. Teaching, Learning, and Computing: 1998 National Survey Report #4.

ERIC Educational Resources Information Center

Ravitz, Jason L.; Becker, Henry Jay; Wong, YanTien

This report, the forth in a series from the spring 1998 national survey, "Teaching, Learning, and Computing," examines teachers' survey responses that describe the frequency with which their teaching practice involves those five types of activities and the frequency with which their practice involves more traditional transmission and…

The Predictive Validity of a Computer-Adaptive Assessment of Kindergarten and First-Grade Reading Skills

ERIC Educational Resources Information Center

Clemens, Nathan H.; Hagan-Burke, Shanna; Luo, Wen; Cerda, Carissa; Blakely, Alane; Frosch, Jennifer; Gamez-Patience, Brenda; Jones, Meredith

2015-01-01

This study examined the predictive validity of a computer-adaptive assessment for measuring kindergarten reading skills using the STAR Early Literacy (SEL) test. The findings showed that the results of SEL assessments administered during the fall, winter, and spring of kindergarten were moderate and statistically significant predictors of year-end…

The Challenges of Improving the Teaching-Learning Process in Computer Studies.

ERIC Educational Resources Information Center

Siegel, Michael Eric

In spring 1984, a study was conducted at the University of Maryland's University College to evaluate the effectiveness of computer studies faculty. The student ratings of these faculty members were compared with the ratings given to mathematics faculty and to all other faculty teaching that term. On all three evaluation criteria (i.e., encourages…

Introducing Computational Thinking to Young Learners: Practicing Computational Perspectives through Embodiment in Mathematics Education

ERIC Educational Resources Information Center

Sung, Woonhee; Ahn, Junghyun; Black, John B.

2017-01-01

A science, technology, engineering, and mathematics-influenced classroom requires learning activities that provide hands-on experiences with technological tools to encourage problem-solving skills (Brophy et al. in "J Eng Educ" 97(3):369-387, 2008; Mataric et al. in "AAAI spring symposium on robots and robot venues: resources for AI…

Microcomputer Usage at the Community College Level in the State of Kansas.

ERIC Educational Resources Information Center

Leite, Pedro T.

In spring 1992, a study was performed to identify the current use of microcomputers for instruction at community colleges in Kansas. A questionnaire was sent to 20 community colleges, requesting information on subject areas in which computers are used in instruction, types and quantities of computers used, types of operating systems used, use of…

Arithmetical Computation: Competence after Three Years of Learning under Differing Instructional Programs.

ERIC Educational Resources Information Center

Brownell, William A.; And Others

Reported are the results and conclusions of an arithmetic investigation made in the schools of Scotland in the spring and fall of 1966. The first problem in this investigation was to ascertain which, if either, of two unlike programs of instruction was more effective in developing skill in computation. The second was to determine the value of an…

An Evaluation of the Computer Science 11E Course Offered During the Spring Semester of 1973.

ERIC Educational Resources Information Center

Durward, M. Lynne; Ellis, E. N.

The evaluation of Computer Science 11E, a locally-developed course offered in six Vancouver secondary schools, consisted of four parts: a questionnaire to teachers concerning all aspects of their courses, as well as their own evaluation of the program, a questionnaire to students designed to determine their attitude toward the course and what they…

Examining the Difference in Student Achievement between Face-to-Face and Online Computer Classes

ERIC Educational Resources Information Center

Hearn, Phillips Turner

2017-01-01

The purpose of this study was to compare the achievement of students taking a computer applications class in one of two instructional methods, traditional face-to-face and online, at a Southeastern community college. The research questions examined more than 3,000 samples from the summer of 2012 through the spring semester of 2016. There were…

Gamma Ray Astronomy

NASA Technical Reports Server (NTRS)

Wu, S. T.

2000-01-01

The project has progressed successfully during this period of performance. The highlights of the Gamma Ray Astronomy teams efforts are: (1) Support daily BATSE data operations, including receipt, archival and dissemination of data, quick-look science analysis, rapid gamma-ray burst and transient monitoring and response efforts, instrument state-of-health monitoring, and instrument commanding and configuration; (2) On-going scientific analysis, including production and maintenance of gamma-ray burst, pulsed source and occultation source catalogs, gamma-ray burst spectroscopy, studies of the properties of pulsars and black holes, and long-term monitoring of hard x-ray sources; (3) Maintenance and continuous improvement of BATSE instrument response and calibration data bases; (4) Investigation of the use of solid state detectors for eventual application and instrument to perform all sky monitoring of X-Ray and Gamma sources with high sensitivity; and (5) Support of BATSE outreach activities, including seminars, colloquia and World Wide Web pages. The highlights of this efforts can be summarized in the publications and presentation list.

A visiting scientist program for the burst and transient source experiment

NASA Technical Reports Server (NTRS)

Kerr, Frank J.

1995-01-01

During this project, Universities Space Research Association provided program management and the administration for overseeing the performance of the total contractual effort. The program director and administrative staff provided the expertise and experience needed to efficiently manage the program.USRA provided a program coordinator and v visiting scientists to perform scientific research with Burst and Transient Source Experiment (BATSE) data. This research was associated with the primary scientific objectives of BATSE and with the various BATSE collaborations which were formed in response to the Compton Gamma Ray Observatory Guest Investigator Program. USRA provided administration for workshops, colloquia, the preparation of scientific documentation, etc. and also provided flexible program support in order to meet the on-going needs of MSFC's BATSE program. USRA performed tasks associated with the recovery, archiving, and processing of scientific data from BATSE. A bibliography of research in the astrophysics discipline is attached as Appendix 1. Visiting Scientists and Research Associates performed activities on this project, and their technical reports are attached as Appendix 2.

Attenuation of empennage buffet response through active control of damping using piezoelectric material

NASA Technical Reports Server (NTRS)

Heeg, Jennifer; Miller, Jonathan M.; Doggett, Robert V., Jr.

1993-01-01

Dynamic response and damping data obtained from buffet studies conducted in a low-speed wind tunnel by using a simple, rigid model attached to spring supports are presented. The two parallel leaf spring supports provided a means for the model to respond in a vertical translation mode, thus simulating response in an elastic first bending mode. Wake-induced buffeting flow was created by placing an airfoil upstream of the model of that the wake of the airfoil impinged on the model. Model response was sensed by a strain gage mounted on one of the springs. The output signal from the strain gage was fed back through a control law implemented on a desktop computer. The processed signals were used to 'actuate' a piezoelectric bending actuator bonded to the other spring in such a way as to add damping as the model responded. The results of this 'proof-of-concept' study show that the piezoelectric actuator was effective in attenuating the wake-induced buffet response over the range of parameters investigated.

Low frequency driven electromagnetic energy harvester for self-powered system

NASA Astrophysics Data System (ADS)

Lee, Byung-Chul; Ataur Rahman, Md; Hyun, Seung-Ho; Chung, Gwiy-Sang

2012-12-01

This paper describes a low frequency driven electromagnetic energy harvester (EMEH) for a self-powered system. The EMEH consists of two thin flame resistant (FR-4) springs, NdFeB permanent magnets, and a copper coil. The FR-4 spring was fabricated by a desk computer numerical control (CNC) 3D modeling machine. The two FR-4 springs were used at the top and bottom sides of the device to reduce the stress on the springs and to achieve linear movement of the moving magnet. The finite element method (FEM) is used to investigate the mechanical properties of the system. The proposed EMEH can generate up to 1.52 mW at a resonance frequency of 16 Hz with an acceleration of 0.2 g (g = 9.8 m s-2) and a superior normalized power density (NPD) of 1.07 mW cm-3 g2. The EMEH attached to the engine of an automobile produced 2.4 mW of power, showing the viability of practical applications.

Location estimation in wireless sensor networks using spring-relaxation technique.

PubMed

Zhang, Qing; Foh, Chuan Heng; Seet, Boon-Chong; Fong, A C M

2010-01-01

Accurate and low-cost autonomous self-localization is a critical requirement of various applications of a large-scale distributed wireless sensor network (WSN). Due to its massive deployment of sensors, explicit measurements based on specialized localization hardware such as the Global Positioning System (GPS) is not practical. In this paper, we propose a low-cost WSN localization solution. Our design uses received signal strength indicators for ranging, light weight distributed algorithms based on the spring-relaxation technique for location computation, and the cooperative approach to achieve certain location estimation accuracy with a low number of nodes with known locations. We provide analysis to show the suitability of the spring-relaxation technique for WSN localization with cooperative approach, and perform simulation experiments to illustrate its accuracy in localization.

Principal facts for a gravity survey of the Double Hot Springs Known Geothermal Resource Area, Humboldt County, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterson, D.L.; Kaufmann, H.E.

1978-01-01

During July 1977, forty-nine gravity stations were obtained in the Double Hot Springs Known Geothermal Resource Area and vicinity, northwestern Nevada. The gravity observations were made with a Worden gravimeter having a scale factor of about 0.5 milligal per division. No terrain corrections have been applied to these data. The earth tide correction was not used in drift reduction. The Geodetic Reference System 1967 formula (International Association of Geodesy, 1967) was used to compute theoretical gravity.

The DZERO Level 3 Data Acquisition System

NASA Astrophysics Data System (ADS)

Angstadt, R.; Brooijmans, G.; Chapin, D.; Clements, M.; Cutts, D.; Haas, A.; Hauser, R.; Johnson, M.; Kulyavtsev, A.; Mattingly, S. E. K.; Mulders, M.; Padley, P.; Petravick, D.; Rechenmacher, R.; Snyder, S.; Watts, G.

2004-06-01

The DZERO experiment began RunII datataking operation at Fermilab in spring 2001. The physics program of the experiment requires the Level 3 data acquisition (DAQ) system system to handle average event sizes of 250 kilobytes at a rate of 1 kHz. The system routes and transfers event fragments of approximately 1-20 kilobytes from 63 VME crate sources to any of approximately 100 processing nodes. It is built upon a Cisco 6509 Ethernet switch, standard PCs, and commodity VME single board computers (SBCs). The system has been in full operation since spring 2002.

The energy of naturally curved elastic rods with an application to the stretching and contraction of a free helical spring as a model for DNA

NASA Astrophysics Data System (ADS)

Manning, Gerald S.

2015-09-01

We give a contemporary and direct derivation of a classical, but insufficiently familiar, result in the theory of linear elasticity—a representation for the energy of a stressed elastic rod with central axis that intrinsically takes the shape of a general space curve. We show that the geometric torsion of the space curve, while playing a crucial role in the bending energy, is physically unrelated to the elastic twist. We prove that the twist energy vanishes in the lowest-energy states of a rod subject to constraints that do not restrict the twist. The stretching and contraction energies of a free helical spring are computed. There are local high-energy minima. We show the possibility of using the spring to model the chirality of DNA. We then compare our results with an available atomic level energy simulation that was performed on DNA unconstrained in the same sense as the free spring. We find some possible reflections of springlike behavior in the mechanics of DNA, but, unsurprisingly, the base pairs lend a material substance to the core of DNA that a spring does not capture.

The energy of naturally curved elastic rods with an application to the stretching and contraction of a free helical spring as a model for DNA.

PubMed

Manning, Gerald S

2015-09-14

We give a contemporary and direct derivation of a classical, but insufficiently familiar, result in the theory of linear elasticity-a representation for the energy of a stressed elastic rod with central axis that intrinsically takes the shape of a general space curve. We show that the geometric torsion of the space curve, while playing a crucial role in the bending energy, is physically unrelated to the elastic twist. We prove that the twist energy vanishes in the lowest-energy states of a rod subject to constraints that do not restrict the twist. The stretching and contraction energies of a free helical spring are computed. There are local high-energy minima. We show the possibility of using the spring to model the chirality of DNA. We then compare our results with an available atomic level energy simulation that was performed on DNA unconstrained in the same sense as the free spring. We find some possible reflections of springlike behavior in the mechanics of DNA, but, unsurprisingly, the base pairs lend a material substance to the core of DNA that a spring does not capture.

Cubical Mass-Spring Model design based on a tensile deformation test and nonlinear material model.

PubMed

San-Vicente, Gaizka; Aguinaga, Iker; Tomás Celigüeta, Juan

2012-02-01

Mass-Spring Models (MSMs) are used to simulate the mechanical behavior of deformable bodies such as soft tissues in medical applications. Although they are fast to compute, they lack accuracy and their design remains still a great challenge. The major difficulties in building realistic MSMs lie on the spring stiffness estimation and the topology identification. In this work, the mechanical behavior of MSMs under tensile loads is analyzed before studying the spring stiffness estimation. In particular, the performed qualitative and quantitative analysis of the behavior of cubical MSMs shows that they have a nonlinear response similar to hyperelastic material models. According to this behavior, a new method for spring stiffness estimation valid for linear and nonlinear material models is proposed. This method adjusts the stress-strain and compressibility curves to a given reference behavior. The accuracy of the MSMs designed with this method is tested taking as reference some soft-tissue simulations based on nonlinear Finite Element Method (FEM). The obtained results show that MSMs can be designed to realistically model the behavior of hyperelastic materials such as soft tissues and can become an interesting alternative to other approaches such as nonlinear FEM.

The energy of naturally curved elastic rods with an application to the stretching and contraction of a free helical spring as a model for DNA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manning, Gerald S., E-mail: jerrymanning@rcn.com

We give a contemporary and direct derivation of a classical, but insufficiently familiar, result in the theory of linear elasticity—a representation for the energy of a stressed elastic rod with central axis that intrinsically takes the shape of a general space curve. We show that the geometric torsion of the space curve, while playing a crucial role in the bending energy, is physically unrelated to the elastic twist. We prove that the twist energy vanishes in the lowest-energy states of a rod subject to constraints that do not restrict the twist. The stretching and contraction energies of a free helicalmore » spring are computed. There are local high-energy minima. We show the possibility of using the spring to model the chirality of DNA. We then compare our results with an available atomic level energy simulation that was performed on DNA unconstrained in the same sense as the free spring. We find some possible reflections of springlike behavior in the mechanics of DNA, but, unsurprisingly, the base pairs lend a material substance to the core of DNA that a spring does not capture.« less

About Maggie's Place.

ERIC Educational Resources Information Center

Emmens, Carol E.

1982-01-01

Describes "Maggie's Place," the library computer system of the Pikes Peak Library District, Colorado Springs, Colorado, noting its use as an electronic card catalog and community information file, accessibility by home users and library users, and terminal considerations. (EJS)

Hydroclimate of the Spring Mountains and Sheep Range, Clark County, Nevada

USGS Publications Warehouse

Moreo, Michael T.; Senay, Gabriel B.; Flint, Alan L.; Damar, Nancy A.; Laczniak, Randell J.; Hurja, James

2014-01-01

Precipitation, potential evapotranspiration, and actual evapotranspiration often are used to characterize the hydroclimate of a region. Quantification of these parameters in mountainous terrains is difficult because limited access often hampers the collection of representative ground data. To fulfill a need to characterize ecological zones in the Spring Mountains and Sheep Range of southern Nevada, spatially and temporally explicit estimates of these hydroclimatic parameters are determined from remote-sensing and model-based methodologies. Parameter-elevation Regressions on Independent Slopes Model (PRISM) precipitation estimates for this area ranges from about 100 millimeters (mm) in the low elevations of the study area (700 meters [m]) to more than 700 mm in the high elevations of the Spring Mountains (> 2,800 m). The PRISM model underestimates precipitation by 7–15 percent based on a comparison with four high‑elevation precipitation gages having more than 20 years of record. Precipitation at 3,000-m elevation is 50 percent greater in the Spring Mountains than in the Sheep Range. The lesser amount of precipitation in the Sheep Range is attributed to partial moisture depletion by the Spring Mountains of eastward-moving, cool-season (October–April) storms. Cool-season storms account for 66–76 percent of annual precipitation. Potential evapotranspiration estimates by the Basin Characterization Model range from about 700 mm in the high elevations of the Spring Mountains to 1,600 mm in the low elevations of the study area. The model realistically simulates lower potential evapotranspiration on northeast-to-northwest facing slopes compared to adjacent southeast-to-southwest facing slopes. Actual evapotranspiration, estimated using a Moderate Resolution Imaging Spectroradiometer based water-balance model, ranges from about 100 to 600 mm. The magnitude and spatial variation of simulated, actual evapotranspiration was validated by comparison to PRISM precipitation. Estimated groundwater recharge, computed as the residual of precipitation depleted by actual evapotranspiration, is within the range of previous estimates. A climatic water deficit dataset and aridity-index-based climate zones are derived from precipitation and evapotranspiration datasets. Climate zones range from arid in the lower elevations of the study area to humid in small pockets on north- to northeast-facing slopes in the high elevations of the Spring Mountains. Correlative analyses between hydroclimatic variables and mean ecosystem elevations indicate that the climatic water deficit is the best predictor of ecosystem distribution (R2 = 0.92). Computed water balances indicate that substantially more recharge is generated in the Spring Mountains than in the Sheep Range. A geospatial database containing compiled and developed hydroclimatic data and other pertinent information accompanies this report.

Use of the negative binomial-truncated Poisson distribution in thunderstorm prediction

NASA Technical Reports Server (NTRS)

Cohen, A. C.

1971-01-01

A probability model is presented for the distribution of thunderstorms over a small area given that thunderstorm events (1 or more thunderstorms) are occurring over a larger area. The model incorporates the negative binomial and truncated Poisson distributions. Probability tables for Cape Kennedy for spring, summer, and fall months and seasons are presented. The computer program used to compute these probabilities is appended.

32 CFR 536.30 - Action upon receipt of claim.

Code of Federal Regulations, 2014 CFR

2014-07-01

... in any other format, shall be scanned into a computer and uploaded onto the TSCA database so that it... Medicine, Armed Forces Institute of Pathology, 1335 E. West Highway, #6-100, Silver Spring, MD 20910-6254...

32 CFR 536.30 - Action upon receipt of claim.

Code of Federal Regulations, 2012 CFR

2012-07-01

... in any other format, shall be scanned into a computer and uploaded onto the TSCA database so that it... Medicine, Armed Forces Institute of Pathology, 1335 E. West Highway, #6-100, Silver Spring, MD 20910-6254...

32 CFR 536.30 - Action upon receipt of claim.

Code of Federal Regulations, 2011 CFR

2011-07-01

... in any other format, shall be scanned into a computer and uploaded onto the TSCA database so that it... Medicine, Armed Forces Institute of Pathology, 1335 E. West Highway, #6-100, Silver Spring, MD 20910-6254...

32 CFR 536.30 - Action upon receipt of claim.

Code of Federal Regulations, 2013 CFR

2013-07-01

... in any other format, shall be scanned into a computer and uploaded onto the TSCA database so that it... Medicine, Armed Forces Institute of Pathology, 1335 E. West Highway, #6-100, Silver Spring, MD 20910-6254...

Contact dynamics math model

NASA Technical Reports Server (NTRS)

Glaese, John R.; Tobbe, Patrick A.

1986-01-01

The Space Station Mechanism Test Bed consists of a hydraulically driven, computer controlled six degree of freedom (DOF) motion system with which docking, berthing, and other mechanisms can be evaluated. Measured contact forces and moments are provided to the simulation host computer to enable representation of orbital contact dynamics. This report describes the development of a generalized math model which represents the relative motion between two rigid orbiting vehicles. The model allows motion in six DOF for each body, with no vehicle size limitation. The rotational and translational equations of motion are derived. The method used to transform the forces and moments from the sensor location to the vehicles' centers of mass is also explained. Two math models of docking mechanisms, a simple translational spring and the Remote Manipulator System end effector, are presented along with simulation results. The translational spring model is used in an attempt to verify the simulation with compensated hardware in the loop results.

Users manual: Dynamics of two bodies connected by an elastic tether, six degrees of freedom forebody and five degrees of freedom decelerator

NASA Technical Reports Server (NTRS)

Doyle, G. R., Jr.; Burbick, J. W.

1974-01-01

The equations of motion and a computer program for the dynamics of a six degree of freedom body joined to a five degree of freedom body by a quasilinear elastic tether are presented. The forebody is assumed to be a completely general rigid body with six degrees of freedom; the decelerator is also assumed to be rigid, but with only five degrees of freedom (symmetric about its longitudinal axis). The tether is represented by a spring and dashpot in parallel, where the spring constant is a function of tether elongation. Lagrange's equation is used to derive the equations of motion with the Lagrange multiplier technique used to express the constraint provided by the tether. A computer program is included which provides a time history of the dynamics of both bodies and the tension in the tether.

The influence of ligament modelling strategies on the predictive capability of finite element models of the human knee joint.

PubMed

Naghibi Beidokhti, Hamid; Janssen, Dennis; van de Groes, Sebastiaan; Hazrati, Javad; Van den Boogaard, Ton; Verdonschot, Nico

2017-12-08

In finite element (FE) models knee ligaments can represented either by a group of one-dimensional springs, or by three-dimensional continuum elements based on segmentations. Continuum models closer approximate the anatomy, and facilitate ligament wrapping, while spring models are computationally less expensive. The mechanical properties of ligaments can be based on literature, or adjusted specifically for the subject. In the current study we investigated the effect of ligament modelling strategy on the predictive capability of FE models of the human knee joint. The effect of literature-based versus specimen-specific optimized material parameters was evaluated. Experiments were performed on three human cadaver knees, which were modelled in FE models with ligaments represented either using springs, or using continuum representations. In spring representation collateral ligaments were each modelled with three and cruciate ligaments with two single-element bundles. Stiffness parameters and pre-strains were optimized based on laxity tests for both approaches. Validation experiments were conducted to evaluate the outcomes of the FE models. Models (both spring and continuum) with subject-specific properties improved the predicted kinematics and contact outcome parameters. Models incorporating literature-based parameters, and particularly the spring models (with the representations implemented in this study), led to relatively high errors in kinematics and contact pressures. Using a continuum modelling approach resulted in more accurate contact outcome variables than the spring representation with two (cruciate ligaments) and three (collateral ligaments) single-element-bundle representations. However, when the prediction of joint kinematics is of main interest, spring ligament models provide a faster option with acceptable outcome. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Efficiency of Computer-Aided Instruction and Creative Drama on Academic Achievement in Teaching of Integers to Seventh Grade Students

ERIC Educational Resources Information Center

Kaplan, Abdullah; Özturk, Mesut; Ertör, Eren

2013-01-01

This study aims to compare computer-aided instruction, creative drama and traditional teaching methods in teaching of Integers to the seventh grade students. The study was conducted in a primary school with eighty-seven students (N=87) in a county of Agri, in spring term of academic year 2011-2012. A non equivalent control group quasi experimental…

Transnational Threats: Blending Law Enforcement and Military Strategies

DTIC Science & Technology

2000-11-01

Providing Humanitarian Assistance Following NBC Accidents/Incidents: The Legal Considerations, Colorado Springs, CO: Institute for National Security Studies...draft of a position on cyber crime .36 The draft focused on such issues as extradition, mutual legal assistance, and trans-border computer searches. These...warfare also raises specific legal issues related to computer crime : what is a crime , who commits it, and what does the law say about it? 21. A

The effect of mechanical vibration on orthodontically induced root resorption.

PubMed

Yadav, Sumit; Dobie, Thomas; Assefnia, Amir; Kalajzic, Zana; Nanda, Ravindra

2016-09-01

To investigate the effect of low-frequency mechanical vibration (LFMV) on orthodontically induced root resorption. Forty male CD1, 12-week-old mice were used for the study. The mice were randomly divided into five groups: group 1 (baseline)-no spring and no mechanical vibration, group 2-orthodontic spring but no vibration, group 3-orthodontic spring and 5 Hz of vibration applied to the maxillary first molar, group 4-orthodontic spring and 10 Hz of vibration applied to maxillary first molar, and group 5-orthodontic spring and 20 Hz of vibration applied to maxillary first molar. In the different experimental groups, the first molar was moved mesially for 2 weeks using a nickel-titanium coil spring delivering 10 g of force. LFMVs were applied at 5 Hz, 10 Hz, and 20 Hz. Microfocus X-ray computed tomography imaging was used to analyze root resorption. Additionally, to understand the mechanism, we applied LFMV to MC3T3 cells, and gene expression analyses were done for receptor activator of nuclear factor kappa-B ligand (RANKL) and osteoprotegerin (OPG). Orthodontic tooth movement leads to decreased root volume (increased root resorption craters). Our in vivo experiments showed a trend toward increase in root volume with different frequencies of mechanical vibration. In vitro gene expression analyses showed that with 20 Hz of mechanical vibration, there was a significant decrease in RANKL and a significant increase in OPG expression. There was a trend toward decreased root resorption with different LFMVs (5 Hz, 10 Hz, and 20 Hz); however, it was not more statistically significant than the orthodontic-spring-only group.

Lagrangian photochemical modeling studies of the 1987 Antarctic spring vortex. I - Comparison with AAOE observations

NASA Technical Reports Server (NTRS)

Jones, R. L.; Austin, J.; Mckenna, D. S.; Anderson, J. G.; Fahey, D. W.; Farmer, C. B.; Vedder, J. F.

1989-01-01

Results from the Lagrangian photochemical model integrated along computed air parcel trajectories intersected by the ER-2 aircraft are presented and compared with AAOE observations. According to the model, the BrO observations made from the ER-2 within the dehydrated denitrified region are consistent with there being approximately 5 parts per trillion by volume of BrO(y) at 428 K in spring. Within the high ClO region, ozone destruction rates are expected to exceed 2 percent/d with approximately 80 percent due to the ClO dimer mechanism.

Computer program for the load and trajectory analysis of two DOF bodies connected by an elastic tether: Users manual

NASA Technical Reports Server (NTRS)

Doyle, G. R., Jr.; Burbick, J. W.

1973-01-01

The derivation of the differential equations of motion of a 3 Degrees of Freedom body joined to a 3 Degrees of Freedom body by an elastic tether. The tether is represented by a spring and dashpot in parallel. A computer program which integrates the equations of motion is also described. Although the derivation of the equations of motions are for a general system, the computer program is written for defining loads in large boosters recovered by parachutes.

ePatient Conference Explores Future of Personalized Medicine | NIH MedlinePlus the Magazine

MedlinePlus

... Javascript on. ePatient Conference Explores Future of Personalized Medicine Past Issues / Spring - Summer 2010 Table of Contents ... better in the digital future? What is personalized medicine? Some of the nation's top health researchers, computer ...

A rule based computer aided design system

NASA Technical Reports Server (NTRS)

Premack, T.

1986-01-01

A Computer Aided Design (CAD) system is presented which supports the iterative process of design, the dimensional continuity between mating parts, and the hierarchical structure of the parts in their assembled configuration. Prolog, an interactive logic programming language, is used to represent and interpret the data base. The solid geometry representing the parts is defined in parameterized form using the swept volume method. The system is demonstrated with a design of a spring piston.

NAVO MSRC Navigator. Spring 2003

DTIC Science & Technology

2003-01-01

computational model run on the IBM POWER4 (MARCELLUS) in support of the Airborne Laser Challenge Project II. The data were visualized using Alias|Wavefront Maya...Turbulence in a Jet Stream in the Airborne Laser Context High Performance Computing 11 Largest NAVO MSRC System Becomes Even Bigger and Better 11 Using the smp...centimeters (cm). The resolution requirement to resolve the microjets and the flow outside in the combustor is too severe for any single numerical method

NERVA dynamic analysis methodology, SPRVIB

NASA Technical Reports Server (NTRS)

Vronay, D. F.

1972-01-01

The general dynamic computer code called SPRVIB (Spring Vib) developed in support of the NERVA (nuclear engine for rocket vehicle application) program is described. Using normal mode techniques, the program computes kinematical responses of a structure caused by various combinations of harmonic and elliptic forcing functions or base excitations. Provision is made for a graphical type of force or base excitation input to the structure. A description of the required input format and a listing of the program are presented, along with several examples illustrating the use of the program. SPRVIB is written in FORTRAN 4 computer language for use on the CDC 6600 or the IBM 360/75 computers.

78 FR 72865 - Export Trade Certificate of Review

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-04

...., Carson City, NV Cobham, Arlington, VA Colt Defense, LLC, West Hartford, CT Computer Sciences Corporation...., Exton, PA ARINC Aerospace, Annapolis, MD Aurora Flight Sciences Corporation, Manassas, VA AUSCO, Inc... Springs, CA Science Applications International Corporation, McLean, VA Seal Science, Inc., Irvine, CA...

The transfer of land resources information into the public sector—The Texas experience

NASA Astrophysics Data System (ADS)

Wermund, E. G.

1980-03-01

Mapping of land resources and environmental geology was initiated in Texas toward better communication of geology to the public policy sector. Relevant mapping parameters have included terrain, substrate, active processes, economic resources, and hydrology as well as physical, chemical, and biologic properties. Land resources maps and reports have been prepared for public agencies and published for technical and nontechnical readers; sales of these articles are one indicator of public policy transfer. Single lectures or participation in symposia and colloquia for scientific societies have been valuable only for peer review or as a means to sharpen communicative skills. The most successful mechanisms of public policy transfer have been (1) in-state workshops and short courses for elected officials, Governmental employees, and interested citizens; (2) legislative testimonies; (3) active participation on interagency committees; (4) reviews and comments on planning statements; and (5) a temporary loan of personnel to another agency. Areas where these methods successfully have impacted public policy are reflected in the present quality of Section 208, Section 701, and coastal zone management planning; applications for surface-mining permits; and environmental impact statement records in Texas.

COSPAR, a platform for international cooperation in space research

NASA Astrophysics Data System (ADS)

Fellous, Jean-Louis

The Committee on Space Research (COSPAR) was founded by the International Council for Science (ICSU) in 1958, with the aim of favouring the dialogue between the USSR and USA in the time of the Cold War. Fifty-six years later, COSPAR is continuing its mission of service to the worldwide space research community. Thousands of scientists attend COSPAR assemblies, read and publish their results in its journals, participate in its workshops, colloquia and symposia, but many are unaware of the wealth of activities that COSPAR undertakes or supports. Many of them ignore the processes through which this organisation develops its activities, how it is structured, how to get involved in its governance, how to promote new initiatives with its help, etc. Young space scientists do not know the history of, and prominent roles played by COSPAR, past and present, and more importantly need to understand better the benefits that can be accrued from their involvement within COSPAR. This presentation will review these aspects and offer all interested scientists a detailed overview of COSPAR activities and plans for the future.

Mobilizing EPA's Comptox Chemistry Dashboard Data on Mobile Devices (ACS Spring Meeting)

EPA Science Inventory

The EPA’s National Center of Computational Toxicology (NCCT) Chemistry Dashboard provides access to chemistry data for about 720,000 chemical substances. The application is used to source, for example: physicochemical property data, bioassay screening data and functional use, and...

Coarse-grained protein-protein stiffnesses and dynamics from all-atom simulations

NASA Astrophysics Data System (ADS)

Hicks, Stephen D.; Henley, C. L.

2010-03-01

Large protein assemblies, such as virus capsids, may be coarse-grained as a set of rigid units linked by generalized (rotational and stretching) harmonic springs. We present an ab initio method to obtain the elastic parameters and overdamped dynamics for these springs from all-atom molecular-dynamics simulations of one pair of units at a time. The computed relaxation times of this pair give a consistency check for the simulation, and we can also find the corrective force needed to null systematic drifts. As a first application we predict the stiffness of an HIV capsid layer and the relaxation time for its breathing mode.

A Workshop on the Integration of Numerical and Symbolic Computing Methods Held in Saratoga Springs, New York on July 9-11, 1990

DTIC Science & Technology

1991-04-01

SUMMARY OF COMPLETED PROJECT (for public use) The summary (about 200 words) must be self-contained and intellegible to a scientifically literate reader...dialogue among re- searchers in symbolic methods and numerical computation, and their appli- cations in certain disciplines of artificial intelligence...Lozano-Perez Purdue University Artificial Intelligence Laboratory West Lafayette, IN 47907 Massachusetts Institute of Technology (317) 494-6181 545

Hydrological and geochemical processes constraining groundwater salinity in wetland areas related to evaporitic (karst) systems. A case study from Southern Spain

NASA Astrophysics Data System (ADS)

Gil-Márquez, J. M.; Barberá, J. A.; Andreo, B.; Mudarra, M.

2017-01-01

Chemical and isotopic evolution of groundwater in an evaporite karst plateau (including wetland areas and saline to hyper-saline springs) located at S Spain was studied. Physicochemical parameters, major ions and stable isotopes were analyzed in rain, brine spring, wetland and leakage water samples, from which the most common mineral saturation indexes were computed and geochemical and isotopic modelling were performed. Results show an apparent relationship between the elevation of brine springs and their water mineralization, indicating that drainage at higher altitude may be associated to gravity-driven flows, since brackish groundwater is isotopically fractionated due to evaporation. On the other hand, the lower altitude springs could drain deeper flows with longer residence time, resulting in highly mineralized and warmer (briny) groundwater. The dissolution of halite and gypsum has proved to be the main geochemical processes, which are favored by the great ionic strength of groundwater. Calcite precipitation occurs in brackish waters draining wetlands, being boosted by common ion effect (when CaSO4 waters are present) and solute concentration caused by evaporation. Modelling results strongly support the hypothesis that most of the selected springs geochemically evolve in a common (S-N) flowpath. The methods used in this research contribute to a better understanding of the hydrogeological processes occurring in the studied evaporitic system, but also in equivalent hydrological environments worldwide.

Low band gap frequencies and multiplexing properties in 1D and 2D mass spring structures

NASA Astrophysics Data System (ADS)

Aly, Arafa H.; Mehaney, Ahmed

2016-11-01

This study reports on the propagation of elastic waves in 1D and 2D mass spring structures. An analytical and computation model is presented for the 1D and 2D mass spring systems with different examples. An enhancement in the band gap values was obtained by modeling the structures to obtain low frequency band gaps at small dimensions. Additionally, the evolution of the band gap as a function of mass value is discussed. Special attention is devoted to the local resonance property in frequency ranges within the gaps in the band structure for the corresponding infinite periodic lattice in the 1D and 2D mass spring system. A linear defect formed of a row of specific masses produces an elastic waveguide that transmits at the narrow pass band frequency. The frequency of the waveguides can be selected by adjusting the mass and stiffness coefficients of the materials constituting the waveguide. Moreover, we pay more attention to analyze the wave multiplexer and DE-multiplexer in the 2D mass spring system. We show that two of these tunable waveguides with alternating materials can be employed to filter and separate specific frequencies from a broad band input signal. The presented simulation data is validated through comparison with the published research, and can be extended in the development of resonators and MEMS verification.

NAVO MSRC Navigator. Spring 2006

DTIC Science & Technology

2006-01-01

all of these upgrades are complete, the effective computing power of the NAVO MSRC will be essentially tripled, as measured by sustainable ... performance on the HPCMP benchmark suite. All four of these systems will be configured with two gigabytes of memory per processor, IBM’s “Federation” inter

New Systems to Beat Swimming Program Frustration.

ERIC Educational Resources Information Center

Simpson, Scott J.

1980-01-01

A swimming program with effective student placement has been designed in Colorado Springs. The beginner level established by the American Red Cross is further broken down to accommodate children under the age of five. Use of computer facilities will assist in accurate program enrollment/completion records. (CJ)

Teaching Information Retrieval: Lessons from Cornell.

ERIC Educational Resources Information Center

Stewart, Linda Guyotte; Markiewicz, James

1986-01-01

This article describes two separate workshops offered to college faculty during the spring 1984 semester: one in online bibliographic searching, one in using computers to manage personal files of bibliographic references (examination of existing systems, types of software available). A telephone survey evaluation conducted 3 months after sessions…

Condom use less likely, high risk behavior more common at Spring break. Safe sex.

PubMed

1997-04-21

According to a Durex Sheik online survey of Panama City Beach, Florida, spring breakers, college students are actually less sexually active during spring break than they are back on campus, despite long-standing perceptions to the contrary. That's the good news. The bad news is that those having sex at spring break are more likely to be doing so with several different partners and less likely to be using condoms than they are back at school. The survey of 664 college students, who responded via beach side computers hooked up to the Internet, showed that 36% of spring breakers hadn't had any sexual encounters during their week at the beach vs. 23% who said they had no such encounters during a typical week at school. 23% said they had one encounter per week during spring break, while 18% had two or three liaisons, 9% had four or five, and 13% had more than five. A closer look at those who had more than five partners per week reveals even more startling figures: 47% said they did not use a condom during any of their encounters during spring break vs. 23% for all spring breakers and 15% for those who were with only one partner. And among those who had more than five partners and for whom alcohol was involved in all of their encounters, a shocking 74% didn't use condoms. "We conducted this survey to better understand sexual attitudes and behavior at spring break," said Catherine Taylor, Durex. "What we found is a small but dangerous group of individuals who are engaging in very risky behavior, supporting the belief that we need to talk to young adults in their own language to teach them how condoms can be a normal part of a healthy intimate relationship." To normalize the acceptance of condoms, two 7-foot-tall Durex condom characters handed out 70,000 free Durex Sheik condom samples in Panama City Beach. Durex Sheik also hosted an event with MTV "Singled Out" star Carmen Electra and conducted a hands-on game in which contestants, racing against the clock, slipped condoms on a demonstrator--blindfolded. full text

Physical and Hydrological Meaning of the Spectral Information from Hydrodynamic Signals at Karst Springs

NASA Astrophysics Data System (ADS)

Dufoyer, A.; Lecoq, N.; Massei, N.; Marechal, J. C.

2017-12-01

Physics-based modeling of karst systems remains almost impossible without enough accurate information about the inner physical characteristics. Usually, the only available hydrodynamic information is the flow rate at the karst outlet. Numerous works in the past decades have used and proven the usefulness of time-series analysis and spectral techniques applied to spring flow, precipitations or even physico-chemical parameters, for interpreting karst hydrological functioning. However, identifying or interpreting the karst systems physical features that control statistical or spectral characteristics of spring flow variations is still challenging, not to say sometimes controversial. The main objective of this work is to determine how the statistical and spectral characteristics of the hydrodynamic signal at karst springs can be related to inner physical and hydraulic properties. In order to address this issue, we undertake an empirical approach based on the use of both distributed and physics-based models, and on synthetic systems responses. The first step of the research is to conduct a sensitivity analysis of time-series/spectral methods to karst hydraulic and physical properties. For this purpose, forward modeling of flow through several simple, constrained and synthetic cases in response to precipitations is undertaken. It allows us to quantify how the statistical and spectral characteristics of flow at the outlet are sensitive to changes (i) in conduit geometries, and (ii) in hydraulic parameters of the system (matrix/conduit exchange rate, matrix hydraulic conductivity and storativity). The flow differential equations resolved by MARTHE, a computer code developed by the BRGM, allows karst conduits modeling. From signal processing on simulated spring responses, we hope to determine if specific frequencies are always modified, thanks to Fourier series and multi-resolution analysis. We also hope to quantify which parameters are the most variable with auto-correlation analysis: first results seem to show higher variations due to conduit conductivity than the ones due to matrix/conduit exchange rate. Future steps will be using another computer code, based on double-continuum approach and allowing turbulent conduit flow, and modeling a natural system.

Preface

NASA Astrophysics Data System (ADS)

Jakovics, A.

2007-06-01

The International Scientific Colloquium "Modelling for Material Processing" took place last year on June 8-9. It was the fourth time the colloquium was organized. The first colloquium took place in 1999. All colloquia were organized by the University of Latvia together with Leibniz University of Hannover (Germany) that signifies a long-term tradition (since 1988) of scientific cooperation between researchers of these two universities in the field of electrothermal process modelling. During the last colloquium scientific reports in the field of mathematical modelling in industrial electromagnetic applications for different materials (liquid metals, semiconductor technology, porous materials, melting of oxides and inductive heating) were presented. 70 researchers from 10 countries attended the colloquium. The contributions included about 30 oral presentations and 12 posters. The most illustrative presentations (oral and poster) in the field of MHD were selected for publication in a special issue of the international journal "Magnetohydrodynamics". Traditionally, many reports of the colloquium discuss the problems of MHD methods and devices applied to the metallurgical technologies and processes of semiconductor crystal growth. The new results illustrate the influence of combined electromagnetic fields on the hydrodynamics and heat/mass transfer in melts. The presented reports demonstrate that the models for simulation of turbulent liquid metal flows in melting furnaces, crystallization of alloys and single crystal growth in electromagnetic fields have become much more complex. The adequate description of occurring physical phenomena and the use of high performance computer and clusters allow to reduce the number of experiments in industrial facilities. The use of software and computers for modelling technological and environmental processes has a very long history at the University of Latvia. The first modelling activities in the field of industrial MHD applications had led to the establishment of the chair of Electrodynamics and Continuum Mechanics in 1970, the first head of which was professor Juris Mikelsons. In the early 90's, when all research institutions in our country underwent dramatic changes, not all research directions and institutions managed to adapt successfully to the new conditions. Fortunately, the people who were involved in computer modelling of physical processes were among the most successful. First, the existing and newly established contacts in Western Europe were used actively to reorient the applied researches in the directions actively studied at the universities and companies, which were the partners of the University of Latvia. As a result, research groups involved in these activities successfully joined the international effort related to the application of computer models to industrial processes, and the scientific laboratory for Mathematical Modelling of Environmental and Technological Processes was founded in 1994. The second direction of modelling development was related to the application of computer-based models for the environmental and technological processes (e.g., sediment transport in harbours, heat transfer in building constructions) that were important for the companies and state institutions in Latvia. Currently, the field of engineering physics, the core of which is the computer modelling of technological and environmental processes, is one of the largest and most successfully developing parts of researches and educational programs at the Department of Physics of the University of Latvia with very good perspectives in the future for the development of new technologies and knowledge transfer.

ERDC MSRC Resource. High Performance Computing for the Warfighter. Spring 2006

DTIC Science & Technology

2006-01-01

named Ruby, and the HP/Compaq SC45, named Emerald , continue to add their unique sparkle to the ERDC MSRC computer infrastructure. ERDC invited the...configuration on B-52H purchased additional memory for the login nodes so that this part of the solution process could be done as a preprocessing step. On...application and system services. Of the service nodes, 10 are login nodes and 23 are input/output (I/O) server nodes for the Lustre file system (i.e., the

Engineering design manual of parachute decelerator characteristics for space shuttle solid rocket booster recovery

NASA Technical Reports Server (NTRS)

Mansfield, D. L.

1973-01-01

The design criteria and characteristics of parachutes for recovery of the solid rocket boosters used with the space shuttle launch are presented. A computer program for analyzing the requirements of the parachute decelerators is described. The computer inputs for both the drogue and main parachute decelerators are; (1) parachute size, (2) deployment conditions, (3) inflation times, (4) reefing times, (5) mass properties, (6) spring properties, and (7) aerodynamic coefficients. Graphs of the parachute performance are included.

Measuring Technological and Content Knowledge of Undergraduate Primary Teachers in Mathematics

NASA Astrophysics Data System (ADS)

Doukakis, Spyros; Chionidou-Moskofoglou, Maria; Mangina-Phelan, Eleni; Roussos, Petros

Twenty-five final-year undergraduate students of primary education who were attending a course on mathematics education participated in a research project during the 2009 spring semester. A repeated measures experimental design was used. Quantitative data on students' computer attitudes, self-efficacy in ICT, attitudes toward educational software, and self-efficacy in maths were collected. Data analysis showed a statistically non-significant improvement on participants' computer attitudes and self-efficacy in ICT and ES, but a significant improvement of self-efficacy in mathematics.

Young Investigator Program (8.5): Preventing Complex Failures of Human Interactive Systems with Erroneous Behavior Generation and Robust Human Task Behavior Patterns

DTIC Science & Technology

2017-11-13

behavior . The International Journal of Human-Computer Studies , 108, 105-121. https://doi.org/10.1016/j.ijhcs.2017.06.006 A second journal article...documenting the erroneous behavior generation approach and the case study analyses is currently being written. Planned submission is Spring 2017. RPPR...Belvoir, 2010. [3] A task-based taxonomy of erroneous human behavior . International Journal of Human-Computer Studies , 108:105–121, 2017. [4] M. L

Methods for estimating selected spring and fall low-flow frequency statistics for ungaged stream sites in Iowa, based on data through June 2014

USGS Publications Warehouse

Eash, David A.; Barnes, Kimberlee K.; O'Shea, Padraic S.

2016-09-19

A statewide study was led to develop regression equations for estimating three selected spring and three selected fall low-flow frequency statistics for ungaged stream sites in Iowa. The estimation equations developed for the six low-flow frequency statistics include spring (April through June) 1-, 7-, and 30-day mean low flows for a recurrence interval of 10 years and fall (October through December) 1-, 7-, and 30-day mean low flows for a recurrence interval of 10 years. Estimates of the three selected spring statistics are provided for 241 U.S. Geological Survey continuous-record streamgages, and estimates of the three selected fall statistics are provided for 238 of these streamgages, using data through June 2014. Because only 9 years of fall streamflow record were available, three streamgages included in the development of the spring regression equations were not included in the development of the fall regression equations. Because of regulation, diversion, or urbanization, 30 of the 241 streamgages were not included in the development of the regression equations. The study area includes Iowa and adjacent areas within 50 miles of the Iowa border. Because trend analyses indicated statistically significant positive trends when considering the period of record for most of the streamgages, the longest, most recent period of record without a significant trend was determined for each streamgage for use in the study. Geographic information system software was used to measure 63 selected basin characteristics for each of the 211streamgages used to develop the regional regression equations. The study area was divided into three low-flow regions that were defined in a previous study for the development of regional regression equations.Because several streamgages included in the development of regional regression equations have estimates of zero flow calculated from observed streamflow for selected spring and fall low-flow frequency statistics, the final equations for the three low-flow regions were developed using two types of regression analyses—left-censored and generalized-least-squares regression analyses. A total of 211 streamgages were included in the development of nine spring regression equations—three equations for each of the three low-flow regions. A total of 208 streamgages were included in the development of nine fall regression equations—three equations for each of the three low-flow regions. A censoring threshold was used to develop 15 left-censored regression equations to estimate the three fall low-flow frequency statistics for each of the three low-flow regions and to estimate the three spring low-flow frequency statistics for the southern and northwest regions. For the northeast region, generalized-least-squares regression was used to develop three equations to estimate the three spring low-flow frequency statistics. For the northeast region, average standard errors of prediction range from 32.4 to 48.4 percent for the spring equations and average standard errors of estimate range from 56.4 to 73.8 percent for the fall equations. For the northwest region, average standard errors of estimate range from 58.9 to 62.1 percent for the spring equations and from 83.2 to 109.4 percent for the fall equations. For the southern region, average standard errors of estimate range from 43.2 to 64.0 percent for the spring equations and from 78.1 to 78.7 percent for the fall equations.The regression equations are applicable only to stream sites in Iowa with low flows not substantially affected by regulation, diversion, or urbanization and with basin characteristics within the range of those used to develop the equations. The regression equations will be implemented within the U.S. Geological Survey StreamStats Web-based geographic information system application. StreamStats allows users to click on any ungaged stream site and compute estimates of the six selected spring and fall low-flow statistics; in addition, 90-percent prediction intervals and the measured basin characteristics for the ungaged site are provided. StreamStats also allows users to click on any Iowa streamgage to obtain computed estimates for the six selected spring and fall low-flow statistics.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garcia-Fernandez, Ignacio; Pla-Castells, Marta; Martinez-Dura, Rafael J.

A model of a cable and pulleys is presented that can be used in Real Time Computer Graphics applications. The model is formulated by the coupling of a damped spring and a variable coefficient wave equation, and can be integrated in more complex mechanical models of lift systems, such as cranes, elevators, etc. with a high degree of interactivity.

New Mexico High School Proficiency Examination. Spring, 1980 Test Results.

ERIC Educational Resources Information Center

Albuquerque Public Schools, NM.

The New Mexico High School Proficiency Examination covers five general content areas: (1) Community Resources; (2) Occupational Knowledge; (3) Consumer Economics; (4) Mental and Physical Health; and (5) Government and Law. Skills measured by the test are: Identification of Facts and Terms; Reading; Writing; Computation and Problem Solving. These…

A Survey of New Students in Spring 1997.

ERIC Educational Resources Information Center

Glyer-Culver, Betty, M.

In fall 1996, California's Los Rios Community College District (LRCCD) undertook several initiatives to increase enrollment, including the construction of state-of-the-art computer laboratories to meet demands for high tech training and the expansion of course offerings to non-traditional times. To evaluate the effectiveness of these efforts,…

Response of winter and spring wheat grain yields to meteorological variation

NASA Technical Reports Server (NTRS)

Feyerherm, A. M.; Kanemasu, E. T.; Paulsen, G. M.

1977-01-01

Mathematical models which quantify the relation of wheat yield to selected weather-related variables are presented. Other sources of variation (amount of applied nitrogen, improved varieties, cultural practices) have been incorporated in the models to explain yield variation both singly and in combination with weather-related variables. Separate models were developed for fall-planted (winter) and spring-planted (spring) wheats. Meteorological variation is observed, basically, by daily measurements of minimum and maximum temperatures, precipitation, and tabled values of solar radiation at the edge of the atmosphere and daylength. Two different soil moisture budgets are suggested to compute simulated values of evapotranspiration; one uses the above-mentioned inputs, the other uses the measured temperatures and precipitation but replaces the tabled values (solar radiation and daylength) by measured solar radiation and satellite-derived multispectral scanner data to estimate leaf area index. Weather-related variables are defined by phenological stages, rather than calendar periods, to make the models more universally applicable.

X-ray computed microtomography analysis of the influence of different agricultural treatments on the topsoil porosity of a Grey Brown Luvisol from Ontario

NASA Astrophysics Data System (ADS)

Taina, I. A.; Heck, R. J.; Scaiff, N. T.

