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1

33 CFR 263.26 - Small beach erosion control project authority (Section 103).  

Code of Federal Regulations, 2012 CFR

... 3 2012-07-01 2012-07-01 false Small beach erosion control project authority (Section 103). 263.26 Section...PROGRAMS Shore Protection Policy § 263.26 Small beach erosion control project authority (Section 103). (a)...

2012-07-01

2

33 CFR 263.26 - Small beach erosion control project authority (Section 103).  

Code of Federal Regulations, 2010 CFR

... 3 2010-07-01 2010-07-01 false Small beach erosion control project authority (Section 103). 263.26 Section...PROGRAMS Shore Protection Policy § 263.26 Small beach erosion control project authority (Section 103). (a)...

2010-07-01

3

33 CFR 263.26 - Small beach erosion control project authority (Section 103).  

... 3 2014-07-01 2014-07-01 false Small beach erosion control project authority (Section 103). 263.26 Section...PROGRAMS Shore Protection Policy § 263.26 Small beach erosion control project authority (Section 103). (a)...

2014-07-01

4

33 CFR 263.26 - Small beach erosion control project authority (Section 103).  

Code of Federal Regulations, 2011 CFR

... 3 2011-07-01 2011-07-01 false Small beach erosion control project authority (Section 103). 263.26 Section...PROGRAMS Shore Protection Policy § 263.26 Small beach erosion control project authority (Section 103). (a)...

2011-07-01

5

33 CFR 263.26 - Small beach erosion control project authority (Section 103).  

Code of Federal Regulations, 2013 CFR

... 3 2013-07-01 2013-07-01 false Small beach erosion control project authority (Section 103). 263.26 Section...PROGRAMS Shore Protection Policy § 263.26 Small beach erosion control project authority (Section 103). (a)...

2013-07-01

6

Targeting Erosion Control: Adoption of Erosion Control Practices. A Report from a National Research Project.  

ERIC Educational Resources Information Center

Research analyzed adoption of erosion control practices by farm operators in two counties in each of four states: Alabama, Missouri, Tennessee, and Washington. Analysis was based on farm survey data and technical and financial assistance information from county Soil Conservation Service (SCS) and Agricultural Stabilization and Conservation Service…

West, Peter; And Others

7

Erosion Control Progress in the HUA IDAHO SNAKE-PAYETTE RIVERS --HUA WATER QUALITY PROJECT FINAL REPORT  

E-print Network

Erosion Control Progress in the HUA IDAHO SNAKE-PAYETTE RIVERS -- HUA WATER QUALITY PROJECT FINAL HUAWater Quality Project encompassing Canyon, Gem, Payette, and Washington counties in southwestern Idaho. Washington Payette Gem Canyon BUL 808 The Idaho Snake-Payette Rivers Hydrologic Unit Water Quality Project

O'Laughlin, Jay

8

Erosion by water: vegetative control  

Technology Transfer Automated Retrieval System (TEKTRAN)

Vegetation controls erosion by dissipating the erosive forces of rainfall and runoff (erosivity - the strength of the forces causing erosion) and by reducing the susceptibility of soil to erosion (erodibility - how easily soil can be detached and transported). Vegetation alters the partitioning of r...

9

Weathering and Erosion Video Project  

NSDL National Science Digital Library

Using a digital video recorder, 6th grade students will create an informational video that teaches 4th grade (or 5th as an FCAT review) students about weathering and erosion using images from around the school and local areas. This will most likely be a long-term project, depending on how many digital video recorders and computers are available.

Amber Thibedeau

2012-07-25

10

Erosion Control for Local Roads  

E-print Network

Erosion Control Handbook for Local Roads M I N N E S OT A DEPARTME N T OF T R A N S PORTATION was extremely helpful in identifying key issues and concerns of those responsible for controlling erosion on low. This report does not constitute a standard, specification, or regulation. 2 #12;Table of Contents Erosion

Minnesota, University of

11

Ceramic corrosion/erosion project description  

SciTech Connect

As a part of the United States Department of Energy's High Temperature Turbine Technology Program, the Morgantown Energy Technology Center is participating in a Ceramics Corrosion/Erosion Materials Study. Objective is to create a technology base for ceramic materials which could be used by stationary gas power turbines operating with a high-temperature, coal-derived, low-Btu gas products of combustion environment. Two facilities are designed and installed to burn a varying low-Btu coal-derived gas in a controlled manner. This report contains the objectives and testing philosophy as well as the operating, specimen handling, and emergency procedures for the facilities. The facilities were checked out in August/September 1980. Testing is scheduled to begin in late 1980 with completion of 1000 hours of ceramic materials exposure to be completed by early 1981. Most of the enclosed is an update of two METC Information Releases (IR), i.e., IR 442 (1979) Test Plan for Ceramic Corrosion/Erosion Project, and IR 817 (1980) Ceramic Corrosion/Erosion Project Description.

Nakaishi, C.V.; Carpenter, L.K.

1981-02-01

12

Lincoln Park shoreline erosion control project: Monitoring for surface substrate, infaunal bivalves and eelgrass, 1993  

SciTech Connect

In 1988, the US Army Corps of Engineers and the City of Seattle placed material on the upper beach at Lincoln Park, in West Seattle, Washington. The fill served to mitigate shoreline erosion that had caused undercutting and collapse of the seawall in several places. A series of pre- and post-construction studies have been conducted to assess the impacts to marine biota of fill placement and movement of surface substrate. This study was designed to monitor infaunal bivalves and eelgrass from intertidal areas in and adjacent to the area of original fill placement. Findings from this survey were compared to previous survey results to determine (1) if recruitment of infaunal bivalves to the fill area has occurred, (2) if infaunal bivalve densities outside the fill area are stable, and (3) if eelgrass distribution and abundance have remained stable along the adjacent shoreline. To maximize comparability of findings from this survey with previous studies, sampling techniques, transects, and tidal elevations were consistent with previous studies at this site.

Antrim, L.D.; Thom, R.M.; Gardiner, W.W. [Battelle/Marine Sciences Lab., Sequim, WA (United States)

1993-09-01

13

Effectiveness of postfire erosion control treatments  

Technology Transfer Automated Retrieval System (TEKTRAN)

To mitigate potential postfire erosion and flooding, various erosion control treatments are applied on highly erodible areas with downstream resources in need of protection. Recent efforts to evaluate the effectiveness of postfire erosion mitigation treatments have used natural rainfall experiments ...

14

Soil Erosion Control After Wildfire  

NSDL National Science Digital Library

The potential for severe soil erosion is a consequence of wildfire because as a fire burns it destroys important plant material and the litter layer that stabilizes soil and slows water movement after severe rainstorms. This information sheet discusses how intense heat from fire can make soils hydrophobic, or water repellent, and identifies the actions landowners can take to minimize erosion after a fire.

15

Robotic weld overlay coatings for erosion control  

NASA Astrophysics Data System (ADS)

The erosion of materials by the impact of solid particles has received increasing attention during the past twenty years. Recently, research has been initiated with the event of advanced coal conversion processes in which erosion plays an important role. The resulting damage, termed Solid Particle Erosion (SPE), is of concern primarily because of the significantly increased operating costs which result in material failures. Reduced power plant efficiency due to solid particle erosion of boiler tubes and waterfalls has led to various methods to combat SPE. One method is to apply coatings to the components subjected to erosive environments. Protective weld overlay coatings are particularly advantageous in terms of coating quality. The weld overlay coatings are essentially immune to spallation due to a strong metallurgical bond with the substrate material. By using powder mixtures, multiple alloys can be mixed in order to achieve the best performance in an erosive environment. However, a review of the literature revealed a lack of information on weld overlay coating performance in erosive environments which makes the selection of weld overlay alloys a difficult task. The objective of this project is to determine the effects of weld overlay coating composition and microstructure on erosion resistance. These results will lead to a better understanding of erosion mitigation in CFB's.

16

Airphoto analysis of erosion control practices  

NASA Technical Reports Server (NTRS)

The Universal Soil Loss Equation (USLE) is a widely accepted tool for erosion prediction and conservation planning. In this study, airphoto analysis of color and color infrared 70 mm photography at a scale of 1:60,000 was used to determine the erosion control practice factor in the USLE. Information about contour tillage, contour strip cropping, and grass waterways was obtained from aerial photography for Pheasant Branch Creek watershed in Dane County, Wisconsin.

Morgan, K. M.; Morris-Jones, D. R.; Lee, G. B.; Kiefer, R. W.

1980-01-01

17

Updating Slope Topography During Erosion Simulations with the Water Erosion Prediction Project  

Microsoft Academic Search

The Water Erosion Prediction Project (WEPP) is a process-based continuous simulation erosion prediction model. However, WEPP currently assumes a fixed soil surface topography that does not change due to predicted detachment and\\/or deposition through a simulation period. While this approach might be satisfactory for slopes with uniform management, we hypothesized that long-term erosion predictions could be seriously altered by modifications

Jingcai Zhu; Seth M. Dabney; Dennis C. Flanagan

18

CONTROL OF GULLY EROSION USING STIFF GRASSES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Current practice for riparian gully erosion control involves blocking the gully with a structure comprised of an earthen embankment and a metal or plastic pipe. Measures involving native vegetation are more attractive for habitat recovery and economic reasons. To test the hypothesis that switchgra...

19

Soil Stabilizers to Control Wind Erosion1  

Microsoft Academic Search

The maintenance of our environment and the need to increase food produc- tion has prompted a search for materials and methods to stabilize soil surfaces against wind and water erosion. This paper discusses investigations on surface- applied materials to control soil movement by wind. Field and laboratory studies have established the following criteria for surface soil stabilizers: (i) 10070 of

D. V. ARMBRUST; LEON LYLES

20

Rainfall Controls Cascade Mountains' Erosion and Bedrock Uplift Patterns  

NSF Publications Database

... 703) 292-8552 dfountai@nsf.gov Rainfall Controls Cascade Mountains' Erosion and Bedrock Uplift ... The data strongly suggest that precipitation controls erosion rates across the Cascades, and that ...

21

7 CFR 3201.68 - Erosion control materials.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Erosion control materials. 3201.68 Section...PROCUREMENT Designated Items § 3201.68 Erosion control materials. (a) Definition...or other sites to prevent wind or water erosion of loose earth surfaces, which may...

2012-01-01

22

7 CFR 3201.68 - Erosion control materials.  

...2014-01-01 2014-01-01 false Erosion control materials. 3201.68 Section...PROCUREMENT Designated Items § 3201.68 Erosion control materials. (a) Definition...or other sites to prevent wind or water erosion of loose earth surfaces, which may...

2014-01-01

23

7 CFR 3201.68 - Erosion control materials.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Erosion control materials. 3201.68 Section...PROCUREMENT Designated Items § 3201.68 Erosion control materials. (a) Definition...or other sites to prevent wind or water erosion of loose earth surfaces, which may...

2013-01-01

24

Virginia Erosion and Sediment Control Handbook. Standards, Criteria and Guidelines.  

ERIC Educational Resources Information Center

Guidelines and technical standards for development of local erosion and sediment control programs and conservation standards to meet the goals established by the Virginia Erosion and Sediment Control law are presented in this handbook. Part I defines natural and manmade erosion, sedimentation, and the hazards of uncontrolled wear and damage to the…

Virginia State Soil and Water Conservation Commission, Richmond, VA.

25

Principles of Wind Erosion and its Control  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nearly sixty years after the Dust Bowl ended, wind erosion continues to threaten the sustainability of our nations' natural resources. This publication presents a review of the current state of wind erosion science by describing the problem of wind erosion, the physical basis of wind erosion proces...

26

Estimation of sediment-discharge reduction for two sites of the Yazoo River basin demonstration erosion control project, north-central Mississippi, 1985-94  

USGS Publications Warehouse

Sediment-discharge reduction was estimated at two Demonstration Erosion Control sites in north-central Mississippi for the period 1985 through 1994. Decreasing trends were detected in flow-adjusted sediment discharge at Hotopha Creek near Batesville for the study period. The annual reduction in sediment discharge at this site was about 7 percent (0.68 ton per day per year). Decreasing trends were also detected in flow- adjusted sediment discharge at Otoucalofa Creek Canal near Water Valley for the study period. The annual reduction in sediment discharge at this site was about 11 percent (5.33 tons per day per year). The computations used to estimate sediment-discharge reduction were based on time series of instantaneous sediment discharges for the study period. Non-parametric procedures were used to compute trends in sediment discharge and to quantify reductions over time at the two sites. Parametric procedures were then used to verify the non-parametric results.

Rebich, R.A.

1995-01-01

27

Geospatial application of the Water Erosion Prediction Project (WEPP) model  

Technology Transfer Automated Retrieval System (TEKTRAN)

At the hillslope profile and/or field scale, a simple Windows graphical user interface (GUI) is available to easily specify the slope, soil, and management inputs for application of the USDA Water Erosion Prediction Project (WEPP) model. Likewise, basic small watershed configurations of a few hillsl...

28

Robotic weld overlay coatings for erosion control  

NASA Astrophysics Data System (ADS)

Research is being conducted to develop criteria for selecting weld overlay coatings for erosion mitigation in circulated fluidized beds. Twelve weld overlay alloys were deposited on 1018 steel substrates using plasma arc welding. Ten samples from each coating were prepared for erosion testing. All selected coatings were erosion tested at 400C and their erosion resistance and microstructure evaluated. Steady state erosion rates were similar for several weld overlay coatings (Ultimet, Inconel-625, Iron-Aluminide, 316L SS, and High Chromium Cast Iron) and were considerably lower than the remaining coating evaluated. These coatings had different base (Co, Fe, Ni-base). No correlations were found between room temperature microhardness of the weld overlay coatings and their erosion resistance at elevated temperature, although this criteria is often thought to be an indicator of erosion resistance. It was suggested that the coatings that showed similar erosion rates may have similar mechanical properties such as fracture strength, toughness and work hardening rates at this temperature. During the past quarter, Iron-Aluminide, Inconel-625, and 316L SS coatings were selected for more detailed investigations based upon the preliminary erosion test results. Microhardness tests were performed on eroded samples to determine the size of the work hardened zone and change in coatings hardness due to erosion. The work hardened zone was correlated with erosion resistance of the coatings. Additional Iron-Aluminide, Inconel-625, and 316L SS coatings were deposited on 1018 steel substrates.

Levin, B. F.; Dupont, J. N.; Marder, A. R.

1994-01-01

29

Gully erosion: Impacts, factors and control  

Microsoft Academic Search

Gully erosion attracts increasing attention from scientists as reflected by two recent international meetings [Poesen and Valentin (Eds.), Catena 50 (2–4), 87–564; Li et al., 2004. Gully Erosion Under Global Change. Sichuan Science Technology Press, Chengu, China, 354 pp.]. This growing interest is associated with the increasing concern over off-site impacts caused by soil erosion at larger spatial scales than

C. Valentin; J. Poesen; Yong Li

2005-01-01

30

Poplars and willows for soil erosion control in New Zealand  

Microsoft Academic Search

Poplars (Populus) and willows (Salix) are exotic to New Zealand and have been introduced and cultivated over the last 160 years, for soil erosion control on pastoral hill country, riverbank protection, shade, windbreaks and woodlot forestry. During the 1960s and 1970s over two million poplars were planted in government-subsidised erosion control schemes. Planting techniques and patterns are discussed. This type

A. G Wilkinson

1999-01-01

31

Aging effects of environmental factors on rolled erosion control products  

E-print Network

of MASTER OF SCIENCE December 2005 Major Subject: Civil Engineering AGING EFFECTS OF ENVIRONMENTAL FACTORS ON ROLLED EROSION CONTROL PRODUCTS A Thesis by SUMEE KHANNA Submitted to the Office of Graduate..., David V. Rosowsky December 2005 Major Subject: Civil Engineering iii ABSTRACT Aging Effects of Environmental Factors on Rolled Erosion Control Products. (December 2005) Sumee Khanna, B. E., Datta Meghe College...

Khanna, Sumee

2007-04-25

32

Improving frost-simulation subroutines of the Water Erosion Prediction Project (WEPP) model  

Technology Transfer Automated Retrieval System (TEKTRAN)

Erosion models play an important role in assessing the influence of human activities on the environment. For cold areas, adequate frost simulation is crucial for predicting surface runoff and water erosion. The Water Erosion Prediction Project (WEPP) model, physically-based erosion-prediction softwa...

33

Weld overlay coatings for erosion control  

SciTech Connect

A literature review was made. In spite of similarities between abrasive wear and solid particle erosion, weld overlay hardfacing alloys that exhibit high abrasion resistance may not necessarily have good erosion resistance. The performance of weld overlay hardfacing alloys in erosive environments has not been studied in detail. It is believed that primary-solidified hard phases such as carbides and intermetallic compounds have a strong influence on erosion resistance of weld overlay hardfacing alloys. However, relationships between size, shape, and volume fraction of hard phases in a hardfacing alloys and erosion resistance were not established. Almost all hardfacing alloys can be separated into two major groups based upon chemical compositions of the primary solidified hard phases: (a) carbide hardening alloys (Co-base/carbide, WC-Co and some Fe base superalloys); and (b) intermetallic hardening alloys (Ni-base alloys, austenitic steels, iron-aluminides).

Levin, B.; DuPont, J.N.; Marder, A.R.

1993-03-03

34

Cloud forest restoration for erosion control in a Kichwa community of the Ecuadorian central Andes Mountains  

NASA Astrophysics Data System (ADS)

The Denver Professional Chapter of Engineers Without Borders (EWB) has begun conducting erosion control projects in the Kichwa communities of Malingua Pamba in the Andes Mountains south of Quito, Ecuador. In many high elevation areas in this region, erosion of volcanic soils on steep hillsides (i.e., < 40%) is severe and often associated with roads, water supply systems, and loss of native cloud forests followed by burning and cultivation of food crops. Following a 2011 investigation of over 75 erosion sites, the multidisciplinary Erosion Control team traveled to Malingua Pamba in October 2012 to conduct final design and project implementation at 5 sites. In partnership with the local communities, we installed woody cloud forest species, grass (sig-sig) contour hedges, erosion matting, and rock structures (toe walls, plunge pools, bank armoring, cross vanes, contour infiltration ditches, etc.) to reduce incision rates and risk of slump failures, facilitate aggradation, and hasten revegetation. In keeping with the EWB goal of project sustainability, we used primarily locally available resources. High school students of the community grew 5000 native trees and some naturalized shrubs in a nursery started by the school principal, hand weavers produced jute erosion mats, and rocks were provided by a nearby quarry. Where possible, local rock was harvested from landslide areas and other local erosion features. Based on follow up reports and photographs from the community and EWB travelers, the approach of using locally available materials installed by the community is successful; plants are growing well and erosion control structures have remained in place throughout the November to April rainy season. The community has continued planting native vegetation at several additional erosion sites. Formal monitoring will be conducted in October 2013, followed by analysis of data to determine if induced meandering and other low-maintenance erosion control techniques are working as planned. For comparison of techniques, we will consider installing check dams in comparable gullies. The October 2013 project will also focus on training the community how to conduct erosion control site assessments, design site-appropriate structures, and implement erosion control and revegetation plans. Following the training, the community will teach these skills to adjacent villages.

Backus, L.; Giordanengo, J.; Sacatoro, I.

2013-12-01

35

Erosion  

NSDL National Science Digital Library

Soil erosion is a global problem. Each year, erosion costs billions of dollars in loss of land productivity, damage from soil sediment deposition and subsequent restoration costs, and harm to plant, animal, and human health due to air and water pollution. This lesson will consider the impacts of erosion at local, regional, national, and international levels. It will discuss how erosion occurs and the main factors that contribute to erosion. In addition, the different types of water and wind erosion will be discussed.The lesson is written to target educational needs of lower level undergraduate students and is open for use by the public and educational institutions. Depending on the goals/objectives of a course, training, workshop, part or all sections of the lesson could be used.

36

48 CFR 452.236-74 - Control of Erosion, Sedimentation, and Pollution.  

Code of Federal Regulations, 2013 CFR

...Control of Erosion, Sedimentation, and Pollution. 452.236-74 Section 452.236-74...Control of Erosion, Sedimentation, and Pollution. As prescribed in 436.574, insert...Control of Erosion, Sedimentation, and Pollution (NOV 1996) (a) Operations...

2013-10-01

37

48 CFR 436.574 - Control of erosion, sedimentation, and pollution.  

...Control of erosion, sedimentation, and pollution. 436.574 Section 436.574 ...Control of erosion, sedimentation, and pollution. The contracting officer shall insert...Control of Erosion, Sedimentation and Pollution, if there is a need for applying...

2014-10-01

38

48 CFR 436.574 - Control of erosion, sedimentation, and pollution.  

Code of Federal Regulations, 2013 CFR

...Control of erosion, sedimentation, and pollution. 436.574 Section 436.574 ...Control of erosion, sedimentation, and pollution. The contracting officer shall insert...Control of Erosion, Sedimentation and Pollution, if there is a need for applying...

2013-10-01

39

48 CFR 452.236-74 - Control of Erosion, Sedimentation, and Pollution.  

...Control of Erosion, Sedimentation, and Pollution. 452.236-74 Section 452.236-74...Control of Erosion, Sedimentation, and Pollution. As prescribed in 436.574, insert...Control of Erosion, Sedimentation, and Pollution (NOV 1996) (a) Operations...

2014-10-01

40

48 CFR 452.236-74 - Control of Erosion, Sedimentation, and Pollution.  

Code of Federal Regulations, 2012 CFR

...Control of Erosion, Sedimentation, and Pollution. 452.236-74 Section 452.236-74...Control of Erosion, Sedimentation, and Pollution. As prescribed in 436.574, insert...Control of Erosion, Sedimentation, and Pollution (NOV 1996) (a) Operations...

2012-10-01

41

48 CFR 436.574 - Control of erosion, sedimentation, and pollution.  

Code of Federal Regulations, 2012 CFR

...Control of erosion, sedimentation, and pollution. 436.574 Section 436.574 ...Control of erosion, sedimentation, and pollution. The contracting officer shall insert...Control of Erosion, Sedimentation and Pollution, if there is a need for applying...

2012-10-01

42

48 CFR 436.574 - Control of erosion, sedimentation, and pollution.  

Code of Federal Regulations, 2011 CFR

...Control of erosion, sedimentation, and pollution. 436.574 Section 436.574 ...Control of erosion, sedimentation, and pollution. The contracting officer shall insert...Control of Erosion, Sedimentation and Pollution, if there is a need for applying...

2011-10-01

43

48 CFR 452.236-74 - Control of Erosion, Sedimentation, and Pollution.  

Code of Federal Regulations, 2011 CFR

...Control of Erosion, Sedimentation, and Pollution. 452.236-74 Section 452.236-74...Control of Erosion, Sedimentation, and Pollution. As prescribed in 436.574, insert...Control of Erosion, Sedimentation, and Pollution (NOV 1996) (a) Operations...

2011-10-01

44

18 CFR 1304.202 - General sediment and erosion control provisions.  

...2014-04-01 false General sediment and erosion control provisions. 1304.202 Section... § 1304.202 General sediment and erosion control provisions. (a) During construction...activities, TVA shall require that appropriate erosion and sediment control measures be...

2014-04-01

45

18 CFR 1304.202 - General sediment and erosion control provisions.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false General sediment and erosion control provisions. 1304.202 Section... § 1304.202 General sediment and erosion control provisions. (a) During construction...activities, TVA shall require that appropriate erosion and sediment control measures be...

2010-04-01

46

48 CFR 452.236-74 - Control of Erosion, Sedimentation, and Pollution.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Control of Erosion, Sedimentation, and Pollution. 452.236-74...452.236-74 Control of Erosion, Sedimentation, and Pollution. As prescribed...following clause: Control of Erosion, Sedimentation, and Pollution (NOV 1996)...

2010-10-01

47

Erosion  

NSDL National Science Digital Library

In this activity, learners model erosion using a clear shoebox and sand or soil. Learners observe and discuss wind and water erosion in action and determine what effect sod and rocks have on their model. They examine gullies, valleys, landslides, and waves. During the investigation, learners draw diagrams of what they see. Later in the activity, learners take a walking field trip and look for evidence of erosion. They record their observations and explanations in a science log.

2012-06-26

48

DEMONSTRATION OF EROSION AND SEDIMENT CONTROL TECHNOLOGY. LAKE TAHOE REGION OF CALIFORNIA  

EPA Science Inventory

A three-year project was conducted by the California State Water Resources Control Board to determine methods of preventing and correcting erosion problems which severely effect the quality of the waters of the State of California. Two-project sites were chosen in the vicinity of...

49

Management of Winter Soil Temperatures to Control Streambank Erosion  

E-print Network

Management of Winter Soil Temperatures to Control Streambank Erosion CAROLYN BORN! Range, Wildlife Review Ice formation in the horizontal soil surface and the resultant heaving and erosion have long been and Forestry Department University of Nevada-Reno Reno, Nevada 89512 USA Abstract.-Winter soil temperatures

50

Erosion  

NSDL National Science Digital Library

Students will design and conduct an open-ended investigation using a variety of earth materials to answer a question posed by the teacher: How does the erosion of sand compare with the erosion of gravel? After producing evidence that addresses this question, they will generate their own question that could be answered with further scientific inquiry.

PALS-Performance Assessment Links in Science

2012-04-24

51

Leucaena— A promising soil-erosion-control plant  

Microsoft Academic Search

This woody legume, originally native to Mexico but now naturalized in Arizona, Florida and Texas, has been extensively used\\u000a in Indonesia for soil erosion control and should be similarly employed in our Southern States.

M. J. Dijkman

1950-01-01

52

International Erosion Control Association www.ieca.org  

E-print Network

, agricultural science, or marine science.) Applicant must have a cumulative undergraduate GPA of 2.75 (on a 4.0. Applicant must have a career direction related to the erosion and sediment control industry. (Possible

Ma, Lena

53

Effects of Rising Relative Energy Prices on Soil Erosion and Its Control  

Microsoft Academic Search

Efforts to develop public programs to control soil erosion should not ignore other economic trends which may affect soil erosion. This programming analysis considers the impact of rising relative energy prices on cropland erosion in conjunction with alternative erosion control policies. Higher relative energy prices are found to reduce soil erosion significantly, complement soil loss restriction policies, and have an

John Miranowski; L. Zinser; James S. Shortle; Michael J. Monson

1985-01-01

54

Crop residues: energy production or erosion control  

Microsoft Academic Search

Research report:USDA scientists conducted a study to determine: in which regions of the U.S. crop residues are produced in abundant quantities; what plant nutrients the residues contain; and the effects of tillage and residue management on wind and water erosion and on water runoff. The scientists also estimated how much residue could be removed from the land without exceeding soil

2009-01-01

55

Adapting the Water Erosion Prediction Project (WEPP) model for forest applications  

Microsoft Academic Search

summary There has been an increasing public concern over forest stream pollution by excessive sedimentation due to natural or human disturbances. Adequate erosion simulation tools are needed for sound management of forest resources. The Water Erosion Prediction Project (WEPP) watershed model has proved useful in forest applications where Hortonian flow is the major form of runoff, such as modeling erosion

Shuhui Dun; Joan Q. Wu; William J. Elliot; Peter R. Robichaud; Dennis C. Flanagan; James R. Frankenberger; Robert E. Brown; Arthur C. Xu

2009-01-01

56

Using a Stream Table to Investigate Erosion Control  

NSDL National Science Digital Library

This activity will introduce students to water-induced topsoil erosion and different ways to control it. Using a stream table (prepared by the teacher), they will vary the surface of the 'soil', and the height of the table, pour in water, and observe sheet, rill, and gully erosion. They can also investigate the effects of check dams (by plugging gullies with pebbles), observe the results of contour plowing, and test the effectiveness of different types of mulch (straw, shredded paper, pine needles, etc.) in preventing erosion. Instructions for constructing a stream table, a student worksheet, and discussion questions are provided.

2005-10-06

57

Controlling template erosion with advanced cleaning methods  

NASA Astrophysics Data System (ADS)

We studied the erosion and feature stability of fused silica patterns under different template cleaning conditions. The conventional SPM cleaning is compared with an advanced non-acid process. Spectroscopic ellipsometry optical critical dimension (SE-OCD) measurements were used to characterize the changes in pattern profile with good sensitivity. This study confirmed the erosion of the silica patterns in the traditional acid-based SPM cleaning mixture (H2SO4+H2O2) at a rate of ~0.1nm per cleaning cycle. The advanced non-acid clean process however only showed CD shift of ~0.01nm per clean. Contamination removal & pattern integrity of sensitive 20nm features under MegaSonic assisted cleaning is also demonstrated.

Singh, SherJang; Yu, Zhaoning; Wähler, Tobias; Kurataka, Nobuo; Gauzner, Gene; Wang, Hongying; Yang, Henry; Hsu, Yautzong; Lee, Kim; Kuo, David; Dress, Peter

2012-03-01

58

ACOUSTIC PROFILING OF SEDIMENT ACCUMULATION IN THREE SMALL EROSION CONTROL RESERVOIRS IN NORTH MISSISSIPPI  

Technology Transfer Automated Retrieval System (TEKTRAN)

In Northern Mississippi, as part of a preventative erosion control program, the Yazoo-Little Tallahatchie Project (YLTP) created a system of small dams and reservoirs to regulate stream flow and to stop the movement of sediment over large distances. These structures were designed to have a lifetime ...

59

Adapting WEPP (Water Erosion Prediction Project) for forest watershed erosion modeling  

Technology Transfer Automated Retrieval System (TEKTRAN)

There has been an increasing public concern over forest stream pollution by excessive sedimentation resulting from human activities. Adequate and reliable erosion simulation tools are urgently needed for sound forest resources management. Computer models for predicting watershed runoff and erosion h...

60

Geologic controls of erosion and sedimentation on Mars  

NASA Technical Reports Server (NTRS)

Because Mars has had a history of diverse erosional and depositional styles, a variety of erosional landforms and sedimentary deposits can be seen on Viking orbiter images. Here we review how geologic processes involving rock, water, and structure have controlled erosion and sedimentation on Mars. Additionally, we review how further studies will help refine our understanding of these processes.

Tanaka, K. L.; Dohm, J. M.; Carr, M. H.

1993-01-01

61

Cover crops for erosion control in bioenergy hardwood plantations  

SciTech Connect

The use of cover crops between tree rows has been suggested as a means of reducing soil erosion in short-rotation woody crops (SRWC) plantations for bioenergy production. This study is designed to test whether cover crops could reduce erosion without significantly reducing the growth and biomass yield of sweetgum (Liquidambar styraciflua L.) planted as the SRWC at a 1.5 X 3 in spacing. Four cover crops, winter rye grass (Lolium multigeonum L., a winter annual grass); tall fescue (Fescuta eliator L., a winter perennial grass); crimson clover (Trifolium incarnatum L., a winter annual legume); and interstate sericea (Lespedeza ameata L., a growing season perennial legume), are tested at two different strip widths (1.22 and 2.44 m) as well as a control with complete competition control. Small berms were built to direct runoff to a sediment fence installed at the down slope ends of each plot. Soil erosion is measured by sediment accumulation near the fence. Height, ground-line diameter and crown width of trees were measured on a monthly basis. During the first growing season all cover crops reduced growth of trees. There were some significant differences among cover crop regimes. Slight differences in soil erosion were detected during the first growing season. The control plots lost more soil per hectare than cover crops, however, strip widths and cover crops did not show any significant difference.

Malik, R.K.; Green, T.H.; Mays, D. [Alabama A& M Univ., Normal, AL (United States)] [and others

1996-12-31

62

A. PROJECT SUMMARY. EROSION BENEATH THE LAURENTIDE ICE SHEET, AND ITS ROLE IN  

E-print Network

of the Quaternary ice ages (Clark and Pollard, 1998). We intuitivly associate the scoured landscapes of the northern EROSION BENEATH THE LAURENTIDE ICE SHEET, AND ITS ROLE IN PLEISTOCENE ICE AGE DYNAMICS PrincipalA-1 A. PROJECT SUMMARY. EROSION BENEATH THE LAURENTIDE ICE SHEET, AND ITS ROLE IN PLEISTOCENE ICE

Stone, John

63

Adapting the Water Erosion Prediction Project (WEPP) Model for Forest Applications  

Technology Transfer Automated Retrieval System (TEKTRAN)

There has been an increasing public concern over forest stream pollution by excessive sedimentation due to natural or human disturbances. Adequate erosion simulation tools are needed for sound management of forest resources. The Water Erosion Prediction Project (WEPP) watershed model has proved usef...

64

A comparison of erosion and water pollution control strategies for an agricultural watershed  

Microsoft Academic Search

The effectiveness and efficiency of two erosion control strategies and one water pollution control (riparian) strategy are compared for Idaho's Tom Beall watershed. Erosion control strategies maximize annualized net returns per hectare on each field and restrict field erosion rates to no more than 11.2 or 16.8 tons per hectare. The riparian strategy uses good vegetative cover on all fields

Tony Prato; Hongqi Shi

1990-01-01

65

48 CFR 436.574 - Control of erosion, sedimentation, and pollution.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Control of erosion, sedimentation, and pollution. 436.574 Section... 436.574 Control of erosion, sedimentation, and pollution. The contracting...452.236-74, Control of Erosion, Sedimentation and Pollution, if there is a need...

2010-10-01

66

A Comparison of Erosion and Water Pollution Control Strategies for an Agricultural Watershed  

Microsoft Academic Search

The effectiveness and efficiency of two erosion control strategies and one water pollution control (riparian) strategy are compared for Idaho's Tom Beall watershed. Erosion control strategies maximize annualized net returns per hectare on each field and restrict field erosion rates to no more than 11.2 or 16.8 tons per hectare. The riparian strategy uses good vegetative cover on all fields

Tony Prato; Hongqi Shi

1990-01-01

67

Soil Erosion and Sediment Production on Watershed Landscapes: Processes and Control  

E-print Network

Soil Erosion and Sediment Production on Watershed Landscapes: Processes and Control Authors: Peter Erosion and Sediment Production on Watershed Landscapes: Processes, Prevention, and Control #12;Authors, Scientific and Cultural Organizations (UNESCO). ISBN 978-92-9089-190-1- Soil Erosion and Sediment Production

68

ERDC/CHLTR-12-11 Erosion Control and Environment Restoration  

E-print Network

ERDC/CHLTR-12-11 Erosion Control and Environment Restoration Plan Development, Matagorda County Erosion Control and Environment Restoration Plan Development, Matagorda County, Texas Phase 1: Preliminary- ment of conceptual alternatives to reduce beach erosion at two sites in Matagorda County. Sargent Beach

US Army Corps of Engineers

69

Erosion control at construction sites on red clay soils  

NASA Astrophysics Data System (ADS)

Five single-treatment methods used to stabilize seeded areas at urban and highway construction sites (asphalt-tacked straw, jute netting, mulch blanket, wood chips, excelsior blanket) were tested for their ability to control erosion of red clay soils by comparisons with exposed sites and multiple treatments. Sediment in runoff from experimental plots was characterized during low and high intensity precipitation from natural rainfall episodes during April, May, and June. Reductions in the total sediment concentration of runoff ranged from 28 percent (asphalt-tacked straw, 50 percent slope) to 90 percent (multiple treatments, 40 percent slope), with ?85 percent of the eroded material composed of particles <0.04 mm in diameter. Larger size fractions were effectively reduced by all treatments tested regardless of slope (?70 percent decrease). Established grass cover exceeded 90 percent on all plots after 60 days, but sediment release remained similar, attributable to high intensity rainfall, poor establishment of root systems, and piping on plots treated with tacked straw or jute netting. Results indicate that current stabilization methods shift sediment compostion toward a smaller particle size, causing single treatments to be minimally effective for controlling erosion of the major component of red clay soils. Because small particles have the greatest direct effect on aquatic biota, certain impacts of sedimentation may not be measurably lessened by single treatments in regions where red clays predominate even though the total sediment load is reduced by as much as 75 percent. Clearly, a multiple-treatment approach offers significantly greater control of erosion on red clay soils, however, current economic and construction policy represents a substantial deterrent to implementation.

Lemly, A. Dennis

1982-07-01

70

Control of fan erosion in coal-fired power plants, Phase 2: Final report  

Microsoft Academic Search

The Electric Power Research Institute contracted with Westinghouse to address the problems electric utilities experience caused by fan erosion. The objective of this phase of the research program was to understand how to control erosion damage to coal-fired power plant fans by: Developing fan design modifications that raise the tolerance of fans to fly-ash erosion and that simultaneously improve fan

E. F. Sverdrup; L. Albertin; R. M. Chamberlin; N. J. DAmico; M. A. El Masri; A. D. Glasser; M. Menguturk; A. Rane; R. Racki; W. J. Petlevich

1988-01-01

71

GEOLOGY, November 2009 975 Climate controls erosion and weathering on soil-mantled land-  

E-print Network

GEOLOGY, November 2009 975 ABSTRACT Climate controls erosion and weathering on soil-mantled land, and surface erosion driven by overland flow at high eleva- tion. Soil production rates from cosmogenic 10 different climates can shape hillslopes by driving processes of erosion and weathering. INTRODUCTION Soils

Heimsath, Arjun M.

72

Evaluation of Erosion Control Products With and Without Added Polyacrylamide  

NASA Astrophysics Data System (ADS)

Polyacrylamide (PAM) has been demonstrated to greatly reduce erosion in furrow irrigation, but much less is known about its effectiveness on the much steeper slopes typical of construction sites. The purpose of this study was to determine if anionic PAM would enhance erosion control either alone on bare soil or in combination with four types of ground covers commonly used for grass establishment: straw, straw erosion control blanket (ECB), wood fiber, and mechanically bonded fiber matrix (MBFM). Tests were conducted under natural rainfall and vegetation on a 4 percent slope (bare soil, straw, ECB, and MBFM) or using a rainfall simulator (bare soil, straw, wood fiber, MBFM) on either 10 percent or 20 percent slope on three different soil substrates. All ground cover treatments were evaluated with and without PAM applied in solution at 19 kg/ha. The straw, ECB, and MBFM significantly reduced runoff volume, average turbidity, and total sediment lost over five rainfall events on the vegetated plots. The addition of PAM to ground covers only occasionally had significant effects on runoff parameters but did significantly increase vegetative coverage overall. The rainfall simulator tests produced similar results after four events, with the straw, wood fiber, and MBFM all having significantly lower turbidity than the bare soil. The PAM significantly reduced turbidity for both the first and second events but did not consistently improve runoff quality after multiple rainfall events for any ground cover-soil combinations tested. Separate tests of PAM applied before or after straw did not indicate a clear advantage of either approach, but runoff turbidity was often significantly reduced with PAM, especially at the 20 percent slope. Turbidity reductions were attributed to flocculation of eroded sediment.

McLaughlin, Richard A.; Brown, Tabitha T.

2006-06-01

73

Projected rainfall erosivity changes under climate change from multimodel and multiscenario projections in Northeast China  

Technology Transfer Automated Retrieval System (TEKTRAN)

Future changes in precipitation will induce changes in the erosive power of rainfall and hence changes in soil erosion rates. In this study we calculated downscaled mean annual precipitation and USLE rainfall erosivity (R) for time periods 2030 through 2059 and 2070 through 2099 in Northeast China u...

74

Project management controls  

SciTech Connect

Project management controls are utilized to enhance the probability that a project will be successful. The control system used by a project manager can take many forms and can be applied at different times to varying degrees on a given project depending upon its complexity. The Consolidated Incineration Facility (CIF) is one project of many at the Savannah River Site (SRS). The United States Department of Energy Order 4700.1 is a project management system that is applied on a site-wide basis, thus including the CIF. The control system required by this order is proceduralized to ensure that it is applied in a consistent manner and will produce reliable results. These results provide the project manager with a correlation of both costs and schedule within the defined scope to adequately asses the status of the project. This is an iterative process and can be simply stated: plan, actual, variance, corrective action, prediction, and revision. This paper presents the basis for the project management controls applied at the Savannah River Site.

Hardin, D.S. [Bechtel Savannah River Inc., Savannah River Site, Aiken, SC (United States); Carnes, W.S. [Westinghouse Savannah River Co., Aiken, SC (United States)

1990-12-31

75

Project management controls  

SciTech Connect

Project management controls are utilized to enhance the probability that a project will be successful. The control system used by a project manager can take many forms and can be applied at different times to varying degrees on a given project depending upon its complexity. The Consolidated Incineration Facility (CIF) is one project of many at the Savannah River Site (SRS). The United States Department of Energy Order 4700.1 is a project management system that is applied on a site-wide basis, thus including the CIF. The control system required by this order is proceduralized to ensure that it is applied in a consistent manner and will produce reliable results. These results provide the project manager with a correlation of both costs and schedule within the defined scope to adequately asses the status of the project. This is an iterative process and can be simply stated: plan, actual, variance, corrective action, prediction, and revision. This paper presents the basis for the project management controls applied at the Savannah River Site.

Hardin, D.S. (Bechtel Savannah River Inc., Savannah River Site, Aiken, SC (United States)); Carnes, W.S. (Westinghouse Savannah River Co., Aiken, SC (United States))

1990-01-01

76

A Comparison of Erosion and Water Pollution Control Strategies for an Agricultural Watershed  

NASA Astrophysics Data System (ADS)

The effectiveness and efficiency of two erosion control strategies and one water pollution control (riparian) strategy are compared for Idaho's Tom Beall watershed. Erosion control strategies maximize annualized net returns per hectare on each field and restrict field erosion rates to no more than 11.2 or 16.8 tons per hectare. The riparian strategy uses good vegetative cover on all fields adjacent to the creek and in noncropland areas and the resource management system that maximizes annualized net returns per hectare on remaining fields. The Agricultural Nonpoint Source Pollution model is used to simulate the levels and concentrations of sediment, nitrogen, phosphorus, and chemical oxygen demand at the outlet of the watershed. Erosion control strategies generate less total erosion and water pollution but are less efficient than the riparian strategy. The riparian strategy is less equitable for farmers than the erosion control strategies.

Prato, Tony; Shi, Hongqi

1990-02-01

77

Backshore sill beach and dune erosion control system  

SciTech Connect

A backshore sill beach and dune erosion control system is described comprising: a supporting protective apron formed of weather and water resistant cloth. The apron includes a flat base portion and an angularly sloped portion extending seaward of the base portion, a toe scour anchor tube connected to the seaward end of the apron sloped portion, and longitudinal sand-filled geotextile containers placed upon the apron base portion each extending longitudinally shore parallel to the incoming surf. The sand-filled geotextile containers are specifically placed upon the beach in a pyramidal longitudinally extending shore parallel relation to an area being protected whereby wave action impacts upon relatively soft surfaces of the containers and is dissipated before normally impacting surfaces that would otherwise be eroded.

Sample, J.W.

1988-03-08

78

Current projects in Fuzzy Control  

NASA Technical Reports Server (NTRS)

Viewgraphs on current projects in fuzzy control are presented. Three projects on helicopter flight control are discussed. The projects are (1) radio control by oral instructions; (2) automatic autorotation entry in engine failure; and (3) unmanned helicopter for sea rescue.