2009-05-01

One of the most important applications of X-ray computed tomography (CT) for the study of soil is the characterization of the shape and spatial distribution of pores. Analysis of 3D X-ray CT image data, related to different pore categories, can provide insight to soil structural changes, which have implications in water infiltration and soil aeration, resulting from agricultural practices. The aim of this study was to evaluate changes in the spatial characteristics of voids, due to tillage practices, in the Ap horizon of an Orthic Grey- Brown Luvisol (located at the Elora Research Station of the University of Guelph). Undisturbed oriented soil samples were collected from ten plots representing different tillage treatments: spring moldboard plow, spring moldboard plow, cultivate and pack, fall moldboard plow, cultivate and pack, spring tandem disc, no cultivator, fall offset disc, fall offset disc, cultivate and pack, fall chisel plow, cultivate and pack, zero zone till (soys twin rows), zero tillage (long term), and zero tillage (corn residue removed in row, soys twin rows). Since the utilization of standardized classes, in the quantification of similar features, proved to be necessary in order to obtain comparable results, categories of pores, separated according to their size, circularity and orientation were considered in the interpretation of data. Total volume of pores and volume percentage of each class were calculated, revealing substantial differences among the analyzed soil samples.

Digital data sets that describe aquifer characteristics of the Rush Springs Aquifer in western Oklahoma

USGS Publications Warehouse

Runkle, D.L.; Becker, M.F.; Rea, Alan

1997-01-01

This diskette contains digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the Rush Spring aquifer in western Oklahoma. This area encompasses all or part of Blaine, Caddo, Canadian, Comanche, Custer, Dewey, Grady, Stephens, and Washita Counties. These digital data sets were developed by Mark F. Becker to use as input into a computer model that simulated ground-water flow in the Rush Springs aquifer (Mark F. Becker, U.S. Geological Survey, written commun., 1997). For the purposes of modeling the ground-water flow in the Rush Springs aquifer, Mark F. Becker (written commun., 1997) defined the Rush Springs aquifer to include the Rush Springs Formation, alluvial and terrace deposits along major streams, and parts of the Marlow Formations, particularly in the eastern part of the aquifer boundary area. The Permian-age Rush Springs Formation consists of highly cross-bedded sandstone with some interbedded dolomite and gypsum. The Rush Springs Formation is overlain by Quaternary-age alluvial and terrace deposits that consist of unconsolidated clay, silt, sand, and gravel. The Rush Springs Formation is underlain by the Permian-age Marlow Formation that consists of interbedded sandstones, siltstones, mudstones, gypsum-anhydrite, and dolomite beds (Mark F. Becker, written commun., 1997). The parts of the Marlow Formation that have high permeability and porosity are where the Marlow Formation is included as part of the Rush Springs aquifer. The Rush Springs aquifer underlies about 2,400 square miles of western Oklahoma and is an important source of water for irrigation, livestock, industrial, municipal, and domestic use. Irrigation wells are reported to have well yields greater than 1,000 gallons per minute (Mark F. Becker, written commun., 1997). Mark F. Becker created some of the aquifer boundaries, hydraulic conductivity, and recharge data sets by digitizing parts of previously published surficial geology maps. The hydraulic conductivity and recharge values are the input data to the ground-water flow model (Mark F. Becker, written commun., 1997). The water-level elevation data set was prepared at a scale of 1:250,000 by Mark F. Becker (written commun., 1997) from water levels measured in wells prior to the year 1950. Ground-water flow models are numerical representations that simplify and aggregate natural systems. Models are not unique; different combinations of aquifer characteristics may produce similar results. Therefore, values of hydraulic conductivity and recharge used in the model and presented in this data set are not precise, but are within a reasonable range when compared to independently collected data.

Global Snow-Cover Evolution from Twenty Years of Satellite Passive Microwave Data

USGS Publications Warehouse

Mognard, N.M.; Kouraev, A.V.; Josberger, E.G.

2003-01-01

Starting in 1979 with the SMMR (Scanning Multichannel Microwave Radiometer) instrument onboard the satellite NIMBUS-7 and continuing since 1987 with the SSMI (Special Sensor Microwave Imager) instrument on board the DMSP (Defence Meteorological Satellite Program) series, more then twenty years of satellite passive microwave data are now available. This dataset has been processed to analyse the evolution of the global snow cover. This work is part of the AICSEX project from the 5th Framework Programme of the European Community. The spatio-temporal evolution of the satellite-derived yearly snow maximum extent and the timing of the spring snow melt were estimated and analysed over the Northern Hemisphere. Significant differences between the evolution of the yearly maximum snow extent in Eurasia and in North America were found. A positive correlation between the maximum yearly snow cover extent and the ENSO index was obtained. High interannual spatio-temporal variability characterises the timing of snow melt in the spring. Twenty-year trends in the timing of spring snow melt have been computed and compared with spring air temperature trends for the same period and the same area. In most parts of Eurasia and in the central and western parts of North America the tendency has been for earlier snow melt. In northeastern Canada, a large area of positive trends, where snow melt timing starts later than in the early 1980s, corresponds to a region of positive trends of spring air temperature observed over the same period.

Seasonal functioning and dynamics of Caulerpa prolifera meadows in shallow areas: An integrated approach in Cadiz Bay Natural Park

NASA Astrophysics Data System (ADS)

Vergara, Juan J.; García-Sánchez, M. Paz; Olivé, Irene; García-Marín, Patricia; Brun, Fernando G.; Pérez-Lloréns, J. Lucas; Hernández, Ignacio

2012-10-01

The rhizophyte alga Caulerpa prolifera thrives in dense monospecific stands in the vicinity of meadows of the seagrass Cymodocea nodosa in Cadiz Bay Natural Park. The seasonal cycle of demographic and biometric properties, photosynthesis, and elemental composition (C:N:P) of this species were monitored bimonthly from March 2004 to March 2005. The number of primary assimilators peaked in spring as consequence of the new recruitment, reaching densities up to 104 assimilators·m-2. A second peak was recorded in late summer, with a further decrease towards autumn and winter. Despite this summer maximum, aboveground biomass followed a unimodal pattern, with a spring peak about 400 g dry weight·m-2. In conjunction to demographic properties of the population, a detailed biometric analysis showed that the percentage of assimilators bearing proliferations and the number of proliferations per assimilator were maximal in spring (100% and c.a. 17, respectively), and decreased towards summer and autumn. The size of the primary assimilators was minimal in spring (May) as a result of the new recruitments. However, the frond area per metre of stolon peaked in early spring and decreased towards the remainder of the year. The thallus area index (TAI) was computed from two different, independent approaches which both produced similar results, with a maximum TAI recorded in spring (transient values up to 18 m2·m-2). The relative contribution of primary assimilators and proliferations to TAI was also assessed. Whereas the number of proliferations accounted for most of the TAI peak in spring, its contribution decreased during the year, to a minimum in winter, where primary assimilators were the main contributors to TAI. The present study represents the first report of the seasonal dynamics of C. prolifera in south Atlantic Spanish coasts, and indicates the important contribution of this primary producer in shallow coastal ecosystems.

76 FR 176 - Amended Certification Regarding Eligibility To Apply for Worker Adjustment Assistance

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-03

... Across Texas and Workers On-Site in: Austin, Houston, and Richardson, TX TA-W-73,102C Hewlett Packard..., solutions, engineering, supply chain, research, and product development services for personal computing...); Colorado Springs and Fort Collins, Colorado, and teleworkers across Colorado (TA-W-73,102A); Austin...

State of Washington Computer Use Survey.

ERIC Educational Resources Information Center

Beal, Jack L.; And Others

This report presents the results of a spring 1982 survey of a random sample of Washington public schools which separated findings according to school level (elementary, middle, junior high, or high school) and district size (either less than or greater than 2,000 enrollment). A brief review of previous studies and a description of the survey…

Practical Tools for Content Development: Pre-Service Teachers' Experiences and Perceptions

ERIC Educational Resources Information Center

Yurtseven Avci, Zeynep; Eren, Esra; Seckin Kapucu, Munise

2016-01-01

This study adopts phenomenology approach as the research design method to investigate pre-service teachers' experiences and perceptions on using practical tools for content development. The participants are twenty-four pre-service teachers who were taking Computer II course during 2013-2014 spring semester at a public university in Turkey. During…

easyCBM Norms. 2014 Edition. Technical Report #1409

ERIC Educational Resources Information Center

Saven, Jessica L.; Tindal, Gerald; Irvin, P. Shawn; Farley, Dan; Alonzo, Julie

2014-01-01

Previous norms for the easyCBM assessment system were computed using scores from all students who took each measure for every grade and benchmark season (fall, winter, and spring). During the 2013-­14 school year, new national norms were developed to more accurately (proportionately) represent reading and mathematics performance by two variables:…

Further Studies in Achievement Testing, Hearing Impaired Students. United States: Spring 1971.

ERIC Educational Resources Information Center

Gallaudet Coll., Washington, DC. Office of Demographic Studies.

Reported are four studies resulting from achievement testing activities from 1971 to 1973 with approximately 17,000 hearing impaired students from under 6 to over 21 years of age. The first study reports the relationships between selected achievement test scores (Paragraph Meaning and Arithmetic Computation subtests) and the following variables:…

Centrifugal Pump Experiment for Chemical Engineering Undergraduates

ERIC Educational Resources Information Center

Vanderslice, Nicholas; Oberto, Richard; Marrero, Thomas R.

2012-01-01

The purpose of this paper is to describe a Centrifugal Pump Experiment that provided an experiential learning experience to chemical engineering undergraduates at the University of Missouri in the spring of 2010 in the Unit Operations Laboratory course. Lab equipment was used by senior students with computer-based data and control technology. In…

Home-PC Usage and Achievement in English

ERIC Educational Resources Information Center

Naevdal, Folkvard

2007-01-01

This article investigates the relation between home computer use and performance in English at school. The sample consists of 656 tenth-class students (age 15-16) in upper-secondary schools in Bergen, Norway. Data collection took place in the spring of 2002 and was administrated by the county education office. After correcting for gender, subject…

Web-Based Mathematics Progress Monitoring in Second Grade

ERIC Educational Resources Information Center

Salaschek, Martin; Souvignier, Elmar

2014-01-01

We examined a web-based mathematics progress monitoring tool for second graders. The tool monitors the learning progress of two competences, number sense and computation. A total of 414 students from 19 classrooms in Germany were checked every 3 weeks from fall to spring. Correlational analyses indicate that alternate-form reliability was adequate…

Simulating the fate of fall- and spring-applied poultry litter nitrogen in corn production

USDA-ARS?s Scientific Manuscript database

Monitoring the fate of N derived from manures applied to fertilize crops is difficult, time consuming, and relatively expensive. But computer simulation models can help understand the interactions among various N processes in the soil-plant system and determine the fate of applied N. The RZWQM2 was ...

Hydrologic characterization for Spring Creek and hydrologic budget and model scenarios for Sheridan Lake, South Dakota, 1962-2007

USGS Publications Warehouse

Driscoll, Daniel G.; Norton, Parker A.

2009-01-01

The U.S. Geological Survey cooperated with South Dakota Game, Fish and Parks to characterize hydrologic information relevant to management of water resources associated with Sheridan Lake, which is formed by a dam on Spring Creek. This effort consisted primarily of characterization of hydrologic data for a base period of 1962 through 2006, development of a hydrologic budget for Sheridan Lake for this timeframe, and development of an associated model for simulation of storage deficits and drawdown in Sheridan Lake for hypothetical release scenarios from the lake. Historically, the dam has been operated primarily as a 'pass-through' system, in which unregulated outflows pass over the spillway; however, the dam recently was retrofitted with an improved control valve system that would allow controlled releases of about 7 cubic feet per second (ft3/s) or less from a fixed depth of about 60 feet (ft). Development of a hydrologic budget for Sheridan Lake involved compilation, estimation, and characterization of data sets for streamflow, precipitation, and evaporation. The most critical data need was for extrapolation of available short-term streamflow records for Spring Creek to be used as the long-term inflow to Sheridan Lake. Available short-term records for water years (WY) 1991-2004 for a gaging station upstream from Sheridan Lake were extrapolated to WY 1962-2006 on the basis of correlations with streamflow records for a downstream station and for stations located along two adjacent streams. Comparisons of data for the two streamflow-gaging stations along Spring Creek indicated that tributary inflow is approximately proportional to the intervening drainage area, which was used as a means of estimating tributary inflow for the hydrologic budget. Analysis of evaporation data shows that sustained daily rates may exceed maximum monthly rates by a factor of about two. A long-term (1962-2006) hydrologic budget was developed for computation of reservoir outflow from Sheridan Lake for the historical pass-through operating system. Two inflow components (stream inflow and precipitation) and one outflow component (evaporation) were considered. The hydrologic budget uses monthly time steps within a computational year that includes two 6-month periods - May through October, for which evaporation is accounted for, and November through April, when evaporation is considered negligible. Results indicate that monthly evaporation rates can substantially exceed inflow during low-flow periods, and potential exists for outflows to begin approaching zero-flow conditions substantially prior to the onset of zero-inflow conditions, especially when daily inflow and evaporation are considered. Results also indicate that September may be the month for greatest potential benefit for enhancing fish habitat and other ecosystem values in downstream reaches of Spring Creek with managed releases of cool water. Computed monthly outflows from Sheridan Lake for September are less than 1.0 ft3/s for 8 of the 44 years (18 percent) and are less than 2.0 ft3/s for 14 of the 44 years (32 percent). Conversely, none of the computed outflows for May are less than 2.0 ft3/s. A short-term (July through September 2007) data set was used to calculate daily evaporation from Sheridan Lake and to evaluate the applicability of published pan coefficients. Computed values of pan coefficients of approximately 1.0 and 1.1 for two low-flow periods are larger than the mean annual pan coefficient of 0.74 for the area that is reported in the literature; however, the computed values are consistent with pan coefficients reported elsewhere for similar late summer and early fall periods. Thus, these results supported the use of variable monthly pan coefficients for the long-term hydrologic budget. A hydrologic model was developed using the primary components of the hydrologic budget and was used to simulate monthly storage deficits and drawdown for Sheridan Lake using hypothetical

The Cognitive Predictors of Computational Skill with Whole versus Rational Numbers: An Exploratory Study.

PubMed

Seethaler, Pamela M; Fuchs, Lynn S; Star, Jon R; Bryant, Joan

2011-10-01

The purpose of the present study was to explore the 3(rd)-grade cognitive predictors of 5th-grade computational skill with rational numbers and how those are similar to and different from the cognitive predictors of whole-number computational skill. Students (n = 688) were assessed on incoming whole-number calculation skill, language, nonverbal reasoning, concept formation, processing speed, and working memory in the fall of 3(rd) grade. Students were followed longitudinally and assessed on calculation skill with whole numbers and with rational numbers in the spring of 5(th) grade. The unique predictors of skill with whole-number computation were incoming whole-number calculation skill, nonverbal reasoning, concept formation, and working memory (numerical executive control). In addition to these cognitive abilities, language emerged as a unique predictor of rational-number computational skill.

The Cognitive Predictors of Computational Skill with Whole versus Rational Numbers: An Exploratory Study

PubMed Central

Seethaler, Pamela M.; Fuchs, Lynn S.; Star, Jon R.; Bryant, Joan

2011-01-01

The purpose of the present study was to explore the 3rd-grade cognitive predictors of 5th-grade computational skill with rational numbers and how those are similar to and different from the cognitive predictors of whole-number computational skill. Students (n = 688) were assessed on incoming whole-number calculation skill, language, nonverbal reasoning, concept formation, processing speed, and working memory in the fall of 3rd grade. Students were followed longitudinally and assessed on calculation skill with whole numbers and with rational numbers in the spring of 5th grade. The unique predictors of skill with whole-number computation were incoming whole-number calculation skill, nonverbal reasoning, concept formation, and working memory (numerical executive control). In addition to these cognitive abilities, language emerged as a unique predictor of rational-number computational skill. PMID:21966180

Training the Future - Swamp Work Activities

NASA Image and Video Library

2017-07-19

In the Swamp Works laboratory at NASA's Kennedy Space Center in Florida, student interns, from the left, Jeremiah House, Thomas Muller and Austin Langdon are joining agency scientists, contributing in the area of Exploration Research and Technology. House is studying computer/electrical engineering at John Brown University in Siloam Springs, Arkansas. Muller is pursuing a degree in computer engineering and control systems and Florida Tech. Langdon is an electrical engineering major at the University of Kentucky. The agency attracts its future workforce through the NASA Internship, Fellowships and Scholarships, or NIFS, Program.

Optical Computing. Organization of the 1993 Photonics Science Topical Meetings Held in Palm Springs, California on March 16 - 19, 1993. Technical Digest Series, Volume 7

DTIC Science & Technology

1993-03-19

network Implementation using 9:20 am asymmetric Fabry-Perot modulators, Andrew Jennings, Brian OWA3 Multiwavelength optical half adder, Pochi Yeh... multiwavelength optical half adder. (p. 68) nects. (p. 96) 9:40 am 2:50 pm OWA4 Wavelength multiplexed computer-generated volume OWC3 Content addramble...ATMOS and OSCAR are RACE projects, mentioned in the text shape this into new systems architectures, ("optical ether"). Broadly speaking, this has led to

Pan-European seasonal trends and recent changes of drought frequency and severity

NASA Astrophysics Data System (ADS)

Spinoni, Jonathan; Naumann, Gustavo; Vogt, Jürgen V.

2017-01-01

In the last decades drought has become one of the natural disasters with most relevant impacts in Europe and this not only in water scarce areas such as the Mediterranean that are inclined to such events. As a complex natural phenomenon, drought is characterized by many hydro-meteorological aspects, a large variety of possible impacts and definitions. This study focuses on meteorological drought, investigated by using indicators that include precipitation and potential evapotranspiration (PET), i.e. the Standardized Precipitation Index (SPI) and the Standardized Precipitation-Evapotranspiration Index (SPEI). These indicators account for the lack of precipitation and the drying effects of hot temperatures and in this study have been computed for short-accumulation periods (3-month) to capture the seasonality of droughts. The input variables, monthly precipitation and temperature for 1950-2015, stem from daily gridded E-OBS data and indicators were computed on regular grids spanning over the whole of Europe. PET was calculated from minimum and maximum temperatures using the Hargreaves-Samani formulation. Monthly precipitation and PET have then been used to compute the SPI-3 and the SPEI-3 time series. From these series drought events were defined at seasonal scale and trends of frequency and severity of droughts and extreme droughts were analyzed for the periods 1950-2015 and 1981-2015. According to the SPI (driven by precipitation), results show a statistically significant tendency towards less frequent and severe drought events over North-Eastern Europe, especially in winter and spring, and a moderate opposite tendency over Southern Europe, especially in spring and summer. According to the SPEI (driven by precipitation and temperature), Northern Europe shows similar wetting patterns, while Southern and Eastern Europe show a more remarkable drying tendency, especially in summer and autumn. Both for frequency and severity, the evolution towards drier conditions is more relevant in the last three decades over Central Europe in spring, the Mediterranean area in summer, and Eastern Europe in autumn.

Micrometeorological measurements at Ash Meadows and Corn Creek Springs, Nye and Clark counties, Nevada, 1986-87

USGS Publications Warehouse

Johnson, M.J.; Pupacko, Alex

1992-01-01

Micrometeorological data were collected at Ash Meadows and Corn Creek Springs, Nye and Clark Counties, Nevada, from October 1, 1986 through September 30, 1987. The data include accumulated measurements recorded hourly or every 30 minutes, at each site, for the following climatic variables: air temperature, wind speed, relative humidity, precipitation, solar radiation, net radiation, and soil-heat flux. Periodic sampling of sensible-heat flux and latent-heat flux were also recorded using 5-minute intervals of accumulated data. Evapotranspiration was calculated by both the eddy-correlation method and the Penman combination method. The data collected and the computer programs used to process the data are available separately on three magnetic diskettes in card-image format. (USGS)

The STAGS computer code

NASA Technical Reports Server (NTRS)

Almroth, B. O.; Brogan, F. A.

1978-01-01

Basic information about the computer code STAGS (Structural Analysis of General Shells) is presented to describe to potential users the scope of the code and the solution procedures that are incorporated. Primarily, STAGS is intended for analysis of shell structures, although it has been extended to more complex shell configurations through the inclusion of springs and beam elements. The formulation is based on a variational approach in combination with local two dimensional power series representations of the displacement components. The computer code includes options for analysis of linear or nonlinear static stress, stability, vibrations, and transient response. Material as well as geometric nonlinearities are included. A few examples of applications of the code are presented for further illustration of its scope.

Applications of multiple-constraint matrix updates to the optimal control of large structures

NASA Technical Reports Server (NTRS)

Smith, S. W.; Walcott, B. L.

1992-01-01

Low-authority control or vibration suppression in large, flexible space structures can be formulated as a linear feedback control problem requiring computation of displacement and velocity feedback gain matrices. To ensure stability in the uncontrolled modes, these gain matrices must be symmetric and positive definite. In this paper, efficient computation of symmetric, positive-definite feedback gain matrices is accomplished through the use of multiple-constraint matrix update techniques originally developed for structural identification applications. Two systems were used to illustrate the application: a simple spring-mass system and a planar truss. From these demonstrations, use of this multiple-constraint technique is seen to provide a straightforward approach for computing the low-authority gains.

Spring hydrograph simulation of karstic aquifers: Impacts of variable recharge area, intermediate storage and memory effects

NASA Astrophysics Data System (ADS)

Hosseini, Seiyed Mossa; Ataie-Ashtiani, Behzad; Simmons, Craig T.

2017-09-01

A simple conceptual rainfall-runoff model is proposed for the estimation of groundwater balance components in complex karst aquifers. In the proposed model the effects of memory length of different karst flow systems of base-flow, intermediate-flow, and quick-flow and also time variation of recharge area (RA) during a hydrological year were investigated. The model consists of three sub-models: soil moisture balance (SMB), epikarst balance (EPB), and groundwater balance (GWB) to simulate the daily spring discharge. The SMB and EPB sub-models utilize the mass conservation equation to compute the variation of moisture storages in the soil cover and epikarst, respectively. The GWB sub-model computes the spring discharge hydrograph through three parallel linear reservoirs for base-flow, intermediate-flow, and quick-flow. Three antecedent recharge indices are defined and embedded in the model structure to deal with the memory effect of three karst flow systems to antecedent recharge flow. The Sasan Karst aquifer located in the semi-arid region of south-west Iran with a continuous long-term (21-years) daily meteorological and discharge data are considered to describe model calibration and validation procedures. The effects of temporal variations of RA of karst formations during the hydrological year namely invariant RA, two RA (winter and summer), four RA (seasonal), and twelve RA (monthly) are assessed to determine their impact on the model efficiency. Results indicated that the proposed model with monthly-variant RA is able to reproduce acceptable simulation results based on modified Kling-Gupta efficiency (KGE = -0.83). The results of density-based global sensitivity analysis for dry (June to September) and a wet (October to May) period reveal the dominant influence of RA (with sensitivity indices equal to 0.89 and 0.93, respectively) in spring discharge simulation. The sensitivity of simulated spring discharge to memory effect of different karst formations during the dry period is greater than the wet period. In addition, the results reveal the important role of intermediate-flow system in the hydrological modeling of karst systems during the wet period. Precise estimation of groundwater budgets for a better decision making regarding water supplies from complex karst systems with long memory effect can considerably be improved by use of the proposed model.

American Government: An Introduction Using MicroCase with Distance Learners.

ERIC Educational Resources Information Center

Rosberg, William H.

In spring 1997, a project used MicroCase, a computer-based statistical analysis and data retrieval system, to offer an American Government class to distance students at Iowa's Kirkwood Community College (KCC). Students participated in the course at one of the college's 10 learning centers via a statewide fiber-optic network. MicroCase provided the…

ConfChem Conference on Flipped Classroom: Spring 2014 ConfChem Virtual Poster Session

ERIC Educational Resources Information Center

Belford, Robert E.; Stoltzfus, Matthew; Houseknecht, Justin B.

2015-01-01

This communication describes the virtual poster session of the Flipped Classroom online ConfChem conference that was hosted by the ACS CHED Committee on Computers in Chemical Education (CCCE) from May 9 to June 12, 2014. During the conference's online discussions, it became evident that multiple participants who were not presenting papers had been…

An Innovative Plant Genomics and Gene Annotation Program for High School, Community College, and University Faculty

ERIC Educational Resources Information Center

Hacisalihoglu, Gokhan; Hilgert, Uwe; Nash, E. Bruce; Micklos, David A.

2008-01-01

Today's biology educators face the challenge of training their students in modern molecular biology techniques including genomics and bioinformatics. The Dolan DNA Learning Center (DNALC) of Cold Spring Harbor Laboratory has developed and disseminated a bench- and computer-based plant genomics curriculum for biology faculty. In 2007, a five-day…

Partnerships for Change. Research.

ERIC Educational Resources Information Center

David, Jane L.

Based on visits to four Apple Classrooms of Tomorrow (ACOT) sites in the spring of 1990 and interviews with Apple ACOT staff, this paper represents the first round of a 3-year study for Apple Computer, Inc., about the role of ACOT in educational restructuring. An overview of the ACOT project is presented, and the evolution and structure of ACOT…

Understanding Resonance Graphs Using Easy Java Simulations (EJS) and Why We Use EJS

ERIC Educational Resources Information Center

Wee, Loo Kang; Lee, Tat Leong; Chew, Charles; Wong, Darren; Tan, Samuel

2015-01-01

This paper reports a computer model simulation created using Easy Java Simulation (EJS) for learners to visualize how the steady-state amplitude of a driven oscillating system varies with the frequency of the periodic driving force. The simulation shows (N = 100) identical spring-mass systems being subjected to (1) a periodic driving force of…

Spring 2006. Industry Study. Manufacturing Industry

DTIC Science & Technology

2006-01-01

ANALYSIS OF TRENDS Today the U.S. is the global leader in manufacturing innovation and technology . Continued advancements in both computing power and...than ninety percent of all annual U.S. patents as reported by the Department of Commerce. Through innovation and the application of new technology ...mobilization, innovation and technology , the manufacturing transformation, environmental balance, and international travel impressions

Local deformation for soft tissue simulation

PubMed Central

Omar, Nadzeri; Zhong, Yongmin; Smith, Julian; Gu, Chengfan

2016-01-01

ABSTRACT This paper presents a new methodology to localize the deformation range to improve the computational efficiency for soft tissue simulation. This methodology identifies the local deformation range from the stress distribution in soft tissues due to an external force. A stress estimation method is used based on elastic theory to estimate the stress in soft tissues according to a depth from the contact surface. The proposed methodology can be used with both mass-spring and finite element modeling approaches for soft tissue deformation. Experimental results show that the proposed methodology can improve the computational efficiency while maintaining the modeling realism. PMID:27286482

The evolution of the ISOLDE control system

NASA Astrophysics Data System (ADS)

Jonsson, O. C.; Catherall, R.; Deloose, I.; Drumm, P.; Evensen, A. H. M.; Gase, K.; Focker, G. J.; Fowler, A.; Kugler, E.; Lettry, J.; Olesen, G.; Ravn, H. L.; Isolde Collaboration

The ISOLDE on-line mass separator facility is operating on a Personal Computer based control system since spring 1992. Front End Computers accessing the hardware are controlled from consoles running Microsoft Windows ™ through a Novell NetWare4 ™ local area network. The control system is transparently integrated in the CERN wide office network and makes heavy use of the CERN standard office application programs to control and to document the running of the ISOLDE isotope separators. This paper recalls the architecture of the control system, shows its recent developments and gives some examples of its graphical user interface.

The evolution of the ISOLDE control system

NASA Astrophysics Data System (ADS)

Jonsson, O. C.; Catherall, R.; Deloose, I.; Evensen, A. H. M.; Gase, K.; Focker, G. J.; Fowler, A.; Kugler, E.; Lettry, J.; Olesen, G.; Ravn, H. L.; Drumm, P.

1996-04-01

The ISOLDE on-line mass separator facility is operating on a Personal Computer based control system since spring 1992. Front End Computers accessing the hardware are controlled from consoles running Microsoft Windows® through a Novell NetWare4® local area network. The control system is transparently integrated in the CERN wide office network and makes heavy use of the CERN standard office application programs to control and to document the running of the ISOLDE isotope separators. This paper recalls the architecture of the control system, shows its recent developments and gives some examples of its graphical user interface.

Non-linear shipboard shock analysis of the Tomahawk missile shock isolation system

NASA Technical Reports Server (NTRS)

Leifer, Joel; Gross, Michael

1987-01-01

The identification, quantification, computer modeling and verification of the Tomahawk nonlinear liquid spring shock isolation system in a surface ship Vertical Launch System (VLS) are discussed. The isolation system hardware and mode of operation is detailed in an effort to understand the nonlinearities. These nonlinearities are then quantified and modeled using the MSC/NASTRAN finite element code. The model was verified using experimental data from the Navel Ordnance Systems Center MIL-S-901 medium weight shock tests of August 1986. The model was then used to predict the Tomahawk response to the CG-53 USS Mobile Bay shock trials of May-June 1987. Results indicate that the model is an accurate mathematical representation of the physical system either functioning as designed or in an impaired condition due to spring failure.

Parameter Optimization of Pseudo-Rigid-Body Models of MRI-Actuated Catheters

PubMed Central

Greigarn, Tipakorn; Liu, Taoming; Çavuşoğlu, M. Cenk

2016-01-01

Simulation and control of a system containing compliant mechanisms such as cardiac catheters often incur high computational costs. One way to reduce the costs is to approximate the mechanisms with Pseudo-Rigid-Body Models (PRBMs). A PRBM generally consists of rigid links connected by spring-loaded revolute joints. The lengths of the rigid links and the stiffnesses of the springs are usually chosen to minimize the tip deflection differences between the PRBM and the compliant mechanism. In most applications, only the relationship between end load and tip deflection is considered. This is obviously not applicable for MRI-actuated catheters which is actuated by the coils attached to the body. This paper generalizes PRBM parameter optimization to include loading and reference points along the body. PMID:28261009

Chaos on the conveyor belt.

PubMed

Sándor, Bulcsú; Járai-Szabó, Ferenc; Tél, Tamás; Néda, Zoltán

2013-04-01

The dynamics of a spring-block train placed on a moving conveyor belt is investigated both by simple experiments and computer simulations. The first block is connected by a spring to an external static point and, due to the dragging effect of the belt, the blocks undergo complex stick-slip dynamics. A qualitative agreement with the experimental results can be achieved only by taking into account the spatial inhomogeneity of the friction force on the belt's surface, modeled as noise. As a function of the velocity of the conveyor belt and the noise strength, the system exhibits complex, self-organized critical, sometimes chaotic, dynamics and phase transition-like behavior. Noise-induced chaos and intermittency is also observed. Simulations suggest that the maximum complexity of the dynamical states is achieved for a relatively small number of blocks (around five).

The Extent of Instructor Participation in an Online Computer Science Course How Much Is Enough?

ERIC Educational Resources Information Center

Arslanyilmaz, Abdurrahman; Sullins, John

2013-01-01

This study compares the discussion participation and performance of 7 undergraduate students enrolled in an e-commerce programming course during the spring semester of 2010 to that of 13 students enrolled in the same course during fall of that year. In the former course, the instructor participated in the required discussion only at the very end…

75 FR 47490 - Raisins Produced From Grapes Grown In California; Use of Estimated Trade Demand to Compute Volume...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-06

... this spring; and the potential for higher prices in the wine and juice markets, which compete for...-term benefits of this action are expected to outweigh the costs. The committee believes that with no... NS raisin producers benefit more from those raisins which are free tonnage, a lower free tonnage...

Using Computer-Assisted Personalized Assignment System in a Large-Enrollment General Physics

ERIC Educational Resources Information Center

Gok, Tolga

2010-01-01

The on-line tutoring system, LON-CAPA, was implemented in Introductory Calculus-Based Physics-II course at Colorado School of Mines in fall 2008 and spring 2009. In this paper, the features and the case study of the LON-CAPA implementation were described. The performance data obtained from the scores of students enrolled in the course represented…

NAVO MSRC Navigator. Spring 2008

DTIC Science & Technology

2008-01-01

EINSTEIN and DAVINCI Come to the MSRC The Porthole 19 Visitors to the Naval Oceanographic Office Major Shared Resource Center Navigator Tools and...traditionally considered one of the leading track guidance tools for forecasters. As an example, we consider the case of Hurricane Figure 2. The...MSRC NAVIGATOR EINSTEIN and DAVINCI Come to the MSRC Christine Cuicchi, Computational Science and Applications Lead, NAVO MSRC The Technology

Using the US EPA's CompTox Dashboard to support identification and screening of emerging organic contaminants in the environment (ACS Spring National meeting) 2 of 7

EPA Science Inventory

The US EPA’s iCSS CompTox Dashboard is a curated, publicly accessible resource provided by the National Center for Computational Toxicology (https://comptox.epa.gov). The Dashboard provides support for toxicology and risk assessment within and external to the EPA (including ToxC...

Surface Water Data at Los Alamos National Laboratory: 2002 Water Year

DOE Office of Scientific and Technical Information (OSTI.GOV)

D.A. Shaull; D. Ortiz; M.R. Alexander

2003-03-03

The principal investigators collected and computed surface water discharge data from 34 stream-gaging stations that cover most of Los Alamos National Laboratory and one at Bandelier National Monument. Also included are discharge data from three springs--two that flow into Canon de Valle and one that flows into Water Canyon--and peak flow data from 16 stations.

Surface Water Data at Los Alamos National Laboratory 2006 Water Year

DOE Office of Scientific and Technical Information (OSTI.GOV)

R.P. Romero, D. Ortiz, G. Kuyumjian

2007-08-01

The principal investigators collected and computed surface water discharge data from 44 stream-gaging stations that cover most of Los Alamos National Laboratory and one at Bandelier National Monument. Also included are discharge data from three springs--two that flow into Canon de Valle and one that flows into Water Canyon--and peak flow data for 44 stations.

Mass-Spectrometry Based Structure Identification of "Known-Unknowns" Using the EPA's CompTox Dashboard (ACS Spring National Meeting) 4 of 7

EPA Science Inventory

The CompTox Dashboard is a publicly accessible database provided by the National Center for Computational Toxicology at the US-EPA. The dashboard provides access to a database containing ~720,000 chemicals and integrates a number of our public-facing projects (e.g. ToxCast and Ex...

1-to-1 Computing: A Measure of Success

ERIC Educational Resources Information Center

O'Hanlon, Charlene

2007-01-01

When Texas' Technology Immersion Project began in the spring of 2004, a grant from the US Department of Education allowed a parallel project to launch--eTxTIP--to evaluate and measure the success of the program, which equips middle school students in high-risk, high-need areas with laptops. Data is beginning to come in on several of the first…

A Simple Experiment for Determining the Elastic Constant of a Fine Wire

ERIC Educational Resources Information Center

Freeman, W. Larry; Freda, Ronald F.

2007-01-01

Many general physics laboratories involve the use of springs to demonstrate Hooke's law, and much ado is made about how this can be used as a model for describing the elastic characteristics of materials at the molecular or atomic level. In recent years, the proliferation of computers, and appropriate sensors, have made it possible to demonstrate…

Spring 2006. Industry Study. Information Technology Industry

DTIC Science & Technology

2006-01-01

unclassified c . THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 i Information Technology 2006 ABSTRACT...integration of processors, coprocessors, memory, storage, etc. into a user-programmable final product. C . Software (Apple, Oracle): These firms...able to support the U.S. national security interests. C . Manufacturing: The personal computer manufacturing industry has also changed considerably

Frost Forecasting for Fruitgrowers

NASA Technical Reports Server (NTRS)

Martsolf, J. D.; Chen, E.

1983-01-01

Progress in forecasting from satellite data reviewed. University study found data from satellites displayed in color and used to predict frost are valuable aid to agriculture. Study evaluated scheme to use Earth-temperature data from Geostationary Operational Environmental Satellite in computer model that determines when and where freezing temperatures endanger developing fruit crops, such as apples, peaches and cherries in spring and citrus crops in winter.

Motorized CPM/CAM physiotherapy device with sliding-mode Fuzzy Neural Network control loop.

PubMed

Ho, Hung-Jung; Chen, Tien-Chi

2009-11-01

Continuous passive motion (CPM) and controllable active motion (CAM) physiotherapy devices promote rehabilitation of damaged joints. This paper presents a computerized CPM/CAM system that obviates the need for mechanical resistance devices such as springs. The system is controlled by a computer which performs sliding-mode Fuzzy Neural Network (FNN) calculations online. CAM-type resistance force is generated by the active performance of an electric motor which is controlled so as to oppose the motion of the patient's leg. A force sensor under the patient's foot on the device pedal provides data for feedback in a sliding-mode FNN control loop built around the motor. Via an active impedance control feedback system, the controller drives the motor to behave similarly to a damped spring by generating and controlling the amplitude and direction of the pedal force in relation to the patient's leg. Experiments demonstrate the high sensitivity and speed of the device. The PC-based feedback nature of the control loop means that sophisticated auto-adaptable CPM/CAM custom-designed physiotherapy becomes possible. The computer base also allows extensive data recording, data analysis and network-connected remote patient monitoring.

Improved ALE mesh velocities for complex flows

DOE PAGES

Bakosi, Jozsef; Waltz, Jacob I.; Morgan, Nathaniel Ray

2017-05-31

A key choice in the development of arbitrary Lagrangian-Eulerian solution algorithms is how to move the computational mesh. The most common approaches are smoothing and relaxation techniques, or to compute a mesh velocity field that produces smooth mesh displacements. We present a method in which the mesh velocity is specified by the irrotational component of the fluid velocity as computed from a Helmholtz decomposition, and excess compression of mesh cells is treated through a noniterative, local spring-force model. This approach allows distinct and separate control over rotational and translational modes. In conclusion, the utility of the new mesh motion algorithmmore » is demonstrated on a number of 3D test problems, including problems that involve both shocks and significant amounts of vorticity.« less

Integrating multiple genomic data to predict disease-causing nonsynonymous single nucleotide variants in exome sequencing studies.

PubMed

Wu, Jiaxin; Li, Yanda; Jiang, Rui

2014-03-01

Exome sequencing has been widely used in detecting pathogenic nonsynonymous single nucleotide variants (SNVs) for human inherited diseases. However, traditional statistical genetics methods are ineffective in analyzing exome sequencing data, due to such facts as the large number of sequenced variants, the presence of non-negligible fraction of pathogenic rare variants or de novo mutations, and the limited size of affected and normal populations. Indeed, prevalent applications of exome sequencing have been appealing for an effective computational method for identifying causative nonsynonymous SNVs from a large number of sequenced variants. Here, we propose a bioinformatics approach called SPRING (Snv PRioritization via the INtegration of Genomic data) for identifying pathogenic nonsynonymous SNVs for a given query disease. Based on six functional effect scores calculated by existing methods (SIFT, PolyPhen2, LRT, MutationTaster, GERP and PhyloP) and five association scores derived from a variety of genomic data sources (gene ontology, protein-protein interactions, protein sequences, protein domain annotations and gene pathway annotations), SPRING calculates the statistical significance that an SNV is causative for a query disease and hence provides a means of prioritizing candidate SNVs. With a series of comprehensive validation experiments, we demonstrate that SPRING is valid for diseases whose genetic bases are either partly known or completely unknown and effective for diseases with a variety of inheritance styles. In applications of our method to real exome sequencing data sets, we show the capability of SPRING in detecting causative de novo mutations for autism, epileptic encephalopathies and intellectual disability. We further provide an online service, the standalone software and genome-wide predictions of causative SNVs for 5,080 diseases at http://bioinfo.au.tsinghua.edu.cn/spring.

Plant phenological records in northern Finland since the 18th century as retrieved from databases, archives and diaries for biometeorological research.

PubMed

Holopainen, Jari; Helama, Samuli; Lappalainen, Hanna; Gregow, Hilppa

2013-05-01

Plant phenological data from northern Finland, compiled from several sources, were examined as potential biometeorological indicators of climate change since the 18th century. A common feature of individual series was their sporadic nature. In addition to waning enthusiasm, wartime hardships and crop failures had caused gaps in recording observations during the 18th and 19th centuries. The present study's challenge was to combine separate records, as retrieved from several historical archives and personal diaries, into a single continuous series. To avoid possible biases due to the variability of data availability each year, each phenomenon-specific mean series was transformed into normalized site-specific index series. These series were compared to each other and to a regional instrumental temperature series (years 1802-2011). The inter-phenomena correlations were high. Moreover, a strong biometeorological response of the phenological series, most especially to monthly mean temperature in May, and seasonally to the April through June temperatures, was identified. This response focused on slightly later spring months compared to the responses in an earlier study conducted for southern Finland. The findings encouraged us to compute a total phenological index series as an average of all available phenomenon-specific index series for northern Finland. The earliest phenological springs were found as a cluster in the recent end of the record, whereas the anomalously-late phenological spring could be found through the centuries. This finding could indicate that potential future warming could result in an earlier onset of phenological springs (i.e. as experienced by the plants), with a remaining possibility of late phenological springs. To conclude, it was shown that the indices are reliable biometeorological indicators of the April through June temperature variations and thus of the climate variability in the region.

Restructuring the CS 1 classroom: Examining the effect of open laboratory-based classes vs. closed laboratory-based classes on Computer Science 1 students' achievement and attitudes toward computers and computer courses

NASA Astrophysics Data System (ADS)

Henderson, Jean Foster

The purpose of this study was to assess the effect of classroom restructuring involving computer laboratories on student achievement and student attitudes toward computers and computer courses. The effects of the targeted student attributes of gender, previous programming experience, math background, and learning style were also examined. The open lab-based class structure consisted of a traditional lecture class with a separate, unscheduled lab component in which lab assignments were completed outside of class; the closed lab-based class structure integrated a lab component within the lecture class so that half the class was reserved for lecture and half the class was reserved for students to complete lab assignments by working cooperatively with each other and under the supervision and guidance of the instructor. The sample consisted of 71 students enrolled in four intact classes of Computer Science I during the fall and spring semesters of the 2006--2007 school year at two southern universities: two classes were held in the fall (one at each university) and two classes were held in the spring (one at each university). A counterbalanced repeated measures design was used in which all students experienced both class structures for half of each semester. The order of control and treatment was rotated among the four classes. All students received the same amount of class and instructor time. A multivariate analysis of variance (MANOVA) via a multiple regression strategy was used to test the study's hypotheses. Although the overall MANOVA model was statistically significant, independent follow-up univariate analyses relative to each dependent measure found that the only significant research factor was math background: Students whose mathematics background was at the level of Calculus I or higher had significantly higher student achievement than students whose mathematics background was less than Calculus I. The results suggest that classroom structures that incorporate an open laboratory setting are just as effective on student achievement and attitudes as classroom structures that incorporate a closed laboratory setting. The results also suggest that math background is a strong predictor of student achievement in CS 1.

Force and Stress along Simulated Dissociation Pathways of Cucurbituril-Guest Systems.

PubMed

Velez-Vega, Camilo; Gilson, Michael K

2012-03-13

The field of host-guest chemistry provides computationally tractable yet informative model systems for biomolecular recognition. We applied molecular dynamics simulations to study the forces and mechanical stresses associated with forced dissociation of aqueous cucurbituril-guest complexes with high binding affinities. First, the unbinding transitions were modeled with constant velocity pulling (steered dynamics) and a soft spring constant, to model atomic force microscopy (AFM) experiments. The computed length-force profiles yield rupture forces in good agreement with available measurements. We also used steered dynamics with high spring constants to generate paths characterized by a tight control over the specified pulling distance; these paths were then equilibrated via umbrella sampling simulations and used to compute time-averaged mechanical stresses along the dissociation pathways. The stress calculations proved to be informative regarding the key interactions determining the length-force profiles and rupture forces. In particular, the unbinding transition of one complex is found to be a stepwise process, which is initially dominated by electrostatic interactions between the guest's ammoniums and the host's carbonyl groups, and subsequently limited by the extraction of the guest's bulky bicyclooctane moiety; the latter step requires some bond stretching at the cucurbituril's extraction portal. Conversely, the dissociation of a second complex with a more slender guest is mainly driven by successive electrostatic interactions between the different guest's ammoniums and the host's carbonyl groups. The calculations also provide information on the origins of thermodynamic irreversibilities in these forced dissociation processes.

Defining the Future; Planning with and for Technology in Higher Education. Proceedings of the EDUCOM Spring Conference (Washington, D.C., April 3-4, 1975).

ERIC Educational Resources Information Center

Interuniversity Communications Council (EDUCOM), Princeton, NJ.

Following the keynote address on the importance of planning and the changing style of management in colleges and universities, various prepared papers developed the meeting theme of using technology in college and university planning. William Massey described the development and use of a computer model for strategic planning at Stanford. Edmund…

Assessing forest vegetation and fire simulation model performance after the Cold Springs wildfire, Washington USA

Treesearch

Susan Hummel; Maureen Kennedy; E. Ashley Steel

2012-01-01

Given that resource managers rely on computer simulation models when it is difficult or expensive to obtain vital information directly, it is important to evaluate how well a particular model satisfies applications for which it is designed. The Forest Vegetation Simulator (FVS) is used widely for forest management in the US, and its scope and complexity continue to...

A Mixed Model for Real-Time, Interactive Simulation of a Cable Passing Through Several Pulleys

NASA Astrophysics Data System (ADS)

García-Fernández, Ignacio; Pla-Castells, Marta; Martínez-Durá, Rafael J.

2007-09-01

A model of a cable and pulleys is presented that can be used in Real Time Computer Graphics applications. The model is formulated by the coupling of a damped spring and a variable coefficient wave equation, and can be integrated in more complex mechanical models of lift systems, such as cranes, elevators, etc. with a high degree of interactivity.

MX Siting Investigation. Water Resources Program, Technical Summary Report. Volume II.

DTIC Science & Technology

1981-11-30

Selected digital computer techniques for groundwater resource evaluation, Illinois State Water Survey, Bulletin No. 55. Robinson, B. P., Thordarson , W., and...34, American Geophysical Union Transactions, v. 16. Thordarson , W., and Robinson, B. P., 1971, Wells and springs in California and Nevada within 100... Thordarson , W., 1975, Hydrogeologic and hydro- chemical framework, south-central Great Basin, Nevada- * California, with special reference to the Nevada

Description and Evaluation of Numerical Groundwater Flow Models for the Edwards Aquifer, South-Central Texas

USGS Publications Warehouse

Lindgren, Richard J.; Taylor, Charles J.; Houston, Natalie A.

2009-01-01

A substantial number of public water system wells in south-central Texas withdraw groundwater from the karstic, highly productive Edwards aquifer. However, the use of numerical groundwater flow models to aid in the delineation of contributing areas for public water system wells in the Edwards aquifer is problematic because of the complex hydrogeologic framework and the presence of conduit-dominated flow paths in the aquifer. The U.S. Geological Survey, in cooperation with the Texas Commission on Environmental Quality, evaluated six published numerical groundwater flow models (all deterministic) that have been developed for the Edwards aquifer San Antonio segment or Barton Springs segment, or both. This report describes the models developed and evaluates each with respect to accessibility and ease of use, range of conditions simulated, accuracy of simulations, agreement with dye-tracer tests, and limitations of the models. These models are (1) GWSIM model of the San Antonio segment, a FORTRAN computer-model code that pre-dates the development of MODFLOW; (2) MODFLOW conduit-flow model of San Antonio and Barton Springs segments; (3) MODFLOW diffuse-flow model of San Antonio and Barton Springs segments; (4) MODFLOW Groundwater Availability Modeling [GAM] model of the Barton Springs segment; (5) MODFLOW recalibrated GAM model of the Barton Springs segment; and (6) MODFLOW-DCM (dual conductivity model) conduit model of the Barton Springs segment. The GWSIM model code is not commercially available, is limited in its application to the San Antonio segment of the Edwards aquifer, and lacks the ability of MODFLOW to easily incorporate newly developed processes and packages to better simulate hydrologic processes. MODFLOW is a widely used and tested code for numerical modeling of groundwater flow, is well documented, and is in the public domain. These attributes make MODFLOW a preferred code with regard to accessibility and ease of use. The MODFLOW conduit-flow model incorporates improvements over previous models by using (1) a user-friendly interface, (2) updated computer codes (MODFLOW-96 and MODFLOW-2000), (3) a finer grid resolution, (4) less-restrictive boundary conditions, (5) an improved discretization of hydraulic conductivity, (6) more accurate estimates of pumping stresses, (7) a long transient simulation period (54 years, 1947-2000), and (8) a refined representation of high-permeability zones or conduits. All of the models except the MODFLOW-DCM conduit model have limitations resulting from the use of Darcy's law to simulate groundwater flow in a karst aquifer system where non-Darcian, turbulent flow might actually dominate. The MODFLOW-DCM conduit model is an improvement in the ability to simulate karst-like flow conditions in conjunction with porous-media-type matrix flow. However, the MODFLOW-DCM conduit model has had limited application and testing and currently (2008) lacks commercially available pre- and post-processors. The MODFLOW conduit-flow and diffuse-flow Edwards aquifer models are limited by the lack of calibration for the northern part of the Barton Springs segment (Travis County) and their reliance on the use of the calibrated hydraulic conductivity and storativity values from the calibrated Barton Springs segment GAM model. The major limitation of the Barton Springs segment GAM and recalibrated GAM models is that they were calibrated to match measured water levels and springflows for a restrictive range of hydrologic conditions, with each model having different hydraulic conductivity and storativity values appropriate to the hydrologic conditions that were simulated. The need for two different sets of hydraulic conductivity and storativity values increases the uncertainty associated with the accuracy of either set of values, illustrates the non-uniqueness of the model solution, and probably most importantly demonstrates the limitations of using a one-layer model to represent the heterogeneous hydrostratigraph

Classical Mechanics Experiments using Wiimotes

NASA Astrophysics Data System (ADS)

Lopez, Alexander; Ochoa, Romulo

2010-02-01

The Wii, a video game console, is a very popular device. Although computationally it is not a powerful machine by today's standards, to a physics educator the controllers are its most important components. The Wiimote (or remote) controller contains a three-axis accelerometer, an infrared detector, and Bluetooth connectivity at a relatively low price. Thanks to available open source code, such as GlovePie, any PC or Laptop with Bluetooth capability can detect the information sent out by the Wiimote. We present experiments that use two or three Wiimotes simultaneously to measure the variable accelerations in two mass systems interacting via springs. Normal modes are determined from the data obtained. Masses and spring constants are varied to analyze their impact on the accelerations of the systems. We present the results of our experiments and compare them with those predicted using Lagrangian mechanics. )

Dynamic responses of railroad car models to vertical and lateral rail inputs

NASA Technical Reports Server (NTRS)

Sewall, J. L.; Parrish, R. V.; Durling, B. J.