Sugeno, Michio

1990-01-01

79

Beach erosion control study at Pass Christian. [using remote sensors and satellite observation  

NASA Technical Reports Server (NTRS)

The methods of measuring the existence of erosion and the effects of sand stabilization control systems are described. The mechanics of sand movement, the nature of sand erosion, and the use of satellite data to measure these factors and their surrogates are discussed using the locational and control aspects of aeolian and litoral erosion zones along the sand beach of the Mississippi coast. The aeolian erosion is highlighted due to the redeposition of the sand which causes high cleanup costs, property damage, and safety and health hazards. The areas of differential erosion and the patterns of beach sand movement are illustrated and the use of remote sensing methods to identify the areas of erosion are evaluated.

1978-01-01

80

Device Oriented Project Controller  

SciTech Connect

This proposal is directed at the issue of developing control systems for very large HEP projects. A de-facto standard in accelerator control is the Experimental Physics and Industrial Control System (EPICS), which has been applied successfully to many physics projects. EPICS is a channel based system that requires that each channel of each device be configured and controlled. In Phase I, the feasibility of a device oriented extension to the distributed channel database was demonstrated by prototyping a device aware version of an EPICS I/O controller that functions with the current version of the channel access communication protocol. Extensions have been made to the grammar to define the database. Only a multi-stage position controller with limit switches was developed in the demonstration, but the grammar should support a full range of functional record types. In phase II, a full set of record types will be developed to support all existing record types, a set of process control functions for closed loop control, and support for experimental beam line control. A tool to configure these records will be developed. A communication protocol will be developed or extensions will be made to Channel Access to support introspection of components of a device. Performance bench marks will be made on both communication protocol and the database. After these records and performance tests are under way, a second of the grammar will be undertaken.

Dalesio, Leo; Kraimer, Martin

2013-11-20

81

76 FR 68745 - Notice of Intent To Update the Upland Erosion Control and Revegetation and Maintenance Plan and...  

Federal Register 2010, 2011, 2012, 2013

...Erosion Control and Revegetation and Maintenance Plan and the Wetland and Waterbody Construction and Mitigation Procedures and Request...Erosion Control, Revegetation and Maintenance Plan (Plan) and Wetland and Waterbody Construction and Mitigation Procedures...

2011-11-07

82

Does Rock Mass Strength Control the Rate of Alpine Cliff Erosion?  

NASA Astrophysics Data System (ADS)

Collapse of cliff faces by rockfall is a primary mode of bedrock erosion in alpine environments and plays a controlling role in mass removal from these systems. In this work we investigate the influence of rock mass strength on the retreat rate of alpine rock slopes. To quantify rockwall competence we employed the Slope Mass Rating (SMR) geomechanical strength index, which combines numerous factors that affect the strength of a rock mass, such as intact rock strength, joint frequency, joint condition, and more. The magnitude of cliff retreat was calculated by estimating the volume of talus at the toe of each rockwall and projecting that material back onto the cliff face, while accounting for the loss of production area as talus buries the base of the wall. Selecting sites within basins swept clean by advancing LGM glaciers allowed us to estimate the time period over which talus accumulation occurred (i.e. the production time). Dividing the magnitude of normal cliff retreat by the production time, we calculated erosion rates for each site. Our study area included a portion of the Sierra Nevada from Yosemite National Park in the south to Lake Tahoe in the north. Rockwall recession rates determined for 40 alpine cliffs in this region varied from 0.02 to 1.22 mm/year, with an average value of 0.28 mm/year. We found good correlation between rockwall recession rate and SMR that is best characterized by an exponential decrease in erosion rate with increasing rock mass strength. Analysis of the individual components of the SMR reveals that joint orientation (with respect to the cliff face) is the most important parameter affecting the rockwall erosion rate. The complete SMR score, however, best synthesizes the lithologic variables that contribute to the strength and erodibility of these rock slopes. Our data reveal no strong independent correlation between the measured rockwall retreat rate and environmental attributes (such as site elevation, aspect, cliff slope length, and cliff slope angle), suggesting that rock mass strength is the dominant parameter controlling the rate of cliff erosion in our study area.

Moore, J. R.; Sanders, J. W.; Dietrich, W. E.; Glaser, S. D.

2007-12-01

83

This project studied the effects of urbanization on flooding and erosion of small streams in the District of Columbia. The Hickey Run, which covers 1075 acres (435 ha)  

E-print Network

of the streams at present and in the future 2. soil erosion from the land and the stream channel erosion now was used in computing runoff hydrographs and peak discharges. For land erosion, the universal soil loss#12;ABSTRACT This project studied the effects of urbanization on flooding and erosion of small

District of Columbia, University of the

84

Bedload transport controls intra-event bedrock erosion  

NASA Astrophysics Data System (ADS)

Fluvial bedrock incision constrains the pace of mountainous landscape evolution. Fluvial erosion processes have been described with incision models that are widely applied in river reach and catchment scale studies. However, so far, no linked field data set at the process scale had been published that allows to assess model requirements and adequacy. Here, we evaluate the predictive power of various incision models on data on hydraulics, bedload transport and erosion recorded on an artificial bedrock slab installed in a steep mountain stream for a single bedload transport event. The influence of transported bedload on erosion rate (the "tools effect") is shown to be dominant while other effects are of minor importance. Hence, a simple temporal distributed incision model in which erosion rate is proportional to bedload transport rate is proposed for transient local studies. This model can be site-calibrated with temporally lumped bedload and erosion data and its applicability can be assessed by visual inspection of the study site. Basic discharge-based models like derivatives of the stream power model family however, are adequate to reproduce the overall trend of the observed erosion rate, at least for the event on hand. This is relevant for long-term studies of e.g. landscape evolution with no interest in transient local behaviour.

Beer, A. R.; Turowski, J. M.

2015-01-01

85

THE SOUTHWEST WASHINGTON COASTAL EROSION STUDY: A SCIENTIFIC RESEARCH PROJECT TO ADDRESS MANAGEMENT-SCALE OBJECTIVES  

Microsoft Academic Search

The Southwest Washington Coastal Erosion Study is a five-year, multi-disciplinary research project designed to build a knowledge foundation as a sound basis for addressing coastal management objectives. The purpose of the Study is to gain an understanding of a regional coastal sediment system, the Columbia River littoral cell, in order to support local, state, and federal decision-making in land-use planning,

George M. Kaminsky; Guy Gelfenbaum

86

Gullying and erosion control 507 Copyright 2006 John Wiley & Sons, Ltd. Earth Surf. Process. Landforms 31, 507525 (2006)  

E-print Network

Gullying and erosion control 507 Copyright © 2006 John Wiley & Sons, Ltd. Earth Surf. Process Gullying and erosion control at archaeological sites in Grand Canyon, Arizona Joel L. Pederson1 *, Paul A, USA Abstract Gully erosion of cultural sites in Grand Canyon National Park is an urgent management

Pederson, Joel L.

87

Erosion Basics  

NSDL National Science Digital Library

This homepage of Dr. Richard A. McLaughlin at North Carolina State University includes a four-part tutorial about soil erosion and mitigation. Slide presentations include an introduction to the factors that lead to soil erosion, a general discussion of soil characteristics and susceptibility to erosion, an overview of the formation of rills and gullies, and some examples of sediment transport dynamics and erosion reduction techniques. The site also features short videos that show tests of erosion control methods in an artificial environment.

Mclaughlin, Richard A.; University, North C.

88

Effect of nonerodible grains on wind erosion control  

Microsoft Academic Search

A simple drag partition scheme for rough surfaces of various roughness densities is presented to explain the effect of roughness density on apparent threshold friction velocity, the validity of which is confirmed by comparison with measured data sets. Based on this drag partition scheme, we assume that the presence of nonerodible rough grains affects the wind erosion of an erodible

Qingsong Mu

2010-01-01

89

Shoreline erosion control using marsh vegetation and low-cost structures  

SciTech Connect

Erosion is a serious threat to waterfront property along most of North Carolina's extensive estuarine shoreline. It is accelerated by man's intensive use and mismanagement. As demand for shoreline property increases -- for homesites, recreational areas, marinas and industrial sites -- its value increases, and landowners become more concerned about loss of land to erosion. There is a variety of erosion-control methods -- some beneficial, some useless and others that are even detrimental. Structural methods such as bulkheads, groins, revetments and riprap are often effective. But they are expensive to build and maintain and may have adverse environmental effects. Establishing vegetation is much cheaper than structural methods of erosion control, and the new marsh provides habitat, food and nutrients for organisms in the surrounding estuarine waters.

Broome, S.W.; Rogers, S.M.; Seneca, E.D.; Burgess, C.B.

1992-01-01

90

Cover crops effectiveness for soil erosion control in Sicilian vineyard  

NASA Astrophysics Data System (ADS)

In vineyards, which are very common in Mediterranean area, cover crops are becoming increasingly used to reduce soil erosion. Cover crops reduce runoff by increasing infiltration and increasing roughness and then reducing the ovelandflow velocity. The aim of the present study was to quantify soil and water losses under different soil managements systems on vineyards. The study site was a Sauvignon blanc winegrape vineyard located in Southwestern Sicily. Vineyards were managed both traditionally (conventional tillage) and alternative management using cover crops: 1) Vicia faba ; 2) Vicia faba and Vicia sativa; 3) Trifolium subterraneum, Lolium perenne, Festuca rubra; 4)Trifolium subterraneum, Festuca rubra and Festuca ovina, 5) Triticum durum, 6) Triticum durum and Vicia sativa. To monitor water and sediment yield, a Gerlach trough was installed at each treatment on the vineyard inter-row, with the row vineyard used as a border (topographical border). Runoff was measured after each rainfall event (raingauge 0.2 mm accuracy) from November 2005 to April 2007. And sediments were measured after desiccation. The results show that runoff and erosion were reduced considerably under the treatments with Trifolium subterraneum, Lolium perenne, Festuca rubra and Trifolium subterraneum, Festuca rubra and Festuca ovina (treatments 3 and 4). The soil losses were reduced by 73% under treatment 4 compared to the tillage plot. Conventional tillage and alternative management using Vicia faba cover crop (treatment 1) result the most ineffective treatment to soil erosion. These results show that the use of a cover crop can be a simple soil and water conservation practice in Sicilian vineyards. Key words: soil erosion, cover crops, vineyard, Mediterranean area.

Gristina, L.; Novara, A.; Saladino, S.; Santoro, A.

2009-04-01

91

Can anti-erosion dentifrices also provide effective plaque control?  

PubMed Central

Objective: While gingivitis and caries continue to be prevalent issues, there is growing concern about dental erosion induced by dietary acids. An oral hygiene product that protects against all these conditions would be beneficial. This study investigated the potential of two anti-erosion dentifrices to inhibit plaque. Methods: This was a randomized, three-period, two-treatment, double-blind, crossover study evaluating a stannous chloride/sodium fluoride dentifrice (SnCl2/NaF, blend-a-med® Pro Expert) and a popular anti-erosion dentifrice (NaF, Sensodyne® ProNamel™). During Period 3, subjects were randomized to repeat one treatment to evaluate any product carryover effects. Each treatment period was 17 days. Test dentifrices were used with a standard manual toothbrush. Digital plaque image analysis (DPIA) was employed at the end of each period to evaluate plaque levels (i) overnight (am prebrush); (ii) post-brushing with the test product (am post-brush); and (iii) mid-afternoon (pm). Analysis was conducted via an objective computer algorithm, which calculated total area of visible plaque. Results: Twenty-seven subjects completed the study. At all time points, subjects had statistically significantly (P ? 0.0001) lower plaque levels after using the SnCl2/NaF dentifrice than the NaF dentifrice. The antiplaque benefit for the SnCl2/NaF dentifrice versus the NaF dentifrice was: am prebrush = 26.0%; am post-brushing = 27.9%; pm = 25.7%. Conclusions: The SnCl2/NaF dentifrice provided significantly greater daytime and overnight plaque inhibition than the NaF toothpaste. When recommending dentifrice to patients susceptible to dental erosion, clinicians can consider one that also inhibits plaque. PMID:21356021

Bellamy, PG; Prendergast, M; Strand, R; Yu, Z; Day, TN; Barker, ML; Mussett, AJ

2011-01-01

92

PUBLISHED ONLINE: 28 FEBRUARY 2010 | DOI: 10.1038/NGEO776 Landslide erosion controlled by hillslope material  

E-print Network

LETTERS PUBLISHED ONLINE: 28 FEBRUARY 2010 | DOI: 10.1038/NGEO776 Landslide erosion controlled belts are eroded by landslides, and landsliding is ultimately driven by the topographic relief produced by fluvial and glacial erosion1­5 . Landslide erosion rates are derived from estimates of landslide volume

Montgomery, David R.

93

Wind tunnel experimental study on the effect of PAM on soil wind erosion control  

Microsoft Academic Search

In recent years, high-molecular-weight anionic polyacrylamide (PAM) have been widely tested on a variety of soils, primarily\\u000a in water erosion control. However, little information is available regarding the effectiveness of PAM on preventing soil loss\\u000a from wind erosion. The research adopted room wind tunnel experiment, two kinds of soils were used which were from the agro-pastoral\\u000a area of Inner Mongolia,

Ji-Jun He; Qiang-Guo Cai; Ze-Jun Tang

2008-01-01

94

The Use of Submerged Narrow-Crested Breakwaters for Shoreline Erosion Control  

Microsoft Academic Search

STAUBLE, D.K. and TABAR, J.R., 2003. The Use of Submerged Narrow-Crested Breakwaters for Shoreline Erosion Control. Journal of Coastal Research, 19(3), 684-722. West Palm Beach (Florida), ISSN 0749-0208. The performance of six installations of modular narrow-crested submerged breakwaters constructed of prefabricated concrete has been reviewed as a possible lower cost shoreline erosion prevention device. Two types of breakwaters that have

Donald K. Stauble; Jeffery R. Tabar

95

Reflectance loss of prospective solar concentrator mirrors in erosive environments. The Crosbyton Solar Power Project  

SciTech Connect

The problem addressed in this phase of the Crosbyton Solar Power Project was that of the effect of weathering of solar concentrator mirrors proposed for use in the fixed-mirror, distributed-focus (solar bowl) system with particular emphasis on erosion due to exposure during dust storms. The specific objectives of this research were to evaluate the mirrors with respect to initial reflectance, loss of reflectance due to dust storms and other outdoor exposure phenomena, and dimensional stability; and to develop a rapid technique for the simulation of dust storms so that a model for such reflectance loss as a function of exposure could be developed.

Bethea, R.M.; Barringer, M.T.; Chin, S.; Collier, E.G.; Cooper, A.M.; Reichert, J.D. Jr.; Williams, P.F.

1986-01-01

96

A field experiment on the controls of sediment transport on bedrock erosion  

NASA Astrophysics Data System (ADS)

The earth`s surface is naturally shaped by interactions of physical and chemical processes. In mountainous regions with steep topography river incision fundamentally controls the geomorphic evolution of the whole landscape. There, erosion of exposed bedrock sections by fluvial sediment transport is an important mechanism forming mountain river channels. The links between bedload transport and bedrock erosion has been firmly established using laboratory experiments. However, there are only few field datasets linking discharge, sediment transport, impact energy and erosion that can be used for process understanding and model evaluation. To fill this gap, a new measuring setup has been commissioned to raise an appropriate simultaneous dataset of hydraulics, sediment transport and bedrock erosion at high temporal and spatial resolution. Two natural stone slabs were installed flush with the streambed of the Erlenbach, a gauged stream in the Swiss Pre-Alps. They are mounted upon force sensors recording vertical pressure und downstream shear caused by passing sediment particles. The sediment transport rates can be assessed using geophone plates and an automated moving basket system taking short-term sediment samples. These devices are located directly downstream of the stone slabs. Bedrock erosion rates are measured continuously with erosion sensors at sub-millimeter accuracy at three points on each slab. In addition, the whole slab topography is surveyed with photogrammetry and a structured-light 3D scanner after individual flood events. Since the installation in 2011, slab bedrock erosion has been observed during several transport events. We discuss the relation between hydraulics, bedload transport, resulting pressure forces on the stone slabs and erosion rates. The aim of the study is the derivation of an empirical process law for fluvial bedrock erosion driven by moving sediment particles.

Beer, A. R.; Turowski, J. M.; Fritschi, B.; Rieke-Zapp, D.; Campana, L.; Lavé, J.

2012-12-01

97

Large-scale performance and design for construction activity erosion control best management practices.  

PubMed

The National Pollutant Discharge Elimination System (NPDES) Phase II requires construction activities to have erosion and sediment control best management practices (BMPs) designed and installed for site storm water management. Although BMPs are specified on storm water pollution prevention plans (SWPPPs) as part of the construction general permit (GP), there is little evidence in the research literature as to how BMPs perform or should be designed. The objectives of this study were to: (i) comparatively evaluate the performance of common construction activity erosion control BMPs under a standardized test method, (ii) evaluate the performance of compost erosion control blanket thickness, (iii) evaluate the performance of compost erosion control blankets (CECBs) on a variety of slope angles, and (iv) determine Universal Soil Loss Equation (USLE) cover management factors (C factors) for these BMPs to assist site designers and engineers. Twenty-three erosion control BMPs were evaluated using American Society of Testing and Materials (ASTM) D-6459, standard test method for determination of ECB performance in protecting hill slopes from rainfall induced erosion, on 4:1 (H:V), 3:1, and 2:1 slopes. Soil loss reduction for treatments exposed to 5 cm of rainfall on a 2:1 slope ranged from-7 to 99%. For rainfall exposure of 10 cm, treatment soil loss reduction ranged from 8 to 99%. The 2.5 and 5 cm CECBs significantly reduced erosion on slopes up to 2:1, while CECBs < 2.5 cm are not recommended on slopes >or= 4:1 when rainfall totals reach 5 cm. Based on the soil loss results, USLE C factors ranged from 0.01 to 0.9. These performance and design criteria should aid site planners and designers in decision-making processes. PMID:19398523

Faucette, L B; Scholl, B; Beighley, R E; Governo, J

2009-01-01

98

Extreme soil erosion rates in citrus slope plantations and control strategies. A literature review  

NASA Astrophysics Data System (ADS)

Soil Erosion is a natural process that shapes the Earth. Due to the impact of agriculture, soil erosion rates increase, landforms show gullies and rills, and soils are depleted. In the Mediterranean, wheat, olive and vineyards were the main agriculture products, but new plantations are being found in sloping terrain due to the drip-irrigation. This new strategy results in the removal of the traditional terraces in order to make suitable for mechanization the agriculture plantation. Citrus is a clear example of the impact of the new chemical agriculture with a high investment in herbicides, pesticides, mechanisation, land levelling and drip computer controlled irrigation systems. The new plantation of citrus orchards is found in the Mediterranean, but also in California, Florida, China and Brazil. Chile, Argentina, and South Africa are other producers that are moving to an industrial production of citrus. This paper shows how the citrus plantations are found as one of the most aggressive plantation due to the increase in soil erosion, and how we can apply successful control strategies. The research into the high erosion rates of citrus orchard built on the slopes are mainly found in China (Wu et al., 1997; Xu et al., 2010; Wang et al., 2011; Wu et al., 2011; Liu et al., 2011; Lü et al., 2011; Xu et al., 2012) and in the Mediterranean (Cerdà and Jurgensen, 2008; 2009; Cerdà et al., 2009a; 2009b; Cerdà et al., 2011; 2012) Most of the research done devoted to the measurements of the soil losses but also some research is done related to the soil properties (Lu et al., 1997; Lü et al., 2012; Xu et al., 2012) and the impact of cover crops to reduce the soil losses (Lavigne et al., 2012; Le Bellec et al., 2012) and the use of residues such as dried citrus peel in order to reduce the soil losses. There are 116 million tonnes of citrus produced yearly, and this affects a large surface of the best land. The citrus orchards are moving from flood irrigated to drip irrigated land, and this contributes to increase the soil losses due to the sloping terrain. Although citrus is a world wide food, and occupy a large surface little is being researched on their impact on soil erosion, land degradation and strategies to control the soil, water and nutrient losses. This paper review the research developed until now and the results show that there is a poor background on this topic. It is necessary to develop research projects to improve the knowledge on the impact of citrus plantations on soil degradation and soil erosion. Another key information from the literature review done, is that most of the research was done in two regions of China and one of the Mediterranean. Definitively, a poor understanding of a huge environmental problem that need more scientific research. Acknowledgements The research projects GL2008-02879/BTE and LEDDRA 243857 supported this research. References Bombino, G., Denisi, P., Fortugno, D., Tamburino, V., Zema, D.A., Zimbone, S.M. 2010. Land spreading of solar-dried citrus peel to control runoff and soil erosion. WIT Transactions on Ecology and the Environment, 140, 145-154. Cerdà, A., Giménez Morera, A., Burguet, M., Arcenegui, V., González Peñaloza, F.A., García-Orenes, F., Pereira, P. 2012. The impact of the farming, abandonment and agricultural intensification on loss of water and soil. The example of the northern slopes of the Serra Grossa, Eastern Spain [El impacto del cultivo, el abandono y la intensificación de la agricultura en la pérdida de agua y suelo. el ejemplo de la vertiente norte de la serra grossa en el este peninsular] Cuadernos de Investigacion Geografica, 38 (1), 75-94. Cerdà, A., Jurgensen, M.F. 2008. The influence of ants on soil and water losses from an orange orchard in eastern Spain. Journal of Applied Entomology, 132 (4), 306-314. Cerdà, A., Jurgensen, M.F. 2011. Ant mounds as a source of sediment on citrus orchard plantations in eastern Spain. A three-scale rainfall simulation approach. Catena, 85 (3), 231-236. Cerdà, A., Jurgensen, M.F., Bodi, M.B. 2009. Effects of ants on

Cerdà, Artemi; Ángel González Peñaloza, Félix; Pereira, Paulo; Reyes Ruiz Gallardo, José; García Orenes, Fuensanta; Burguet, María

2013-04-01

99

EFFECTS OF WOODY DEBRIS EROSION CONTROL STRUCTURES ON FISH COMMUNITIES OF LITTLE TOPASHAW CREEK, MS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fish were sampled by backpack electroshocker from Little Topashaw Creek, MS to evaluate the effectiveness of bank stabilization structures constructed of large woody debris in reducing erosion and improving aquatic habitat. Specific details of project design and of physical habitat and morphology o...

100

Environmental evaluation of flue gas desulfurization gypsum as a BMP for erosion control  

Technology Transfer Automated Retrieval System (TEKTRAN)

Flue Gas Desulfurization Gypsum (FGDG) is produced from pollution control systems reducing sulfur dioxide emissions from thermo-electric coal-fired power plants. Natural gypsum and FGDG both have been shown to be useful in control of soil erosion. However, concerns have been raised recently by envir...

101

Controls on slope-wash erosion rates in the Mojave Desert  

NASA Astrophysics Data System (ADS)

This study estimates the rates of soil erosion by slope wash in an arid region and the various factors that control these rates. Decadal-scale erosion rates were estimated on hillslope scales using inventories of 137Cs that were sampled from 46 soil profiles in four different study sites in the Mojave Desert. Calculated mean soil erosion rates per site range from -3.6 to -24.3 t ha-1 yr-1. Higher mean rates were associated with gently sloping sites that exhibit low percentage of rock and vegetation coverage, whereas lower mean rates corresponded to steep and rocky sites. Individual erosion rates were not correlated to slope gradient or curvature but were negatively correlated with the volume fraction of rocks in the upper soil profile (i.e., upslope rock coverage). Since the slopes get rockier as they get steeper, any increase in erosion rates with increasing slope is outweighed by the inhibiting effect of greater rock cover. This, together with sandy-loam soil texture on the steep slopes hinders runoff and erosion. Our findings are supported by soil data that show greater heterogeneity in the degree of calcic soil development and higher soluble salt contents in more gently sloping sites that are characterized by high erosion rates. The erosion rates reported here for the gently sloping sites are higher than rates calculated for semi-arid regions, probably due to the lower rock and vegetation coverage in these sites compared to wetter areas. These rates are also higher than millennial-scale rates estimated for the Mojave Desert on watershed scales, and suggest that at least part of the eroded sediments are stored in the adjacent streams and do not reach the piedmonts.

Crouvi, O.; Polyakov, V. O.; Pelletier, J. D.; Rasmussen, C.

2014-06-01

102

Erosion risk assessment of controlled burning of grasses established on steep slopes  

NASA Astrophysics Data System (ADS)

It is a standard practice to establish grasses on steep slopes (batters) of embankments and cuttings to minimise erosion problems. However, the increase in grass density (high biomass) on the steep slopes poses a greater risk of fire. Controlled burning is a common fuel hazard reduction program employed to minimise the fire risks. The increased risk of erosion on the steep slopes after controlled burning has received little attention if any. This paper assesses the erosion risks associated with controlled burning of grasses established on steep slopes. Grasses, with and without the aid of waste ballast rock mulch, were established on 10 m wide railway embankment batter experiment plots. Two-and-a-half years after the grass establishment, selected plots were controlled burned. Runoff and soil loss from the experimental plots were monitored throughout the 3½-year period of the experiment. After one year the grass cover on the burned plots has hardly exceeded 60%, far below the average pre-burn levels of about 80%. All treatments achieved an incredible soil loss reduction of over 95% (compared with the bare scenario) without controlled burning at the end of the 3½-year period. This percentage value was decreased numerically by 14 where controlled burning was implemented. Compared with the 100% grass cover treatment, runoff rates tripled while erosion rates increased by nine-fold for the waste ballast treatment, and 17-fold for the non-waste ballast treatment, during the first year following controlled burning.

Gyasi-Agyei, Yeboah

2006-02-01

103

TRUCKEE MEADOWS FLOOD CONTROL PROJECT,  

E-print Network

the Pre- construction Engineering and Design (PED) phase when changes in real estate costs madeTRUCKEE MEADOWS FLOOD CONTROL PROJECT, NEVADA DRAFT GENERAL REEVALUATION REPORT May 2013 #12;#12;Truckee Meadows Flood Control Project, Nevada Draft General Reevaluation Report May 2013 Prepared by U

US Army Corps of Engineers

104

Erosion control on a steeply sloped pipeline right-of-way in southwestern Pennsylvania  

SciTech Connect

The results of precipitation on steeply sloped pipeline rights-of-way (ROWs) during the time between ROW rehabilitation and the establishment of a dense, self-sustaining vegetative ground cover can cause locally severe soil erosion. This erosion results in elevated sediment loads in receiving streams and increases the difficulty and costs of ROW maintenance. A field study was completed that compared the environmental effectiveness of nine treatments on a 28% ROW slope in southwestern Pennsylvania. The six erosion-control methods investigated in the study, selected to represent a wide range in material type and installation cost, were (1) heavy application of straw mulch, (2) light application of straw mulch, (3) processed wood fiber, (4) chemical soil binder, (5) paper strips in netting, and (6) light straw mulch with a tacking agent. Each of the test plots also received the basic treatment of limestone, fertilizer, and a seed mixture commonly used to rehabilitate ROWs in the region. Precipitation, runoff volumes, and sediment yields were measured on each of 51 plots for 45 precipitation events during the 18-month study. Vegetation data were collected by the point-intercept method four times during the study to determine the amount of plant cover and species composition. Differences in sediment yield were observed among methods and between ROW location, but plant cover development was not influenced by erosion-control method or location. The relationship between environmental and cost data indicated that, of the six erosion-control methods tested, a light application of straw mulch was the most effective erosion-control treatment. 19 refs., 2 figs., 6 tabs.

Zellmer, S.D.; Edgar, D.E. (Argonne National Lab., IL (USA)); Isaacson, H.R. (Gas Research Inst., Chicago, IL (USA))

1991-01-01

105

Erosion control practices integrated with polyacrylamide for nutrient reduction in rill irrigation runoff  

Microsoft Academic Search

The objective of this research was to assess soil conservation practices for improving water quality of return flows from rill irrigation in the Yakima River Basin, Washington, by combining patch application of polyacrylamide (PAM) with an additional erosion control practice. A 2-year field study was conducted that combined PAM with (1) check dams, (2) surge irrigation, (3) surface drains, and

A. A. Szögi; B. G. Leib; C. A. Redulla; R. G. Stevens; G. R. Mathews; D. A. Strausz

2007-01-01

106

Comprehensive Erosion and Sediment Control Training Program for Job Superintendents and Inspectors.  

ERIC Educational Resources Information Center

One of two training program texts built around the Virginia Erosion and Sediment Control Law and Program, this guide presents a program designed to meet the needs of job superintendents and inspectors. (The other guide, containing a program for engineers, architects, and planners, was designed to train professional people who need engineering and…

Porter, Harry L., Jr.

107

Comprehensive Erosion and Sediment Control Training Program for Engineers, Architects and Planners.  

ERIC Educational Resources Information Center

This program training text was designed to provide uniform instruction to the engineer, architect, planner, and others who will be helping to implement an erosion and sediment control program. Although tailored for use in Virginia, the basic principles covered are universal, and the material is adaptable to meet the needs in any State. The 11…

Porter, Harry L., Jr.

108

Soil erosion and sediment control laws. A review of state laws and their natural resource data requirements  

NASA Technical Reports Server (NTRS)

Twenty states, the District of Columbia, and the Virgin Islands enacted erosion and sediment control legislation during the past decade to provide for the implementation or the strengthening of statewide erosion and sediment control plans for rural and/or urban lands. That legislation and the state programs developed to implement these laws are quoted and reviewed. The natural resource data requirements of each program are also extracted. The legislation includes amendments to conservation district laws, water quality laws, and erosion and sediment control laws. Laws which provides for legislative review of administrative regulations and LANDSAT applications and/or information systems that were involved in implementing or gathering data for a specific soil erosion and sediment control program are summarized as well as principal concerns affecting erosion and sediment control laws.

Klein, S. B.

1980-01-01

109

Project EARTH-12-PPS1: Weathering Rates in the Critical Zone: Soil Erosion, River Chemistry and Climate  

E-print Network

Project EARTH-12-PPS1: Weathering Rates in the Critical Zone: Soil Erosion, River Chemistry and Climate Change Supervisors: Dr. Philip Pogge von Strandmann and Prof. Gideon Henderson Chemical weathering weathering has also been proposed as a geo-engineering method to sequester carbon. It has therefore become

Henderson, Gideon

110

Controls of initial topography on temporal and spatial patterns of glacial erosion  

NASA Astrophysics Data System (ADS)

Here we investigate the influence of initial pre-glacial topography on spatial and temporal patterns of glacial erosion using numerical surface process modelling, including a higher order ice sheet model. First, we consider glacier dynamics when simulating glaciation in two real landscapes, representing plateau-type topography (southeast Australia) and characteristic steady-state fluvial topography (southern Taiwan). We find that the different initial landscape configurations result in distinctly different ice configurations and patterns of basal sliding. The sliding patterns are controlled by ice configuration and the resulting basal shear stresses and by the thermal properties at the base of the ice. We then investigate how these characteristic patterns of basal sliding control glacial erosion and long-term landscape evolution using synthetic representations of the two landscapes. The two landscape configurations result in markedly different spatial and temporal patterns of glacial erosion. However, the resulting landscapes may have similar morphology, irrespective of initial landscapes and glacial erosion patterns being significantly different. The numerical experiments also suggest that, in addition to basal temperature, basal shear stress is important in restricting long-term glacial erosion, which is relevant for the preservation of landforms during glaciations. Specifically, pre-glacial landforms may be eroded although they are initially protected by cold-based ice, when the ice configuration promotes significant basal shear stress (glacial erosion) at the edge of a plateau-like landscape. In contrast, pre-glacial landforms may be preserved irrespective of the ice being warm-based, when low gradients in the ice surface act to limit basal shear stress.

Pedersen, Vivi K.; Huismans, Ritske S.; Herman, Frédéric; Egholm, David L.

2014-10-01

111

Offshore sand resources for coastal erosion control in Louisiana  

Microsoft Academic Search

An inventory of existing geophysical data supplemented by more than 15,000 km of high-resolution seismic profiles and 400 vibracores collected cooperatively by the Louisiana Geological Survey and US Geological Survey since 1981 indicates that a wide range of aggregate minerals occurs on the continental shelf in a variety of depositional settings. The distribution of these deposits is controlled by the

K. E. Ramsey; S. Penland; R. A. McBride; J. R. Suter; J. Williams

1990-01-01

112

Project resources planning and control  

NASA Technical Reports Server (NTRS)

This report contains instructional guidelines for the resources planning and control of research and development (R&D) projects managed by NASA's Langley Research Center (LaRC). Although written to serve primarily as a practical guide and reference for those LaRC personnel who perform resources planning, analysis, control, and reporting functions, it should also be meaningful to other NASA personnel who are directly or indirectly involved in or affected by these functions, especially project technical managers whose responsibilities include resources management. Certain sections should help Contractor personnel to better understand what resources information must usually be submitted on LaRC projects and what use is made of such information. The Project Manager of a large R&D project typicaly receives support from an Analyst in the area of resources management. The Analyst provides assistance in four functional areas: Planning, Analysis/Control, Administration, and Reporting. Each of these functions are discussed in detail. Examples of techniques used effectively on LaRC projects have been included where applicable. A considerable amount of information has been included on the use of Performance Measurement (Earned Value) Systems for contract cost control and reporting as little information is currently available on this subject in NASA publications.

Sibbers, C. W.

1984-01-01

113

INNOVATIVE IN-SITU REMEDIATION OF CONTAMINATED SEDIMENTS FOR SIMULTANEOUS CONTROL OF CONTAMINATION AND EROSION  

SciTech Connect

New technologies are needed that neutralize contaminant toxicity and control physical transport mechanisms that mobilize sediment contaminants. The last 12 months of this comprehensive project investigated the use of combinations of sequestering agents to develop in situ active sediment caps that stabilize mixtures of contaminants and act as a barrier to mechanical disturbance under a broad range of environmental conditions. Efforts focused on the selection of effective sequestering agents for use in active caps, the composition of active caps, and the effects of active cap components on contaminant bioavailability and retention. Results from this project showed that phosphate amendments, some organoclays, and the biopolymer, chitosan, were very effective at removing metals from both fresh and salt water. These amendments also exhibited high retention (80% or more) of most metals indicating reduced potential for remobilization to the water column. Experiments on metal speciation and retention in contaminated sediment showed that apatite and organoclay can immobilize a broad range of metals under both reduced and oxidized conditions. These studies were followed by sequential extractions to evaluate the bioavailability and retention of metals in treated sediments. Metal fractions recovered in early extraction steps are more likely to be bioavailable and were termed the Potentially Mobile Fraction (PMF). Less bioavailable fractions collected in later extraction steps were termed the Recalcitrant Factor (RF). Apatite and organoclay reduced the PMF and increased the RF for several elements, especially Pb, Zn, Ni, Cr, and Cd. Empirically determined partitioning coefficients and modeling studies were used to assess the retention of organic contaminants on selected sequestering agents. Organoclays exhibited exceptionally high sorption of polycyclic aromatic hydrocarbons as indicated by a comparison of K{sub d} values among 12 amendments. These results suggested that organoclays have high potential for controlling organic contaminants. Measured partitioning coefficients were used to model the time required for a contaminant to penetrate sediment caps composed of organoclay. The results showed that a thin layer of highly sorptive organoclay can lead to very long migration times, perhaps longer than the expected lifetime of the contaminant in the sediment environment. A one-dimensional numerical model was used to examine the diffusion of metals through several cap material based on measured and assumed material and transport properties. These studies showed that active caps composed of apatite or organoclay have the potential to delay contaminant breakthrough due to diffusion by hundreds of years or more compared with passive caps composed of sand. Advectively dominated column experiments are currently underway to define effective sorption related retardation factors in promising amendments for various hydrophobic organic compounds. Upon completion of these experiments, advection transient models will be used to estimate the time required for the breakthrough of various contaminants in caps composed of different experimental materials. Biopolymer products for inclusion in active caps were evaluated on the basis of resistance to biodegradation, sorption capacity for organic and inorganic contaminants, and potential for erosion control. More than 20 biopolymer products were evaluated resulting in the selection of chitosan/guar gum cross-linked with borax and xanthan/chitosan cross-linked with calcium chloride for inclusion in active caps to produce a barrier that resists mechanical disturbance. A process was developed for coating sand with cross-linked biopolymers to provide a means for delivery to the sediment surface. Properties of biopolymer coated sand such as carbon fraction (indicating biopolymer coverage), porosity, bulk density, and biodegradability have been evaluated, and experiments are currently underway to assess the resistance of biopolymer coated sand to erosion. Although the ability of active cap materials to remediat

Knox, A; Michael Paller, M; Danny D. Reible, D; Ioana G. Petrisor, I

2007-11-28

114

Runoff prediction from sagebrush rangelands using water erosion prediction project (WEPP)  

Microsoft Academic Search

Abstract Runoff prediction is an important component,of any process- based soil erosion model. In this paper we evaluate the runoff prediction capabilities of a new soil erosion model, WEPP, on sagebrush rangelands. Particular attentton was,given to the parameter estimation techniques used in WEPP to predict htfiltra- tion. Runoff volume predicted by WEPP is based on the Green and Ampt infiltration

Bradford P. Wilcox; Mina Sbaa; Wilbert H. Blackburn; H James

115

Assessment of the role of bottomland hardwoods in sediment and erosion control  

USGS Publications Warehouse

Drainage and clearing of bottomland hardwoods have long been recognized by the U.S. Environmental Protection Agency (EPA) and the U.S. Fish and Wildlife Service (Service) as important impacts of Federal water projects in the lower Mississippi River Valley. More recently, the water quality impacts of such projects (e.g., increases in sediments, nutrients, and pesticides) have also become of concern. In 1984, in an effort to better define problems concerning wetland losses and water degradation, EPA initiated a cooperative project with the Western Energy and Land Use Team (now the National Ecology Research Center) of the Service. Three phases of the project were identified: 1. To collect existing literature and data; 2. To select, develop, and test the utility of methods to quantify the relationships between land use, cover types, soils, hydrology, and water quality (as represented by sediment); and 3. To apply selected methodologies to several sites within the Yazoo Basin of Mississippi to determine the, potential effectiveness of various management alternatives to reduce sediment yield, increase sediment deposition, and improve water quality. Methods development focused on linking a simulation of water and sediment movement to a computerized geographic information system. We had several objectives for the resulting model. We desired that it should: 1. Estimate the importance of bottomland and hardwoods as a cover type that performs the functions of erosion and sediment control, 2. Simulate effects of proportions of ' various cover types and their specific spatial configurations, 3. Be applicable to moderately large spatial areas with minimal site-specific calibration, 4. Simulate spatial patterns of sediment loss-gain over time, and 5. Represent both sediment detachment and transport. While it was recognized that impacts and management alternatives could be sorted roughly into landscape measures and channel measures, the decision was made to focus study efforts mainly on landscape measures. Landscape measures include altered drainage and flooding patterns, altered cover types (e.g., conversion of bottomland hardwoods to agricultural crops, reforestation of cropland to bottomland hardwoods, and creation of riparian buffer strips), altered cropping and tillage patterns, altered routing of water, and creation of buffer strips along wetlands and channel margins. Channel measures include vegetative bank stabilization, grade control structures, and regulation of channel water volume and velocity. During the first year of the study, EPA decided not to fund the third phase of the project. This required considerable rescoping of the project with the result that application of the sediment mobilization, routing, and deposition models to various management alternatives and portions of the Yazoo Basin was somewhat restricted. We believe, however, that this report will provide a good understanding of the various modes of sediment mobilization, transport, and deposition within the Yazoo Basin, as well as of the role of bottomland hardwoods. The model developed in this study could be applied to a variety of management or mitigation alternatives prior to implementation to determine their relative effectiveness. Policy, political, and socio-economic consequences of any proposed management/mitigation practice, however, must ultimately be taken into consideration by those charged with management of water resources within the Yazoo Basin before any practice is implemented. This study makes no effort to judge the feasibility of management alternatives in this regard.

Molinas, A.; Auble, Gregor T.; Segelquist, C.A.; Ischinger, Lee S.

1988-01-01

116

Project test plan for runoff and erosion on fine-soil barrier surfaces and rock-covered side slopes  

SciTech Connect

Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company are working together to develop protective barriers to isolate near-surface radioactive waste. The purpose of the barriers is to protect defense wastes at the US Department of Energy's (DOE) Hanford Site from infiltration of precipitation, biointrusion, and surficial erosion for up to 10,000 years without the need for long-term monitoring, maintenance, or institutional control. The barriers will be constructed of layered earth and rock material designed to direct surface and groundwater pathways away from the buried waste. To address soil erosion as it applies to barrier design and long-term stability, a task designed to study this problem has been included in the Protective Barriers Program at PNL. The barrier soil-erosion task will investigate the ability of the soil cover and side slopes to resist the erosional and destabilizing processes from externally applied water. The study will include identification and field testing of the dominant processes contributing to erosion and barrier failure. The effects of rock mulches, vegetation cover on the top fine-grained soil surface, as well as the stability of rock armoring on the side slopes, will be evaluated. Some of the testing will include the effects of animal intrusion on barrier erosion, and these will be coordinated with other animal intrusion studies. 6 refs., 4 figs., 1 tab.

Walters, W.H.; Hoover, K.A.; Cadwell, L.L.

1990-06-01

117

[Mechanisms of grass in slope erosion control in Loess sandy soil region of Northwest China].  

PubMed

By adopting the method of simulated precipitation and from the viewpoint of slope hydrodynamics, in combining with the analysis of soil resistance to erosion, a quantitative study was made on the mechanisms of grass in controlling the slope erosion in the cross area of wind-water erosion in Loess Plateau of Northwest China under different combinations of rainfall intensity and slope gradient, aimed to provide basis to reveal the mechanisms of vegetation in controlling soil erosion and to select appropriate vegetation for the soil and water conservation in Loess Plateau. The grass Astragalus adsurgens with the coverage about 40% could effectively control the slope erosion. This grass had an efficiency of more than 70% in reducing sediment, and the grass root had a greater effect than grass canopy. On bare slope and on the slopes with the grass plant or only the grass root playing effect, there existed a functional relation between the flow velocity on the slopes and the rainfall intensity and slope gradient (V = DJ(0.33 i 0.5), where V is flow velocity, D is the comprehensive coefficient which varies with different underlying surfaces, i is rainfall intensity, and J is slope gradient). Both the grass root and the grass canopy could markedly decrease the flow velocity on the slopes, and increase the slope resistance, but the effect of grass root in decreasing flow velocity was greater while the effect in increasing resistance was smaller than that of grass canopy. The effect of grass root in increasing slope resistance was mainly achieved by increasing the sediment grain resistance, while the effect of canopy was mainly achieved by increasing the slope form resistance and wave resistance. The evaluation of the soil resistance to erosion by using a conceptual model of sediment generation by overland flow indicated that the critical shear stress value of bare slope and of the slopes with the grass plant or only the grass root playing effect was 0.533, 1.672 and 0.925 Pa, respectively. PMID:23717998

Zhao, Chun-Hong; Gao, Jian-En; Xu, Zhen

2013-01-01

118

Microphonics control for Project X  

SciTech Connect

The proposed multi-MW Project X facility at Fermilab will employ cavities with bandwidths as narrow as 20 Hz. This combination of high RF power with narrow bandwidths combined requires careful attention to detuning control if these cavities are to be operated successfully. Detuning control for Projects X will require a coordinated effort between the groups responsible for various machine subsystems. Considerable progress in this area has been made over the past year. Detuning levels in the Project X cavities, specifically the Low and High {beta} 650 MHz elliptical types, can have a significant impact on the overall cost of the project. The narrow bandwidths, and the high RF Power requirements, and the large number of these cavities mean that careful attention to detuning control will be required if these cavities are to operate successfully. Limiting cavity detuning in Project X will require a coordinated effort between the groups responsible for various subsystems of the planned machine. Considerable progress towards this goal has been made by each of these groups over the past year.