1971-01-01

Simplified dynamic models were applied in a study of vibration in a high-speed railroad car. The mathematical models used were a four-degree-of-freedom model for vertical responses to vertical rail inputs and a ten-degree-of-freedom model for lateral response to lateral or rolling (cross-level) inputs from the rails. Elastic properties of the passenger car body were represented by bending and torsion of a uniform beam. Rail-to-car (truck) suspensions were modeled as spring-mass-dashpot oscillators. Lateral spring nonlinearities approximating certain complicated truck mechanisms were introduced. The models were excited by displacement and, in some cases, velocity inputs from the rails by both deterministic (including sinusoidal) and random input functions. Results were obtained both in the frequency and time domains. Solutions in the time domain for the lateral model were obtained for a wide variety of transient and random inputs generated on-line by an analog computer. Variations in one of the damping properties of the lateral car suspension gave large fluctuations in response over a range of car speeds for a given input. This damping coefficient was significant in reducing lateral car responses that were higher for nonlinear springs for three different inputs.

Evaluation of nonlinear structural dynamic responses using a fast-running spring-mass formulation

NASA Astrophysics Data System (ADS)

Benjamin, A. S.; Altman, B. S.; Gruda, J. D.

In today's world, accurate finite-element simulations of large nonlinear systems may require meshes composed of hundreds of thousands of degrees of freedom. Even with today's fast computers and the promise of ever-faster ones in the future, central processing unit (CPU) expenditures for such problems could be measured in days. Many contemporary engineering problems, such as those found in risk assessment, probabilistic structural analysis, and structural design optimization, cannot tolerate the cost or turnaround time for such CPU-intensive analyses, because these applications require a large number of cases to be run with different inputs. For many risk assessment applications, analysts would prefer running times to be measurable in minutes. There is therefore a need for approximation methods which can solve such problems far more efficiently than the very detailed methods and yet maintain an acceptable degree of accuracy. For this purpose, we have been working on two methods of approximation: neural networks and spring-mass models. This paper presents our work and results to date for spring-mass modeling and analysis, since we are further along in this area than in the neural network formulation. It describes the physical and numerical models contained in a code we developed called STRESS, which stands for 'Spring-mass Transient Response Evaluation for structural Systems'. The paper also presents results for a demonstration problem, and compares these with results obtained for the same problem using PRONTO3D, a state-of-the-art finite element code which was also developed at Sandia.

Assessment of the forecast skill of spring onset in the NMME experiment

NASA Astrophysics Data System (ADS)

Carrillo, C. M.; Ault, T.

2017-12-01

This study assesses the predictability of spring onset using an index of its interannual variability. We use the North American Multi-Model Ensemble (NMME) experiment to assess this predictability. The input dataset to compute spring onset index, SI-x, were treated with a daily joint bias correction (JBC) approach, and the SI-x outputs were post-processed using three ensemble model output statistic (EMOS) approaches—logistic regression, Gaussian Ensemble Dressing, and non-homogeneous Gaussian regression. These EMOS approaches quantify the effect of training period length and ensemble size on forecast skill. The highest range of predictability for the timing spring onset is from 10 to 60 days, and it is located along a narrow band between 35° to 45°N in the US. Using rank probability scores based on quantiles (q), a forecast threshold (q) of 0.5 provides a range of predictability that falls into two categories 10-40 and 40-60 days, which seems to represent the effect of the intra-seasonal scale. Using higher thresholds (q=0.6 and 0.7) predictability shows lower range with values around 10-30 days. The post-processing work using JBC improves the predictability skill by 13% from uncorrected results. Using EMOS, a significant positive change in the skill score is noted in regions where the skill with JBC shows evidence of improvement. The consensus of these techniques shows that regions of better predictability can be expanded.

Characterization and analysis of temporal and spatial variations in habitat and macroinvertebrate community structure, Fountain Creek basin, Colorado Springs and vicinity, Colorado, 1998-2001

USGS Publications Warehouse

Bruce, James F.

2002-01-01

The Fountain Creek Basin in and around Colorado Springs, Colorado, is affected by various land- and water-use activities. Biological, hydrological, water-quality, and land-use data were collected at 10 sites in the Fountain Creek Basin from April 1998 through April 2001 to provide a baseline characterization of macroinvertebrate communities and habitat conditions for comparison in subsequent studies; and to assess variation in macroinvertebrate community structure relative to habitat quality. Analysis of variance results indicated that instream and riparian variables were not affected by season, but significant differences were found among sites. Nine metrics were used to describe and evaluate macroinvertebrate community structure. Statistical analysis indicated that for six of the nine metrics, significant variability occurred between spring and fall seasons for 60 percent of the sites. Cluster analysis (unweighted pair group method average) using macroinvertebrate presence-absence data showed a well-defined separation between spring and fall samples. Six of the nine metrics had significant spatial variation. Cluster analysis using Sorenson?s Coefficient of Community values computed from macroinvertebrate density (number of organisms per square meter) data showed that macroinvertebrate community structure was more similar among tributary sites than main-stem sites. Canonical correspondence analysis identified a substrate particle-size gradient from site-specific species-abundance data and environmental correlates that decreased the 10 sites to 5 site clusters and their associated taxa.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harris, S.; Gross, R.; Goble, W

The safety integrity level (SIL) of equipment used in safety instrumented functions is determined by the average probability of failure on demand (PFDavg) computed at the time of periodic inspection and maintenance, i.e., the time of proof testing. The computation of PFDavg is generally based solely on predictions or estimates of the assumed constant failure rate of the equipment. However, PFDavg is also affected by maintenance actions (or lack thereof) taken by the end user. This paper shows how maintenance actions can affect the PFDavg of spring operated pressure relief valves (SOPRV) and how these maintenance actions may be accountedmore » for in the computation of the PFDavg metric. The method provides a means for quantifying the effects of changes in maintenance practices and shows how these changes impact plant safety.« less

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 39: The role of computer networks in aerospace engineering

NASA Technical Reports Server (NTRS)

Bishop, Ann P.; Pinelli, Thomas E.

1994-01-01

This paper presents selected results from an empirical investigation into the use of computer networks in aerospace engineering. Such networks allow aerospace engineers to communicate with people and access remote resources through electronic mail, file transfer, and remote log-in. The study drew its subjects from private sector, government and academic organizations in the U.S. aerospace industry. Data presented here were gathered in a mail survey, conducted in Spring 1993, that was distributed to aerospace engineers performing a wide variety of jobs. Results from the mail survey provide a snapshot of the current use of computer networks in the aerospace industry, suggest factors associated with the use of networks, and identify perceived impacts of networks on aerospace engineering work and communication.

Using Computer Simulation for Neurolab 2 Mission Planning

NASA Technical Reports Server (NTRS)

Sanders, Betty M.

1997-01-01

This paper presents an overview of the procedure used in the creation of a computer simulation video generated by the Graphics Research and Analysis Facility at NASA/Johnson Space Center. The simulation was preceded by an analysis of anthropometric characteristics of crew members and workspace requirements for 13 experiments to be conducted on Neurolab 2 which is dedicated to neuroscience and behavioral research. Neurolab 2 is being carried out as a partnership among national domestic research institutes and international space agencies. The video is a tour of the Spacelab module as it will be configured for STS-90, scheduled for launch in the spring of 1998, and identifies experiments that can be conducted in parallel during that mission. Therefore, this paper will also address methods for using computer modeling to facilitate the mission planning activity.

Surveys of water velocities in the vicinity of the discharge-release gates of Salamonie Lake Dam, northeastern Indiana, spring and winter 1998

USGS Publications Warehouse

Morlock, Scott E.; Stewart, James A.

2000-01-01

An acoustic Doppler current profiler (ADCP) mounted on a boat was used to collect velocity and depth data and to compute positions of the velocity and depth data relative to the boat track. A global positioning system (GPS) was used to collect earth-referenced position data, and a GPS base station receiver was used to improve the accuracy of the earth-referenced position data. The earth-referenced position data were used to transform the ADCP-computed positions (which were relative to boat tracks) to positions referenced to a point on the spillway tower.

Genetic Interaction Score (S-Score) Calculation, Clustering, and Visualization of Genetic Interaction Profiles for Yeast.

PubMed

Roguev, Assen; Ryan, Colm J; Xu, Jiewei; Colson, Isabelle; Hartsuiker, Edgar; Krogan, Nevan

2018-02-01

This protocol describes computational analysis of genetic interaction screens, ranging from data capture (plate imaging) to downstream analyses. Plate imaging approaches using both digital camera and office flatbed scanners are included, along with a protocol for the extraction of colony size measurements from the resulting images. A commonly used genetic interaction scoring method, calculation of the S-score, is discussed. These methods require minimal computer skills, but some familiarity with MATLAB and Linux/Unix is a plus. Finally, an outline for using clustering and visualization software for analysis of resulting data sets is provided. © 2018 Cold Spring Harbor Laboratory Press.

Designing and Implementing a Computational Methods Course for Upper-level Undergraduates and Postgraduates in Atmospheric and Oceanic Sciences

NASA Astrophysics Data System (ADS)

Nelson, E.; L'Ecuyer, T. S.; Douglas, A.; Hansen, Z.

2017-12-01

In the modern computing age, scientists must utilize a wide variety of skills to carry out scientific research. Programming, including a focus on collaborative development, has become more prevalent in both academic and professional career paths. Faculty in the Department of Atmospheric and Oceanic Sciences at the University of Wisconsin—Madison recognized this need and recently approved a new course offering for undergraduates and postgraduates in computational methods that was first held in Spring 2017. Three programming languages were covered in the inaugural course semester and development themes such as modularization, data wrangling, and conceptual code models were woven into all of the sections. In this presentation, we will share successes and challenges in developing a research project-focused computational course that leverages hands-on computer laboratory learning and open-sourced course content. Improvements and changes in future iterations of the course based on the first offering will also be discussed.

Geologic, hydrologic, and geochemical identification of flow paths in the Edwards Aquifer, northeastern Bexar and southern Comal Counties, Texas

USGS Publications Warehouse

Otero, Cassi L.

2007-01-01

The U.S. Geological Survey, in cooperation with the San Antonio Water System, conducted a 4-year study during 2002?06 to identify major flow paths in the Edwards aquifer in northeastern Bexar and southern Comal Counties (study area). In the study area, faulting directs ground water into three hypothesized flow paths that move water, generally, from the southwest to the northeast. These flow paths are identified as the southern Comal flow path, the central Comal flow path, and the northern Comal flow path. Statistical correlations between water levels for six observation wells and between the water levels and discharges from Comal Springs and Hueco Springs yielded evidence for the hypothesized flow paths. Strong linear correlations were evident between the datasets from wells and springs within the same flow path and the datasets from wells in areas where flow between flow paths was suspected. Geochemical data (major ions, stable isotopes, sulfur hexafluoride, and tritium and helium) were used in graphical analyses to obtain evidence of the flow path from which wells or springs derive water. Major-ion geochemistry in samples from selected wells and springs showed relatively little variation. Samples from the southern Comal flow path were characterized by relatively high sulfate and chloride concentrations, possibly indicating that the water in the flow path was mixing with small amounts of saline water from the freshwater/saline-water transition zone. Samples from the central Comal flow path yielded the most varied major-ion geochemistry of the three hypothesized flow paths. Central Comal flow path samples were characterized, in general, by high calcium concentrations and low magnesium concentrations. Samples from the northern Comal flow path were characterized by relatively low sulfate and chloride concentrations and high magnesium concentrations. The high magnesium concentrations characteristic of northern Comal flow path samples from the recharge zone in Comal County might indicate that water from the Trinity aquifer is entering the Edwards aquifer in the subsurface. A graph of the relation between the stable isotopes deuterium and delta-18 oxygen showed that, except for samples collected following an unusually intense rain storm, there was not much variation in stable isotope values among the flow paths. In the study area deuterium ranged from -36.00 to -20.89 per mil and delta-18 oxygen ranged from -6.03 to -3.70 per mil. Excluding samples collected following the intense rain storm, the deuterium range in the study area was -33.00 to -20.89 per mil and the delta-18 oxygen range was -4.60 to -3.70 per mil. Two ground-water age-dating techniques, sulfur hexafluoride concentrations and tritium/helium-3 isotope ratios, were used to compute apparent ages (time since recharge occurred) of water samples collected in the study area. In general, the apparent ages computed by the two methods do not seem to indicate direction of flow. Apparent ages computed for water samples in northeastern Bexar and southern Comal Counties do not vary greatly except for some very young water in the recharge zone in central Comal County.

Prediction of suspended-sediment concentrations at selected sites in the Fountain Creek watershed, Colorado, 2008-09

USGS Publications Warehouse

Stogner, Sr., Robert W.; Nelson, Jonathan M.; McDonald, Richard R.; Kinzel, Paul J.; Mau, David P.

2013-01-01

In 2008, the U.S. Geological Survey (USGS), in cooperation with Pikes Peak Area Council of Governments, Colorado Water Conservation Board, Colorado Springs City Engineering, and the Lower Arkansas Valley Water Conservancy District, began a small-scale pilot study to evaluate the effectiveness of the use of a computational model of streamflow and suspended-sediment transport for predicting suspended-sediment concentrations and loads in the Fountain Creek watershed in Colorado. Increased erosion and sedimentation damage have been identified by the Fountain Creek Watershed Plan as key problems within the watershed. A recommendation in the Fountain Creek Watershed plan for management of the basin is to establish measurable criteria to determine if progress in reducing erosion and sedimentation damage is being made. The major objective of this study was to test a computational method to predict local suspended-sediment loads at two sites with different geomorphic characteristics in order to evaluate the feasibility of using such an approach to predict local suspended-sediment loads throughout the entire watershed. Detailed topographic surveys, particle-size data, and suspended-sediment samples were collected at two gaged sites: Monument Creek above Woodmen Road at Colorado Springs, Colorado (USGS gage 07103970), and Sand Creek above mouth at Colorado Springs, Colorado (USGS gage 07105600). These data were used to construct three-dimensional computational models of relatively short channel reaches at each site. The streamflow component of these models predicted a spatially distributed field of water-surface elevation, water velocity, and bed shear stress for a range of stream discharges. Using the model predictions, along with measured particle sizes, the sediment-transport component of the model predicted the suspended-sediment concentration throughout the reach of interest. These computed concentrations were used with predicted flow patterns and channel morphology to determine fluxes of suspended sediment for the median particle size and for the measured range of particle sizes in the channel. Three different techniques were investigated for making the suspended-sediment predictions; these techniques have varying degrees of reliance on measured data and also have greatly differing degrees of complexity. Based on these data, the calibrated Rouse method provided the best balance between accuracy and both computational and data collection costs; the presence of substantial washload was the primary factor in eliminating the simpler and the more complex techniques. Based on this work, using the selected technique at additional sites in the watershed to determine relative loads and source areas appears plausible. However, to ensure that the methodology presented in this report yields reasonable results at other selected sites in the basin, it is necessary to collect additional verification data sets at those locations.

The Effects of Using Google SketchUp on the Mental Rotation Skills of Eighth Grade Students

ERIC Educational Resources Information Center

Erkoc, Mehmet Fatih; Gecu, Zeynep; Erkoc, Cigdem

2013-01-01

The aim of this study is to investigate the effectiveness of Google SketchUp, which is a computer aided design (CAD) software, on the Mental Rotation Skills of eighth grade students. For this purpose, in the spring semester of the 2011-2012 academic year, a treatment was conducted with 62 students comprised of 8A and 8B classes in the GSD…

Working Notes of the 1990 Spring Symposium on Automated Abduction

DTIC Science & Technology

1990-09-27

possibilities for abstracting the leaf nodes in using apprenticeship learning techniques. In LTCAI.E the proof tree. Morgan Kaufmann, 1987. A detailed...ibm.com Abstract planation process and compute particular operational A major limitation of explanation-based learn - descriptions of the target...for the learning that would be difficult or impos- 3n educated, somewhat abstract guess at why the pro- sible using abduction. I position is likely to

Wind tunnel balance system for determination of wind-induced vibrations of a rigid shuttle model in the launch configuration

NASA Technical Reports Server (NTRS)

1971-01-01

A wind tunnel balance system was designed to determine the wind-induced vibrations of a space shuttle model. The balance utilizes a flexible sting mounting in conjunction with a geometrically scaled rigid model. Bending and torsional displacements are determined through strain-gauge-instrumented spring bar mechanisms. The natural frequency of the string-model system can be varied continuously throughout the expected scaled frequency range of the shuttle vehicle while a test is in progress by the use of moveable riders on the spring bar mechanism. Through the use of a frequency analyzer, the output can be used to determine troublesome vibrational frequencies. A dimensional analysis of the wind-induced vibration problem is also presented which suggests a test procedure. In addition a computer program for analytical studies of the forced vibration problem is presented.

Using the Scroll Wheel on a Wireless Mouse as a Motion Sensor

NASA Astrophysics Data System (ADS)

Taylor, Richard S.; Wilson, William R.

2010-12-01

Since its inception in the mid-80s, the computer mouse has undergone several design changes. As the mouse has evolved, physicists have found new ways to utilize it as a motion sensor. For example, the rollers in a mechanical mouse have been used as pulleys to study the motion of a magnet moving through a copper tube as a quantitative demonstration of Lenz's law and to study mechanical oscillators (e.g., mass-spring system and compound pendulum).1-3 Additionally, the optical system in an optical mouse has been used to study a mechanical oscillator (e.g., mass-spring system).4 The argument for using a mouse as a motion sensor has been and continues to be availability and cost. This paper continues this tradition by detailing the use of the scroll wheel on a wireless mouse as a motion sensor.

Analysis and experimental evaluation of a Stewart platform-based force/torque sensor

NASA Technical Reports Server (NTRS)

Nguyen, Charles C.; Antrazi, Sami S.

1992-01-01

The kinematic analysis and experimentation of a force/torque sensor whose design is based on the mechanism of the Stewart Platform are discussed. Besides being used for measurement of forces/torques, the sensor also serves as a compliant platform which provides passive compliance during a robotic assembly task. It consists of two platforms, the upper compliant platform (UCP) and the lower compliant platform (LCP), coupled together through six spring-loaded pistons whose length variations are measured by six linear voltage differential transformers (LVDT) mounted along the pistons. Solutions to the forward and inverse kinematics of the force sensor are derived. Based on the known spring constant and the piston length changes, forces/torques applied to the LCP gripper are computed using vector algebra. Results of experiments conducted to evaluate the sensing capability of the force sensor are reported and discussed.

Quantification of effect of sequential posteromedial release on flexion and extension gaps: a computer-assisted study in cadaveric knees.

PubMed

Mullaji, Arun; Sharma, Amit; Marawar, Satyajit; Kanna, Raj

2009-08-01

A novel sequence of posteromedial release consistent with surgical technique of total knee arthroplasty was performed in 15 cadaveric knees. Medial and lateral flexion and extension gaps were measured after each step of the release using a computed tomography-free computer navigation system. A spring-loaded distractor and a manual distractor were used to distract the joint. Posterior cruciate ligament release increased flexion more than extension gap; deep medial collateral ligament release had a negligible effect; semimembranosus release increased the flexion gap medially; reduction osteotomy increased medial flexion and extension gaps; superficial medial collateral ligament release increased medial joint gap more in flexion and caused severe instability. This sequence of release led to incremental and differential effects on flexion-extension gaps and has implications in correcting varus deformity.

A dynamic spar numerical model for passive shape change

NASA Astrophysics Data System (ADS)

Calogero, J. P.; Frecker, M. I.; Hasnain, Z.; Hubbard, J. E., Jr.

2016-10-01

A three-dimensional constraint-driven dynamic rigid-link numerical model of a flapping wing structure with compliant joints (CJs) called the dynamic spar numerical model is introduced and implemented. CJs are modeled as spherical joints with distributed mass and spring-dampers with coupled nonlinear spring and damping coefficients, which models compliant mechanisms spatially distributed in the structure while greatly reducing computation time compared to a finite element model. The constraints are established, followed by the formulation of a state model used in conjunction with a forward time integrator, an experiment to verify a rigid-link assumption and determine a flapping angle function, and finally several example runs. Modeling the CJs as coupled bi-linear springs shows the wing is able to flex more during upstroke than downstroke. Coupling the spring stiffnesses allows an angular deformation about one axis to induce an angular deformation about another axis, where the magnitude is proportional to the coupling term. Modeling both the leading edge and diagonal spars shows that the diagonal spar changes the kinematics of the leading edge spar verses only considering the leading edge spar, causing much larger axial rotations in the leading edge spar. The kinematics are very sensitive to CJ location, where moving the CJ toward the wing root causes a stronger response, and adding multiple CJs on the leading edge spar with a CJ on the diagonal spar allows the wing to deform with larger magnitude in all directions. This model lays a framework for a tool which can be used to understand flapping wing flight.

A Centennial Tribute, 1906-2006: History of U.S. Geological Survey Streamgaging Activities for the Suwannee River at White Springs, Florida

USGS Publications Warehouse

Verdi, Richard Jay; Tomlinson, Stewart A.

2009-01-01

For centuries, the banks of the Suwannee River at White Springs were considered a sacred ground where people sought refuge in its 'healing waters'. Many believed that the mineral-enriched waters cured illnesses. The U.S. Geological Survey began continuous streamgaging activities at White Springs, Florida, in 1906 after an increase in congressional appropriations and rapid town development due to growing tourism and residential population. In 1906, streamgage data was a once-per-day gage reading that were handwritten in a water-level booklet by a local observer with discharge measurements taken every 6 to 8 weeks by a hydrographer. In 2006, real-time data were recorded at 1-hour increments and transmitted to U.S. Geological Survey computer networks using the Geostationary Operational Environmental Satellite, thus enabling the general public to access readings within minutes of the actual measurement. Additional data and measurements are taken and made available for high or low flows that occur during significant floods and droughts. The gage at White Springs has recorded several historic hydrologic events that affected the Suwannee River and surrounding areas. Major droughts include those during 1931-35, 1949-57, and 1998-2002. Severe floods occurred in 1948, 1973, and 2004. On April 10, 1973, the discharge was 38,100 cubic feet per second, which is the highest recorded discharge for the period of record. A flood of this magnitude is expected at a recurrence interval of about once every 200 to 500 years.

Calculation of the Relative Chemical Stabilities of Proteins as a Function of Temperature and Redox Chemistry in a Hot Spring

PubMed Central

Dick, Jeffrey M.; Shock, Everett L.

2011-01-01

Uncovering the chemical and physical links between natural environments and microbial communities is becoming increasingly amenable owing to geochemical observations and metagenomic sequencing. At the hot spring known as Bison Pool in Yellowstone National Park, the cooling of the water in the outflow channel is associated with an increase in oxidation potential estimated from multiple field-based measurements. Representative groups of proteins whose sequences were derived from metagenomic data also exhibit an increase in average oxidation state of carbon in the protein molecules with distance from the hot-spring source. The energetic requirements of reactions to form selected proteins used in the model were computed using amino-acid group additivity for the standard molal thermodynamic properties of the proteins, and the relative chemical stabilities of the proteins were investigated by varying temperature, pH and oxidation state, expressed as activity of dissolved hydrogen. The relative stabilities of the proteins were found to track the locations of the sampling sites when the calculations included a function for hydrogen activity that increases with temperature and is higher, or more reducing, than values consistent with measurements of dissolved oxygen, sulfide and oxidation-reduction potential in the field. These findings imply that spatial patterns in the amino acid compositions of proteins can be linked, through energetics of overall chemical reactions representing the formation of the proteins, to the environmental conditions at this hot spring, even if microbial cells maintain considerably different internal conditions. Further applications of the thermodynamic calculations are possible for other natural microbial ecosystems. PMID:21853048

Dynamics of aircraft antiskid braking systems. [conducted at the Langley aircraft landing loads and traction facility

NASA Technical Reports Server (NTRS)

Tanner, J. A.; Stubbs, S. M.; Dreher, R. C.; Smith, E. G.

1982-01-01

A computer study was performed to assess the accuracy of three brake pressure-torque mathematical models. The investigation utilized one main gear wheel, brake, and tire assembly of a McDonnell Douglas DC-9 series 10 airplane. The investigation indicates that the performance of aircraft antiskid braking systems is strongly influenced by tire characteristics, dynamic response of the antiskid control valve, and pressure-torque response of the brake. The computer study employed an average torque error criterion to assess the accuracy of the models. The results indicate that a variable nonlinear spring with hysteresis memory function models the pressure-torque response of the brake more accurately than currently used models.

SEEK: A FORTRAN optimization program using a feasible directions gradient search

NASA Technical Reports Server (NTRS)

Savage, M.

1995-01-01

This report describes the use of computer program 'SEEK' which works in conjunction with two user-written subroutines and an input data file to perform an optimization procedure on a user's problem. The optimization method uses a modified feasible directions gradient technique. SEEK is written in ANSI standard Fortran 77, has an object size of about 46K bytes, and can be used on a personal computer running DOS. This report describes the use of the program and discusses the optimizing method. The program use is illustrated with four example problems: a bushing design, a helical coil spring design, a gear mesh design, and a two-parameter Weibull life-reliability curve fit.

Development of a realistic stress analysis for fatigue analysis of notched composite laminates

NASA Technical Reports Server (NTRS)

Humphreys, E. A.; Rosen, B. W.

1979-01-01

A finite element stress analysis which consists of a membrane and interlaminar shear spring analysis was developed. This approach was utilized in order to model physically realistic failure mechanisms while maintaining a high degree of computational economy. The accuracy of the stress analysis predictions is verified through comparisons with other solutions to the composite laminate edge effect problem. The stress analysis model was incorporated into an existing fatigue analysis methodology and the entire procedure computerized. A fatigue analysis is performed upon a square laminated composite plate with a circular central hole. A complete description and users guide for the computer code FLAC (Fatigue of Laminated Composites) is included as an appendix.

Testing and validating the CERES-wheat (Crop Estimation through Resource and Environment Synthesis-wheat) model in diverse environments

NASA Technical Reports Server (NTRS)

Otter-Nacke, S.; Godwin, D. C.; Ritchie, J. T.

1986-01-01

CERES-Wheat is a computer simulation model of the growth, development, and yield of spring and winter wheat. It was designed to be used in any location throughout the world where wheat can be grown. The model is written in Fortran 77, operates on a daily time stop, and runs on a range of computer systems from microcomputers to mainframes. Two versions of the model were developed: one, CERES-Wheat, assumes nitrogen to be nonlimiting; in the other, CERES-Wheat-N, the effects of nitrogen deficiency are simulated. The report provides the comparisons of simulations and measurements of about 350 wheat data sets collected from throughout the world.

Electromechanical actuator for the tongs of a servomanipulator

DOEpatents

Martin, H. Lee; Killough, Stephen M.

1986-01-01

Computer-augmented electromechanical system is provided for controlling the tongs of a servomanipulator. The mechanical tongs are motor-driven through the remote slave arm of the manipulator, and the motor control current is supplied by a position sensor which senses the position of a spring-loaded trigger in the master arm handle on the manipulator. The actuator for the tongs provides the operator with artificial force reflection in a unilateral force-force control loop.

Computer-aided drug design: the next 20 years

NASA Astrophysics Data System (ADS)

Van Drie, John H.

2007-10-01

This perspectives article has been taken from a talk the author gave at the symposium in honor of Yvonne C. Martin's retirement, held at the American Chemical Society spring meeting in Chicago on March 25, 2007. The talk was intended as a somewhat lighthearted attempt to gaze into the future; inevitably, in print, things will come across more seriously than was intended. As we all know—the past is rarely predictive of the future.

Anthropomorphic robot for recognition of objects

NASA Astrophysics Data System (ADS)

Ginzburg, Vera M.

1999-08-01

Heated debates were taking place a few decades ago between the proponents of digital and analog methods in information. Technology have resulted in unequivocal triumph of the former. However, some serious technological problems confronting the world civilization on the threshold of the new millennium, such as Y2K and computer network vulnerability, probably spring from this one-sided approach. Dire consequences of problems of this kind can be alleviated through learning from the nature.

International Conference on Artificial Immune Systems (1st) ICARIS 2002, held on 9, 10, and 11 September 2002

DTIC Science & Technology

2002-03-07

Michalewicz, Eds., Evolutionary Computation 1: Basic Algorithms and Operators, Institute of Physics, Bristol (UK), 2000. [3] David A. Van Veldhuizen ...2000. [4] Carlos A. Coello Coello, David A. Van Veldhuizen , and Gary B. Lamont, Evolutionary Algorithms for Solving Multi-Objective Problems, Kluwer...Academic Publishers, 233 Spring St., New York, NY 10013, 2002. [5] David A. Van Veldhuizen , Multiobjective Evolution- ary Algorithms: Classifications

Ny-Alesund Geodetic Observatory

NASA Technical Reports Server (NTRS)

Sieber, Moritz

2013-01-01

In 2012 the 20-m telescope at Ny-Alesund, Svalbard, operated by the Norwegian Mapping Authority (NMA), took part in 163 out of 168 scheduled sessions of the IVS program. Since spring, all data was transferred by network, and the receiver monitoring computer was replaced by a bus-coupler. In autumn, the NMA received building permission for a new observatory from the Governor of Svalbard. The bidding process and first construction work for the infrastructure will start in 2013.

The Resource. Spring 2000

DTIC Science & Technology

2000-01-01

One Is Best? 8 Meet Your Customer Assistance Team 20 ERDC MSRC Computer Systems Are Gems 25 ERDC MSRC Contributions to SC99 15 2 ERDC MSRC The... Customer Assistance Center (CAC) for several years and has achieved a reputation as an onsite Kerberos and portable batch system (PBS) expert within...Laboratory to send its mobile unit to obtain blood donations for a young woman in the Vicksburg community who was in desperate need of blood in January

Real-Time, Wide Area Dispatch of Mobil Tank Trucks

DTIC Science & Technology

1987-01-01

human dispatchers it assists. Using CAD, Mobil has substantially re- duced costs and staff while improving customer service. I n the spring of 1985, a...process by establishing the Mobil order response center (MORC). To use MORC, the customer dials a toll-free number, available 24 hours a day, seven...MATS Figwe 3: Mobil light products order and dispatch information flow. Customers call an audio re- sponse computer system named MORC ( Mobil order

Development of technique for three-dimensional visualization of grain boundaries by white X-ray microbeam

NASA Astrophysics Data System (ADS)

Kajiwara, K.; Shobu, T.; Toyokawa, H.; Sato, M.

2014-04-01

A technique for three-dimensional visualization of grain boundaries was developed at BL28B2 at SPring-8. The technique uses white X-ray microbeam diffraction and a rotating slit. Three-dimensional images of small silicon single crystals filled in a plastic tube were successfully obtained using this technique for demonstration purposes. The images were consistent with those obtained by X-ray computed tomography.

Analytic and Computational Studies on Micro-Propulsion and Micro-detonics

DTIC Science & Technology

2006-08-22

Professor. • Dr. Aslan Kasimov, PostDoctoral Research Associate (Stewart), May 2004- June 2005. • Mr. Aslan Kasimov, Graduate Student (Stewart...Short continuing as his Ph.D. advisor. 2. Research completed with AFOSR support (a ) Reseach summary: Prof. D.S. Stewart (1) A.R. Kasimov and D.S...Theory of Instability and Nonlinear Evolution of Self-Sustained Detonation Waves”. Ph.D., Spring 2004. • Mr. Dave Kessler, Graduate Student (Short

Elastic coupling of limb joints enables faster bipedal walking

PubMed Central

Dean, J.C.; Kuo, A.D.

2008-01-01

The passive dynamics of bipedal limbs alone are sufficient to produce a walking motion, without need for control. Humans augment these dynamics with muscles, actively coordinated to produce stable and economical walking. Present robots using passive dynamics walk much slower, perhaps because they lack elastic muscles that couple the joints. Elastic properties are well known to enhance running gaits, but their effect on walking has yet to be explored. Here we use a computational model of dynamic walking to show that elastic joint coupling can help to coordinate faster walking. In walking powered by trailing leg push-off, the model's speed is normally limited by a swing leg that moves too slowly to avoid stumbling. A uni-articular spring about the knee allows faster but uneconomical walking. A combination of uni-articular hip and knee springs can speed the legs for improved speed and economy, but not without the swing foot scuffing the ground. Bi-articular springs coupling the hips and knees can yield high economy and good ground clearance similar to humans. An important parameter is the knee-to-hip moment arm that greatly affects the existence and stability of gaits, and when selected appropriately can allow for a wide range of speeds. Elastic joint coupling may contribute to the economy and stability of human gait. PMID:18957360

Conceptualization of Karstic Aquifer with Multiple Outlets Using a Dual Porosity Model.

PubMed

Hosseini, Seiyed Mossa; Ataie-Ashtiani, Behzad

2017-07-01

In this study, two conceptual models, the classic reservoir (CR) model and exchange reservoirs model embedded by dual porosity approach (DPR) are developed for simulation of karst aquifer functioning drained by multiple outlets. The performances of two developed models are demonstrated at a less developed karstic aquifer with three spring outlets located in Zagros Mountain in the south-west of Iran using 22-years of daily data. During the surface recharge, a production function based on water mass balance is implemented for computing the time series of surface recharge to the karst formations. The efficiency of both models has been assessed for simulation of daily spring discharge during the recession and also surface recharge periods. Results indicate that both CR and DPR models are capable of simulating the ordinates of spring hydrographs which drainage less developed karstic aquifer. However, the goodness of fit criteria indicates outperformance of DPR model for simulation of total hydrograph ordinates. In addition, the DPR model is capable of quantifying hydraulic properties of two hydrologically connected overlapping continua conduits network and fissure matrix which lays important foundations for the mining operation and water resource management whereas homogeneous model representations of the karstic subsurface (e.g., the CR) do not work accurately in the karstic environment. © 2017, National Ground Water Association.

Lighting Condition Analysis for Mars' Moon Phobos

NASA Technical Reports Server (NTRS)

Li, Zu Qun; de Carufel, Guy; Crues, Edwin Z.; Bielski, Paul

2016-01-01

This study used high fidelity computer simulation to investigate the lighting conditions, specifically the solar radiation flux over the surface, on Phobos. Ephemeris data from the Jet Propulsion Laboratory (JPL) DE405 model was used to model the state of the Sun, Earth, Moon, and Mars. An occultation model was developed to simulate Phobos' self-shadowing and its solar eclipses by Mars. The propagated Phobos state was compared with data from JPL's Horizon system to ensure the accuracy of the result. Results for Phobos lighting conditions over one Martian year are presented, which include the duration of solar eclipses, average solar radiation intensity, surface exposure time, and radiant exposure for both sun tracking and fixed solar arrays. The results show that: Phobos' solar eclipse time varies throughout the Martian year, with longer eclipse durations during the Martian northern spring and fall seasons and no eclipses during the Martian northern summer and winter seasons; solar radiation intensity is close to minimum in late spring and close to maximum in late fall; exposure time per orbit is relatively constant over the surface during the spring and fall but varies with latitude during the summer and winter; and Sun tracking solar arrays generate more energy than a fixed solar array. A usage example of the result is also present in this paper to demonstrate the utility.

Endoscopic add-on stiffness probe for real-time soft surface characterisation in MIS.

PubMed

Faragasso, A; Stilli, A; Bimbo, J; Noh, Y; Liu, H; Nanayakkara, T; Dasgupta, P; Wurdemann, H A; Althoefer, K

2014-01-01

This paper explores a novel stiffness sensor which is mounted on the tip of a laparoscopic camera. The proposed device is able to compute stiffness when interacting with soft surfaces. The sensor can be used in Minimally Invasive Surgery, for instance, to localise tumor tissue which commonly has a higher stiffness when compared to healthy tissue. The purely mechanical sensor structure utilizes the functionality of an endoscopic camera to the maximum by visually analyzing the behavior of trackers within the field of view. Two pairs of spheres (used as easily identifiable features in the camera images) are connected to two springs with known but different spring constants. Four individual indenters attached to the spheres are used to palpate the surface. During palpation, the spheres move linearly towards the objective lens (i.e. the distance between lens and spheres is changing) resulting in variations of their diameters in the camera images. Relating the measured diameters to the different spring constants, a developed mathematical model is able to determine the surface stiffness in real-time. Tests were performed using a surgical endoscope to palpate silicon phantoms presenting different stiffness. Results show that the accuracy of the sensing system developed increases with the softness of the examined tissue.

TALEs from a spring--superelasticity of Tal effector protein structures.

PubMed

Flechsig, Holger

2014-01-01

Transcription activator-like effectors (TALEs) are DNA-related proteins that recognise and bind specific target sequences to manipulate gene expression. Recently determined crystal structures show that their common architecture reveals a superhelical overall structure that may undergo drastic conformational changes. To establish a link between structure and dynamics in TALE proteins we have employed coarse-grained elastic-network modelling of currently available structural data and implemented a force-probe setup that allowed us to investigate their mechanical behaviour in computer experiments. Based on the measured force-extension curves we conclude that TALEs exhibit superelastic dynamical properties allowing for large-scale global conformational changes along their helical axis, which represents the soft direction in such proteins. For moderate external forcing the TALE models behave like linear springs, obeying Hooke's law, and the investigated structures can be characterised and compared by a corresponding spring constant. We show that conformational flexibility underlying the large-scale motions is not homogeneously distributed over the TALE structure, but instead soft spot residues around which strain is accumulated and which turn out to represent key agents in the transmission of conformational motions are identified. They correspond to the RVD loop residues that have been experimentally determined to play an eminent role in the binding process of target DNA.

TALEs from a Spring – Superelasticity of Tal Effector Protein Structures

PubMed Central

Flechsig, Holger

2014-01-01

Transcription activator-like effectors (TALEs) are DNA-related proteins that recognise and bind specific target sequences to manipulate gene expression. Recently determined crystal structures show that their common architecture reveals a superhelical overall structure that may undergo drastic conformational changes. To establish a link between structure and dynamics in TALE proteins we have employed coarse-grained elastic-network modelling of currently available structural data and implemented a force-probe setup that allowed us to investigate their mechanical behaviour in computer experiments. Based on the measured force-extension curves we conclude that TALEs exhibit superelastic dynamical properties allowing for large-scale global conformational changes along their helical axis, which represents the soft direction in such proteins. For moderate external forcing the TALE models behave like linear springs, obeying Hooke's law, and the investigated structures can be characterised and compared by a corresponding spring constant. We show that conformational flexibility underlying the large-scale motions is not homogeneously distributed over the TALE structure, but instead soft spot residues around which strain is accumulated and which turn out to represent key agents in the transmission of conformational motions are identified. They correspond to the RVD loop residues that have been experimentally determined to play an eminent role in the binding process of target DNA. PMID:25313859

Groundwater flow cycling between a submarine spring and an inland fresh water spring

USGS Publications Warehouse

Davis, J. Hal; Verdi, Richard

2014-01-01

Spring Creek Springs and Wakulla Springs are large first magnitude springs that derive water from the Upper Floridan Aquifer. The submarine Spring Creek Springs are located in a marine estuary and Wakulla Springs are located 18 km inland. Wakulla Springs has had a consistent increase in flow from the 1930s to the present. This increase is probably due to the rising sea level, which puts additional pressure head on the submarine Spring Creek Springs, reducing its fresh water flow and increasing flows in Wakulla Springs. To improve understanding of the complex relations between these springs, flow and salinity data were collected from June 25, 2007 to June 30, 2010. The flow in Spring Creek Springs was most sensitive to rainfall and salt water intrusion, and the flow in Wakulla Springs was most sensitive to rainfall and the flow in Spring Creek Springs. Flows from the springs were found to be connected, and composed of three repeating phases in a karst spring flow cycle: Phase 1 occurred during low rainfall periods and was characterized by salt water backflow into the Spring Creek Springs caves. The higher density salt water blocked fresh water flow and resulted in a higher equivalent fresh water head in Spring Creek Springs than in Wakulla Springs. The blocked fresh water was diverted to Wakulla Springs, approximately doubling its flow. Phase 2 occurred when heavy rainfall resulted in temporarily high creek flows to nearby sinkholes that purged the salt water from the Spring Creek Springs caves. Phase 3 occurred after streams returned to base flow. The Spring Creek Springs caves retained a lower equivalent fresh water head than Wakulla Springs, causing them to flow large amounts of fresh water while Wakulla Springs flow was reduced by about half.

Neural networks as a control methodology

NASA Technical Reports Server (NTRS)

Mccullough, Claire L.

1990-01-01

While conventional computers must be programmed in a logical fashion by a person who thoroughly understands the task to be performed, the motivation behind neural networks is to develop machines which can train themselves to perform tasks, using available information about desired system behavior and learning from experience. There are three goals of this fellowship program: (1) to evaluate various neural net methods and generate computer software to implement those deemed most promising on a personal computer equipped with Matlab; (2) to evaluate methods currently in the professional literature for system control using neural nets to choose those most applicable to control of flexible structures; and (3) to apply the control strategies chosen in (2) to a computer simulation of a test article, the Control Structures Interaction Suitcase Demonstrator, which is a portable system consisting of a small flexible beam driven by a torque motor and mounted on springs tuned to the first flexible mode of the beam. Results of each are discussed.

Multibody dynamical modeling for spacecraft docking process with spring-damper buffering device: A new validation approach

NASA Astrophysics Data System (ADS)

Daneshjou, Kamran; Alibakhshi, Reza

2018-01-01

In the current manuscript, the process of spacecraft docking, as one of the main risky operations in an on-orbit servicing mission, is modeled based on unconstrained multibody dynamics. The spring-damper buffering device is utilized here in the docking probe-cone system for micro-satellites. Owing to the impact occurs inevitably during docking process and the motion characteristics of multibody systems are remarkably affected by this phenomenon, a continuous contact force model needs to be considered. Spring-damper buffering device, keeping the spacecraft stable in an orbit when impact occurs, connects a base (cylinder) inserted in the chaser satellite and the end of docking probe. Furthermore, by considering a revolute joint equipped with torsional shock absorber, between base and chaser satellite, the docking probe can experience both translational and rotational motions simultaneously. Although spacecraft docking process accompanied by the buffering mechanisms may be modeled by constrained multibody dynamics, this paper deals with a simple and efficient formulation to eliminate the surplus generalized coordinates and solve the impact docking problem based on unconstrained Lagrangian mechanics. By an example problem, first, model verification is accomplished by comparing the computed results with those recently reported in the literature. Second, according to a new alternative validation approach, which is based on constrained multibody problem, the accuracy of presented model can be also evaluated. This proposed verification approach can be applied to indirectly solve the constrained multibody problems by minimum required effort. The time history of impact force, the influence of system flexibility and physical interaction between shock absorber and penetration depth caused by impact are the issues followed in this paper. Third, the MATLAB/SIMULINK multibody dynamic analysis software will be applied to build impact docking model to validate computed results and then, investigate the trajectories of both satellites to take place the successful capture process.

Reconnaissance of surface-water resources in the Kobuk River basin, Alaska, 1979-80

USGS Publications Warehouse

Childers, J.M.; Kernodle, D.R.

1983-01-01

Surface water data were collected at selected sites in the Kobuk River Basin in northwest Alaska in August 1979 and April 1980. In August 1979, frequent heavy rains caused abnormally high flows in the basin; unit runoff values, computed from discharge measurements at 25 sites, ranged from 0.08 to 12.2 cu ft/sec/sq mi. Mean unit runoff for August computed from 13 years of record at a stream gaging station on the Kobuk River ranged from 1 to 3 cu ft/sec/sq mi. Unit runoff computed from discharge measurements made at eight sites in April 1980 ranged from 0 to 0.30 cubic feet per second per square mile. These values are in reasonable agreement with those derived from the record at the gaging station. High-water marks of maximum evident floods and evidence of ice-affected flooding were found at near bankfull stages at 17 sites on the Kobuk River and its tributaries. Computed unit runoff for the maximum evident floods generally decreases with increasing drainage area. Unit runoff ranges from about 50 to 75 cu ft/sec/sq mi for drainage areas < 1,000 sq mi to < 25 cu ft/sec/sq mi for larger areas. Field determinations were made of water temperature, pH, alkalinity, dissolved-oxygen concentration, and specific conductance, and discharge was measured at about 40 stream sites and one spring. Water samples for laboratory analysis of dissolved inorganic constituents and biological samples were collected in August 1979. Water quality data indicate that the surface waters would be acceptable for most uses; they are a calcium bicarbonate type having dissolved-solids concentrations between 50 and 140 milligm/liter. The pristine nature of the waters is also indicated by the overall diversity and composition of its benthic invertebrate community. A more highly mineralized (about 550 milligm/liter dissolved solids) sodium bicarbonate water flows from Reed River Hot Spring. (USGS)

Groundwater flow cycling between a submarine spring and an inland fresh water spring.

PubMed

Davis, J Hal; Verdi, Richard

2014-01-01

Spring Creek Springs and Wakulla Springs are large first magnitude springs that derive water from the Upper Floridan Aquifer. The submarine Spring Creek Springs are located in a marine estuary and Wakulla Springs are located 18 km inland. Wakulla Springs has had a consistent increase in flow from the 1930s to the present. This increase is probably due to the rising sea level, which puts additional pressure head on the submarine Spring Creek Springs, reducing its fresh water flow and increasing flows in Wakulla Springs. To improve understanding of the complex relations between these springs, flow and salinity data were collected from June 25, 2007 to June 30, 2010. The flow in Spring Creek Springs was most sensitive to rainfall and salt water intrusion, and the flow in Wakulla Springs was most sensitive to rainfall and the flow in Spring Creek Springs. Flows from the springs were found to be connected, and composed of three repeating phases in a karst spring flow cycle: Phase 1 occurred during low rainfall periods and was characterized by salt water backflow into the Spring Creek Springs caves. The higher density salt water blocked fresh water flow and resulted in a higher equivalent fresh water head in Spring Creek Springs than in Wakulla Springs. The blocked fresh water was diverted to Wakulla Springs, approximately doubling its flow. Phase 2 occurred when heavy rainfall resulted in temporarily high creek flows to nearby sinkholes that purged the salt water from the Spring Creek Springs caves. Phase 3 occurred after streams returned to base flow. The Spring Creek Springs caves retained a lower equivalent fresh water head than Wakulla Springs, causing them to flow large amounts of fresh water while Wakulla Springs flow was reduced by about half. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

FIRST Quantum-(1980)-Computing DISCOVERY in Siegel-Rosen-Feynman-...A.-I. Neural-Networks: Artificial(ANN)/Biological(BNN) and Siegel FIRST Semantic-Web and Siegel FIRST ``Page''-``Brin'' ``PageRank'' PRE-Google Search-Engines!!!

NASA Astrophysics Data System (ADS)

Rosen, Charles; Siegel, Edward Carl-Ludwig; Feynman, Richard; Wunderman, Irwin; Smith, Adolph; Marinov, Vesco; Goldman, Jacob; Brine, Sergey; Poge, Larry; Schmidt, Erich; Young, Frederic; Goates-Bulmer, William-Steven; Lewis-Tsurakov-Altshuler, Thomas-Valerie-Genot; Ibm/Exxon Collaboration; Google/Uw Collaboration; Microsoft/Amazon Collaboration; Oracle/Sun Collaboration; Ostp/Dod/Dia/Nsa/W.-F./Boa/Ubs/Ub Collaboration

2013-03-01

Belew[Finding Out About, Cambridge(2000)] and separately full-decade pre-Page/Brin/Google FIRST Siegel-Rosen(Machine-Intelligence/Atherton)-Feynman-Smith-Marinov(Guzik Enterprises/Exxon-Enterprises/A.-I./Santa Clara)-Wunderman(H.-P.) [IBM Conf. on Computers and Mathematics, Stanford(1986); APS Mtgs.(1980s): Palo Alto/Santa Clara/San Francisco/...(1980s) MRS Spring-Mtgs.(1980s): Palo Alto/San Jose/San Francisco/...(1980-1992) FIRST quantum-computing via Bose-Einstein quantum-statistics(BEQS) Bose-Einstein CONDENSATION (BEC) in artificial-intelligence(A-I) artificial neural-networks(A-N-N) and biological neural-networks(B-N-N) and Siegel[J. Noncrystalline-Solids 40, 453(1980); Symp. on Fractals..., MRS Fall-Mtg., Boston(1989)-5-papers; Symp. on Scaling..., (1990); Symp. on Transport in Geometric-Constraint (1990)

A self-adaptive-grid method with application to airfoil flow

NASA Technical Reports Server (NTRS)

Nakahashi, K.; Deiwert, G. S.

1985-01-01

A self-adaptive-grid method is described that is suitable for multidimensional steady and unsteady computations. Based on variational principles, a spring analogy is used to redistribute grid points in an optimal sense to reduce the overall solution error. User-specified parameters, denoting both maximum and minimum permissible grid spacings, are used to define the all-important constants, thereby minimizing the empiricism and making the method self-adaptive. Operator splitting and one-sided controls for orthogonality and smoothness are used to make the method practical, robust, and efficient. Examples are included for both steady and unsteady viscous flow computations about airfoils in two dimensions, as well as for a steady inviscid flow computation and a one-dimensional case. These examples illustrate the precise control the user has with the self-adaptive method and demonstrate a significant improvement in accuracy and quality of the solutions.

CFD Modeling of Free-Piston Stirling Engines

NASA Technical Reports Server (NTRS)

Ibrahim, Mounir B.; Zhang, Zhi-Guo; Tew, Roy C., Jr.; Gedeon, David; Simon, Terrence W.

2001-01-01

NASA Glenn Research Center (GRC) is funding Cleveland State University (CSU) to develop a reliable Computational Fluid Dynamics (CFD) code that can predict engine performance with the goal of significant improvements in accuracy when compared to one-dimensional (1-D) design code predictions. The funding also includes conducting code validation experiments at both the University of Minnesota (UMN) and CSU. In this paper a brief description of the work-in-progress is provided in the two areas (CFD and Experiments). Also, previous test results are compared with computational data obtained using (1) a 2-D CFD code obtained from Dr. Georg Scheuerer and further developed at CSU and (2) a multidimensional commercial code CFD-ACE+. The test data and computational results are for (1) a gas spring and (2) a single piston/cylinder with attached annular heat exchanger. The comparisons among the codes are discussed. The paper also discusses plans for conducting code validation experiments at CSU and UMN.

Modeling of rolling element bearing mechanics. Computer program user's manual

NASA Technical Reports Server (NTRS)

Greenhill, Lyn M.; Merchant, David H.

1994-01-01

This report provides the user's manual for the Rolling Element Bearing Analysis System (REBANS) analysis code which determines the quasistatic response to external loads or displacement of three types of high-speed rolling element bearings: angular contact ball bearings, duplex angular contact ball bearings, and cylindrical roller bearings. The model includes the defects of bearing ring and support structure flexibility. It is comprised of two main programs: the Preprocessor for Bearing Analysis (PREBAN) which creates the input files for the main analysis program, and Flexibility Enhanced Rolling Element Bearing Analysis (FEREBA), the main analysis program. This report addresses input instructions for and features of the computer codes. A companion report addresses the theoretical basis for the computer codes. REBANS extends the capabilities of the SHABERTH (Shaft and Bearing Thermal Analysis) code to include race and housing flexibility, including such effects as dead band and preload springs.

Workstations for people with disabilities: an example of a virtual reality approach

PubMed Central

Budziszewski, Paweł; Grabowski, Andrzej; Milanowicz, Marcin; Jankowski, Jarosław

2016-01-01

This article describes a method of adapting workstations for workers with motion disability using computer simulation and virtual reality (VR) techniques. A workstation for grinding spring faces was used as an example. It was adjusted for two people with a disabled right upper extremity. The study had two stages. In the first, a computer human model with a visualization of maximal arm reach and preferred workspace was used to develop a preliminary modification of a virtual workstation. In the second stage, an immersive VR environment was used to assess the virtual workstation and to add further modifications. All modifications were assessed by measuring the efficiency of work and the number of movements involved. The results of the study showed that a computer simulation could be used to determine whether a worker with a disability could access all important areas of a workstation and to propose necessary modifications. PMID:26651540

A user's guide to the SUDAN computer program for determining the vibration modes of structural systems. Ph.D. Thesis - Case Western Reserve Univ., Jun. 1963

NASA Technical Reports Server (NTRS)

Kvaternik, R. G.; Durling, B. J.

1978-01-01

The use of the SUDAN computer program for analyzing structural systems for their natural modes and frequencies of vibration is described. SUDAN is intended for structures which can be represented as an equivalent system of beam, spring, and rigid-body substructures. User-written constraint equations are used to analytically join the mass and stiffness matrices of the substructures to form the mass and stiffness matrices of the complete structure from which all the frequencies and modes of the system are determined. The SUDAN program can treat the case in which both the mass and stiffness matrices of the coupled system may be singular simultaneously. A general description of the FORTRAN IV program is given, the computer hardware and software specifications are indicated, and the input required by the program is described.

Computational methods for the control of distributed parameter systems

NASA Technical Reports Server (NTRS)

Burns, J. A.; Cliff, E. M.; Powers, R. K.

1985-01-01

It is shown that care must be taken to ensure that finite dimensional approximations of distributed parameter systems preserve important system properties (i.e., controllability, observability, stabilizability, detectability, etc.). It is noted that, if the particular scheme used to construct the finite dimensional model does not take into account these system properties, the model may not be suitable for control design and analysis. These ideas are illustrated by a simple example, i.e., a cable-spring-mass system.

A Study of Wall Jets and Tangentially Blown Wings

DTIC Science & Technology

1981-07-01

Blowing coefficient C Chapman’constant CFF Far field constant CL Lift coefficient SCp Pressure coefficient D Reduced exit height E Normalized stagnation...that the wave interactiop zone there is (6(4/ 3 ). 74 C3471A/jos Oil % Rockwell International Science Cenier SC5055.21FR TABLE 4 - PARAMETRIC SUIMMY OF...34Analysis of Embedded Shock Waves Calculated by Relaxation Methods," Proc. Computational Fluid Dynamics Conference, Palm Springs, Calif., July 19-20, 1973, pp

An estimator for the standard deviation of a natural frequency. I.

NASA Technical Reports Server (NTRS)

Schiff, A. J.; Bogdanoff, J. L.

1971-01-01

A brief review of mean-square approximate systems is given. The case in which the masses are deterministic is considered first in the derivation of an estimator for the upper bound of the standard deviation of a natural frequency. Two examples presented include a two-degree-of-freedom system and a case in which the disorder in the springs is perfectly correlated. For purposes of comparison, a Monte Carlo simulation was done on a digital computer.

Proceedings of the NITINOL Heat Engine Conference, 26-27 September 1978, Silver Spring, Maryland

DTIC Science & Technology

1978-09-27

allowed us to design, build, and test various engine designs, while exploring advanced concepts with computer modeling of motor dynamics and heat exchange ...exclude the effects of element geometi y and other material parameters which affect the heat exchange rate and kinetics of the SRP. 5-3...is in Rference 8. 13. In the present work we exclude the effects of element geometry and other material parameters which affect the heat exchange

Materials Research of Novel Organic Piezoelectric/Ferroelectric Compounds at a H.S.I

DTIC Science & Technology

2015-07-06

analysis 4. http://wavefun.com 5. MOPAC2012, James J. P. Stewart, Stewart Computational Chemistry, Colorado Springs, CO, USA, HTTP://OpenMOPAC. net ... petri dish of mineral oil (to prevent electrical arcing) ripples in the mineral oil are clearly visible when a voltage is applied to the sample. We...acid. It does not appear to be ferroelectric. However, it is piezoelectric. When placed in a petri dish of mineral oil (to prevent electrical arcing

Neurale Netwerken en Radarsystemen (Neural Networks and Radar Systems)

DTIC Science & Technology

1989-08-01

general issues in cognitive science", Parallel distributed processing, Vol 1: Foundations, Rumelhart et al. 1986 pp 110-146 THO rapport Pagina 151 36 D.E...34Neural networks (part 2)",Expert Focus, IEEE Expert, Spring 1988. 61 J.A. Anderson, " Cognitive and Psychological Computations with Neural Models", IEEE...Pagina 154 69 David H. Ackley, Geoffrey E. Hinton and Terrence J. Sejnowski, "A Learning Algorithm for Boltzmann machines", cognitive science 9, 147-169

SPring-8 beamline control system.

PubMed

Ohata, T; Konishi, H; Kimura, H; Furukawa, Y; Tamasaku, K; Nakatani, T; Tanabe, T; Matsumoto, N; Ishii, M; Ishikawa, T

1998-05-01

The SPring-8 beamline control system is now taking part in the control of the insertion device (ID), front end, beam transportation channel and all interlock systems of the beamline: it will supply a highly standardized environment of apparatus control for collaborative researchers. In particular, ID operation is very important in a third-generation synchrotron light source facility. It is also very important to consider the security system because the ID is part of the storage ring and is therefore governed by the synchrotron ring control system. The progress of computer networking systems and the technology of security control require the development of a highly flexible control system. An interlock system that is independent of the control system has increased the reliability. For the beamline control system the so-called standard model concept has been adopted. VME-bus (VME) is used as the front-end control system and a UNIX workstation as the operator console. CPU boards of the VME-bus are RISC processor-based board computers operated by a LynxOS-based HP-RT real-time operating system. The workstation and the VME are linked to each other by a network, and form the distributed system. The HP 9000/700 series with HP-UX and the HP 9000/743rt series with HP-RT are used. All the controllable apparatus may be operated from any workstation.

A Real-Time Imaging System for Stereo Atomic Microscopy at SPring-8's BL25SU

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsushita, Tomohiro; Guo, Fang Zhun; Muro, Takayuki

2007-01-19

We have developed a real-time photoelectron angular distribution (PEAD) and Auger-electron angular distribution (AEAD) imaging system at SPring-8 BL25SU, Japan. In addition, a real-time imaging system for circular dichroism (CD) studies of PEAD/AEAD has been newly developed. Two PEAD images recorded with left- and right-circularly polarized light can be regarded as a stereo image of the atomic arrangement. A two-dimensional display type mirror analyzer (DIANA) has been installed at the beamline, making it possible to record PEAD/AEAD patterns with an acceptance angle of {+-}60 deg. in real-time. The twin-helical undulators at BL25SU enable helicity switching of the circularly polarized lightmore » at 10Hz, 1Hz or 0.1Hz. In order to realize real-time measurements of the CD of the PEAD/AEAD, the CCD camera must be synchronized to the switching frequency. The VME computer that controls the ID is connected to the measurement computer with two BNC cables, and the helicity information is sent using TTL signals. For maximum flexibility, rather than using a hardware shutter synchronizing with the TTL signal we have developed software to synchronize the CCD shutter with the TTL signal. We have succeeded in synchronizing the CCD camera in both the 1Hz and 0.1Hz modes.« less

MPPhys—A many-particle simulation package for computational physics education

NASA Astrophysics Data System (ADS)

Müller, Thomas

2014-03-01

In a first course to classical mechanics elementary physical processes like elastic two-body collisions, the mass-spring model, or the gravitational two-body problem are discussed in detail. The continuation to many-body systems, however, is deferred to graduate courses although the underlying equations of motion are essentially the same and although there is a strong motivation for high-school students in particular because of the use of particle systems in computer games. The missing link between the simple and the more complex problem is a basic introduction to solve the equations of motion numerically which could be illustrated, however, by means of the Euler method. The many-particle physics simulation package MPPhys offers a platform to experiment with simple particle simulations. The aim is to give a principle idea how to implement many-particle simulations and how simulation and visualization can be combined for interactive visual explorations. Catalogue identifier: AERR_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AERR_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 111327 No. of bytes in distributed program, including test data, etc.: 608411 Distribution format: tar.gz Programming language: C++, OpenGL, GLSL, OpenCL. Computer: Linux and Windows platforms with OpenGL support. Operating system: Linux and Windows. RAM: Source Code 4.5 MB Complete package 242 MB Classification: 14, 16.9. External routines: OpenGL, OpenCL Nature of problem: Integrate N-body simulations, mass-spring models Solution method: Numerical integration of N-body-simulations, 3D-Rendering via OpenGL. Running time: Problem dependent

Estimation of survival of adult Florida manatees in the Crystal River, at Blue Spring, and on the Atlantic Coast

USGS Publications Warehouse

O'Shea, Thomas J.; Langtimm, Catherine A.; O'Shea, Thomas J.; Ackerman, B.B.; Percival, H. Franklin

1995-01-01

We applied Cormack-Jolly-Seber open population models to manatee (Trichechus manatus latirostris) photo-identification databases to estimate adult survival probabilities. The computer programs JOLLY and RECAPCO were used to estimate survival of 677 individuals in three study areas: Crystal River (winters 1977-78 to 1990-91), Blue Spring (winters 1977-78 to 1990-91), and the Atlantic Coast (winters 1984-85 to 1990-91). We also estimated annual survival from observations of 111 manatees tagged for studies with radiotelemetry. Survival estimated from observations with telemetry had broader confidence intervals than survival estimated with the Cormack-Jolly-Seber models. Annual probabilities of capture based on photo-identification records were generally high. The mean annual adult survival estimated from sighting-resighting records was 0.959-0.962 in the Crystal River and 0.936-0.948 at Blue Spring and may be high enough to permit population growth, given the values of other life-history parameters. On the Atlantic Coast, the estimated annual adult survival (range of means = 0.877-0.885) may signify a declining population. However, for several reasons, interpretation of data from the latter study group should be tempered with caution. Adult survivorship seems to be constant with age in all three study groups. No strong differences were apparent between adult survival ofmales and females in the Crystal River or at Blue Spring; the basis of significant differences between sexes on the Atlantic Coast is unclear. Future research into estimating survival with photo-identification and the Cormack-Jolly-Seber models should be vigorously pursued. Estimates of annual survival can provide an additional indication of Florida manatee population status with a stronger statistical basis than aerial counts and carcass totals.

Low-temperature geothermal potential of the Ojo Caliente warm springs area, northern New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vuataz, F.D.; Stix, J.; Goff, F.

1984-05-01

A detailed geochemical investigation of 17 waters (thermal and cold, mineralized and dilute) was performed in the Ojo Caliente-La Madera area. Two types of thermomineral waters have separate and distinctive geologic, geochemical, and geothermal characteristics. The water from Ojo Caliente Resort emerges with temperatures less than or equal to 54/sup 0/C from a Precambrian metarhyolite. Its chemistry, typically Na-HCO/sub 3/, has a total mineralization of 3600 mg/l. Isotopic studies have shown that the thermal water emerges from the springs and a hot well without significant mixing with the cold shallow aquifer of the valley alluvium. However, the cold aquifer adjacentmore » to the resort does contain varying amounts of thermal water that originates from the warm spring system. Geothermometry calculations indicate that the thermal water may be as hot as 85/sup 0/C at depth before its ascent toward surface. Thermodynamic computations on the reaction states of numerous mineral phases suggest that the thermal water will not cause major scaling problems if the hot water is utilized for direct-use geothermal applications. By means of a network of very shallow holes, temperature and electrical conductivity anomalies have been found elsewhere in the valley around Ojo Caliente, and resistivity soundings have confirmed the presence of a plume of thermal water entering the shallow aquifer. The group of lukewarm springs around La Madera, with temperatures less than or equal to 29/sup 0/C, chemical type of NaCaMg-HCO/sub 3/Cl and with a total mineralization less than or equal to 1500 mg/l behaves as a different system without any apparent relation to the Ojo Caliente system. Its temperature at depth is not believed to exceed 35 to 40/sup 0/C.« less

Changes in running mechanics and spring-mass behavior induced by a mountain ultra-marathon race.

PubMed

Morin, J B; Tomazin, K; Edouard, P; Millet, G Y

2011-04-07

Changes in running mechanics and spring-mass behavior due to fatigue induced by a mountain ultra-marathon race (MUM, 166km, total positive and negative elevation of 9500m) were studied in 18 ultra-marathon runners. Mechanical measurements were undertaken pre- and 3h post-MUM at 12km h(-1) on a 7m long pressure walkway: contact (t(c)), aerial (t(a)) times, step frequency (f), and running velocity (v) were sampled and averaged over 5-8 steps. From these variables, spring-mass parameters of peak vertical ground reaction force (F(max)), vertical downward displacement of the center of mass (Δz), leg length change (ΔL), vertical (k(vert)) and leg (k(leg)) stiffness were computed. After the MUM, there was a significant increase in f (5.9±5.5%; P<0.001) associated with reduced t(a) (-18.5±17.4%; P<0.001) with no change in t(c), and a significant decrease in both Δz and F(max) (-11.6±10.5 and -6.3±7.3%, respectively; P<0.001). k(vert) increased by 5.6±11.7% (P=0.053), and k(leg) remained unchanged. These results show that 3h post-MUM, subjects ran with a reduced vertical oscillation of their spring-mass system. This is consistent with (i) previous studies concerning muscular structure/function impairment in running and (ii) the hypothesis that these changes in the running pattern could be associated with lower overall impact (especially during the braking phase) supported by the locomotor system at each step, potentially leading to reduced pain during running. Copyright © 2011 Elsevier Ltd. All rights reserved.

On foundations of discrete element analysis of contact in diarthrodial joints.

PubMed

Volokh, K Y; Chao, E Y S; Armand, M

2007-06-01

Information about the stress distribution on contact surfaces of adjacent bones is indispensable for analysis of arthritis, bone fracture and remodeling. Numerical solution of the contact problem based on the classical approaches of solid mechanics is sophisticated and time-consuming. However, the solution can be essentially simplified on the following physical grounds. The bone contact surfaces are covered with a layer of articular cartilage, which is a soft tissue as compared to the hard bone. The latter allows ignoring the bone compliance in analysis of the contact problem, i.e. rigid bones are considered to interact through a compliant cartilage. Moreover, cartilage shear stresses and strains can be ignored because of the negligible friction between contacting cartilage layers. Thus, the cartilage can be approximated by a set of unilateral compressive springs normal to the bone surface. The forces in the springs can be computed from the equilibrium equations iteratively accounting for the changing contact area. This is the essence of the discrete element analysis (DEA). Despite the success in applications of DEA to various bone contact problems, its classical formulation required experimental validation because the springs approximating the cartilage were assumed linear while the real articular cartilage exhibited non-linear mechanical response in reported tests. Recent experimental results of Ateshian and his co-workers allow for revisiting the classical DEA formulation and establishing the limits of its applicability. In the present work, it is shown that the linear spring model is remarkably valid within a wide range of large deformations of the cartilage. It is also shown how to extend the classical DEA to the case of strong nonlinearity if necessary.

Steerable Hopping Six-Legged Robot

NASA Technical Reports Server (NTRS)

Younse, Paulo; Aghazarian, Hrand

2010-01-01

The figure depicts selected aspects of a six-legged robot that moves by hopping and that can be steered in the sense that it can be launched into a hop in a controllable direction. This is a prototype of hopping robots being developed for use in scientific exploration of rough terrain on remote planets that have surface gravitation less than that of Earth. Hopping robots could also be used on Earth, albeit at diminished hopping distances associated with the greater Earth gravitation. The upper end of each leg is connected through two universal joints to an upper and a lower hexagonal frame, such that the tilt of the leg depends on the relative position of the two frames. Two non-back-driveable worm-gear motor drives are used to control the relative position of the two frames along two axes 120 apart, thereby controlling the common tilt of all six legs and thereby, further, controlling the direction of hopping. Each leg includes an upper and a lower aluminum frame segment with a joint between them. A fiberglass spring, connected via hinges to both segments, is used to store hopping energy prior to launch into a hop and to cushion the landing at the end of the hop. A cable for loading the spring is run into each leg through the center of the universal joints and then down along the center lines of the segments to the lower end of the leg. A central spool actuated by a motor with a harmonic drive and an electromagnetic clutch winds in all six cables to compress all six springs (thereby also flexing all six legs) simultaneously. To ensure that all the legs push off and land in the same direction, timing- belt pulley drives are attached to the leg segments, restricting the flexing and extension of all six legs to a common linear motion. In preparation for a hop, the spool can be driven to load the spring legs by an amount corresponding to a desired hop distance within range. The amount of compression can be computed from the reading of a shaft-angle encoder that indicates the amount by which the spool has been turned. When the robot is ready to hop, the electromagnetic clutch disengages the motor from the spool, thus releasing the cable restraints on the springs and allowing the springs to extend all six legs simultaneously.

Hydrogeology and ground-water-flow simulation of the Cave Springs area, Hixson, Tennessee

USGS Publications Warehouse

Haugh, Connor J.

2002-01-01

The ground-water resource in the Cave Springs area is used by the Hixson Utility District as a water supply and is one of the more heavily stressed in the Valley and Ridge Physiographic Province. In 1999, ground-water withdrawals by the Hixson Utility District averaged about 6.4 million gallons per day (Mgal/d) from two pumping centers. The Hixson Utility District has historically withdrawn about 5.8 Mgal/d from wells at Cave Springs. In 1995 to meet increasing demand, an additional well field was developed at Walkers Corner, located about 3 miles northeast of Cave Springs. From 1995 through 2000, pumping from the first production well at Walkers Corner averaged about 1.8 Mgal/d. A second production well at Walkers Corner was approved for use in 2000. Hixson Utility District alternates the use of the two production wells at Walkers Corner except when drought conditions occur when they are used simultaneously. The second production well increased the capacity of the well field by an additional 2 Mgal/d. The aquifer framework in the study area consists of dense Paleozoic carbonate rocks with secondary permeability that are mantled by thick residual clay-rich regolith in most of the area and by coarse-grained alluvium in the valley of North Chickamauga Creek. Cave Springs, one of the largest springs in Tennessee, derives its flow from conduits in a carbonate rock (karst) aquifer. Production wells at Cave Springs draw water from these conduits. Production wells at Walkers Corner primarily draw water from gravel zones in the regolith near the top of rock. Transmissivities estimated from hydraulic tests conducted across the Cave Springs area span a range from 240 to 900,000 feet squared per day (ft2/d) with a median value of 5,200 ft2/d. Recharge to the aquifer occurs from direct infiltration of precipitation and from losing streams. Most recharge occurs during the winter and spring months. Computer modeling was used to provide a better understanding of the ground-water-flow system and to simulate the effects of additional ground-water withdrawals. A numerical ground-water-flow model of the ground-water system was constructed and calibrated using MODFLOW 2000. Modeling results indicate that losing streams along the base of the Cumberland Plateau escarpment at the western edge of the study area are an important source of recharge to the ground-water system, supplying about 50 percent of the recharge to the study area. Direct infiltration of precipitation accounts for the remaining recharge to the study area. In 1999, ground-water withdrawals of 6.4 Mgal/d [9.9 cubic feet per second (ft3/s)] equaled about 11 percent of the total simulated ground-water recharge. The remaining ground-water recharge discharges to rivers (48 percent, 41.1 ft3/s), springs (19 percent, 16.8 ft3/s), and Chickamauga Lake (22 percent, 19.0 ft3/s). Drawdown at the Walkers Corner well field in 2000 was about 33 feet at the center of a cone of depression that is elongated along strike. If additional pumping at Walkers Corner increases withdrawals by 2 Mgal/d, simulated drawdown at the Walkers Corner well field increases to about 60 feet and simulated ground-water discharges decrease by amounts of 1.0 ft3/s to Chickamauga Lake, 0.8 ft3/s to North Chickamauga Creek, 0.5 ft3/s to Lick Branch-Rogers Spring drainage, 0.5 ft3/s to Poe Branch, and 0.2 ft3/s to Cave Springs.

Hydrology, Water Quality, and Aquatic Communities of Selected Springs in the St. Johns River Water Management District, Florida

USGS Publications Warehouse

Walsh, Stephen J.; Knowles, Leel; Katz, Brian G.; Strom, Douglas G.

2009-01-01

Hydrologic, physicochemical, and aquatic community data were collected and compiled by the U.S. Geological Survey for selected springs within the St. Johns River Water Management District from January 2004 to October 2007. Nine springs were included in this study: Alexander, Apopka, Bugg, De Leon, Gemini, Green, Rock, Silver Glen, and Wekiwa. Urban lands increased in Alexander, Apopka, De Leon, Gemini, Green, and Wekiwa springsheds between 1973 and 2004, accompanied by a loss of forested and/or agricultural lands in most springsheds. Forested cover increased and open surface waters and wetlands decreased in the Bugg and Rock springsheds. Although rainfall did not change significantly over time in each springshed, spring discharge decreased significantly in De Leon, Fern Hammock, Rock, Silver, and Wekiwa Springs. Nitrate concentrations increased significantly with time in Apopka, Fern Hammock, Gemini Springs run, and Juniper Springs, and decreased significantly in Alexander Spring, Bugg Spring run, Rock Springs, and Wekiwa Springs. Phosphorus increased significantly with time in Juniper Springs and decreased significantly in Apopka, De Leon, Rock, Silver Glen, and Wekiwa Springs. Benthic macroinvertebrate communities ranged from relatively low diversity assemblages (Green Spring) to assemblages with high taxonomic richness, diversity, and dominance (Rock and De Leon Springs). Shannon-Wiener diversity index averages among samples pooled by spring were lowest for Apopka Spring and greatest for Rock, Bugg, and Silver Glen Springs. Mean Stream Condition Index for pooled samples per spring was lowest for De Leon and Gemini Springs and highest for Rock and Wekiwa Springs. Mean percentages of very tolerant taxa were lowest for Alexander Spring and highest for Bugg and Green Springs. Fish community richness was lowest for Green Spring, and greatest for Alexander Spring run and Silver Glen Springs. Forty five fish species representing 35 genera and 23 families were collected or observed from all springs in this study. Samples were dominated by centrarchids, cyprinids, fundulids, atherinopsids, and poeciliids.

Geographic Information Systems Methods for Determining Drainage-Basin Areas, Stream-Buffered Areas, Stream Length, and Land Uses for the Neosho and Spring Rivers in Northeastern Oklahoma

USGS Publications Warehouse

Masoner, Jason R.; March, Ferrella

2006-01-01

Geographic Information Systems have many uses, one of which includes the reproducible computation of environmental characteristics that can be used to categorize hydrologic features. The Oklahoma Department of Wildlife Conservation and the Oklahoma Department of Environmental Quality are investigating Geographic Information Systems techniques to determine partial drainage-basin areas, stream-buffer areas, stream length, and land uses (drainage basin and stream characteristics) in northeastern Oklahoma. The U.S Geological Survey, in cooperation with Oklahoma Department of Wildlife Conservation and the Oklahoma Department of Environmental Quality, documented the methods used to determine drainage-basin and stream characteristics for the Neosho and Spring Rivers above Grand Lake Of the Cherokees in northeastern Oklahoma and calculated the characteristics. The drainage basin and stream characteristics can be used by the Oklahoma Department of Wildlife Conservation and the Oklahoma Department of Environmental Quality to aid in natural-resource assessments.

Non-iterative distance constraints enforcement for cloth drapes simulation

NASA Astrophysics Data System (ADS)

Hidajat, R. L. L. G.; Wibowo, Arifin, Z.; Suyitno

2016-03-01

A cloth simulation represents the behavior of cloth objects such as flag, tablecloth, or even garments has application in clothing animation for games and virtual shops. Elastically deformable models have widely used to provide realistic and efficient simulation, however problem of overstretching is encountered. We introduce a new cloth simulation algorithm that replaces iterative distance constraint enforcement steps with non-iterative ones for preventing over stretching in a spring-mass system for cloth modeling. Our method is based on a simple position correction procedure applied at one end of a spring. In our experiments, we developed a rectangle cloth model which is initially at a horizontal position with one point is fixed, and it is allowed to drape by its own weight. Our simulation is able to achieve a plausible cloth drapes as in reality. This paper aims to demonstrate the reliability of our approach to overcome overstretches while decreasing the computational cost of the constraint enforcement process due to an iterative procedure that is eliminated.

Periodic spring-mass running over uneven terrain through feedforward control of landing conditions.

PubMed

Palmer, Luther R; Eaton, Caitrin E

2014-09-01

This work pursues a feedforward control algorithm for high-speed legged locomotion over uneven terrain. Being able to rapidly negotiate uneven terrain without visual or a priori information about the terrain will allow legged systems to be used in time-critical applications and alongside fast-moving humans or vehicles. The algorithm is shown here implemented on a spring-loaded inverted pendulum model in simulation, and can be configured to approach fixed running height over uneven terrain or self-stable terrain following. Offline search identifies unique landing conditions that achieve a desired apex height with a constant stride period over varying ground levels. Because the time between the apex and touchdown events is directly related to ground height, the landing conditions can be computed in real time as continuous functions of this falling time. Enforcing a constant stride period reduces the need for inertial sensing of the apex event, which is nontrivial for physical systems, and allows for clocked feedfoward control of the swing leg.

Space Shuttle Main Engine structural analysis and data reduction/evaluation. Volume 2: High pressure oxidizer turbo-pump turbine end bearing analysis

NASA Technical Reports Server (NTRS)

Sisk, Gregory A.

1989-01-01

The high-pressure oxidizer turbopump (HPOTP) consists of two centrifugal pumps, on a common shaft, that are directly driven by a hot-gas turbine. Pump shaft axial thrust is balanced in that the double-entry main inducer/impeller is inherently balanced and the thrusts of the preburner pump and turbine are nearly equal but opposite. Residual shaft thrust is controlled by a self-compensating, non-rubbing, balance piston. Shaft hang-up must be avoided if the balance piston is to perform properly. One potential cause of shaft hang-up is contact between the Phase 2 bearing support and axial spring cartridge of the HPOTP main pump housing. The status of the bearing support/axial spring cartridge interface is investigated under current loading conditions. An ANSYS version 4.3, three-dimensional, finite element model was generated on Lockheed's VAX 11/785 computer. A nonlinear thermal analysis was then executed on the Marshall Space Flight Center Engineering Analysis Data System (EADS). These thermal results were then applied along with the interference fit and bolt preloads to the model as load conditions for a static analysis to determine the gap status of the bearing support/axial spring cartridge interface. For possible further analysis of the local regions of HPOTP main pump housing assembly, detailed ANSYS submodels were generated using I-DEAS Geomod and Supertab (Appendix A).

Dynamic behavior and deformation analysis of the fish cage system using mass-spring model

NASA Astrophysics Data System (ADS)

Lee, Chun Woo; Lee, Jihoon; Park, Subong

2015-06-01

Fish cage systems are influenced by various oceanic conditions, and the movements and deformation of the system by the external forces can affect the safety of the system itself, as well as the species of fish being cultivated. Structural durability of the system against environmental factors has been major concern for the marine aquaculture system. In this research, a mathematical model and a simulation method were presented for analyzing the performance of the large-scale fish cage system influenced by current and waves. The cage system consisted of netting, mooring ropes, floats, sinkers and floating collar. All the elements were modeled by use of the mass-spring model. The structures were divided into finite elements and mass points were placed at the mid-point of each element, and mass points were connected by springs without mass. Each mass point was applied to external and internal forces, and total force was calculated in every integration step. The computation method was applied to the dynamic simulation of the actual fish cage systems rigged with synthetic fiber and copper wire simultaneously influenced by current and waves. Here, we also tried to find a relevant ratio between buoyancy and sinking force of the fish cages. The simulation results provide improved understanding of the behavior of the structure and valuable information concerning optimum ratio of the buoyancy to sinking force according to current speeds.

Effect of cyclical forces on the periodontal ligament and alveolar bone remodeling during orthodontic tooth movement

PubMed Central

Kalajzic, Zana; Peluso, Elizabeth Blake; Utreja, Achint; Dyment, Nathaniel; Nihara, Jun; Xu, Manshan; Chen, Jing; Uribe, Flavio; Wadhwa, Sunil

2014-01-01

Objective To investigate the effect of externally applied cyclical (vibratory) forces on the rate of tooth movement, the structural integrity of the periodontal ligament, and alveolar bone remodeling. Methods Twenty-six female Sprague-Dawley rats (7 weeks old) were divided into four groups: CTRL (unloaded), VBO (molars receiving a vibratory stimulus only), TMO (molars receiving an orthodontic spring only), and TMO+VB (molars receiving an orthodontic spring and the additional vibratory stimulus). In TMO and TMO+VB groups, the rat first molars were moved mesially for 2 weeks using Nickel-Titanium coil spring delivering 25 g of force. In VBO and TMO+VB groups, cyclical forces at 0.4 N and 30 Hz were applied occlusally twice a week for 10 minutes. Microfocus X-ray computed tomography analysis and tooth movement measurements were performed on the dissected rat maxillae. Tartrate-resistant acid phosphatase staining and collagen fiber assessment were performed on histological sections. Results Cyclical forces significantly inhibited the amount of tooth movement. Histological analysis showed marked disorganization of the collagen fibril structure of the periodontal ligament during tooth movement. Tooth movement caused a significant increase in osteoclast parameters on the compression side of alveolar bone and a significant decrease in bone volume fraction in the molar region compared to controls. Conclusions Tooth movement was significantly inhibited by application of cyclical forces. PMID:23937517

Essential oil from Ocimum basilicum (Omani Basil): a desert crop.

PubMed

Al-Maskri, Ahmed Yahya; Hanif, Muhammad Asif; Al-Maskari, Masoud Yahya; Abraham, Alfie Susan; Al-sabahi, Jamal Nasser; Al-Mantheri, Omar

2011-10-01

The focus of the present study was on the influence of season on yield, chemical composition, antioxidant and antifungal activities of Omani basil (Ocimum basilicum) oil. The present study involved only one of the eight Omani basil varieties. The hydro-distilled essential oil yields were computed to be 0.1%, 0.3% and 0.1% in the winter, spring and summer seasons, respectively. The major components identified were L- linalool (26.5-56.3%), geraniol (12.1-16.5%), 1,8-cineole (2.5-15.1%), p-allylanisole (0.2-13.8%) and DL-limonene (0.2-10.4%). A noteworthy extra component was beta- farnesene, which was exclusively detected in the oil extracted during winter and spring at 6.3% and 5.8%, respectively. The essential oil composition over the different seasons was quite idiosyncratic, in which the principal components of one season were either trivial or totally absent in another. The essential oil extracted in spring exhibited the highest antioxidant activity (except DPPH scavenging ability) in comparison with the oils from other seasons. The basil oil was tested against pathogenic fungi viz. Aspergillus niger, A. fumigatus, Penicillium italicum and Rhizopus stolonifer using a disc diffusion method, and by determination of minimum inhibitory concentration. Surprisingly high antifungal values were found highlighting the potential of Omani basil as a preservative in the food and medical industries.

Relative Weight of Brown Trout and Lake Trout in Blue Mesa Reservoir, Colorado

DTIC Science & Technology

2012-01-27

Published data concerning the standard weight in lake trout (Salvelinus namaycush) and brown trout (salmo trutta) have been established. The...standard weights can be used to compute relative weights for data collected in the spring and summer of 2011 for brown trout and lake trout in the Blue Mesa...Reservoir, Colorado. The mean relative weight of a sample of 100 brown trout ranging in length from 260 to 432 mm was 80.01 +/- 0.74, showing that the

Computer Programs for Sun and Moon Illuminance with Contingent Tables and Diagrams

DTIC Science & Technology

1987-02-19

36 1930 215 /// /// 35 2012 154 /// /// 34 2109 125 /// /// 17 39 1903 229 /// III 38 1936 212 /// /// 37 2017 151 /// /// 36 2113 123 /// /// 35... Texarkana 122 38 Nape 105 39 Colorado Springs 91 36 TftfaWB 115 35 Needle« 107 41 Columbine 91 36 Tuekerman 122 38 Oakland 109 37 Cortez 94 35 Van...Christiansburg 96 33 Tarrall 112 40 Provo 77 37 Claramont 94 33 Texarkana 111 42 Randolph 80 38 Clifton Forge 99 33 Threekmorton 112 39 Richfield 82

Architecture, Design, and System; Performance Assessment and Development Methodology for Computer-Based Systems. Volume 1. Methodology Description, Discussion, and Assessment,

DTIC Science & Technology

1983-12-30

AD-Ri46 57? ARCHITECTURE DESIGN AND SYSTEM; PERFORMANCE ASSESSMENT i/i AND DEVELOPMENT ME..(U) NAVAL SURFACE WEAPONS CENTER SILYER SPRING MD J...AD-A 146 577 NSIWC TR 83-324 ARCHITECTURE , DESIGN , AND SYSTEM; PERFORMANCE ASSESSMENT AND DEVELOPMENT METHODOLOGY...REPORT NUMBER 12. GOVT ACCESSION NO.3. RECIPIENT’S CATALOG NUMBER NSWC TR 83-324 10- 1 1 51’ 4. ?ITLE (and subtitle) ARCHITECTURE , DESIGN , AND SYSTEM; S

Applying spatial analysis techniques to assess the suitability of multipurpose uses of spring water in the Jiaosi Hot Spring Region, Taiwan

NASA Astrophysics Data System (ADS)

Jang, Cheng-Shin

2016-04-01

The Jiaosi Hot Spring Region is located in northeastern Taiwan and is rich in geothermal springs. The geothermal development of the Jiaosi Hot Spring Region dates back to the 18th century and currently, the spring water is processed for various uses, including irrigation, aquaculture, swimming, bathing, foot spas, and recreational tourism. Because of the proximity of the Jiaosi Hot Spring Region to the metropolitan area of Taipei City, the hot spring resources in this region attract millions of tourists annually. Recently, the Taiwan government is paying more attention to surveying the spring water temperatures in the Jiaosi Hot Spring Region because of the severe spring water overexploitation, causing a significant decline in spring water temperatures. Furthermore, the temperature of spring water is a reliable indicator for exploring the occurrence and evolution of springs and strongly affects hydrochemical reactions, components, and magnitudes. The multipurpose uses of spring water can be dictated by the temperature of the water. Therefore, accurately estimating the temperature distribution of the spring water is critical in the Jiaosi Hot Spring Region to facilitate the sustainable development and management of the multipurpose uses of the hot spring resources. To evaluate the suitability of spring water for these various uses, this study spatially characterized the spring water temperatures of the Jiaosi Hot Spring Region by using ordinary kriging (OK), sequential Gaussian simulation (SGS), and geographical information system (GIS). First, variogram analyses were used to determine the spatial variability of spring water temperatures. Next, OK and SGS were adopted to model the spatial distributions and uncertainty of the spring water temperatures. Finally, the land use (i.e., agriculture, dwelling, public land, and recreation) was determined and combined with the estimated distributions of the spring water temperatures using GIS. A suitable development strategy for the multipurpose uses of spring water is proposed according to the integration of the land use and spring water temperatures. The study results indicate that OK, SGS, and GIS are capable of characterizing spring water temperatures and the suitability of multipurpose uses of spring water. SGS realizations are more robust than OK estimates for characterizing spring water temperatures. Furthermore, current land use is almost ideal in the Jiaosi Hot Spring Region according to the estimated spatial pattern of spring water temperatures. Keywords: Hot spring; Temperature; Land use; Ordinary kriging; Sequential Gaussian simulation; Geographical information system

Characterization of the hydrology, water chemistry, and aquatic communities of selected springs in the St. Johns River Water Management District, Florida, 2004

USGS Publications Warehouse

Phelps, G.G.; Walsh, Stephen J.; Gerwig, Robert M.; Tate, William B.

2006-01-01

The hydrology, water chemistry, and aquatic communities of Silver Springs, De Leon Spring, Gemini Springs, and Green Spring in the St. Johns River Water Management District, Florida, were studied in 2004 to provide a better understanding of each spring and to compile data of potential use in future water-management decisions. Ground water that discharges from these and other north-central Florida springs originates from the Upper Floridan aquifer of the Floridan aquifer system, a karstic limestone aquifer that extends throughout most of the State's peninsula. This report summarizes data about flow, water chemistry, and aquatic communities, including benthic invertebrates, fishes, algae, and aquatic macrophytes collected by the U.S. Geological Survey, the St. Johns River Water Management District, and the Florida Department of Environmental Protection during 2004, as well as some previously collected data. Differences in water chemistry among these springs reflect local differences in water chemistry in the Upper Floridan aquifer. The three major springs sampled at the Silver Springs group (the Main Spring, Blue Grotto, and the Abyss) have similar proportions of cations and anions but vary in nitrate and dissolved oxygen concentrations. Water from Gemini Springs and Green Spring has higher proportions of sodium and chloride than the Silver Springs group. Water from De Leon Spring also has higher proportions of sodium and chloride than the Silver Springs group but lower proportions of calcium and bicarbonate. Nitrate concentrations have increased over the period of record at all of the springs except Green Spring. Compounds commonly found in wastewater were found in all the springs sampled. The most commonly detected compound was the insect repellant N,N'-diethyl-methyl-toluamide (DEET), which was found in all the springs sampled except De Leon Spring. The pesticide atrazine and its degradate 2-chloro-4-isopropylamino-6-amino-s-triazine (CIAT) were detected in water from the Silver Springs group and in both boils at Gemini Springs. No pesticides were detected in water samples from De Leon Spring and Green Spring. Evidence of denitrification was indicated by the presence of excess nitrogen gas in water samples from most of the springs. Aquatic communities varied among the springs. Large floating mats of cyanobacteria (blue-green algae), identified as Lyngbya wollei, were observed in De Leon Spring during all sampling events in 2004. At Gemini Springs, the dominant periphyton was Rhizoclonium sp. Of the three springs sampled for benthic invertebrates, De Leon Spring had the highest overall species richness and most disturbance intolerant species (Florida Index = 4). Green Spring had the lowest species richness of the springs sampled. Based on qualitative comparisons, overall macroinvertebrate species richness seemed to be negatively related to magnesium, potassium, sodium, and specific conductance. Invertebrate abundance was greatest when dissolved oxygen and nitrate were high but phosphorus and potassium concentrations were low. Dipteran abundance seemed to be positively associated with specific conductance and total organic carbon but negatively associated with nitrate-N. Amphipods were the numerically dominant group collected in most (six of nine) collections. Shifts in amphipod abundance of the two species collected (Gammarus sp. and Hyalella azteca) varied by season among the three springs, but there were no trends evident in the variation. Fish populations were relatively species-rich at the Silver Springs group, De Leon Spring, and Gemini Springs, but not at Green Spring. Nonindigenous fish species were observed at all springs except Green Spring.

Assessment of vulnerability in karst aquifers using a quantitative integrated numerical model: catchment characterization and high resolution monitoring - Application to semi-arid regions- Lebanon.

NASA Astrophysics Data System (ADS)

Doummar, Joanna; Aoun, Michel; Andari, Fouad

2016-04-01

Karst aquifers are highly heterogeneous and characterized by a duality of recharge (concentrated; fast versus diffuse; slow) and a duality of flow which directly influences groundwater flow and spring responses. Given this heterogeneity in flow and infiltration, karst aquifers do not always obey standard hydraulic laws. Therefore the assessment of their vulnerability reveals to be challenging. Studies have shown that vulnerability of aquifers is highly governed by recharge to groundwater. On the other hand specific parameters appear to play a major role in the spatial and temporal distribution of infiltration on a karst system, thus greatly influencing the discharge rates observed at a karst spring, and consequently the vulnerability of a spring. This heterogeneity can only be depicted using an integrated numerical model to quantify recharge spatially and assess the spatial and temporal vulnerability of a catchment for contamination. In the framework of a three-year PEER NSF/USAID funded project, the vulnerability of a karst catchment in Lebanon is assessed quantitatively using a numerical approach. The aim of the project is also to refine actual evapotranspiration rates and spatial recharge distribution in a semi arid environment. For this purpose, a monitoring network was installed since July 2014 on two different pilot karst catchment (drained by Qachqouch Spring and Assal Spring) to collect high resolution data to be used in an integrated catchment numerical model with MIKE SHE, DHI including climate, unsaturated zone, and saturated zone. Catchment characterization essential for the model included geological mapping and karst features (e.g., dolines) survey as they contribute to fast flow. Tracer experiments were performed under different flow conditions (snow melt and low flow) to delineate the catchment area, reveal groundwater velocities and response to snowmelt events. An assessment of spring response after precipitation events allowed the estimation of the fast infiltration component. A series of laboratory tests were performed to acquire physical values to be used as a benchmark for model parameterization, such as laboratory tests on soils for conductivity at saturation and grain size analysis. Time series used for input or calibration were collected and computed from continuous high resolution monitoring of climatic data, moisture variation in the soil, and discharge at the investigated spring. This similar model approach used on a catchment site in Germany is to be applied and validated on two pilot karst catchments in Lebanon governed by semi-arid climatic conditions. References Doummar J., Sauter M., Geyer T., 2012. Simulation of flow processes in a large scale karst system with an integrated catchment model (Mike She) - Identification of relevant parameters influencing spring discharge. Journal of Hydrology, v. 426-427- p 112-123. Jukić, D., and Denić-Jukić, V., 2009. Groundwater balance estimation in karst by using a conceptual rainfall-runoff model. Journal of Hydrology, v. 373- p 302-315

Evaluation of acoustic doppler velocity meters to quantify flow from Comal Springs and San Marcos Springs, Texas

USGS Publications Warehouse

Gary, Marcus O.; Gary, Robin H.; Asquith, William H.

2008-01-01

Comal Springs and San Marcos Springs are the two largest springs in Texas, are major discharge points for the San Antonio segment of the Edwards aquifer, and provide habitat for several Federally listed endangered species that depend on adequate springflows for survival. It is therefore imperative that the Edwards Aquifer Authority have accurate and timely springflow data to guide resource management. Discharge points for Comal Springs and San Marcos Springs are submerged in Landa Lake and in Spring Lake, respectively. Flows from the springs currently (2008) are estimated by the U.S Geological Survey in real time as surface-water discharge from conventional stage-discharge ratings at sites downstream from each spring. Recent technological advances and availability of acoustic Doppler velocity meters (ADVMs) now provide tools to collect data (stream velocity) related to springflow that could increase accuracy of real-time estimates of the springflows. The U.S. Geological Survey, in cooperation with the Edwards Aquifer Authority, did a study during May 2006 through September 2007 to evaluate ADVMs to quantify flow from Comal and San Marcos Springs. The evaluation was based on two monitoring approaches: (1) placement of ADVMs in important spring orifices - spring run 3 and spring 7 at Comal Springs, and diversion spring at San Marcos Springs; and (2) placement of ADVMs at the nearest flowing streams - Comal River new and old channels for Comal Springs, Spring Lake west and east outflow channels and current (2008) San Marcos River streamflow-gaging site for San Marcos Springs. For Comal Springs, ADVM application at spring run 3 and spring 7 was intended to indicate whether the flows of spring run 3 and spring 7 can be related to total springflow. The findings indicate that velocity data from both discharge features, while reflecting changes in flow, do not reliably show a direct relation to measured streamflow and thus to total Comal Springs flow. ADVMs at the Comal River new channel and old channel sites provide data that potentially could yield more accurate real-time estimates of total Comal Springs flow than streamflow measured at the downstream Comal River site. For San Marcos Springs, the findings indicate shortcomings with ADVM installations at diversion spring and in the west and east outflow channels. However, the accuracy of streamflow measured at the San Marcos River gage as an estimate of real-time San Marcos Springs flow could potentially be increased through use of ADVM data from that site.

Spring performance tester for miniature extension springs

DOEpatents

Salzbrenner, Bradley; Boyce, Brad

2017-05-16

A spring performance tester and method of testing a spring are disclosed that has improved accuracy and precision over prior art spring testers. The tester can perform static and cyclic testing. The spring tester can provide validation for product acceptance as well as test for cyclic degradation of springs, such as the change in the spring rate and fatigue failure.

Variable stiffness torsion springs

NASA Astrophysics Data System (ADS)

Alhorn, Dean C.; Polites, Michael E.

1994-05-01

In a torsion spring the spring action is a result of the relationships between the torque applied in twisting the spring, the angle through which the torsion spring twists, and the modulus of elasticity of the spring material in shear. Torsion springs employed industrially have been strips, rods, or bars, generally termed shafts, capabable of being flexed by twisting their axes. They rely on the variations in shearing forces to furnish an internal restoring torque. In the torsion springs herein the restoring torque is external and therefore independent of the shearing modulus of elasticity of the torsion spring shaft. Also provided herein is a variable stiffness torsion spring. This torsion spring can be so adjusted as to have a given spring constant. Such variable stiffness torsion springs are extremely useful in gimballed payloads such as sensors, telescopes, and electronic devices on such platforms as a space shuttle or a space station.

Variable stiffness torsion springs

NASA Technical Reports Server (NTRS)

Alhorn, Dean C. (Inventor); Polites, Michael E. (Inventor)

1995-01-01

In a torsion spring the spring action is a result of the relationships between the torque applied in twisting the spring, the angle through which the torsion spring twists, and the modulus of elasticity of the spring material in shear. Torsion springs employed industrially have been strips, rods, or bars, generally termed shafts, capabable of being flexed by twisting their axes. They rely on the variations in shearing forces to furnish an internal restoring torque. In the torsion springs herein the restoring torque is external and therefore independent of the shearing modulus of elasticity of the torsion spring shaft. Also provided herein is a variable stiffness torsion spring. This torsion spring can be so adjusted as to have a given spring constant. Such variable stiffness torsion springs are extremely useful in gimballed payloads such as sensors, telescopes, and electronic devices on such platforms as a space shuttle or a space station.

Variable stiffness torsion springs

NASA Astrophysics Data System (ADS)

Alhorn, Dean C.; Polites, Michael E.

1995-08-01

In a torsion spring the spring action is a result of the relationships between the torque applied in twisting the spring, the angle through which the torsion spring twists, and the modulus of elasticity of the spring material in shear. Torsion springs employed industrially have been strips, rods, or bars, generally termed shafts, capabable of being flexed by twisting their axes. They rely on the variations in shearing forces to furnish an internal restoring torque. In the torsion springs herein the restoring torque is external and therefore independent of the shearing modulus of elasticity of the torsion spring shaft. Also provided herein is a variable stiffness torsion spring. This torsion spring can be so adjusted as to have a given spring constant. Such variable stiffness torsion springs are extremely useful in gimballed payloads such as sensors, telescopes, and electronic devices on such platforms as a space shuttle or a space station.

Variable stiffness torsion springs

NASA Technical Reports Server (NTRS)

Alhorn, Dean C. (Inventor); Polites, Michael E. (Inventor)

1994-01-01

In a torsion spring the spring action is a result of the relationships between the torque applied in twisting the spring, the angle through which the torsion spring twists, and the modulus of elasticity of the spring material in shear. Torsion springs employed industrially have been strips, rods, or bars, generally termed shafts, capabable of being flexed by twisting their axes. They rely on the variations in shearing forces to furnish an internal restoring torque. In the torsion springs herein the restoring torque is external and therefore independent of the shearing modulus of elasticity of the torsion spring shaft. Also provided herein is a variable stiffness torsion spring. This torsion spring can be so adjusted as to have a given spring constant. Such variable stiffness torsion springs are extremely useful in gimballed payloads such as sensors, telescopes, and electronic devices on such platforms as a space shuttle or a space station.

Geohydrologic Investigations and Landscape Characteristics of Areas Contributing Water to Springs, the Current River, and Jacks Fork, Ozark National Scenic Riverways, Missouri

USGS Publications Warehouse

Mugel, Douglas N.; Richards, Joseph M.; Schumacher, John G.