Schappert, W.; Barbanotti, S.; Branlard, J.; Cancelo, G.; Carcagno, R.; Chase, B.; Champion, M.; Gonin, I.; Klebaner, A.; Orris, D.; Pischalnikov, Y.; /Fermilab

2011-03-01

119

Biodiversity in riverbank techniques for erosion control: assessment of animal and plant species diversity along a natural gradient.  

E-print Network

Biodiversity in riverbank techniques for erosion control: assessment of animal and plant species * Corresponding author: paul.cavaille@cemagref.fr Keywords: beetles, biodiversity, ecological restoration, plant.). However, whether such installations can accommodate natural biodiversity has not been well assessed

Paris-Sud XI, Université de

120

Fluor Fernald - Project Controls Process  

SciTech Connect

This paper will look at the project controls process Fluor has developed to ensure cleanup can be declared and verified by the contract in the shortest time possible. In November 2000 the Department of Energy and Fluor Fernald entered into a closure contract that incentivized Fluor Fernald to reduce the cost and schedule of the cleanup. Original schedule estimates to complete the job went well beyond 2010. In 2002 the Department of Energy (DOE) renegotiated the contract with emphasis on completing the cleanup by December 2006. This model for site closure was developed and has worked effectively to move the project through the cleanup phase, to change a culture and set in motion the steps necessary to declare closure and ultimately leave the project in a timely manner. It is Fluor's goal to complete the project safely, ahead of schedule and cost estimates thereby maximizing profit for company shareholders. This paper will demonstrate the successful implementation for an integrated project management system that has been proven and used on the Fluor Fernald project. The objective is to summarize the approach used at Fernald in setting forth those management processes to accelerate schedule and reduce cost while managing the project safely. (authors)

Reed, C.W. [Fluor Fernald, Inc., P.O. Box 538704, Cincinnati, OH 45253 (United States)

2006-07-01

121

Vegetation cover plays the most important role in soil erosion control.  

PubMed

To obtain, characteristics and behaviors of soil erosion phenomena, to control it's harms and reduce it's risks, realistic data from soil erosion rates are necessary. Mean while, measuring soil erosion rates particularly in large scale is a time consuming and expensive task. Moreover, spatial and temporal changes of soil erosion increase this problem. Therefore, to find out a certain way of creating capable methods which easily and quickly be able to estimate soil erosion rate, is quite logical. So, different models are widely used, but, may be the most important consideration with this regard is that, these models should be previously, tested and adopted to defined areas to stop probability of causing some huge and meaningful errors. Therefore, to achieve the above mentioned aim, different methods are used. Anyway, conditions which resulted to create a suitable model, should be considered in a defined area where, model is applied, unless, model application can leads to huge risks. This study is an attempt with this refer, that is, with comparing measured soil loss rates and predicted soil erosion rates from a defined catchment area, created a reasonable relationship between them and achieved the main aim of the study. That is, one of the small upland catchments of Emam kandi of Urmia with 75 ha area which is part of the Urmia lake catchment area and under layned by calcareous parent material, is selected as a study site. Selected catchment has natural pasture and has closured during the recent years. To calculate sediment yield the following processes were done: first, estimating the volume of trapped sediments, then, surveying the catchment area, for calculating sediment yield. Measured sediment yield is 6.19 t ha(-1) year(-1) which leads to soil loss rate of 13.76 t ha(-1) year(-1) by using Sediment Delivery Ratio (SDR). Also, inside the measurement of sediment yields and calculation of soil loss rates, two models of MUSLE and PSIAC were used respectively after exclosure and before exclosure to predict soil loss rates. Predicted soil loss rates by MUSLE and PSIAC respectively are 12.80 and 26.5 t ha(-1) year(-1). Finally, Comparisons and statistical analysis and scientific discussions were made. PMID:19069506

Mahmoudzadeh, A

2007-02-01

122

Beach Erosion  

NSDL National Science Digital Library

The Beach Erosion site of the WhyFiles (last mentioned in the August 9, 1996 Scout Report), a project funded by the graduate school of the University of Wisconsin-Madison, has been recently updated. Its newest addition includes a story about the population of the tiny Pacific Island nation of Tuvalu that is preparing to abandon its home due to rising sea levels. The site takes a look at this subject and the resulting increased beach erosion that takes place around the world. Visitors can read about the physical processes of beach erosion, view a QuickTime movie of a house falling into the ocean, and more. The site includes good descriptions, photographs, and links to additional information (although some were broken at the time of this annotation), giving interested readers insight into this widespread phenomenon.

1999-01-01

123

From structure- to erosion-controlled subsiding calderas: evidence thresholds and mechanics  

NASA Astrophysics Data System (ADS)

Collapse calderas evolve by increasing their depth/diameter ratio. To properly characterize caldera evolution, a structural S/D (ratio between structural subsidence and ring-fault diameter; S s / D s ), and a topographic S/D (ratio between topographic caldera depth and topographic caldera width; S t / D t ), are considered. We review the evolution of the A.D. 2000 Miyakejima caldera, with two concentric ring faults at earlier collapsing stages, and erosion of its wall, accumulating debris on the floor, at later collapsing stages. While S t / D t and S s / D s show a similar increase at initial stages, when S s / D s ˜0.33 the S s / D s becomes significantly different from S t / D t : while continuous caldera subsidence monotonically increases S s / D s , the erosion of the wall and the filling of the floor decrease S t / D t . This evolution finds close similarities with recent caldera collapses of Krakatau (1883), Katmai (1912), Fernandina (1968), Tolbachik (1975-1976), Pinatubo (1991), and Dolomieu (2007). Analog experiments mimic the observed variation, evolving from a depression controlled by the activity of the double-ring faults to that controlled by the erosion of the wall and sedimentation at the floor. These natural and modeling results show that the control on the shape of mature calderas ( S s / D s > 0.07) and approaching S s / D s = 0.3-0.4 passes from a mainly structural to a mainly erosional control. Both S t / D t and S s / D s are needed to describe the evolution of a collapse and the processes accompanying it. Evaluating S t / D t and S s / D s allows proper description of the precise evolutionary stage of a caldera and of the relative importance of the structural and erosional processes and allows making semiquantitative comparisons between evolutionary stages.

Geshi, Nobuo; Acocella, Valerio; Ruch, Joel

2012-08-01

124

Costs and benefits of urban erosion and sediment control: The North Carolina experience  

NASA Astrophysics Data System (ADS)

The EPA’s new nonpoint source pollution control requirements will soon institutionalize urban erosion and sediment pollution control practices nationwide. The public and private sector costs and social benefits associated with North Carolina’s program (one of the strongest programs in the country in terms of implementation authority, staffing levels, and comprehensiveness of coverage) are examined to provide general policy guidance on questions relating to the likely burden the new best management practices will have on the development industry, the likely costs and benefits of such a program, and the feasibility of running a program on a cost recovery basis. We found that urban erosion and sediment control requirements were not particularly burdensome to the development industry (adding about 4% on average to development costs). Public-sector program costs ranged between 2.4 and 4.8 million in fiscal year 1989. Our contingent valuation survey suggests that urban households in North Carolina are willing to pay somewhere between 7.1 and 14.2 million a year to maintain current levels of sediment pollution control. Our benefit-cost analysis suggests that the overall ratio is likely to be positive, although a definitive figure is elusive. Lastly, we found that several North Carolina localities have cost recovery fee systems that are at least partially self-financing.

Paterson, Robert G.; Luger, Michael I.; Burby, Raymond J.; Kaiser, Edward J.; Malcom, H. Rooney; Beard, Alicia C.

1993-03-01

125

Materials for Advanced Turbine Engines (MATE). Project 4: Erosion resistant compressor airfoil coating  

NASA Technical Reports Server (NTRS)

The ability of coatings to provide at least a 2X improvement in particulate erosion resistance for steel, nickel and titanium compressor airfoils was identified and demonstrated. Coating materials evaluated included plasma sprayed cobalt tungsten carbide, nickel carbide and diffusion applied chromium plus boron. Several processing parameters for plasma spray processing and diffusion coating were evaluated to identify coating systems having the most potential for providing airfoil erosion resistance. Based on laboratory results and analytical evaluations, selected coating systems were applied to gas turbine blades and evaluated for surface finish, burner rig erosion resistance and effect on high cycle fatigue strength. Based on these tests, the following coatings were recommended for engine testing: Gator-Gard plasma spray 88WC-12Co on titanium alloy airfoils, plasma spray 83WC-17Co on steel and nickel alloy airfoils, and Cr+B on nickel alloy airfoils.

Rashid, J. M.; Freling, M.; Friedrich, L. A.

1987-01-01

126

Can warmwater streams be rehabilitated using watershed-scale standard erosion control measures alone?  

PubMed

Degradation of warmwater streams in agricultural landscapes is a pervasive problem, and reports of restoration effectiveness based on monitoring data are rare. Described is the outcome of rehabilitation of two deeply incised, unstable sand-and-gravel-bed streams. Channel networks of both watersheds were treated using standard erosion control measures, and aquatic habitats within 1-km-long reaches of each stream were further treated by addition of instream structures and planting woody vegetation on banks ("habitat rehabilitation"). Fish and their habitats were sampled semiannually during 1-2 years before rehabilitation, 3-4 years after rehabilitation, and 10-11 years after rehabilitation. Reaches with only erosion control measures located upstream from the habitat measure reaches and in similar streams in adjacent watersheds were sampled concurrently. Sediment concentrations declined steeply throughout both watersheds, with means > or = 40% lower during the post-rehabilitation period than before. Physical effects of habitat rehabilitation were persistent through time, with pool habitat availability much higher in rehabilitated reaches than elsewhere. Fish community structure responded with major shifts in relative species abundance: as pool habitats increased after rehabilitation, small-bodied generalists and opportunists declined as certain piscivores and larger-bodied species such as centrarchids and catostomids increased. Reaches without habitat rehabilitation were significantly shallower, and fish populations there were similar to the rehabilitated reaches prior to treatment. These findings are applicable to incised, warmwater streams draining agricultural watersheds similar to those we studied. Rehabilitation of warmwater stream ecosystems is possible with current knowledge, but a major shift in stream corridor management strategies will be needed to reverse ongoing degradation trends. Apparently, conventional channel erosion controls without instream habitat measures are ineffective tools for ecosystem restoration in incised, warmwater streams of the Southeastern U.S., even if applied at the watershed scale and accompanied by significant reductions in suspended sediment concentration. PMID:17464528

Shields, F Douglas; Knight, Scott S; Cooper, Charles M

2007-07-01

127

Analysis/control of in-bed tube erosion phenomena in the fluidized bed combustion (FBC) system. Technical progress report No. 2, [January 1, 1993--March 31, 1993  

SciTech Connect

This technical report summarizes the research work performed and the progress achieved during the period of January 1, 1993 to March 31, 1993. The prototype dust collector as a part of the exhaust system was designed and fabricated to perform the well-controlled test in the bench-scale FBC system. The instrumentation for flow-measuring has been conducted in the system, which includes the minimum fluidization velocity and bed-pressure drop, mean gas velocity, calculation of particle terminal velocity and its operating range, and static pressure distribution in the system. The bubble velocity was also predicted. The project has been progressing well. Future efforts will be concentrated on instrumentation for erosion-measuring. In addition to that, instrumentation for flow-measuring will be continued to support the erosion-measuring. Theoretical analysis and modeling on in-bed tube erosion will be initiated along with the experimental results. Experience and observation of in-bed tube erosion will be predicted.

Lee, Seong W.

1993-06-01

128

Corrective measures technology for shallow land burial at arid sites: field studies of biointrusion barriers and erosion control  

SciTech Connect

The field research program involving corrective measures technologies for arid shallow land burial (SLB) sites is described. Results of field testing of a biointrusion barrier installed at a close-out waste disposal site (Area B) at Los Alamos are presented. Soil erosion and infiltration of water into a simulated trench cap with various surface treatments were measured, and the interaction between erosion control and subsurface water dynamics is discussed relative to waste management.

Nyhan, J.W.; Hakonson, T.E.; Lopez, E.A.

1986-03-01

129

Substation control and protection project  

SciTech Connect

This report describes the results of EPRI-sponsored Project RP1359-7, dealing with digital protection and control of transmission class substations. Earlier work involved a study of the feasibility of an integrated protection and control system, specification of functional requirements and selection of the optimum architecture for the system. An integrated system including line, bus and transformer protection was designed, built and laboratory tested. It was subsequently installed at the Deans substation of Public Service Electric and Gas (New Jersey). A standalone, digital transmission line system was built and installed at the Branchburg substation of PSE G, for coordinated line protection with the integrated system. The system is called WESPAC, an acronym for Westinghouse Substation Protection and Control. 52 refs., 174 figs.

Cassel, R.L.; Deliyannides, J.S.; Dzieduszko, J.W.; Harvey, J.H.; Hertz, L.H.; Klancher, F.; Mays, L.M.; McGarry, M.J.; Pettis, L.G.; Pistolese, L.F.; Reuther, J.F.; Sackin, M.; Szarmach, D.J.; Udren, E.A. (Westinghouse ABB Power T and D Co., Coral Springs, FL (USA). Relay and Telecommunications Div.)

1990-04-01

130

Low cost forged Y-pattern valves control hot corrosive/erosive gases  

SciTech Connect

The Morgantown Energy Technology Center in Morgantown, West Virginia is a research facility of the US Department of Energy (DOE) that does research on fossil fuels utilization and conversion to provide improved and environmentally acceptable energy sources. One area of investigation in the Morgantown facility is the use of gaseous fuels derived from coal from fluidized-bed and fixed-bed gasification technologies. The corrosive and slightly erosive gases and vapors at about 1000F and from 100 to 300 psi are treated in an experimental desulfurization unit to produce fuel gas with greatly enhanced environmental characteristics. The valves in use were constructed of Type 347 stainless steel, a stabilized version of 316 SS, and cost about $6000 for the 2'' size and about $4000 for the 1'' size. Despite the high cost, the valve sometimes became difficult or impossible to operate due to metal failures. The Technology Center had a number of new Class 1500 Y-pattern (angle-style) globe valves in inventory. The control valve body and bonnet are forged chrome moly steel (ASTM-H182-F22), the stem assembly is a 13% chrome alloy with an erosion resistant hard faced disc, and the seat ring is a cobalt-base alloy fused in place as an integral part of the body. Stem packing as an either wire inserted molded asbestos or Grafoil flexible graphite. The Y-pattern globe valves in 1 and 2'' sizes, which were judged potentially suitable and on hand, were installed in the experimental desulfization unit as well as in the connecting hot gas piping system to a new coal gasification process. The Class 1500 Y-pattern valves have provided reliable control of the hot corrosive and erosive gas streams with very little maintenance.

Gaines, A.

1987-06-01

131

GEOWEPP-THE GEO-SPATIAL INTERFACE FOR THE WATER EROSION PREDICTION PROJECT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Decision-makers operating at different scales of interest and responsibility have to assess the distribution, extent, and severity of soil erosion and sedimentation. To seek solutions in handling natural and human actions related to this type of nonpoint source pollution, the linkage of distributed ...

132

Ecosystem services in Mediterranean river basin: climate change impact on water provisioning and erosion control.  

PubMed

The Mediterranean basin is considered one of the most vulnerable regions of the world to climate change and such changes impact the capacity of ecosystems to provide goods and services to human society. The predicted future scenarios for this region present an increased frequency of floods and extended droughts, especially at the Iberian Peninsula. This paper evaluates the impacts of climate change on the water provisioning and erosion control services in the densely populated Mediterranean Llobregat river basin of. The assessment of ecosystem services and their mapping at the basin scale identify the current pressures on the river basin including the source area in the Pyrenees Mountains. Drinking water provisioning is expected to decrease between 3 and 49%, while total hydropower production will decrease between 5 and 43%. Erosion control will be reduced by up to 23%, indicating that costs for dredging the reservoirs as well as for treating drinking water will also increase. Based on these data, the concept for an appropriate quantification and related spatial visualization of ecosystem service is elaborated and discussed. PMID:23660520

Bangash, Rubab F; Passuello, Ana; Sanchez-Canales, María; Terrado, Marta; López, Alfredo; Elorza, F Javier; Ziv, Guy; Acuña, Vicenç; Schuhmacher, Marta

2013-08-01

133

Coercive versus cooperative pollution control: Comparative study of state programs to reduce erosion and sedimentation pollution in urban areas  

NASA Astrophysics Data System (ADS)

This article examines coercive and cooperative approaches to implementing state urban erosion and sedimentation pollution control programs. State administrators report serious shortfalls in their ability to control sources of pollution, but comparison of more and less successful programs provides evidence of what states can do to make programs more effective. Key ingredients for a successful state effort include the use of coercion with both the private sector and local government, adequate staffing, application of severe sanctions when violations of state standards are detected, and provision of technical assistance. Many state programs lack one or more of those elements, which explains their inability to adequately control urban erosion and sedimentation pollution.

Burby, Raymond J.

1995-05-01

134

Soil tillage conservation and its effect on erosion control, water management and carbon sequestration  

NASA Astrophysics Data System (ADS)

The energetic function of the soil expressed through the potential energy accumulated through humus, the biogeochemical function (the circuit of the nutrient elements) are significantly influenced by its hydrophysical function and especially by the state of the bedding- consolidation, soil capacity of retaining an optimal quantity of water, and then its gradual disponibility for plant consumption. The understanding of soil functions and management including nutrient production, stocking, filtering and transforming minerals, water , organic matter, gas circuit and furnishing breeding material, all make the basis of human activity, Earth's past, present and especially future. The minimum tillage soil systems - paraplow, chisel or rotary grape - are polyvalent alternatives for basic preparation, germination bed preparation and sowing, for fields and crops with moderate loose requirements being optimized technologies for: soil natural fertility activation and rationalization, reduction of erosion, increasing the accumulation capacity for water and realization of sowing in the optimal period. By continuously applying for 10 years the minimum tillage system in a crop rotation: corn - soy-bean - wheat - potato / rape, an improvement in physical, hydro-physical and biological properties of soil was observed, together with the rebuilt of structure and increase of water permeability of soil. The minimum tillage systems ensure an adequate aerial-hydrical regime for the biological activity intensity and for the nutrients solubility equilibrium. The vegetal material remaining at the soil surface or superficially incorporated has its contribution to intensifying the biological activity, being an important resource of organic matter. The minimum tillage systems rebuild the soil structure, improving the global drainage of soil which allows a rapid infiltration of water in soil. The result is a more productive soil, better protected against wind and water erosion and needing less fuel for preparing the germination bed. Presently it is necessary a change concerning the concept of conservation practices and a new approach regarding the control of erosion. The real conservation of soil must be expanded beyond the traditional understanding of soil erosion. The real soil conservation is represented by carbon management. We need to focus to another level concerning conservation by focusing on of soil quality. Carbon management is necessary for a complex of matters including soil, water management, field productivity, biological fuel and climatic change.

Rusu, T.; Gus, P.; Bogdan, I.; Moraru, P.; Pop, A.; Clapa, D.; Pop, L.

2009-04-01

135

Soil tillage conservation and its effect on erosion control, water management and carbon sequestration  

NASA Astrophysics Data System (ADS)

The energetic function of the soil expressed through the potential energy accumulated through humus, the biogeochemical function (the circuit of the nutrient elements) are significantly influenced by its hydrophysical function and especially by the state of the bedding- consolidation, soil capacity of retaining an optimal quantity of water, and then its gradual disponibility for plant consumption. The understanding of soil functions and management including nutrient production, stocking, filtering and transforming minerals, water , organic matter , gas circuit and furnishing breeding material, all make the basis of human activity, Earth's past, present and especially future. The minimum tillage soil systems - paraplow, chisel or rotary grape - are polyvalent alternatives for basic preparation, germination bed preparation and sowing, for fields and crops with moderate loose requirements being optimized technologies for: soil natural fertility activation and rationalization, reduction of erosion, increasing the accumulation capacity for water and realization of sowing in the optimal period. By continuously applying for 10 years the minimum tillage system in a crop rotation: corn - soy-bean - wheat - potato / rape, an improvement in physical, hydro-physical and biological properties of soil was observed, together with the rebuilt of structure and increase of water permeability of soil. The minimum tillage systems ensure an adequate aerial-hydrical regime for the biological activity intensity and for the nutrients solubility equilibrium. The vegetal material remaining at the soil surface or superficially incorporated has its contribution to intensifying the biological activity, being an important resource of organic matter. The minimum tillage systems rebuild the soil structure, improving the global drainage of soil which allows a rapid infiltration of water in soil. The result is a more productive soil, better protected against wind and water erosion and needing less fuel for preparing the germination bed. Presently it is necessary a change concerning the concept of conservation practices and a new approach regarding the control of erosion. The real conservation of soil must be expanded beyond the traditional understanding of soil erosion. The real soil conservation is represented by carbon management. We need to focus to another level concerning conservation by focusing on of soil quality. Carbon management is necessary for a complex of matters including soil, water management, field productivity, biological fuel and climatic change. Profound research is necessary in order to establish the carbon sequestration practices and their implementation impact.

Rusu, Dr.; Gus, Dr.; Bogdan, Dr.; Moraru, Dr.; Pop, Dr.; Clapa, Dr.; Pop, Drd.

2009-04-01

136

Cropping systems and control of soil erosion in a Mediterranean environment  

NASA Astrophysics Data System (ADS)

The research has been carried out over the years 1996-2010 in an area of the internal hill of Sicily region (Enna, c.da Geracello, 550 m a. s. l. 37° 23' N. Lat, 14° 21' E. Long) in the center of Mediterranean Sea, mainly devoted to durum wheat cultivation, using the experimental plots, established in 1996 on a slope of 26-28%, equipped to determine surface runoff and soil losses. The establishment consists of twelve plots, having 40 m length and 8 m width. In order to study the effect of different field crop systems in controlling soil erosion in slopes subjected to water erosion, the following systems were studied: permanent crops, tilled annual crops, no-tilled annual crops, set-aside. The used crops were: durum wheat, faba bean, rapeseed, subterranean clover, Italian ryegrass, alfalfa, sweetvetch, moon trefoil, barley, sweet sorghum, sunflower. The results pointed out that the cropping systems with perennial crops allowed to keep low the soil loss, while annual crop rotation determined a high amount of soil loss. Sod seeding showed promising results also for annual crop rotations.

Cosentino, Salvatore; Copani, Venera; Testa, Giorgio; Scalici, Giovanni

2013-04-01

137

Structural controls on the orientation of erosion gullies in mid-western New South Wales, Australia  

NASA Astrophysics Data System (ADS)

The role of geology in determining the drainage network of gullying has been evaluated by quantitative methods of analysis. At gully erosion sites in New South Wales, field evidence suggests that soil cracks are sites of preferential flow and erosion at both the surface and subsurface. Soil fabric and rock structure and weathering studies were undertaken to establish the inheritance of soil cracks from the underlying parent material. Gully orientation was correlated with the strike of joints and bedding planes in a range of rock materials, including sedimentary, intrusive and extrusive igneous, and thermal and regional metamorphic rocks. These units vary not only in terms of mineralogy but also in degree of weathering. However, all are steeply dipping structures (usually exceeding 60°). Correlations exist between gully orientation and joints in the underlying material, but the strength of the relationship varies according to the parent material. In the Ordovician hornfels, where no correlation between joints and gully orientation occurred, the evidence showed that gullying was controlled by faulting along the hornfels-granite boundary. These relationships support the view that throughflow processes are dominant in the development of gullies, since convergence of runoff would not be expected to align with subsurface soil discontinuities.

Beavis, Sara G.

2000-05-01

138

In Situ analysis of CO2 laser irradiation on controlling progression of erosive lesions on dental enamel.  

PubMed

The present study aimed to evaluate in situ the effect of CO2 laser irradiation to control the progression of enamel erosive lesions. Fifty-six slabs of bovine incisors enamel (5 × 3 × 2.5 mm(3) ) were divided in four distinct areas: (1) sound (reference area), (2) initial erosion, (3) treatment (irradiated or nonirradiated with CO2 laser), (4) final erosion (after in situ phase). The initial erosive challenge was performed with 1% citric acid (pH?=?2.3), for 5 min, 2×/day, for 2 days. The slabs were divided in two groups according to surface treatment: irradiated with CO2 laser (??=?10.6 µm; 0.5 W) and nonirradiate. After a 2-day lead-in period, 14 volunteers wore an intraoral palatal appliance containing two slabs (irradiated and nonirradiated), in two intraoral phases of 5 days each. Following a cross-over design during the first intraoral phase, half of the volunteers immersed the appliance in 100 mL of citric acid for 5 min, 3×/day, while other half of the volunteers used deionized water (control). The volunteers were crossed over in the second phase. Enamel wear was determined by an optical 3D profilometer. Three-way ANOVA for repeated measures revealed that there was no significant interaction between erosive challenge and CO2 laser irradiation (P?=?0.419). Erosive challenge significantly increased enamel wear (P?=?0.001), regardless whether or not CO2 laser irradiation was performed. There was no difference in enamel wear between specimens CO2 -laser irradiated and non-irradiated (P?=?0.513). Under intraoral conditions, CO2 laser irradiation did not control the progression of erosive lesions in enamel caused by citric acid. PMID:24825789

Lepri, Taísa Penazzo; Scatolin, Renata Siqueira; Colucci, Vivian; De Alexandria, Adílis Kalina; Maia, Lucianne Cople; Turssi, Cecília Pedroso; Corona, Silmara Aparecida Milori

2014-08-01

139

UMTRA Project document control system manual  

SciTech Connect

This manual defines the Project Document Control System (PDCS) operated by the US DOE Uranium Mill tailings Remedial Action (UMTRA) project Office. The purpose of the PDCS is to provide an active and continuing program for acquiring, controlling, retaining, retrieving, retiring and disposing of all UMTRA Project documents. The PDCS also provides guidance and coordination in transferring documents by various UMTRA Projection document control centers to a central location.

Not Available

1994-09-01

140

Robotic weld overlay coatings for erosion control. Quarterly progress report, October 1993--December 1993  

SciTech Connect

Research is being conducted to develop criteria for selecting weld overlay coatings for erosion mitigation in Circulated Fluidized Beds. Twelve weld overlay alloys were deposited on 1018 steel substrates using plasma arc welding. Ten samples from each coating were prepared for erosion testing. All selected coatings were erosion tested at 400C and their erosion resistance and microstructure evaluated. Steady state erosion rates were similar for several weld overlay coatings (Ultimet, Inconel-625, Iron-Aluminide, 316L SS, and High Chromium Cast Iron) and were considerably lower than the remaining coating evaluated. These coatings had different base (Co, Fe, Ni-base). No correlations were found between room temperature microhardness of the weld overlay coatings and their erosion resistance at elevated temperature, although this criteria is often thought to be an indicator of erosion resistance. It was suggested that the coatings that showed similar erosion rates may have similar mechanical properties such as fracture strength, toughness and work hardening rates at this temperature. During the past quarter, Iron-Aluminide, Inconel-625, and 316L SS coatings were selected for more detailed investigations based upon the preliminary erosion test results. Microhardness tests were performed on eroded samples to determine the size of the work hardened zone and change in coatings hardness due to erosion. The work hardened zone was to correlated with erosion resistance of the coatings. Additional Iron-Aluminide, Inconel-625, and 316L SS coatings were deposited on 1018 steel substrates.

Levin, B.F.; DuPont, J.N.; Marder, A.R.

1994-01-20

141

Validation of Erosion 3D in Lower Saxony - Comparison between modelled soil erosion events and results of a long term monitoring project  

NASA Astrophysics Data System (ADS)

Since 2000 water erosion has been surveyed on 400 ha arable land in three different regions of Lower Saxony (Mosimann et al. 2009). The results of this long-term survey are used for the validation of the soil erosion models such as USLE and Erosion 3D. The validation of the physically-based model Erosion 3D (Schmidt & Werner 2000) is possible because the survey analyses the effects (soil loss, sediment yield, deposition on site) of single thunder storm events and also maps major factors of soil erosion (soil, crop, tillage). A 12.5 m Raster DEM was used to model the soil erosion events.Rainfalldata was acquired from climate stations. Soil and landuse parameters were derived from the "Parameterkatalog Sachsen"(Michael et al. 1996). During thirteen years of monitoring, high intensity storms fell less frequently than expected. High intensity rainfalls with a return period of five or ten years usually occurred during periods of maximum plant cover.Winter events were ruled out because dataon snow melt and rainfallwere not measured. The validation is therefore restricted to 80 events. The validation consists of three parts. The first part compares the spatial distribution of the mapped soil erosion with the model results. The second part calculates the difference in the amount of redistributed soil. The third part analyses off-site effects such as sediment yield and pollution of water bodies. The validation shows that the overall result of erosion 3D is quite good. Spatial hotspots of soil erosion and of off-site effects are predicted correctly in most cases. However, quantitative comparison is more problematic, because the mapping allows only the quantification of rillerosion and not of sheet erosion. So as a rule,the predicted soil loss is higher than the mapped. The prediction of rill development is also problematic. While the model is capable of predicting rills in thalwegs, the modelling of erosion in tractor tracks and headlands is more complicated. In order to obtain better results, the DEM needs a higher resolution, and soil and landuse parameters have to been optimized in tractor tracks and headlands (higher bulk density, less coverage). Other models like LINERO (Bug &Mosimann 2012) can help to get an overview over the location of erosion forms and the soil loss due to rill erosion. References: Bug J., & T. Mosimann (2012): Modellierung der linearen Bodenerosion. Entwicklung eines entscheidungsbasierten Modells zur flächenhaften Prognose der linearen Erosionsaktivität, Geosynthesis 15, Hannover, 105 S. Michael, A., Schmidt, J. & W. A. Schmidt (1996): EROSION 2D/3D - Ein Computermodell zur Simulation der Bodenerosion durch Wasser. Parameterkatalog Sachsen, Freiberg. Mosimann, T., Bug, J. Sanders, S. & F. Beisiegel (2009): Bodenerosionsdauerbeobachtung in Niedersachsen 2000-2008. Methodik, Erosionsgeschehen, Bodenabträge und Anwendung der Ergebnisse, Geosynthesis 14, Hannover, 101 S. Schmidt, J., & M. v. Werner (2000): Modeling sediment and heavy metal yields of drinking water reservoirs in the Osterzgebirge region of Saxony (Germany). In: Schmidt, J. (Ed.), Soil Erosion—Application of Physically Based Models. Springer, Berlin, Heidelberg, New York, pp. 93- 108.

Bug, Jan; Mosimann, Thomas

2013-04-01

142

Robotic weld overlay coatings for erosion control. Quarterly technical progress report, July--September, 1994  

SciTech Connect

Research is presently being conducted to develop a criteria for selecting weld overlay coatings for erosion mitigation in Circulated Fluidized Beds. Initially, eleven weld overlay alloys were selected for erosion testing based upon a literature review. All eleven coatings were deposited on 1018 steel substrates using the plasma arc welding process. Ten samples from each coating were prepared for erosion testing. All selected coatings were erosion tested at 400 C and their erosion resistance was evaluated by determining the steady state erosion rate. In addition, the microstructure of each coating was characterized before and after the erosion tests. No correlations were found between room temperature hardness of the weld overlay coatings and their erosion resistance at elevated temperature. It was suggested that weld overlays mechanical properties such as fracture strength, toughness and work hardening rates may contributed to their erosion resistance. During the previous two quarters the microhardness tests were performed on the eroded samples in order to determine the size of the work hardened zone and the change in the coatings hardness due to erosion. As a result of these measurements it was established that one group of coatings deformed plastically, while another did not. In addition, the measurements of the weld overlays microhardness at 400 C were made. The coatings microhardness at 400 C was plotted versus their volume erosion rates. During the last quarter, erosion tests were performed for Inconel-625, 316L SS, and Iron-Aluminide wrought alloys in order to compare their erosion behavior with similar weld overlays. The results of microhardness profile measurements for all weld overlay coatings were analyzed. The factors that contribute to the erosion resistance of the coatings that deformed plastically are discussed in this progress report.

Levin, B.F.; Dupont, J.N.; Marder, A.R.

1994-10-26

143

Combined Wind and Water Erosion Modeling  

Technology Transfer Automated Retrieval System (TEKTRAN)

Current soil erosion prediction technologies in the United States for water and wind erosion are vastly different. An effort is underway to create a combined process-based water and wind erosion model, based upon the technologies in the USDA Water Erosion Prediction Project (WEPP) and Wind Erosion P...

144

Robotic weld overlay coatings for erosion control. Quarterly technical progress report, October 1994--December 1994  

SciTech Connect

Research is presently being conducted to develop a criteria for selecting weld overlay coatings for erosion mitigation in Circulated Fluidized Beds. Initially, eleven weld overlay alloys were selected for erosion testing based upon a literature review. All eleven coatings were deposited on 1018 steel substrates using the plasma arc welding process. Ten samples from each coating were prepared for erosion testing. The coating deposition and sample preparation procedures were described in the second quarterly report. All selected coatings were erosion tested at 400{degree}C and their erosion resistance was evaluated by determining the steady state erosion rate. In addition, the microstructure of each coating was characterized before and after the erosion tests. The results of the tests are discussed in the third quarterly report. No correlations were found between room temperature hardness of the weld overlay coatings and their erosion resistance at elevated temperature. During the last quarter tensile tests were performed at 400{degree}C for the Ultimet, Inconel-625, 316L SS, C-22, and Stellite-6 wrought alloys. The erosion tests for these materials at 400{degree}C are in progress. The results of mechanical and erosion tests will be used to correlate mechanical properties of selected wrought alloys such as tensile toughness, ductility, strain hardening coefficient and yield strength to their erosion resistance at 400{degree}C. Also, the erosion behavior of the wrought alloys compared with similar weld alloys will be analyzed. The experimental procedure and results of the tensile tests are presented in this progress report.

Levin, B.F.; Dupont, J.N.; Marder, A.R.

1995-01-25

145

NASA's Evolutionary Xenon Thruster (NEXT) Project Qualification Propellant Throughput Milestone: Performance, Erosion, and Thruster Service Life Prediction After 450 kg  

NASA Technical Reports Server (NTRS)

The NASA s Evolutionary Xenon Thruster (NEXT) program is tasked with significantly improving and extending the capabilities of current state-of-the-art NSTAR thruster. The service life capability of the NEXT ion thruster is being assessed by thruster wear test and life-modeling of critical thruster components, such as the ion optics and cathodes. The NEXT Long-Duration Test (LDT) was initiated to validate and qualify the NEXT thruster propellant throughput capability. The NEXT thruster completed the primary goal of the LDT; namely to demonstrate the project qualification throughput of 450 kg by the end of calendar year 2009. The NEXT LDT has demonstrated 28,500 hr of operation and processed 466 kg of xenon throughput--more than double the throughput demonstrated by the NSTAR flight-spare. Thruster performance changes have been consistent with a priori predictions. Thruster erosion has been minimal and consistent with the thruster service life assessment, which predicts the first failure mode at greater than 750 kg throughput. The life-limiting failure mode for NEXT is predicted to be loss of structural integrity of the accelerator grid due to erosion by charge-exchange ions.

Herman, Daniel A.

2010-01-01

146

Use of hold-gro erosion control fabric in the establishment of plant species on coal mine soil.  

PubMed

Experiments were conducted on the Black Mesa Coal Mine, Kayenta, Arizona in 1977 and 1978 to study the effectiveness of Hold-Gro Erosion Control Fabric (a product from the Gulf States Paper Corporation, Tuscaloosa, Alabama) in the establishment of plants on coal mine soil following the surface mining of coal. Four plant species were planted: (1) spring barley (Horduem vulgare L.), an annual grass (2) crested wheatgrass (Agropyron cristatum L.), a perennial grass (3) alfalfa (lucerne) (Medicago sativa L.), a perennial legume and (4) fourwing saltbush (Atriplex canescens Pursh.), a perennial shrub. Seeds of each plant species were planted in reclaimed coal mine soil in the spring of the year by both broadcast seeding (conventional culture) and the incorporation of seeds in Hold-Gro Erosion Control Fabric. Average numbers of seedlings established and percent ground cover for all species studied were higher in areas where conventional culture was used than they were in areas where seeds were incorporated in Hold-Gro Erosion Control Fabric. The incorporation of seeds in Hold-Gro Erosion Control Fabric in the establishment of plant species on coal mine soil was not an effective cultural practice in the southwestern United States. PMID:24214010

Day, A D; Ludeke, K L

1986-09-01

147

Open Innovation and the Erosion of the Traditional Information Systems Project's Boundaries  

NASA Astrophysics Data System (ADS)

This paper examines the notion of open innovation and its implication on information systems management. It investigates a project of an enterprise resource planning system implementation in an international organization to unravel the resemblance with the open innovation model. The study shows that the conceptualization of ERP project as an open innovation could reveal the complex architecture of today's organization from which the ERP project cannot be isolated. It argues that the traditional boundaries around IS projects are dissolving and the relationship between what used to be outside and what used to be inside the project is increasingly blurred. The study calls for a different perspective of project management that goes beyond single and multiple project management to scan the open space of innovation and actively look for partners, competitors, and collaborators.

Elbanna, Amany

148

Cost effectiveness of conservation practices in controlling water erosion in Iowa  

Microsoft Academic Search

Iowa has severe water-induced soil erosion and associated water quality concerns because of intense agricultural activities. The objective of this study was to determine the effectiveness and economic benefits of selected conservation practices in sediment reduction by water erosion in major soil areas of Iowa. One farm was selected to represent the typical soil and slope gradient in each of

X. Zhou; M. Al-Kaisi; M. J. Helmers

2009-01-01

149

Weld overlay coatings for erosion control. Task A: Literature review, progress report  

SciTech Connect

A literature review was made. In spite of similarities between abrasive wear and solid particle erosion, weld overlay hardfacing alloys that exhibit high abrasion resistance may not necessarily have good erosion resistance. The performance of weld overlay hardfacing alloys in erosive environments has not been studied in detail. It is believed that primary-solidified hard phases such as carbides and intermetallic compounds have a strong influence on erosion resistance of weld overlay hardfacing alloys. However, relationships between size, shape, and volume fraction of hard phases in a hardfacing alloys and erosion resistance were not established. Almost all hardfacing alloys can be separated into two major groups based upon chemical compositions of the primary solidified hard phases: (a) carbide hardening alloys (Co-base/carbide, WC-Co and some Fe base superalloys); and (b) intermetallic hardening alloys (Ni-base alloys, austenitic steels, iron-aluminides).

Levin, B.; DuPont, J.N.; Marder, A.R.

1993-03-03

150

Robotic weld overlay coatings for erosion control. Quarterly technical progress report, January 1995--March 1995  

SciTech Connect

Research is presently being conducted to develop a criteria for selecting weld overlay coatings for erosion mitigation in Circulated Fluidized Beds. During the last two quarters tensile tests were performed at 400{degrees}C for the Ultimet, Inconel-625, 316L SS, C-22, and Stellite-6 wrought alloys. Also, the erosion tests for these materials at 400{degrees}C were completed. The results of mechanical and erosion tests are used to correlate mechanical properties of selected wrought alloys such as tensile toughness, ductility, strain hardening coefficient and yield strength to their erosion resistance at 400{degrees}C. Preliminary results of correlations between erosion resistance of wrought alloys at 400{degrees}C and their mechanical properties are presented in this progress report.

Levin, B.F.; Dupont, J.N.; Marder, A.R.

1995-04-25

151

WEPPCAT: An Online tool for assessing and managing the potential impacts of climate change on sediment loading to streams using the Water Erosion Prediction Project (WEPP) Model  

EPA Science Inventory

WEPPCAT is an on-line tool that provides a flexible capability for creating user-determined climate change scenarios for assessing the potential impacts of climate change on sediment loading to streams using the USDA?s Water Erosion Prediction Project (WEPP) Model. In combination...

152

Identifying Erosion  

NSDL National Science Digital Library

In this environmental science activity (page 3 of the PDF), leaners will identify and explain the causes of erosion. They will observe the effects of erosion on the surrounding area and further explore examples of erosion online. An extension activity allows learners to make a hands-on model of soil erosion. Though this was created as a pre-visit activity for a workshop about water flow and erosion, it makes a great stand-alone activity as well!

Cosi

2009-01-01

153

Contour Ripping and Composted Dairy Manure for Erosion Control on Fort Hood Military Installation, Texas  

E-print Network

erosion. This investigation examined two conservation practices directed at improving and creating sustainable training conditions on Fort Hood training lands, contour ripping and the application of composted dairy manure. The application of composted...

Prcin, Lisa J.

2010-07-14

154

Holocene Fire, Climate and Erosion in the Jemez Mountains, New Mexico: Natural and Anthropogenic Controls  

NASA Astrophysics Data System (ADS)

Ponderosa pine and mixed-conifer forests in the Jemez Mountains have been ravaged by extensive severe fires in the last two decades, which burned almost 1000 km2, roughly 30% of this middle-elevation range. Tree-ring fire history reconstructions indicate that a low-severity fire regime characterized the ca. 400 years before Euroamerican settlement, and that fuel buildup from fire suppression and land-use impacts contributed to increased fire severity in recent years. In order to better understand natural variability, climatic influences, and erosional effects of wildfire activity since ~5000 cal yr BP, we identified and 14C-dated fire-related alluvial deposits in the 2002 Lakes Fire area in the southwestern Jemez Mountains. These deposits indicate that most late Holocene fire-related erosional events were relatively minor, consistent with the low-severity burns that dominate the tree-ring record, but larger debris flows also occurred, suggesting at least small areas of high-severity fire. Although changes in postfire sedimentation are not so clearly related to millennial-scale Holocene climatic changes as in the Northern Rocky Mountains, peaks in fire-event probability correspond with severe regional multidecadal droughts ca. 1800 and 375 cal yr BP. Local microclimatic controls on vegetation, soils, and post-fire sedimentation are also evident. Relatively dense mixed-conifer stands including Douglas-fir typify moister north-facing basins, where soils are apparently thicker and more permeable than on southerly aspects. Alluvial fans of these basins are dominated by fire-related deposits (77% of measured stratigraphic thickness), thus we interpret that little erosion occurs in the absence of wildfires. Holocene fire-related events from north slopes are also of somewhat lower frequency, and possibly of higher severity. In contrast, in ponderosa pine-dominated south-facing basins, fire-related deposits make up only 39% of measured fan deposits. On drier south aspects, thin soils, large areas of steep exposed bedrock, and sparser vegetation allow greater runoff and sediment in the absence of fire, making for a lesser relative importance of fire in erosion. The lack of exposed and dated deposits older than 5000 cal yr BP, even where fan feeder channels were incised to bedrock in debris-flow and flood events after the 2002 Lakes Fire, indicates that most stored alluvium was scoured from these channels in the middle Holocene, possibly from more severe fires and postfire erosion. It also suggests that erosional response after the Lakes Fire was at least locally greater than at any time in the last 5000 yr, possibly from the combined influence of fire suppression and recent warming and severe drought. However, expansion of this small study area would allow a clearer view of fire-climate-erosional linkages in the Jemez Mountains, and the degree to which modern climatic warming and anthropogenic impacts have heightened severe fire activity.