2009-01-01

The Ozark National Scenic Riverways (ONSR) is a narrow corridor that stretches for approximately 134 miles along the Current River and Jacks Fork in southern Missouri. Most of the water flowing in the Current River and Jacks Fork is discharged to the rivers from springs within the ONSR, and most of the recharge area of these springs is outside the ONSR. This report describes geohydrologic investigations and landscape characteristics of areas contributing water to springs and the Current River and Jacks Fork in the ONSR. The potentiometric-surface map of the study area for 2000-07 shows that the groundwater divide extends beyond the surface-water divide in some places, notably along Logan Creek and the northeastern part of the study area, indicating interbasin transfer of groundwater between surface-water basins. A low hydraulic gradient occurs in much of the upland area west of the Current River associated with areas of high sinkhole density, which indicates the presence of a network of subsurface karst conduits. The results of a low base-flow seepage run indicate that most of the discharge in the Current River and Jacks Fork was from identified springs, and a smaller amount was from tributaries whose discharge probably originated as spring discharge, or from springs or diffuse groundwater discharge in the streambed. Results of a temperature profile conducted on an 85-mile reach of the Current River indicate that the lowest average temperatures were within or downstream from inflows of springs. A mass-balance on heat calculation of the discharge of Bass Rock Spring, a previously undescribed spring, resulted in an estimated discharge of 34.1 cubic feet per second (ft3/s), making it the sixth largest spring in the Current River Basin. The 13 springs in the study area for which recharge areas have been estimated accounted for 82 percent (867 ft3/s of 1,060 ft3/s) of the discharge of the Current River at Big Spring during the 2006 seepage run. Including discharge from other springs, the cumulative discharge from springs was over 90 percent of the river discharge at most of the spring locations, and was 92 percent at Big Spring and at the lower end of the ONSR. The discharge from the 1.9-mile long Pulltite Springs Complex measured in the 2006 seepage run was 88 ft3/s. Most of this (77 ft3/s) was from the first approximately 0.25 mi of the Pulltite Springs Complex. It has been estimated that the annual mean discharge from the Current River Springs Complex is 125 ft3/s, based on an apparent discharge of 50 ft3/s during a 1966 U.S. Geological Survey seepage run. However, a reinterpretation of the 1966 seepage run data shows that the discharge from the Current River Springs Complex instead was about 12.6 ft3/s, and the annual mean discharge was estimated to be 32 ft3/s, substantially less than 125 ft3/s. The 2006 seepage run showed a gain of only 12 ft3/s from the combined Round Spring and Current River Springs Complex from the mouth of Sinking Creek to 0.7 mi upstream from Root Hollow. The 2006 temperature profile measurements did not indicate any influx of spring discharge throughout the length of the Current River Springs Complex. The spring recharge areas with the largest number of identified sinkholes are Big Spring, Alley Spring, and Welch Spring. The spring recharge areas with the largest number of sinkholes per square mile of recharge area are Alley Spring, Blue Spring (Jacks Fork), Welch Spring, and Round Spring and the Current River Springs Complex. Using the currently known locations of losing streams, the Big Spring recharge area has the largest number of miles of losing stream, and the Bass Rock Spring recharge area has the largest number of miles of losing stream per unit recharge area. The spring recharge areas with the most open land and the least forested land per unit recharge area are Blue Spring (Jacks Fork), Welch Spring, Montauk Springs, and Alley Spring. The spring recharge areas with the least amount

Constraint methods that accelerate free-energy simulations of biomolecules.

PubMed

Perez, Alberto; MacCallum, Justin L; Coutsias, Evangelos A; Dill, Ken A

2015-12-28

Atomistic molecular dynamics simulations of biomolecules are critical for generating narratives about biological mechanisms. The power of atomistic simulations is that these are physics-based methods that satisfy Boltzmann's law, so they can be used to compute populations, dynamics, and mechanisms. But physical simulations are computationally intensive and do not scale well to the sizes of many important biomolecules. One way to speed up physical simulations is by coarse-graining the potential function. Another way is to harness structural knowledge, often by imposing spring-like restraints. But harnessing external knowledge in physical simulations is problematic because knowledge, data, or hunches have errors, noise, and combinatoric uncertainties. Here, we review recent principled methods for imposing restraints to speed up physics-based molecular simulations that promise to scale to larger biomolecules and motions.

Blade loss transient dynamics analysis, volume 2. Task 2: TETRA 2 user's manual

NASA Technical Reports Server (NTRS)

Black, Gerald; Gallardo, Vincente C.

1986-01-01

This is the user's manual for the TETRA 2 Computer Code, a program developed in the NASA-Lewis Blade Loss Program. TETRA 2 calculates a turbine engine's dynamic structural response from applied stimuli. The calculation options are: (1) transient response; and (2) steady state forced response. Based on the method of modal syntheses, the program allows the use of linear, as well as nonlinear connecting elements. Both transient and steady state options can include: flexible Bladed Disk Module, and Nonlinear Connecting Elements (including deadband, hardening/softening spring). The transient option has the additional capability to calculate response with a squeeze film bearing module. TETRA 2 output is summarized in a plotfile which permits post processing such as FFT or graphical animation with the proper software and computer equipment.

Virtual-pulse time integral methodology: A new explicit approach for computational dynamics - Theoretical developments for general nonlinear structural dynamics

NASA Technical Reports Server (NTRS)

Chen, Xiaoqin; Tamma, Kumar K.; Sha, Desong

1993-01-01

The present paper describes a new explicit virtual-pulse time integral methodology for nonlinear structural dynamics problems. The purpose of the paper is to provide the theoretical basis of the methodology and to demonstrate applicability of the proposed formulations to nonlinear dynamic structures. Different from the existing numerical methods such as direct time integrations or mode superposition techniques, the proposed methodology offers new perspectives and methodology of development, and possesses several unique and attractive computational characteristics. The methodology is tested and compared with the implicit Newmark method (trapezoidal rule) through a nonlinear softening and hardening spring dynamic models. The numerical results indicate that the proposed explicit virtual-pulse time integral methodology is an excellent alternative for solving general nonlinear dynamic problems.

Spaceflight mechanics 1992; Proceedings of the 2nd AAS/AIAA Meeting, Colorado Springs, CO, Feb. 24-26, 1992. Pts. 1 & 2

NASA Astrophysics Data System (ADS)

Diehl, Roger E.; Schinnerer, Ralph G.; Williamson, Walton E.; Boden, Daryl G.

The present conference discusses topics in orbit determination, tethered satellite systems, celestial mechanics, guidance optimization, flexible body dynamics and control, attitude dynamics and control, Mars mission analyses, earth-orbiting mission analysis/debris, space probe mission analyses, and orbital computation numerical analyses. Attention is given to electrodynamic forces for control of tethered satellite systems, orbiting debris threats to asteroid flyby missions, launch velocity requirements for interceptors of short range ballistic missiles, transfers between libration-point orbits in the elliptic restricted problem, minimum fuel spacecraft reorientation, orbital guidance for hitting a fixed point at maximum speed, efficient computation of satellite visibility periods, orbit decay and reentry prediction for space debris, and the determination of satellite close approaches.

Inter-annual and spatial variability of Hamon potential evapotranspiration model coefficients

USGS Publications Warehouse

McCabe, Gregory J.; Hay, Lauren E.; Bock, Andy; Markstrom, Steven L.; Atkinson, R. Dwight

2015-01-01

Monthly calibrated values of the Hamon PET coefficient (C) are determined for 109,951 hydrologic response units (HRUs) across the conterminous United States (U.S.). The calibrated coefficient values are determined by matching calculated mean monthly Hamon PET to mean monthly free-water surface evaporation. For most locations and months the calibrated coefficients are larger than the standard value reported by Hamon. The largest changes in the coefficients were for the late winter/early spring and fall months, whereas the smallest changes were for the summer months. Comparisons of PET computed using the standard value of C and computed using calibrated values of C indicate that for most of the conterminous U.S. PET is underestimated using the standard Hamon PET coefficient, except for the southeastern U.S.

Special Education Students Improve Academic Performance through Problem-Based Learning and Technology

NASA Astrophysics Data System (ADS)

Freeman, S.; Kintsch, A.

2003-12-01

Boulder High School Special Education students work in teams on donated wireless computers to solve problems created by global climate change. Their text is Richard Somerville's The Forgiving Air. They utilize Wheeling Jesuit University's remote sensing web site and private computer bulletin board. Their central source for problem-based learning (PBL) is www.cotf.edu, NASA's Classroom of the Future Global Change web site. As a result, students not only improve their abilities to write, read, do math and research, speak, and work as team members, they also improve self-esteem, resilience, and willingness to take more challenging classes. Two special education students passed AP exams, Calculus and U.S. Government, last spring and Jay Matthews of Newsweek rates Boulder High as 201st of the nation's top 1000 high schools.

Spaceflight mechanics 1992; Proceedings of the 2nd AAS/AIAA Meeting, Colorado Springs, CO, Feb. 24-26, 1992. Pts. 1 & 2

NASA Technical Reports Server (NTRS)

Diehl, Roger E. (Editor); Schinnerer, Ralph G. (Editor); Williamson, Walton E. (Editor); Boden, Daryl G. (Editor)

1992-01-01

The present conference discusses topics in orbit determination, tethered satellite systems, celestial mechanics, guidance optimization, flexible body dynamics and control, attitude dynamics and control, Mars mission analyses, earth-orbiting mission analysis/debris, space probe mission analyses, and orbital computation numerical analyses. Attention is given to electrodynamic forces for control of tethered satellite systems, orbiting debris threats to asteroid flyby missions, launch velocity requirements for interceptors of short range ballistic missiles, transfers between libration-point orbits in the elliptic restricted problem, minimum fuel spacecraft reorientation, orbital guidance for hitting a fixed point at maximum speed, efficient computation of satellite visibility periods, orbit decay and reentry prediction for space debris, and the determination of satellite close approaches.

77 FR 49601 - Endangered and Threatened Wildlife and Plants; Endangered Status for Six West Texas Aquatic...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-16

... very system (four restricted range. springs). Phantom Lake springsnail.... San Solomon Spring very rare in a very system (four restricted range. springs). diminutive amphipod......... San Solomon Spring... Solomon Spring system to include four different existing spring outflows: San Solomon Spring, Giffin...

Estimating diffusivity from the mixed layer heat and salt balances in the North Pacific

NASA Astrophysics Data System (ADS)

Cronin, M. F.; Pelland, N.; Emerson, S. R.; Crawford, W. R.

2015-12-01

Data from two National Oceanographic and Atmospheric Administration (NOAA) surface moorings in the North Pacific, in combination with data from satellite, Argo floats and glider (when available), are used to evaluate the residual diffusive flux of heat across the base of the mixed layer from the surface mixed layer heat budget. The diffusion coefficient (i.e., diffusivity) is then computed by dividing the diffusive flux by the temperature gradient in the 20-m transition layer just below the base of the mixed layer. At Station Papa in the NE Pacific subpolar gyre, this diffusivity is 1×10-4 m2/s during summer, increasing to ~3×10-4 m2/s during fall. During late winter and early spring, diffusivity has large errors. At other times, diffusivity computed from the mixed layer salt budget at Papa correlate with those from the heat budget, giving confidence that the results are robust for all seasons except late winter-early spring and can be used for other tracers. In comparison, at the Kuroshio Extension Observatory (KEO) in the NW Pacific subtropical recirculation gyre, somewhat larger diffusivity are found based upon the mixed layer heat budget: ~ 3×10-4 m2/s during the warm season and more than an order of magnitude larger during the winter, although again, wintertime errors are large. These larger values at KEO appear to be due to the increased turbulence associated with the summertime typhoons, and weaker wintertime stratification.

Estimating diffusivity from the mixed layer heat and salt balances in the North Pacific

NASA Astrophysics Data System (ADS)

Cronin, Meghan F.; Pelland, Noel A.; Emerson, Steven R.; Crawford, William R.

2015-11-01

Data from two National Oceanographic and Atmospheric Administration (NOAA) surface moorings in the North Pacific, in combination with data from satellite, Argo floats and glider (when available), are used to evaluate the residual diffusive flux of heat across the base of the mixed layer from the surface mixed layer heat budget. The diffusion coefficient (i.e., diffusivity) is then computed by dividing the diffusive flux by the temperature gradient in the 20 m transition layer just below the base of the mixed layer. At Station Papa in the NE Pacific subpolar gyre, this diffusivity is 1 × 10-4 m2/s during summer, increasing to ˜3 × 10-4 m2/s during fall. During late winter and early spring, diffusivity has large errors. At other times, diffusivity computed from the mixed layer salt budget at Papa correlate with those from the heat budget, giving confidence that the results are robust for all seasons except late winter-early spring and can be used for other tracers. In comparison, at the Kuroshio Extension Observatory (KEO) in the NW Pacific subtropical recirculation gyre, somewhat larger diffusivities are found based upon the mixed layer heat budget: ˜ 3 × 10-4 m2/s during the warm season and more than an order of magnitude larger during the winter, although again, wintertime errors are large. These larger values at KEO appear to be due to the increased turbulence associated with the summertime typhoons, and weaker wintertime stratification.

Neuroplasticity-Based Cognitive and Linguistic Skills Training Improves Reading and Writing Skills in College Students

PubMed Central

Rogowsky, Beth A.; Papamichalis, Pericles; Villa, Laura; Heim, Sabine; Tallal, Paula

2013-01-01

This study reports an evaluation of the effect of computer-based cognitive and linguistic training on college students’ reading and writing skills. The computer-based training included a series of increasingly challenging software programs that were designed to strengthen students’ foundational cognitive skills (memory, attention span, processing speed, and sequencing) in the context of listening and higher level reading tasks. Twenty-five college students (12 native English language; 13 English Second Language), who demonstrated poor writing skills, participated in the training group. The training group received daily training during the spring semester (11 weeks) with the Fast ForWord Literacy (FFW-L) and upper levels of the Fast ForWord Reading series (Levels 3–5). The comparison group (n = 28) selected from the general college population did not receive training. Both the training and comparison groups attended the same university. All students took the Gates MacGinitie Reading Test (GMRT) and the Oral and Written Language Scales (OWLS) Written Expression Scale at the beginning (Time 1) and end (Time 2) of the spring college semester. Results from this study showed that the training group made a statistically greater improvement from Time 1 to Time 2 in both their reading skills and their writing skills than the comparison group. The group who received training began with statistically lower writing skills before training, but exceeded the writing skills of the comparison group after training. PMID:23533100

[History of hot spring bath treatment in China].

PubMed

Hao, Wanpeng; Wang, Xiaojun; Xiang, Yinghong; Gu Li, A Man; Li, Ming; Zhang, Xin

2011-07-01

As early as the 7th century B.C. (Western Zhou Dynasty), there is a recording as 'spring which contains sulfur could treat disease' on the Wentang Stele written by WANG Bao. Wenquan Fu written by ZHANG Heng in the Easten Han Dynasty also mentioned hot spring bath treatment. The distribution of hot springs in China has been summarized by LI Daoyuan in the Northern Wei Dynasty in his Shuijingzhu which recorded hot springs in 41 places and interpreted the definition of hot spring. Bencao Shiyi (by CHEN Cangqi, Tang Dynasty) discussed the formation of and indications for hot springs. HU Zai in the Song Dynasty pointed out distinguishing hot springs according to water quality in his book Yuyin Conghua. TANG Shenwei in the Song Dynasty noted in Jingshi Zhenglei Beiji Bencao that hot spring bath treatment should be combined with diet. Shiwu Bencao (Ming Dynasty) classified hot springs into sulfur springs, arsenicum springs, cinnabar springs, aluminite springs, etc. and pointed out their individual indications. Geologists did not start the work on distribution and water quality analysis of hot springs until the first half of the 20th century. There are 972 hot springs in Wenquan Jiyao (written by geologist ZHANG Hongzhao and published in 1956). In July 1982, the First National Geothermal Conference was held and it reported that there were more than 2600 hot springs in China. Since the second half of the 20th century, hot spring sanatoriums and rehabilitation centers have been established, which promoted the development of hot spring bath treatment.

Applying spatial analysis techniques to assess the suitability of multipurpose uses of spring water in the Jiaosi Hot Spring Region, Taiwan.

PubMed

Jang, Cheng-Shin; Huang, Han-Chen

2017-07-01

The Jiaosi Hot Spring Region is one of the most famous tourism destinations in Taiwan. The spring water is processed for various uses, including irrigation, aquaculture, swimming, bathing, foot spas, and recreational tourism. Moreover, the multipurpose uses of spring water can be dictated by the temperature of the water. To evaluate the suitability of spring water for these various uses, this study spatially characterized the spring water temperatures of the Jiaosi Hot Spring Region by integrating ordinary kriging (OK), sequential Gaussian simulation (SGS), and Geographic information system (GIS). First, variogram analyses were used to determine the spatial variability of spring water temperatures. Next, OK and SGS were adopted to model the spatial uncertainty and distributions of the spring water temperatures. Finally, the land use (i.e., agriculture, dwelling, public land, and recreation) was determined using GIS and combined with the estimated distributions of the spring water temperatures. A suitable development strategy for the multipurpose uses of spring water is proposed according to the integration of the land use and spring water temperatures. The study results indicate that the integration of OK, SGS, and GIS is capable of characterizing spring water temperatures and the suitability of multipurpose uses of spring water. SGS realizations are more robust than OK estimates for characterizing spring water temperatures compared to observed data. Furthermore, current land use is almost ideal in the Jiaosi Hot Spring Region according to the estimated spatial pattern of spring water temperatures.

Structural Inventory of Great Basin Geothermal Systems and Definition of Favorable Structural Settings

DOE Data Explorer

Faulds, James E.

2013-12-31

Over the course of the entire project, field visits were made to 117 geothermal systems in the Great Basin region. Major field excursions, incorporating visits to large groups of systems, were conducted in western Nevada, central Nevada, northwestern Nevada, northeastern Nevada, east‐central Nevada, eastern California, southern Oregon, and western Utah. For example, field excursions to the following areas included visits of multiple geothermal systems: - Northwestern Nevada: Baltazor Hot Spring, Blue Mountain, Bog Hot Spring, Dyke Hot Springs, Howard Hot Spring, MacFarlane Hot Spring, McGee Mountain, and Pinto Hot Springs in northwest Nevada. - North‐central to northeastern Nevada: Beowawe, Crescent Valley (Hot Springs Point), Dann Ranch (Hand‐me‐Down Hot Springs), Golconda, and Pumpernickel Valley (Tipton Hot Springs) in north‐central to northeast Nevada. - Eastern Nevada: Ash Springs, Chimney Hot Spring, Duckwater, Hiko Hot Spring, Hot Creek Butte, Iverson Spring, Moon River Hot Spring, Moorman Spring, Railroad Valley, and Williams Hot Spring in eastern Nevada. - Southwestern Nevada‐eastern California: Walley’s Hot Spring, Antelope Valley, Fales Hot Springs, Buckeye Hot Springs, Travertine Hot Springs, Teels Marsh, Rhodes Marsh, Columbus Marsh, Alum‐Silver Peak, Fish Lake Valley, Gabbs Valley, Wild Rose, Rawhide‐ Wedell Hot Springs, Alkali Hot Springs, and Baileys/Hicks/Burrell Hot Springs. - Southern Oregon: Alvord Hot Spring, Antelope Hot Spring‐Hart Mountain, Borax Lake, Crump Geyser, and Mickey Hot Spring in southern Oregon. - Western Utah: Newcastle, Veyo Hot Spring, Dixie Hot Spring, Thermo, Roosevelt, Cove Fort, Red Hill Hot Spring, Joseph Hot Spring, Hatton Hot Spring, and Abraham‐Baker Hot Springs. Structural controls of 426 geothermal systems were analyzed with literature research, air photos, google‐Earth imagery, and/or field reviews (Figures 1 and 2). Of the systems analyzed, we were able to determine the structural settings of more than 240 sites. However, we found that many “systems” consisted of little more than a warm or hot well in the central part of a basin. Such “systems” were difficult to evaluate in terms of structural setting in areas lacking in geophysical data. Developed database for structural catalogue in a master spreadsheet. Data components include structural setting, primary fault orientation, presence or absence of Quaternary faulting, reservoir lithology, geothermometry, presence or absence of recent magmatism, and distinguishing blind systems from those that have surface expressions. Reviewed site locations for all 426 geothermal systems– Confirmed and/or relocated spring and geothermal sites based on imagery, maps, and other information for master database. Many systems were mislocated in the original database. In addition, some systems that included several separate springs spread over large areas were divided into two or more distinct systems. Further, all hot wells were assigned names based on their location to facilitate subsequent analyses. We catalogued systems into the following eight major groups, based on the dominant pattern of faulting (Figure 1): - Major normal fault segments (i.e., near displacement maxima). - Fault bends. - Fault terminations or tips. - Step‐overs or relay ramps in normal faults. - Fault intersections. - Accommodation zones (i.e., belts of intermeshing oppositely dipping normal faults), - Displacement transfer zones whereby strike‐slip faults terminate in arrays of normal faults. - Transtensional pull‐aparts. These settings form a hierarchal pattern with respect to fault complexity. - Major normal faults and fault bends are the simplest. - Fault terminations are typically more complex than mid‐segments, as faults commonly break up into multiple strands or horsetail near their ends. - A fault intersection is generally more complex, as it generally contains both multiple fault strands and can include discrete di...

Design for pressure regulating components

NASA Technical Reports Server (NTRS)

Wichmann, H.

1973-01-01

The design development for Pressure Regulating Components included a regulator component trade-off study with analog computer performance verification to arrive at a final optimized regulator configuration for the Space Storable Propulsion Module, under development for a Jupiter Orbiter mission. This application requires the pressure regulator to be capable of long-term fluorine exposure. In addition, individual but basically identical (for purposes of commonality) units are required for separate oxidizer and fuel pressurization. The need for dual units requires improvement in the regulation accuracy over present designs. An advanced regulator concept was prepared featuring redundant bellows, all metallic/ceramic construction, friction-free guidance of moving parts, gas damping, and the elimination of coil springs normally used for reference forces. The activities included testing of actual size seat/poppet components to determine actual discharge coefficients and flow forces. The resulting data was inserted into the computer model of the regulator. Computer simulation of the propulsion module performance over two mission profiles indicated satisfactory minimization of propellant residual requirements imposed by regulator performance uncertainties.

Comparison of lens- and fiber-coupled CCD detectors for X-ray computed tomography

PubMed Central

Uesugi, K.; Hoshino, M.; Yagi, N.

2011-01-01

X-ray imaging detectors with an identical phosphor and a CCD chip but employing lens- and fiber-coupling between them have been compared. These are designed for X-ray imaging experiments, especially computed tomography, at the medium-length beamline at the SPring-8 synchrotron radiation facility. It was found that the transmittance of light to the CCD is about four times higher in the fiber-coupled detector. The uniformity of response in the lens-coupled detector has a global shading of up to 40%, while pixel-to-pixel variation owing to a chicken-wire pattern was dominant in the fiber-coupled detector. Apart from the higher transmittance, the fiber-coupled detector has a few characteristics that require attention when it is used for computed tomography, which are browning of the fiber, discontinuity in the image, image distortion, and dark spots in the chicken-wire pattern. Thus, it is most suitable for high-speed tomography of samples that tend to deform, for example biological and soft materials. PMID:21335908

The Dependence of the Spring Constant in the Linear Range on Spring Parameters

ERIC Educational Resources Information Center

Khotimah, Siti Nurul; Viridi, Sparisoma; Widayani; Khairurrijal

2011-01-01

In basic physics laboratories, springs are normally used to determine both spring constants and the Earth's gravitational acceleration. Students generally do not notice that the spring constant is not a universal constant, but depends on the spring parameters. This paper shows and verifies that the spring constant in the linear range is inversely…

Major thermal springs of Utah

USGS Publications Warehouse

Mundorff, J.C.

1970-01-01

As part of a study of the springs of Utah, reconnaissance data were obtained on the thermal, chemical, and geologic characteristics of the major thermal springs or Utah. Only three of the springs have temperatures near the boiling point of water; the maximum recorded temperatures of these springs range from 185° to 189° F. All three springs are in or near areas of late Tertiary or Quaternary volcanism.Temperatures of the thermal springs studied ranged from 68° to 189° F. Nearly all thermal springs in Utah are in or near fault zones. Very few of these springs issue from volcanic rocks, but several springs are close to areas of late Tertiary or Quaternary volcanic rocks.

Ground-Water, Surface-Water, and Water-Chemistry Data, Black Mesa Area, Northeastern Arizona - 2006-07

USGS Publications Warehouse

Truini, Margot; Macy, J.P.

2008-01-01

The N aquifer is the major source of water in the 5,400 square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use and the needs of a growing population. Precipitation in the Black Mesa area is typically about 6 to 14 inches per year. The water-monitoring program in the Black Mesa area began in 1971 and is designed to provide information about the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected for the monitoring program in the Black Mesa area from January 2006 to September 2007. The monitoring program includes measurements of (1) ground-water withdrawals, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, and (5) ground-water chemistry. Periodic testing of ground-water withdrawal meters is completed every 4 to 5 years. The Navajo Tribal Utility Authority (NTUA) yearly totals for the ground-water metered withdrawal data were unavailable in 2006 due to an up-grade within the NTUA computer network. Because NTUA data is often combined with Bureau of Indian Affairs data for the total withdrawals in a well system, withdrawals will not be published in this year's annual report. From 2006 to 2007, annually measured water levels in the Black Mesa area declined in 3 of 11 wells measured in the unconfined areas of the N aquifer, and the median change was 0.0 feet. Measurements indicated that water levels declined in 8 of 17 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was 0.2 feet. From the prestress period (prior to 1965) to 2007, the median water-level change for 30 wells was -11.1 feet. Median water-level changes were 2.9 feet for 11 wells measured in the unconfined areas and -40.2 feet for 19 wells measured in the confined area. Spring flow was measured once in 2006 and once in 2007 at Moenkopi School Spring. Flow decreased by 18.9 percent at Moenkopi School Spring. During the period of record, flow fluctuated, and a decreasing trend was apparent. Continuous records of surface-water discharge in the Black Mesa area have been collected from streamflow gages at the following sites: Moenkopi Wash at Moenkopi (1976 to 2006), Dinnebito Wash near Sand Springs (1993 to 2006), Polacca Wash near Second Mesa (1994 to 2006), and Pasture Canyon Springs (August 2004 to December 2006). Median flows during November, December, January, and February of each water year were used as an index of the amount of ground-water discharge to the above named sites. For the period of record at each streamflow-gaging station, the median winter flows have generally remained even, showing neither a significant increase nor decrease in flows. There is not a long enough period of record for Pasture Canyon Spring for a trend to be apparent. In 2007, water samples were collected from 1 well and 1 spring in the Black Mesa area and were analyzed for selected chemical constituents. Concentrations of dissolved solids, chloride, and sulfate have varied at Peabody well 5 for the period of record, and there is an apparent increasing trend. Dissolved-solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 12 years of record.

1. LOOKING NORTH, SHOWING IODINE SPRING (FOREGROUND), SALT SULPHUR SPRING ...

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

1. LOOKING NORTH, SHOWING IODINE SPRING (FOREGROUND), SALT SULPHUR SPRING (LEFT BACKGROUND), AND TWIN COTTAGES (UPPER RIGHT) (4 x 5 negative; 5 x 7 print) - Salt Sulpher Springs, U.S. Route 219, Salt Sulphur Springs, Monroe County, WV

Role of stratification on internal waves over the continental shelf in the Bay of Bengal : A case study

NASA Astrophysics Data System (ADS)

Pradhan, H. K.; Rao, A. D.; Sharma, M. J.

2013-12-01

Internal waves (IWs) in a continuously stratified medium may propagate vertically as well as horizontally in the continental shelf. The surface layer of the Bay of Bengal exhibit intricate stratification owing to the differential distribution of freshwaters. In the current study, occurance of low-frequency IWs during two different occasions (i) late winter monsoon (February, 2007) (ii) post-monsoon (October, 2006) is studied. MITgcm is configured on a regional scale with variable curvilinear grid on the western shelf of Bay of Bengal to study the maximum energy associated with IWs during spring-tide. The local stratification and sharp varying topography along the coast makes it a potential region for generation/propagation of IWs. Modified ETOPO2 bathymetry and high resolution temperature and salinity data from WOA09 is used along with QuikSCAT daily winds. Real-time tides are introduced as forcing to the model by including additional terms in the momenteum equations. The simulations of the tidal elevations are validated with the tide gauge data. It is found that amplitudes of the IWs vary significantly from spring to neap tide. Spectral analysis of the temperature oscillations reveals the IWs of semi-diurnal frequency are dominant over the region followed by diurnal component. Observations of amplitude and phase of IWs are used for model validation collected during field work from 18-20 October 2006 and 21-23 February 2007 offshore of Visakhapatnam. The IW energy computed from both observations and simulations are reasonably in good agreement. It is also noticed that the energy intensity modulates during a complete tidal cycle bearing the maximum at spring tide and is nearly six times as compared to that of the neap tide period. It is interesting to further examine how the IW energy generates/propagates over the shelf/slope topography in the presence of variable straification. The maximum energy associated with low-frequency IWs is computed across the depth during spring tide off Visakhapatnam and Pardeep. The simulations indicate that the maximum IW energy is confined to the continental shelf edge inferring that IWs activity is at its peak over the region. A comparison of the computed energy is made along the bottom topography off Visakhapatnam and Paradeep during Feb 2007 and Oct 2006 respectively. The energy is further intruded about 7km and 9km off Visakhapatnam and Paradeep respectively towards the coast during Oct 2006 as aganist that of Feb 2007. This is attributed to the fact that the presence of staratified waters are closer to the coast in Oct 2006 compared to Feb 2007 as the stratification supports the IW activity. In the case of Feb 2007, the maximum IW energy is dampened sharply, and the rationale is two-fold. The first one is less stratification of the coastal waters and secondly is the presence of seasonal temperature inversion near the coast. These two factors are primarily responsible for the sharp decline of the energy over this region.

Origin and characteristics of discharge at San Marcos Springs, south-central Texas

USGS Publications Warehouse

Musgrove, MaryLynn; Crow, Cassi L.

2013-01-01

The Edwards aquifer in south-central Texas is one of the most productive aquifers in the Nation and is the primary source of water for the rapidly growing San Antonio area. Springs issuing from the Edwards aquifer provide habitat for several threatened and endangered species, serve as locations for recreational activities, and supply downstream users. Comal Springs and San Marcos Springs are major discharge points for the Edwards aquifer, and their discharges are used as thresholds in groundwater management strategies. Regional flow paths originating in the western part of the aquifer are generally understood to supply discharge at Comal Springs. In contrast, the hydrologic connection of San Marcos Springs with the regional Edwards aquifer flow system is less understood. During November 2008–December 2010, the U.S. Geological Survey, in cooperation with the San Antonio Water System, collected and analyzed hydrologic and geochemical data from springs, groundwater wells, and streams to gain a better understanding of the origin and characteristics of discharge at San Marcos Springs. During the study, climatic and hydrologic conditions transitioned from exceptional drought to wetter than normal. The wide range of hydrologic conditions that occurred during this study—and corresponding changes in surface-water, groundwater and spring discharge, and in physicochemical properties and geochemistry—provides insight into the origin of the water discharging from San Marcos Springs. Three orifices at San Marcos Springs (Deep, Diversion, and Weissmuller Springs) were selected to be representative of larger springs at the spring complex. Key findings include that discharge at San Marcos Springs was dominated by regional recharge sources and groundwater flow paths and that different orifices of San Marcos Springs respond differently to changes in hydrologic conditions; Deep Spring was less responsive to changes in hydrologic conditions than were Diversion Spring and Weissmuller Spring. Also, San Marcos Springs discharge is influenced by mixing with a component of saline groundwater.

Numerical study of groundwater flow cycling controlled by seawater/freshwater interaction in a coastal karst aquifer through conduit network using CFPv2.

PubMed

Xu, Zexuan; Hu, Bill X; Davis, Hal; Kish, Stephen

2015-11-01

In this study, a groundwater flow cycling in a karst springshed and an interaction between two springs, Spring Creek Springs and Wakulla Springs, through a subground conduit network are numerically simulated using CFPv2, the latest research version of MODFLOW-CFP (Conduit Flow Process). The Spring Creek Springs and Wakulla Springs, located in a marine estuary and 11 miles inland, respectively, are two major groundwater discharge spots in the Woodville Karst Plain (WKP), North Florida, USA. A three-phase conceptual model of groundwater flow cycling between the two springs and surface water recharge from a major surface creek (Lost Creek) was proposed in various rainfall conditions. A high permeable subground karst conduit network connecting the two springs was found by tracer tests and cave diving. Flow rate of discharge, salinity, sea level and tide height at Spring Creek Springs could significantly affect groundwater discharge and water stage at Wakulla Springs simultaneously. Based on the conceptual model, a numerical hybrid discrete-continuum groundwater flow model is developed using CFPv2 and calibrated by field measurements. Non-laminar flows in conduits and flow exchange between conduits and porous medium are implemented in the hybrid coupling numerical model. Time-variable salinity and equivalent freshwater head boundary conditions at the submarine spring as well as changing recharges have significant impacts on seawater/freshwater interaction and springs' discharges. The developed numerical model is used to simulate the dynamic hydrological process and quantitatively represent the three-phase conceptual model from June 2007 to June 2010. Simulated results of two springs' discharges match reasonably well to measurements with correlation coefficients 0.891 and 0.866 at Spring Creeks Springs and Wakulla Springs, respectively. The impacts of sea level rise on regional groundwater flow field and relationship between the inland springs and submarine springs are evaluated as well in this study. Copyright © 2015 Elsevier B.V. All rights reserved.

Numerical study of groundwater flow cycling controlled by seawater/freshwater interaction in a coastal karst aquifer through conduit network using CFPv2

NASA Astrophysics Data System (ADS)

Xu, Zexuan; Hu, Bill X.; Davis, Hal; Kish, Stephen

2015-11-01

In this study, a groundwater flow cycling in a karst springshed and an interaction between two springs, Spring Creek Springs and Wakulla Springs, through a subground conduit network are numerically simulated using CFPv2, the latest research version of MODFLOW-CFP (Conduit Flow Process). The Spring Creek Springs and Wakulla Springs, located in a marine estuary and 11 miles inland, respectively, are two major groundwater discharge spots in the Woodville Karst Plain (WKP), North Florida, USA. A three-phase conceptual model of groundwater flow cycling between the two springs and surface water recharge from a major surface creek (Lost Creek) was proposed in various rainfall conditions. A high permeable subground karst conduit network connecting the two springs was found by tracer tests and cave diving. Flow rate of discharge, salinity, sea level and tide height at Spring Creek Springs could significantly affect groundwater discharge and water stage at Wakulla Springs simultaneously. Based on the conceptual model, a numerical hybrid discrete-continuum groundwater flow model is developed using CFPv2 and calibrated by field measurements. Non-laminar flows in conduits and flow exchange between conduits and porous medium are implemented in the hybrid coupling numerical model. Time-variable salinity and equivalent freshwater head boundary conditions at the submarine spring as well as changing recharges have significant impacts on seawater/freshwater interaction and springs' discharges. The developed numerical model is used to simulate the dynamic hydrological process and quantitatively represent the three-phase conceptual model from June 2007 to June 2010. Simulated results of two springs' discharges match reasonably well to measurements with correlation coefficients 0.891 and 0.866 at Spring Creeks Springs and Wakulla Springs, respectively. The impacts of sea level rise on regional groundwater flow field and relationship between the inland springs and submarine springs are evaluated as well in this study.

Geochemical Investigation of Source Water to Cave Springs, Great Basin National Park, White Pine County, Nevada

USGS Publications Warehouse

Prudic, David E.; Glancy, Patrick A.

2009-01-01

Cave Springs supply the water for the Lehman Caves Visitor Center at Great Basin National Park, which is about 60 miles east of Ely, Nevada, in White Pine County. The source of water to the springs was investigated to evaluate the potential depletion caused by ground-water pumping in areas east of the park and to consider means to protect the supply from contamination. Cave Springs are a collection of several small springs that discharge from alluvial and glacial deposits near the contact between quartzite and granite. Four of the largest springs are diverted into a water-collection system for the park. Water from Cave Springs had more dissolved strontium, calcium, and bicarbonate, and a heavier value of carbon-13 than water from Marmot Spring at the contact between quartzite and granite near Baker Creek campground indicating that limestone had dissolved into water at Cave Springs prior to discharging. The source of the limestone at Cave Springs was determined to be rounded gravels from a pit near Baker, Nevada, which was placed around the springs during the reconstruction of the water-collection system in 1996. Isotopic compositions of water at Cave Springs and Marmot Spring indicate that the source of water to these springs primarily is from winter precipitation. Mixing of water at Cave Springs between alluvial and glacial deposits along Lehman Creek and water from quartzite is unlikely because deuterium and oxygen-18 values from a spring discharging from the alluvial and glacial deposits near upper Lehman Creek campground were heavier than the deuterium and oxygen-18 values from Cave Springs. Additionally, the estimated mean age of water determined from chlorofluorocarbon concentrations indicates water discharging from the spring near upper Lehman Creek campground is younger than that discharging from either Cave Springs or Marmot Spring. The source of water at Cave Springs is from quartzite and water discharges from the springs on the upstream side of the contact between quartzite and granite where the alluvial and glacial deposits are thin. Consequently, the potential for depletion of discharge at Cave Springs from ground-water pumping in Snake Valley east of the park is less than if the source of water was from alluvial and glacial deposits or carbonate rocks, which would be more directly connected to downstream pumping sites in Snake Valley.

1. Photocopy of map (from The Virginia Springs, and the ...

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

1. Photocopy of map (from The Virginia Springs, and the Springs of the South and West by Moorman) No date 'MAP OF ROUTES AND DISTANCES TO THE VIRGINIA SPRINGS' - White Sulphur Springs, U.S. Route 60, White Sulphur Springs, Greenbrier County, WV

The effect of linear spring number at side load of McPherson suspension in electric city car

NASA Astrophysics Data System (ADS)

Budi, Sigit Setijo; Suprihadi, Agus; Makhrojan, Agus; Ismail, Rifky; Jamari, J.

2017-01-01

The function of the spring suspension on Mc Pherson type is to control vehicle stability and increase ride convenience although having tendencies of side load presence. The purpose of this study is to obtain simulation results of Mc Pherson suspension spring in the electric city car by using the finite element method and determining the side load that appears on the spring suspension. This research is conducted in several stages; they are linear spring designing models with various spring coil and spring suspension modeling using FEM software. Suspension spring is compressed in the vertical direction (z-axis) and at the upper part of the suspension springs will be seen the force that arises towards the x, y, and z-axis to simulate the side load arising on the upper part of the spring. The results of FEM simulation that the side load on the spring toward the x and y-axis which the value gets close to zero is the most stable spring.

A Preliminary Investigation of Caffeinated Alcohol Use During Spring Break.

PubMed

Linden-Carmichael, Ashley N; Lau-Barraco, Cathy

2016-06-06

Caffeinated alcoholic beverages (e.g., Red Bull and vodka) are popular but associated with negative consequences. CABs may be particularly popular during Spring Break, a potentially risky social event. We aimed to identify the prevalence of Spring Break caffeinated alcohol use, determine how caffeinated alcohol use Spring Break drinking habits differ from usual, and examine the association between Spring Break caffeinated alcohol use and alcohol-related problems. Data were collected from 95 college students during March of 2013 and 2014. Students completed questionnaires of their alcohol and caffeinated alcohol use before and during Spring Break and Spring Break alcohol-related problems. Approximately 54% of students used caffeinated alcohol during Spring Break. Spring Break caffeinated alcohol use was associated with more alcohol-related problems, even after controlling for other alcohol consumed and Spring Break vacation status. Caffeinated alcoholic beverages are commonly consumed during Spring Break and their use uniquely predicted harms. Prevention efforts placed on caffeinated alcoholic beverage users may be helpful in reducing Spring Break-related harms.

Open-ended projects in undergraduate optics and lasers courses

NASA Astrophysics Data System (ADS)

Hoyt, Chad

This talk will describe the format and experience of undergraduate Lasers and Optics courses at Bethel University. The courses, which include a rigorous lecture portion, are built on open-ended research projects that have a novel aspect. They begin with four weeks of small student groups rotating between several standard laser and optics laboratory exercises. These may include, for example, alignment and characterization of a helium neon laser and measurements with a Michelson interferometer or a scanning Fabry-Pérot optical cavity. During the following seven weeks of the course, student groups (2-4 people) choose and pursue research questions in the lab. Their work culminates in a group manuscript typeset in and a twenty-minute presentation to the class. Projects in the spring, 2014 Optics course included experiments with ultracold lithium atoms in a magneto-optical trap, optical tweezers, digital holography and adaptive optics. Projects in the spring, 2015 Lasers course included ultrafast optics with a mode-locked erbium fiber laser, quantum optics, surface plasmon lasers (led by Nathan Lindquist) and a low-cost, near-infrared spectrometer. Several of these projects are related to larger scale, funded research in the physics department. The format and experience in Lasers and Optics is representative of other upper-level courses at Bethel, including Fluid Mechanics and Computer Methods. A physics education research group from the University of Colorado evaluated the spring, 2015 Lasers course. They focused on student experimental attitudes and measurements of student project ownership.

Plates and shells containing a surface crack under general loading conditions

NASA Technical Reports Server (NTRS)

Joseph, Paul F.; Erdogan, Fazil

1987-01-01

Various through and part-through crack problems in plates and shells are considered. The line-spring model of Rice and Levy is generalized to the skew-symmetric case to solve surface crack problems involving mixed-mode, coplanar crack growth. Compliance functions are introduced which are valid for crack depth to thickness ratios at least up to .95. This includes expressions for tension and bending as well as expressions for in-plane shear, out-of-plane shear, and twisting. Transverse shear deformation is taken into account in the plate and shell theories and this effect is shown to be important in comparing stress intensity factors obtained from the plate theory with three-dimensional solutions. Stress intensity factors for cylinders obtained by the line-spring model also compare well with three-dimensional solution. By using the line-spring approach, stress intensity factors can be obtained for the through crack and for part-through crack of any crack front shape, without recalculation integrals that take up the bulk of the computer time. Therefore, parameter studies involving crack length, crack depth, shell type, and shell curvature are made in some detail. The results will be useful in brittle fracture and in fatigue crack propagation studies. All problems considered are of the mixed boundary value type and are reducted to strongly singular integral equations which make use of the finite-part integrals of Hadamard. The equations are solved numerically in a manner that is very efficient.

Leg stiffness and stride frequency in human running.

PubMed

Farley, C T; González, O

1996-02-01

When humans and other mammals run, the body's complex system of muscle, tendon and ligament springs behaves like a single linear spring ('leg spring'). A simple spring-mass model, consisting of a single linear leg spring and a mass equivalent to the animal's mass, has been shown to describe the mechanics of running remarkably well. Force platform measurements from running animals, including humans, have shown that the stiffness of the leg spring remains nearly the same at all speeds and that the spring-mass system is adjusted for higher speeds by increasing the angle swept by the leg spring. The goal of the present study is to determine the relative importance of changes to the leg spring stiffness and the angle swept by the leg spring when humans alter their stride frequency at a given running speed. Human subjects ran on treadmill-mounted force platform at 2.5ms-1 while using a range of stride frequencies from 26% below to 36% above the preferred stride frequency. Force platform measurements revealed that the stiffness of the leg spring increased by 2.3-fold from 7.0 to 16.3 kNm-1 between the lowest and highest stride frequencies. The angle swept by the leg spring decreased at higher stride frequencies, partially offsetting the effect of the increased leg spring stiffness on the mechanical behavior of the spring-mass system. We conclude that the most important adjustment to the body's spring system to accommodate higher stride frequencies is that leg spring becomes stiffer.

Integrated geophysical investigations of Main Barton Springs, Austin, Texas, USA

NASA Astrophysics Data System (ADS)

Saribudak, By Mustafa; Hauwert, Nico M.

2017-03-01

Barton Springs is a major discharge site for the Barton Springs Segment of the Edwards Aquifer and is located in Zilker Park, Austin, Texas. Barton Springs actually consists of at least four springs. The Main Barton Springs discharges into the Barton Springs pool from the Barton Springs fault and several outlets along a fault, from a cave, several fissures, and gravel-filled solution cavities on the floor of the pool west of the fault. Surface geophysical surveys [resistivity imaging, induced polarization (IP), self-potential (SP), seismic refraction, and ground penetrating radar (GPR)] were performed across the Barton Springs fault and at the vicinity of the Main Barton Springs in south Zilker Park. The purpose of the surveys was two-fold: 1) locate the precise location of submerged conduits (caves, voids) carrying flow to Main Barton Springs; and 2) characterize the geophysical signatures of the fault crossing Barton Springs pool. Geophysical results indicate significant anomalies to the south of the Barton Springs pool. A majority of these anomalies indicate a fault-like pattern, in front of the south entrance to the swimming pool. In addition, resistivity and SP results, in particular, suggest the presence of a large conduit in the southern part of Barton Springs pool. The groundwater flow-path to the Main Barton Springs could follow the locations of those resistivity and SP anomalies along the newly discovered fault, instead of along the Barton Springs fault, as previously thought.

Based on Artificial Neural Network to Realize K-Parameter Analysis of Vehicle Air Spring System

NASA Astrophysics Data System (ADS)

Hung, San-Shan; Hsu, Chia-Ning; Hwang, Chang-Chou; Chen, Wen-Jan

2017-10-01

In recent years, because of the air-spring control technique is more mature, that air- spring suspension systems already can be used to replace the classical vehicle suspension system. Depend on internal pressure variation of the air-spring, thestiffnessand the damping factor can be adjusted. Because of air-spring has highly nonlinear characteristic, therefore it isn’t easy to construct the classical controller to control the air-spring effectively. The paper based on Artificial Neural Network to propose a feasible control strategy. By using offline way for the neural network design and learning to the air-spring in different initial pressures and different loads, offline method through, predict air-spring stiffness parameter to establish a model. Finally, through adjusting air-spring internal pressure to change the K-parameter of the air-spring, realize the well dynamic control performance of air-spring suspension.

Uneven drive rates of the scanning telescope: Apollo 16 mission

NASA Technical Reports Server (NTRS)

1972-01-01

An investigation was made into the cause or causes of uneven drive rates during operation of the Apollo 16 scanning telescope. It was suggested that such erratic behavior was caused by either changes in the characteristics noise level of the optics counter on the panels or the repositioning process by the computer or zero optics mode. Test results show the anomaly was not caused by either of the above suggestions, instead they were caused by a broken socket spring in the telescope harness. New harnesses will be manufactured for future flights.

Impact Testing of Explosives and Propellants

DTIC Science & Technology

1992-06-01

in order to better understand the test results. The physical behavior of tile drop weight impact test can be modeled on a computer with all of the...SPRING ELEMENTS OF SIMPLIFIED IMPACT MACHINE A-4 NSV’CDDITR-92/280 4 j DISTRIBUTION Copies C~e ATTN ONR 1132P (R MILLER ) 1 ATTN 6-A-145 1 ONT2OT(L V...LIBRARY OF CONGRESS (J W FORBES) 1 WASHINGTON DC 20540 (R11 GUIRGUIS ) 1 (P K GUSTAVSON) I INTERNAL DISTRIBUTION (R N HAY) ! E231 2 (It D JONES) 1 E232 3 (K

Streamflow model of Wisconsin River for estimating flood frequency and volume

USGS Publications Warehouse

Krug, William R.; House, Leo B.

1980-01-01

The 100-year flood peak at Wisconsin Dells, computed from the simulated, regulated streamflow data for the period 1915-76, is 82,000 cubic feet per second, including the effects of all the reservoirs in the river system, as they are currently operated. It also includes the effects of Lakes Du Bay, Petenwell, and Castle Rock which are significant for spring floods but are insignificant for summer or fall floods because they are normally maintained nearly full in the summer and fall and have very little storage for floodwaters. (USGS)

Chemical, isotopic, and gas compositions of selected thermal springs in Arizona, New Mexico, and Utah

USGS Publications Warehouse

Mariner, R.H.; Presser, T.S.; Evans, William C.

1977-01-01

Twenty-seven thermal springs in Arizona, New Mexico, and Utah were sampled for detailed chemical and isotopic analysis. The springs issue sodium chloride, sodium bicarbonate, or sodium mixed-anion waters of near neutral (6.2) to alkaline (9.2) pH. High concentrations of fluoride, more than 8 milligrams per liter, occur in Arizona in waters from Gillard Hot Springs, Castle Hot Springs, and the unnamed spring of Eagle Creek, and in New Mexico from springs along the Gila River. Deuterium compositions of the thermal waters cover the same range as those expected for meteoric waters in the respective areas. The chemical compositions of the thermal waters indicate that Thermo Hot Springs in Utah and Gillard Hot Springs in Arizona represent hydrothermal systems which are at temperatures higher than 125 deg C. Estimates of subsurface temperature based on the quartz and Na-K-Ca geothermometer differ by up to 60 deg C for Monroe, Joseph, Red Hill, and Crater hot springs in Utah. Similar conflicting estimates of aquifer temperature occur for Verde Hot Springs, the springs near Clifton and Coolidge Dam, in Arizona; and the warm springs near San Ysidro, Radium Hot Springs, and San Francisco Hot Springs, in New Mexico. Such disparities could result from mixing, precipitation of calcium carbonate, or perhaps appreciable concentrations of magnesium. (Woodard-USGS)

Spatial Characteristics of Geothermal Spring Temperatures and Discharge Rates in the Tatun Volcanic Area, Taiwan

NASA Astrophysics Data System (ADS)

Jang, C. S.; Liu, C. W.

2014-12-01

The Tatun volcanic area is the only potential volcanic geothermal region in the Taiwan island, and abundant in hot spring resources owing to stream water mixing with fumarolic gases. According to the Meinzer's classification, spring temperatures and discharge rates are the most important properties for characterizing spring classifications. This study attempted to spatially characterize spring temperatures and discharge rates in the Tatun volcanic area, Taiwanusing indicator kriging (IK). First, data on spring temperatures and discharge rates, which were collected from surveyed data of the Taipei City Government, were divided into high, moderate and low categories according to spring classification criteria, and the various categories were regarded as estimation thresholds. Then, IK was adopted to model occurrence probabilities of specified temperatures and discharge rates in springs, and to determine their classifications based on estimated probabilities. Finally, nine combinations were obtained from the classifications of temperatures and discharge rates in springs. Moreover, the combinations and features of spring water were spatially quantified according to seven sub-zones of spring utilization. A suitable and sustainable development strategy of the spring area was proposed in each sub-zone based on probability-based combinations and features of spring water.The research results reveal that the probability-based classifications using IK provide an excellent insight in exploring the uncertainty of spatial features in springs, and can provide Taiwanese government administrators with detailed information on sustainable spring utilization and conservation in the overexploited spring tourism areas. The sub-zones BT (Beitou), RXY (Rd. Xingyi), ZSL (Zhongshanlou) and LSK (Lengshuikeng) with high or moderate discharge rates are suitable to supply spring water for tourism hotels.Local natural hot springs should be planned in the sub-zones DBT (Dingbeitou), ZSL, XYK (Xiayoukeng), and MC (Macao) with low discharge rates, and low or moderate temperatures, particularly in riverbeds or valleys.Keywords: Spring; Temperature; Discharge rate; Indicator kriging; Uncertainty

77 FR 30187 - Amendment of Class E Airspace; Rock Springs, WY

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-22

...-0131; Airspace Docket No. 12-ANM-2] Amendment of Class E Airspace; Rock Springs, WY AGENCY: Federal... Rock Springs-Sweetwater County Airport, Rock Springs, WY. Decommissioning of the Rock Springs Tactical... Rock Springs, WY (77 FR 11796). Interested parties were invited to participate in this rulemaking...