Meyer, G. A.; Fitch, E. P.

2013-12-01

155

Reducing Erosion and Runoff  

NSDL National Science Digital Library

Reducing Erosion and Runoff, from the Virginia Cooperative Extension, describes what erosion and runoff are, methods of control, including the use of plants and groundcover selection. The site also describes how to handle steep slopes and some steps for building and protecting soil. This information can also be downloaded as a pdf.

2008-07-24

156

Design projects for digital and process control courses  

Microsoft Academic Search

Design projects for two advanced undergraduate control courses: process instrumentation and control engineering; and digital control, are discussed. Projects emphasize practical as well as theoretical aspects of design and implementation of control system loops. Projects of the process control course emphasize implementation aspects such as sensors, signal conditioning and transmission, actuators and PID controller tuning. Projects of the digital control

G. Beauchamp-Baez; L. V. Melendez-Gonzalez

1998-01-01

157

Stormwater control measure (SCM) design standards to limit stream erosion for Piedmont North Carolina  

NASA Astrophysics Data System (ADS)

SummaryThis study evaluated the potential impacts of sub-bankfull flows produced by stormwater control measures (SCMs) on stream geomorphic stability. In part, design standards for SCMs include peak flow attenuation to maintain pre-development flow conditions to those of undeveloped watersheds or return urbanized, developed watersheds back to the pre-developed state. Most SCMs target lower frequency storms, usually the 2-and/or 10-year discharge events, but leave peak flows resulting from higher frequency storms uncontrolled. SCMs are possibly subjecting streams to longer and more frequent periods of erosion, increasing stream channel instability. The d65 substrate size, pattern, profile, and dimension of 33 reference stream cross-sections in Piedmont North Carolina were modeled using the continuous simulations program, SWMM, to develop (1) a unit critical discharge metric in L/s/ha, Q c = 0.0035( d65) 1.5048, (2) allowable annual erosional hour standard, Log(AAEH) = -1.26Log( d65) + 1.21, and (3) allowable volume of eroded bedload standard, Log(AV) = -0.64( Q c) - 1.52, for watersheds containing SCMs discharging into surface waters. The unit critical discharge represents a threshold that, once exceeded, incipient motion of the d65 particle can occur. These standards represented benchmarks of stable, naturally eroding reference streams. Ninety-four percent of the unit critical discharges were less than the 2-year 24-h event, indicating the necessity of controlling higher frequency sub-bankfull flows. The standards were applied to an urbanized watershed (one sub-catchment containing a structural SCM and two sub-catchments without) in Raleigh, North Carolina. The unit critical discharge metric appeared to adequately represent urbanized stream geomorphic processes for the sub-catchment undergoing urbanization (4.5% difference) but not for the mature urbanized sub-catchments (47.5% and 68.8% difference). Depending on the long-term management goal of the unstable stream, this metric is not applicable for all urbanized watersheds due to the discrepancy between the field and calculated unit critical discharges. Standards developed from urbanized reference streams could possibly better represent SCMs in urbanized watersheds. All three sub-catchments failed to meet the erosional standards demonstrating the ability of the standards to predict unstable geomorphic processes in streams. The addition of a detention SCM (wet pond), in the urbanized sub-catchment extended the duration of erosive flows from 37 to 87 h/ha/yr, but reduced the estimated volume of eroded bedload from 1.81 to 0.99 m 3/m/ha/yr when compared to uncontrolled urbanization (no wet pond). Alterations to the design of the wet pond, increased volume size and change in orifice diameter, were explored to see if erosional standards could be better met. This study demonstrated the effect of current SCM design standards on stream stability and why geomorphic processes of stream channels should be incorporated in SCM design standards.

Tillinghast, E. D.; Hunt, W. F.; Jennings, G. D.

2011-12-01

158

WATER EROSION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Water erosion is caused by the detachment and transport of soil by runoff, melting snow or ice, and irrigation. Excessive erosion could threaten the production of agricultural and forest products. Erosion may also impact water conveyance and storage structures, and contribute to pollution from land ...

159

Alginate controls heartburn in patients with erosive and nonerosive reflux disease  

PubMed Central

AIM: To evaluate the effect of a novel alginate-based compound, Faringel, in modifying reflux characteristics and controlling symptoms. METHODS: In this prospective, open-label study, 40 patients reporting heartburn and regurgitation with proven reflux disease (i.e., positive impedance-pH test/evidence of erosive esophagitis at upper endoscopy) underwent 2 h impedance-pH testing after eating a refluxogenic meal. They were studied for 1 h under basal conditions and 1 h after taking 10 mL Faringel. In both sessions, measurements were obtained in right lateral and supine decubitus positions. Patients also completed a validated questionnaire consisting of a 2-item 5-point (0-4) Likert scale and a 10-cm visual analogue scale (VAS) in order to evaluate the efficacy of Faringel in symptom relief. Tolerability of the treatment was assessed using a 6-point Likert scale ranging from very good (1) to very poor (6). RESULTS: Faringel decreased significantly (P < 0.001), in both the right lateral and supine decubitus positions, esophageal acid exposure time [median 10 (25th-75th percentil 6-16) vs 5.8 (4-10) and 16 (11-19) vs 7.5 (5-11), respectively] and acid refluxes [5 (3-8) vs 1 (1-1) and 6 (4-8) vs 2 (1-2), respectively], but increased significantly (P < 0.01) the number of nonacid reflux events compared with baseline [2 (1-3) vs 3 (2-5) and 3 (2-4) vs 6 (3-8), respectively]. Percentage of proximal migration decreased in both decubitus positions (60% vs 32% and 64% vs 35%, respectively; P < 0.001). Faringel was significantly effective in controlling heartburn, based on both the Likert scale [3.1 (range 1-4) vs 0.9 (0-2); P < 0.001] and VAS score [7.1 (3-9.8) vs 2 (0.1-4.8); P < 0.001], but it had less success against regurgitation, based on both the Likert scale [2.6 (1-4) vs 2.2 (1-4); P = not significant (NS)] and VAS score [5.6 (2-9.6) vs 3.9 (1-8.8); P = NS]. Overall, the tolerability of Faringel was very good 5 (2-6), with only two patients reporting modest adverse events (i.e., nausea and bloating). CONCLUSION: Our findings demonstrate that Faringel is well-tolerated and effective in reducing heartburn by modifying esophageal acid exposure time, number of acid refluxes and their proximal migration. PMID:22969201

Savarino, Edoardo; de Bortoli, Nicola; Zentilin, Patrizia; Martinucci, Irene; Bruzzone, Luca; Furnari, Manuele; Marchi, Santino; Savarino, Vincenzo

2012-01-01

160

Erosion Effects  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

The impact crater in this THEMIS image is a model illustration to the effects of erosion on Mars. The degraded crater rim and several landslides observed in crater walls is evidence to the mass wasting of materials. Layering in crater walls also suggests the presence of materials that erode at varying rates.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

Image information: VIS instrument. Latitude 31.6, Longitude 44.3 East (315.7 West). 19 meter/pixel resolution.

2003-01-01

161

Watershed management for erosion and sedimentation control Case Study: Goodwin Creek, Panola County, MS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Goodwin Creek watershed is located within the loessal hills of northern Mississippi, a region of high erosion risk and elevated watershed sediment yields. This manuscript combines a regional history of land management and conservation issues from the time of European settlement to present with a...

162

Toxicity of anionic polyacrylamide formulations when used for erosion control in agriculture  

Technology Transfer Automated Retrieval System (TEKTRAN)

Addition of anionic polyacrylamide (PAM) to agricultural irrigation water can dramatically reduce erosion of soils. However, the toxicity of PAM to aquatic life, while often claimed to be low, has not been thoroughly evaluated. Five PAM formulations, including two oil-based products, one water-based...

163

Evaluating Material Properties to Optimize Wood Strands for Wind Erosion Control  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wind erosion is a widespread problem in much of the western United States due to arid conditions and persistent winds. Fugitive dust from eroding land poses a risk to both environmental quality and human health. Since the advent of the Clean Air Act in 1971, ambient air quality standards have been ...

164

Integrated erosion control measures and environmental effects in rocky mountainous areas in northern China  

Microsoft Academic Search

Based on observations of runoff plots and field investigations of gully cross-sections, impacts of various soil and water conservation measures on runoff and sediment yield are analyzed for different rainfall conditions. The results show that antecedent rainfall and rainfall intensity are the main factors affecting the runoff and soil erosion processes. Rainfall events with antecedent rainfall can produce high runoff

Jijun HE; Qiangguo CAI; Guoqiang LI; Zhongke WANG

2010-01-01

165

Chronic erosion in Wissant Bay coast, northern France - Causes and trials of management projects  

NASA Astrophysics Data System (ADS)

Cape Gris Nez to the southwest and Cape Blanc Nez to the northeast limit's Wissant Bay. This extreme northern coast of France, facing the Dover Strait, is one of the most rapidly eroding sector of coast in France. Shoreline retreat has exceeded 250 m in the last fifty years in the central and western parts of the bay, while the eastern sector of the bay is now a zone of accretion, after being a sand-starved zone in the past, when the western sector was either stable or in accretion. The reasons for these changes are still not clear. They seem to involve interactions between a nearshore sand bank and the activity of current gyres related to the projecting headland of Cape Gris Nez, beach rotation processes and human activities, notably past aggregate extraction from the nearshore sand bank which acted hitherto as both a dissipater of incident storm wave energy and as a coastal sand source. The aim of this paper to contribute to the understanding of these long-term changes and investigate the mechanisms of this mildly embayed coast evolution. To this end, 10-years of topographic profile data throughout the bay were analysed and confronted with offshore wave data. This analysis complements a previous analytical effort that determined gross rates of annual shoreline retreat by time slices of several decades from the careful interpretation of long series of ortho-rectified aerial photographs. The overall data suggest chronic sand bleeding from the western sector of the beach and longshore transport to the east, within a framework of what appears to be an ongoing beach rotation process within a dominant longshore sediment transport cell between the headland of Cape Gris Nez and the bold chalk cliffs of Cape Blanc Nez. Retreat of the beach-dune barrier in the western sector of Wissant Bay poses a threat in the coming years as there is a likelihood of storm breaching of the narrow dune barrier. Face to this critical situation, a proper management strategy involving a good understanding and an integrated view of beach and coastal dynamics, as well as defence strategies covering not only the beaches but also the dunes and the nearshore zone must be applied. This can only be effectively done within the framework of the immediate implementation of Integrated Coastal Zone Management.

Sedrati, M.; Anthony, E. J.

2012-04-01

166

Holocene activity of an alpine debris-flow catchment: does climate control erosion rate variability?  

NASA Astrophysics Data System (ADS)

The Zielbach catchment is located in the central-eastern Italian Alps. It covers an area of ca. 40 km2 and is characterized by fluvial sediment transport along the main drainage basin, and by the supply of sediment through debris flows, derived from a ca. 10 km2 tributary catchment. A debris-flow database demonstrates that nowadays this latter tributary dominates the sediment budget of the entire Zielbach. In this study, we analyze modern and paleo-erosion rates of the catchment through the application of the cosmogenic nuclides technique. For modern erosion rate, samples of river-born sand were taken from the main river and tributaries along the entire drainage system, while paleo-erosion rates are calculated thanks to cores' samples, which were collected on the alluvial fan and which were likewise dated based on 14C measurements of organic matter. Results obtained from the modern drainage system reveal the spatial erosion rate variability that characterizes the catchment nowadays (values ranging from 2.6 to 0.15 mm/yr). This spatial pattern is characterized by a generally increasing trend of 10Be values where hillslope contributions predominate and by a decreasing concentration trend where sediment has been supplied by debris flows. Results obtained from the cores allow the reconstruction of the Zielbach Holocene evolution and the assignment of the climate role on the temporal erosion rate variability (values ranging between 21 and 0.43 mm/yr). 14C concentrations of organic material collected from the core material indicate a lowermost age of 10'000 yr at ca. 35 m depth. The sedimentary fabric of the deposits indicates that the fan is built up by alternation of alluvial and debris-flow deposits, where the latter ones dominate in volumes. The stratigraphic architecture also infers that alluvial deposits correspond to periods of low activity of the debris-flow catchment. Most important, however, paleo-erosion rates indicate a decreasing trend for the debris-flow activity from ca. 10'000 yr to the present, with values decreasing from ca. 21 to 0.8 mm/yr. During the same time span, the alluvial sediment supplied by the main catchment appears to have been steady, as indicated by a constant basin-averaged denudation rate of 0.45 mm/yr. The comparison of these results with the climatic history of the valley reveals that periods of high activity of the debris flow catchment (associated with higher 10Be-based erosion rates) correspond to periods of a wetter and cooler climate. In particular, the highest value (21 mm/yr) seems to be related to the late glacial phase, which presumably started after the LGM and terminated around 10'000 yr, while a reactivation of the debris-flow activity, with erosion rates around 1.0 mm/yr, corresponds to the Holocene climatic deterioration at ca. 3'500 yr B.P. The alluvial phase of the Zielbach catchment (erosion rate of ca. 0.43 mm/yr), marked by absent or lower debris-flow activity, seems to be related to the Holocene climatic optimum between 8'000 and 4'000 years ago.

Savi, S.; Norton, K. P.; Brardinoni, F.; Akçar, N.; Kubik, P.; Picotti, V.; Schlunegger, F.

2012-12-01

167

Radial Erosion  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

The ejecta surrounding the crater (off image to the left) in this image has undergone significant erosion by the wind. The wind has stripped the surface features from the ejecta and has started to winnow away the ejecta blanket. Near the margin of the ejecta the wind is eroding along a radial pattern -- taking advantage of radial emplacement. Note the steep margin of the ejecta blanket. Most, if not all, of the fine ejecta material has been removed and the wind in now working on the more massive continuous ejecta blanket.

Image information: VIS instrument. Latitude 12.5, Longitude 197.4 East (162.6 West). 37 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2005-01-01

168

ELKINS MINE DRAINAGE POLLUTION CONTROL DEMONSTRATION PROJECT  

EPA Science Inventory

In 1964 several federal agencies in cooperation with the State of West Virginia initiated a project to demonstrate methods to control the pollution from abandoned underground and surface mines in the Roaring Creek-Grassy Run Watersheds near Elkins, West Virginia. The Roaring Cree...

169

Evaluation of the Wind Erosion Prediction System (WEPS) erosion submodel on cropland fields  

Microsoft Academic Search

This study represents part of a project by the Global Change and Terrestrial Ecosystem Soil Erosion Network to validate wind erosion models. Soil loss measurements from 46 storm events from eroding fields in six states were compared to predictions from the Wind Erosion Prediction System (WEPS) erosion submodel. The field data were collected from small (2.5 ha), circular, cropland fields

Lawrence J. Hagen

2004-01-01

170

Irrigation: Erosion  

Technology Transfer Automated Retrieval System (TEKTRAN)

Irrigation is essential for global food production. However, irrigation erosion can limit the ability of irrigation systems to reliably produce food and fiber in the future. The factors affecting soil erosion from irrigation are the same as rainfall—water detaches and transports sediment. However, t...

171

Erosion can be a problem in many airfield areas. Erosion and sedimentation affect  

E-print Network

Erosion can be a problem in many airfield areas. Erosion and sedimentation affect local water. Effective erosion control requires an integrated approach that takes into account government regu- lations and erosion control methods (see examples in Figs. 1 and 2). This article outlines several considerations

Minnesota, University of

172

Assessment of Soil Moisture and Fixatives Performance in Controlling Wind Erosion of Contaminated Soil at the Hanford Site  

SciTech Connect

During the remediation of burial grounds at the US Department of Energy's (DOE's) Hanford Site in Washington State, the dispersion of contaminated soil particles and dust is an issue that is faced by site workers on a daily basis. This contamination issue is even more of a concern when one takes into account the semi-arid characteristics of the region where the site is located. To mitigate this problem, workers at the site use a variety of engineered methods to minimize the dispersion of contaminated soil and dust particles. Once such methods is the use of water and/or suppression agents (fixatives) that stabilizes the soil prior to soil excavation, segregation, and removal activities. A primary contributor to the dispersion of contaminated soil and dust is wind soil erosion. The erosion process occurs when the wind speed exceeds a certain threshold value (threshold shear velocity), which depends on a number of factors including wind force loading, particle size, surface soil moisture, and the geometry of the soil. Thus under these circumstances the mobility of contaminated soil and generation and dispersion of particulate matter are significantly influenced by these parameters. Wind tunnel experiments were conducted at the Florida International University's Applied Research Center (FIU-ARC) to evaluate the effectiveness of three commercially available fixatives in controlling the mobility of soil particles on soil mounds when exposed to varying wind forces. The fixatives tested included: (1) a calcium chloride solution; (2) a petroleum hydrocarbon emulsion; and 3) a synthetic organic. As an initial step, approximately 500 lbs of uncontaminated soil was obtained from the Hanford Reservation in Washington State. Soil samples were placed in an open-loop, low speed wind tunnel and exposed to wind forces ranging from 10 to 30 miles per hour (mph). Wind erosion controlling capabilities of commercially available fixatives and soil moisture were tested at a laboratory scale. Soil samples with varying moisture (W/W %) content and soil samples treated with fixatives, selected from a wide range of commercially available products, were exposed to a wind speeds ranging from 10 - 30 miles per hour (MPH). During these experiments, amount of soil displaced due to the wind forces, the amount of airborne particulates generated, and the moisture loss were measured to better understand the performance of selected fixatives and soil moisture. Results obtained during the study showed that there is a significant reduction in wind erosion and airborne particles generation by increasing the soil moisture for the velocities tested. Similar trend was observed when the soil samples treated with fixatives were exposed to the same range of velocities (10 - 30 MPH). (authors)

Lagos, L.E.; Gudavalli, R.K. [Applied Research Center, Florida International Univ., Miami, FL (United States)

2008-07-01

173

CRCHD SPN Project: Pacific Islander Cancer Control Network  

Cancer.gov

CRCHD SPN Project: Pacific Islander Cancer Control Network  Back to CRCHD Completed Research SPN Project Listing Pacific Islander Cancer Control Network Pacific Islander Cancer Control Network INVESTIGATOR: Allan Hubbell, M.D. INSTITUTION: Pacific

174

Effects of erosion control structures along a portion of the northern Chesapeake Bay shoreline  

USGS Publications Warehouse

A 6.500-meter reach of western Chesapeake Bay shoreline (lower Mayo Peninsula) lost about 1.1??106 cubic meters of sediment (equivalent to 170 cubic meters lost per meter of shoreline) between 1846 and 1932, when the first aerial photographs show the shoreline already substantially protected by a system of groins and intermittent bulkheading. These structures have eliminated the fastland as a source of erodable material, and have starved the supply of sand for littoral drift, thus limiting the extent of the beaches to the remaining groin fields. Volumes of sediment involved in these impacts are small in the overall sediment budget. Bulkheads produce no deficit in the budget since scouring of the beaches on their seaward sides makes up for the decreased erosion of protected fastland. Groins trap little of the potential littoral drift (computed to be about 104 cubic meters per meter of shoreline per year). The sand supply in the remaining beaches is nearly equivalent to the annual loss of sediment from the entire shoreline system due to the long-term rate of erosion of the shoreline and nearshore between 1846 and 1932. ?? 1981 Springer-Verlag New York Inc.

Zabawa, C.F.; Kerhin, R.T.; Bayley, S.

1981-01-01

175

[Optimization of shelterbelt distribution for the gully erosion control of cultivated slope land in rolling hill black soil region of Northeast China].  

PubMed

Shelterbelt system is one of the main components of cultivated slope land in rolling hill black soil region of Northeast China, which plays an important role in the control of gully erosion. Based on the Quickbird high-resolution remote sensing image and the digital elevation model (DEM), and combining with field survey data, this paper analyzed the effects of shelterbelt system in a small watershed of rolling hill black soil region in Heshan Farm of Heilongjiang Province on the control of gully erosion in the cultivated slope land, and put forward an optimized scheme for gully erosion control based on the features of gully erosion in the cultivated slope land and their relations with the distribution of the shelterbelt system. In the study area, the current distribution of the shelterbelt system promoted the occurrence and development of shallow gully and gully directly and indirectly. The proposed scheme for optimizing the distribution of the present shelterbelts included the adjustment of the direction of the shelterbelt perpendicular to the aspect of slope, the enhancement of the maintenance and regeneration of the shelterbelts to reduce the gaps of the shelterbelts, the increase of the shelterbelt number, and the decrease of the distances between shelterbelts. A method for calculating the shelterbelt number and the distances between the shelterbelts was also given. This study could provide scientific basis for the gully erosion control and the shelterbelts programming in the cultivated slope land of rolling hill black soil region. PMID:22803452

Su, Zi-Long; Cui, Ming; Fan, Hao-Ming

2012-04-01

176

Optimal disturbance rejection in missile autopilot design using projective controls  

Microsoft Academic Search

A projective controls approach is used to design a normal acceleration command missile autopilot. Projective controls are used to retain the eigenstructure of an H? optimal state feedback controller using a low-order output feedback compensator, but retaining the performance, robustness, and disturbance attenuation properties of the state feedback design. A free parameter matrix used in the projective control design is

Kevin A. Wise; Tam Nguyen

1992-01-01

177

Optimal disturbance rejection in missile autopilot design using projective controls  

Microsoft Academic Search

A projective control approach used to design a normal acceleration command missile autopilot is presented. Projective controls are used to retain the eigenstructure of an H? optimal state feedback controller using a low-order output feedback compensator and to retain the performance, robustness, and disturbance attenuation properties of the state feedback design. A free parameter matrix used in the projective control

Kevin A. Wise; Tam Nguyen

1991-01-01

178

Couplages Tectonique -Erosion Berger, 2008  

E-print Network

Couplages Tectonique -Erosion Berger, 2008 #12;Couplages Tectonique -Erosion #12;Couplages Tectonique -Erosion #12;Couplages Tectonique -Erosion #12;Couplages Tectonique -Erosion #12;Couplages Tectonique -Erosion #12;Couplages Tectonique -Erosion #12;Couplages Tectonique -Erosion #12;Couplages

Demouchy, Sylvie

179

The spatiotemporal control of erosion and molecular release from micropatterned poly(ethylene glycol)-based hydrogel.  

PubMed

Hydrogels have been extensively studied as a carrier of various hydrophilic molecular compounds and cells for local delivery and subsequent controlled release. One of key design parameters in the hydrogel assembly is an ability to control spatiotemporal gel degradation, in order to tailor release rates of multiple drugs and also regulate phenotypic activities of co-cultured cells. To achieve this goal, this study presents a simple but innovative implantable, microfabricated hydrogel patch that undergoes micropatterned surface erosion at controlled rates and subsequently discharges two molecular compounds of interests at desired rates. This device was prepared by first fabricating a non-degradable poly(ethylene glycol) dimethacrylate (PEGDMA) hydrogel patch containing micro-pockets of controlled spacing and subsequently filling micro-pockets with a hydrogel of poly(ethylene imine) (PEI) and PEG diacrylate (PEGDA) that was tailored to degrade at controlled rates. Separate incorporation of vascular endothelial growth factor (VEGF)121 and VEGF165, known to orchestrate vascular development, into the PEI-PEGDA gel and PEGDMA hydrogel resulted in enhanced neovascularization at the implantation sites due to bimodal, sequential release of two VEGF isoforms. We believe that the hydrogel patch fabricated in this study will be highly useful to better understand a broad array of complex biological processes and also improve the efficacy of molecular cargos in varied applications. PMID:23886733

Yonet-Tanyeri, Nihan; Rich, Max H; Lee, Minkyung; Lai, Mei-Hsiu; Jeong, Jae Hyun; DeVolder, Ross J; Kong, Hyunjoon

2013-11-01

180

In-situ measurements of alloy oxidation/corrosion/erosion using a video camera and proximity sensor with microcomputer control  

NASA Technical Reports Server (NTRS)

Two noncontacting and nondestructive, remotely controlled methods of measuring the progress of oxidation/corrosion/erosion of metal alloys, exposed to flame test conditions, are described. The external diameter of a sample under test in a flame was measured by a video camera width measurement system. An eddy current proximity probe system, for measurements outside of the flame, was also developed and tested. The two techniques were applied to the measurement of the oxidation of 304 stainless steel at 910 C using a Mach 0.3 flame. The eddy current probe system yielded a recession rate of 0.41 mils diameter loss per hour and the video system gave 0.27.

Deadmore, D. L.

1984-01-01

181

Controls and Electronics in the LEBIT Project  

NASA Astrophysics Data System (ADS)

The LEBIT project at the NSCL is an experiment under construction that will accept a high-energy beam from the coupled cyclotron and convert it to a low-energy, low-emittance beam. This low-energy beam will be used in a variety of experiments, including precision mass measurements of exotic nuclei. The experiment contains a gas-stopping cell followed by an ion transport and trapping system. One particular section consists of an ion trap that accumulates incoming ions, cools them, and releases them as ion bunches. Following the buncher is an electrostatic deflector that serves to steer the ions as they leave this trap. Although the control for the deflector is at ground, the deflector needs be raised to an average 2kV potential. Relative to this potential, offsets are applied to the horizontal and vertical steering plates, in order to achieve beam steering. This summer, an electronic board was worked on to accomplish this. The main components of the board include DC/DC converter and high-voltage isolation amplifiers. Because of the complexity of the LEBIT project, all instruments will be controlled through computers. One programming interface currently being used is LabView. Programs have been designed to control the Keithley 2000-20 Multimeter and the Keithley 6514 Electrometer. These instruments will serve to measure voltage and small beam currents.

Janus, Elizabeth

2002-10-01

182

Measurement of the fluorescence of crop residues: A tool for controlling soil erosion  

NASA Technical Reports Server (NTRS)

Management of crop residues, the portion of a crop left in the field after harvest, is an important conservation practice for minimizing soil erosion and for improving water quality. Quantification of crop residue cover is required to evaluate the effectiveness of conservation tillage practices. Methods are needed to quantify residue cover that are rapid, accurate, and objective. The fluorescence of crop residue was found to be a broadband phenomenon with emission maxima at 420 to 495 nm for excitations of 350 to 420 nm. Soils had low intensity broadband emissions over the 400 to 690 nm region for excitations of 300 to 600 nm. The range of relative fluorescence intensities for the crop residues was much greater than the fluorescence observed of the soils. As the crop residues decompose their blue fluorescence values approach the fluorescence of the soil. Fluorescence techniques are concluded to be less ambiguous and better suited for discriminating crop residues and soils than reflectance methods. If properly implemented, fluorescence techniques can be used to quantify, not only crop residue cover, but also photosynthetic efficiency in the field.

Daughtry, C. S. T.; Mcmurtrey, J. E., III; Chappelle, E. W.; Hunter, W. J.

1994-01-01

183

77 FR 47063 - Notice of Availability of Draft Revisions; Upland Erosion Control, Revegetation, and Maintenance...  

Federal Register 2010, 2011, 2012, 2013

...Revegetation, and Maintenance Plan; Wetland and Waterbody Construction and Mitigation...Revegetation, and Maintenance Plan (Plan) and Wetland and Waterbody Construction and Mitigation...duration of project-related disturbance on wetlands and waterbodies. Attached to this...

2012-08-07

184

Final Report Project Title: Quantification of Runoff and Erosion on Semi-arid Grasslands following a Wildfire JFSP Project No: 03-2-3-11  

Microsoft Academic Search

Summary Background • The objectives of the study were to 1. quantify the effects of a wildfire on runoff and erosion and 2. parameterize the USFS ERMiT model for two ungrazed desert grassland sites in southeastern Arizona. • Rainfall simulator experiments were conducted on the two sites immediately after a wildfire and for subsequent years to document the recovery process.

J J Stone; G B Paige; D P Guertin; G Gottfried; S. Gunzel

185

Reduction of Soil Erosion on Forest Roads  

Microsoft Academic Search

Results of onsite erosion control work from across the United States provide estimates of the amount of erosion reduction on forest roads from various treatments. Supplementary information includes the effects of slope gradient, soil characteristics, and ground cover. Estimates of sediment travel below fillslopes can be made, together with the combined effect of erosion control treatments of the running surface,

Burroughs Jr. Edward R; John G. King

1989-01-01

186

A Statistical Project Control Tool for Engineering Managers  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the use of a Statistical Project Control Tool (SPCT) for managing engineering projects. A literature review pointed to a definition of project success, (i.e., A project is successful when the cost, schedule, technical performance, and quality satisfy the customer.) The literature review also pointed to project success factors, and traditional project control tools, and performance measures that are detailed in the report. The essential problem is that with resources becoming more limited, and an increasing number or projects, project failure is increasing, there is a limitation of existing methods and systematic methods are required. The objective of the work is to provide a new statistical project control tool for project managers. Graphs using the SPCT method plotting results of 3 successful projects and 3 failed projects are reviewed, with success and failure being defined by the owner.

Bauch, Garland T.

2001-01-01

187

Manual Controls for High-Dimensional Data Projections  

Microsoft Academic Search

Projections of high-dimensional data onto low-dimensional subspaces provide insightful views for understanding multivariate relationships. This article discusses how to manually control the variable contributions to the projection. The user has control of the way a particular variable contributes to the viewed projection and can interactively adjust the variable's contribution. These manual controls complement the automatic views provided by a grand

Dianne Cook; Andreas Buja

1997-01-01

188

Controls on coastal dune morphology, shoreline erosion and barrier island response to extreme storms  

USGS Publications Warehouse

The response of a barrier island to an extreme storm depends in part on the surge elevation relative to the height and extent of the foredunes which can exhibit considerable variability alongshore. While it is recognized that alongshore variations in dune height and width direct barrier island response to storm surge, the underlying causes of the alongshore variation remain poorly understood. This study examines the alongshore variation in dune morphology along a 11??km stretch of Santa Rosa Island in northwest Florida and relates the variation in morphology to the response of the island during Hurricane Ivan and historic and storm-related rates of shoreline erosion. The morphology of the foredune and backbarrier dunes was characterized before and after Hurricane Ivan using Empirical Orthogonal Function (EOF) analysis and related through Canonical Correlation Analysis (CCA). The height and extent of the foredune, and the presence and relative location of the backbarrier dunes, varied alongshore at discrete length scales (of ~ 750, 1450 and 4550??m) that are statistically significant at the 95% confidence level. Cospectral analysis suggests that the variation in dune morphology is correlated with transverse ridges on the inner-shelf, the backbarrier cuspate headlands, and the historical and storm-related trends in shoreline change. Sections of the coast with little to no dune development before Hurricane Ivan were observed in the narrowest portions of the island (between headlands), west of the transverse ridges. Overwash penetration tended to be larger in these areas and island breaching was common, leaving the surface close to the watertable and covered by a lag of shell and gravel. In contrast, large foredunes and the backbarrier dunes were observed at the widest sections of the island (the cuspate headlands) and at crest of the transverse ridges. Due to the large dunes and the presence of the backbarrier dunes, these areas experienced less overwash penetration and most of the sediment from the beachface and dunes was deposited within the upper-shoreface. It is argued that this sediment is returned to the beachface through nearshore bar migration following the storm and that the areas with larger foredunes and backbarrier dunes have smaller rates of historical shoreline erosion compared to areas with smaller dunes and greater transfer of sediment to the washover terrace. Since the recovery of the dunes will vary depending on the availability of sediment from the washover and beachface, it is further argued that the alongshore pattern of dune morphology and the response of the island to the next extreme storm is forced by the transverse ridges and island width through alongshore variations in storm surge and overwash gradients respectively. These findings may be particularly important for coastal managers involved in the repair and rebuilding of coastal infrastructure that was damaged or destroyed during Hurricane Ivan. ?? 2008 Elsevier B.V. All rights reserved.

Houser, C.; Hapke, C.; Hamilton, S.

2008-01-01

189

Rainfall Energy Variability across Pennsylvania: Impacts on Construction Site Erosion Control Practices Aigul Allison and Shirley E. Clark, Ph.D., P.E., D WRE  

E-print Network

Rainfall Energy Variability across Pennsylvania: Impacts on Construction Site Erosion Control Engineering Program, Middletown, PA INTRODUCTION Construction sediment loss causes water pollution, clogs's Construction Waiver Program] and 2 [updated by USDA]). The calculations excluded rains less than 0.5 inches

Clark, Shirley E.

190

Greenidge Multi-Pollutant Control Project  

SciTech Connect

The Greenidge Multi-Pollutant Control Project was conducted as part of the U.S. Department of Energy's Power Plant Improvement Initiative to demonstrate an innovative combination of air pollution control technologies that can cost-effectively reduce emissions of SO{sub 2}, NO{sub x}, Hg, acid gases (SO{sub 3}, HCl, and HF), and particulate matter from smaller coal-fired electric generating units (EGUs). There are about 400 units in the United States with capacities of 50-300 MW that currently are not equipped with selective catalytic reduction (SCR), flue gas desulfurization (FGD), or mercury control systems. Many of these units, which collectively represent more than 55 GW of installed capacity, are difficult to retrofit for deep emission reductions because of space constraints and unfavorable economies of scale, making them increasingly vulnerable to retirement or fuel switching in the face of progressively more stringent environmental regulations. The Greenidge Project sought to confirm the commercial readiness of an emissions control system that is specifically designed to meet the environmental compliance requirements of these smaller coal-fired EGUs by offering a combination of deep emission reductions, low capital costs, small space requirements, applicability to high-sulfur coals, mechanical simplicity, and operational flexibility. The multi-pollutant control system includes a NO{sub x}OUT CASCADE{reg_sign} hybrid selective non-catalytic reduction (SNCR)/in-duct SCR system for NO{sub x} control and a Turbosorp{reg_sign} circulating fluidized bed dry scrubbing system (with a new baghouse) for SO{sub 2}, SO{sub 3}, HCl, HF, and particulate matter control. Mercury removal is provided as a co-benefit of the in-duct SCR, dry scrubber, and baghouse, and by injection of activated carbon upstream of the scrubber, if required. The multi-pollutant control system was installed and tested on the 107-MW{sub e}, 1953-vintage AES Greenidge Unit 4 by a team including CONSOL Energy Inc. as prime contractor, AES Greenidge LLC as host site owner, and Babcock Power Environmental Inc. as engineering, procurement, and construction contractor. About 44% of the funding for the project was provided by the U.S. Department of Energy, through its National Energy Technology Laboratory, and the remaining 56% was provided by AES Greenidge. Project goals included reducing high-load NO{sub x} emissions to {le} 0.10 lb/mmBtu; reducing SO{sub 2}, SO{sub 3}, HCl, and HF emissions by at least 95%; and reducing Hg emissions by at least 90% while the unit fired 2-4% sulfur eastern U.S. bituminous coal and co-fired up to 10% biomass. This report details the final results from the project. The multi-pollutant control system was constructed in 2006, with a total plant cost of $349/kW and a footprint of 0.4 acre - both substantially less than would have been required to retrofit AES Greenidge Unit 4 with a conventional SCR and wet scrubber. Start-up of the multi-pollutant control system was completed in March 2007, and the performance of the system was then evaluated over an approximately 18-month period of commercial operation. Guarantee tests conducted in March-June 2007 demonstrated attainment of all of the emission reduction goals listed above. Additional tests completed throughout the performance evaluation period showed 96% SO{sub 2} removal, 98% mercury removal (with no activated carbon injection), 95% SO{sub 3} removal, and 97% HCl removal during longer-term operation. Greater than 95% SO{sub 2} removal efficiency was observed even when the unit fired high-sulfur coals containing up to 4.8 lb SO{sub 2}/mmBtu. Particulate matter emissions were reduced by more than 98% relative to the emission rate observed prior to installation of the technology. The performance of the hybrid SNCR/SCR system was affected by problems with large particle ash, ammonia slip, and nonideal combustion characteristics, and high-load NO{sub x} emissions averaged 0.14 lb/mmBtu during long-term operation. Nevertheless, the system has reduced the unit's overall NO{sub x} emiss

Daniel Connell

2008-10-18

191

Modeling the air traffic controller's cognitive projection process  

E-print Network

Cognitive projection enables the operator of a supervisory control system, such as air traffic control, to use predicted future behavior of the system to make decisions about if and how to control the system. New procedures ...

Reynolds, Hayley J. Davison (Hayley Jaye Davison)

2006-01-01

192

Using soil erosion models for global change studies  

SciTech Connect

Future changes in climate and atmospheric carbon dioxide concentration will change the hydrologic cycle, affecting important soil-plant-water interactions, which in turn affect soil erosion rates. This report describes major soil erosion models which include Environmental Policy Integrated Climate (EPIC); Water Erosion Prediction Project (WEPP); Wind Erosion Prediction System (WEPS); and the Climate generator Model (CLIGEN).

Williams, J.; King, K. [Texas Agricultural Experiment Station, Temple, TX (United States); Nearing, M. [USDA/ARS, West Lafayette, IN (United States)] [and others

1996-09-01

193

Chapter 1. OVERVIEW OF THE WEPP EROSION PREDICTION MODEL  

Microsoft Academic Search

The USDA - Water Erosion Prediction Project (WEPP) model represents a new erosion prediction technology based on fundamentals of stochastic weather generation, infiltration theory, hydrology, soil physics, plant science, hydraulics, and erosion mechanics. The hillslope or landscape profile application of the model provides major advantages over existing erosion prediction technology. The most notable advantages include capabilities for estimating spatial and

D. C. Flanagan; J. C. Ascough; A. D. Nicks; M. A. Nearing; J. M. Laflen

194

TRUCKEE MEADOWS FLOOD CONTROL PROJECT, NEVADA 17 December 2013  

E-print Network

the Pre-construction Engineering and Design phase when changes in real estate costs made the projectTRUCKEE MEADOWS FLOOD CONTROL PROJECT, NEVADA 17 December 2013 ABSTRACT: The Truckee Meadows Flood Control Project was authorized under the Water Resources Development Act 1988, but was deferred during

US Army Corps of Engineers

195

Environmental Impact Statement Truckee Meadows Flood Control Project  

E-print Network

-construction Engineering and Design (PED) phase when changes in real estate costs made the project economically infeasibleDRAFT Environmental Impact Statement for the Truckee Meadows Flood Control Project Nevada General Control Project Nevada General Reevaluation Report Volume I ­ Draft Environmental Impact Statement

US Army Corps of Engineers

196

Floodplain Assessment for the Proposed Engineered Erosion Controls at TA-72 in Lower Sandia Canyon, Los Alamos National Laboratory  

SciTech Connect

Los Alamos National Laboratory (LANL) is preparing to implement engineering controls in Sandia Canyon at Technical Area (TA) 72. Los Alamos National Security (LANS) biologists conducted a floodplain determination and this project is located within a 100-year floodplain. The proposed project is to rehabilitate the degraded channel in lower Sandia Canyon where it crosses through the outdoor firing range at TA-72 to limit the loss of sediment and dissipate floodwater leaving LANL property (Figure 1). The proposed construction of these engineered controls is part of the New Mexico Environment Department's (NMED) approved LANL Individual Storm Water Permit. The purpose of this project is to install storm water controls at Sandia Watershed Site Monitoring Area 6 (S-SMA-6). Storm water controls will be designed and installed to meet the requirements of NPDES Permit No. NM0030759, commonly referred to as the LANL Individual Storm Water Permit (IP). The storm water control measures address storm water mitigation for the area within the boundary of Area of Concern (AOC) 72-001. This action meets the requirements of the IP for S-SMA-6 for storm water controls by a combination of: preventing exposure of upstream storm water and storm water generated within the channel to the AOC and totally retaining storm water falling outside the channel but within the AOC.

Hathcock, Charles D. [Los Alamos National Laboratory

2012-08-27

197

Erosion in Rivers  

NSDL National Science Digital Library

Students learn about water erosion through an experimental process in which small-scale buildings are placed along a simulated riverbank to experience a range of flooding conditions. They learn how soil conditions are important to the stability or failure of civil engineering projects and how a river's turns and bends (curvature, sinuosity) make a difference in the likelihood of erosion. They make model buildings either with a 3D printer or with LEGO® pieces and then see how their designs and riverbank placements are impacted by slow (laminar) and fast (turbulent) water flow over the soil. Students make predictions, observations and conclusions about the stability of their model houses, and develop ideas for how to mitigate damage in civil engineering projects.

AMPS GK-12 Program,

198

Postfire Seeding for Erosion Control: Effectiveness and Impacts on Native Plant Communities  

Microsoft Academic Search

Large, high-severity wildfires remove vegetation cover and expose mineral soil, ofen causing ero- sion and runoff during postfire rain events to increase dramatically. Land-management agencies in the United States are required to assess site conditions after wildfire and, where necessary, implement emergency water- shed rehabilitation measures to help stabilize soil; control movement of water, sediment, and debris; prevent permanent impairment

JAN L. BEYERS

2004-01-01

199

Erosion and Sediment Damages and Economic Impacts of Potential 208 Controls: A Summary of Five Watershed Studies in Texas  

E-print Network

This report summarizes results of economic analyses of erosion and sedimentation in five agricultural watersheds in Texas (see fig. 1). Economic analyses of the study areas considered both the on-farm economics of soil conservation and the economic...

Taylor, C. R.; Reneau, D. R.; Harris, B. L.

200

Predicting postfire erosion and mitigation effectiveness with a web-based probabilistic erosion model  

Microsoft Academic Search

The decision of where, when, and how to apply the most effective postfire erosion mitigation treatments requires land managers to assess the risk of damaging runoff and erosion events occurring after a fire. To meet this challenge, the Erosion Risk Management Tool (ERMiT) was developed. ERMiT is a web-based application that uses the Water Erosion Prediction Project (WEPP) technology to

P. R. Robichaud; W. J. Elliot; F. B. Pierson; D. E. Hall; C. A. Moffet

2007-01-01

201

OPTIMAL CONTROL OF PROJECTS BASED ON KALMAN FILTER APPROACH FOR TRACKING & FORECASTING THE PROJECT PERFORMANCE  

E-print Network

to follow the original schedule or plan, inadvertently increasing the overall project cost. Many deterministic project control methods have been proposed by various researchers for calculating optimal resource schedules considering the time-cost as well...