49 CFR 229.65 - Spring rigging.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Spring rigging. 229.65 Section 229.65....65 Spring rigging. (a) Protective construction or safety hangers shall be provided to prevent spring planks, spring seats or bolsters from dropping to track structure in event of a hanger or spring failure...

49 CFR 229.65 - Spring rigging.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Spring rigging. 229.65 Section 229.65....65 Spring rigging. (a) Protective construction or safety hangers shall be provided to prevent spring planks, spring seats or bolsters from dropping to track structure in event of a hanger or spring failure...

49 CFR 229.65 - Spring rigging.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Spring rigging. 229.65 Section 229.65....65 Spring rigging. (a) Protective construction or safety hangers shall be provided to prevent spring planks, spring seats or bolsters from dropping to track structure in event of a hanger or spring failure...

49 CFR 229.65 - Spring rigging.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Spring rigging. 229.65 Section 229.65....65 Spring rigging. (a) Protective construction or safety hangers shall be provided to prevent spring planks, spring seats or bolsters from dropping to track structure in event of a hanger or spring failure...

49 CFR 229.65 - Spring rigging.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Spring rigging. 229.65 Section 229.65....65 Spring rigging. (a) Protective construction or safety hangers shall be provided to prevent spring planks, spring seats or bolsters from dropping to track structure in event of a hanger or spring failure...

Effects of well discharges on hydraulic heads in and spring discharges from the Geothermal Aquifer System in the Bruneau area, Owyhee County, southwestern Idaho

USGS Publications Warehouse

Berenbrock, Charles

1993-01-01

substantially less in late summer than in the spring. A hydraulic head/spring discharge relation was developed for two sites at Indian Bathtub Spring and a nearby test hole. The relation for Indian Bathtub Spring indicated that a spring discharge of 2,400 gallons per minute would relate to a hydraulic head of about 2,708 feet at the spring, which is about 34 feet higher than the head at zero spring discharge.

Double plication for spring-mediated intestinal lengthening of a defunctionalized Roux limb.

PubMed

Dubrovsky, Genia; Huynh, Nhan; Thomas, Anne-Laure; Shekherdimian, Shant; Dunn, James C Y

2017-12-26

Spring-mediated distraction enterogenesis has been shown to increase the length of an intestinal segment. The goal of this study is to use suture plication to confine a spring within an intestinal segment while maintaining luminal patency to the rest of the intestine. Juvenile mini-Yucatan pigs underwent placement of nitinol springs within a defunctionalized Roux limb of jejunum. A 20 French catheter was passed temporarily, and sutures were used to plicate the intestinal wall around the catheter at both ends of the encapsulated spring. Uncompressed springs placed in plicated segments and springs placed in nonplicated segments served as controls. The intestine was examined approximately 3 weeks after spring placement. In the absence of plication, springs passed through the intestine within a week. Double plication allowed the spring to stay within the Roux limb for 3 weeks. Compared to uncompressed springs that showed no change in the length of plicated segments, compressed springs caused a significant 1.7-fold increase in the length of plicated segments. Intestinal plication is an effective method to confine endoluminal springs. The confined springs could lengthen intestine that maintains luminal patency. This approach may be useful to lengthen intestine in patients with short bowel syndrome. Level I Experimental Study. Copyright © 2018. Published by Elsevier Inc.

Biogeographic patterns of desert springs in the Great Basin with an emphasis on regional aquifer thermal springs as refugia for vulnerable crenobiotic species

NASA Astrophysics Data System (ADS)

Forrest, M.; Sada, D. W.; Norris, R. D.

2013-12-01

The desert springs of the Great Basin Region in western North America provide ideal systems to study biogeographic and evolutionary patterns. In arid regions, springs are biodiversity hotspots because they often provide the sole source of water for the biota within and around them. In the Great Basin, springs provide critical habitat for diverse and extensive crenobiotic flora and fauna comprising over 125 endemic species. These aquatic environments represent island ecosystems surrounded by seas of desert, and researchers have compiled large databases of their biota and chemistry. Consequently, desert springs are excellent systems for biogeographic studies and multivariate statistical analyses of relationships between the chemical and physical characteristics of the springs and the biological communities that they support. The purpose of this study is to elucidate the relationships between the physicochemical characteristics of springs and their biota using multivariate statistical analyses to characterize 1325 springs, including regional aquifer springs, local aquifer cold springs and geothermal springs. The analyses reveal that regional aquifer thermal springs harbor disproportionate numbers of crenobiotic species including endemic gastropods, fishes, and aquatic insects. However, these regional aquifer springs also contain significantly more introduced species than cold and geothermal local aquifer springs. Springs are threatened by anthropogenic impacts including groundwater depletion and pollution, alteration of flow regimes, and the introduction of exotic species. In this study, one of the major factors that distinguished regional aquifer thermal springs from cold and geothermal local aquifer springs was the higher number of introduced species found in regional aquifer springs. This may be due to the influences of the same physicochemical characteristics that allow regional aquifer springs to serve as refugia for endemic species--species that are able to gain access to these environments and cope with their extreme physicochemical characteristics may be provided with refuge from extinction. The disproportionate number of endemic crenobiotic species found in regional aquifer thermal springs, as well as in some local aquifer geothermal springs, within the Great Basin strongly suggests that these hydrothermal habitats represent important biodiversity hotspots, and efforts to conserve and restore these unique ecosystems should be a major priority to ensure that the valuable information that these species can provide is not lost forever.

Comparison of Estimated Areas Contributing Recharge to Selected Springs in North-Central Florida by Using Multiple Ground-Water Flow Models

USGS Publications Warehouse

Shoemaker, W. Barclay; O'Reilly, Andrew M.; Sepúlveda, Nicasio; Williams, Stanley A.; Motz, Louis H.; Sun, Qing

2004-01-01

Areas contributing recharge to springs are defined in this report as the land-surface area wherein water entering the ground-water system at the water table eventually discharges to a spring. These areas were delineated for Blue Spring, Silver Springs, Alexander Springs, and Silver Glen Springs in north-central Florida using four regional ground-water flow models and particle tracking. As expected, different models predicted different areas contributing recharge. In general, the differences were due to different hydrologic stresses, subsurface permeability properties, and boundary conditions that were used to calibrate each model, all of which are considered to be equally feasible because each model matched its respective calibration data reasonably well. To evaluate the agreement of the models and to summarize results, areas contributing recharge to springs from each model were combined into composite areas. During 1993-98, the composite areas contributing recharge to Blue Spring, Silver Springs, Alexander Springs, and Silver Glen Springs were about 130, 730, 110, and 120 square miles, respectively. The composite areas for all springs remained about the same when using projected 2020 ground-water withdrawals.

The National Astronomy Consortium (NAC) - Overview

NASA Astrophysics Data System (ADS)

Sheth, Kartik; Mills, Elisabeth A. C.; Hooper, Eric; National Astronomy Consortium

2015-01-01

The National Astronomy Consortium (NAC; see https://sites.google.com/site/nraonac/) is a growing national partnership between majority and minority universities and institutions with the goal of increasing the numbers of under-represented minorities and students who might otherwise be overlooked by the traditional academic pipeline into STEM, or related, careers. The NAC model is based on the successful 'Posse Foundation' model for undergraduate success and incorporates all its major components: pre-training of cohorts to prepare them for the research experience, joint weekly cohort activities throughout the research summer, peer- and multiple mentoring, weekly discussion of various aspects of professional and career development, continued engagement of students in science after return to home institution and lifelong mentoring. The mentors also form a cohort, exchanging information and learning from each other. With its partner institutions, the NAC aims to build a complete pipeline from undergraduate through career for the next generation of scientists and engineers. Our annual goal is to create two to three cohorts of four to five students at each site (currently NRAO-Charlottesville, NRAO-Socorro and U. Wisconsin - Madison). Recruitment occurs in the fall semester with seminars and colloquia in partnership with faculty at the minority serving institutions and the GRAD-MAP program at the University of Maryland. In this talk we describe in detail all the components of the NAC and report on our progress. We are keen to interact and partner with new universities and institutions and encourage them to contact the NAC at nac4stem@googlegroups.com.

Fall-to-Fall Testing versus Spring-to-Spring Testing: What Is the Impact on a Local Community's Chapter 1 Evaluation?

ERIC Educational Resources Information Center

Bushner, Diane E.

The impact of a decision by a local program under Chapter 1, the federally funded program of financial assistance to special educational needs of children, to test students fall-to-fall or spring-to-spring was studied. Students enrolled in a Chapter 1 reading program in 1988-89 were tested on a fall-to-spring basis, a spring-to-spring basis, and a…

Morphological parameters for implantation of the screwless spring loop dynamic posterior spinous process stabilizing system.

PubMed

Song, Geun Soo; Lee, Yeon Soo

2015-07-01

This study aimed to quantify morphological characteristics of the posterior lumbar spinous process, which may affect stable implantation of screwless wire spring loops. Virtual implantations of a screwless wire spring loop onto pairs of lumbar spinous processes were performed for computed tomography (CT)-derived three-dimensional vertebral models of 40 Korean subjects. Morphological parameters of lumbar vertebrae 1 through 5 (L1-L5) were measured with regard to bone-implant interference. In males, the transspinous process fixation lengths decreased from 57.8±3.0mm to 48.8±3.2mm as the lumbar joints descend from L1-L2 to L4-L5, with those in females about 4.1±0.4mm shorter (p<0.05) than in males through all lumbar joints. The fixation angle on the sagittal plane varied from 105.0° to 101.3° relative to the transverse plane as the vertebrae descend. The clenched thickness in females was the least (6.7±1.2mm) for the L2 lower spinous process and the greatest (8.1±2.2mm) for the L4 upper spinous process; this was 1.0±10.3mm less than that for males at corresponding levels (p>0.05). The ratio of the spinous process clenched thickness to the transspinous fixation length increased from 0.133±0.016 to 0.196±0.076 for the upper spinous processes as the lumbar joints descend. The ratio of the spinous process clenched thickness to the transspinous fixation length varies, depending on gender and whether the clenched level is the upper or lower spinous process. These parameters related to the clenching fixation stability should be considered in development and implantations of the screwless wire spring loop. Copyright © 2015 Elsevier GmbH. All rights reserved.

Assessing satellite-derived start-of-season measures in the conterminous USA

USGS Publications Warehouse

Schwartz, Mark D.; Reed, Bradley C.; White, Michael A.

2002-01-01

National Oceanic and Atmospheric Administration (NOAA)-series satellites, carrying advanced very high-resolution radiometer (AVHRR) sensors, have allowed moderate resolution (1 km) measurements of the normalized difference vegetation index (NDVI) to be collected from the Earth's land surfaces for over 20 years. Across the conterminous USA, a readily accessible and decade-long data set is now available to study many aspects of vegetation activity in this region. One feature, the onset of deciduous plant growth at the start of the spring season (SOS) is of special interest, as it appears to be crucial for accurate computation of several important biospheric processes, and a sensitive measure of the impacts of global change. In this study, satellite-derived SOS dates produced by the delayed moving average (DMA) and seasonal midpoint NDVI (SMN) methods, and modelled surface phenology (spring indices, SI) were compared at widespread deciduous forest and mixed woodland sites during 1990–93 and 1995–99, and these three measures were also matched to native species bud-break data collected at the Harvard Forest (Massachusetts) over the same time period. The results show that both SOS methods are doing a modestly accurate job of tracking the general pattern of surface phenology, but highlight the temporal limitations of biweekly satellite data. Specifically, at deciduous forest sites: (1) SMN SOS dates are close in time to SI first bloom dates (average bias of +0.74 days), whereas DMA SOS dates are considerably earlier (average bias of −41.24 days) and also systematically earlier in late spring than in early spring; (2) SMN SOS tracks overall yearly trends in deciduous forests somewhat better than DMA SOS, but with larger average error (MAEs 8.64 days and 7.37 days respectively); and (3) error in both SOS techniques varies considerably by year. Copyright © 2002 Royal Meteorological Society.

Biomechanical Analysis of a Filiform Mechanosensory Hair Socket of Crickets.

PubMed

Joshi, Kanishka; Mian, Ahsan; Miller, John

2016-08-01

Filiform mechanosensory hairs of crickets are of great interest to engineers because of the hairs' highly sensitive response to low-velocity air-currents. In this study, we analyze the biomechanical properties of filiform hairs of the cercal sensory system of a common house cricket. The cercal sensory system consists of two antennalike appendages called cerci that are situated at the rear of the cricket's abdomen. Each cercus is covered with 500-750 flow sensitive filiform mechanosensory hairs. Each hair is embedded in a complex viscoelastic socket that acts as a spring and dashpot system and guides the movement of the hair. When a hair deflects due to the drag force induced on its length by a moving air-current, the spiking activity of the neuron that innervates the hair changes and the combined spiking activity of all hairs is extracted by the cercal sensory system. Filiform hairs have been experimentally studied by researchers, though the basis for the hairs' biomechanical characteristics is not fully understood. The socket structure has not been analyzed experimentally or theoretically from a mechanical standpoint, and the characterization that exists is mathematical in nature and only provides a very rudimentary approximation of the socket's spring nature. This study aims to understand and physically characterize the socket's behavior and interaction with the filiform hair by examining hypotheses about the hair and socket biomechanics. A three-dimensional computer-aided design (CAD) model was first created using confocal microscopy images of the hair and socket structure of the cricket, and then finite-element analyses (FEAs) based on the physical conditions that the insect experiences were simulated. The results show that the socket can act like a spring; however, it has two-tier rotational spring constants during pre- and postcontacts of iris and hair bulge due to its constitutive nonstandard geometric shapes.

Alabama NASA EPSCoR Preparation Grant Program: Grant No. NCC5-391

NASA Technical Reports Server (NTRS)

Gregory, John C.

2003-01-01

The funded research projects under the Experimental Program to Stimulate Cooperative Research (EPSCoR) grant program and the student fellowship awards are summarized in this report. The projects include: 1) Crystallization of Dehydratase/DcoH: A Target in Lung Disease; 2) Measuring Velocity Profiles in Liquid Metals using an Ultrasonic Doppler Velocimeter; 3) Synthesis, Structure, and Properties of New Thermoelectric Materials; 4) Computational Determination of Structures and Reactivity of Phenol-Formaldehyde Resins; 5) Synthesis of Microbial Polyesters in the NASA Bioreactor; 6) Visualization of Flow-Fields in Magnetocombustion; 7) Synthesis of Fluorescent Saccharide Derivatives. The student fellowship awards include: 1) Distributed Fusion of Satellite Images; 2) Study of the Relationship between Urban Development, Local Climate, and Water Quality for the Atlanta, Georgia Metrop; 3) Computer Simulation of the Effectiveness of a Spring-Loaded Exercise Device.

Large deflection elastic-plastic dynamic response of stiffened shells of revolution

NASA Technical Reports Server (NTRS)

Stricklin, J. A.; Haisler, W. E.; Vonriesemann, W. A.; Leick, R. D.; Hunsaker, B.; Saczalski, K. J.

1972-01-01

The formulation and check out porblems for a computer code DYNAPLAS, which analyzes the large deflection elastic-plastic dynamic response of stiffened shells of revolution, are presented. The formulation for special discretization is by the finite element method with finite differences being used for the evaluation of the pseudo forces due to material and geometric nonlinearities. Time integration is by the Houbolt method. The stiffeners may be due to concentrated or distributed eccentric rings and spring supports at arbitrary angles around the circumference of the elements. Check out porblems include the comparison of solutions from DYNAPLAS with experimental and other computer solutions for rings, conical and cylindrical shells and a curved panel. A hypothetical submarine including stiffeners and missile tube is studied under a combination of hydrostatic and dynamically applied asymmetrical pressure loadings.

Timber type separability in Southeastern United States on LANDSAT-1 MSS data

NASA Technical Reports Server (NTRS)

Kan, E. P.; Dillman, R. D.

1975-01-01

A quantitative, computer-aided study was made on the spectral separability of timber types and condition classes in the Southeastern United States, using LANDSAT-1 multispectral scanner data. It was concluded that LANDSAT-1 could be used effectively to discriminate the gross forest features of softwood, hardwood, and regeneration. The only significant detectable age difference would be between an established forest versus a young (or denuded) forest. The red or near infrared bands would be better for discrimination; phenological early and late spring data would be better than winter. And a temporal analysis would be superior to single-season analysis. Lastly, two spectral bands would be most cost effective for computer analysis. The study site was Sam Houston National Forest of East Texas, a typical forest in the Flatwoods Zone, Southern Region, U. S. Forest Service.

Spring distributions and relationships with land cover and hydrogeologic strata in a karst landscape in Winona County, Minnesota, USA

USGS Publications Warehouse

Williams, M.A.; Vondracek, B.

2010-01-01

Karst aquifers are important groundwater resources, but are vulnerable to contamination due to relatively rapid subsurface transport. Springs, points where the landscape and water table intersect and cold groundwater discharges, link aquifer systems with land surfaces and water bodies. As such, in many regions, they are critical to the viability of lakes, streams and cold-water fish communities. An understanding of where springs are located is important to watershed, fishery and environmental management efforts in karst regions. To better understand spatial distribution of springs and as a potential method for identifying variables that characterize locations of springs for improved land and watershed management, a nearest-neighbor analysis and a discriminant function analysis (DFA) of springs were conducted in Winona County, Minnesota USA, a karst landscape. Nearestneighbor analysis examined the spatial spring distribution. Twenty-two variables describing the locations of springs were analyzed to ascertain their ability to discriminate correct aquifer unit or bedrock unit classification for each spring. Springs were clumped with the highest densities in the lowest elevations. Springs were correctly assigned to aquifer units and bedrock units with eight and 11 landscape variables, respectively. Forest land cover was the only land cover type contributing to spring discrimination. Consideration of upland human activities, particularly in forested areas, on spring discharge along with a better understanding of characteristics describing spring locations could lead to better management activities that locate and protect springs and their important contributions to regional ecohydrology. ?? 2010 Springer-Verlag.

Spring distribution in Winona County, Minnesota, USA and the relationship with geologic strata in a karst landscape

USGS Publications Warehouse

Vondracek, Bruce C.; Williams, Mary A.

2010-01-01

Karst aquifers are important groundwater resources, but are vulnerable to contamination due to relatively rapid subsurface transport. Springs, points where the landscape and water table intersect and cold groundwater discharges, link aquifer systems with land surfaces and water bodies. As such, in many regions, they are critical to the viability of lakes, streams and cold-water fish communities. An understanding of where springs are located is important to watershed, fishery and environmental management efforts in karst regions. To better understand spatial distribution of springs and as a potential method for identifying variables that characterize locations of springs for improved land and watershed management, a nearest-neighbor analysis and a discriminant function analysis (DFA) of springs were conducted in Winona County, Minnesota, USA, a karst landscape. Nearest-neighbor analysis examined the spatial spring distribution. Twenty-two variables describing the locations of springs were analyzed to ascertain their ability to discriminate correct aquifer unit or bedrock unit classification for each spring. Springs were clumped with the highest densities in the lowest elevations. Springs were correctly assigned to aquifer units and bedrock units with eight and 11 landscape variables, respectively. Forest land cover was the only land cover type contributing to spring discrimination. Consideration of upland human activities, particularly in forested areas, on spring discharge along with a better understanding of characteristics describing spring locations could lead to better management activities that locate and protect springs and their important contributions to regional ecohydrology.

Hydrochemical Characteristics and Formation of the Saline or Salty Springs in Eastern Sichuan Basin of China

NASA Astrophysics Data System (ADS)

Zhou, X.

2017-12-01

Saline or salty springs provide important information on the hydrogeochemical processes and hydrology within subsurface aquifers. More than 20 saline and salty springs occur in the core of anticlines in the eastern Sichuan Basin in southwestern China where the Lower and Middle Triassic carbonates outcrop. Water samples of 8 saline and salty springs (including one saline hot spring) were collected for analyses of the major and minor constituents, trace elements and stable oxygen and hydrogen isotopes. The TDS of the springs range from 4 to 83 g/L, and they are mainly of Cl-Na type. Sr, Ba and Li are the predominant trace elements. The δ2H and δ18O of the water samples indicate that they are of meteoric origin. The source of salinity of the springs originates from dissolution of minerals in the carbonates, including halite, gypsum, calcite and dolomite. The formation mechanism of the springs is that groundwater receives recharge from infiltration of precipitation, undergoes shallow or deep circulation in the core of the anticline and incongruent dissolution of the salt-bearing carbonates occurs, and emerges in the river valley in the form of springs with relatively high TDS. The 8 springs can be classified into 4 springs of shallow groundwater circulation and 4 springs of deep groundwater circulation according to the depth of groundwater circulation, 7 springs of normal temperature and 1 hot spring according to temperature. There are also 2 up-flow springs: the carbonate aquifers are overlain by relatively impervious sandstone and shale, groundwater may flows up to the ground surface through the local portion of the overlying aquiclude where fractures were relatively well developed, and emerges as an up-flow spring. Knowledge of the hydrochemical characteristics and the geneses of the saline and salty springs are of important significance for the utilization and preservation of the springs.

Three-dimensional visualization system as an aid for facial surgical planning

NASA Astrophysics Data System (ADS)

Barre, Sebastien; Fernandez-Maloigne, Christine; Paume, Patricia; Subrenat, Gilles

2001-05-01

We present an aid for facial deformities treatment. We designed a system for surgical planning and prediction of human facial aspect after maxillo-facial surgery. We study the 3D reconstruction process of the tissues involved in the simulation, starting from CT acquisitions. 3D iso-surfaces meshes of soft tissues and bone structures are built. A sparse set of still photographs is used to reconstruct a 360 degree(s) texture of the facial surface and increase its visual realism. Reconstructed objects are inserted into an object-oriented, portable and scriptable visualization software allowing the practitioner to manipulate and visualize them interactively. Several LODs (Level-Of- Details) techniques are used to ensure usability. Bone structures are separated and moved by means of cut planes matching orthognatic surgery procedures. We simulate soft tissue deformations by creating a physically-based springs model between both tissues. The new static state of the facial model is computed by minimizing the energy of the springs system to achieve equilibrium. This process is optimized by transferring informations like participation hints at vertex-level between a warped generic model and the facial mesh.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mendonça, João M.; Grimm, Simon L.; Grosheintz, Luc

We have designed and developed, from scratch, a global circulation model (GCM) named THOR that solves the three-dimensional nonhydrostatic Euler equations. Our general approach lifts the commonly used assumptions of a shallow atmosphere and hydrostatic equilibrium. We solve the “pole problem” (where converging meridians on a sphere lead to increasingly smaller time steps near the poles) by implementing an icosahedral grid. Irregularities in the grid, which lead to grid imprinting, are smoothed using the “spring dynamics” technique. We validate our implementation of spring dynamics by examining calculations of the divergence and gradient of test functions. To prevent the computational timemore » step from being bottlenecked by having to resolve sound waves, we implement a split-explicit method together with a horizontally explicit and vertically implicit integration. We validate our GCM by reproducing the Earth and hot-Jupiter-like benchmark tests. THOR was designed to run on graphics processing units (GPUs), which allows for physics modules (radiative transfer, clouds, chemistry) to be added in the future, and is part of the open-source Exoclimes Simulation Platform (www.exoclime.org).« less

Approximate analytical solutions to the double-stance dynamics of the lossy spring-loaded inverted pendulum.

PubMed

Shahbazi, Mohammad; Saranlı, Uluç; Babuška, Robert; Lopes, Gabriel A D

2016-12-05

This paper introduces approximate time-domain solutions to the otherwise non-integrable double-stance dynamics of the 'bipedal' spring-loaded inverted pendulum (B-SLIP) in the presence of non-negligible damping. We first introduce an auxiliary system whose behavior under certain conditions is approximately equivalent to the B-SLIP in double-stance. Then, we derive approximate solutions to the dynamics of the new system following two different methods: (i) updated-momentum approach that can deal with both the lossy and lossless B-SLIP models, and (ii) perturbation-based approach following which we only derive a solution to the lossless case. The prediction performance of each method is characterized via a comprehensive numerical analysis. The derived representations are computationally very efficient compared to numerical integrations, and, hence, are suitable for online planning, increasing the autonomy of walking robots. Two application examples of walking gait control are presented. The proposed solutions can serve as instrumental tools in various fields such as control in legged robotics and human motion understanding in biomechanics.

Recent (2003-05) water quality of Barton Springs, Austin, Texas, with emphasis on factors affecting variability

USGS Publications Warehouse

Mahler, Barbara J.; Garner, Bradley D.; Musgrove, MaryLynn; Guilfoyle, Amber L.; Rao, Mohan V.

2006-01-01

From 2003 to 2005, the U.S. Geological Survey, in cooperation with the Texas Commission on Environmental Quality, collected and analyzed water samples from the four springs (orifices) of Barton Springs in Austin, Texas (Upper, Main, Eliza, and Old Mill Springs), with the objective of characterizing water quality. Barton Springs is the major discharge point for the Barton Springs segment of the Edwards aquifer. A three-pronged sampling approach was used: physicochemical properties (including specific conductance and turbidity) were measured continuously; samples were collected from the four springs routinely every 2 weeks (during August-September 2003) to 3 weeks (during June 2004-June 2005) and analyzed for some or all major ions, nutrients, trace elements, soluble pesticides, and volatile organic compounds; and samples were collected from the four springs at more closely spaced intervals during the 2 weeks following two storms and analyzed for the same suite of constituents. Following the two storms, samples also were collected from five of the six major streams that provide recharge to Barton Springs. Spring discharge during both sample collection periods was above average (60 cubic feet per second or greater). Barton Springs was found to be affected by persistent low concentrations of atrazine (an herbicide), chloroform (a drinking-water disinfection by-product), and tetrachloroethene (a solvent). Increased recharge from the major recharging streams resulted in increased calcium, sulfate, atrazine, simazine, and tetrachloroethene concentrations and decreased concentrations of most other major ions, nitrate, and chloroform at one or more of the springs. These changes in concentration demonstrate the influence of water quality in recharging streams on water quality at the springs even during non-stormflow conditions. The geochemical compositions of the four springs indicate that Upper Spring is more contaminated and is influenced by a contributing flow path that is separate from those leading to other springs under all but stormflow conditions. Main, Eliza, and Old Mill Springs share at least one common flow path that contributes contaminants to the three springs. Old Mill Spring, however, is less affected by anthropogenic contaminants than the other springs and receives a greater component of water from a flow path whose geochemistry is influenced by water from the saline zone of the aquifer. At Main Spring, atrazine, simazine, chloroform, and tetrachloroethene concentrations increased following storms, describing breakthrough curves that peaked 2 days following rainfall; at Upper Spring, atrazine and simazine concentrations described breakthrough curves that peaked 1 day following rainfall. At both Main and Upper Springs, additional anthropogenic compounds were detected following storms. The geochemical response of the springs to recharge indicates that much of the transport occurs through conduits. When there is no flow in the recharging streams, ground water advects from the aquifer matrix into the conduits and is transported to the springs. When there is flow in the streams, recharge through the streambeds directly enters the conduit system and is transported to the springs. Following storms, surface runoff recharges through both interstream recharge features and streambeds, delivering runoff-related contaminants to Barton Springs.

The source, discharge, and chemical characteristics of water from Agua Caliente Spring, Palm Springs, California

USGS Publications Warehouse

Brandt, Justin; Catchings, Rufus D.; Christensen, Allen H.; Flint, Alan L.; Gandhok, Gini; Goldman, Mark R.; Halford, Keith J.; Langenheim, V.E.; Martin, Peter; Rymer, Michael J.; Schroeder, Roy A.; Smith, Gregory A.; Sneed, Michelle; Martin, Peter

2011-01-01

Agua Caliente Spring, in downtown Palm Springs, California, has been used for recreation and medicinal therapy for hundreds of years and currently (2008) is the source of hot water for the Spa Resort owned by the Agua Caliente Band of the Cahuilla Indians. The Agua Caliente Spring is located about 1,500 feet east of the eastern front of the San Jacinto Mountains on the southeast-sloping alluvial plain of the Coachella Valley. The objectives of this study were to (1) define the geologic structure associated with the Agua Caliente Spring; (2) define the source(s), and possibly the age(s), of water discharged by the spring; (3) ascertain the seasonal and longer-term variability of the natural discharge, water temperature, and chemical characteristics of the spring water; (4) evaluate whether water-level declines in the regional aquifer will influence the temperature of the spring discharge; and, (5) estimate the quantity of spring water that leaks out of the water-collector tank at the spring orifice.

Methods to estimate annual mean spring discharge to the Snake River between Milner Dam and King Hill, Idaho

USGS Publications Warehouse

Kjelstrom, L.C.

1995-01-01

Many individual springs and groups of springs discharge water from volcanic rocks that form the north canyon wall of the Snake River between Milner Dam and King Hill. Previous estimates of annual mean discharge from these springs have been used to understand the hydrology of the eastern part of the Snake River Plain. Four methods that were used in previous studies or developed to estimate annual mean discharge since 1902 were (1) water-budget analysis of the Snake River; (2) correlation of water-budget estimates with discharge from 10 index springs; (3) determination of the combined discharge from individual springs or groups of springs by using annual discharge measurements of 8 springs, gaging-station records of 4 springs and 3 sites on the Malad River, and regression equations developed from 5 of the measured springs; and (4) a single regression equation that correlates gaging-station records of 2 springs with historical water-budget estimates. Comparisons made among the four methods of estimating annual mean spring discharges from 1951 to 1959 and 1963 to 1980 indicated that differences were about equivalent to a measurement error of 2 to 3 percent. The method that best demonstrates the response of annual mean spring discharge to changes in ground-water recharge and discharge is method 3, which combines the measurements and regression estimates of discharge from individual springs.

Spring operated accelerator and constant force spring mechanism therefor

NASA Technical Reports Server (NTRS)

Shillinger, G. L., Jr. (Inventor)

1977-01-01

A spring assembly consisting of an elongate piece of flat spring material formed into a spiral configuration and a free running spool in circumscribing relation to which this spring is disposed was developed. The spring has a distal end that is externally accessible so that when the distal end is drawn along a path, the spring unwinds against a restoring force present in the portion of the spring that resides in a transition region between a relatively straight condition on the path and a fully wound condition on the spool. When the distal end is released, the distal end is accelerated toward the spool by the force existing at the transition region which force is proportional to the cross-sectional area of the spring.

Yakima/Klickitat Fisheries Project Genetic Studies; Yakima/Klickitat Fisheries Project Monitoring and Evaluation Report 1 of 7, 2003-2004 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Busack, Craig A.; Frye, Alice; Kassler, Todd

2004-05-01

Genetic work for 2003, as in previous years, was quite diverse. In chapter 1 we report on the use of DNA microsatellite markers to sex spring chinook collected at Roza. We have learned through comparison of sex determinations at Roza and then at CESRF that sexing green fish on the basis of morphology is somewhat inaccurate, and accurate sexing of fish at Roza is needed to estimate sex ratios of fish on the spawning grounds. Using DNA microsatellite markers, sexing accuracy was high, but not perfect. In chapter 2 we report on new genetic risk concepts currently being developed andmore » their implications for the YKFP spring chinook program. The impact on domestication of gene flow between the natural and hatchery spawning components is now much better understood. It is now possible to compare the risk of different hatchery programs much more quantitatively in the past. Thus, we can now make good predictions of how much less domesticating the Yakima spring chinook supplementation effort is than other programs. In chapter 3 we present the initial results of morphological comparisons of adult (1) hatchery-origin Upper Yakima spring chinook, (2) natural-origin U. Yakima spring chinook, and (3) Naches spring chinook. Canonical variate analysis allowed both sexes of the three groups to be classified correctly with over accuracy. The differences are subtle, but hatchery-origin fish appear to be someone thinner than natural-origin fish. This is consistent with observations of hatchery vs wild morphology in coho. In chapter 4 we describe the ongoing work to refine the Domestication Research/Monitoring Plan. Work for last year included analysis of the impact of HC line precocious males spawning in the wild, development of a misting incubation system for off-site incubation of Naches eggs, and refinement of some aspects of experimental design. The misting incubation system has broad applicability outside the project. The most recent version of the domestication monitoring plan is included as an appendix. In chapter 5 we present a final report on computer simulations of factorial mating designs. Using three different schemes for combining breeding values of fish, we found that full factorial mating offers a substantial increase in effective size over single-pair mating. Although full factorial mating may be too difficult logistically, but a significant proportion of the full factorial mating advantage can be obtained by using 2 x 2 partial factorials. We have developed a method that allows us to determine the relative effective size advantage of mixed partial factorial designs. In chapter 6 we report on an analysis of stock origin of smolts collected at Chandler. The 702 Chinook salmon smolts collected at the Chandler trap in 2003 were screened at 12 microsatellite DNA loci. A new Yakima basin baseline, consisting of spring chinook from the upper Yakima, Naches, and American River populations and fall chinook from the Marion Drain and lower Yakima populations, was created for these same 12 loci. DNA template problems with the tissue collections from the Naches, and American River populations prompted the omission of four loci prior to analysis. The results indicated: 80% Naches spring, 13% American River spring, 7% upper Yakima spring, and less than 1% for the two fall populations combined. The estimated stock proportions in the 2003 Chandler collection differed substantially from those for the 2002 collection. The temporal pattern of sampling in both Chandler smolt collections was not proportional to the observed outmigration in each year, suggesting that both of these estimates should be regarded with caution. Strengthening of the baseline data set will be a high priority for future work with Chandler smolts.« less

Assessment of spring cranioplasty biomechanics in sagittal craniosynostosis patients.

PubMed

Borghi, Alessandro; Schievano, Silvia; Rodriguez Florez, Naiara; McNicholas, Roisin; Rodgers, Will; Ponniah, Allan; James, Greg; Hayward, Richard; Dunaway, David; Jeelani, N U Owase

2017-11-01

OBJECTIVE Scaphocephaly secondary to sagittal craniosynostosis has been treated in recent years with spring-assisted cranioplasty, an innovative approach that leverages the use of metallic spring distractors to reshape the patient skull. In this study, a population of patients who had undergone spring cranioplasty for the correction of scaphocephaly at the Great Ormond Street Hospital for Children was retrospectively analyzed to systematically assess spring biomechanical performance and kinematics in relation to spring model, patient age, and outcomes over time. METHODS Data from 60 patients (49 males, mean age at surgery 5.2 ± 0.9 months) who had received 2 springs for the treatment of isolated sagittal craniosynostosis were analyzed. The opening distance of the springs at the time of insertion and removal was retrieved from the surgical notes and, during the implantation period, from planar radiographs obtained at 1 day postoperatively and at the 3-week follow-up. The force exerted by the spring to the patient skull at each time point was derived after mechanical testing of each spring model-3 devices with the same geometry but different wire thicknesses. Changes in the cephalic index between preoperatively and the 3-week follow-up were recorded. RESULTS Stiffer springs were implanted in older patients (p < 0.05) to achieve the same opening on-table as in younger patients, but this entailed significantly different-higher-forces exerted on the skull when combinations of stiffer springs were used (p < 0.001). After initial force differences between spring models, however, the devices all plateaued. Indeed, regardless of patient age or spring model, after 10 days from insertion, all the devices were open. CONCLUSIONS Results in this study provide biomechanical insights into spring-assisted cranioplasty and could help to improve spring design and follow-up strategy in the future.

Spring plant phenology and false springs in the conterminous US during the 21st century

USGS Publications Warehouse

Allstadt, Andrew J.; Vavrus, Stephen J.; Heglund, Patricia J.; Pidgeon, Anna M.; Thogmartin, Wayne E.; Radeloff, Volker C.

2015-01-01

The onset of spring plant growth has shifted earlier in the year over the past several decades due to rising global temperatures. Earlier spring onset may cause phenological mismatches between the availability of plant resources and dependent animals, and potentially lead to more false springs, when subsequent freezing temperatures damage new plant growth. We used the extended spring indices to project changes in spring onset, defined by leaf out and by first bloom, and predicted false springs until 2100 in the conterminous United States (US) using statistically-downscaled climate projections from the Coupled Model Intercomparison Project 5 ensemble. Averaged over our study region, the median shift in spring onset was 23 days earlier in the Representative Concentration Pathway 8.5 scenario with particularly large shifts in the Western US and the Great Plains. Spatial variation in phenology was due to the influence of short-term temperature changes around the time of spring onset versus season long accumulation of warm temperatures. False spring risk increased in the Great Plains and portions of the Midwest, but remained constant or decreased elsewhere. We conclude that global climate change may have complex and spatially variable effects on spring onset and false springs, making local predictions of change difficult.

Seismic hazard study for selected sites in New Mexico and Nevada

NASA Astrophysics Data System (ADS)

Johnston, J. C.

1983-12-01

Seismic hazard evaluations were conducted for specific sites in New Mexico and Nevada. For New Mexico, a model of seismicity was developed from historical accounts of medium to large shocks and the current microactivity record from local networks. Ninety percent confidence levels at Albuquerque and Roswell were computed to be 56 gals for a 10-year period and 77 gals for a 20-year period. Values of ground motion for Clovis were below these values. Peak velocity and displacement were also computed for each site. Deterministic spectra based on the estimated maximum credible earthquake for the zones which the sites occupy were also computed. For the sites in Nevada, the regionalizations used in Battis (1982) for the uniform seismicity model were slightly modified. For 10- and 20-year time periods, peak acceleration values for Indian Springs were computed to be 94 gals and 123 gals and for Hawthorne 206 gals and 268 gals. Deterministic spectra were also computed. The input parameters were well determined for the analysis for the Nevada sites because of the abundance of data. The values computed for New Mexico, however, are likely upper limits. As more data are collected from the area of the Rio Grande rift zone, the pattern of seismicity will become better understood. At this time a more detailed, and thus more accurate, model may emerge.

Modulation of the relationship between spring AO and the subsequent winter ENSO by the preceding November AO.

PubMed

Chen, Shangfeng; Chen, Wen; Yu, Bin

2018-05-02

Previous studies indicated that the spring Arctic Oscillation (AO) exerts significant influences on the subsequent winter El Niño-Southern Oscillation (ENSO). This analysis suggests that the spring AO-ENSO linkage is highly modulated by its preceding November AO. When November and the subsequent spring AO indices are in phase, the spring AO has a pronounced influence on ENSO. However, when the November and spring AO indices are out of phase, the spring AO-ENSO connection disappears. Modulation of the November AO on the spring AO-ENSO connection is mainly through the constructive and destructive superposition of the November and spring AO associated sea surface temperature (SST) anomalies in the tropical central-eastern Pacific in spring and summer, as well as the SST anomalies developed further in the tropical Pacific via the positive air-sea feedback.

Process for Forming a High Temperature Single Crystal Canted Spring

NASA Technical Reports Server (NTRS)

DeMange, Jeffrey J (Inventor); Ritzert, Frank J (Inventor); Nathal, Michael V (Inventor); Dunlap, Patrick H (Inventor); Steinetz, Bruce M (Inventor)

2017-01-01

A process for forming a high temperature single crystal canted spring is provided. In one embodiment, the process includes fabricating configurations of a rapid prototype spring to fabricate a sacrificial mold pattern to create a ceramic mold and casting a canted coiled spring to form at least one canted coil spring configuration based on the ceramic mold. The high temperature single crystal canted spring is formed from a nickel-based alloy containing rhenium using the at least one coil spring configuration.

Hydrogeochemical characteristics and sources of salinity of the springs near Wenquanzhen in the eastern Sichuan Basin, China

NASA Astrophysics Data System (ADS)

Guo, Juan; Zhou, Xun; Wang, Lidong; Zhang, Yuqi; Shen, Xiaowei; Zhou, Haiyan; Ye, Shen; Fang, Bin

2018-06-01

Natural springs have the potential to provide important information on hydrogeochemical processes within aquifers. This study used traditional and classic technical methods and procedures to determine the characteristics and evolution of springs to gain further knowledge on the differences between hot saline springs and cold fresh springs. In a short river segment near Wenquanzhen in the eastern Sichuan Basin, southwest China, several natural springs coexist with total dissolved solids (TDS) ranging from less than 1 to 15 g/L and temperatures from 15 to 40 °C. The springs emanate from the outcropping Lower and Middle Triassic carbonates in the river valley cutting the core of an anticline. The cold springs are of Cl·HCO3-Na·Ca and Cl·SO4-Na types, and the hot saline springs are mainly of Cl-Na type. The chemistry of the springs has undergone some changes with time. The stable hydrogen and oxygen isotopes indicate that the spring waters are of a meteoric origin. The salinity of the springs originates from dissolution of minerals, including halite, gypsum, calcite and dolomite. The evolution of the springs involves the following mechanisms: the groundwater receives recharge from infiltration of precipitation, then undergoes deep circulation in the core of the anticline (incongruent dissolution of the salt-bearing strata occurs), and emerges in the river valley in the form of hot springs with high TDS. Groundwater also undergoes shallow circulation in the northern and southern flanks of the anticline and appears in the river valley in the form of cold springs with low TDS.

Hydrogeochemical characteristics and sources of salinity of the springs near Wenquanzhen in the eastern Sichuan Basin, China

NASA Astrophysics Data System (ADS)

Guo, Juan; Zhou, Xun; Wang, Lidong; Zhang, Yuqi; Shen, Xiaowei; Zhou, Haiyan; Ye, Shen; Fang, Bin

2017-12-01

Natural springs have the potential to provide important information on hydrogeochemical processes within aquifers. This study used traditional and classic technical methods and procedures to determine the characteristics and evolution of springs to gain further knowledge on the differences between hot saline springs and cold fresh springs. In a short river segment near Wenquanzhen in the eastern Sichuan Basin, southwest China, several natural springs coexist with total dissolved solids (TDS) ranging from less than 1 to 15 g/L and temperatures from 15 to 40 °C. The springs emanate from the outcropping Lower and Middle Triassic carbonates in the river valley cutting the core of an anticline. The cold springs are of Cl·HCO3-Na·Ca and Cl·SO4-Na types, and the hot saline springs are mainly of Cl-Na type. The chemistry of the springs has undergone some changes with time. The stable hydrogen and oxygen isotopes indicate that the spring waters are of a meteoric origin. The salinity of the springs originates from dissolution of minerals, including halite, gypsum, calcite and dolomite. The evolution of the springs involves the following mechanisms: the groundwater receives recharge from infiltration of precipitation, then undergoes deep circulation in the core of the anticline (incongruent dissolution of the salt-bearing strata occurs), and emerges in the river valley in the form of hot springs with high TDS. Groundwater also undergoes shallow circulation in the northern and southern flanks of the anticline and appears in the river valley in the form of cold springs with low TDS.

Ground Contact Modeling for the Morpheus Test Vehicle Simulation

NASA Technical Reports Server (NTRS)

Cordova, Luis

2014-01-01

The Morpheus vertical test vehicle is an autonomous robotic lander being developed at Johnson Space Center (JSC) to test hazard detection technology. Because the initial ground contact simulation model was not very realistic, it was decided to improve the model without making it too computationally expensive. The first development cycle added capability to define vehicle attachment points (AP) and to keep track of their states in the lander reference frame (LFRAME). These states are used with a spring damper model to compute an AP contact force. The lateral force is then overwritten, if necessary, by the Coulomb static or kinetic friction force. The second development cycle added capability to use the PolySurface class as the contact surface. The class can load CAD data in STL (Stereo Lithography) format, and use the data to compute line of sight (LOS) intercepts. A polygon frame (PFRAME) is computed from the facet intercept normal and used to convert the AP state to PFRAME. Three flat plane tests validate the transitions from kinetic to static, static to kinetic, and vertical impact. The hazardous terrain test will be used to test for visual reasonableness. The improved model is numerically inexpensive, robust, and produces results that are reasonable.

Ground Contact Modeling for the Morpheus Test Vehicle Simulation

NASA Technical Reports Server (NTRS)

Cordova, Luis

2013-01-01

The Morpheus vertical test vehicle is an autonomous robotic lander being developed at Johnson Space Center (JSC) to test hazard detection technology. Because the initial ground contact simulation model was not very realistic, it was decided to improve the model without making it too computationally expensive. The first development cycle added capability to define vehicle attachment points (AP) and to keep track of their states in the lander reference frame (LFRAME). These states are used with a spring damper model to compute an AP contact force. The lateral force is then overwritten, if necessary, by the Coulomb static or kinetic friction force. The second development cycle added capability to use the PolySurface class as the contact surface. The class can load CAD data in STL (Stereo Lithography) format, and use the data to compute line of sight (LOS) intercepts. A polygon frame (PFRAME) is computed from the facet intercept normal and used to convert the AP state to PFRAME. Three flat plane tests validate the transitions from kinetic to static, static to kinetic, and vertical impact. The hazardous terrain test will be used to test for visual reasonableness. The improved model is numerically inexpensive, robust, and produces results that are reasonable.

Computational knee ligament modeling using experimentally determined zero-load lengths.

PubMed

Bloemker, Katherine H; Guess, Trent M; Maletsky, Lorin; Dodd, Kevin

2012-01-01

This study presents a subject-specific method of determining the zero-load lengths of the cruciate and collateral ligaments in computational knee modeling. Three cadaver knees were tested in a dynamic knee simulator. The cadaver knees also underwent manual envelope of motion testing to find their passive range of motion in order to determine the zero-load lengths for each ligament bundle. Computational multibody knee models were created for each knee and model kinematics were compared to experimental kinematics for a simulated walk cycle. One-dimensional non-linear spring damper elements were used to represent cruciate and collateral ligament bundles in the knee models. This study found that knee kinematics were highly sensitive to altering of the zero-load length. The results also suggest optimal methods for defining each of the ligament bundle zero-load lengths, regardless of the subject. These results verify the importance of the zero-load length when modeling the knee joint and verify that manual envelope of motion measurements can be used to determine the passive range of motion of the knee joint. It is also believed that the method described here for determining zero-load length can be used for in vitro or in vivo subject-specific computational models.

Patient attitudes toward using computers to improve health services delivery.

PubMed

Sciamanna, Christopher N; Diaz, Joseph; Myne, Puja

2002-09-11

The aim of this study was to examine the acceptability of point of care computerized prompts to improve health services delivery among a sample of primary care patients. Primary data collection. Cross-sectional survey. Patients were surveyed after their visit with a primary care provider. Data were obtained from patients of ten community-based primary care practices in the spring of 2001. Almost all patients reported that they would support using a computer before each visit to prompt their doctor to: "do health screening tests" (92%), "counsel about health behaviors (like diet and exercise)" (92%) and "change treatments for health conditions" (86%). In multivariate testing, the only variable that was associated with acceptability of the point of care computerized prompts was patient's confidence in their ability to answer questions about their health using a computer (beta = 0.39, p =.001). Concerns about data security were expressed by 36.3% of subjects, but were not related to acceptability of the prompts. Support for using computers to generate point of care prompts to improve quality-oriented processes of care was high in our sample, but may be contingent on patients feeling familiar with their personal medical history.

1. NORTHWEST FRONT, SOUTHWEST SIDE (SPRING HOUSE IN FOREGROUND; BATH ...

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

1. NORTHWEST FRONT, SOUTHWEST SIDE (SPRING HOUSE IN FOREGROUND; BATH HOUSE AT REAR) (4 x 5 negative; 5 x 7 print) - Salt Sulphur Springs, Spring House, U.S. Route 219, Salt Sulphur Springs, Monroe County, WV

"I just wanted to get away": An analysis of spring breakers' travel motivations

Treesearch

Nuno F. Ribeiro; Paul E. Durrenberger; Careen M. Yarnal; Garry E. Chick

2010-01-01

Scholarly research on Spring Break has grown substantially and has often associated spring breakers' motivations with a number of risky behaviors. Recent research, however, has challenged these assumptions. The purpose of this study was to examine spring breakers' motivations for going on Spring Break. Unlike the media portrayal of Spring Break as a time of...

Springs of Florida

USGS Publications Warehouse

Rosenau, Jack C.; Faulkner, Glen L.; Hendry, Charles W.; Hull, Robert W.

1977-01-01

The first comprehensive report of Florida's springs, which contains both a story of the springs and a collection of facts about them, was published thirty years ago (Ferguson and others, 1947). Since then, much additional data on springs have been gathered and the current report, Springs of Florida, makes a wealth of information on springs available to the public. Springs of Florida, prepared by the U.S. Geological Survey in cooperation with the Bureau of Geology, Florida Department of Natural Resources, publishers, and the Bureau of Water Resources Management, Florida Department of Environmental Regulation, is intended to provide sufficient background information for a lucid understanding of the nature and occurrence of the springs in the State.