Bondugula, Srikant

2010-07-14

202

Application of video-cameras for quality control and sampling optimisation of hydrological and erosion measurements in a catchment  

NASA Astrophysics Data System (ADS)

Long term soil erosion studies imply substantial efforts, particularly when there is the need to maintain continuous measurements. There are high costs associated to maintenance of field equipment keeping and quality control of data collection. Energy supply and/or electronic failures, vandalism and burglary are common causes of gaps in datasets, reducing their reach in many cases. In this work, a system of three video-cameras, a recorder and a transmission modem (3G technology) has been set up in a gauging station where rainfall, runoff flow and sediment concentration are monitored. The gauging station is located in the outlet of an olive orchard catchment of 6.4 ha. Rainfall is measured with one automatic raingauge that records intensity at one minute intervals. The discharge is measured by a flume of critical flow depth, where the water is recorded by an ultrasonic sensor. When the water level rises to a predetermined level, the automatic sampler turns on and fills a bottle at different intervals according to a program depending on the antecedent precipitation. A data logger controls the instruments' functions and records the data. The purpose of the video-camera system is to improve the quality of the dataset by i) the visual analysis of the measurement conditions of flow into the flume; ii) the optimisation of the sampling programs. The cameras are positioned to record the flow at the approximation and the gorge of the flume. In order to contrast the values of ultrasonic sensor, there is a third camera recording the flow level close to a measure tape. This system is activated when the ultrasonic sensor detects a height threshold, equivalent to an electric intensity level. Thus, only when there is enough flow, video-cameras record the event. This simplifies post-processing and reduces the cost of download of recordings. The preliminary contrast analysis will be presented as well as the main improvements in the sample program.

Lora-Millán, Julio S.; Taguas, Encarnacion V.; Gomez, Jose A.; Perez, Rafael

2014-05-01

203

Effect of erosion-control structures on sediment and nutrient transport, Edgewood Creek drainage, Lake Tahoe basin, Nevada, 1981-83  

USGS Publications Warehouse

Three sites in the Edgewood Creek basin with a combined drainage area of about 1.2 sq mi were selected to assess the effect of erosion-control structures along Nevada State Highway 207, on sediment and nutrient transport. The flow at site one is thought to have been largely unaffected by urban development, and was completely unaffected by erosion control structures. The flow at site two was from a basin affected by urban development and erosion control structures. Site three was downstream from the confluence of streams measured at sites one and two. Most data on streamflow and water quality were collected between June 1981 and May 1983 to assess the hydrologic characteristics of the three sites. As a result of the erosion control structures, mean annual concentrations of total sediment were reduced from about 24,000 to about 410 mg/l at site two and from about 1,900 to about 190 ml/l at site three. Sediment loads were reduced from about 240 to about 10 tons/year at site two and from about 550 to about 110 tons/year at site three. At site one, in contrast, mean concentrations and loads remained low throughout the study period. At site two, sediment particle size changed from predominately coarse prior to construction, to predominately fine thereafter; at site three, it changed from about half coarse sediments to predominately fine. Mean concentration and loads of total iron also were significantly reduced after construction at sites two and three, whereas mean concentrations of nitrogen and phosphorus species did not change appreciably. (Author 's abstract)

Garcia, K.T.

1988-01-01

204

Erosion resistance of irrigated soils in the republic of Azerbaijan  

NASA Astrophysics Data System (ADS)

It was found that the average size of water-stable aggregates in irrigated soils varies in the range 0.23-2.0 mm, and the eroding flow velocity is 0.03-0.12 m/s. A five-point scale was used for assessing erosion resistance, predicting irrigation erosion, and developing erosion control measures on irrigated soils. According to this system, gray-brown soils and light sierozems were classified as the least erosion-resistant, sierozemic and meadow-sierozemic soils as low erosion-resistant, gray-cinnamonic soils as moderately erosion-resistant, mountain gray-cinnamonic soils as highly erosion-resistant, and steppe mountain cinnamonic soils as very highly erosion-resistant ones. The determination of the erosion resistance of soils is of great importance for assessing the erosion-resistance potential of irrigated areas and developing erosion control measures.

Babaev, M. P.; Gurbanov, E. A.

2010-12-01

205

Coprates Erosion  

NASA Technical Reports Server (NTRS)

4 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows layered, light-toned, sedimentary rocks that have been exposed by erosion in Coprates Chasma, one of the many chasms which comprise the Valles Marineris trough system on Mars.

Location near: 13.1oS, 65.0oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

2006-01-01

206

Self-Correcting HVAC Controls Project Final Report  

SciTech Connect

This document represents the final project report for the Self-Correcting Heating, Ventilating and Air-Conditioning (HVAC) Controls Project jointly funded by Bonneville Power Administration (BPA) and the U.S. Department of Energy (DOE) Building Technologies Program (BTP). The project, initiated in October 2008, focused on exploratory initial development of self-correcting controls for selected HVAC components in air handlers. This report, along with the companion report documenting the algorithms developed, Self-Correcting HVAC Controls: Algorithms for Sensors and Dampers in Air-Handling Units (Fernandez et al. 2009), document the work performed and results of this project.

Fernandez, Nicholas; Brambley, Michael R.; Katipamula, Srinivas; Cho, Heejin; Goddard, James K.; Dinh, Liem H.

2010-01-04

207

Commonalities in WEPP and WEPS and efforts towards a single erosion process model  

Microsoft Academic Search

Since the late 1980's, the Agricultural Research Service (ARS) of the United States Department of Agriculture (USDA) has been developing process-based erosion models to predict water erosion and wind erosion. During much of that time, the development efforts of the Water Erosion Prediction Project (WEPP) and the Wind Erosion Prediction System (WEPS) were independent of each other. However, many of

S. M. Visser; D. C. Flanagan

2003-01-01

208

Measurement of soil water erosion in Africa: the potential support provided by nuclear techniques  

NASA Astrophysics Data System (ADS)

Conservation of soil and water resources has become a major agronomic and environmental concern. Degradation phenomena, such as erosion, desertification and salinization affect 65% of soils worldwide. Soil degradation is currently affecting 1.9 billion hectares and is increasing at a rate of 5 to 7 million hectares each year. Almost 50% of 133 million ha degraded soils by overexploitation are located in Africa. The degradation of arable lands affects especially arid areas with poor vegetation cover and tropical areas with high intensity rainfall. Water erosion is by far the most common type of land degradation in Africa. Accelerated erosion decreases soil productivity, increases sedimentation and is related to environmental pollution problems in agro-ecosystems. To control soil erosion there is a need to assess the impact of major land use and the effectiveness of specific soil conservation technologies using various approaches. Effective erosion control starts with the knowledge of soil erosion rates and mechanisms. In Africa, various research projects on water erosion have been implemented involving different conventional techniques such as remote sensing, morphometric investigation, sediment transport models and sediment loading measurements, runoff plots and rainfall erosivity measurements. However, only limited quantitative data on erosion and sedimentation magnitude under African agroenvironmental condition are available. Traditional monitoring and modeling techniques for soil water erosion require many parameters and years of measurements of (inter-annual and mid-term) climatic variability and cropping practices. Conventional erosion and sedimentation methods are limited to provide mid-term trends in soil erosion, however fallout radionuclides (FRN) - e.g. 137-Cs, 210-Pb and 7-Be - have proven to be very powerful tools to trace soil erosion and sedimentation within the landscape from plot to basin scale. FRN techniques allow the estimation of short and medium-term rates of soil redistribution integrating land use and climatic variability. FRN can be used to obtain average soil redistribution figures for time scales ranging from single events to many years of erosion processes, while direct erosion measurements are related to single rainfall events or rather short periods of time (e.g. erosion plots). FRN methodologies integrate all processes involving soil particle movements and allow quantification of soil loss and deposition associated with sheet erosion, which is difficult to assess using other conventional approaches. Sampling of individual points allows spatially distributed information on rates and patterns of soil redistribution. Also, one of the main advantages of the FRN is that time-consuming, costly maintenance, long-term monitoring programme and installations required by non isotopic and conventional methods can be avoided. Soil sampling can be completed in a short time and the site disturbance during sampling is minimal and does not interfere with seeding and cultivation operations. Since radionuclide-based measurements also provide information on the spatial distribution of erosion/sedimentation rates, they can be used to validate the results of distributed soil erosion models. The main purpose of this contribution is to present a synthetic overview of the usefulness in using nuclear techniques in Africa to investigate medium and short term soil erosion and sedimentation processes. Also, the advantages and limitations in using the FRN (137-Cs, 210-Pb and 7-Be) as soil redistribution tracer will be compared to other conventional water erosion methods. Keywords: Water erosion, conventional erosion assessment and measurement, nuclear techniques.

Mabit, Lionel

2010-05-01

209

Guidance and Control Software Project Data - Volume 1: Planning Documents  

NASA Technical Reports Server (NTRS)

The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the planning documents from the GCS project. Volume 1 contains five appendices: A. Plan for Software Aspects of Certification for the Guidance and Control Software Project; B. Software Development Standards for the Guidance and Control Software Project; C. Software Verification Plan for the Guidance and Control Software Project; D. Software Configuration Management Plan for the Guidance and Control Software Project; and E. Software Quality Assurance Activities.

Hayhurst, Kelly J. (Editor)

2008-01-01

210

Design of decentralized multivariable excitation controllers in multimachine power systems by projective controls  

SciTech Connect

A methodology for the design of decentralized multivariable excitation and controllers in multimachine power systems is developed using projective controls. The existing methodology, is extended to permit the coordinated design of AVR and PSS controllers in power systems.

Arnautovic, D.; Medanic, J.

1987-12-01

211

Project W-049H instrument and control Acceptance Test Procedure  

SciTech Connect

The purpose of this Acceptance Test Procedure (ATP) for the Project W-049H, Treated Effluent Disposal Facility, is to verify that the instrument and control systems have been installed in accordance with the design documents and function as required by the project criteria. The instrument and control system includes three operator control stations, modems, and general purpose LAN interface cabinets in the Effluent Treatment Facility control room; two pump stations; disposal station pumping building; and all local control units installed in the fold. Testing will be performed using actual signals when available and simulated signals when actual signals are unavailable.

Carrigan, M.C.

1994-11-16

212

Radiological evaluation of erosions  

PubMed Central

1 The most reliable method for evaluating possible remission-inducing properties in a drug is to measure how well it prevents the appearance of new erosions in serial X-rays of the hands. 2 I have reviewed the literature on the development, over the last 25 years, of a standard method for quantitatively assessing the progress of erosions radiologically. 3 The only drugs thus far shown to be genuinely remission-inducing are cyclophosphamide, high-dose penicillamine, and (most consistently over several decades) gold-thiols, all drugs with life-threatening toxicity. 4 The search for a non-steroidal drug with remission-inducing properties is crucial in our efforts to find a safe drug to control the progression of rheumatoid arthritis. PMID:3620278

O'Brien, W. M.

1986-01-01

213

Project Control for Healthcare Information Systems Initiatives  

Microsoft Academic Search

If left unchecked, trends in healthcare will overwhelm our tax base. Information and communication technologies (ICTs) have the potential to improve quality of care and lower costs. They also have the potential to deliver new forms of care that will save money in the long term. The problem is that information technology projects are difficult to implement. This paper uses

Lorne D. Booker; H. Trabulsi

2009-01-01

214

A comparative study of toluidine blue-mediated photodynamic therapy versus topical corticosteroids in the treatment of erosive-atrophic oral lichen planus: a randomized clinical controlled trial.  

PubMed

Recently, photodynamic therapy (PDT) has been suggested as a new treatment option that is free from side effects for erosive-atrophic oral lichen planus (OLP). The purpose of this study was to compare the effect of toluidine blue-mediated photodynamic therapy (TB-PDT) with local corticosteroids on treatment of erosive-atrophic OLP. In this randomized clinical trial, 25 patients with keratotic-atrophic-erosive oral lichen planus were allocated randomly into two groups. Group 1 (experimental): topical application of toluidine blue with micropipette was applied, and after 10 min, the patients were treated with a 630-nm GaAlAs laser (power density: 10 mW/cm(2)) during two visits. Group 2 (control) used mouthwash diluted with dexamethasone (tab 0/5 in 5 ml water) for 5 min, and then, it was spat out, and after 30 min, the mouth was rinsed with 30 drops of nystatin 100,000 units for 5 min and again spat out. Demographic data, type, and severity of the lesions and pain were recorded before and after treatment and then at the 1-month follow-up visit. Response rate was defined based on changes in intensity of the lesions and pain. In the experimental and control groups, sign scores of changes significantly reduced after treatment respectively (p?=?0.021) and (p?=?0.002), but between the two groups, no significant difference was observed (p?=?0.72). In the experimental (p?=?0.005) and control groups (p?=?0.001), the intensity of lesions significantly reduced after treatment and there was a significant difference between the two groups (p?=?0.001). The mean amount of improvement in pain was significantly greater in the control group compared with the experimental group (p?

Jajarm, Hasan Hoseinpour; Falaki, Farnaz; Sanatkhani, Majid; Ahmadzadeh, Meysam; Ahrari, Farzaneh; Shafaee, Hooman

2014-12-01

215

Guidance and Control Software Project Data - Volume 2: Development Documents  

NASA Technical Reports Server (NTRS)

The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the development documents from the GCS project. Volume 2 contains three appendices: A. Guidance and Control Software Development Specification; B. Design Description for the Pluto Implementation of the Guidance and Control Software; and C. Source Code for the Pluto Implementation of the Guidance and Control Software

Hayhurst, Kelly J. (Editor)

2008-01-01

216

Feedback Control Theory and Processing System Log Streams Research Project  

E-print Network

Feedback Control Theory and Processing System Log Streams by Wei Xu Research Project Submitted, and on exploring general techniques of applying feedback control theory to distributed computer systems. We have. All problems addressed are solved systematically with feedback-control-theory. We discuss three uses

Xu, Wei

217

An Open Specification for Space Project Mission Operations Control Architectures  

NASA Technical Reports Server (NTRS)

An 'open specification' for Space Project Mission Operations Control Architectures is under development in the Spacecraft Control Working Group of the American Institute for Aeronautics and Astro- nautics. This architecture identifies 5 basic elements incorporated in the design of similar operations systems: Data, System Management, Control Interface, Decision Support Engine, & Space Messaging Service.

Hooke, A.; Heuser, W. R.

1995-01-01

218

Projection Operator: A Step Towards Certification of Adaptive Controllers  

NASA Technical Reports Server (NTRS)

One of the major barriers to wider use of adaptive controllers in commercial aviation is the lack of appropriate certification procedures. In order to be certified by the Federal Aviation Administration (FAA), an aircraft controller is expected to meet a set of guidelines on functionality and reliability while not negatively impacting other systems or safety of aircraft operations. Due to their inherent time-variant and non-linear behavior, adaptive controllers cannot be certified via the metrics used for linear conventional controllers, such as gain and phase margin. Projection Operator is a robustness augmentation technique that bounds the output of a non-linear adaptive controller while conforming to the Lyapunov stability rules. It can also be used to limit the control authority of the adaptive component so that the said control authority can be arbitrarily close to that of a linear controller. In this paper we will present the results of applying the Projection Operator to a Model-Reference Adaptive Controller (MRAC), varying the amount of control authority, and comparing controller s performance and stability characteristics with those of a linear controller. We will also show how adjusting Projection Operator parameters can make it easier for the controller to satisfy the certification guidelines by enabling a tradeoff between controller s performance and robustness.

Larchev, Gregory V.; Campbell, Stefan F.; Kaneshige, John T.

2010-01-01

219

Controls and Electronics in the LEBIT Project  

Microsoft Academic Search

The LEBIT project at the NSCL is an experiment under construction that will accept a high-energy beam from the coupled cyclotron and convert it to a low-energy, low-emittance beam. This low-energy beam will be used in a variety of experiments, including precision mass measurements of exotic nuclei. The experiment contains a gas-stopping cell followed by an ion transport and trapping

Elizabeth Janus

2002-01-01

220

Analysing, quantifying and modelling soil erosion on steep hillslopes in different climatic areas using LiDAR and SFM DEMs  

NASA Astrophysics Data System (ADS)

Soil erosion is a worldwide well known problem and has therefore been subject to various scientific studies, especially on agricultural areas. However soil erosion on steep hillslopes in mountainous drainage basins can be a threat to human infrastructure as it supplies material, e.g. for debris flows to torrents. The study presented here aims to analyse, quantify and model soil erosion on (very) steep hillslopes free of vegetation in different climatic areas ranging from South Germany to Central Italy. Multitemporal digital elevation models were acquired with terrestrial laserscanning and from terrestrial and aerial structure from motion-based imagery. Analysis of erosion is mainly based on slope wash and rill erosion during summer months as well as erosion through freezing and melting processes during winter months in catchments of the Bavarian Alps. Erosional processes in the Mediterranean are mainly controlled by different precipitation regimes throughout the year. Annual erosion and accumulation rates are quantified and used for modelling purposes. First results of the presented project show, that the amount of material eroded is mainly controlled by the size of the sediment contributing area. However there are also other controlling factors, such as slope angle, slope length and vegetation cover which are investigated within this project.

Neugirg, Fabian; Haas, Florian; Kaiser, Andreas; Schmidt, Jürgen; Becht, Michael

2014-05-01

221

MILA Antenna Control Unit Replacement Project  

NASA Technical Reports Server (NTRS)

The Air to Ground Subsystem (AGS) Antenna Control Units at the MILA Ground Network Tracking Station are at end-of-life and are being replaced. AGS consists of two antennas at MILA (Quad-Helix and Teltrac). Software was taken from the existing Subsystem Controller and modified for the Antenna Control Unit (ACU). The software is capable of receiving and sending commands to and from the ACU. Moving the azimuth clockwise, counterclockwise, moving the elevation up or down, turning servo power on and off, and inputting azimuth and elevation angles are commands that the antenna can receive.

Bresette, Jeremy

2007-01-01

222

Origin of Valles Marineris and Noctis Labyrinthus, Mars, by structurally controlled collapse and erosion of crustal materials  

NASA Astrophysics Data System (ADS)

Stratigraphic, structural, and geomorphologic relations indicate that the Valles Marineris (VM) and Noctis Labyrinthus troughs on Mars began their development in the Noachian as narrow grabens in response to Tharsis-centered stress and local magmatism. Following an apparent waning of VM tectonism during the Early Hesperian, the major trough-forming episode ensued during the Late Hesperian and Early Amazonian due to fluidization, collapse, and erosion of water-saturated, poorly consolidated crustal rocks through channels and subsurface conduits.

Tanaka, Kenneth L.

1997-03-01

223

Supporting the Future Air Traffic Control Projection Process  

E-print Network

In air traffic control, projecting what the air traffic situation will be over the next 30 seconds to 30 minutes is a key process in identifying conflicts that may arise so that evasive action can be taken upon discovery ...

Davison, H. J.

2003-01-01

224

MINE WASTE TECHNOLOGY PROGRAM - UNDERGROUND MINE SOURCE CONTROL DEMONSTRATION PROJECT  

EPA Science Inventory

This report presents results of the Mine Waste Technology Program Activity III, Project 8, Underground Mine Source Control Demonstration Project implemented and funded by the U. S. Environmental Protection Agency (EPA) and jointly administered by EPA and the U. S. Department of E...

225

Establishment of control site baseline data for erosion studies using radionuclides: a case study in East Slovenia.  

PubMed

The aim of the present study was to establish a reference site and its soil characteristics for use of fallout radionuclides in erosion studies in Slovenia. Prior to this study, no reference site and baseline data existed for Slovenia for this purpose. In the agricultural area of Goricko in East Slovenia, an undisturbed forest situated in Salamenci (46 degrees 44'N, 16 degrees 7'E), was selected to establish the inventory value of fallout 137Cs and to establish a baseline level of multi-elemental fingerprint (major, minor, trace elements including heavy metals) and naturally occurring radionuclides in soils. A total of 20 soil profiles were collected at four 10 cm depth increments for evaluation of baseline level of 137Cs inventory. An exponential distribution for 137Cs was found and the baseline level inventory was established at 7300 +/- 2500 Bq m-2 with a coefficient of variation of 34%. Of this mean present-day inventory, approximately 45% is due to the Chernobyl contribution. The physical degradation of soils through erosion is linked with biochemical degradation. This study introduces an approach to establishment of the naturally occurring radionuclide and elemental fingerprints baseline levels at a reference site which can provide comparative data to those from neighbouring agricultural fields for assessment of soil redistribution magnitude using fallout radionuclides. In addition, this information will be used to determine the impact of soil erosion processes and agricultural practices on soil quality and redistribution within agricultural landscapes in Slovenia. PMID:20687248

Mabit, Lionel; Martin, Paul; Jankong, Patcharin; Toloza, Arsenio; Padilla-Alvarez, Roman; Zupanc, Vesna

2010-10-01

226

Establishment of control site baseline data for erosion studies using radionuclides: a case study in East Slovenia.  

PubMed

The aim of the present study was to establish a reference site and its soil characteristics for use of fallout radionuclides in erosion studies in Slovenia. Prior to this study, no reference site and baseline data existed for Slovenia for this purpose. In the agricultural area of Gori?ko in East Slovenia, an undisturbed forest situated in Šalamenci (46°44'N, 16°7'E), was selected to establish the inventory value of fallout (137)Cs and to establish a baseline level of multi-elemental fingerprint (major, minor, trace elements including heavy metals) and naturally occurring radionuclides in soils. A total of 20 soil profiles were collected at four 10 cm depth increments for evaluation of baseline level of (137)Cs inventory. An exponential distribution for (137)Cs was found and the baseline level inventory was established at 7300 ± 2500 Bq m(-2) with a coefficient of variation of 34%. Of this mean present-day inventory, approximately 45% is due to the Chernobyl contribution. The physical degradation of soils through erosion is linked with biochemical degradation. This study introduces an approach to establishment of the naturally occurring radionuclide and elemental fingerprints baseline levels at a reference site which can provide comparative data to those from neighbouring agricultural fields for assessment of soil redistribution magnitude using fallout radionuclides. In addition, this information will be used to determine the impact of soil erosion processes and agricultural practices on soil quality and redistribution within agricultural landscapes in Slovenia. PMID:20965104

Mabit, Lionel; Martin, Paul; Jankong, Patcharin; Toloza, Arsenio; Padilla-Alvarez, Roman; Zupanc, Vesna

2010-06-01

227

Projective synchronization in fractional order chaotic systems and its control  

E-print Network

The chaotic dynamics of fractional (non-integer) order systems have begun to attract much attention in recent years. In this paper, we study the projective synchronization in two coupled fractional order chaotic oscillators. It is shown that projective synchronization can also exist in coupled fractional order chaotic systems. A simple feedback control method for controlling the scaling factor onto a desired value is also presented.

Chunguang Li

2006-04-24

228

Soil and Sediment Erosion  

NSDL National Science Digital Library

This brief article discusses the effect of soil and sediment erosion and its significance in social and economic aspects. The methods of measuring erosion and knowledge of past erosion rates are also briefly discussed to use as a predictor of future erosion rates.

2008-09-22

229

SOIL EROSION AND PRODUCTIVITY  

E-print Network

SOIL EROSION AND PRODUCTIVITY DICK WOLKOWSKI DEPARTMENT OF SOIL SCIENCE UW-MADISON #12;SOIL EROSION/a/yr 30% OF US FARMLAND ABANDONED EROSION SALINIZATION WATER-LOGGING 90% OF US CROPLAND LOSING SOIL FASTER THAN IT IS REPLACED >1 t/a/yr PIMENTEL ET AL., 1995 #12;SOIL EROSION WATER AND WIND LOSSES CAN

Balser, Teri C.

230

Cause of Erosion Mitigation  

E-print Network

and watershed restoration. 354p. 2005, Morgan, Soil Erosion and Conservation Johnson, 2003 Design of Erosion of Erosion "Dislodgement and transportation of soil materials through the action of water and wind" Spitz erosion (~6m/s, 0.6m movement vertically of soil particles) 2.Movement of water over surface dislodges

Boisvert, Jeff

231

Supporting the Future Air Traffic Control Projection Process  

NASA Technical Reports Server (NTRS)

In air traffic control, projecting what the air traffic situation will be over the next 30 seconds to 30 minutes is a key process in identifying conflicts that may arise so that evasive action can be taken upon discovery of these conflicts. A series of field visits in the Boston and New York terminal radar approach control (TRACON) facilities and in the oceanic air traffic control facilities in New York and Reykjavik, Iceland were conducted to investigate the projection process in two different ATC domains. The results from the site visits suggest that two types of projection are currently used in ATC tasks, depending on the type of separation minima and/or traffic restriction and information display used by the controller. As technologies improve and procedures change, care should be taken by designers to support projection through displays, automation, and procedures. It is critical to prevent time/space mismatches between interfaces and restrictions. Existing structure in traffic dynamics could be utilized to provide controllers with useful behavioral models on which to build projections. Subtle structure that the controllers are unable to internalize could be incorporated into an ATC projection aid.

Davison, Hayley J.; Hansman, R. John, Jr.

2002-01-01

232

Guidance and Control Software Project Data - Volume 3: Verification Documents  

NASA Technical Reports Server (NTRS)

The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the verification documents from the GCS project. Volume 3 contains four appendices: A. Software Verification Cases and Procedures for the Guidance and Control Software Project; B. Software Verification Results for the Pluto Implementation of the Guidance and Control Software; C. Review Records for the Pluto Implementation of the Guidance and Control Software; and D. Test Results Logs for the Pluto Implementation of the Guidance and Control Software.

Hayhurst, Kelly J. (Editor)

2008-01-01

233

Erosion control blankets, organic amendments and site variability influenced the initial plant community at a limestone quarry in the Canadian Rocky Mountains  

NASA Astrophysics Data System (ADS)

Season of seeding and soil amendment with manure mix, wood shavings and erosion control blankets were evaluated over two growing seasons to determine their effect on soil properties and native grass establishment at a Canadian limestone quarry and lime processing plant. Season (fall, spring) of soil amending and seeding did not significantly affect revegetation or soil properties. Site characteristics such as slope, aspect, initial soil nutrients and surrounding plant communities influenced early plant community development and overall effects of soil treatments. Erosion control blankets resulted in the highest seeded plant cover and the lowest non seeded plant cover despite not significantly changing soil chemical properties. Total nitrogen and carbon significantly increased establishment of seeded grasses and non seeded species. Increased nitrogen and carbon in the constructed soils were best achieved through addition of manure. Wood shavings did not favour establishment of vegetation and resulted in similar, and in some cases less, vegetation than controls. Assisted revegetation increased plant cover from < 6 to 50% and reduced cover of non seeded species. Amendments that modified both chemical and physical soil conditions were best to increase vegetation establishment in the harsh conditions of the quarry.

Cohen-Fernández, A. C.; Naeth, M. A.

2013-02-01

234

Erosion control blankets, organic amendments and site variability influenced the initial plant community at a limestone quarry in the Canadian Rocky Mountains  

NASA Astrophysics Data System (ADS)

Season of seeding and soil amendment with manure mix, wood shavings and erosion control blankets were evaluated over two growing seasons to determine their effect on soil properties and native grass establishment at a Canadian limestone quarry and lime processing plant. A season (fall, spring) of soil amending and seeding did not significantly affect revegetation or soil properties. Site characteristics such as slope, aspect, initial soil nutrients and surrounding plant communities influenced early plant community development and overall effects of soil treatments. Erosion control blankets resulted in the highest seeded plant cover and the lowest non-seeded plant cover despite not significantly changing soil chemical properties. Total nitrogen and carbon significantly increased establishment of seeded grasses and non-seeded species. Increased nitrogen and carbon in the constructed soils were best achieved through addition of manure. Wood shavings did not favour establishment of vegetation and resulted in similar, and in some cases less, vegetation than the controls. Assisted revegetation increased plant cover from < 6 to 50% and reduced cover of non-seeded species. Amendments that modified both chemical and physical soil conditions were best to increase vegetation establishment in the harsh conditions of the quarry.

Cohen-Fernández, A. C.; Naeth, M. A.

2013-07-01

235

Micro-Management of Lighting Controls Projects  

E-print Network

the reduction of electricity spent on lighting. These controls turn off the llghtlng in a mom or area when it is not occupied. The sensors can operate on the basis of sound. heat or light detection or a combtnatton thereot. The sensitivity can be varied... also reduce the cooling load of a building. Thle translates into additional savings Each sensor type has an ideal application. The selection is prtmarUy governed by the function of the area. The choice of moms to be considered for controls...

Clark, W. H.

1994-01-01

236

18 CFR 380.4 - Projects or actions categorically excluded.  

Code of Federal Regulations, 2010 CFR

...into project waters, water mains, piers, landings, boat docks, or similar structures and facilities, landscaping or embankments, bulkheads, retaining walls, or similar shoreline erosion control structures; (20) Action on applications for...

2010-04-01

237

Wind Erosion Research  

NSDL National Science Digital Library

Wind Erosion Research (WER) provides science-based wind erosion technology for environmentally, economically, and socially sustainable agriculture in the United States. This website introduces the Wind Erosion Equation (WEQ), the first model for estimating soil loss by wind from agricultural fields and the newly developed Wind Erosion Prediction System (WEPS) which provides new capabilities assessing plant damage and calculating suspension loss. Simulation models, multimedia archive and history of wind erosion research are available for educators and students.

2006-02-27

238

Gully erosion and environmental change: importance and research needs  

Microsoft Academic Search

Assessing the impacts of climatic and, in particular, land use changes on rates of soil erosion by water is the objective of many national and international research projects. However, over the last decades, most research dealing with soil erosion by water has concentrated on sheet (interrill) and rill erosion processes operating at the (runoff) plot scale. Relatively few studies have

J Poesen; J Nachtergaele; G Verstraeten; C Valentin

2003-01-01

239

Dust control at Yucca Mountain project  

SciTech Connect

This report describes actions taken to control silica dust at the Yucca Mountain Exploratory Studies Facility, a tunnel located in Southern Nevada that is part of a scientific program to determine site suitability for a potential nuclear waste repository. The rock is a volcanic tuff containing significant percentages of both quartz and cristobalite. Water use for dust control was limited because of scientific test requirements, and this limitation made dust control a difficult task. Results are reported for two drifts, called the Main Loop Drift and the Cross Drift. In the Main Loop Drift, dust surveys and tracer gas tests indicated that air leakage from the TBM head, the primary ventilation duct, and movement of the conveyor belt were all significant sources of dust. Conventional dust control approaches yielded no significant reductions in dust levels. A novel alternative was to install an air cleaning station on a rear deck of the TBM trailing gear. It filtered dust from the contaminated intake air and discharged clean air towards the front of the TBM. The practical effect was to produce dust levels below the exposure limit for all TBM locations except close to the head. In the Cross Drift, better ventilation and an extra set of dust seals on the TBM served to cut down the leakage of dust from the TBM cutter head. However, the conveyor belt was much dustier than the belt in the main loop drift. The problem originated with dirt on the bottom of the belt return side and much spillage from the belt top side. Achieving lower dust levels in hard rock tunneling operations will require new approaches as well as a more meticulous application of existing technology. Planning for dust control will require specific means to deal with dust that leaks from the TBM head, dust that originates with leaky ventilation systems, and dust that comes from conveyor belts. Also, the application of water could be more efficient if automatic controls were used to adjust the water flow rate to the mining rate.

Kissell, F.; Jurani, R.; Dresel, R.; Reaux, C.

1999-07-01

240

Field studies of beach cones as coastal erosion control/reversal devices for areas with significant oil and gas activities. [Annual report], February 24, 1992--February 23, 1993  

SciTech Connect

The primary objective of this project is to evaluate the utility of a device called the ``beach cone`` in combating coastal erosion. Seven initial sites were selected for testing beach cones in a variety of geometric configurations. Permits were obtained from the State of Louisiana and the US Army Corps of Engineers to perform the work associated with this study. Six hundred beach cones were actually installed at six of the sites in late July and early August, 1992. One of the initial sites was abandoned because it was found to be unsuitable for beach cone placement. The test sites have been observed for six months and preliminary findings indicate that beach cones accreted significant amounts of materials along the beach of a barrier island. At other test sites, accretion rates have been less dramatic but importantly, no significant additional erosion has occurred, which is a positive result. It is too soon to state the categorical success of the beach cones, but results to date are encouraging.

Law, V.J.

1993-03-15

241

Project: Driver and controller for a thermoelectric cooler  

E-print Network

Project: Driver and controller for a thermoelectric cooler Supervisor: Prof. Sam Ben-Yaakov Year solutions. Based on one of the three thermoelectric phenomena ­ the Peltier effect ­ bi-directional control is achieved. The TEC (which is a Thermoelectric Cooler) uses this effect. The direction of the current through

242

Microprocessor-based monitoring and control project: Phase 2 report  

SciTech Connect

This report summarizes the activities of Phase II of the microprocessor-based monitoring and control project. The object of this multiphase project in the Electrical Systems Group of TVA's Division of Energy Demonstration and Technology (ED and T) is the development of microprocessor-based systems for special-purpose applications in monitoring, control, and protection of the power system. Phase II dealt with the hardware enhancements and software development to simulate the switching of the 46-kV capacitor banks at the Concord substation for voltage and VAR control.

Not Available

1986-09-01

243

CLEAR LAKE BASIN 2000 PROJECT  

SciTech Connect

The following is a final report for the Clear Lake Basin 2000 project. All of the major project construction work was complete and this phase generally included final details and testing. Most of the work was electrical. Erosion control activities were underway to prepare for the rainy season. System testing including pump stations, electrical and computer control systems was conducted. Most of the project focus from November onward was completing punch list items.

LAKE COUNTY SANITATION DISTRICT

2003-03-31

244

Overview of NASA's Thermal Control System Development for Exploration Project  

NASA Technical Reports Server (NTRS)

NASA's Constellation Program includes the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, are manned space vehicles while the third element is broader and includes several sub-elements including Rovers and a Lunar Habitat. The upcoming planned missions involving these systems and vehicles include several risks and design challenges. Due to the unique thermal environment, many of these risks and challenges are associated with the vehicles' thermal control system. NASA's Exploration Systems Mission Directorate (ESMD) includes the Exploration Technology Development Program (ETDP). ETDP consists of several technology development projects. The project chartered with mitigating the aforementioned risks and design challenges is the Thermal Control System Development for Exploration Project. The risks and design challenges are addressed through a rigorous technology development process that culminates with an integrated thermal control system test. The resulting hardware typically has a Technology Readiness Level (TRL) of six. This paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing assessments for thermal control system fluids.

Stephan, Ryan A.

2010-01-01

245

F-15 837 IFCS Intelligent Flight Control System Project  

NASA Technical Reports Server (NTRS)

This viewgraph presentation reviews the use of Intelligent Flight Control System (IFCS) for the F-15. The goals of the project are: (1) Demonstrate Revolutionary Control Approaches that can Efficiently Optimize Aircraft Performance in both Normal and Failure Conditions (2) Advance Neural Network-Based Flight Control Technology for New Aerospace Systems Designs. The motivation for the development are to reduce the chance and skill required for survival.

Bosworth, John T.

2007-01-01

246

Building the evidence base for effective tobacco control policies: the International Tobacco Control Policy Evaluation Project (the ITC Project)  

PubMed Central

The Framework Convention on Tobacco Control (FCTC) is a seminal event in tobacco control and in global health. Scientific evidence guided the creation of the FCTC, and as the treaty moves into its implementation phase, scientific evidence can be used to guide the formulation of evidence?based tobacco control policies. The International Tobacco Control Policy Evaluation Project (ITC Project) is a transdisciplinary international collaboration of tobacco control researchers who have created research studies to evaluate and understand the psychosocial and behavioural impact of FCTC policies as they are implemented in participating ITC countries, which together are inhabited by over 45% of the world's smokers. This introduction to the ITC Project supplement of Tobacco Control presents a brief outline of the ITC Project, including a summary of key findings to date. The overall conceptual model and methodology of the ITC Project—involving representative national cohort surveys created from a common conceptual model, with common methods and measures across countries—may hold promise as a useful paradigm in efforts to evaluate and understand the impact of population?based interventions in other important domains of health, such as obesity. PMID:16754940

Fong, G T; Cummings, K M

2006-01-01

247

Mechanisms of polymer degradation and erosion  

Microsoft Academic Search

The most important features of the degradation and erosion of degradable polymers in vitro are discussed. Parameters of chemical degradation, which is the scission of the polymer backbone, are described such as the type of polymer bond, pH and copolymer composition. Examples are given how these parameters can be used to control degradation rates. Degradation leads finally to polymer erosion,

Achim Göpferich

1996-01-01

248

Erosion in Our World  

NSDL National Science Digital Library

This activity is a field investigation where students find real-life examples of erosion in their school surroundings. Students will extend what they learned during stream table lessons about erosion, deposition, deltas, meandering streams, and dams.

Payeur, Abbey

249

Improving soil bioengineering techniques to control erosion and sedimentation within the context of torrential Mediterranean climate: a French-Canadian experience  

NASA Astrophysics Data System (ADS)

On marly eroded terrains of the French Southern Alps, many researches are undertaken in order to better understand the role of vegetation and bioengineering works on erosion and sedimentation control. To this view, the eroded marly gullies of the French Southern Alps are an experimental design where an original French strategy of rehabilitation, developed by scientists from Irstea (ex-Cemagref), has been tested since 2002. It is comprised of the construction of bioengineering works, namely of "brush layers and brush mats of cuttings on deadwood microdams", and implements the use of willow cuttings (Salix purpurea and S. incana). The main objective of these works is to sustainably trap and retain marly sediment, by checking their performance (growth and survival of the cuttings, sediment trapping) in a mountainous and Mediterranean climate. In Canada, several private companies have developed their own knowledge and expertise in the conception and building of bioengineering works for erosion control, especially in the context of hilly and mountainous landscapes and climates. Therefore, it was decided to use the competence and expertise of Terra Erosion Control Ltd., a Canadian company, in the French torrential Mediterranean climate. Ten modalities were tested, the aims being to develop and/or to modify existing designs of current techniques, to experiment with other live cuttings (Populus nigra) and rooted species (Alnus spp. and Hippophae spp.), to evaluate and compare the potential use of different organic soil amendments in order to increase beneficial soil microorganisms and finally, to evaluate the potential use of specialized tools and equipment in order to increase the efficiency of the installation for vegetation establishment and sediment trapping, while decreasing the implementation costs. The experimental design was installed in March 2011 and the early observations in Spring 2012 showed that: 1/ most of the cuttings and the plants resisted to burial and to drought conditions; in particular, the structures using wooden boards instead of locally harvested logs appeared to be holding up well; 2/ designs of current techniques with vertical cuttings were better for resprouting and sediment trapping; 3/ 0.8m live cuttings of Populus nigra may represent an alternative to Salix spp., but resprout appeared lower; 4/ it was not possible to evaluate the performance of rooted species (Alnus spp. and Hippophae spp.); therefore more experiment is needed, especially with longer plants; 5/ organic soil amendments may increase vegetation development (BRF > fertilizer > compost > mixes). By comparing the results with similar sites used as benchmarks, installed since 2002, further observations in the spring of 2013 will allow us to evaluate the efficiency of the different modalities to improve vegetation establishment and sediment trapping.

Rey, Freddy; Louis, Séverine; Burylo, Mélanie; Raymond, Pierre

2013-04-01

250

Anthropogenic Effects on Erosion  

NSDL National Science Digital Library

This exercise focuses on anthropogenic effects on erosion. It could be run as a single lab or as a series of in-class exercises or problem sets. We discussed an article by Hooke and used it as a launching pad for a discussion of back of the envelope calculations. Students then estimate the volume moved by mountain-top removal and how long it might take a river to mobilize that sediment. They estimate the cost for beach nourishment along Florida beaches. They estimate the contribution of local construction projects and road gravel to stream sediment loads. This activity gives students a chance to formulate a problem, make simple measurements, estimate unknowns, and calculate volumes, rates, and costs of various human earth-moving activities. Designed for a geomorphology course Addresses student fear of quantitative aspect and/or inadequate quantitative skills Uses geomorphology to solve problems in other fields

Karen Gran

251

Overview of NASA's Thermal Control System Development for Exploration Project  

NASA Technical Reports Server (NTRS)

The now-cancelled Constellation Program included the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, were planned to be manned space vehicles while the third element was much more diverse and included several sub-elements. Among other things, these sub-elements were Rovers and a Lunar Habitat. The planned missions involving these systems and vehicles included several risks and design challenges. Due to the unique thermal operating environment, many of these risks and challenges were associated with the vehicles thermal control system. NASA s Exploration Technology Development Program (ETDP) consisted of various technology development projects. The project chartered with mitigating the aforementioned thermal risks and design challenges was the Thermal Control System Development for Exploration Project. These risks and design challenges were being addressed through a rigorous technology development process that was planned to culminate with an integrated thermal control system test. Although the technologies being developed were originally aimed towards mitigating specific Constellation risks, the technology development process is being continued within a new program. This continued effort is justified by the fact that many of the technologies are generically applicable to future spacecraft thermal control systems. The current paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing a material compatibility assessment for a promising thermal control system working fluid. The to-date progress and lessons-learned from these development efforts will be discussed throughout the paper.

Stephan, Ryan A.

2011-01-01

252

PREDICTING MINESOIL EROSION POTENTIAL  

EPA Science Inventory

Two experimental plots were instrumented with erosion pins to study the correspondence between point erosion and erosion over an area on strip mine soil. Using a rotating boom rainfall simulator, data were collected by sampling the runoff every five minutes for the duration of th...

253

Cause of Erosion Mitigation  

E-print Network

and watershed restoration. 354p. Definition of Erosion "Dislodgement and transportation of soil materials of raindrop dislodges soil particles, splash erosion (~6m/s, 0.6m movement vertically of soil particles) 2.Movement of water over surface dislodges and transports soil, Sheet, Rill, Gully, channel #12;01-2 Erosion

Boisvert, Jeff

254

Modeling soil erosion on steep sagebrush rangeland before and after prescribed fire  

Microsoft Academic Search

Fire in sagebrush rangelands significantly alters canopy cover, ground cover, and soil properties which influence runoff and erosion processes. Runoff can be generated more quickly and in larger volume following fire resulting in increased risk of severe erosion and downstream flooding. The Water Erosion Prediction Project (WEPP) model was developed to predict erosion on cropland, forest, and rangeland. WEPP is

Corey A. Moffet; Frederick B. Pierson; Peter R. Robichaud; Kenneth E. Spaeth; Stuart P. Hardegree

2007-01-01

255

Proceedings, 2001National Conference on Beach Preservation Technology, pp. 274-283 COASTAL INLET BANK EROSION  

E-print Network

BANK EROSION William C. Seabergh 1 Abstract: Much focus is placed on beach erosion on the open coast erosion. These shorelines lie adjacent to coastal inlets and extend around the inlet from the ocean to bay shoreline develop inner-bank erosion in the absence of preventive measures. Many mature projects show eroded

US Army Corps of Engineers

256

Simulation of Surface Erosion on a Logging Road in the Jackson Demonstration State  

E-print Network

Simulation of Surface Erosion on a Logging Road in the Jackson Demonstration State Forest1 Teresa delivery to streams, we have used a simulation model of road surface erosion known as the Watershed Erosion Prediction Project (WEPP) model, developed by the USDA Forest Service. This model predicts discharge, erosion

Standiford, Richard B.