Analytical solution and numerical study on water hammer in a pipeline closed with an elastically attached valve

NASA Astrophysics Data System (ADS)

Henclik, Sławomir

2018-03-01

The influence of dynamic fluid-structure interaction (FSI) onto the course of water hammer (WH) can be significant in non-rigid pipeline systems. The essence of this effect is the dynamic transfer of liquid energy to the pipeline structure and back, which is important for elastic structures and can be negligible for rigid ones. In the paper a special model of such behavior is analyzed. A straight pipeline with a steady flow, fixed to the floor with several rigid supports is assumed. The transient is generated by a quickly closed valve installed at the end of the pipeline. FSI effects are assumed to be present mainly at the valve which is fixed with a spring dash-pot attachment. Analysis of WH runs, especially transient pressure changes, for various stiffness and damping parameters of the spring dash-pot valve attachment is presented in the paper. The solutions are found analytically and numerically. Numerical results have been computed with the use of an own computer program developed on the basis of the four equation model of WH-FSI and the specific boundary conditions formulated at the valve. Analytical solutions have been found with the separation of variables method for slightly simplified assumptions. Damping at the dash-pot is taken into account within the numerical study. The influence of valve attachment parameters onto the WH courses was discovered and it was found the transient amplitudes can be reduced. Such a system, elastically attached shut-off valve in a pipeline or other, equivalent design can be a real solution applicable in practice.

Armored spring-core superconducting cable and method of construction

DOEpatents

McIntyre, Peter M.; Soika, Rainer H.

2002-01-01

An armored spring-core superconducting cable (12) is provided. The armored spring-core superconducting cable (12) may include a spring-core (20), at least one superconducting strand (24) wound onto the spring-core (20), and an armored shell (22) that encases the superconducting strands (24). The spring-core (20) is generally a perforated tube that allows purge gases and cryogenic liquids to be circulated through the armored superconducting cable (12), as well as managing the internal stresses within the armored spring-core superconducting cable (12). The armored shell (22) manages the external stresses of the armored spring-core superconducting cable (12) to protect the fragile superconducting strands (24). The armored spring-core superconducting cable (12) may also include a conductive jacket (34) formed outwardly of the armored shell (22).

Determination of groundwater travel time in a karst aquifer by stable water isotopes, Tanour and Rasoun spring (Jordan)

NASA Astrophysics Data System (ADS)

Hamdan, Ibraheem; Wiegand, Bettina; Sauter, Martin; Ptak, Thomas

2016-04-01

Key words: karst aquifers, stable isotopes, water travel time, Jordan. Tanour and Rasoun karst springs are located about 75 kilometers northwest of the city of Amman in Jordan. The aquifer is composed of Upper Cretaceous limestone that exhibits a moderate to high degree of karstification. The two springs represent the main drinking water resources for the surrounding villages. The yearly water production is about 1,135,000 m3/yr for Tanour spring and 125,350 m3/yr for Rasoun spring (MWI 2015). Due to contamination from microbiological pollution (leakage of wastewater from septic tanks) or infiltration of wastewater from local olive presses, drinking water supply from the two springs is frequently interrupted. From November 2014 through March 2015, spring water samples were collected from Tanour and Rasoun spring for the analysis of stable hydrogen and oxygen isotopes to investigate spring response to precipitation and snowmelt events. Both Tanour and Rasoun spring show a fast response to precipitation and snowmelt events, implying short water travel times. Based on the variation of δ 18O and δ 2H in spring discharge, the average maximum water travel time is in the order of 8 days for Tanour spring and 6 days for Rasoun spring. Due to fast water travel times, Tanour and Rasoun spring can be considered as highly vulnerable to pollutants. δ 18O and δ 2H values of Tanour and Rasoun springs parallel other monitored parameter like water temperature, turbidity, electrical conductivity and spring discharge. In addition, a high turbidity peak was monitored in Tanour spring during a pollution event from olive mills wastewater (Hamdan et al., 2016; Hamdan, in prep.). The fast response in both Tanour and Rasoun springs to precipitation events requires monitoring potential sources of pollution within the catchment area. References: MWI (Ministry of Water and Irrigation) (2015) Monthly Production values for Tanour and Rasoun Springs for the time period between 1996 and 2014. Water Information System, National Master Plan Directorate. Jordan. Hamdan I., Wiegand B., Toll M., Sauter M. (2016) Spring response to precipitation events using δ 18O and δ 2H in the Tanour catchment, NW-Jordan. Isotopes in Environmental and Health Studies journal. Accepted GIEH-2015-0139. Hamdan, I.~in preparation.~Characterization of groundwater flow and vulnerability assessment of karstic aquifer - A case study from Tanour and Rasoun spring catchment (Ajloun, NW-Jordan).~Ph.D. Thesis, University of Göttingen, Germany.

Correction of craniosynostosis using modified spring-assisted surgery.

PubMed

Shen, Weimin; Cui, Jie; Chen, Jianbin; Zou, Jijun; Ji, Yi; Chen, Haini; Xiongzheng, Mu

2015-03-01

The use of springs in craniofacial surgery was originated at Sahlgrenska University Hospital in 1997 as a way of remodeling the cranial vault postoperatively. After a decade of development, spring technology has been improved to a greater extent. However, there still exist some problems, such as the poor consistency of steel wire stretches, the wrong position of steel wire, the problem of increasing the elasticity of springs, and so on. We have designed a spring device for external uses. This device is composed of 3 parts. The first part is the outside of the spring ring. This ring is the same as the internal spring, only a little bigger. The second part is a small U-shaped hook, which is made of titanium plates and linked to the skull portion. The U-shaped hook is approximately 1 cm long and 1 cm wide. The hang is approximately 1 cm long and 0.6 cm wide. The U-shaped level length is 1 cm, but the level width should be equal to or bigger than the thickness of the skull. The third part is a steel wire, which is placed at 1 end of hook. We first conduct a strip craniotomy, then put 2 hooks at the bone ends and, after that, fix hooks on the skull. Finally, we pull the steel wire of the hook end out of the scalp, connect it with the external spring, and draw out the external spring. We performed 24 craniofacial spring placement procedures for 12 patients with craniosynostosis. We used 6 springs for 3 patients who had anterior plagiocephaly, 12 springs for 6 patients who had scaphocephaly, and 3 springs for another patient who had metopic synostosis and holoprosencephaly. We also used 3 springs for 2 patients who had metopic synostosis. The 12 patients have not required further surgeries so far, and there were no major complications. Spring dislodgement had not caused any complication in early cases. We could easily change the position of the spring rings from outside the scalp, regularly correct the elasticity of the spring rings, and replace spring rings to increase the traction. The head shapes of the 12 children have been improved significantly to use external spring rings. This therapeutic modality in craniofacial surgery has allowed minimization of the extent of surgery without compromising clinical outcomes. The authors have shown that the use of external spring techniques is safe and, in selected situations, offer significant advantages over other methods of treatment. It makes up for a number of shortcomings of internal springs.

Three-dimensional deformation response of a NiTi shape memory helical-coil actuator during thermomechanical cycling: experimentally validated numerical model

NASA Astrophysics Data System (ADS)

Dhakal, B.; Nicholson, D. E.; Saleeb, A. F.; Padula, S. A., II; Vaidyanathan, R.

2016-09-01

Shape memory alloy (SMA) actuators often operate under a complex state of stress for an extended number of thermomechanical cycles in many aerospace and engineering applications. Hence, it becomes important to account for multi-axial stress states and deformation characteristics (which evolve with thermomechanical cycling) when calibrating any SMA model for implementation in large-scale simulation of actuators. To this end, the present work is focused on the experimental validation of an SMA model calibrated for the transient and cyclic evolutionary behavior of shape memory Ni49.9Ti50.1, for the actuation of axially loaded helical-coil springs. The approach requires both experimental and computational aspects to appropriately assess the thermomechanical response of these multi-dimensional structures. As such, an instrumented and controlled experimental setup was assembled to obtain temperature, torque, degree of twist and extension, while controlling end constraints during heating and cooling of an SMA spring under a constant externally applied axial load. The computational component assesses the capabilities of a general, multi-axial, SMA material-modeling framework, calibrated for Ni49.9Ti50.1 with regard to its usefulness in the simulation of SMA helical-coil spring actuators. Axial extension, being the primary response, was examined on an axially-loaded spring with multiple active coils. Two different conditions of end boundary constraint were investigated in both the numerical simulations as well as the validation experiments: Case (1) where the loading end is restrained against twist (and the resulting torque measured as the secondary response) and Case (2) where the loading end is free to twist (and the degree of twist measured as the secondary response). The present study focuses on the transient and evolutionary response associated with the initial isothermal loading and the subsequent thermal cycles under applied constant axial load. The experimental results for the helical-coil actuator under two different boundary conditions are found to be within error to their counterparts in the numerical simulations. The numerical simulation and the experimental validation demonstrate similar transient and evolutionary behavior in the deformation response under the complex, inhomogeneous, multi-axial stress-state and large deformations of the helical-coil actuator. This response, although substantially different in magnitude, exhibited similar evolutionary characteristics to the simple, uniaxial, homogeneous, stress-state of the isobaric tensile tests results used for the model calibration. There was no significant difference in the axial displacement (primary response) magnitudes observed between Cases (1) and (2) for the number of cycles investigated here. The simulated secondary responses of the two cases evolved in a similar manner when compared to the experimental validation of the respective cases.

The ground-water system and possible effects of underground coal mining in the Trail Mountain area, central Utah

USGS Publications Warehouse

Lines, Gregory C.

1985-01-01

The ground-water system was studied in the Trail Mountain area in order to provide hydrologic information needed to assess the hydrologic effects of underground coal mining. Well testing and spring data indicate that water occurs in several aquifers. The coal-bearing Blackhawk-Star Point aquifer is regional in nature and is the source of most water in underground mines in the region. One or more perched aquifers overlie the Blackhawk-Star Point aquifer in most areas of Trail Mountain.Aquifer tests indicate that the transmissivity of the Blackhawk-Star Point aquifer, which consists mainly of sandstone, siltstone, and shale, ranges from about 20 to 200 feet squared per day in most areas of Trail Mountain. The specific yield of the aquifer was estimated at 0.05, and the storage coefficient is about IxlO"6 per foot of aquifer where confined.The main sources of recharge to the multiaquifer system are snowmelt and rain, and water is discharged mainly by springs and by leakage along streams. Springs that issue from perched aquifers are sources of water for livestock and wildlife on Trail Mountain.Water in all aquifers is suitable for most uses. Dissolved solids concentrations range from about 250 to 700 milligrams per liter, and the predominant dissolved constituents generally are calcium, magnesium, and bicarbonate. Future underground coal mines will require dewatering when they penetrate the Blackhawk-Star Point aquifer. A finitedifference, three-dimensional computer model was used to estimate the inflow of water to various lengths and widths of a hypothetical dewatered mine and to estimate drawdowns of potentiometric surfaces in the partly dewatered aquifer. The estimates were made for a range of aquifer properties and premining hydraulic gradients that were similar to those on Trail Mountain. The computer simulations indicate that mine inflows could be several hundred gallons per minute and that potentiometric surfaces of the partly dewatered aquifer could be drawn down by several hundred feet during a reasonable life span of a mine. Because the Blackhawk-Star Point aquifer is separated from overlying perched aquifers by an unsaturated zone, mine dewatering alone would not affect perched aquifers. Mine dewatering would not significantly change water quality in the Blackhawk-Star Point aquifer. Subsidence will occur above future underground mines, but the effects on the ground-water system cannot be quantified. Subsidence fractures possibly could extend from the roof of a mine into a perched aquifer several hundred feet above. Such fractures would increase down ward percolation of water through the perching bed, and spring discharge from the perched aquifer could decrease. Flow through subsidence fractures also could increase recharge to the Blackhawk-Star Point aquifer and increase inflows to underground mines.

Parametric studies of stitching effectiveness for preventing substructure disbond

NASA Technical Reports Server (NTRS)

Flanagan, Gerry; Furrow, Keith

1995-01-01

A methodology is desired that will allow a designer to select appropriate amounts of through-thickness reinforcement needed to meet design requirements. The goal is to use a relatively simple analysis to minimize the amount of testing that needs to be performed, and to make test results from simple configurations applicable to more general structures. Using this methodology one should be able to optimize the selection of stitching materials, the weight of the yarn, and the stitching density. The analysis approach is to treat substructure disbond as a crack propagation problem. In this approach, the stitches have little influence until a delamination begins to grow. Once the delamination reaches, or extends beyond a stitch, the stitch serves to reduce the strain-energy-release-rate (G) at the crack tip for a given applied load. The reduced G can then be compared to the unstitched materials toughness to predict the load required to further extend the crack. The current model treats the stitch as a simple spring which responds to displacements in the vertical (through-thickness) direction. In concept, this approach is similar to that proposed by other authors. Test results indicate that the model should be refined to include the shearing stiffness of the stitch. The strain-energy-release-rate calculations are performed using a code which uses interconnected higher-order plates to model built-up composite cross-sections. When plates are stacked vertically, the interfacial tractions between the plates can be computed. The plate differential equations are solved in closed-form. The code, called SUBLAM, was developed as part of this section in one dimension. Because of this limitation, rows of stitches are treated as a two-dimensional sheet. The spring stiffness of a row of stitches can be estimated from the stitch material, weight, and density. As a practical and conservative approach, we can assume that the stitch is bonded until a crack passes the stitch location. After the crack passes, it is fully bonded. A series of tests were performed to exercise this methodology and incorporated an attached flange such that the sudden change in thickness initiated a delamination. The analysis was used to estimate the materials' critical G from that of the unstitched specimens. With this data, a prediction was made for the load required to delaminate the stitched specimens. Using the methodology, design charts have been created for simplified geometries. These charts give stitch force, along with G(sub 1) and G(sub 2) as as function of the stitch spring stiffness. Using the charts, it should be possible to determine the stitch spring stiffness and strength required to reduce the G to a desired level. From these parameters, the actual stitching material, weight, and density can be computed.

Geochemical characterization of groundwater discharging from springs north of the Grand Canyon, Arizona, 2009–2016

USGS Publications Warehouse

Beisner, Kimberly R.; Tillman, Fred D.; Anderson, Jessica R.; Antweiler, Ronald C.; Bills, Donald J.

2017-08-01

A geochemical study was conducted on 37 springs discharging from the Toroweap Formation, Coconino Sandstone, Hermit Formation, Supai Group, and Redwall Limestone north of the Grand Canyon near areas of breccia-pipe uranium mining. Baseline concentrations were established for the elements As, B, Li, Se, SiO2, Sr, Tl, U, and V. Three springs exceeded U.S. Environmental Protection Agency drinking water standards: Fence Spring for arsenic, Pigeon Spring for selenium and uranium, and Willow (Hack) Spring for selenium. The majority of the spring sites had uranium values of less than 10 micrograms per liter (μg/L), but six springs discharging from all of the geologic units studied that are located stratigraphically above the Redwall Limestone had uranium values greater than 10 μg/L (Cottonwood [Tuckup], Grama, Pigeon, Rock, and Willow [Hack and Snake Gulch] Springs). The geochemical characteristics of these six springs with elevated uranium include Ca-Mg-SO4 water type, circumneutral pH, high specific conductance, correlation and multivariate associations between U, Mo, Sr, Se, Li, and Zn, low 87Sr/86Sr, low 234U/238U activity ratios (1.34–2.31), detectable tritium, and carbon isotopic interpretation indicating they may be a mixture of modern and pre-modern waters. Similar geochemical compositions of spring waters having elevated uranium concentrations are observed at sites located both near and away from sites of uranium-mining activities in the present study. Therefore, mining does not appear to explain the presence of elevated uranium concentrations in groundwater at the six springs noted above. The elevated uranium at the six previously mentioned springs may be influenced by iron mineralization associated with mineralized breccia pipe deposits. Six springs discharging from the Coconino Sandstone (Upper Jumpup, Little, Horse, and Slide Springs) and Redwall Limestone (Kanab and Side Canyon Springs) contained water with corrected radiocarbon ages as much as 9,300 years old. Of the springs discharging water with radiocarbon age, Kanab and Side Canyon Springs contain tritium of more than 1.3 picocuries per liter (pCi/L), indicating they may contain a component of modern water recharged after 1952. Springs containing high values of tritium (greater than 5.1 pCi/L), which may suggest a significant component of modern water, include Willow (Hack), Saddle Horse, Cottonwood (Tuckup), Hotel, Bitter, Unknown, Hole in the Wall, and Hanging Springs. Fence and Rider Springs, located on the eastern end of the study area near the Colorado River, have distinctly different geochemical compositions compared to the other springs of the study. Additionally, water from Fence Spring has the highest 87Sr/86Sr for samples analyzed from this study with a value greater than those known in sedimentary rocks from the region. Strontium isotope data likely indicate that water discharging at Fence Spring has interacted with Precambrian basement rocks. Rider Spring had the most depleted values of stable O and H isotopes indicating that recharge, if recent, occurred at higher elevations or was recharged during earlier, cooler-climate conditions.

Student Use of Physics to Make Sense of Incomplete but Functional VPython Programs in a Lab Setting

NASA Astrophysics Data System (ADS)

Weatherford, Shawn A.

2011-12-01

Computational activities in Matter & Interactions, an introductory calculus-based physics course, have the instructional goal of providing students with the experience of applying the same set of a small number of fundamental principles to model a wide range of physical systems. However there are significant instructional challenges for students to build computer programs under limited time constraints, especially for students who are unfamiliar with programming languages and concepts. Prior attempts at designing effective computational activities were successful at having students ultimately build working VPython programs under the tutelage of experienced teaching assistants in a studio lab setting. A pilot study revealed that students who completed these computational activities had significant difficultly repeating the exact same tasks and further, had difficulty predicting the animation that would be produced by the example program after interpreting the program code. This study explores the interpretation and prediction tasks as part of an instructional sequence where students are asked to read and comprehend a functional, but incomplete program. Rather than asking students to begin their computational tasks with modifying program code, we explicitly ask students to interpret an existing program that is missing key lines of code. The missing lines of code correspond to the algebraic form of fundamental physics principles or the calculation of forces which would exist between analogous physical objects in the natural world. Students are then asked to draw a prediction of what they would see in the simulation produced by the VPython program and ultimately run the program to evaluate the students' prediction. This study specifically looks at how the participants use physics while interpreting the program code and creating a whiteboard prediction. This study also examines how students evaluate their understanding of the program and modification goals at the beginning of the modification task. While working in groups over the course of a semester, study participants were recorded while they completed three activities using these incomplete programs. Analysis of the video data showed that study participants had little difficulty interpreting physics quantities, generating a prediction, or determining how to modify the incomplete program. Participants did not base their prediction solely from the information from the incomplete program. When participants tried to predict the motion of the objects in the simulation, many turned to their knowledge of how the system would evolve if it represented an analogous real-world physical system. For example, participants attributed the real-world behavior of springs to helix objects even though the program did not include calculations for the spring to exert a force when stretched. Participants rarely interpreted lines of code in the computational loop during the first computational activity, but this changed during latter computational activities with most participants using their physics knowledge to interpret the computational loop. Computational activities in the Matter & Interactions curriculum were revised in light of these findings to include an instructional sequence of tasks to build a comprehension of the example program. The modified activities also ask students to create an additional whiteboard prediction for the time-evolution of the real-world phenomena which the example program will eventually model. This thesis shows how comprehension tasks identified by Palinscar and Brown (1984) as effective in improving reading comprehension are also effective in helping students apply their physics knowledge to interpret a computer program which attempts to model a real-world phenomena and identify errors in their understanding of the use, or omission, of fundamental physics principles in a computational model.

Analysis of methods to estimate spring flows in a karst aquifer

USGS Publications Warehouse

Sepulveda, N.

2009-01-01

Hydraulically and statistically based methods were analyzed to identify the most reliable method to predict spring flows in a karst aquifer. Measured water levels at nearby observation wells, measured spring pool altitudes, and the distance between observation wells and the spring pool were the parameters used to match measured spring flows. Measured spring flows at six Upper Floridan aquifer springs in central Florida were used to assess the reliability of these methods to predict spring flows. Hydraulically based methods involved the application of the Theis, Hantush-Jacob, and Darcy-Weisbach equations, whereas the statistically based methods were the multiple linear regressions and the technology of artificial neural networks (ANNs). Root mean square errors between measured and predicted spring flows using the Darcy-Weisbach method ranged between 5% and 15% of the measured flows, lower than the 7% to 27% range for the Theis or Hantush-Jacob methods. Flows at all springs were estimated to be turbulent based on the Reynolds number derived from the Darcy-Weisbach equation for conduit flow. The multiple linear regression and the Darcy-Weisbach methods had similar spring flow prediction capabilities. The ANNs provided the lowest residuals between measured and predicted spring flows, ranging from 1.6% to 5.3% of the measured flows. The model prediction efficiency criteria also indicated that the ANNs were the most accurate method predicting spring flows in a karst aquifer. ?? 2008 National Ground Water Association.

Analysis of methods to estimate spring flows in a karst aquifer.

PubMed

Sepúlveda, Nicasio

2009-01-01

Hydraulically and statistically based methods were analyzed to identify the most reliable method to predict spring flows in a karst aquifer. Measured water levels at nearby observation wells, measured spring pool altitudes, and the distance between observation wells and the spring pool were the parameters used to match measured spring flows. Measured spring flows at six Upper Floridan aquifer springs in central Florida were used to assess the reliability of these methods to predict spring flows. Hydraulically based methods involved the application of the Theis, Hantush-Jacob, and Darcy-Weisbach equations, whereas the statistically based methods were the multiple linear regressions and the technology of artificial neural networks (ANNs). Root mean square errors between measured and predicted spring flows using the Darcy-Weisbach method ranged between 5% and 15% of the measured flows, lower than the 7% to 27% range for the Theis or Hantush-Jacob methods. Flows at all springs were estimated to be turbulent based on the Reynolds number derived from the Darcy-Weisbach equation for conduit flow. The multiple linear regression and the Darcy-Weisbach methods had similar spring flow prediction capabilities. The ANNs provided the lowest residuals between measured and predicted spring flows, ranging from 1.6% to 5.3% of the measured flows. The model prediction efficiency criteria also indicated that the ANNs were the most accurate method predicting spring flows in a karst aquifer.

49 CFR 236.822 - Switch, spring.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Switch, spring. 236.822 Section 236.822... Switch, spring. A switch equipped with a spring device which forces the points to their original position after being trailed through and holds them under spring compression. ...

49 CFR 236.822 - Switch, spring.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Switch, spring. 236.822 Section 236.822... Switch, spring. A switch equipped with a spring device which forces the points to their original position after being trailed through and holds them under spring compression. ...

49 CFR 236.822 - Switch, spring.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Switch, spring. 236.822 Section 236.822... Switch, spring. A switch equipped with a spring device which forces the points to their original position after being trailed through and holds them under spring compression. ...

49 CFR 236.822 - Switch, spring.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Switch, spring. 236.822 Section 236.822... Switch, spring. A switch equipped with a spring device which forces the points to their original position after being trailed through and holds them under spring compression. ...

49 CFR 236.822 - Switch, spring.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Switch, spring. 236.822 Section 236.822... Switch, spring. A switch equipped with a spring device which forces the points to their original position after being trailed through and holds them under spring compression. ...

Influence of Locally Derived Recharge on the Water Quality and Temperature of Springs in Hot Springs National Park, Arkansas

USGS Publications Warehouse

Bell, Richard W.; Hays, Phillip D.

2007-01-01

The hot springs of Hot Springs National Park consist of a mixture of water from two recharge components: a primary hot-water component and a secondary cold-water component. Widespread distribution of fractures enables mixing of the hot- and cold-water components of flow near the discharge area for the springs. Urbanization in the area near the hot springs of Hot Springs National Park has increased the potential for degradation of the quality of surface-water runoff and locally derived ground-water recharge to the hot springs. Previous studies by the U.S. Geological Survey have indicated that water from some cold-water springs and wells in the vicinity of Hot Springs, Arkansas, showed evidence of contamination and that water from locally derived cold-water recharge might contribute 25 percent of the total flow to the hot springs after storms. Water samples were collected during base-flow conditions at nine hot springs and two cold-water springs in September 2000. Nine hot springs and one cold-water spring were resampled in October 2001 after a storm that resulted in a measurable decrease in water temperature in selected hot springs. Water samples were analyzed for a variety of dissolved chemical constituents (nutrients, major ions, trace elements, pesticides, semivolatile compounds, isotopes, and radiochemicals), physical properties, field measurements, and bacteria. Comparison of analyses of samples collected during base-flow conditions from the springs in 2000 and during a storm event in 2001 with the results from earlier studies dating back to the late 1800's indicates that little change in major, minor, and trace constituent chemistry has occurred and that the water continues to be of excellent quality. Water-quality data show distinguishable differences in water chemistry of the springs during base-flow and stormflow conditions, indicating changing input of cold-water recharge relative to hot-water recharge. Silica, total dissolved solids, strontium, barium, and sulfate show statistically significant differences between the median values of base-flow and stormflow samples. While variations in these constituents do not degrade water quality, the differences do provide evidence of variability in the factors controlling water quality of the hot springs and show that water quality is influenced by the locally derived, cold-water component of flow to the springs. Water temperature was measured continuously (3-minute intervals) between August 2000 and October 2002 at four hot springs. Continuous water-temperature data at the springs provide no indication of persistent long-term change in water temperature through time. Short time-scale water-temperature decreases occur in response to mixing of hot-springs water with locally derived recharge after storm events; the magnitude of these decreases varied inversely with the amount of rainfall. Maximum decreases in water temperature for specific storms had a non-linear relation with the amount of precipitation measured for the events. Response time for water temperature to begin decreasing from baseline temperature as a result of storm recharge was highly variable. Some springs began decreasing from baseline temperature as quickly as 1 hour after the beginning of a storm; one spring had an 8-hour minimum response time to show a storm-related temperature decrease. Water-quality, water-temperature, isotopic, and radiochemical data provide multiple lines of evidence supporting the importance of the contribution of cold-water recharge to hot springs. All the springs sampled indicated some measure of influence from local recharge. Binary mixing models using silica and total dissolved solids indicate that cold-water recharge from stormflow contributes an estimated 10 to 31 percent of the flow of hot springs. Models using water temperature indicate that cold-water recharge from stormflow contributes an estimated 1 to 35 percent of the flow of the various hot springs. Alth

Recharge Area, Base-Flow and Quick-Flow Discharge Rates and Ages, and General Water Quality of Big Spring in Carter County, Missouri, 2000-04

USGS Publications Warehouse

Imes, Jeffrey L.; Plummer, Niel; Kleeschulte, Michael J.; Schumacher, John G.

2007-01-01

Exploration for lead deposits has occurred in a mature karst area of southeast Missouri that is highly valued for its scenic beauty and recreational opportunities. The area contains the two largest springs in Missouri (Big Spring and Greer Spring), both of which flow into federally designated scenic rivers. Concerns about potential mining effects on the area ground water and aquatic biota prompted an investigation of Big Spring. Water-level measurements made during 2000 helped define the recharge area of Big Spring, Greer Spring, Mammoth Spring, and Boze Mill Spring. The data infer two distinct potentiometric surfaces. The shallow potentiometric surface, where the depth-to-water is less than about 250 feet, tends to mimic topographic features and is strongly controlled by streams. The deep potentiometric surface, where the depth-to-water is greater than about 250 feet represents ground-water hydraulic heads within the more mature karst areas. A highly permeable zone extends about 20 mile west of Big Spring toward the upper Hurricane Creek Basin. Deeper flowing water in the Big Spring recharge area is directed toward this permeable zone. The estimated sizes of the spring recharge areas are 426 square miles for Big Spring, 352 square miles for Greer Spring, 290 square miles for Mammoth Spring, and 54 square miles for Boze Mill Spring. A discharge accumulation curve using Big Spring daily mean discharge data shows no substantial change in the discharge pattern of Big Spring during the period of record (water years 1922 through 2004). The extended periods when the spring flow deviated from the trend line can be attributed to prolonged departures from normal precipitation. The maximum possible instantaneous flow from Big Spring has not been adequately defined because of backwater effects from the Current River during high-flow conditions. Physical constraints within the spring conduit system may restrict its maximum flow. The largest discharge measured at Big Spring during the period of record (water years 1922 through 2004) was 1,170 cubic feet per second on December 7, 1982. The daily mean water temperature of Big Spring was monitored during water years 2001 through 2004 and showed little variability, ranging from 13 to 15? C (degree Celsius). Water temperatures generally vary less than 1? C throughout the year. The warmest temperatures occur during October and November and decrease until April, indicating Big Spring water temperature does show a slight seasonal variation. The use of the traditional hydrograph separation program HYSEP to determine the base flow and quick flow or runoff components at Big Spring failed to yield base-flow and quick-flow discharge curves that matched observations of spring characteristics. Big Spring discharge data were used in combination with specific conductance data to develop an improved hydrograph separation method for the spring. The estimated annual mean quick flow ranged from 15 to 48 cubic feet per second for the HYSEP analysis and ranged from 26 to 154 cubic feet per second for the discharge and specific conductance method for water years 2001 to 2004. Using the discharge and specific conductance method, the estimated base-flow component rises abruptly as the spring hydrograph rises, attains a peak value on the same day as the discharge peak, and then declines abruptly from its peak value. Several days later, base flow begins to increase again at an approximately linear trend, coinciding with the time at which the percentage of quick flow has reached a maximum after each recharge-induced discharge peak. The interval between the discharge peak and the peak in percentage quick flow ranges from 8 to 11 days for seven hydrograph peaks, consistent with quick-flow traveltime estimates by dye-trace tests from the mature karst Hurricane Creek Basin in the central part of the recharge area. Concentrations of environmental tracers chlorofluorocarbons (CFCs: CFC-11, CFC-12, CFC-113)

Springs as Ecosystems: Clarifying Groundwater Dependence and Wetland Status (Invited)

NASA Astrophysics Data System (ADS)

Stevens, L.; Springer, A. E.; Ledbetter, J. D.

2013-12-01

Springs ecosystems are among the most productive, biologically diverse and culturally important ecosystems on Earth. Net annual productivity of some springs exceeds 5 kg/m^2/yr. Springs support an estimated 19% of the endangered species and numerous rare taxa in the United States. Springs serve as keystone ecosystems in arid regions, and as cornerstones of indigenous cultural well-being, history, economics, and aesthetics. Despite their significance, the ecosystem ecology and stewardship of springs have received scant scientific and public attention, resulting in loss or impairment of 50-90% of the springs in many regions, both arid and temperate. Six reasons contribute to the lack of attention to springs. Springs are poorly mapped because: 1) their generally small size is less than the pixel area of most remote sensing analyses and they are overlooked; and 2) springs detection is often limited by emergence on cliff faces, beneath heavy vegetation cover, or under water. In addition, 3) high levels of ecosystem complexity at springs require multidisciplinary team approaches for inventory, assessment, and research, but collaboration between the fields of hydrogeology and ecology has been limited. 4) Protectionism by land owners and organizations that manage springs limits the availability information, preventing regional assessment of status. 5) Prior to recent efforts, the absence of a descriptive lexicon of springs types has limited discussion about variation in ecological characteristics and processes. 6) Neither regarded entirely as groundwater or as surface water, springs fall 'between jurisdictional cracks' and are not subject to clear legal and regulatory oversight. With regards to the latter point, two jurisdictional phrases have reduced scientific understanding and stewardship of springs ecosystems: 'jurisdictional wetlands' and 'groundwater-dependent ecosystems' (GDEs). Most springs have insufficient monitoring data to establish perenniality or the range of natural variation in flow, and many of the 12 springs types do not develop hydric soils or wetland vegetation. These factors and their normally small size preclude springs as jurisdictional wetlands by U.S. Environmental Protection Agency and Army Corps of Engineers criteria. Helocrenes (springfed wet meadows, cienegas, and some fens) are considered as wetlands, but the other 11 types of terrestrial springs often are not. The use of the phrase 'GDE' applies to any aquatic ecosystem supported by groundwater, and the utility of this phrase as a descriptor of springs is diluted by its application to all subterranean and surface aquatic habitats. The failure to recognize the importance of springs ecosystems has become a quiet but global crisis, in part due to inappropriate conceptual understanding and poor jurisdictional terminology. We clarify relationships between these concepts and terms to establish effective, consistent monitoring, assessment, restoration, management, and monitoring goals and protocols for improving springs stewardship.

Nonthermal springs of Utah

USGS Publications Warehouse

Mundorff, J.C.

1971-01-01

Data are presented for about 4,500 nonthermal springs that discharge in the State of Utah. Most major springs having discharge of several cubic feet per second or more are in or near mountain ranges or plateaus where precipitation is much greater than in other parts of the State. The largest instantaneous discharge observed at any spring was 314 cfs at Mammoth Spring in southwestern Utah.  Discharges exceeding 200 cfs have been observed at Swan Creek Spring in extreme northern Utah, and discharges of 200 cfs have been reported for Big Brush Creek Spring in northeastern Utah. Maximum discharges generally are during or within a few weeks after the main period of snowmelt, which is usually from late April to the middle of June.The largest springs generally discharge form or very near carbonate rocks in which solution channels and fractures are numerous or from areas of porous or fractured volcanic rocks. Most nonthermal springs in Utah probably are variable springs – that is, their variability of discharge exceeds 100 percent.Most of the major springs discharge water that contains less than 500 ppm (parts per million) of dissolved solids, and most of the water is of the calcium bicarbonate type. Water from springs is used for domestic, municipal, irrigation, livestock, mining, and industrial purposes.

Bacterial and archaeal diversities in Yunnan and Tibetan hot springs, China.

PubMed

Song, Zhao-Qi; Wang, Feng-Ping; Zhi, Xiao-Yang; Chen, Jin-Quan; Zhou, En-Min; Liang, Feng; Xiao, Xiang; Tang, Shu-Kun; Jiang, Hong-Chen; Zhang, Chuanlun L; Dong, Hailiang; Li, Wen-Jun

2013-04-01

Thousands of hot springs are located in the north-eastern part of the Yunnan-Tibet geothermal zone, which is one of the most active geothermal areas in the world. However, a comprehensive and detailed understanding of microbial diversity in these hot springs is still lacking. In this study, bacterial and archaeal diversities were investigated in 16 hot springs (pH 3.2-8.6; temperature 47-96°C) in Yunnan Province and Tibet, China by using a barcoded 16S rRNA gene-pyrosequencing approach. Aquificae, Proteobacteria, Firmicutes, Deinococcus-Thermus and Bacteroidetes comprised the large portion of the bacterial communities in acidic hot springs. Non-acidic hot springs harboured more and variable bacterial phyla than acidic springs. Desulfurococcales and unclassified Crenarchaeota were the dominated groups in archaeal populations from most of the non-acidic hot springs; whereas, the archaeal community structure in acidic hot springs was simpler and characterized by Sulfolobales and Thermoplasmata. The phylogenetic analyses showed that Aquificae and Crenarchaeota were predominant in the investigated springs and possessed many phylogenetic lineages that have never been detected in other hot springs in the world. Thus findings from this study significantly improve our understanding of microbial diversity in terrestrial hot springs. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

Structural analysis of compression helical spring used in suspension system

NASA Astrophysics Data System (ADS)

Jain, Akshat; Misra, Sheelam; Jindal, Arun; Lakhian, Prateek

2017-07-01

The main aim of this work has to develop a helical spring for shock absorber used in suspension system which is designed to reduce shock impulse and liberate kinetic energy. In a vehicle, it increases comfort by decreasing amplitude of disturbances and it improves ride quality by absorbing and dissipating energy. When a vehicle is in motion on a road and strikes a bump, spring comes into action quickly. After compression, spring will attempt to come to its equilibrium state which is on level road. Helical springs can be made lighter with more strength by reducing number of coils and increasing the area. In this research work, a helical spring is modeled and analyzed to substitute the existing steel spring which is used in suspension. By using different materials, stress and deflection of helical spring can be varied. Comparability between existing spring and newly replaced spring is used to verify the results. For finding detailed stress distribution, finite element analysis is used to find stresses and deflection in both the helical springs. Finite element analysis is a method which is used to find proximate solutions of a physical problem defined in a finite domain. In this research work, modeling of spring is accomplished using Solid Works and analysis on Ansys.

Hydrology and Water Quality near Bromide Pavilion in Chickasaw National Recreation Area, Murray County, Oklahoma, 2000

USGS Publications Warehouse

Andrews, William J.; Burrough, Steven P.

2002-01-01

The Bromide Pavilion in Chickasaw National Recreation Area drew many thousands of people annually to drink the mineral-rich waters piped from nearby Bromide and Medicine Springs. Periodic detection of fecal coliform bacteria in water piped to the pavilion from the springs, low yields of the springs, or flooding by adjacent Rock Creek prompted National Park Service officials to discontinue piping of the springs to the pavilion in the 1970s. Park officials would like to resume piping mineralized spring water to the pavilion to restore it as a visitor attraction, but they are concerned about the ability of the springs to provide sufficient quantities of potable water. Pumping and sampling of Bromide and Medicine Springs and Rock Creek six times during 2000 indicate that these springs may not provide sufficient water for Bromide Pavilion to supply large numbers of visitors. A potential problem with piping water from Medicine Spring is the presence of an undercut, overhanging cliff composed of conglomerate, which may collapse. Evidence of intermittent inundation of the springs by Rock Creek and seepage of surface water into the spring vaults from the adjoining creek pose a threat of contamination of the springs. Escherichia coli, fecal coliform, and fecal streptococcal bacteria were detected in some samples from the springs, indicating possible fecal contamination. Cysts of Giardia lamblia and oocysts of Cryptosporidium parvum protozoa were not detected in the creek or the springs. Total culturable enteric viruses were detected in only one water sample taken from Rock Creek.

49 CFR 230.111 - Spring rigging.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Spring rigging. 230.111 Section 230.111... Tenders Trucks, Frames and Equalizing System § 230.111 Spring rigging. (a) Arrangement of springs and equalizers. Springs and equalizers shall be arranged to ensure the proper distribution of weight to the...

49 CFR 230.111 - Spring rigging.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Spring rigging. 230.111 Section 230.111... Tenders Trucks, Frames and Equalizing System § 230.111 Spring rigging. (a) Arrangement of springs and equalizers. Springs and equalizers shall be arranged to ensure the proper distribution of weight to the...

49 CFR 230.111 - Spring rigging.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Spring rigging. 230.111 Section 230.111... Tenders Trucks, Frames and Equalizing System § 230.111 Spring rigging. (a) Arrangement of springs and equalizers. Springs and equalizers shall be arranged to ensure the proper distribution of weight to the...

49 CFR 230.111 - Spring rigging.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Spring rigging. 230.111 Section 230.111... Tenders Trucks, Frames and Equalizing System § 230.111 Spring rigging. (a) Arrangement of springs and equalizers. Springs and equalizers shall be arranged to ensure the proper distribution of weight to the...

76 FR 46288 - Adequacy Determination for Colorado Springs, Cañon City, Greeley, Pagosa Springs, and Telluride...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-02

... Springs, Ca[ntilde]on City, Greeley, Pagosa Springs, and Telluride; Carbon Monoxide and PM 10 Maintenance... transportation conformity purposes: ``Revised Carbon Monoxide Attainment/Maintenance Plan Colorado Springs Attainment/ Maintenance Area'' and ``Revised Carbon Monoxide Maintenance Plan Greeley Attainment/Maintenance...

49 CFR 230.109 - Tender trucks.

Code of Federal Regulations, 2012 CFR

2012-10-01

... bolsters. Truck bolsters shall be maintained approximately level. (c) Condemning defects for springs or spring rigging. Springs or spring rigging with any of the following defects shall be taken out of service immediately and renewed or properly repaired: (1) An elliptical spring with its top (long) leaf or any other...

49 CFR 230.109 - Tender trucks.

Code of Federal Regulations, 2013 CFR

2013-10-01

... bolsters. Truck bolsters shall be maintained approximately level. (c) Condemning defects for springs or spring rigging. Springs or spring rigging with any of the following defects shall be taken out of service immediately and renewed or properly repaired: (1) An elliptical spring with its top (long) leaf or any other...

77 FR 9840 - Amendment of Class E Airspace; Colorado Springs, CO

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-21

...-1191; Airspace Docket No. 11-ANM-21] Amendment of Class E Airspace; Colorado Springs, CO AGENCY... airspace at City of Colorado Springs Municipal Airport, Colorado Springs, CO. Decommissioning of the Black... controlled airspace at Colorado Springs, CO (76 FR 70920). Interested parties were invited to participate in...

49 CFR 230.109 - Tender trucks.

Code of Federal Regulations, 2011 CFR

2011-10-01

... bolsters. Truck bolsters shall be maintained approximately level. (c) Condemning defects for springs or spring rigging. Springs or spring rigging with any of the following defects shall be taken out of service immediately and renewed or properly repaired: (1) An elliptical spring with its top (long) leaf or any other...

49 CFR 230.109 - Tender trucks.

Code of Federal Regulations, 2014 CFR

2014-10-01

... bolsters. Truck bolsters shall be maintained approximately level. (c) Condemning defects for springs or spring rigging. Springs or spring rigging with any of the following defects shall be taken out of service immediately and renewed or properly repaired: (1) An elliptical spring with its top (long) leaf or any other...

Investigation of membrane mechanics using spring networks: application to red-blood-cell modelling.

PubMed

Chen, Mingzhu; Boyle, Fergal J

2014-10-01

In recent years a number of red-blood-cell (RBC) models have been proposed using spring networks to represent the RBC membrane. Some results predicted by these models agree well with experimental measurements. However, the suitability of these membrane models has been questioned. The RBC membrane, like a continuum membrane, is mechanically isotropic throughout its surface, but the mechanical properties of a spring network vary on the network surface and change with deformation. In this work spring-network mechanics are investigated in large deformation for the first time via an assessment of the effect of network parameters, i.e. network mesh, spring type and surface constraint. It is found that a spring network is conditionally equivalent to a continuum membrane. In addition, spring networks are employed for RBC modelling to replicate the optical tweezers test. It is found that a spring network is sufficient for modelling the RBC membrane but strain-hardening springs are required. Moreover, the deformation profile of a spring network is presented for the first time via the degree of shear. It is found that spring-network deformation approaches continuous as the mesh density increases. Copyright © 2014 Elsevier B.V. All rights reserved.

Hot springs of the central Sierra Nevada, California

USGS Publications Warehouse

Mariner, R.H.; Presser, T.S.; Evans, William C.

1977-01-01

Thermal springs of the central Sierra Nevada issue dilute to slightly saline sodium chloride, sodium bicarbonate, or sodium mixed-anion waters ranging in pH from 6.4 to 9.3. The solubility of chalcedony appears to control the silica concentration in most of the spring waters. Fales Hot Springs may be associated with a higher temperature aquifer, 150 degrees Celsius or more, in which quartz is controlling the silica concentration. Carbon dioxide is the predominant gas escaping from Fales Hot Springs, the unnamed hot spring on the south side of Mono Lake, and the two thermal springs near Bridgeport. Most of the other thermal springs issue small amounts of gas consisting principally of nitrogen. Methane is the major component of the gas escaping from the unnamed spring on Paoha Island in Mono Lake. The deuterium and oxygen isotopic composition of most of the thermal waters are those expected for local meteoric water which has undergone minor water-rock reaction. The only exceptions are the hot spring on Paoha Island in Mono Lake and perhaps the unnamed warm spring (south side of Mono Lake) which issues mixtures of thermal water and saline lake water. (Woodard-USGS)

Spring-Mediated Cranioplasty in Sagittal Synostosis: Does Age at Placement Affect Expansion?

PubMed

Sun, James; Ter Maaten, Netanja S; Mazzaferro, Daniel M; Wes, Ari M; Naran, Sanjay; Bartlett, Scott P; Taylor, Jesse A

2018-05-01

The aim of this study is to evaluate the effect of timing of surgery and spring characteristics on correction of scaphocephalic deformity in patients undergoing spring-mediated cranioplasty (SMC) for sagittal craniosynostosis. The authors conducted a review of patients with sagittal craniosynostosis who underwent SMC at a tertiary referral center between July 2011 and March 2017, with a primary outcome measure of head shape, both preoperatively and postoperatively, determined by cephalic index (CI). Patient demographics and operative details including timing of surgery and spring characteristics were collected. Differences in CI preoperation and postoperation were compared using Wilcoxon signed-rank test. Ordinary least-squares linear regression was used to assess the impact of timing, number of springs, maximum single spring force, and total spring force on postoperative change in CI. Thirty-six subjects (12 males and 24 females) were included in the study. Mean age at spring placement was 3.9 months (range: 1.9-9.2) with a mean follow-up of 1.4 years (range: 0.3-5.2). The mean number of springs used was 3 (range: 2-4). The mean maximum single spring force was 9.9 Newtons (N) (range: 6.9-13.0) and the mean total spring force was 24.6 N (range: 12.7-37.0). Mean CI increased from 70 ± 0.9 preoperatively to 77 ± 1.0 postoperatively (P < 0.001). Age at spring placement was significantly associated with change in CI: for every month increase in age, the change in CI decreased by 1.3 (P = 0.03). The number of springs used, greatest single spring force, and total spring force did not correlate with changes in CI (P = 0.85, P = 0.42, and P = 0.84, respectively). In SMC, earlier age at time of surgery appears to correlate with greater improvement in CI, at least in the short-term. While spring characteristics did not appear to affect head shape, it is possible that the authors were underpowered to detect a difference, and spring-related variables likely deserve additional study.

Interannual variability of the frontal activity in the Southern Hemisphere: relationship with atmospheric circulation and precipitation over southern South America

NASA Astrophysics Data System (ADS)

Blázquez, Josefina; Solman, Silvina A.

2017-04-01

The interannual variability of the frontal activity over the western Southern Hemisphere and its linkage with the variability of the atmospheric circulation and precipitation over southern South America is studied. The analysis is focused on the austral winter and spring seasons. The frontal activity is represented by an index defined as the product between the horizontal gradient of temperature and the relative vorticity at 850 hPa (FI) and is computed from the ERA Interim and NCEP2 reanalysis. For the two seasons the main mode of variability of FI, as depicted by the first Empirical Orthogonal Function, presents centres of action located in the southern part of the western Southern Hemisphere. This pattern is present in the two reanalysis datasets. The correlation coefficients between the principal component of the leading mode of FI and the two main modes of the 500 hPa geopotential height indicate that both the ENSO-mode and the SAM modulate the leading pattern of FI in winter while during the spring season the ENSO-mode controls the FI variability. The variability of the FI has a robust influence on the interannual variability of precipitation over southern South America and adjacent oceans. Over the continent, it was found that the pattern of precipitation anomalies associated with the variability of the FI depicts significant signals over southeastern South America (SESA), centre and south of Chile for winter and over SESA and southeastern Brazil for spring and agrees with the pattern of the leading mode of precipitation variability over southern South America.

Experimental AMO physics in undergraduate optics and lasers courses

NASA Astrophysics Data System (ADS)

Hoyt, Chad

2017-04-01

This talk will describe experimental AMO research projects in undergraduate Lasers and Optics courses at Bethel University. The courses, which include a comprehensive lecture portion, are built on open-ended projects that have a novel aspect. Classes begin with four weeks of small student groups rotating between several standard laser and optics laboratory exercises. These may include, for example, alignment and characterization of a helium neon laser and measurements with a Michelson interferometer or a scanning Fabry-Pérot optical cavity. During the following seven weeks of the course, student groups (2-4 people) choose and pursue research questions in the lab. Their work culminates in a group manuscript and a twenty-minute presentation to the class. Projects in the spring, 2016 Optics course included experiments with ultracold lithium atoms in a magneto-optical trap, a prototype, portable, mode-locked erbium fiber laser, a home-built fiber laser frequency comb, double-slit imaging with single photons, and digital holographic tweezers (led by Nathan Lindquist). Projects in the spring, 2015 Lasers course included ultrafast optics with a mode-locked erbium fiber laser, quantum optics, surface plasmon lasers (led by Nathan Lindquist) and a low-cost, near-infrared spectrometer. Several of these projects are related to larger scale, funded research in the physics department. The format and experience in Lasers and Optics is representative of other upper-level courses at Bethel, including Fluid Mechanics and Computer Methods. A physics education research group from the University of Colorado evaluated the spring, 2015 Lasers and 2016 Optics courses. They focused on student experimental attitudes and measurements of student project ownership.

Remote sensing of chlorophyll in the Baltic Sea at basin scale from 1997 to 2012 using merged multi-sensor data

NASA Astrophysics Data System (ADS)

Pitarch, Jaime; Volpe, Gianluca; Colella, Simone; Krasemann, Hajo; Santoleri, Rosalia

2016-03-01

A 15-year (1997-2012) time series of chlorophyll a (Chl a) in the Baltic Sea, based on merged multi-sensor satellite data was analysed. Several available Chl a algorithms were sea-truthed against the largest in situ publicly available Chl a data set ever used for calibration and validation over the Baltic region. To account for the known biogeochemical heterogeneity of the Baltic, matchups were calculated for three separate areas: (1) the Skagerrak and Kattegat, (2) the central Baltic, including the Baltic Proper and the gulfs of Riga and Finland, and (3) the Gulf of Bothnia. Similarly, within the operational context of the Copernicus Marine Environment Monitoring Service (CMEMS) the three areas were also considered as a whole in the analysis. In general, statistics showed low linearity. However, a bootstrapping-like assessment did provide the means for removing the bias from the satellite observations, which were then used to compute basin average time series. Resulting climatologies confirmed that the three regions display completely different Chl a seasonal dynamics. The Gulf of Bothnia displays a single Chl a peak during spring, whereas in the Skagerrak and Kattegat the dynamics are less regular and composed of highs and lows during winter, progressing towards a small bloom in spring and a minimum in summer. In the central Baltic, Chl a follows a dynamics of a mild spring bloom followed by a much stronger bloom in summer. Surface temperature data are able to explain a variable fraction of the intensity of the summer bloom in the central Baltic.<

The origin of Korotkoff sounds and the accuracy of auscultatory blood pressure measurements.