257

SOLERAS - Solar Controlled Environment Agriculture Project. Final report, Volume 1. Project summary  

SciTech Connect

A summary of the Solar Controlled Environment Agriculture Project is presented. The design of the greenhouses include transparent double pane glass roof with channels for fluid between the panes, inner pane tinted and double pane extruded acrylic aluminized mylar shade and diffuser. Solar energy technologies provide power for water desalination, for pumping irrigation water, and for cooling and heating the controlled environment space so that crops can grow in arid lands. The project is a joint effort between the United States and Saudi Arabia. (BCS)

Not Available

1985-12-30

258

Relationship of runoff, erosion and sediment yield to weather types in the Iberian Peninsula  

NASA Astrophysics Data System (ADS)

Precipitation has been recognized as one of the main factors driving soil erosion and sediment yield (SY), and its spatial and temporal variability is recognized as one of the main reasons for spatial and temporal analyses of soil erosion variability. The weather types (WTs) approach classifies the continuum of atmospheric circulation into a small number of categories or types and has been proven a good indicator of the spatial and temporal variability of precipitation. Thus, the main objective of this study is to analyze the relationship between WTs, runoff, soil erosion (measured in plots), and sediment yield (measured in catchments) in different areas of the Iberian Peninsula (IP) with the aim of detecting spatial variations in these relationships. To this end, hydrological and sediment information covering the IP from several Spanish research teams has been combined, and related with daily WTs estimated by using the NMC/NCAR 40-Year Reanalysis Project. The results show that, in general, a few WTs (particularly westerly, southwesterly and cyclonic) provide the largest amounts of precipitation; and southwesterly, northwesterly and westerly WTs play an important role in runoff generation, erosion and sediment yield as they coincide with the wettest WTs. However, this study highlights the spatial variability of erosion and sediment yield in the IP according to WT, differentiating (1) areas under the influence of north and/or north-westerly flows (the north coast of Cantabria and inland central areas), (2) areas under the influence of westerly, southwesterly and cyclonic WTs (western and southwestern IP), (3) areas in which erosion and sediment yield are controlled by easterly flows (Mediterranean coastland), and (4) lastly, a transitional zone in the inland northeast Ebro catchment, where we detected a high variability in the effects of WTs on erosion. Overall results suggest that the use of WTs derived from observed atmospheric pressure patterns could be a useful tool for inclusion in future projections of the spatial variability of erosion and sediment yield, as models capture pressure fields reliably.

Nadal-Romero, E.; González-Hidalgo, J. C.; Cortesi, N.; Desir, G.; Gómez, J. A.; Lasanta, T.; Lucía, A.; Marín, C.; Martínez-Murillo, J. F.; Pacheco, E.; Rodríguez-Blanco, M. L.; Romero Díaz, A.; Ruiz-Sinoga, J. D.; Taguas, E. V.; Taboada-Castro, M. M.; Taboada-Castro, M. T.; Úbeda, X.; Zabaleta, A.

2015-01-01

259

Substation control and protection project: System requirements specifications  

SciTech Connect

This specification was developed during Phase I of EPRI Project RP1359-1 and was published as EL-1813 in April of 1983. This project involves the design and implementation of a microprocessor-based, integrated protection, and control system for transmission class substations. In order to define the scope of the system, a list of possible functions was generated and the requirements for each function were defined after extensive consultation with Host Utility personnel and with other Utility Advisors. A list of general system requirements and design criteria was also generated. This specification served as the starting point for the development of detailed functional specifications and subsequent implementation specifications. The requirements were the design goals whose feasibility and practicality were tested for those functions chosen during the design, implementation, and demonstration phases of the project. This report updates the earlier report through revisions and additions. The changes reflect added knowledge gained during the latter stages of the project.

Deliyannides, J.S. (Westinghouse Electric Corp., East Pittsburgh, PA (USA))

1989-11-01

260

Integrated Quality Control Measurement Project. Findings and Corrective Actions.  

ERIC Educational Resources Information Center

The Integrated Quality Control Measurement Project (IQCMP) of the U.S. Department of Education measured the quality of awards distributed during the 1988-89 award year under the three major Title IV programs: the Pell Grant program, the Campus-Based programs, and the Stafford Loan program, in order to evaluate and improve the quality of the…

Price Waterhouse and Co., New York, NY.

261

Adaptive aid for environmental control: the ASPICE project  

Microsoft Academic Search

The quality of life of people suffering from severe motor disabilities can benefit from the use of current assistive technology capable of ameliorating communication, house-environment management and mobility, according to the user's residual motor abilities. The ASPICE project aims to develop an Assistive System for Patient's Increase of Communication, ambient control and mobility in absence of muscular Effort. Different disability

Fabio Aloise; Donatella Mattia; Fabio Babiloni; Simona Bufalari; Serenella Salinari; Maria Grazia Marciani; Febo Cincotti

262

Field studies of beach cones as coastal erosion control/reversal devices for areas with significant oil and gas activities. Final report, February 24, 1992--September 18, 1995  

SciTech Connect

The primary objective of this project was to evaluate the utility of a device called the {open_quotes}beach cone{close_quotes} in combating coastal erosion. Seven initial sites were selected for testing beach cones in a variety of geometric configurations. Permits were obtained from the State of Louisiana and the U.S. Army Corps of Engineers to perform the work associated with this study. Six hundred beach cones were actually installed at six of the sites in late July and early August, 1992. Findings indicate that beach cones accreted significant amounts of materials along the beach of a barrier island, and they might have been instrumental in repairing an approximately 200 meter gap in the island. At the eighth installation the amount of accreted material was measured by surveys to be 2200 cubic meters (2900 cubic yards) in February of 1993, when the cones were found to have been completely covered by the material. At other test sites, accretion rates have been less dramatic but importantly, no significant additional erosion has occurred, which is a positive result. The cost of sediment accretion using beach cones was found to be about $13.72 per cubic yard, which would be much lower if the cones were mass produced (on the order of $3.00 per cubic yard). The survival of the cones through the fringes of Hurricane Andrew indicates that they can be anchored sufficiently to survive significant storms. The measurements of the cones settling rates indicate that this effect is not significant enough to hinder their effectiveness. A subcontract to Xavier University to assess the ecological quality of the experimental sites involved the study of the biogeochemical cycle of trace metals. The highest concentration of heavy metals were near a fishing camp while the lowest levels were in the beach sand of a barrier island. This suggests that the metals do not occur naturally in these areas, but have been placed in the sediments by man`s activities.

Law, V.J.

1995-09-18

263

15 CFR 923.25 - Shoreline erosion/mitigation planning.  

...2014-01-01 2014-01-01 false Shoreline erosion/mitigation planning. 923.25 Section...Management Areas § 923.25 Shoreline erosion/mitigation planning. (a) The...control, or lessen the impact of, shoreline erosion, including potential impacts of...

2014-01-01

264

15 CFR 923.25 - Shoreline erosion/mitigation planning.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Shoreline erosion/mitigation planning. 923.25 Section...Management Areas § 923.25 Shoreline erosion/mitigation planning. (a) The...control, or lessen the impact of, shoreline erosion, including potential impacts of...

2013-01-01

265

15 CFR 923.25 - Shoreline erosion/mitigation planning.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Shoreline erosion/mitigation planning. 923.25 Section...Management Areas § 923.25 Shoreline erosion/mitigation planning. (a) The...control, or lessen the impact of, shoreline erosion, including potential impacts of...

2010-01-01

266

15 CFR 923.25 - Shoreline erosion/mitigation planning.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Shoreline erosion/mitigation planning. 923.25 Section...Management Areas § 923.25 Shoreline erosion/mitigation planning. (a) The...control, or lessen the impact of, shoreline erosion, including potential impacts of...

2012-01-01

267

Erosion and Sedimentation as Part of the Natural System1  

E-print Network

Erosion and Sedimentation as Part of the Natural System1 Robert B. Howard2 1 Presented Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture; 1982. 403 Erosion of erosion or sedimentation however differs from one environment to another. Various factors control

Standiford, Richard B.

268

15 CFR 923.25 - Shoreline erosion/mitigation planning.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Shoreline erosion/mitigation planning. 923.25 Section...Management Areas § 923.25 Shoreline erosion/mitigation planning. (a) The...control, or lessen the impact of, shoreline erosion, including potential impacts of...

2011-01-01

269

Threshold phenomena in erosion driven by subsurface flow  

E-print Network

Threshold phenomena in erosion driven by subsurface flow Alexander E. Lobkovsky Department of Earth of the three modes of sediment mobilization in this experiment: surface erosion, fluidization, and slumping. The onset of erosion is controlled not only by shear stresses caused by surfical flows but also

Kudrolli, Arshad

270

Links between erosion, runoff variability, and seismicity in the Taiwan orogen  

Microsoft Academic Search

Erosion of mountain belts controls their topographic and structural evolution and is the main source of sediment delivered to the oceans. While mountain erosion rates have been estimated from relief and precipitation, full evaluation of controls on erosion rates and patterns is challenging and requires detailed measurements across multiple time-scales. We report erosion rates in the Taiwan mountains estimated from

Simon J. Dadson; Niels Hovius; Hongey Chen; W. Brian Dade; Meng-Long Hsieh; Sean D. Willett; Jyr-Ching Hu; Ming-Jame Horng; Meng-Chiang Chen; Colin P. Stark; Dimitri Lague; Jiun-Chuan Lin

2003-01-01

271

Predicting sheetwash and rill erosion over the Australian continent  

Microsoft Academic Search

Abstract Soil erosion is a major environmental,issue in Australia. It reduces land productivity and has off-site effects ofdecreased,water quality. Broad-scale spatially distributed soil erosion estimation ,is essential ,for prioritising erosion control programs ,and as a ,component ,of broader ,assessments ,of natural ,resource condition. This paper describes spatial modelling ,methods ,and results that predict sheetwash ,and rill erosion over the Australian

Hua Lu; Ian P. Prosser; Chris J. Moran; John C. Gallant; Graeme Priestley; Janelle G. Stevenson

2003-01-01

272

[Functions of different cultivation modes in oasis agriculture on soil wind erosion control and soil moisture conservation].  

PubMed

During 2001-2002, the effects of different cultivation modes including winter irrigation and zero tillage, crop-grass intercropping, and early spring film mulching on sand entrainment, wind velocity gradient and soil moisture conservation were studied in the middle reaches of the Heihe River in the Hexi Corridor region. The results showed that all these modes could reduce soil wind erosion and halt sand entrainment to different degrees. Compared with the bare fields exposed by spring plowing, early spring film mulching could increase soil moisture storage by 35.6%. At present, spring plowing and sowing was a main factor responsible to the occurrence of sand storms and the increase in suspended dust content. Farmlands in the upper and middle reaches of the Heihe River generally produced a dust transport up to 4.8-6.0 million tons per year, which was higher than that of sandy desert in the same region. In the Hexi Corridor region, the suspended dust amount produced from 1 hm2 farmland was equivalent to that of 1.5 hm2 desert. PMID:15669480

Su, Peixi; Zhao, Aifen; Du, Mingwu

2004-09-01

273

Sustation control and protection project: Communication interface specification  

SciTech Connect

This communication interface specification was developed during Phase I of EPRI Project RP 1359-1 and continued to evolve during Project RP 1359-7. The project concerns the design and implementation of a microprocessor-based, integrated protection and control system for transmission class substations. The various elements of the system are arranged in a hierarchy. This specifications defines the interfaces between the various levels of hierarchy. The need for a well-defined, standard interface specification becomes more apparent when considering the fact that different manufactures may be supplying equipment within the same substation. The specification considers each level of the hierarchy and defines the physical characteristics, the signal characteristics, the hardware and message protocol, the message framing and the user level data structures for each interface. 10 figs.

Not Available

1989-11-01

274

Soil Erosion Protection Potential of Young Paulownia Plantation  

NASA Astrophysics Data System (ADS)

Soil erosion is removal of soil and rock particles by water, wind, ice and gravity. It is widely recognized as a global soil threat. Soils impacted by different forms of erosion cover large areas around the world. While landscape, soil and climate conditions trigger soil erosion processes, the vegetation cover reduces the soil erosion risk. About 60 % of the area of agricultural land in Bulgaria is under erosion risk, which necessitates implementation of series of measures for soil erosion control. The aim of this study is to determine the erosion protection potential and the loss of soil nutrients of young Paulownia plantation. Field experiments have been set up under unirrigated conditions at the experimental field for soil erosion studies of the N. Poushkarov Institute of Soil Science, Agrotechnology and Plant Protection near Suhodol. The local soils are Chromic Luvisols, moderately eroded. The altitude is 750 m and the slope gradient is 80. The experiment consists of four field plots for soil erosion studies, three of which planted with Paulownia Bellissima and a reference one with bare soil. The plants have been planted at a distance of 2 m between adjacent rows and 1 m between each two plants within the row. The size of each field plot is 32 m2 (4 m width and 8 m length). The plots are equipped with containers for collecting the surface runoff caused by erosive rainfall events. Biometrics, including the root-striking of the plants, their growth in height, foliage cover (projection) and stem diameter, was studied from May 13th to October 21st. The data reported cover the results from the studies during the first vegetation period after planting in the Spring of 2013. During the year four erosive rainfalls were observed with a total amount of 79.2 mm, resulting to a total amount of soil loss of 772 kg/ha from a planted plot and 551 kg/ha from bear soil. The total surface runoff is 156.7 m3/ha from planted plot and 153.1 m3/ha from bare soil. The total losses of N-NO3- are 0.994 kg/ha from plated plots and 0.718 kg/ha from bare soils and the losses of N-NH4+ are respectively 0.042 and 0.117 kg/ha. The results from biometrics showed that 58 % of the plants were found to have stroken roots; an average growth of 0.3 m and a mean increase in the number of leaves with 3 were recorded. The results reported here show that the losses of soil and nutrients from the field plots planted with Paulownia Bellissima are about 40 % higher than these from the plot with bare soil. This discouraging result needs further experimental and theoretical analyses. The research throughout the following years will give further information about the soil erosion protection potential of young Paulownia plantation.

Stepchich, Avgusta; Djodjov, Christo

2014-05-01

275

Metallized viscoelastic control layers for light-valve projection displays  

Microsoft Academic Search

In the first part of the three-paper series on light-valve projection with metallized viscoelastic control layers, the technologies for producing suitable layer systems as well as the observed performance of such light modulators are described. Optimum conditions for elastomer preparation and gel-layer formation by means of spin coating are given. Before metallization in a multistep vacuum evaporation process, the elastomer

W. Brinker; W. Wirges; G. Przyrembel; R. Gerhard-Multhaupt; J. Klemberg-Sapieha; L. Martinu; D. Poitras; M. R. Wertheimer

1995-01-01

276

Finite Convergence of a Subgradient Projections Method with Expanding Controls  

SciTech Connect

We study finite convergence of the modified cyclic subgradient projections (MCSP) algorithm for the convex feasibility problem (CFP) in the Euclidean space. Expanding control sequences allow the indices of the sets of the CFP to re-appear and be used again by the algorithm within windows of iteration indices whose lengths are not constant but may increase without bound. Motivated by another development in finitely convergent sequential algorithms that has a significant real-world application in the field of radiation therapy treatment planning, we show that the MCSP algorithm retains its finite convergence when used with an expanding control that is repetitive and fulfills an additional condition.

Censor, Yair, E-mail: yair@math.haifa.ac.il [University of Haifa, Department of Mathematics (Israel); Chen Wei, E-mail: chen.wei@mgh.harvard.edu [Massachusetts General Hospital and Harvard Medical School, Department of Radiation Oncology (United States); Pajoohesh, Homeira, E-mail: hpajoohesh@mec.cuny.edu [City University of New York, Department of Mathematics, Medgar Evers College (United States)

2011-10-15

277

Assessment of Rainfall, Erosivity, Runoff and Erosion in the Area  

E-print Network

Assessment of Rainfall, Erosivity, Runoff and Erosion in the Area North and West of Mount Kenya of the road is over grazed public Maasai land, susceptible to erosion. 1 Centre for Development and Environment #12;3 Summary This study involves the analysis of rainfall, erosivity, runoff and erosion data

Richner, Heinz

278

Preventing inadmissible erosion-corrosion thinning from occurring in the diffuser segments of feedwater supply control systems of power units at nuclear power stations equipped with RBMK-1000 reactors  

NASA Astrophysics Data System (ADS)

Results obtained from investigations of erosion-corrosion processes that occur during operation of the feedwater supply control systems used in power units of nuclear power stations equipped with RBMK-1000 reactors and the sensitivity of these processes to variations in the chemical composition of metal and in the flow path geometry are presented. It is found that local erosion-corrosion thinning of the walls in the diffuser segments of feedwater supply control systems occur mainly due to intense mass transfer in the near-wall region taken in combination with a low content of chromium. Hydrodynamic simulation was carried out, and it was shown based on its results that local erosion-corrosion thinning of the walls of pipeline segments downstream of the valves controlling the supply of feedwater to power units of nuclear power stations equipped with RBMK-1000 reactors can be prevented by subjecting them to appropriate modernization. It is found that the above mentioned diffuser parts can be made more resistant to erosion-corrosion wear by keeping the content of chromium in the main metal and weld joints at a level of no less than 0.25% and concurrently reducing the hydrodynamic effect in the zones of weld connections.

Tomarov, G. V.; Shipkov, A. A.; Golubeva, T. N.; Greblov, P. N.

2013-05-01

279

Microprocessor-based monitoring and control project. Phase I report  

SciTech Connect

This report summarizes the activities of Phase I of the Microprocessor-Based Monitoring and Control Project. This project is part of an ongoing effort in the Electrical Systems Group of TVA's Division of Energy Demonstrations and Technology (ED and T) to develop microprocessor-based systems for special-purpose applications in the monitoring of power system parameters and the control and protection of power system apparatus to improve power operations. The system presently configured receives its voltage and current signals from conventional potential and current transformers. However, under a separate project, ED and T will test and evaluate electro-optic and magneto-optic voltage and current sensors for eventual use with microprocessor-based systems. This report specifically describes the initial activities performed in configuring the microprocessor-based system to monitor and compute power system parameters at the Concord 161-kV Substation. In the next phase, the system will be expanded to simulate the switching of the 46-kV capacitor banks for voltage and reactive control at the substation.

Not Available

1984-01-01

280

Weathering and Erosion  

NSDL National Science Digital Library

In this multi-station lab, learners conduct a series of experiments to explore the processes and effects of weathering and erosion. Using the results from these explorations, learners design and conduct an experiment comparing the rate of erosion in different biomes. Use this activity to teach weathering and erosion, and also to illustrate how scientists often use the results of one experiment to inspire another. This activity is intended to be conducted over multiple meetings.

Whitfield, Lise

2010-01-01

281

Greenridge Multi-Pollutant Control Project Preliminary Public Design Report  

SciTech Connect

The Greenidge Multi-Pollutant Control Project is being conducted as part of the U.S. Department of Energy's Power Plant Improvement Initiative to demonstrate an innovative combination of air pollution control technologies that can cost-effectively reduce emissions of SO{sub 2}, NO{sub x}, Hg, acid gases (SO{sub 3}, HCl, and HF), and particulate matter from smaller coal-fired electrical generating units (EGUs). The multi-pollutant control system includes a hybrid selective non-catalytic reduction (SNCR)/in-duct selective catalytic reduction (SCR) system to reduce NOx emissions by {ge}60%, followed by a Turbosorp{reg_sign} circulating fluidized bed dry scrubber system to reduce emissions of SO{sub 2}, SO{sub 3}, HCl, and HF by {ge}95%. Mercury removal of {ge}90% is also targeted via the co-benefits afforded by the in-duct SCR, dry scrubber, and baghouse and by injection of activated carbon upstream of the scrubber, as required. The technology is particularly well suited, because of its relatively low capital and maintenance costs and small space requirements, to meet the needs of coal-fired units with capacities of 50-300 MWe. There are about 440 such units in the United States that currently are not equipped with SCR, flue gas desulfurization (FGD), or mercury control systems. These smaller units are a valuable part of the nation's energy infrastructure, constituting about 60 GW of installed capacity. However, with the onset of the Clean Air Interstate Rule, Clean Air Mercury Rule, and various state environmental actions requiring deep reductions in emissions of SO{sub 2}, NO{sub x}, and mercury, the continued operation of these units increasingly depends upon the ability to identify viable air pollution control retrofit options for them. The large capital costs and sizable space requirements associated with conventional technologies such as SCR and wet FGD make these technologies unattractive for many smaller units. The Greenidge Project aims to confirm the commercial readiness of an emissions control system that is specifically designed to meet the environmental compliance requirements of these smaller coal-fired EGUs. The multi-pollutant control system is being installed and tested on the AES Greenidge Unit 4 (Boiler 6) by a team including CONSOL Energy Inc. as prime contractor, AES Greenidge LLC as host site owner, and Babcock Power Environmental Inc. as engineering, procurement, and construction contractor. All funding for the project is being provided by the U.S. Department of Energy, through its National Energy Technology Laboratory, and by AES Greenidge. AES Greenidge Unit 4 is a 107 MW{sub e} (net), 1950s vintage, tangentially-fired, reheat unit that is representative of many of the 440 smaller coal-fired units identified above. Following design and construction, the multi-pollutant control system will be demonstrated over an approximately 20-month period while the unit fires 2-4% sulfur eastern U.S. bituminous coal and co-fires up to 10% biomass. This Preliminary Public Design Report is the first in a series of two reports describing the design of the multi-pollutant control facility that is being demonstrated at AES Greenidge. Its purpose is to consolidate for public use all available nonproprietary design information on the Greenidge Multi-Pollutant Control Project. As such, the report includes a discussion of the process concept, design objectives, design considerations, and uncertainties associated with the multi-pollutant control system and also summarizes the design of major process components and balance of plant considerations for the AES Greenidge Unit 4 installation. The Final Public Design Report, the second report in the series, will update this Preliminary Public Design Report to reflect the final, as-built design of the facility and to incorporate data on capital costs and projected operating costs.

Daniel P. Connell

2009-01-12

282

Erosion and Wind Deposition  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Released 22 April 2003

Streamlined buttes and mesas are left as remnants of an erosive wind that has carried away sediments and even the rim of a small crater. Two wind directions are apparent in the buttes and mesas that cross each other at 90 degrees. Small dark dunes wind their way between the remnant towers, indicating that the work of the wind is an ongoing process.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

Image information: VIS instrument. Latitude 5.3, Longitude 350.1 East (9.9 West). 19 meter/pixel resolution.

2003-01-01

283

An investigation of the effect of hydrodynamics of flow on erosion-corrosion resistance of components of a feedwater control assembly used in power units of nuclear power plants equipped with RBMK-1000 reactors  

NASA Astrophysics Data System (ADS)

The results of computational hydrodynamic simulation of the flow of a working medium in the flow path of the feedwater control assembly used in power units of nuclear power plants (NPPs) equipped with the reactors of the RBMK-1000 type are presented It was established that the rate of control valve opening has an influence on the position of the areas of the intense local erosion-corrosion thinning of metal of the diffuser section downstream of the valve.

Tomarov, G. V.; Shipkov, A. A.; Golubeva, T. N.; Greblov, P. N.

2013-08-01

284

Impact of water control projects on fisheries resources in Bangladesh  

NASA Astrophysics Data System (ADS)

Bangladesh is a very flat delta built up by the Ganges—Brahmaputra—Meghna/Barak river systems. Because of its geographical location, floods cause huge destruction of lives and properties almost every year. Water control programs have been undertaken to enhance development through mitigating the threat of disasters. This structural approach to flood hazard has severely affected floodplain fisheries that supply the major share of protein to rural Bangladesh, as exemplified by the Chandpur Irrigation Project. Although the regulated environment of the Chandpur project has become favorable for closed-water cultured fish farming, the natural open-water fishery loss has been substantial. Results from research show that fish yields were better under preproject conditions. Under project conditions per capita fish consumption has dropped significantly, and the price of fish has risen beyond the means of the poor people, so that fish protein in the diet of poor people is gradually declining. Bangladesh is planning to expand water control facilities to the remaining flood-prone areas in the next 15 20 years. This will cause further loss of floodplain fisheries. If prices for closed-water fish remain beyond the buying power of the poor, alternative sources of cheap protein will be required.

Mirza, Monirul Qader; Ericksen, Neil J.

1996-07-01

285

The Large Synoptic Survey Telescope project management control system  

NASA Astrophysics Data System (ADS)

The Large Synoptic Survey Telescope (LSST) program is jointly funded by the NSF, the DOE, and private institutions and donors. From an NSF funding standpoint, the LSST is a Major Research Equipment and Facilities (MREFC) project. The NSF funding process requires proposals and D&D reviews to include activity-based budgets and schedules; documented basis of estimates; risk-based contingency analysis; cost escalation and categorization. "Out-of-the box," the commercial tool Primavera P6 contains approximately 90% of the planning and estimating capability needed to satisfy R&D phase requirements, and it is customizable/configurable for remainder with relatively little effort. We describe the customization/configuration and use of Primavera for the LSST Project Management Control System (PMCS), assess our experience to date, and describe future directions. Examples in this paper are drawn from the LSST Data Management System (DMS), which is one of three main subsystems of the LSST and is funded by the NSF. By astronomy standards the LSST DMS is a large data management project, processing and archiving over 70 petabyes of image data, producing over 20 petabytes of catalogs annually, and generating 2 million transient alerts per night. Over the 6-year construction and commissioning phase, the DM project is estimated to require 600,000 hours of engineering effort. In total, the DMS cost is approximately 60% hardware/system software and 40% labor.

Kantor, Jeffrey P.

2012-09-01

286

Scales and erosion  

Technology Transfer Automated Retrieval System (TEKTRAN)

There is a need to develop scale explicit understanding of erosion to overcome existing conceptual and methodological flaws in our modelling methods currently applied to understand the process of erosion, transport and deposition at the catchment scale. These models need to be based on a sound under...

287

WEPS and WEPP Science Commonality Project1  

Microsoft Academic Search

The United States Department of Agriculture, Agricultural Research Service (USDA-ARS) has two independently developed, daily time step, process-based erosion models, one targeted for wind erosion (WEPS - Wind Erosion Prediction System) and one targeted for water erosion (WEPP - Water Erosion Prediction Project). The models currently share little source code or soil, plant, management and climate databases but do simulate

F. A. Fox; D. C. Flanagan; L. E. Wagner; L. Deer-Ascough

288

Benchmark Soilscapes to Predict Effects of Climatic Change in the Western USA: A collaborative project among western soil scientists and  

E-print Network

forming processes and ecosystem services such as air and water purification, stabilization against erosion and water purification, stabilization against erosion, flood control, carbon storage and regulation project among western soil scientists and the USDA Natural Resources Conservation Service Jay B. Norton

Norton, Jay B.

289

Project B610 process control configuration acceptance test report  

SciTech Connect

The purpose of this test is to verify the Westinghouse configuration of the MICON A/S Distributed Control System for project B610. The following will be verified: (1) proper assignment and operation of all field inputs to and outputs from the MICON Termination panels; (2) proper operation of all display data on the operators` console; (3) proper operation of all required alarms; and (4) proper operation of all required interlocks. This test only verifies the proper operation of the Westinghouse control configuration (or program). It will not be responsible for verifying proper operation of the MICON hardware or operating software. Neither does it test any of the B610 instrument. The MICON hardware and software has been tested as part of the equipment procurement. Instrumentation and wiring installed under project B620 will be tested under a separate functional test. In some cases, precise transmitter ranges, alarm setpoints, and controller tuning parameters are not available at this time. Therefore, approximate values are used during the test. This should not affect the proper operation of the configuration or the validity of this test. Final values will be assigned during operability testing.

Silvan, G.R.

1995-06-27

290

CRCHD SPN Project: The Network for Cancer Control Research Among American Indian and Alaska Native Populations  

Cancer.gov

CRCHD SPN Project: The Network for Cancer Control Research Among American Indian and Alaska Native Populations  Back to CRCHD Completed Research SPN Project Listing The Network for Cancer Control Research Among American Indian and Alaska Native

291

CRCHD SPN Project: National Black Leadership-Cancer Control, Research & Training Network  

Cancer.gov

CRCHD SPN Project: National Black Leadership-Cancer Control, Research & Training Network  Back to CRCHD Completed Research SPN Project Listing National Black Leadership-Cancer Control, Research & Training Network National Black Leadership-Cancer

292

Rainfall erosivity in Europe.  

PubMed

Rainfall is one the main drivers of soil erosion. The erosive force of rainfall is expressed as rainfall erosivity. Rainfall erosivity considers the rainfall amount and intensity, and is most commonly expressed as the R-factor in the USLE model and its revised version, RUSLE. At national and continental levels, the scarce availability of data obliges soil erosion modellers to estimate this factor based on rainfall data with only low temporal resolution (daily, monthly, annual averages). The purpose of this study is to assess rainfall erosivity in Europe in the form of the RUSLE R-factor, based on the best available datasets. Data have been collected from 1541 precipitation stations in all European Union (EU) Member States and Switzerland, with temporal resolutions of 5 to 60min. The R-factor values calculated from precipitation data of different temporal resolutions were normalised to R-factor values with temporal resolutions of 30min using linear regression functions. Precipitation time series ranged from a minimum of 5years to a maximum of 40years. The average time series per precipitation station is around 17.1years, the most datasets including the first decade of the 21st century. Gaussian Process Regression (GPR) has been used to interpolate the R-factor station values to a European rainfall erosivity map at 1km resolution. The covariates used for the R-factor interpolation were climatic data (total precipitation, seasonal precipitation, precipitation of driest/wettest months, average temperature), elevation and latitude/longitude. The mean R-factor for the EU plus Switzerland is 722MJmmha(-1)h(-1)yr(-1), with the highest values (>1000MJmmha(-1)h(-1)yr(-1)) in the Mediterranean and alpine regions and the lowest (<500MJmmha(-1)h(-1)yr(-1)) in the Nordic countries. The erosivity density (erosivity normalised to annual precipitation amounts) was also the highest in Mediterranean regions which implies high risk for erosive events and floods. PMID:25622150

Panagos, Panos; Ballabio, Cristiano; Borrelli, Pasquale; Meusburger, Katrin; Klik, Andreas; Rousseva, Svetla; Tadi?, Melita Per?ec; Michaelides, Silas; Hrabalíková, Michaela; Olsen, Preben; Aalto, Juha; Lakatos, Mónika; Rymszewicz, Anna; Dumitrescu, Alexandru; Beguería, Santiago; Alewell, Christine

2015-04-01

293

Splash erosion. A bibliometric Review  

NASA Astrophysics Data System (ADS)

Ellison (1944) developed the splash board as a system for measuring splash erosion that was both cheap and reliable. Bollinne (1975), Morgan (1978, 1981). Mutchler (1967) described another different type of splash detectors according to whether they were passive or could register data. In the study mentioned above these authors included bottles, funnels, glasses, photography, markers. After that several devices has been made up like the splash sampler (Leguedois et al., 2005), soil tray (Van Dijk et al., 2002), splash funnel (Terry, 1989) and several rain cups (Fernandez-Raga et al., 2010; Molina and Llinares, 1996; Torri et al., 1987). Splash erosion research has materialized in the form of a number of papers published in international journals. The database of bibliographic references employed has been one of the most prestigious ones: theWeb of Science (ISI). The search was carried out on January 27th 2012. Among the 3x10^8 scholarly documents included in the Science Citation Index Expanded (SCI-EXPANDED) 1899 to present , the searching engine located 439 containing the word "splash erosion*", where the asterisk acts as a wildcard for any letter or group of letters. Of these, 383 were classified as articles, 87 as proceeding papers, 5 as editorial material, 2 as notes and 1 as correction. These documents have been published in 163 different journals, although four are particularly recurrent: Earth surface processes and Landforms, Catena, Soil Science Society of America Journal and Hydrological processes, with 41, 35, 35 and 26 published documents respectively. A geographic analysis of these articles has been carried out in an attempt to determine in what parts of the world research projects were making use of splash erosion. The results are that anglo-saxon countries, as USA, England and Australia dominate, particularly USA, with 130 articles. China and Japan are large communities of researches too, and some Central European countries as Belgium, France Germany and Netherlands. It is interesting to analyze the evolution of research by means of splash erosion publications. Figure 6 shows the number of documents published every decade from 1961 (the first publication appears in 1967) . Various aspects need to be commented: • The decades show an exponential increase in the number of publications. • The line in the figure represents the rise in the number of publications, which have been larger in the last two decades (900s and 20000s). • The last decade included began in 2001 leads us to predict a strong boost in research in this particular field. It is also worthwhile to consider briefly the main concepts dealt with in the documents published: • There are only 3 publications with disdrometer + splash erosion as topic words. • After 1991 and 2000 we find that there are several lines of measurement of two main research lines today are already defined: the study of the splash produces with rain simulation processes or splash produces with natural rain (relationship with atmospheric variables and accuracy of the measurements). • The current decade is characterized by an increase in research using disdrometers for studying splash erosion. Summing up, the research that is being carried out using splash erosion is evolving towards an increasing number of projects, countries, and especially, papers published in prestigious scientific journals.

Fernández Raga, M. B.

2012-04-01

294

Analysis/control of in-bed tube erosion phenomena in the fluidized bed combustion (FBC) system. Technical progress report No. 8, July 1994--September 1994  

SciTech Connect

This technical report summarizes the research work performed and progress achieved during the period of July 1, 1994 to September 30, 1994. The metal wastage of AISI 1018 low carbon steel at different particle velocity was discussed to understand the erosion phenomena of in-bed tube in FBC system. At both low velocity (2.5 m/s) and high (30 m/s), the maximum metal wastage was occurred at 45{degrees} of impact angle. The erosion rates at low particle velocity were two (2) to three (3) orders of magnitude lower than those at high particle velocity. The characteristics of anti-erosion and design considerations were discussed and suggested for some basic design guidelines, which might be important to the designer of bubbling fluidized combustors. The working principle and mechanism of anti-erosion devices will be discussed. Based upon the understanding of the working principle and mechanism of anti-erosion devices, different types of ant-erosion tube will be designed for the cold model bench-scale FBC system.

Lee, S.W.

1994-10-01

295

Potential for monitoring soil erosion features and soil erosion modeling components from remotely sensed data  

NASA Technical Reports Server (NTRS)

Accurate estimates of soil erosion and its effects on soil productivity are essential in agricultural decision making and planning from the field scale to the national level. Erosion models have been primarily developed for designing erosion control systems, predicting sediment yield for reservoir design, predicting sediment transport, and simulating water quality. New models proposed are more comprehensive in that the necessary components (hydrology, erosion-sedimentation, nutrient cycling, tillage, etc.) are linked in a model appropriate for studying the erosion-productivity problem. Recent developments in remote sensing systems, such as Landsat Thematic Mapper, Shuttle Imaging Radar (SIR-B), etc., can contribute significantly to the future development and operational use of these models.

Langran, K. J.

1983-01-01

296

Issues of upscaling in space and time with soil erosion models  

NASA Astrophysics Data System (ADS)

Soil erosion - the entrainment, transport and deposition of soil particles - is an important phenomenon to understand; the quantity of soil loss determines the long term on-site sustainability of agricultural production (Pimental et al., 1995), and has potentially important off-site impacts on water quality (Bilotta and Brazier, 2008). The fundamental mechanisms of the soil erosion process have been studied at the laboratory scale, plot scale (Wainwright et al., 2000), the small catchment scale (refs here) and river basin scale through sediment yield and budgeting work. Subsequently, soil erosion models have developed alongside and directly from this empirical work, from data-based models such as the USLE (Wischmeier and Smith, 1978), to ‘physics or process-based' models such as EUROSEM (Morgan et al., 1998) and WEPP (Nearing et al., 1989). Model development has helped to structure our understanding of the fundamental factors that control soil erosion process at the plot and field scale. Despite these advances, however, our understanding of and ability to predict erosion and sediment yield at the same plot, field and also larger catchment scales remains poor. Sediment yield has been shown to both increase and decrease as a function of drainage area (de Vente et al., 2006); the lack of a simple relationship demonstrates complex and scale-dependant process domination throughout a catchment, and emphasises our uncertainty and poor conceptual basis for predicting plot to catchment scale erosion rates and sediment yields (Parsons et al., 2006b). Therefore, this paper presents a review of the problems associated with modelling soil erosion across spatial and temporal scales and suggests some potential solutions to address these problems. The transport-distance approach to scaling erosion rates (Wainwright, et al., 2008) is assessed and discussed in light of alternative techniques to predict erosion across spatial and temporal scales. References Bilotta, G.S. and Brazier, R.E., 2008. Understanding the influence of suspended solids on water quality and aquatic biota. Water Research, 42(12): 2849-2861. de Vente, J., Poesen, J., Bazzoffi, P., Van Ropaey, A.V. and Verstraeten, G., 2006. Predicting catchment sediment yield in Mediterranean environments: the importance of sediment sources and connectivity in Italian drainage basins. Earth Surface Processes And Landforms, 31: 1017-1034. Morgan, R.P.C. et al., 1998. The European soil erosion model (EUROSEM): a dynamic approach for predicting sediment transport from fields to small catchments. Earth Surface Processes And Landforms, 23: 527-544. Nearing, M. A., G. R. Foster, L. J. Lane, and S. C. Finkner. 1989. A process-based soil erosion model for USDA Water Erosion Prediction Project technology. Trans. ASAE 32(5): 1587-1593. Parsons, A.J., Brazier, R.E., Wainwright, J. and Powell, D.M., 2006a. Scale relationships in hillslope runoff and erosion. Earth Surface Processes and Landforms, 31(11): 1384-1393. Parsons, A.J., Wainwright, J., Brazier, R.E. and Powell, D.M., 2006b. Is sediment delivery a fallacy? Earth Surface Processes and Landforms, 31(10): 1325-1328. Pimental, D. et al., 1995. Environmental and economic costs of soil erosion and conservation benefits. Science, 267:1117-1122. Wainwright, J., Parsons, A.J. and Abrahams, A.D., 2000. Plot-scale studies of vegetation, overland flow and erosion interactions: case studies from Arizona and New Mexico. Hydrological Processes, 14(16-17): 2921-2943. Wischmeier, W.H. and Smith, D.D., 1978. Predicting rainfall erosion losses - a guide for conservation planning., 537.

Brazier, R. E.; Parsons, A. J.; Wainwright, J.; Hutton, C.

2009-04-01

297

Erosion dynamics of a wet granular medium  

NASA Astrophysics Data System (ADS)

Liquid may give strong cohesion properties to a granular medium, and confer a solidlike behavior. We study the erosion of a fixed circular aggregate of wet granular matter subjected to a flow of dry grains inside a half-filled rotating drum. During the rotation, the dry grains flow around the fixed obstacle. We show that its diameter decreases linearly with time for low liquid content, as wet grains are pulled out of the aggregate. This erosion phenomenon is governed by the properties of the liquids. The erosion rate decreases exponentially with the surface tension while it depends on the viscosity to the power -1. We propose a model based on the force fluctuations arising inside the flow, explaining both dependencies: The capillary force acts as a threshold and the viscosity controls the erosion time scale. We also provide experiments using different flowing grains, confirming our model.

Lefebvre, Gautier; Jop, Pierre

2013-09-01

298

Erosion dynamics of a wet granular medium  

E-print Network

Liquid may give strong cohesion properties to a granular medium, and confer a solid-like behavior. We study the erosion of a fixed circular aggregate of wet granular matter subjected to a flow of dry grains inside a half-filled rotating drum. During the rotation, the dry grains flow around the fixed obstacle. We show that its diameter decreases linearly with time for low liquid content, as wet grains are pulled-out of the aggregate. This erosion phenomenon is governed by the properties of the liquids. The erosion rate decreases exponentially with the surface tension while it depends on the viscosity to the power -1. We propose a model based on the force fluctuations arising inside the flow, explaining both dependencies: the capillary force acts as a threshold and the viscosity controls the erosion time scale. We also provide experiments using different flowing grains confirming our model.

Gautier Lefebvre; Pierre Jop

2014-12-08

299

Seepage Erosion Impacts on Edge-of-Field Gully Erosion  

Technology Transfer Automated Retrieval System (TEKTRAN)

Studies have found that the dominant source of sediment in streams can be from bank erosion. Subsurface flow contributes directly to bank failure by seepage erosion and soil-pipe erosion and indirectly by the impact of increased soil water pressures on loss of soil shear strength. Seepage erosion in...

300

Naked Dirt: Erosion  

NSDL National Science Digital Library

This file explains that the United States Department of Agriculture developed the Universal Soil Loss Equation (revised in 1993 to RUSLE) to help farmers, landscapers, and architects decide how to prevent erosion. The equation predicts the rate of erosion for a site based on the annual rainfall, soil type, and degree of slope. The site includes a table that shows how different practices affect erosion rates. It explains that sediment pollution makes swimming and boating less fun, clogs city drinking water systems, fills in lakes, and smothers fish and insect habitat. Sediments often float awhile before settling out, making water cloudy or turbid. There is an explanation of which native grasses are best for holding the soil in place and other suggestions to stop erosion.

301

Weathering and Erosion  

NSDL National Science Digital Library

This unit provides an introduction for younger students to the concepts of weathering and erosion. Topics include types of weathering (physical versus chemical), rates of weathering, and weathering products (soil). The section on erosion explains the importance of water and gravity in the process, and discusses some of the more important erosional agents such as wind, water and ice, streams and glaciers. A vocabulary list and downloadable, printable student worksheets are provided.

Medina, Philip

2010-09-07

302

Ice Cream Erosion  

NSDL National Science Digital Library

This demonstration will help students identify and describe the process of erosion and transfer this knowledge from class exercises to real world examples. The teacher will explain the demonstration and how it depicts the process of erosion; students will make predictions about what will happen when hot chocolate is poured over ice cream, and record their predictions as well as their observations of what happens.

303

Wear: Corrosion and erosion  

NASA Technical Reports Server (NTRS)

The various forms of corrosion are discussed and the role of localized electrochemical reactions in the wear of sliding surfaces are considered. It is stated that there is evidence that fretting corrosion, stress corrosion cracking, corrosion fatigue, and erosion corrosion have as a common basis the localized electrochemical reactions caused by a combination of the induced homogeneity of the surfaces and the corrosive environment. Several processes leading to erosive wear are discussed.

Rowe, C. N.

1973-01-01

304

Analysis/control of in-bed tube erosion phenomena in the fluidized bed combustion (FBC) system. Technical progress report No. 14, [January 1, 1996--March 31, 1996  

SciTech Connect

The material wastage tests were continued to analyze erosion phenomena under the simulated erosion conditions of in-bed tubes in fluidized bed combustors. AISI 1018 steel and three thermal sprayed coating specimens were tested at an elevated temperature (300{degrees}C) using nozzle type erosion tester. Bed ashes retrieved from the operating biomass-fired boiler were used for erodent particles at a particle loading of 375 g, at particle impact angle of 30{degrees}, at particle velocity 60 m/s for exposure periods of 4 hours. The specimens were water-cooled on the backside. The material wastage of specimens was determined by thickness measurements. Test results can be seen that the cooled specimen had greater material wastage than that of the uncooled specimens. In addition, all of thermal-sprayed coating specimens for both cooled and uncooled specimens could reduce the erosion wastage rates as compared with 1018 steel. Among the three thermal-sprayed coatings, a DS-105 specimen of high velocity oxygen fuel spraying exhibited the lowest erosion wastage rate. When tested a higher particle velocity (60 m/s), but at the same elevated temperature (300{degrees}C), the material wastage rate of all three coatings was about 6 to 18 times higher than that of the material wastage at a low particle velocity (2.5 m/s).