PubMed

Babbs, Charles F

2015-12-01

This study explores the hypothesis that the sharper, high frequency Korotkoff sounds come from resonant motion of the arterial wall, which begins after the artery transitions from a buckled state to an expanding state. The motions of one mass, two nonlinear springs, and one damper, driven by transmural pressure under the cuff, are used to model and compute the Korotkoff sounds according to principles of classical Newtonian physics. The natural resonance of this spring-mass-damper system provides a concise, yet rigorous, explanation for the origin of Korotkoff sounds. Fundamentally, wall stretching in expansion requires more force than wall bending in buckling. At cuff pressures between systolic and diastolic arterial pressure, audible vibrations (> 40 Hz) occur during early expansion of the artery wall beyond its zero pressure radius after the outward moving mass of tissue experiences sudden deceleration, caused by the discontinuity in stiffness between bucked and expanded states. The idealized spring-mass-damper model faithfully reproduces the time-domain waveforms of actual Korotkoff sounds in humans. Appearance of arterial sounds occurs at or just above the level of systolic pressure. Disappearance of arterial sounds occurs at or just above the level of diastolic pressure. Muffling of the sounds is explained by increased resistance of the artery to collapse, caused by downstream venous engorgement. A simple analytical model can define the physical origin of Korotkoff sounds, suggesting improved mechanical or electronic filters for their selective detection and confirming the disappearance of the Korotkoff sounds as the optimal diastolic end point. Copyright © 2015 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

Estimation of natural historical flows for the Manitowish River near Manitowish Waters, Wisconsin

USGS Publications Warehouse

Juckem, Paul F.; Reneau, Paul C.; Robertson, Dale M.

2012-01-01

The Wisconsin Department of Natural Resources is charged with oversight of dam operations throughout Wisconsin and is considering modifications to the operating orders for the Rest Lake Dam in Vilas County, Wisconsin. State law requires that the operation orders be tied to natural low flows at the dam. Because the presence of the dam confounds measurement of natural flows, the U.S. Geological Survey, in cooperation with the Wisconsin Department of Natural Resources, installed streamflow-gaging stations and developed two statistical methods to improve estimates of natural flows at the Rest Lake Dam. Two independent methods were used to estimate daily natural flow for the Manitowish River approximately 1 mile downstream of the Rest Lake Dam. The first method was an adjusted drainage-area ratio method, which used a regression analysis that related measured water yield (flow divided by watershed area) from short-term (2009–11) gaging stations upstream of the Manitowish Chain of Lakes to the water yield from two nearby long-term gaging stations in order to extend the flow record (1991–2011). In this approach, the computed flows into the Chain of Lakes at the upstream gaging stations were multiplied by a coefficient to account for the monthly hydrologic contributions (precipitation, evaporation, groundwater, and runoff) associated with the additional watershed area between the upstream gaging stations and the dam at the outlet of the Chain of Lakes (Rest Lake Dam). The second method used to estimate daily natural flow at the Rest Lake Dam was a water-budget approach, which used lake stage and dam outflow data provided by the dam operator. A water-budget model was constructed and then calibrated with an automated parameter-estimation program by matching simulated flow-duration statistics with measured flow-duration statistics at the upstream gaging stations. After calibration of the water-budget model, the model was used to compute natural flow at the dam from 1973 to 2011. Daily natural flows at the dam, as computed by the adjusted drainage-area ratio method and the water-budget method, were used to compute monthly flow-duration values for the period of historical data available for each method. Monthly flow-durations provide a means for evaluating the frequency and range in flows that have been observed for each month over the course of many years. Both methods described the pattern and timing of measured high-flow and low-flow events at the upstream gaging stations. The adjusted drainage-area ratio method generally had smaller residual errors across the full range of observed flows and had smaller monthly biases than the water-budget method. Although it is not possible to evaluate which method may be more "correct" for estimating monthly natural flows at the dam, comparisons between the results of each method indicate that the adjusted drainage-area ratio method may be susceptible to biases at high flows due to isolated storms outside of the Manitowish River watershed. Conversely, it appears that the water-budget method may be susceptible to biases at low flows because of its sensitivity to the accuracy of reported lake stage and outflows, as well as effects of upstream diversions that could not be fully compensated for with this method. Results from both methods are useful for understanding the natural flow patterns at the dam. Flows for both methods have similar patterns, with high median flows in spring and low median flows in late summer. Similarly, the range from monthly high-flow durations to low-flow durations increases during spring, decreases during summer, and increases again during fall. These seasonal patterns illustrate a challenge with interpreting a single value of natural low flow. That is, a natural low flow computed for September is not representative of a natural low flow in April. Moreover, alteration of natural flows caused by storing water in the Chain of Lakes during spring and releasing it in fall causes a change in the timing of high and low flows compared with natural conditions. That is, the lowest reported dam outflows occurred in spring and highest reported outflows occurred in fall, which is opposite the natural patterns.

Plants as indicators of focused ground water discharge to a northern Minnesota lake

USGS Publications Warehouse

Rosenberry, D.O.; Striegl, Robert G.; Hudson, D.C.

2000-01-01

Determining the discharge of ground water to Shingobee Lake (66 ha), north-central Minnesota, is complicated by the presence of numerous springs situated adjacent to the lake and in the shallow portion of the lakebed. Springs first had to be located before these areas of more rapid discharge could be quantified. Two methods that rely on the distribution of aquatic plants are useful for locating springs. One method identifies areas of the near-shore lakebed where floating-leaf and emergent aquatic vegetation are absent. The second method uses the distribution of marsh marigold (Caltha palustris L.) to locate springs that discharge on land near the shoreline of the lake. Marsh marigold produces large (2 to 4 cm diameter) yellow flowers that provide a ready marker for locating ground water springs. Twice as many springs (38) were identified using this method as were identified using the lack of near-shore vegetation. A portable weir was used to measure discharge from onshore springs, and seepage meters were used to measure discharge from near-shore springs. Of the total 56.7 L s-1 that enters the lake from ground water, approximately 30% comes from onshore and near-shore springs.Determining the discharge of ground water to Shingobee Lake (66 ha), north-central Minnesota, is complicated by the presence of numerous springs situated adjacent to the lake and in the shallow portion of the lakebed. Springs first had to be located before these areas of more rapid discharge could be quantified. Two methods that rely on the distribution of aquatic plants are useful for locating springs. One method identifies areas of the near-shore lakebed where floating-leaf and emergent aquatic vegetation are absent. The second method uses the distribution of marsh marigold (Caltha palustris L.) to locate springs that discharge on land near the shoreline of the lake. Marsh marigold produces large (2 to 4 cm diameter) yellow flowers that provide a ready marker for locating ground water springs. Twice as many springs (38) were identified using this method as were identified using the lack of near-shore vegetation. A portable weir was used to measure discharge from onshore springs, and seepage meters were used to measure discharge from near-shore springs. Of the total 56.7 L s-1 that enters the lake from ground water, approximately 30% comes from onshore and near-shore springs.

Application of an airfoil stall flutter computer prediction program to a three-dimensional wing: Prediction versus experiment. M.S. Thesis

NASA Technical Reports Server (NTRS)

Muffoletto, A. J.

1982-01-01

An aerodynamic computer code, capable of predicting unsteady and C sub m values for an airfoil undergoing dynamic stall, is used to predict the amplitudes and frequencies of a wing undergoing torsional stall flutter. The code, developed at United Technologies Research Corporation (UTRC), is an empirical prediction method designed to yield unsteady values of normal force and moment, given the airfoil's static coefficient characteristics and the unsteady aerodynamic values, alpha, A and B. In this experiment, conducted in the PSU 4' x 5' subsonic wind tunnel, the wing's elastic axis, torsional spring constant and initial angle of attack are varied, and the oscillation amplitudes and frequencies of the wing, while undergoing torsional stall flutter, are recorded. These experimental values show only fair comparisons with the predicted responses. Predictions tend to be good at low velocities and rather poor at higher velocities.

Computational approach to seasonal changes of living leaves.

PubMed

Tang, Ying; Wu, Dong-Yan; Fan, Jing

2013-01-01

This paper proposes a computational approach to seasonal changes of living leaves by combining the geometric deformations and textural color changes. The geometric model of a leaf is generated by triangulating the scanned image of a leaf using an optimized mesh. The triangular mesh of the leaf is deformed by the improved mass-spring model, while the deformation is controlled by setting different mass values for the vertices on the leaf model. In order to adaptively control the deformation of different regions in the leaf, the mass values of vertices are set to be in proportion to the pixels' intensities of the corresponding user-specified grayscale mask map. The geometric deformations as well as the textural color changes of a leaf are used to simulate the seasonal changing process of leaves based on Markov chain model with different environmental parameters including temperature, humidness, and time. Experimental results show that the method successfully simulates the seasonal changes of leaves.

Understanding Lymphatic Valve Function via Computational Modeling

NASA Astrophysics Data System (ADS)

Wolf, Ki; Nepiyushchikh, Zhanna; Razavi, Mohammad; Dixon, Brandon; Alexeev, Alexander

2017-11-01

The lymphatic system is a crucial part to the circulatory system with many important functions, such as transport of interstitial fluid, fatty acid, and immune cells. Lymphatic vessels' contractile walls and valves allow lymph flow against adverse pressure gradients and prevent back flow. Yet, the effect of lymphatic valves' geometric and mechanical properties to pumping performance and lymphatic dysfunctions like lymphedema is not well understood. Our coupled fluid-solid computational model based on lattice Boltzmann model and lattice spring model investigates the dynamics and effectiveness of lymphatic valves in resistance minimization, backflow prevention, and viscoelastic response under different geometric and mechanical properties, suggesting the range of lymphatic valve parameters with effective pumping performance. Our model also provides more physiologically relevant relations of the valve response under varied conditions to a lumped parameter model of the lymphatic system giving an integrative insight into lymphatic system performance, including its failure due to diseases. NSF CMMI-1635133.

Project summaries

NASA Technical Reports Server (NTRS)

1990-01-01

Lunar base projects, including a reconfigurable lunar cargo launcher, a thermal and micrometeorite protection system, a versatile lifting machine with robotic capabilities, a cargo transport system, the design of a road construction system for a lunar base, and the design of a device for removing lunar dust from material surfaces, are discussed. The emphasis on the Gulf of Mexico project was on the development of a computer simulation model for predicting vessel station keeping requirements. An existing code, used in predicting station keeping requirements for oil drilling platforms operating in North Shore (Alaska) waters was used as a basis for the computer simulation. Modifications were made to the existing code. The input into the model consists of satellite altimeter readings and water velocity readings from buoys stationed in the Gulf of Mexico. The satellite data consists of altimeter readings (wave height) taken during the spring of 1989. The simulation model predicts water velocity and direction, and wind velocity.

Computational model of polarized actin cables and cytokinetic actin ring formation in budding yeast

PubMed Central

Tang, Haosu; Bidone, Tamara C.

2015-01-01

The budding yeast actin cables and contractile ring are important for polarized growth and division, revealing basic aspects of cytoskeletal function. To study these formin-nucleated structures, we built a 3D computational model with actin filaments represented as beads connected by springs. Polymerization by formins at the bud tip and bud neck, crosslinking, severing, and myosin pulling, are included. Parameter values were estimated from prior experiments. The model generates actin cable structures and dynamics similar to those of wild type and formin deletion mutant cells. Simulations with increased polymerization rate result in long, wavy cables. Simulated pulling by type V myosin stretches actin cables. Increasing the affinity of actin filaments for the bud neck together with reduced myosin V pulling promotes the formation of a bundle of antiparallel filaments at the bud neck, which we suggest as a model for the assembly of actin filaments to the contractile ring. PMID:26538307

The Shuttle Mission Simulator computer generated imagery

NASA Technical Reports Server (NTRS)

Henderson, T. H.

1984-01-01

Equipment available in the primary training facility for the Space Transportation System (STS) flight crews includes the Fixed Base Simulator, the Motion Base Simulator, the Spacelab Simulator, and the Guidance and Navigation Simulator. The Shuttle Mission Simulator (SMS) consists of the Fixed Base Simulator and the Motion Base Simulator. The SMS utilizes four visual Computer Generated Image (CGI) systems. The Motion Base Simulator has a forward crew station with six-degrees of freedom motion simulation. Operation of the Spacelab Simulator is planned for the spring of 1983. The Guidance and Navigation Simulator went into operation in 1982. Aspects of orbital visual simulation are discussed, taking into account the earth scene, payload simulation, the generation and display of 1079 stars, the simulation of sun glare, and Reaction Control System jet firing plumes. Attention is also given to landing site visual simulation, and night launch and landing simulation.

High-performance parallel analysis of coupled problems for aircraft propulsion

NASA Technical Reports Server (NTRS)

Felippa, C. A.; Farhat, C.; Lanteri, S.; Maman, N.; Piperno, S.; Gumaste, U.

1994-01-01

This research program deals with the application of high-performance computing methods for the analysis of complete jet engines. We have entitled this program by applying the two dimensional parallel aeroelastic codes to the interior gas flow problem of a bypass jet engine. The fluid mesh generation, domain decomposition, and solution capabilities were successfully tested. We then focused attention on methodology for the partitioned analysis of the interaction of the gas flow with a flexible structure and with the fluid mesh motion that results from these structural displacements. This is treated by a new arbitrary Lagrangian-Eulerian (ALE) technique that models the fluid mesh motion as that of a fictitious mass-spring network. New partitioned analysis procedures to treat this coupled three-component problem are developed. These procedures involved delayed corrections and subcycling. Preliminary results on the stability, accuracy, and MPP computational efficiency are reported.

State-space prediction of spring discharge in a karst catchment in southwest China

NASA Astrophysics Data System (ADS)

Li, Zhenwei; Xu, Xianli; Liu, Meixian; Li, Xuezhang; Zhang, Rongfei; Wang, Kelin; Xu, Chaohao

2017-06-01

Southwest China represents one of the largest continuous karst regions in the world. It is estimated that around 1.7 million people are heavily dependent on water derived from karst springs in southwest China. However, there is a limited amount of water supply in this region. Moreover, there is not enough information on temporal patterns of spring discharge in the area. In this context, it is essential to accurately predict spring discharge, as well as understand karst hydrological processes in a thorough manner, so that water shortages in this area could be predicted and managed efficiently. The objectives of this study were to determine the primary factors that govern spring discharge patterns and to develop a state-space model to predict spring discharge. Spring discharge, precipitation (PT), relative humidity (RD), water temperature (WD), and electrical conductivity (EC) were the variables analyzed in the present work, and they were monitored at two different locations (referred to as karst springs A and B, respectively, in this paper) in a karst catchment area in southwest China from May to November 2015. Results showed that a state-space model using any combinations of variables outperformed a classical linear regression, a back-propagation artificial neural network model, and a least square support vector machine in modeling spring discharge time series for karst spring A. The best state-space model was obtained by using PT and RD, which accounted for 99.9% of the total variation in spring discharge. This model was then applied to an independent data set obtained from karst spring B, and it provided accurate spring discharge estimates. Therefore, state-space modeling was a useful tool for predicting spring discharge in karst regions in southwest China, and this modeling procedure may help researchers to obtain accurate results in other karst regions.

Assessment of the geothermal potential of southwestern New Mexico. Final report, July 1, 1978-April 30, 1980

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elston, W.E.

1981-07-01

Results are reported of geologic mapping of geothermal anomalies in the Gila Hot Springs KGRA/Mimbres Hot Springs area, Grant County. They suggest that both hot-spring occurrences are structurally controlled by the intersection of a major Basin and Range fault and the disturbed margin of an ash-flow tuff cauldron. Hydrothermal alteration in both areas is related to mid-Tertiary volcanism, not to modern hot springs. At Gila Hot Springs, the geothermal aquifer is a zone at the contact between the unwelded top of a major ash-flow tuff sheet (Bloodgood Canyon Rhyolite Tuff) and a succession of interlayered vesicular basaltic andesite flows andmore » thin sandstone beds (Bearwallow Mountain Formation). Scattered groups of natural hot springs occur at intersections of this zone and the faults bordering the northeastern side of the Gila Hot Springs graben. Hydrothermal alteration of Bloodgood Canyon Rhyolite Tuff near major faults seems to have increased its permeability. At Mimbres Hot Springs, a single group of hot springs is controlled by the intersection of the Mimbres Hot Springs fault and a fractured welded ash-flow tuff that fills the Emory cauldron (Kneeling Nun Tuff). Gila Hot Springs and Mimbres Hot Springs do not seem to be connected by throughgoing faults. At both localities, hot spring water is used locally for space heating and domestic hot water; at Gila Hot Springs, water of 65.6/sup 0/C (150/sup 0/F) is used to generate electricity by means of a 10 kw freon Rankine Cycle engine. This is the first such application in New Mexico.« less

Relation between flow and temporal variations of nitrate and pesticides in two karst springs in northern Alabama

USGS Publications Warehouse

Kingsbury, J.A.

2008-01-01

Two karst springs in the Mississippian Carbonate Aquifer of northern Alabama were sampled between March 1999 and March 2001 to characterize the variability in concentration of nitrate, pesticides, selected pesticide degradates, water temperature, and inorganic constituents. Water temperature and inorganic ion data for McGeehee Spring indicate that this spring represents a shallow flow system with a relatively short average ground-water residence time. Water issuing from the larger of the two springs, Meridianville Spring, maintained a constant temperature, and inorganic ion data indicate that this water represents a deeper flow system having a longer average ground-water residence time than McGeehee Spring. Although water-quality data indicate differing short-term responses to rainfall at the two springs, the seasonal variation of nitrate and pesticide concentrations generally is similar for the two springs. With the exception of pesticides detected at low concentrations, the coefficient of variation for most constituent concentrations was less than that of flow at both springs, with greater variability in concentration at McGeehee Spring. Degradates of the herbicides atrazine and fluometuron were detected at concentrations comparable to or greater than the parent pesticides. Decreases in concentration of the principal degradate of fluometuron from about July to November indicate that the degradation rate may decrease as fluometuron (demethylfluometuron) moves deeper into the soil after application. Data collected during the study show that from about November to March when recharge rates increase, nitrate and residual pesticides in the soil, unsaturated zone, and storage within the aquifer are transported to the spring discharges. Because of the increase in recharge, fluometuron loads discharged from the springs during the winter were comparable to loads discharged at the springs during the growing season. ?? 2008 American Water Resources Association.

Big Data Processing for a Central Texas Groundwater Case Study

NASA Astrophysics Data System (ADS)

Cantu, A.; Rivera, O.; Martínez, A.; Lewis, D. H.; Gentle, J. N., Jr.; Fuentes, G.; Pierce, S. A.

2016-12-01

As computational methods improve, scientists are able to expand the level and scale of experimental simulation and testing that is completed for case studies. This study presents a comparative analysis of multiple models for the Barton Springs segment of the Edwards aquifer. Several numerical simulations using state-mandated MODFLOW models ran on Stampede, a High Performance Computing system housed at the Texas Advanced Computing Center, were performed for multiple scenario testing. One goal of this multidisciplinary project aims to visualize and compare the output data of the groundwater model using the statistical programming language R to find revealing data patterns produced by different pumping scenarios. Presenting data in a friendly post-processing format is covered in this paper. Visualization of the data and creating workflows applicable to the management of the data are tasks performed after data extraction. Resulting analyses provide an example of how supercomputing can be used to accelerate evaluation of scientific uncertainty and geological knowledge in relation to policy and management decisions. Understanding the aquifer behavior helps policy makers avoid negative impact on the endangered species, environmental services and aids in maximizing the aquifer yield.

Nurses and computers. An international perspective on nurses' requirements.

PubMed

Bond, Carol S

2007-01-01

This paper reports the findings from a Florence Nightingale Foundation Travel Scholarship undertaken by the author in the spring of 2006. The aim of the visit was to explore nurses' attitudes towards, and experiences of, using computers in their practice, and the requirements that they have to encourage, promote and support them in using ICT. Nurses were found to be using computers mainly for carrying out administrative tasks, such as updating records, rather than as information tools to support evidence based practice, or patient information needs. Nurses discussed the systems they used, the equipment provided, and their skills, or more often their lack of skills. The need for support was a frequent comment, most nurses feeling that it was essential that help was available at the point of need, and that it was provided by someone, preferably a nurse, who understood the work context. Three groups of nurses were identified. Engagers; Worried Willing and Resisters. The report concludes that pre-registration education has a responsibility to seek to ensure that newly qualified nurses enter practice as engagers.

Payload and General Support Computer (PGSC) Detailed Test Objective (DTO) number 795 postflight report: STS-41

NASA Technical Reports Server (NTRS)

Adolf, Jurine A.; Beberness, Benjamin J.; Holden, Kritina L.

1991-01-01

Since 1983, the Space Transportation System (STS) had routinely flown the GRiD 1139 (80286) laptop computer as a portable onboard computing resource. In the spring of 1988, the GRiD 1530, an 80386 based machine, was chosen to replace the GRiD 1139. Human factors ground evaluations and detailed test objectives (DTO) examined the usability of the available display types under different lighting conditions and various angle deviations. All proved unsuitable due to either flight qualification of usability problems. In 1990, an Electroluminescent (EL) display for the GRiD 1530 became flight qualified and another DTO was undertaken to examine this display on-orbit. Under conditions of indirect sunlight and low ambient light, the readability of the text and graphics was only limited by the observer's distance from the display. Although a problem of direct sunlight viewing still existed, there were no problems with large angular deviations nor dark adaptation. No further evaluations were deemed necessary. The GRiD 1530 with the EL display was accepted by the STS program as the new standard for the PGSC.

Dr. Phil's Art Corner: Searching and Cobra Canyon.

PubMed

2018-01-01

Philip Alexander, M.D., is a native Texan, retired physician, and accomplished musician and artist. After 41 years as an internal medicine physician, Dr. Phil retired from his practice in College Station in 2016. A lifelong musician and former music professor, he often performs as an oboe soloist for the Brazos Valley Symphony Orchestra. He began exploring visual art in 1980, evolving from pencil sketches-including an official White House portrait of President Ronald Reagan-to the computer-generated drawings featured in this journal. His images, which first appeared in this journal in the spring of 2012, are his own original creations.

Continuation of periodic orbits in symmetric Hamiltonian and conservative systems

NASA Astrophysics Data System (ADS)

Galan-Vioque, J.; Almaraz, F. J. M.; Macías, E. F.

2014-12-01

We present and review results on the continuation and bifurcation of periodic solutions in conservative, reversible and Hamiltonian systems in the presence of symmetries. In particular we show how two-point boundary value problem continuation software can be used to compute families of periodic solutions of symmetric Hamiltonian systems. The technique is introduced with a very simple model example (the mathematical pendulum), justified with a theoretical continuation result and then applied to two non trivial examples: the non integrable spring pendulum and the continuation of the figure eight solution of the three body problem.

Flexible Volumetric Structure

NASA Technical Reports Server (NTRS)

Cagle, Christopher M. (Inventor); Schlecht, Robin W. (Inventor)

2014-01-01

A flexible volumetric structure has a first spring that defines a three-dimensional volume and includes a serpentine structure elongatable and compressible along a length thereof. A second spring is coupled to at least one outboard edge region of the first spring. The second spring is a sheet-like structure capable of elongation along an in-plane dimension thereof. The second spring is oriented such that its in-plane dimension is aligned with the length of the first spring's serpentine structure.

Weight compensation characteristics of Armeo®Spring exoskeleton: implications for clinical practice and research.

PubMed

Perry, Bonnie E; Evans, Emily K; Stokic, Dobrivoje S

2017-02-17

Armeo®Spring exoskeleton is widely used for upper extremity rehabilitation; however, weight compensation provided by the device appears insufficiently characterized to fully utilize it in clinical and research settings. Weight compensation was quantified by measuring static force in the sagittal plane with a load cell attached to the elbow joint of Armeo®Spring. All upper spring settings were examined in 5° increments at the minimum, maximum, and two intermediate upper and lower module length settings, while keeping the lower spring at minimum. The same measurements were made for minimum upper spring setting and maximum lower spring setting at minimum and maximum module lengths. Weight compensation was plotted against upper module angles, and slope was analyzed for each condition. The Armeo®Spring design prompted defining the slack angle and exoskeleton balance angle, which, depending on spring and length settings, divide the operating range into different unloading and loading regions. Higher spring tensions and shorter module lengths provided greater unloading (≤6.32 kg of support). Weight compensation slope decreased faster with shorter length settings (minimum length = -0.082 ± 0.002 kg/°; maximum length = -0.046 ± 0.001 kg/°) independent of spring settings. Understanding the impact of different settings on the Armeo®Spring weight compensation should help define best clinical practice and improve fidelity of research.

78 FR 33991 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-06

... of Candle Harris County. Creek Road. Approximately 500 feet +125 upstream of Spring Cypress Road. K131-00-00 (Spring Gully) At the Cypress Creek +106 Unincorporated Areas of confluence. Harris County. Approximately 200 feet +137 downstream of Spring Cypress Road. K131-03-03 (Tributary 2.1 to Spring At the Spring...

78 FR 41227 - Endangered and Threatened Wildlife and Plants; Determination of Endangered Species Status for Six...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-09

... common in a very restricted range. system (four springs). Phantom Lake springsnail....... San Solomon Spring very rare in a very restricted range. system (four springs). diminutive amphipod San Solomon... Solomon Spring System. However, we use this term as a common reference for the four springs, which are...

77 FR 11796 - Proposed Amendment of Class E Airspace; Rock Springs, WY

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-28

...-0131; Airspace Docket No. 12-ANM-2 Proposed Amendment of Class E Airspace; Rock Springs, WY AGENCY... action proposes to amend Class E airspace at Rock Springs-Sweetwater County Airport, Rock Springs, WY. Decommissioning of the Rock Springs Tactical Air Navigation System (TACAN) has made this action necessary for the...

78 FR 37792 - Mario Julian Martinez-Bernache, Inmate Number #95749-279, CI Big Spring, Corrections Institution...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-24

... DEPARTMENT OF COMMERCE Bureau of Industry and Security Mario Julian Martinez-Bernache, Inmate Number 95749-279, CI Big Spring, Corrections Institution, 2001 Rickabaugh Drive, Big Spring, TX 79720... Spring, Corrections Institution, 2001 Rickabaugh Drive, Big Spring, TX 79720, and when acting for or on...

Studying Springs in Series Using a Single Spring

ERIC Educational Resources Information Center

Serna, Juan D.; Joshi, Amitabh

2011-01-01

Springs are used for a wide range of applications in physics and engineering. Possibly, one of their most common uses is to study the nature of restoring forces in oscillatory systems. While experiments that verify Hooke's law using springs are abundant in the physics literature, those that explore the combination of several springs together are…

78 FR 21260 - Safety Zone; Lubbers Cup Regatta; Spring Lake, MI

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-10

...-AA00 Safety Zone; Lubbers Cup Regatta; Spring Lake, MI AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on Spring Lake in Spring Lake, Michigan. This safety zone is intended to restrict vessels from a portion of Spring Lake due to...

Spring break trips as a risk factor for heavy alcohol use among first-year college students.

PubMed

Lee, Christine M; Maggs, Jennifer L; Rankin, Lela A

2006-11-01

Many high school and college students are believed to use spring break vacation to travel to destinations with the intent of engaging in extreme party behaviors, including excessive alcohol use. However, the extent to which spring break travelers' behaviors are more risky than their typical behaviors remains unclear. To assess the impact of spring break as a situational risk factor, we analyzed data collected from 176 first-year college students across 10 weeks using weekly telephone interviews. Using multilevel modeling, we found the following: (1) men, participants in fraternity/sorority organizations, students traveling on spring break trips, and those with higher fun-social alcohol expectancies drank more during the regular semester; (2) alcohol use did not increase during spring break week in general; however, (3) spring break travelers increased their alcohol use during spring break. Spring break trips are a risk factor for escalated alcohol use both during the academic semester and during spring break trips, suggesting that some students may seek out opportunities for excessive alcohol use. Results are discussed in terms of niche selection and prevention implications.

Base excitation testing system using spring elements to pivotally mount wind turbine blades

DOEpatents

Cotrell, Jason; Hughes, Scott; Butterfield, Sandy; Lambert, Scott

2013-12-10

A system (1100) for fatigue testing wind turbine blades (1102) through forced or resonant excitation of the base (1104) of a blade (1102). The system (1100) includes a test stand (1112) and a restoring spring assembly (1120) mounted on the test stand (1112). The restoring spring assembly (1120) includes a primary spring element (1124) that extends outward from the test stand (1112) to a blade mounting plate (1130) configured to receive a base (1104) of blade (1102). During fatigue testing, a supported base (1104) of a blad (1102) may be pivotally mounted to the test stand (1112) via the restoring spring assembly (1120). The system (1100) may include an excitation input assembly (1140) that is interconnected with the blade mouting plate (1130) to selectively apply flapwise, edgewise, and/or pitch excitation forces. The restoring spring assemply (1120) may include at least one tuning spring member (1127) positioned adjacent to the primary spring element (1124) used to tune the spring constant or stiffness of the primary spring element (1124) in one of the excitation directions.

Unexpected fungal communities in the Rehai thermal springs of Tengchong influenced by abiotic factors.

PubMed

Liu, Kai-Hui; Ding, Xiao-Wei; Salam, Nimaichand; Zhang, Bo; Tang, Xiao-Fei; Deng, Baiwan; Li, Wen-Jun

2018-05-01

Fungal communities represent an indispensable part of the geothermal spring ecosystem; however, studies on fungal community within hot springs are still scant. Here, we used Illumina HiSeq 2500 sequencing to detect fungal community diversity in extremely acidic hot springs (pH < 4) and neutral and alkaline springs (pH > 6) of Tengchong-indicated by the presence of over 0.75 million valid reads. These sequences were phylogenetically assigned to 5 fungal phyla, 67 order, and 375 genera, indicating unexpected fungal diversity in the hot springs. The genera such as Penicillium, Entyloma, and Cladosporium dominated the fungal community in the acidic geothermal springs, while the groups such as Penicillium, Engyodontium, and Schizophyllum controlled the fungal assemblages in the alkaline hot springs. The alpha-diversity indices and the abundant fungal taxa were significantly correlated with physicochemical factors of the hot springs particularly pH, temperature, and concentrations of Fe 2+ , NH 4 + , NO 2 -, and S 2- , suggesting that the diversity and distribution of fungal assemblages can be influenced by the complex environmental factors of hot springs.

Database of historically documented springs and spring flow measurements in Texas

USGS Publications Warehouse

Heitmuller, Franklin T.; Reece, Brian D.

2003-01-01

Springs are naturally occurring features that convey excess ground water to the land surface; they represent a transition from ground water to surface water. Water issues through one opening, multiple openings, or numerous seeps in the rock or soil. The database of this report provides information about springs and spring flow in Texas including spring names, identification numbers, location, and, if available, water source and use. This database does not include every spring in Texas, but is limited to an aggregation of selected digital and hard-copy data of the U.S. Geological Survey (USGS), the Texas Water Development Board (TWDB), and Capitol Environmental Services.

2. GENERAL VIEW FROM SOUTH SHOWING SOUTHWEST AND SOUTHEAST SIDES ...

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

2. GENERAL VIEW FROM SOUTH SHOWING SOUTHWEST AND SOUTHEAST SIDES AND CLERESTORY ARRANGEMENT - Sulphur Springs Methodist Campground, Sulphur Springs Road (Sulphur Springs), Sulphur Springs, Washington County, TN

Biogeographic congruency among bacterial communities from terrestrial sulfidic springs

PubMed Central

Headd, Brendan; Engel, Annette S.

2014-01-01

Terrestrial sulfidic springs support diverse microbial communities by serving as stable conduits for geochemically diverse and nutrient-rich subsurface waters. Microorganisms that colonize terrestrial springs likely originate from groundwater, but may also be sourced from the surface. As such, the biogeographic distribution of microbial communities inhabiting sulfidic springs should be controlled by a combination of spring geochemistry and surface and subsurface transport mechanisms, and not necessarily geographic proximity to other springs. We examined the bacterial diversity of seven springs to test the hypothesis that occurrence of taxonomically similar microbes, important to the sulfur cycle, at each spring is controlled by geochemistry. Complementary Sanger sequencing and 454 pyrosequencing of 16S rRNA genes retrieved five proteobacterial classes, and Bacteroidetes, Chlorobi, Chloroflexi, and Firmicutes phyla from all springs, which suggested the potential for a core sulfidic spring microbiome. Among the putative sulfide-oxidizing groups (Epsilonproteobacteria and Gammaproteobacteria), up to 83% of the sequences from geochemically similar springs clustered together. Abundant populations of Hydrogenimonas-like or Sulfurovum-like spp. (Epsilonproteobacteria) occurred with abundant Thiothrix and Thiofaba spp. (Gammaproteobacteria), but Arcobacter-like and Sulfurimonas spp. (Epsilonproteobacteria) occurred with less abundant gammaproteobacterial populations. These distribution patterns confirmed that geochemistry rather than biogeography regulates bacterial dominance at each spring. Potential biogeographic controls were related to paleogeologic sedimentation patterns that could control long-term microbial transport mechanisms that link surface and subsurface environments. Knowing the composition of a core sulfidic spring microbial community could provide a way to monitor diversity changes if a system is threatened by anthropogenic processes or climate change. PMID:25250021

Probability-based classifications for spatially characterizing the water temperatures and discharge rates of hot springs in the Tatun Volcanic Region, Taiwan.

PubMed

Jang, Cheng-Shin

2015-05-01

Accurately classifying the spatial features of the water temperatures and discharge rates of hot springs is crucial for environmental resources use and management. This study spatially characterized classifications of the water temperatures and discharge rates of hot springs in the Tatun Volcanic Region of Northern Taiwan by using indicator kriging (IK). The water temperatures and discharge rates of the springs were first assigned to high, moderate, and low categories according to the two thresholds of the proposed spring classification criteria. IK was then used to model the occurrence probabilities of the water temperatures and discharge rates of the springs and probabilistically determine their categories. Finally, nine combinations were acquired from the probability-based classifications for the spatial features of the water temperatures and discharge rates of the springs. Moreover, various combinations of spring water features were examined according to seven subzones of spring use in the study region. The research results reveal that probability-based classifications using IK provide practicable insights related to propagating the uncertainty of classifications according to the spatial features of the water temperatures and discharge rates of the springs. The springs in the Beitou (BT), Xingyi Road (XYR), Zhongshanlou (ZSL), and Lengshuikeng (LSK) subzones are suitable for supplying tourism hotels with a sufficient quantity of spring water because they have high or moderate discharge rates. Furthermore, natural hot springs in riverbeds and valleys should be developed in the Dingbeitou (DBT), ZSL, Xiayoukeng (XYK), and Macao (MC) subzones because of low discharge rates and low or moderate water temperatures.

Manufacture of conical springs with elastic medium technology improvement

NASA Astrophysics Data System (ADS)

Kurguzov, S. A.; Mikhailova, U. V.; Kalugina, O. B.

2018-01-01

This article considers the manufacturing technology improvement by using an elastic medium in the stamping tool forming space to improve the conical springs performance characteristics and reduce the costs of their production. Estimation technique of disk spring operational properties is developed by mathematical modeling of the compression process during the operation of a spring. A technique for optimizing the design parameters of a conical spring is developed, which ensures a minimum voltage value when operated in the edge of the spring opening.

Factors that Influence the Success of Male and Female Computer Programming Students in College

NASA Astrophysics Data System (ADS)

Clinkenbeard, Drew A.

As the demand for a technologically skilled work force grows, experience and skill in computer science have become increasingly valuable for college students. However, the number of students graduating with computer science degrees is not growing proportional to this need. Traditionally several groups are underrepresented in this field, notably women and students of color. This study investigated elements of computer science education that influence academic achievement in beginning computer programming courses. The goal of the study was to identify elements that increase success in computer programming courses. A 38-item questionnaire was developed and administered during the Spring 2016 semester at California State University Fullerton (CSUF). CSUF is an urban public university comprised of about 40,000 students. Data were collected from three beginning programming classes offered at CSUF. In total 411 questionnaires were collected resulting in a response rate of 58.63%. Data for the study were grouped into three broad categories of variables. These included academic and background variables; affective variables; and peer, mentor, and role-model variables. A conceptual model was developed to investigate how these variables might predict final course grade. Data were analyzed using statistical techniques such as linear regression, factor analysis, and path analysis. Ultimately this study found that peer interactions, comfort with computers, computer self-efficacy, self-concept, and perception of achievement were the best predictors of final course grade. In addition, the analyses showed that male students exhibited higher levels of computer self-efficacy and self-concept compared to female students, even when they achieved comparable course grades. Implications and explanations of these findings are explored, and potential policy changes are offered.

Physical characteristics and chemical quality of selected springs in parts of Juab, Millard, Tooele, and Utah counties, Utah

USGS Publications Warehouse

Wilberg, D.E.; Stolp, B.J.

1985-01-01

Hydrologic, geologic, and partial water quality data were collected at 90 selected springs in west-central Utah, and chemical analyses performed on water samples from 62 of the springs. Descriptions of the physiographic and geologic conditions, climate, and vegetation patterns for the study area are included. Allowable limits of certain chemical constituents in water for human and livestock consumption are included with the water quality data. Three classifications of springs were established based on physical characteristics of the springs, and chemical composition of the springflow: (1) mountain springs; (2) non-thermal valley springs, and (3) thermal valley springs. Mountain springs are in and near recharge areas, have seasonal variations of discharge and temperature, typically discharge from extrusive and metamorphic geohydrologic units, and generally discharge freshwater. Non-thermal valley springs are peripheral to recharge areas, have seasonal variations of discharge and temperature, typically discharge from a variety of geohydrologic units, and have variable water composition. Thermal valley springs are near topographic low areas of valleys , and have little seasonal variation of discharge or temperature. They typically discharge from unconsolidated deposits (but the discharge probably has flowed through buried carbonate geohydrologic units). They also have a considerable range of water composition that reflects the relative complexity of the groundwater system. (Author 's abstract)

Spring-mediated distraction enterogenesis in-continuity.

PubMed

Huynh, Nhan; Rouch, Joshua D; Scott, Andrew; Chiang, Elvin; Wu, Benjamin M; Shekherdimian, Shant; Dunn, James C Y

2016-12-01

Distraction enterogenesis has been investigated as a novel treatment for patients with short bowel syndrome (SBS) but has been limited by loss of intestinal length during restoration and need for multiple bowel surgeries. The feasibility of in-continuity, spring-mediated intestinal lengthening has yet to be demonstrated. Juvenile mini-Yucatan pigs underwent in-continuity placement of polycaprolactone (PCL) degradable springs within jejunum. Methods used to anchor the spring ends to the intestine included full-thickness sutures and a high-friction surface spring. Spring constant (k) was 6-15N/m. Bowel was examined for length and presence of spring at 1 to 4weeks. Animals tolerated in-continuity lengthening without bowel obstruction for up to 29days. In-continuity jejunum with springs demonstrated intestinal lengthening by 1.47-fold ±0.11. Five springs had detached prematurely, and lengthening could not be assessed. Histologically, in-continuity jejunum showed significantly increased crypt depth and muscularis thickness in comparison to normal jejunum. Self-expanding endoluminal springs placed in continuity could lengthen intestine without obstruction in a porcine model. This is the first study showing safety and efficacy of a self-expanding endoluminal device for distraction enterogenesis. This is proof-of-concept that in-continuity spring lengthening is feasible and demonstrates its therapeutic potential in SBS. Level 3. Copyright © 2016 Elsevier Inc. All rights reserved.

Large springs of east Tennessee

USGS Publications Warehouse

Sun, Pao-chang P.; Criner, J.H.; Poole, J.L.

1963-01-01

Springs constitute an important source of water in east Tennessee, and many individual springs are capable of supplying the large quantities needed for municipal and industrial supplies. Most of the springs in east Tennessee issue from solution openings and fractured and faulted zones in limestone and dolomite of the Knox Group, Chickamauga Limestone, and Conasauga Group. The ability of these rocks to yield a sustained flow of water to springs is dependent on a system of interconnected openings through which water can infiltrate from the land surface and move to points of natural discharge. Ninety springs were selected for detailed study, and 84 of these are analyzed in terms of magnitude and variability of discharge. Of the 84 springs analyzed, 4 flow at an average rate of 10 to 100 cfs (cubic feet per second), 62 at an average rate of 1 to 10 cfs, and 18 at an average rate of 1 cfs or less. Of the 90 springs, 75 are variable in their discharge; that is, the ratio of their fluctuations to their average discharges exceeds 100 percent. Mathematical analysis of the flow recession curve of Mill Spring near Jefferson City shows that the hydrologic system contributing to the flow of the spring has an effective capacity of about 70 million cubic feet of water. The rate of depletion of this volume of water, in the absence of significant precipitation, averages 0.0056 cfs per day between the time when the hydrologic system is full and the time when the spring ceases to flow. From such a curve it is possible to determine at any time the residual volume of water remaining in the system and the expected rate of decrease in discharge from that time to cessation of flow. Correlation of discharge measurements of 22 springs with those of Mill Spring shows that rough approximations of discharge can be projected for springs for which few measurements are available. Seventeen of the springs analyzed in this manner show good correlation with Mill Spring: that is, their coefficients of correlation were 0.70 or better as compared with a perfect correlation factor of 1.00.

A natural tracer investigation of the hydrological regime of Spring Creek Springs, the largest submarine spring system in Florida

NASA Astrophysics Data System (ADS)

Dimova, Natasha T.; Burnett, William C.; Speer, Kevin

2011-04-01

This work presents results from a nearly two-year monitoring of the hydrologic dynamics of the largest submarine spring system in Florida, Spring Creek Springs. During the summer of 2007 this spring system was observed to have significantly reduced flow due to persistent drought conditions. Our examination of the springs revealed that the salinity of the springs' waters had increased significantly, from 4 in 2004 to 33 in July 2007 with anomalous high radon ( 222Rn, t1/2=3.8 days) in surface water concentrations indicating substantial saltwater intrusion into the local aquifer. During our investigation from August 2007 to May 2009 we deployed on an almost monthly basis a continuous radon-in-water measurement system and monitored the salinity fluctuations in the discharge area. To evaluate the springs' freshwater flux we developed three different models: two of them are based on water velocity measurements and either salinity or 222Rn in the associated surface waters as groundwater tracers. The third approach used only salinity changes within the spring area. The three models showed good agreement and the results confirmed that the hydrologic regime of the system is strongly correlated to local precipitation and water table fluctuations with higher discharges after major rain events and very low, even reverse flow during prolong droughts. High flow spring conditions were observed twice during our study, in the early spring and mid-late summer of 2008. However the freshwater spring flux during our observation period never reached that reported from a 1970s value of 4.9×10 6 m 3/day. The maximum spring flow was estimated at about 3.0×10 6 m 3/day after heavy precipitation in February-March 2008. As a result of this storm (total of 173 mm) the salinity in the spring area dropped from about 27 to 2 in only two days. The radon-in-water concentrations dramatically increased in parallel, from about 330 Bq/m 3 to about 6600 Bq/m 3. Such a rapid response suggests a direct connection between the deep and the surficial aquifers.

76 FR 5303 - Proposed Amendment of Class E Airspace; Carrizo Springs, Glass Ranch Airport, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-31

...-0877; Airspace Docket No. 10-ASW-13] Proposed Amendment of Class E Airspace; Carrizo Springs, Glass... rulemaking (NPRM). SUMMARY: This action proposes to amend Class E airspace for the Carrizo Springs, Glass.... * * * * * ASW TX E5 Carrizo Springs, Glass Ranch Airport, TX [Amended] Carrizo Springs, Glass Ranch Airport, TX...

76 FR 23322 - Change in Bank Control Notices; Acquisitions of Shares of a Bank or Bank Holding Company

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-26

... Street, Dallas, Texas 75201-2272: 1. Jonathan Ross Kasling of Hughes Springs, Texas, Individually; Mayo Givens Kasling III of Hughes Springs, Texas, Individually; Jonathan Ross Kasling of Hughes Springs, Texas; Mayo Givens Kasling III of Hughes Springs, Texas; Mayo Givens Kasling, Jr. of Hughes Springs, Texas and...

Counterintuitive Behavior in Mechanical Networks

ERIC Educational Resources Information Center

Peters, Sarah; Vondracek, Mark

2012-01-01

Almost all introductory physics classes will, at some point, include springs and elastic forces. When studying such topics, it is interesting to consider the spring system shown in Fig. 1. In this system, two identical springs are arranged with the top of one spring anchored to the ceiling and the bottom of the second spring attached to a hanging…

49 CFR 570.8 - Suspension systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... cracked. Structural parts shall not be bent or damaged. Stabilizer bars shall be connected. Springs shall..., shall be installed on both front springs, both rear springs, or on all four springs. Shock absorber...

7. GENERAL VIEW OF INTERIOR OF MEETINGHOUSE FROM SOUTHEAST SHOWING ...

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

7. GENERAL VIEW OF INTERIOR OF MEETINGHOUSE FROM SOUTHEAST SHOWING CLERESTORY ARRANGEMENT AND SUPPORT SYSTEM - Sulphur Springs Methodist Campground, Sulphur Springs Road (Sulphur Springs), Sulphur Springs, Washington County, TN

49 CFR 570.8 - Suspension systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... cracked. Structural parts shall not be bent or damaged. Stabilizer bars shall be connected. Springs shall..., shall be installed on both front springs, both rear springs, or on all four springs. Shock absorber...

49 CFR 570.8 - Suspension systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... cracked. Structural parts shall not be bent or damaged. Stabilizer bars shall be connected. Springs shall..., shall be installed on both front springs, both rear springs, or on all four springs. Shock absorber...

49 CFR 570.8 - Suspension systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... cracked. Structural parts shall not be bent or damaged. Stabilizer bars shall be connected. Springs shall..., shall be installed on both front springs, both rear springs, or on all four springs. Shock absorber...

Force delivery of Ni-Ti coil springs.

PubMed

Manhartsberger, C; Seidenbusch, W

1996-01-01

Sentalloy springs (GAC, Central Islip, N.Y.) of the open and closed type were investigated with a special designed device. The closed coil springs were subjected to a tensile and the open coil springs to a compression test. After a first measurement, the springs were activated for a period of 4 weeks and then reinvestigated with the same procedure. It could be shown distinctly that, with the different coil springs, the force delivery given by the producer could be achieved only within certain limits. To remain in the martensitic plateau, changed activation ranges, and for the Sentalloy coil springs white and red of the open and closed type, also changed force deliveries had to be taken into account. There was a distinct decrease in force delivery between the first and second measurement. After considering the loading curves of all the Sentalloy coil springs and choosing the right activation range respective to the force delivery, it was found that the coil springs deliver a superior clinical behavior and open new treatment possibilities.

Hydrogeology and water chemistry of Infranz catchment springs, Bahir Dar Area, Lake Tana Basin, Ethiopia

NASA Astrophysics Data System (ADS)

Abera, F. N.

2017-12-01

The major springs in the Infranz catchment are a significant source of water for Bahir city and nearby villages, while they help to sustain Infranz River and the downstream wetlands. The aim of the research was to understand the hydrogeological conditions of these high-discharge springs, and to explain the hydrochemical composition of spring waters. Water samples from rainwater and springs were collected and analyzed and compared for major cations and anions. The hydrochemical data analysis showed that all water samples of the springs have freshwater chemistry, Ca-HCO3 type, while deep groundwater shows more evolved types. This indicates limited water-rock interaction and short residence time for the spring waters. The rise of NO3- and PO43- may indicate future water quality degradation unless the anthropogenic activities upgradient and nearby are restricted. The uptake of 75% of spring water for water supply of Bahir Dar results in wetland degradation. Key words: Spring water, Infranz River, Bahir Dar, Ethiopia, hydrochemistry

Preliminary examination of spring break alcohol use and related consequences.

PubMed

Lee, Christine M; Lewis, Melissa A; Neighbors, Clayton

2009-12-01

The authors examined the extent to which college student drinkers are at risk for experiencing negative alcohol-related consequences during Spring Break. A sample of first-year college student drinkers (N = 726) participated by completing an online survey assessing typical drinking, as well as Spring Break drinking and related consequences. Findings suggest Spring Break drinking was positively associated with alcohol-related consequences during Spring Break, even after controlling for sex and typical drinking. Furthermore, results indicated that typical drinking moderated the relationship between Spring Break drinking and expected zero-values (i.e., not reporting any Spring Break consequences), such that the association between Spring Break drinking and the likelihood of being a zero-score was less evident for those who are typically lighter drinkers. Identifying and examining temporal and contextually relevant events and associated drinking is critical for understanding and ultimately preventing extreme drinking and associated consequences associated with specific events like Spring Break, which place many students at high risk for experiencing acute harm. Copyright 2009 APA

Transient nature of Arctic spring systems driven by subglacial meltwater

NASA Astrophysics Data System (ADS)

Scheidegger, J. M.; Bense, V. F.; Grasby, S. E.

2012-06-01

In the High Arctic, supra- and proglacial springs occur at Borup Fiord Pass, Ellesmere Island. Spring waters are sulfur bearing and isotope analysis suggests springs are fed by deeply circulating glacial meltwater. However, the mechanism maintaining spring flow is unclear in these areas of thick permafrost which would hamper the discharge of deep groundwater to the surface. It has been hypothesized that fracture zones along faults focus groundwater which discharges initially underneath wet-based parts of the ice. With thinning ice, the spring head is exposed to surface temperatures, tens of degrees lower than temperatures of pressure melting, and permafrost starts to develop. Numerical modeling of coupled heat and fluid flow suggest that focused groundwater discharge should eventually be cut off by permafrost encroaching into the feeding channel of the spring. Nevertheless, our model simulations show that these springs can remain flowing for millennia depending on the initial flow rate and ambient surface temperature. These systems might provide a terrestrial analog for the possible occurrence of Martian springs recharged by polar ice caps.

A wearable robotic orthosis with a spring-assist actuator.

PubMed

Seungmin Jung; Chankyu Kim; Jisu Park; Dongyoub Yu; Jaehwan Park; Junho Choi

2016-08-01

This paper introduces a wearable robotic orthosis with spring-assist actuators, which is designed to assist people who have difficulty in walking. The spring-assist actuator consists of an electrical motor and a spring, which are attached to a rotational axis in parallel to each other. The spring-assist actuator is developed based on the analysis on the stiffness of the knee and hip joints during walking. "COWALK-Mobile," which is a wearable robotic orthosis, is developed using the spring-assist actuators to reduce the required motor torque during walking. The COWALK-Mobile has active hip and knee joints and passive ankle joints to provide assistive torque to the wearer. The required joint torque is generated by the spring as well as the electrical motor, which results in a decrease of maximum required torque for the motor. In order to evaluate the performance of the spring-assist actuator, experiments are carried out. The experiments show that the spring-assist actuators reduced the required motor torque during walking.