Lee, Seong W.

1996-04-01

305

Integrated Project Scheduling and Staff Assignment with Controllable Processing Times  

PubMed Central

This paper addresses a decision problem related to simultaneously scheduling the tasks in a project and assigning the staff to these tasks, taking into account that a task can be performed only by employees with certain skills, and that the length of each task depends on the number of employees assigned. This type of problems usually appears in service companies, where both tasks scheduling and staff assignment are closely related. An integer programming model for the problem is proposed, together with some extensions to cope with different situations. Additionally, the advantages of the controllable processing times approach are compared with the fixed processing times. Due to the complexity of the integrated model, a simple GRASP algorithm is implemented in order to obtain good, approximate solutions in short computation times. PMID:24895672

Framinan, Jose M.

2014-01-01

306

Management of a large distributed control system development project  

SciTech Connect

Building an accelerator at six geographically dispersed sites is quite mad, but politically expedient. The Spallation Neutron Source (SNS), currently under construction in Oak Ridge, Tennessee, combines a pulsed 1 Gev H{sup -} superconducting linac with a compressor ring to deliver 2 MW of beam power to a liquid mercury target for neutron production [1]. Accelerator components, target and experimental (neutron-scattering) instruments are being developed collaboratively by Lawrence Berkeley (Ion Source and Front End), Los Alamos (Linac), Thomas Jefferson (Cryosystems), Brookhaven (Compressor Ring), Oak Ridge (Target and Conventional Facilities) and Argonne (Neutron Scattering Instruments) National Laboratories. Similarly, a team distributed among all of the participating laboratories is developing the EPICS-based control system. this paper discusses the management model and strategies being used to address the unusual issues of organization, communication, standardization, integration and hand-off inherent in this widely-distributed project.

Gurd, D. P. (David P.)

2002-01-01

307

23 CFR 751.23 - Concurrent junkyard control and right-of-way projects.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Concurrent junkyard control and right-of-way projects...RIGHT-OF-WAY AND ENVIRONMENT JUNKYARD CONTROL AND ACQUISITION § 751.23 Concurrent junkyard control and right-of-way...

2010-04-01

308

EVALUATING WEPP-PREDICTED INFILTRATION RUNOFF AND SOIL EROSION FOR FURROW IRRIGATION  

Microsoft Academic Search

The Water Erosion Prediction Project (WEPP) model contains a furrow irrigation component,to simulate hydrology and erosion in irrigation furrows. It currently is the only multiple-event furrow erosion simulation model available for public use. However, the furrow irrigation component has not been evaluated yet. Therefore, we evaluated the WEPP model for furrow irrigation by comparing predicted infiltration, runoff, and soil loss

D. L. Bjorneberg; T. J. Trout; R. E. Sojka; J. K. Aase

1999-01-01

309

Assessment of Soil Erosion at a DC Park Facility Spring Valley Park  

E-print Network

1 Assessment of Soil Erosion at a DC Park Facility Spring Valley Park NW Washington, DC Annual of this project is to provide a preliminary site inventory and assessment of soil erosion for the Spring Valley erosion. Due to its location relative to the University and small size it was determined to be an ideal

District of Columbia, University of the

310

Mike Domenik Rinderknecht 1 | 1 Student Project Force Control of Linear Brushless  

E-print Network

Mike Domenik Rinderknecht 1 | 1 Student Project ­ Force Control of Linear Brushless DC Motor. Project Description The main part of the project will consist in the selection of adequate driving be implemented in LabVIEW. Tasks 10% Literature review of state of the art in control for BLDC motors 30

Daraio, Chiara

311

MEM 639 Real-time Microcomputer Control 1 Project Copyright by Paul Oh, 2007  

E-print Network

MEM 639 Real-time Microcomputer Control 1 Project © Copyright by Paul Oh, 2007 Project: 5-Page and control theory. For software skills, primers in LabVIEW programming were provided. For hardware, analog the tools and knowledge to begin and complete the course objective. This Project (worth 25% of one's final

Oh, Paul

312

Ecological site-based assessments of wind and water erosion: informing accelerated soil erosion management in rangelands  

USGS Publications Warehouse

Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explore how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass-succulent states across the ecological sites at the plot scale (0.25 Ha). We identify vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area can be effectively controlled when bare ground cover is 100 cm in length is less than ~35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the development of practical management solutions.

Webb, Nicholas P.; Herrick, Jeffrey E.; Duniway, Michael C.

2014-01-01

313

The threat of soil erosion to long-term crop production  

Microsoft Academic Search

National increases in row crops at the expense of hay and pasture crops, particularly on steeper slopes, have made the control of erosion a difficult prospect. Management practices that fit the various field conditions are needed to accomplish effective erosion control. These measures should be selected on the basis of soil characteristics, landscape type, and the amount of ongoing erosion.

W. E. Larson; F. J. Pierce; R. H. Dowdy

1983-01-01

314

Hydro-abrasive erosion: Problems and solutions  

NASA Astrophysics Data System (ADS)

The number of hydro power plants with hydro-abrasive erosion is increasing worldwide. An overall approach is needed to minimize the impact of this phenomenon. Already at the start of the planning phase an evaluation should be done to quantify the erosion and the impact on the operation. For this, the influencing parameters and their impact on the erosion have to be known. The necessary information for the evaluation comprises among others the future design, the particle parameters of the water, which will pass the turbine, and the power plant owner's framework for the future operation like availability or maximum allowable efficiency loss, before an overhaul needs to be done. Based on this evaluation of the erosion, an optimised solution can then be found, by analysing all measures in relation to investments, energy production and maintenance costs as decision parameters. Often a more erosion-resistant design, instead of choosing the turbine design with the highest efficiency, will lead to higher revenue. The paper will discuss the influencing parameters on hydro-abrasive erosion and the problems to acquire this information. There are different optimisation possibilities, which will be shown in different case studies. One key aspect to reduce the erosion and prolong the operation time of the components is to coat all relevant parts. But it is very important that this decision is taken early in the design stage, as the design has to be adapted to the requirements of the coating process. The quality of coatings and their impact on the operation will be discussed in detail in the paper as due to the non-availability of standards many questions arise in projects.

Winkler, K.

2014-12-01

315

9 CFR 54.9 - Waiver of requirements for scrapie control pilot projects.  

Code of Federal Regulations, 2010 CFR

...determination that an animal is a high-risk animal, if the scrapie control...project plan contains testing or other procedures that indicate that an animal, despite meeting the...project plan contains alternative procedures to...

2010-01-01

316

9 CFR 79.7 - Waiver of requirements for scrapie control pilot projects.  

Code of Federal Regulations, 2010 CFR

...determination that an animal is a high-risk animal, if the scrapie control...project plan contains testing or other procedures that indicate that an animal, despite meeting the...project plan contains alternative procedures to...

2010-01-01

317

A wood-strand material for wind erosion control: effects on total sediment loss, PM10 vertical flux, and PM10 loss  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wind erosion is a widespread problem in much of the western United States due to arid conditions and persistent winds. Fugitive dust emitted from eroding land poses a risk to both environmental quality and human health. The Clean Air Act, established in 1971, was revised in 1987 to include ambient a...

318

Particulate erosion mechanisms  

NASA Technical Reports Server (NTRS)

Particulate damage and erosion of ductile metals are today plaguing design and field engineers in diverse fields of engineering and technology. It was found that too many models and theories were proposed leading to much speculation from debris analysis and failure mechanism postulations. Most theories of solid particle erosion are based on material removal models which do not fully represent the actual physical processes of material removal. The various mechanisms proposed thus far are: melting, low-cycle fatigue, extrusion, delamination, shear localization, adhesive material transfer, etc. The experimental data on different materials highlighting the observed failure modes of the deformation and cutting wear processes using optical and scanning electron microscopy are presented. The most important mechanisms proved from the experimental observations of the specimens exposed to both spherical and angular particles are addressed, and the validity of the earlier theories discussed. Both the initial stages of damage and advanced stages of erosion were studied to gain a fundamental understanding of the process.

Veerabhadrarao, P.; Buckley, D. H.

1983-01-01

319

Controlled ecological life support system breadboard project, 1988  

NASA Technical Reports Server (NTRS)

The Closed Ecological Life Support System (CELSS) Breadboard Project, NASA's effort to develop the technology required to produce a functioning bioregenerative system, is discussed. The different phases of the project and its current status are described. The relationship between the project components are shown, and major project activities for fiscal years 1989 to 1993 are listed. The Biomass Production Chamber (BPC) became operational and tests of wheat as a single crop are nearing completion.

Knott, W. M.

1990-01-01

320

[Erosive hand osteoarthritis].  

PubMed

Erosive hand osteoarthritis is common and debilitating. Diagnosis is based on the presence of bone erosions which can appear late. Ultrasonography allows earlier diagnosis. The presence of apatite deposits could be of poor prognosis. Non pharmacological treatment includes the explanation of the inflammatory phenomena involved and the use of splints and physical therapy. Drug therapy includes analgesics, NSAIDs and infiltration of a steroid. Chondroitin sulfates have an analgesic and functional effect proven. DMARDs such as hydroxychloroquine and methotrexate have been used successfully. Some patients also benefited from isotope synoviortheses. New therapeutic ways, based on the pathophysiology of the disease, are new under evaluation. PMID:23534244

Van Linthoudt, D; Gabay, C; So, A K L

2013-03-13

321

River Flooding and Erosion  

NSDL National Science Digital Library

Students are presented with a real-life problem of flooding and erosion in the town of Simonton. They must use historical dischage data to determine the future risk of flooding. They must also use historical map data to asses the risk of future losses due to erosion. Using these data, they must dertermine the feasibility of levee systems proposed by the Corp of Engineers. Lastly, they must discuss their assumption and possible sources of error. Has minimal/no quantitative component Uses geophysics to solve problems in other fields

Dupre, Bill

322

Wind Erosion in Tithonium  

NASA Technical Reports Server (NTRS)

30 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows wind-eroded sedimentary rocks in Tithonium Chasma, one of the troughs of the Valles Marineris system. The winds responsible for the majority of the erosion blew from the northeast (upper right), creating yardangs (wind erosion ridges) with their tapered ends pointing downwind.

Location near: 4.6oS, 88.3oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Winter

2005-01-01

323

Erosion effects on TVC vane heat transfer characteristics  

Microsoft Academic Search

This work describes the effects of erosion on the heat transfer characteristics on thrust vector control vanes exposed to aluminized propellant exhaust flows. This was accomplished using an inverse heat transfer parameter identification of quarter scale models. The model is based on a four node lumped parameter system with two heat energy inputs. The erosion is modeled as decreasing the

Steven R. Gardner

1994-01-01

324

Climate Change Effects on the Sacramento Basin's Flood Control Projects ANN DENISE FISSEKIS  

E-print Network

Climate Change Effects on the Sacramento Basin's Flood Control Projects By ANN DENISE FISSEKIS B.......................................................................6 Chapter III. Climate Change................................................................11 models...........................................................20 Climate change data

Lund, Jay R.

325

Bioengineering applied to erosion and stability control in the North Apennines (Emilia-Romagna Region, Italy): a check about critical aspects of the works.  

NASA Astrophysics Data System (ADS)

Because of its geological structure, in the Emilia-Romagna Region over 32,000 landslides have been identified. Several works have been made in order to control mass movement's dynamics and to secure of Reno and Lamone Mountain Basin Rivers, the road network and near by villages and towns. Most of the control works dealt with bioengineering practices: palisades piles, geotextiles, seedings, surface flow control works, dikes within main drainage ditches. In order to check about critical aspects related to the use of these techniques in the Apennines, a survey in this basins was designed with specific interest in the several kinds of works realised, in which plant species were mostly used and in the factors that affected the success or failure of the works. Territory encompasses steep slopes covered with woods to low reliefs covered with grasslands. It is characterized by prevailing clays, inducing instability, and arenaceous lithology with impermeable soils; drainage density is quite high and hillsides suffer extensive and severe erosion and slope stability problems. Chestnut woods mainly represent land use at higher altitudes, while coppice, pastures and crops are present on milder hillsides. The remaining part of the basin is covered by vineyards, orchards, ponds and urban areas, which are basically located in the valley floor. Precipitation events mainly consist of rainfall ranging between 950-1015 mm per year; few snowfalls occur during winter and a long dry season lasts from June until September. We have analyzed 187 works designed mainly for the consolidation of slope instabilities through a widespread enhancement of the vegetation cover. The surveyed works are classified as a function of their building features: it can be seen that cribwalls and palisades are by far the most common types, being the 24% and the 34% respectively of the works. As far as the most adopted plant species, they were silver willow (Salix alba), Spanish Broom (Spartium Junceum) and purple willow (Salix purpurea). Only the 25% of the interventions was accomplished by the use of secondary plant species, as tamarisk (Tamarix spp.,) blackthorn (Prunus spinosa) , whitethorn (Crataegus spp.), sea-buckthorn (Hipphopae rhamnoides), wild pear (Pyrus pyraster), cottonwood (Populus nigra), eglantine (Rosa spp.), goat-willow (Salix caprea) and cornel (Cornus sanguinea). Better results were achieved with Spanish Broom, a very rural plant that can effectively colonise even poor soils like badlands; as a matter of fact, more than the 75% of the interventions had positive outcomes The efficacy of the consolidation work by the presence of living structures point out an increase of the stability of those interventions older than 4 years, with taking root species present from 54% to 78%. So far, the construction and the reliability of the works have been monitored, in order to capture critical aspects for the success of works and to build a geo-referenced data base of the existing works and their status.

Selli, Lavinia; Cavazza, Claudio; Pavanelli, Donatella

2013-04-01

326

Guidance and Control Software Project Data - Volume 4: Configuration Management and Quality Assurance Documents  

NASA Technical Reports Server (NTRS)

The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes configuration management and quality assurance documents from the GCS project. Volume 4 contains six appendices: A. Software Accomplishment Summary for the Guidance and Control Software Project; B. Software Configuration Index for the Guidance and Control Software Project; C. Configuration Management Records for the Guidance and Control Software Project; D. Software Quality Assurance Records for the Guidance and Control Software Project; E. Problem Report for the Pluto Implementation of the Guidance and Control Software Project; and F. Support Documentation Change Reports for the Guidance and Control Software Project.

Hayhurst, Kelly J. (Editor)

2008-01-01

327

External Resource: Weathering and Erosion  

NSDL National Science Digital Library

This activity includes background information about weathering, as well as simple demonstrations/activities to model how weather conditions contribute to weathering and erosion. Topics include: chemical weathering, dunes, erosion, floods, glaciers, physi

1900-01-01

328

External Resource: Erosion and Weathering  

NSDL National Science Digital Library

This is a Teachers' Domain photo essay with images that depict surface features on Earth that result from weathering and erosion, as well as measures designed to mitigate their unwanted effects. Topics: weathering, erosion, sediments, dunes, deltas, glaci

1900-01-01

329

Glacier Goo Erosion Experiments  

NSDL National Science Digital Library

Using a glacier proxy, students design an experiment to connect glacial erosion with glacial flow. Students choose from a variety of materials, determined what question they want their experiment or experiments to answer, design the procedure, test the experiment, and write up a lab report on the experiment.

Rachel Headley

330

Erosion of dust aggregates  

E-print Network

Aims: The aim of this work is to gain a deeper insight into how much different aggregate types are affected by erosion. Especially, it is important to study the influence of the velocity of the impacting projectiles. We also want to provide models for dust growth in protoplanetary disks with simple recipes to account for erosion effects. Methods: To study the erosion of dust aggregates we employed a molecular dynamics approach that features a detailed micro-physical model of the interaction of spherical grains. For the first time, the model has been extended by introducing a new visco-elastic damping force which requires a proper calibration. Afterwards, different sample generation methods were used to cover a wide range of aggregate types. Results: The visco-elastic damping force introduced in this work turns out to be crucial to reproduce results obtained from laboratory experiments. After proper calibration, we find that erosion occurs for impact velocities of 5 m/s and above. Though fractal aggregates as ...

Seizinger, Alexander; Kley, Wilhelm

2013-01-01

331

SOIL EROSION IN TEPETATES  

Technology Transfer Automated Retrieval System (TEKTRAN)

The valley of Mexico is one of the most populous places on earth. Although rainfall is low and infrequent, there is considerable soil erosion by water and land destruction due to high intensity storms, steep slopes, highly erodible volcanic derived soils and disturbance by man. The disturbance by ...

332

EROSION OF EARTH SPILLWAYS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Natural Resources Conservation Service (NRCS) Water Resources Site Analyses computer program, Sites, contains a vegetated earth spillway erosion prediction model. Since the beta release of Sites in 1996, the program has been successfully applied in the analysis of a number of existing spillways...

333

Soil Erosion by Water  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soil erosion by water, the wearing away of the earth's surface by the forces of water and gravity, consists of rock or soil particle dislodgement, entrainment, transport, and deposition. This sequence of events occurs over a wide range of temporal and spatial scales, from raindrop splash moving par...

334

Erosion of polyurethane insulation.  

NASA Technical Reports Server (NTRS)

Detailed description of the test program in which erosion of the spray foam insulation used in the S-II stage of the Saturn-V Apollo launch vehicle was investigated. The behavior of the spray foam was investigated at the elevated temperature and static pressure appropriate to the S-II stage environment, but in the absence of the aerodynamic shear stress.

Kraus, S.

1973-01-01

335

Erosion on a line  

NASA Astrophysics Data System (ADS)

An erosion model is proposed to calculate erosion rates for plane-strain models in which the Earth's surface is represented on a line. The fundamentals of river erosion networks are captured by two principles, Hack's Law, which describes the drainage area structure of river network and a stream-power erosion law, which describes the rate of incision of a river. For a simple morphology of parallel transverse rivers with rectangular drainage basins, this allows the earth's surface to be parameterized by two heights: the trunk stream channel height and the interfluvial ridge height. The resulting expressions are solved for the simple cases of constant uplift rate and a constant mean slope as occurs in critical wedge problems. In the latter case, the uplift rate is variable and changes in space so that the trunk channel elevation and the interfluvial ridge elevation average to maintain a constant mean slope. A general, numerical solution is presented for application to any numerical model with arbitrary surface velocity, variable rock erodibility and precipitation. This algorithm is coupled to a plane-strain, plastic-deformation model to demonstrate the utility of the model.

Willett, Sean D.

2010-03-01

336

Erosion processes by  

Microsoft Academic Search

The abandoned land in semiarid Mediterranean regions, with low productivity, is an obvious fact for several decades. In humid regions and with good soil, the abandoned lands, from an erosion point of view, can be seen as beneficial, as it quickly develops a major vegetation cover that protects the soil. However, in semiarid regions, with a shortage of rain and

A. Romero Diaz; J. D. Ruiz Sinoga; P. Marin Sanleandro; A. Martinez Soriano

2009-01-01

337

Predicting soil erosion for alternative land uses.  

PubMed

The APEX (Agricultural Policy-Environmental eXtender) model developed in the United States was calibrated for northwestern China's conditions. The model was then used to investigate soil erosion effects associated with alternative land uses at the ZFG (Zi-Fang-Gully) watershed in northwestern China. The results indicated that the APEX model could be calibrated reasonably well (+/-15% errors) to fit those areas with >50% slope within the watershed. Factors being considered during calibration include runoff, RUSLE (Revised Universal Soil Loss Equation) slope length and steepness factor, channel capacity flow rate, floodplain saturated hydraulic conductivity, and RUSLE C factor coefficient. No changes were made in the APEX computer code. Predictions suggest that reforestation is the best practice among the eight alternative land uses (the status quo, all grass, all grain, all grazing, all forest, half tree and half grass, 70% tree and 30% grain, and construction of a reservoir) for control of water runoff and soil erosion. Construction of a reservoir is the most effective strategy for controlling sediment yield although it does nothing to control upland erosion. For every 1 Mg of crop yield, 11 Mg of soil were lost during the 30-yr simulation period, suggesting that expanding land use for food production should not be encouraged on the ZFG watershed. Grass species are less effective than trees in controlling runoff and erosion on steep slopes because trees generally have deeper and more stable root systems. PMID:16455846

Wang, Erda; Xin, Chang; Williams, Jimmy R; Xu, Cheng

2006-01-01

338

Successful Pursuit of Small Electrical and Controls Projects by a Small Civil Engineering Firm  

E-print Network

This paper determines how a small, primarily civil engineering firm possessing an electrical and controls group can successfully pursue small electrical and controls projects issued by local electrical generation utilities. Not only...

Gates, Craig

2008-07-25

339

Vision-based Guidance and Control of Robots in Projective Andreas Ruf, et al  

E-print Network

Vision-based Guidance and Control of Robots in Projective Space Andreas Ruf, et al GRAVIR guiding and controlling a robot in projective three-space using stereo vision. As the proposed method laws fail. 1 Introduction Research in computer vision was very much driven by the robot vision problem

Paris-Sud XI, Université de

340

Know Your Enemy: The Use of Molecular Ecology in the Onopordum Biological Control Project  

Microsoft Academic Search

Experience has repeatedly shown that accurate identification of the target weed(s) for a biological control project is critical to the success of a biological control project. This is particularly true where the weed may comprise different biotypes or be part of a species complex, where hybridisation is suspected or where the agent - host plant relationship is very tight. Molecular

P. C. O'HANLON; D. T. BRIESE; R. PEAKALL

341

The spatial relation of soil erosion and soil types in Jinan based on RS and GIS  

Microsoft Academic Search

The city of Jinan is the capital of Shandong province. The southern mountain of Jinan is a sensitive region of soil erosion. Severe soil erosion not only destroys the ecosystem environment roughly, affects the economic and social sustainable development, but also endangers its spring. Therefore, the assessment of soil erosion, as the basis of the comprehensive control and use planning

Guoping Wu; Huichao Si; Buqing Zhong; Qinshu Wu; Bo Wei; Chonghui Song

2007-01-01

342

Nozzle erosion characterization and minimization for high-pressure rocket motor applications  

Microsoft Academic Search

Understanding of the processes that cause nozzle throat erosion and developing methods for mitigation of erosion rate can allow higher operating pressures for advanced rocket motors. However, erosion of the nozzle throat region, which is a strong function of operating pressure, must be controlled to realize the performance gains of higher operating pressures. The objective of this work was the

Brian Evans

2010-01-01

343

Riebe et al., p. 1 Appendix 1. Cosmogenic Nuclide Methods and Erosion Rate Data  

E-print Network

Riebe et al., p. 1 Appendix 1. Cosmogenic Nuclide Methods and Erosion Rate Data (Supplemental information for "Minimal climatic control on erosion rates in the Sierra Nevada, California") Clifford S-catchment erosion rates, (2) the cosmogenic nuclide production rates that we used, (3) our cosmogenic nuclide

Kirchner, James W.

344

Numerical modeling of erosion using an improvement of the extended finite element  

E-print Network

Numerical modeling of erosion using an improvement of the extended finite element method Régis.diez@upc.edu ABSTRACT. We present in this paper a numerical model of the erosion of a soil that accounts for both fluid and the soil is represented using a level-set function, and the erosion is controlled by the shear

Paris-Sud XI, Université de

345

Soil Erosion: Advanced Crop and Soil Science. A Course of Study.  

ERIC Educational Resources Information Center

The course of study represents the last of six modules in advanced crop and soil science and introduces the agriculture student to the topic of soil erosion. Upon completion of the two day lesson, the student will be able to: (1) define conservation, (2) understand how erosion takes place, and (3) list ways of controlling wind and water erosion.…

Miller, Larry E.

346

Soil erosion and agricultural sustainability  

PubMed Central

Data drawn from a global compilation of studies quantitatively confirm the long-articulated contention that erosion rates from conventionally plowed agricultural fields average 1–2 orders of magnitude greater than rates of soil production, erosion under native vegetation, and long-term geological erosion. The general equivalence of the latter indicates that, considered globally, hillslope soil production and erosion evolve to balance geologic and climate forcing, whereas conventional plow-based agriculture increases erosion rates enough to prove unsustainable. In contrast to how net soil erosion rates in conventionally plowed fields (?1 mm/yr) can erode through a typical hillslope soil profile over time scales comparable to the longevity of major civilizations, no-till agriculture produces erosion rates much closer to soil production rates and therefore could provide a foundation for sustainable agriculture. PMID:17686990

Montgomery, David R.

2007-01-01

347

Seismicity, seismology and erosion  

NASA Astrophysics Data System (ADS)

At the interface of geomorphology and seismology, patterns of erosion can be used to constrain seismic processes, and seismological instruments to determine geomorphic activity. For example, earthquakes trigger mass wasting in proportion to peak ground velocity or acceleration, modulated by local geologic and topographic conditions. This geomorphic response determines the mass balance and net topographic effect of earthquakes. It can also be used to obtain information about the distribution of seismic slip where instrumental observations are not available. Equally, seismometers can register the signals of geomorphic processes, revealing their location, type and magnitude. The high temporal resolution of such records can help determine the exact meteorological conditions that gave rise to erosion events, and the interactions between individual surface processes during such events. We will illustrate this synergy of disciplines with examples from active mountain belts around the world, including Taiwan, Japan, Papua New Guinea and the Alps.

Hovius, Niels; Meunier, Patrick; Burtin, Arnaud; Marc, Odin

2013-04-01

348

Accelerated subduction erosion opposite the Cocos Ridge: Implications for the initiation of ridge subduction  

NASA Astrophysics Data System (ADS)

Subduction erosion has been invoked as the dominant process controlling the tectonic evolution of the Pacific margin of Costa Rica. In an erosive subduction margin, the upper plate material is incorporated into the subduction channel due to basal erosion, resulting in long term subsidence of the upper plate. Estimation of mass removal from the upper plate based on subsidence profiles of slope sediments is crucial to assessing the thickness of the subduction channel. CRISP (Costa Rica Seismogenesis Project) is designed to understand the processes that control fault zone behavior during earthquake nucleation and rupture propagation at erosional subduction zones. IODP Expedition 334 successfully recovered slope sediments offshore the Osa Peninsula where the Cocos Ridge is subducting beneath the Caribbean plate. Preliminary results from biostratigraphic dating obtained from two slope sites indicate high sediment accumulation rates in the terrestrially-sourced slope sequence, ranging from 516-236 m/my at Site U1378 in the middle slope to 1035-160 m/my at Site U1379 in the upper slope. In particular, the accumulation rate of the slope sediments, mainly composed of clayey silt/silty clay, at Site U1379 is 1035 m/my, much higher than that of slope sediments offshore Nicoya (38-99 m/my) (Kimura et al., 1997). The remarkably high accumulation rate offshore Osa could be derived from subaerial uplift triggered by the subduction of the Cocos Ridge. Concomitant with uplift, the subduction of such a bathymetric high likely accelerates the basal erosion of the upper plate. The subsidence/uplift profiles of the slope sediments offshore Osa are controlled by the high sediment accumulation rate and the basal erosion; the subsidence of the upper plate likely occurred when the rate of subduction erosion was exceeded the sediment accumulation rate on the slope. Detailed studies of sedimentary facies and benthic foraminifera faunal in slope sediments at Sites U1378 and U1379 are keys to estimate the mass removal associated with basal erosion and the thickness of the subduction channel that may elucidate earthquake processes. Kimura, G., Silver, E., et al., 1997, Proceedings of the Ocean Drilling Program Initial reports, Volume 170: College Station, Texas, Ocean Drilling Program, 458 p.

Sak, P. B.; Vannucchi, P.; Ohkushi, K.; Ujiie, K.; IODP 334 Scientific Party

2011-12-01

349

33 CFR 263.23 - Small flood control project authority (Section 205).  

...enhancement shall be in accordance with EM 1120-2-109. (e) Limitation on erosion protection. This authority shall not be used for protecting against bank erosion. However, bank stabilization may be included as an integral part of a...

2014-07-01

350

Automatic Control System of Water Conservancy Project Model Based on Multi Agent  

Microsoft Academic Search

In order to improve the precision of model test of the water conservancy project, accelerate the speed of experiment, through bringing in the theory of Multi-Agent, this paper has proposed a kind of new-type Automatic Control System of Water Project Model based on Multi-Agent. This automatic System is made up of Monitoring Agent Federation, namely System control Agent, Flow control

Junhu Yang; Lizhi Yang; Tinghong Zhao; Zhiqiang Jia

2009-01-01

351

PROJECT PLUTO CONTROL SYSTEM DEVELOPMENTS AND TEST RESULTS  

Microsoft Academic Search

Tory Il-A, the first experimental reactor in the Pluto nuclear ramjet ; missile program, was successfully tested. The methods of control which are ; employed on Tory II-A are summarized and unclassified test results pertaining to ; the major control systems are presented. Recent control system developments for ; Tory II-C, a flight-type ramjet reactor, are also described. The Tory

R. E. Finnigan; G. G. Nelson

1961-01-01

352

A Study of Cavitation Erosion  

SciTech Connect

The authors performed experimental study for the purpose of the following two items from a viewpoint of cavitation erosion of a cylindrical orifice in view of a problem at the letdown orifice in PWR (Pressurized Water Reactor). 1. To get the critical cavitation parameter of the cylindrical orifice to establish the design criteria for prevention of cavitation erosion, and 2. to ascertain the erosion rate in such an eventuality that the cavitation erosion occurs with the orifice made of stainless steel with precipitation hardening (17-4-Cu hardening type stainless steel), so that we confirm the appropriateness of the design criteria. Regarding the 1. item, we carried out the cavitation tests to get the critical cavitation parameters inside and downstream of the orifice. The test results showed that the cavitation parameter at inception is independent of the length or the diameter of the orifice. Moreover, the design criteria of cavitation erosion of cylindrical orifices have been established. Regarding the 2. item, we tested the erosion rate under high-pressure conditions. The cavitation erosion actually occurred in the cylindrical orifice at the tests that was strongly resemble to the erosion occurred at the plant. It will be seldom to reproduce resemble cavitation erosion in a cylindrical orifice with the hard material used at plants. We could establish the criteria for preventing the cavitation erosion from the test results. (authors)

Hiromu Isaka [Kansai Electric Power Company (Japan); Masatsugu Tsutsumi; Tadashi Shiraishi [Mitsubishi Heavy Industries Ltd. (Japan); Hiroyuki Kobayashi [Japan Atomic Power Company (Japan)

2002-07-01

353

Estimation of regional differences in wind erosion sensitivity in Hungary  

NASA Astrophysics Data System (ADS)

In Hungary, wind erosion is one of the most serious natural hazards. Spatial and temporal variation in the factors that determine the location and intensity of wind erosion damage are not well known, nor are the regional and local sensitivities to erosion. Because of methodological challenges, no multi-factor, regional wind erosion sensitivity map is available for Hungary. The aim of this study was to develop a method to estimate the regional differences in wind erosion sensitivity and exposure in Hungary. Wind erosion sensitivity was modelled using the key factors of soil sensitivity, vegetation cover and wind erodibility as proxies. These factors were first estimated separately by factor sensitivity maps and later combined by fuzzy logic into a regional-scale wind erosion sensitivity map. Large areas were evaluated by using publicly available data sets of remotely sensed vegetation information, soil maps and meteorological data on wind speed. The resulting estimates were verified by field studies and examining the economic losses from wind erosion as compensated by the state insurance company. The spatial resolution of the resulting sensitivity map is suitable for regional applications, as identifying sensitive areas is the foundation for diverse land development control measures and implementing management activities.

Mez?si, G.; Blanka, V.; Bata, T.; Kovács, F.; Meyer, B.

2015-01-01

354

Critical issues in process control system security : DHS spares project.  

SciTech Connect

The goals of this event are: (1) Discuss the next-generation issues and emerging risks in cyber security for control systems; (2) Review and discuss common control system architectures; (3) Discuss the role of policy, standards, and supply chain issues; (4) Interact to determine the most pertinent risks and most critical areas of the architecture; and (5) Merge feedback from Control System Managers, Engineers, IT, and Auditors.

Hernandez, Jacquelynne; McIntyre, Annie; Henrie, Morgan

2010-10-01

355

Skills Conversion Project, Chapter 8, Pollution Control. Final Report.  

ERIC Educational Resources Information Center

The Skills Conversion Project conducted by the National Society of Professional Engineers sought to study the transition mechanisms required to transfer available technical manpower from aerospace and defense industries into other areas of employment in private industry and public service. Fourteen study teams assessed the likelihood of future…

National Society of Professional Engineers, Washington, DC.

356

Towards Greater Learner Control: Web Supported Project-Based Learning  

ERIC Educational Resources Information Center

Project-based learning has been suggested as an appropriate pedagogy to prepare students in information systems for the realities of the business world. Web-based resources have been used to support such pedagogy with mixed results. The paper argues that the design of web-based learning support to cater to different learning styles may give…

Guthrie, Cameron

2010-01-01

357

PRELIMINARY IMPLEMENTATIONS FOR THE NEW SPIRAL2 PROJECT CONTROL SYSTEM  

Microsoft Academic Search

The Spiral2 project consists of a new facility to provide high intensity rare ions beams. It is based on a primary beam driver accelerator (RFQ followed by a superconducting linac) and a rare ion production process delivering the beam either to a low energy experimental area or to the existing Ganil facility. From October this year, one ion source coupled

P. Gillette; C. Haquin; E. Lécorché; D. Touchard; J. F. Denis; F. Gougnaud; J. F. Gournay; Y. Lussignol; P. Mattei; J. Hosselet; C. Maazouzi; C. Olivetto

358

Piping flow erosion in water retaining structures: inferring erosion rates from hole erosion tests and quantifying the failure time  

E-print Network

Piping flow erosion in water retaining structures: inferring erosion rates from hole erosion tests-en-Provence Cedex 5, France E-mail: stephane.bonelli@cemagref.fr Abstract The piping flow erosion process, involving structures. Such a pipe can be imputed to roots or burrows. The coefficient of erosion must be known in order

Paris-Sud XI, Université de

359

Plasma erosion opening switch  

NASA Astrophysics Data System (ADS)

The plasma erosion opening switch (PEOS) can conduct high current (approx. MA), open quickly ( 10 ns), and withstand high voltage (approx. MV). This switching technique has been used in inductive energy storage experiments and can be used with existing generators for pulse compression, voltage multiplication and power multiplication. The PEOS is used routinely for other types of power conditioning including prepulse suppression, pulse sharpening and multimodule jitter reduction. The PEOS work to data is reviewed. It reviews basic physics principles of the PEOS and outlines the operational limits of a system that employs a PEOS. Examples of present applications of the PEOS are also discussed.

Commisso, R. J.; Cooperstein, G.; Meger, R. A.; Neri, J. M.; Ottinger, P. F.; Weber, B. V.

1985-05-01

360

South Polar Erosion  

NASA Technical Reports Server (NTRS)

24 June 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the results of erosion acting upon a layer of material in the south polar region of Mars. The elliptical pit in the lower left corner of the image was once buried beneath this eroding layer, as well. The processes that eroded the material, and the composition of the material, are unknown. The image is located near 80.7oS, 300.9oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates this scene from the top.

2004-01-01

361

Wind Erosion in Aeolis  

NASA Technical Reports Server (NTRS)

09 August 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the effects of severe wind erosion of layered sedimentary rock in the Aeolis region of Mars. The sharp ridges formed by wind movement from the lower left (southwest) toward top/upper right (northeast) are known as yardangs. The dark patches in the lower half of the image are sand dunes. This scene is located near 5.0oS, 203.7oW, and covers an area about 3 km (1.9 mi) across. Sunlight illuminates the terrain from the left/upper left.

2004-01-01

362

The Monitoring Erosion of Agricultural Land and spatial database of erosion events  

NASA Astrophysics Data System (ADS)

In 2011 originated in The Czech Republic The Monitoring Erosion of Agricultural Land as joint project of State Land Office (SLO) and Research Institute for Soil and Water Conservation (RISWC). The aim of the project is collecting and record keeping information about erosion events on agricultural land and their evaluation. The main idea is a creation of a spatial database that will be source of data and information for evaluation and modeling erosion process, for proposal of preventive measures and measures to reduce negative impacts of erosion events. A subject of monitoring is the manifestations of water erosion, wind erosion and slope deformation in which cause damaged agriculture land. A website, available on http://me.vumop.cz, is used as a tool for keeping and browsing information about monitored events. SLO employees carry out record keeping. RISWC is specialist institute in the Monitoring Erosion of Agricultural Land that performs keeping the spatial database, running the website, managing the record keeping of events, analysis the cause of origins events and statistical evaluations of keeping events and proposed measures. Records are inserted into the database using the user interface of the website which has map server as a component. Website is based on database technology PostgreSQL with superstructure PostGIS and MapServer UMN. Each record is in the database spatial localized by a drawing and it contains description information about character of event (data, situation description etc.) then there are recorded information about land cover and about grown crops. A part of database is photodocumentation which is taken in field reconnaissance which is performed within two days after notify of event. Another part of database are information about precipitations from accessible precipitation gauges. Website allows to do simple spatial analysis as are area calculation, slope calculation, percentage representation of GAEC etc.. Database structure was designed on the base of needs analysis inputs to mathematical models. Mathematical models are used for detailed analysis of chosen erosion events which include soil analysis. Till the end 2012 has had the database 135 events. The content of database still accrues and gives rise to the extensive source of data that is usable for testing mathematical models.

Kapicka, Jiri; Zizala, Daniel

2013-04-01

363

Soil erosion, policy and management in China coastal zone  

NASA Astrophysics Data System (ADS)

The coastal zone is very important in the world. China coastal zone was granted the first priority of developing economy in the late 1980s. Since then, high population density and rapid economic development hace caused intensive changes of LUCC in this zone. Those changes have lead to land degradation. Besides, China governments launched series of projects and policy to improve such problems. Those will inevitably cause to diverse spatial dynamics of land degradtion. However, the state of land degradation in certain time is still unknown. Soil erosion is an important indicator of land degradation.Therefore, we use RS images?RUSLE model to anlyze the spatial pattern of soil erosion for 2000. By spatial analysis, we found that soil erosion in China coastal zone is not serious. Widespread soil erosion is only occurred on coastal zones in Shandong, Hainan and werstern Guangdong Province. Although rainfall eosivity factor(R) is higher in southern coastal zone, erosion tends to occur on the slopes with lower LS values in northern coastal zone than southern coastal zone. Goevernments have enforced some policy to reduce the extent of soil erosion by conversion of farmland to woodland and barren mountains to woodland. But the difference between southern and northern coastal zone is still not realized. To improve soil eorosion in those areas, we should let governments put more funds to increase vegetation cover in north. Such study will provide helpful suggestions for governments to prevent soil erosion in coastal zone.

Lu, Qingshui; Gao, Zhiqiang; Chen, Qiao; Ning, Jicai; Shi, Runhe; Gao, Wei

2013-09-01

364

Noise prediction and control of Pudong International Airport expansion project  

Microsoft Academic Search

The Environmental Impact Assessment (EIA) process of the third runway building project of Pudong International Airport is\\u000a briefly introduced in the paper. The basic principle, the features, and the operation steps of newly imported FAA’s Integrated\\u000a Noise Model (INM) are discussed for evaluating the aircraft noise impacts. The prediction of the aircraft noise and the countermeasures\\u000a for the noise mitigation

Bin Lei; Xin Yang; Jianguo Yang

2009-01-01

365

An application of mathematical models to select the optimal alternative for an integral plan to desertification and erosion control (Chaco Area - Salta Province - Argentina)  

NASA Astrophysics Data System (ADS)

Multi-criteria Decision Analysis (MCDA) is concerned with identifying the values, uncertainties and other issues relevant in a given decision, its rationality, and the resulting optimal decision. These decisions are difficult because the complexity of the system or because of determining the optimal situation or behaviour. This work will illustrate how MCDA is applied in practice to a complex problem to resolve such us soil erosion and degradation. Desertification is a global problem and recently it has been studied in several forums as ONU that literally says: "Desertification has a very high incidence in the environmental and food security, socioeconomic stability and world sustained development". Desertification is the soil quality loss and one of FAO's most important preoccupations as hunger in the world is increasing. Multiple factors are involved of diverse nature related to: natural phenomena (water and wind erosion), human activities linked to soil and water management, and others not related to the former. In the whole world this problem exists, but its effects and solutions are different. It is necessary to take into account economical, environmental, cultural and sociological criteria. A multi-criteria model to select among different alternatives to prepare an integral plan to ameliorate or/and solve this problem in each area has been elaborated taking in account eight criteria and five alternatives. Six sub zones have been established following previous studies and in each one the initial matrix and weights have been defined to apply on different criteria. Three multicriteria decision methods have been used for the different sub zones: ELECTRE, PROMETHEE and AHP. The results show a high level of consistency among the three different multicriteria methods despite the complexity of the system studied. The methods are fully described for La Estrella sub zone, indicating election of weights, Initial Matrixes, algorithms used for PROMETHEE, and the Graph of Expert Choice showing the AHP results. A brief schema of the actions recommended for each of the six different sub zones is discussed.

Grau, J. B.; Antón, J. M.; Tarquis, A. M.; Colombo, F.; de Los Ríos, L.; Cisneros, J. M.

2010-11-01

366

Assessment of the use of sediment fences for control of erosion and sediment phosphorus loss after potato harvesting on sloping land.  

PubMed

In humid temperate areas, after harvest of potatoes, it is difficult to prevent soil erosion and diffuse pollution. In some autumn weather conditions, in-field mitigation such as cultivation or sowing are not possible, while edge of field measures can be costly and inflexible. We have assessed the potential of modified sediment fences, widely used on building sites, for erosion mitigation post-harvest of potato crops. Field scale assessments were conducted on fields in the Lunan catchment, eastern Scotland. Sediment retention was estimated by two methods: a topographic survey method using a hand held Real Time Kinematic Global Positioning System (RTK-GPS), and direct measurement of sediment depth using a graduated cane. In the 2010/11 trial the main fence comprised 70 m of entrenched fine mesh (0.25 mm) and coarser mesh (4mm) fabric pinned to a contour fence near the base of the field. This retained an estimated 50.9 m(3) (80.2 tonnes) of sediment, with weighted mean total P (TP) content of 0.09 % in the<2mm soil fraction. In the 2011/12 trial, the main 146 m fence was of intermediate mesh size (1.2mm). The fence was partitioned into nine upslope plots, with 3 replicates of each of 3 cultivation methods: T1 (full grubbing--a light, tined cultivator), T2 (partial grubbing) and T3 (no grubbing). Average plot slopes ranged from 9.9 to 11.0 %. The amounts of TP accumulating as sediment at the fences were: 9.3 (sd = 7.8), 11.8 (sd = 10.2) and 25.7 (sd = 5.8)kg P/ha of upslope plot for the T1, T2 and T3 treatments respectively. PMID:24012897

Vinten, A J A; Loades, K; Addy, S; Richards, S; Stutter, M; Cook, Y; Watson, H; Taylor, C; Abel, C; Baggaley, N; Ritchie, R; Jeffrey, W

2014-01-15

367

Reprint of: Assessment of the use of sediment fences for control of erosion and sediment phosphorus loss after potato harvesting on sloping land.  

PubMed

In humid temperate areas, after harvest of potatoes, it is difficult to prevent soil erosion and diffuse pollution. In some autumn weather conditions, in-field mitigation such as cultivation or sowing are not possible, while edge of field measures can be costly and inflexible. We have assessed the potential of modified sediment fences, widely used on building sites, for erosion mitigation post-harvest of potato crops. Field scale assessments were conducted on fields in the Lunan catchment, eastern Scotland. Sediment retention was estimated by two methods: a topographic survey method using a hand held Real Time Kinematic Global Positioning System (RTK-GPS), and direct measurement of sediment depth using a graduated cane. In the 2010/11 trial the main fence comprised 70 m of entrenched fine mesh (0.25 mm) and coarser mesh (4mm) fabric pinned to a contour fence near the base of the field. This retained an estimated 50.9 m(3) (80.2 tonnes) of sediment, with weighted mean total P (TP) content of 0.09 % in the<2mm soil fraction. In the 2011/12 trial, the main 146 m fence was of intermediate mesh size (1.2mm). The fence was partitioned into nine upslope plots, with 3 replicates of each of 3 cultivation methods: T1 (full grubbing--a light, tined cultivator), T2 (partial grubbing) and T3 (no grubbing). Average plot slopes ranged from 9.9 to 11.0 %. The amounts of TP accumulating as sediment at the fences were: 9.3 (sd=7.8), 11.8 (sd=10.2) and 25.7 (sd=5.8)kg P/ha of upslope plot for the T1, T2 and T3 treatments respectively. PMID:24200093

Vinten, A J A; Loades, K; Addy, S; Richards, S; Stutter, M; Cook, Y; Watson, H; Taylor, C; Abel, C; Baggaley, N; Ritchie, R; Jeffrey, W

2014-01-15

368

Integrated Resilient Aircraft Control Project Full Scale Flight Validation  

NASA Technical Reports Server (NTRS)

Objective: Provide validation of adaptive control law concepts through full scale flight evaluation. Technical Approach: a) Engage failure mode - destabilizing or frozen surface. b) Perform formation flight and air-to-air tracking tasks. Evaluate adaptive algorithm: a) Stability metrics. b) Model following metrics. Full scale flight testing provides an ability to validate different adaptive flight control approaches. Full scale flight testing adds credence to NASA's research efforts. A sustained research effort is required to remove the road blocks and provide adaptive control as a viable design solution for increased aircraft resilience.

Bosworth, John T.

2009-01-01

369

9 CFR 79.7 - Waiver of requirements for scrapie control pilot projects.  

Code of Federal Regulations, 2011 CFR

...SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS SCRAPIE IN SHEEP AND GOATS § 79.7 Waiver of requirements for scrapie control pilot projects. (a) The Administrator may waive...

2011-01-01

370

9 CFR 79.7 - Waiver of requirements for scrapie control pilot projects.  

Code of Federal Regulations, 2013 CFR

...SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS SCRAPIE IN SHEEP AND GOATS § 79.7 Waiver of requirements for scrapie control pilot projects. (a) The Administrator may waive...

2013-01-01

371

9 CFR 79.7 - Waiver of requirements for scrapie control pilot projects.  

Code of Federal Regulations, 2012 CFR

...SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS SCRAPIE IN SHEEP AND GOATS § 79.7 Waiver of requirements for scrapie control pilot projects. (a) The Administrator may waive...

2012-01-01

372

9 CFR 79.7 - Waiver of requirements for scrapie control pilot projects.  

...SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS SCRAPIE IN SHEEP AND GOATS § 79.7 Waiver of requirements for scrapie control pilot projects. (a) The Administrator may waive...

2014-01-01

373

75 FR 28626 - Disease, Disability, and Injury Prevention and Control Special Interest Projects (SIPs): SIP 10...  

Federal Register 2010, 2011, 2012, 2013

...Prevention and Control Special Interest Projects (SIPs): SIP 10-029, Pilot Study--Cancer Survivorship Care Planning & SIP 10-030, Evaluating Special...Study--Cancer Survivorship Care Planning & SIP 10- 030, Evaluating...

2010-05-21

374

SPECIAL PROJECTS (AIR POLLUTION TECHNOLOGY BRANCH, AIR POLLUTION PREVENTION AND CONTROL DIVISION, NRMRL)  

EPA Science Inventory

Special projects undertaken by the Air Pollution Technology Branch of NRMRL's Air Pollution Prevention and Control Division in Research Triangle Park, NC, include the Orimulsion Research Study, Real-Time Monitoring of Dioxins and Other Trace Organics, and Environmental Technology...

375

Optimal timing control in game modeling of an energy project infrastructure  

Microsoft Academic Search

The purpose of this paper is to study an optimal infrastructure of a system of international gas pipelines competing for a gas market. We suggest a game-dynamic model of the operation of several interacting gas pipeline projects treated as players in the game. The model treats the projects’ commercialization times as major players’ controls. Current quantities of gas supply are

Andrey A. Krasovskii; Ivan V. Matrosov; Alexander M. Tarasyev

2009-01-01

376

Design Project on Controlled-Release Drug Delivery Devices: Implementation, Management, and Learning Experiences  

ERIC Educational Resources Information Center

A design project that focuses on the subject of controlled-release drug delivery devices is presented for use in an undergraduate course on mass transfer. The purpose of the project is to introduce students to the various technologies used in the fabrication of drug delivery systems and provide a practical design exercise for understanding the…

Xu, Qingxing; Liang, Youyun; Tong, Yen Wah; Wang, Chi-Hwa

2010-01-01

377

RIPARIAN AND RELATED VALUES ASSOCIATED WITH FLOOD CONTROL PROJECT ALTERNATIVES AT WILDCAT AND SAN  

E-print Network

RIPARIAN AND RELATED VALUES ASSOCIATED WITH FLOOD CONTROL PROJECT ALTERNATIVES AT WILDCAT AND SAN PABLO CREEKS1 Philip A. Meyer 2 1 Presented at the California Riparian Systems Conference; September 22 will consider Riparian benefits from alternative project designs at Wildcat and San Pablo Creeks. Particular

Standiford, Richard B.

378

Dependable Dataflow Control Systems SPONSORS OF THE PROJECT  

E-print Network

of control systems by means of a dataflow design description language. It allows to specify fuctional as well. Simoncini, "Data-Flow like Languages for Real-Time Systems: Issues of Computational Models and Notation

Firenze, Università degli Studi di

379

Control Systems for Information Systems Development Projects (Part I)  

ERIC Educational Resources Information Center

Discusses control of management information systems and finds a similarity in management of research and development activity. Part II will appear in AEDS Journal, Volume 4, number 2, December 1970. (JF)

Dickson, Gary W.

1970-01-01

380

Formation shape and orientation control using projected collinear tensegrity structures  

Microsoft Academic Search

The goal of this work is to stabilize the shape and orientation of formations of N identical and fully actuated agents, each governed by double-integrator dynamics. Using stability and rigidity properties inherent to tensegrity structures, we first design a tensegrity-based, globally exponentially stable control law in one dimension. This stabilizes given inter-agent spacing along the line, thereby enabling shape control

Darren Pais; Ming Cao; Naomi Ehrich Leonard

2009-01-01

381

Soil erosion and the global carbon budget  

Microsoft Academic Search

Soil erosion is the most widespread form of soil degradation. Land area globally affected by erosion is 1094 million ha (Mha) by water erosion, of which 751 Mha is severely affected, and 549 Mha by wind erosion, of which 296 Mha is severely affected. Whereas the effects of erosion on productivity and non-point source pollution are widely recognized, those on

R. Lal

2003-01-01

382

Distributed soil erosion simulation for effective erosion prevention  

Microsoft Academic Search

We present a bivariate model of erosion, sediment transport, and deposition by overland flow, designed for complex terrain, soil, and cover conditions. We use a Green's function Monte Carlo method to solve the underlying continuity equations, leading to improved robustness and implementation efficiency. By deriving the relationship between the terrain shape and erosion\\/deposition pattern, we clarify the physical interpretation of

Lubos Mitas; Helena Mitasova

1998-01-01

383

Integrated computer control system CORBA-based simulator FY98 LDRD project final summary report  

Microsoft Academic Search

The CORBA-based Simulator was a Laboratory Directed Research and Development (LDRD) project that applied simulation techniques to explore critical questions about distributed control architecture. The simulator project used a three-prong approach comprised of a study of object-oriented distribution tools, computer network modeling, and simulation of key control system scenarios. This summary report highlights the findings of the team and provides

R M Bryant; F W Holloway; P J Van Arsdall

1999-01-01

384

CRCHD SPN Project: SPN Project Description: Greater Denver Latino Cancer Prevention/Control Network  

Cancer.gov

The Latino Research and Policy Center at the University of Colorado at Denver, built a network infrastructure among community-based Latino organizations, health clinics, social service agencies, school-based clinics, faith-based groups, and employee-based organizations serving Latinos in the greater Denver metropolitan area. The network's infrastructure for cancer awareness, education, and pilot research projects was based on existing relationships and ongoing intervention and education activities. Activities were focused on breast, cervical, prostate, colorectal, and lung cancers.

385

Toward integrated opisthorchiasis control in northeast Thailand: The Lawa project.  

PubMed

Human liver fluke, Opisthorchis viverrini, a food-borne trematode is a significant public health problem in Southeast Asia, particularly in Thailand. Despite a long history of control programmes in Thailand and a nationwide reduction, O. viverrini infection prevalence remains high in the northeastern provinces. Therefore, a new strategy for controlling the liver fluke infection using the EcoHealth/One Health approach was introduced into the Lawa Lake area in Khon Kaen province where the liver fluke is endemic. A programme has been carried using anthelminthic treatment, novel intensive health education methods both in the communities and in schools, ecosystem monitoring and active community participation. As a result, the infection rate in the more than 10 villages surrounding the lake has declined to approximate one third of the average of 50% as estimated by a baseline survey. Strikingly, the Cyprinoid fish species in the lake, which are the intermediate host, now showed less than 1% prevalence compared to a maximum of 70% at baseline. This liver fluke control programme, named "Lawa model," is now recognised nationally and internationally, and being expanding to other parts of Thailand and neighbouring Mekong countries. Challenges to O. viverrini disease control, and lessons learned in developing an integrative control programme using a community-based, ecosystem approach, and scaling-up regionally based on Lawa as a model are described. PMID:25102053

Sripa, Banchob; Tangkawattana, Sirikachorn; Laha, Thewarach; Kaewkes, Sasithorn; Mallory, Frank F; Smith, John F; Wilcox, Bruce A

2015-01-01

386

Soil erosion and sediment yield prediction on catchment and regional scale using a process based simulation model  

NASA Astrophysics Data System (ADS)

The prevention of erosion is one of the main issues in the EU-Water Framework Directive (WFD) and the European Agricultural Fund for Rural Development (EAFRD). Planning and dimensioning of soil conservation measures require reliable and detailed information on the temporal and spatial distribution of soil detachment, soil transport and deposition. Soil erosion models are increasingly used, in order to simulate the physical processes involved and to predict the effects of soil erosion control measures. In this study the EROSION 3D simulation model is used for surveying soil erosion and deposition on the catchment scale covering the entire state of Saxony/Germany (18.500 km²). EROSION 3D is a distributed, extensively validated GIS based soil loss and deposition model including sediment delivery to surface water bodies. However, the application of the model for an entire state is a new challenge, because of the enormous data requirements and complex data processing operations prior to simulation. In this context the study includes the compilation, validation and generalisation of existing land use and soil data in order to generate a consistent EROSION 3D input dataset for the entire state of Saxony. As a part of this process the interface software DPROC allows to transfer the original soil and land use data into model specific data. The project aims to extend the interface software DPROC by an interactive GIS-component which enables the user to select arbitrary hydrological watersheds including the related soil and land use data. Based on these data DPROC automatically creates the according EROSION 3D input files using a relational database of primary data and model specific data. DPROC uses parameter transfer tables in order to specify the relationship between primary soil and land use data and model specific data. This combined methodology provides different risk assessment maps for certain demands on the regional scale of a Federal State. Besides soil loss and sediment transport sediment pass over points into surface water bodies and particle enrichment can be simulated using the EROSION 3D model. Thus the estimation of particle bound nutrient and pollutant inputs into surface water bodies according to the WFD demands is possible. The study ended up in a user-friendly, timesaving and improved software package for the simulation of soil loss and deposition on a regional scale providing essential information for the planning of soil and water conservation measures particularly under consideration of expected land use and climate changes.

Schindewolf, Marcus; Schmidt, Jürgen

2010-05-01

387

Organization features of the work control quality improvement project  

SciTech Connect

One consequence of {open_quotes}reengineering{close_quotes} - the systematic review, design, and implementation of process, technology, and organization - is improvement in process efficiency. This improvement also causes change in organization size and function. This paper describes some of the key changes to organizational function brought about by Duke Power Company`s reengineering of the work control process. The fundamental principle observed during the Duke nuclear stations` recent organizational realignment is focus on the process. The process of work control must satisfy the customer needs of the station equipment owners. The changes to the organization serve to fulfill the numerous process requirements.

Dulin, R.

1994-12-31

388

Does vegetation prevent wave erosion of salt marsh edges?  

PubMed Central

This study challenges the paradigm that salt marsh plants prevent lateral wave-induced erosion along wetland edges by binding soil with live roots and clarifies the role of vegetation in protecting the coast. In both laboratory flume studies and controlled field experiments, we show that common salt marsh plants do not significantly mitigate the total amount of erosion along a wetland edge. We found that the soil type is the primary variable that influences the lateral erosion rate and although plants do not directly reduce wetland edge erosion, they may do so indirectly via modification of soil parameters. We conclude that coastal vegetation is best-suited to modify and control sedimentary dynamics in response to gradual phenomena like sea-level rise or tidal forces, but is less well-suited to resist punctuated disturbances at the seaward margin of salt marshes, specifically breaking waves. PMID:19509340

Feagin, R. A.; Lozada-Bernard, S. M.; Ravens, T. M.; Möller, I.; Yeager, K. M.; Baird, A. H.

2009-01-01

389

Coastal Change Along the Shore of Northeastern South Carolina: The South Carolina Coastal Erosion Study  

USGS Publications Warehouse

The U.S. Geological Survey, in cooperation with the South Carolina Sea Grant Consortium, conducted a 7-year, multi-disciplinary study of coastal erosion in northeastern South Carolina. The main objective was to understand the geologic and oceanographic processes that control sediment movement along the region's shoreline and thereby improve projections of coastal change. The study used high-resolution remote sensing and sampling techniques to define the geologic framework and assess historic shoreline change. Based on these findings, oceanographic-process studies and numerical modeling were carried out to determine the rates and directions of sediment transport along South Carolina's Grand Strand.

Barnhardt, W. A., (Edited By)

2009-01-01

390

Is splash erosion potential species specific? Measuring of splash erosion potential under forest in different succession stages along a biodiversity gradient in the humid subtropics  

NASA Astrophysics Data System (ADS)

It is widely accepted that (forest) vegetation is a key control for the type and intensity of soil erosion. The current paradigm is that natural or quasi-natural vegetation protects the soil from erosion and that agricultural vegetation or land use generally enhances erosion. The latter was in focus of most research during the last decades and less interest was paid on natural systems, which are more difficult to study. Nevertheless, afforestation is widely used as a measure of soil protection against soil erosion. Rainfall can be highly erosive particularly in the humid subtropics. Regarding climate change, also precipitation regime may change in direction to even more severe storms and higher rainfall intensities; it is a research field of growing importance. Key mechanisms of a vegetation cover in reducing or enhancing erosion are modifications of drop-size distribution, retention of raindrop impact on the soil and changes in amount and spatial distribution of rainfall at the ground surface. Controlling determinants are rainfall intensity, drop size distribution, drop fall velocity, height of the canopy as well as density of the canopy, crown and leaf traits, LAI and coverage by a litter layer. Large drops are supposed to be significant sources of splash detachment in forests (Brandt 1989; Vis 1986). However, the mechanisms of reducing (or enhancing?) splash detachment under forest in relation to species richness and species composition are not well understood. Some studies indicate that raindrop impact is species specific (Calder 2001; Nanko et al. 2006) and some neglect the effects of species specific impacts (Foot & Morgan 2005). Our research uses different methods of rainfall characterization (splash cups, tipping-bucket rain gauge, laser distrometer) to reveal the described mechanisms from the canopy through different vegetation layers to the ground. First results of splash cup measurements (revised after Ellison 1947) show that sand loss under vegetation is 2.5 times higher than in open field despite the fact that only 60 percent of open field rainfall reaches the ground. The results also indicate that sand loss is a function of the age of the specific forest stand and the variability of sand loss under different species with respect to space and time. These and future results will help managing afforestation projects in giving implications which of the species (resp. species compositions) may reduce most effectively potential splash erosion. References: Brandt, C. J. (1989): The size distribution of throughfall drops under vegetation canopies. Catena 16, p. 507-524. Calder, I. R. (2001): Canopy processes: implications for transpiration, interception and splash induced erosion, ultimately for forest management and water resources. Plant Ecology 153, p. 203-214. Ellison, W. D. (1947): Soil Erosion Studies - Part II. Soil Detachment Hazard by Raindrop Splash. Agricultural Engineering 28, p. 197-201. Foot, K.; Morgan, R. P. C. (2005): The role of leaf inclination, leaf orientation and plant canopy architecture in soil particle detachment by raindrops. Earth Surface Processes and Landforms 30, p. 1509-1520. Nanko, K.; Hotta, N. & Suzuki, M. (2006): Evaluating the influence of canopy species and meteorological factors on throughfall drop size distribution. Journal of Hydrology 329, p. 422-431. Vis, M. (1986): Interception, drop size distributions and rainfall kinetic energy in four colombian forest ecosystems. Earth Surface Processes and Landforms 11, p. 591-603.

Geißler, C.; Kühn, P.; Scholten, T.

2009-04-01

391

Contributions of EU-project REPCO to apple scab control  

Microsoft Academic Search

The objective of REPCO is to contribute to the replacement of copper fungicides in organic agriculture by new measures for control of downy mildew (Plasmopara viticola) in grapevine and scab (Venturia inaequalis) in apple. Both major European organic crops strongly depend on copper fungicides. Permitted amounts will be reduced stepwise during the following years (Council Regulation (EEC) 2092\\/91, Annex II)

J. Köhl; B. Heijne; J. Hockenhull; H. Lindhard Pedersen; M. Trapman; U. Eiben; L. Tamm

2006-01-01

392

WIND EROSION AND WATER RESOURCES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wind erosion is the movement and loss of soil resulting from the interaction of a bare, loose, dry soil surface with wind. Although wind erosion occurs on all continents and in all climates it is most prevalent and its effects are most profound in arid and semi arid areas of the northern hemisphere...

393

THROUGHFLOW, OVERLAND FLOW AND EROSION  

Microsoft Academic Search

The Horton (1945) infiltration model of surface runoff and erosion is shown to be of much more limited geomorphic application than has been recognised hitherto. It is most applicable to clay badlands with low infiltration capacities and little weathered cover, and is one end-member of a wide spectrum of erosion models. The other end-member applies to slopes with high infiltration

M. J. KIRKBY; R. J. CHORLEY

1967-01-01

394

Hydraulic wellbore erosion while drilling  

Microsoft Academic Search

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

B. Chemerinski; L. Robinson

1996-01-01

395

WIND-DRIVEN RAINSPLASH EROSION  

Technology Transfer Automated Retrieval System (TEKTRAN)

The erosion process involves detachment of soil particles from a soil surface and transport of these particles from their first location. The main agents that loosen, break down, and carry the soil particles are wind and water. Wind and water erosion processes have traditionally been separately stu...

396

SOIL EROSION AND CONSERVATION: PREDICTION  

E-print Network

COVER CROP RESIDUE COVER CROPS INCREASE STUBBLE HEIGHT INSTALL WINDBREAKS EFFECTIVE 15x HEIGHT-MADISON Presented 12 Feb 2003 in Dr. Stoltenberg's Cropping Systems Class #12;SOIL EROSION IS GLOBAL PROBLEM 1SOIL EROSION AND CONSERVATION: PREDICTION AND MANAGEMENT DICK WOLKOWSKI DEPT. OF SOIL SCIENCE UW

Balser, Teri C.

397

Mathematical model to select the optimal alternative for an integral plan to desertification and erosion control for the Chaco Area in Salta Province (Argentine)  

NASA Astrophysics Data System (ADS)

Multi-criteria Decision Analysis (MCDA) is concerned with identifying the values, uncertainties and other issues relevant in a given decision, its rationality, and the resulting optimal decision. These decisions are difficult because the complexity of the system or because of determining the optimal situation or behavior. This work will illustrate how MCDA is applied in practice to a complex problem to resolve such us soil erosion and degradation. Desertification is a global problem and recently it has been studied in several forums as ONU that literally says: "Desertification has a very high incidence in the environmental and food security, socioeconomic stability and world sustained development". Desertification is the soil quality loss and one of FAO's most important preoccupations as hunger in the world is increasing. Multiple factors are involved of diverse nature related to: natural phenomena (water and wind erosion), human activities linked to soil and water management, and others not related to the former. In the whole world this problem exists, but its effects and solutions are different. It is necessary to take into account economical, environmental, cultural and sociological criteria. A multi-criteria model to select among different alternatives to prepare an integral plan to ameliorate or/and solve this problem in each area has been elaborated taking in account eight criteria and six alternatives. Six sub zones have been established following previous studies and in each one the initial matrix and weights have been defined to apply on different criteria. Three Multicriteria Decision Methods have been used for the different sub zones: ELECTRE, PROMETHEE and AHP. The results show a high level of consistency among the three different multicriteria methods despite the complexity of the system studied. The methods are described for La Estrella sub zone, indicating election of weights, Initial Matrixes, the MATHCAD8 algorithms used for PROMETHEE, and the Graph of Expert Choice showing the results of AHP. A brief schema of the actions recommended for each of the six different sub zones is reported in Conclusions, with "We can combine Autochthonous and High Value Forest" for La Estrella.

Grau, J. B.; Anton, J. M.; Tarquis, A. M.; Colombo, F.; de Los Rios, L.; Cisneros, J. M.

2010-04-01

398

CRCHD SPN Project: Special Populations Network for Cancer Control  

Cancer.gov

The Special Populations Network for Cancer Control (SPNCC) targeted its cancer awareness and behavior-change programs within Region 2 of the National Medical Association (the premier professional society for African-American physicians in the United States), which comprises Delaware, the District of Columbia, Maryland, Pennsylvania, Virginia, and West Virginia. The SPNCC Steering Committee presented seminars and workshops throughout Region 2 and guided the Network's research and programmatic agenda.

399

The Adjustment of the Blue Nile Geodetic Control Project  

Microsoft Academic Search

The adjustment of the Ethiopian survey data was performed by methods developed and in current use by the U.S. Coast and Geodetic Survey. The basic level network furnished control for a least-squares solution of reciprocal zenith distance observations, after which a least- squares adjustment of the horizontal directions was made. Laplace azimuths and invar-taped bases were held fixed. Tellurometer lengths

Wallace H. Blackwell

1962-01-01

400

A revealed preference approach to estimating supply curves for ecosystem services: use of auctions to set payments for soil erosion control in Indonesia.  

PubMed

To supply ecosystem services, private landholders incur costs. Knowledge of these costs is critical for the design of conservation-payment programs. Estimating these costs accurately is difficult because the minimum acceptable payment to a potential supplier is private information. We describe how an auction of payment contracts can be designed to elicit this information during the design phase of a conservation-payment program. With an estimate of the ecosystem-service supply curve from a pilot auction, conservation planners can explore the financial, ecological, and socioeconomic consequences of alternative scaled-up programs. We demonstrate the potential of our approach in Indonesia, where soil erosion on coffee farms generates downstream ecological and economic costs. Bid data from a small-scale, uniform-price auction for soil-conservation contracts allowed estimates of the costs of a scaled-up program, the gain from integrating biophysical and economic data to target contracts, and the trade-offs between poverty alleviation and supply of ecosystem services. Our study illustrates an auction-based approach to revealing private information about the costs of supplying ecosystem services. Such information can improve the design of programs devised to protect and enhance ecosystem services. PMID:18983597

Jack, B Kelsey; Leimona, Beria; Ferraro, Paul J

2009-04-01

401

Bank Erosion as a Desirable Attribute of Rivers  

NSDL National Science Digital Library

Bank erosion is integral to the functioning of river ecosystems. It is a geomorphic process that promotes riparian vegetation succession and creates dynamic habitats crucial for aquatic and riparian plants and animals. River managers and policymakers, however, generally regard bank erosion as a process to be halted or minimized in order to create landscape and economic stability. Here, we recognize bank erosion as a desirable attribute of rivers. Recent advances in our understanding of bank erosion processes and of associated ecological functions, as well as of the effects and failure of channel bank infrastructure for erosion control, suggest that alternatives to current management approaches are greatly needed. In this article, we develop a conceptual framework for alternatives that address bank erosion issues. The alternatives conserve riparian linkages at appropriate temporal and spatial scales, consider integral relationships between physical bank processes and ecological functions, and avoid secondary and cumulative effects that lead to the progressive channelization of rivers. By linking geomorphologic processes with ecological functions, we address the significance of channel bank erosion in sustainable river and watershed management.

Joan L. Florsheim (University of California at Davis;)

2008-06-01

402

The United States Department of Agriculture northeast area-wide tick control project - history and protocol  

Technology Transfer Automated Retrieval System (TEKTRAN)

This manuscript summarizes the history of development of the ARS-patented ‘4-Poster’ Deer Treatment Bait Station technology for the control of ticks feeding on white-tailed deer and other wild ungulates, provides the rationale for its use in the USDA Northeast Area-wide Tick Control Project, and des...

403

Controlled landfill project: Mountain View, California. Annual report, January-December 1982  

Microsoft Academic Search

This project studied the effects of leachate recirculation and added water, buffer and sludge on enhancing the generation and improving the recovery of landfill gas. It evaluated the various techniques by providing individual control cells for the demonstration of enhancement methods. The study also documents landfill gas productions from a controlled volume at field scale. Results from this study provide

T. A. Bonham; R. E. Van Heuit; W. M. Carroll; M. Donch

1984-01-01

404

Real-Time, CNC Machine Tool Control with Linux: A Senior Design Project at MUSE  

Microsoft Academic Search

As machine tools age and their existing controllers fail, the machine tools must be either modernized or scrapped. This paper details the infusion of new technology and the resulting extended useful life of a computer numerical controlled (CNC) tabletop lathe. This work was undertaken as a senior design project by a group of senior engineers at Mercer University School of

Tie Duan; Ronnie Baroud; Daniel Amato; Albert LaRoe

405

Master Thesis / Semester Project / Summer Project Cooperative Control of Aerial and Ground Robots  

E-print Network

architecture of the testbed is shown in the figure on the right, with a vision based localization system Description: Multiagent systems are more and more often employed to obtain inherently robust solutions to many to evaluate controllers for autonomous driving of the trucks, and autonomous navigation of quadrotors

Dimarogonas, Dimos

406

National Ignition Facility Project Completion and Control System Status  

SciTech Connect

The National Ignition Facility (NIF) is the world's largest and most energetic laser experimental system providing a scientific center to study inertial confinement fusion (ICF) and matter at extreme energy densities and pressures. Completed in 2009, NIF is a stadium-sized facility containing a 1.8-MJ, 500-TW 192-beam ultraviolet laser and target chamber. A cryogenic tritium target system and suite of optical, X-ray and nuclear diagnostics will support experiments in a strategy to achieve fusion ignition starting in 2010. Automatic control of NIF is performed by the large-scale Integrated Computer Control System (ICCS), which is implemented by 2 MSLOC of Java and Ada running on 1300 front-end processors and servers. The ICCS framework uses CORBA distribution for interoperation between heterogeneous languages and computers. Laser setup is guided by a physics model and shots are coordinated by data-driven distributed workflow engines. The NIF information system includes operational tools and a peta-scale repository for provisioning experimental results. This paper discusses results achieved and the effort now underway to conduct full-scale operations and prepare for ignition.

Van Arsdall, P J; Azevedo, S G; Beeler, R G; Bryant, R M; Carey, R W; Demaret, R D; Fisher, J M; Frazier, T M; Lagin, L J; Ludwigsen, A P; Marshall, C D; Mathisen, D G; Reed, R K

2009-10-02

407

A Manual of Mosquito Control Projects and Committee Assignments for 4-H and Scouts Biology Class Projects, Organized Community Service Programs, and Individuals Interested in Environmental Management.  

ERIC Educational Resources Information Center

The mosquito control projects presented in this manual were prepared from an educational viewpoint and are intended for use by students in 4-H and Scouts and as a supplement to high school and college biology course work. The major emphasis of the projects is on integrated pest management, an approach utilizing cost-effective control methods which…

Hart, Richard A.

408

Comment [on “Sea level rise shown to drive coastal erosion  

USGS Publications Warehouse

In a recent article (Eos, Trans., AGU, February 8, 2000, p.55), Leatherman et al. [2000] state that they have confirmed an association between sea-level rise and coastal erosion. Applying their results to the New Jersey, Delaware, and Maryland coasts and using a projected sea-level rise, the authors predict that by 2050 the shoreline will recede 60 m, about two times the average beach width. However, Leatherman et al. [2000] have not convincingly quantified a relationship between sea-level rise and shoreline erosion.We do not agree with their rationale for subsetting their data, and they have not considered other explanations for a background erosion along the U.S. east coast. Furthermore, their future projections are not supported by their analyses.

Sallenger, Asbury H., Jr.; Morton, Robert; Fletcher, Charles; Thieler, E. Robert; Howd, Peter

2000-01-01

409

Adaptive optics - Interaction matrix measurements and real time control algorithms for the COME-ON project  

Microsoft Academic Search

The servo-loop components and control algorithm of the COME-ON project involved in imaging in the near-infrared range with a 4-m telescope are described. Attention is focused on the wavelength sensor, wavefront computer, control computer, high-voltage amplifiers, and deformable and tip-tilt mirrors. An interaction matrix and its modal decomposition are discussed, along with modal filtering and tip-tilt control. It is pointed

Corinne Boyer; Vincent Michau; Gerard Rousset

1990-01-01

410

THE WEPP MODEL FOR RUNOFF AND EROSION PREDICTION UNDER SPRINKLER IRRIGATION  

Microsoft Academic Search

Potential runoff and erosion is a serious problem for some types of sprinkler irrigation systems, particularly traveling laterals and center pivots on medium- to heavy-textured soils operating on sloping land. Prediction of when runoff might occur is part of the system design process. The USDA-ARS Water Erosion Prediction Project (WEPP) model was tested with 3 years of field data under

D. C. Kincaid

411

Impact of climate change on soil erosion, runoff, and wheat productivity in central Oklahoma  

Microsoft Academic Search

The potential for global climate changes to increase the risk of soil erosion is clear, but the actual damage is not. The objectives of this study were to evaluate the potential impacts of climate change on soil erosion, surface runoff, and wheat productivity in central Oklahoma. Monthly projections were used from the Hadley Centre's general circulation model, HadCM3, using scenarios

X. C. Zhang; M. A. Nearing

2005-01-01

412

DWEPP: a dynamic soil erosion model based on WEPP source terms  

Microsoft Academic Search

A new rangeland overland-flow erosion model was developed based on Water Erosion Pre- diction Project (WEPP) sediment source and sink terms. Total sediment yield was estimated for rainfall simulation plots from the WEPP field experiments as well as for a small water- shed without a well developed channel network. Both WEPP and DWEPP gave a similar level of prediction accuracy

N. S. Bulygina; M. A. Nearing; J. J. Stone; M. H. Nichols

2007-01-01

413

Model development and applications at the USDA-ARS National Soil Erosion Research Laboratory  

Technology Transfer Automated Retrieval System (TEKTRAN)

The United States Department of Agriculture (USDA) has a long history of development of soil erosion prediction technology, initially with empirical equations like the Universal Soil Loss Equation (USLE), and more recently with process-based models such as the Water Erosion Prediction Project (WEPP)...

414

Does WEPP meet the specificity of soil erosion in steep mountain regions?  

Technology Transfer Automated Retrieval System (TEKTRAN)

We chose the USDA-ARS-WEPP model (Water Erosion Prediction Project) to describe the soil erosion in the Urseren valley (Central Switzerland) as it seems to be one of the most promising models for steep mountain environments. Crucial model parameters were determined in the field (slope, plant species...

415

3D seismic characterization of the Norwegian Channel Ice Stream - bedrock controls on ice streaming behaviour and spatio-temporal evolution of erosion and infill of a major cross-shelf trough through multiple glaciations  

NASA Astrophysics Data System (ADS)

The imprint of the Pleistocene glaciations in the North Sea Basin is known from various localities scattered across the North Sea Basin and to a large extent relies on widely spaced cored boreholes linked with 2D seismic profiles. Recent studies have demonstrated that a step change in levels of detail can be achieved when using 3D seismic data to image the glaciogenic sequences. However, to date only a relatively small part of the North Sea has been investigated with these data sets. Because of the long history of hydrocarbon exploration, the North Sea is now covered from coast to coast with high-quality 3D seismic data which allow the glacial succession to be examined in great spatio-temporal detail. This project used a regionally merged (c. 150 km by 150 km, 50 m bin spacing) 'mega survey' 3D seismic dataset to provide, for the first time, a 3D seismic geomorphological characterization of the Norwegian Channel Ice Stream, which records glaciations of the North Sea since at least 1.1 Ma. The project first linked the cored Troll borehole with the 3D seismic dataset, providing age and lithological calibrations of the ice stream base and key glacial surfaces within the fill. The interpretation was then extended to the greater survey extent. The basal ice stream footprint reveals a correlation between km-wide and tens of km long positive landform and dominantly sandy deposits in the substrate. The overall architecture of the infill reveals a progressive filling up of the eastern (proximal) part of the cross shelf trough whilst erosion dominated on the western (distal) flank. This evolution matches the evolution of the trough mouth fan situated on the Atlantic margin which shows a progressive westward migration of depocentres through the Pleistocene. On a smaller scale, the 3D seismic data display the interplay between fjord-supplied ice and the main ice stream conduit. Moreover the analysis suggests the occurrence of numerous grounded as well as floating glacial episodes, separated by marine sedimentation. Some of the marine inter-glacial units show evidence for tidal reworking and tidal cycles are depicted semi-quantitatively by sinuous iceberg scours. Importantly, the cross shelf trough provides a near complete record of glacial and interglacial sedimentation in a proximal setting which is available nowhere else, and yet there is only a single cored borehole within this archive. Clearly only full 3D coverage can ensure that future boreholes target the most complete sections including the oldest part of the ice stream fill which was not sampled in Troll, suggesting perhaps an even older origin of the basal erosion surface.

Grant, J.; Huuse, M.

2010-12-01

416

Inverting the Pendulum Using Fuzzy Control (Center Director's Discretionary Fund (Project 93-02)  

NASA Technical Reports Server (NTRS)

A single pendulum was simulated in software and then built on a rotary base. A fuzzy controller was used to show its advantages as a nonlinear controller since bringing the pendulum inverted is extremely nonlinear. The controller was implemented in a Motorola 6811 microcontroller. A double pendulum was simulated and fuzzy control was used to hold it in a vertical position. The double pendulum was not built into hardware for lack of time. This project was for training and to show advantages of fuzzy control.

Kissel, R. R.; Sutherland, W. T.

1997-01-01

417

Numerical modelling of erosion processes in the Himalayas of Nepal: effects of spatial variations of rock strength and precipitation  

E-print Network

Numerical modelling of erosion processes in the Himalayas of Nepal: effects of spatial variations'He`res, France Abstract: The interplay between tectonics and erosion has a predominant control on the evolution and hillslope land- sliding. We study the complex coupling existing between tectonics and erosion, with special

Demouchy, Sylvie

418

Predicting Soil Erosion for Alternative Land Uses Erda Wang, Chang Xin,* Jimmy R. Williams, and Cheng Xu  

E-print Network

Predicting Soil Erosion for Alternative Land Uses Erda Wang, Chang Xin,* Jimmy R. Williams runoff and soil erosion. Construction of a reservoir is the most effective strategy for controlling21 yr21 in the LP area (Ansai Statistical Bureau, 2003, p. 10­15). Research on soil erosion

419

Proceedings of the 2009 American Control Conference, St. Louis, MO, June 2009 Formation shape and orientation control using projected collinear  

E-print Network

and orientation control using projected collinear tensegrity structures Darren Pais, Ming Cao and Naomi Ehrich and rigidity properties inherent to tensegrity struc- tures, we first design a tensegrity-based, globally to stabilize a planar shape for a group of N vehicles using virtual tensegrity structures, where each vehicle

Leonard, Naomi

420

Cavitation erosion size scale effects  

NASA Technical Reports Server (NTRS)

Size scaling in cavitation erosion is a major problem confronting the design engineers of modern high speed machinery. An overview and erosion data analysis presented in this paper indicate that the size scale exponent n in the erosion rate relationship as a function of the size or diameter can vary from 1.7 to 4.9 depending on the type of device used. There is, however, a general agreement as to the values of n if the correlations are made with constant cavitation number.

Rao, P. V.; Buckley, D. H.

1984-01-01

421

High Voltage TAL Erosion Characterization  

NASA Technical Reports Server (NTRS)

Extended operation of a D-80 anode layer thruster at high voltage was investigated. The thruster was operated for 1200 hours at 700 Volts and 4 Amperes. Laser profilometry was employed to quantify the erosion of the thruster's graphite guard rings and electrodes at 0, 300, 600, 900, and 1200 hours. Thruster performance and electrical characteristics were monitored over the duration of the investigation. The guard rings exhibited asymmetric erosion that was greatest in the region of the cathode. Erosion of the guard rings exposed the magnet poles between 600 to 900 hours of operation.

Jacobson, David T.

2003-01-01

422

An holistic approach to beach erosion vulnerability assessment  

NASA Astrophysics Data System (ADS)

Erosion is a major threat for coasts worldwide, beaches in particular, which constitute one of the most valuable coastal landforms. Vulnerability assessments related to beach erosion may contribute to planning measures to counteract erosion by identifying, quantifying and ranking vulnerability. Herein, we present a new index, the Beach Vulnerability Index (BVI), which combines simplicity in calculations, easily obtainable data and low processing capacity. This approach provides results not only for different beaches, but also for different sectors of the same beach and enables the identification of the relative significance of the processes involved. It functions through the numerical approximation of indicators that correspond to the mechanisms related to the processes that control beach evolution, such as sediment availability, wave climate, beach morhodynamics and sea level change. The BVI is also intended to be used as a managerial tool for beach sustainability, including resilience to climate change impact on beach erosion.

Alexandrakis, George; Poulos, Serafim ?.

2014-08-01

423

Monitoring of gully erosion in the Central Ebro Basin by large-scale aerial photography taken from a remotely controlled blimp  

Microsoft Academic Search

Large deep gullies (Span. barrancos) are some of the most important sediment sources in the semi-arid environment of the Central Ebro Basin. They are incised into the Quaternary valley bottoms (Span. vales), which are characteristic landforms in this area. In the research project EPRODESERT (Evaluation of Processes Leading to Land Degradation and Desertification under Extensified Farming Systems), the development of

J. B. Ries; I. Marzolff

2003-01-01

424

Joint Power and Multiple Access Control for Wireless Mesh Network with Rose Projection Method  

PubMed Central

This paper investigates the utility maximization problem for the downlink of the multi-interface multichannel wireless mesh network with orthogonal frequency division multiple access. A cross-layer joint power and multiple access control algorithm are proposed. Rosen projection matrix is combined with Solodov projection techniques to build a three-memory gradient Rosen projection method, which is applied to solve this optimization problem. The convergence analysis is given and simulations show that the proposed solution achieves significant throughput compared with existing approaches. PMID:24883384

Tang, Meiqin; Shang, Lili; Xin, Yalin; Liu, Xiaohua; Wei, Xinjiang

2014-01-01

425

Experimental evidence for bedrock erosion by suspended sediment  

NASA Astrophysics Data System (ADS)

Fluvial bedrock incision influences channel evolution and sets the pace of landscape lowering. Bedrock incision often occurs via abrasion, and existing theory is divided on the erosional efficiency of sediment transported in suspension versus bed load, due in part to a lack of data to test model predictions. This represents a major knowledge gap as suspended sediment can account for the majority of the total fluvial sediment load, and untested models make opposite predictions of bedrock erosion in steep channels and during large floods. We performed controlled abrasion mill experiments examining suspended and bed load erosion, making use of an erodible polyurethane foam substrate as a bedrock analog to overcome previous experimental limitations and allow for measureable suspension erosion. Our results show foam erodes similar to natural rock, where erodibility is a function of tensile strength and density. To explore the role of the mode of sediment transport on erosion, we varied sediment size from gravel (42 mm diameter) to medium sand (0.4 mm diameter), while holding fixed hydraulics, sediment load, and substrate strength. Under these conditions, volumetric erosion rates decreased across the bed load (~101 - 103 cm3/hr) to suspended load (~0.01 - 100 cm3/hr) transition due to lower near-bed sediment concentrations (~25 g/l vs. 115 g/l), slower settling velocity (0.09 m/s vs. 0.49 m/s), and viscous damping of impacts (for particle Stokes numbers less than ~75) for suspended particles. Our results provide direct experimental evidence of erosion by suspended load, and upscaling results to field scale shows suspension erosion can outpace bed load erosion by up to a factor ~4 during large floods which suspend coarse sand and gravel, and where suspended sediment dominates the total load. These results imply that suspension erosion may also dominate on very steep slopes where commonly used bedrock incision models (which ignore suspension erosion) predict zero erosion. For small floods and low sloping channels where suspension is limited to sand, suspension erosion will have a reduced role because of comparatively low impact energies and viscously damped collisions.

Scheingross, J. S.; Brun, F.; Lo, D. Y.; Omerdin, K.; Lamb, M. P.

2013-12-01

426

30 CFR 816.45 - Hydrologic balance: Sediment control measures.  

...effluent limitations, (3) Minimize erosion to the extent possible. (b) Sediment...reclamation techniques are applied to reduce erosion and control sediment. Sediment control...disturbed areas so as not to cause additional erosion; (6) Using straw dikes,...

2014-07-01

427

30 CFR 816.45 - Hydrologic balance: Sediment control measures.  

Code of Federal Regulations, 2013 CFR

...effluent limitations, (3) Minimize erosion to the extent possible. (b) Sediment...reclamation techniques are applied to reduce erosion and control sediment. Sediment control...disturbed areas so as not to cause additional erosion; (6) Using straw dikes,...

2013-07-01

428

30 CFR 817.45 - Hydrologic balance: Sediment control measures.  

...effluent limitations, (3) Minimize erosion to the extent possible. (b) Sediment...reclamation techniques are applied to reduce erosion and control sediment. Sediment control...disturbed areas so as not to cause additional erosion; (6) Using straw dikes,...

2014-07-01

429

30 CFR 817.45 - Hydrologic balance: Sediment control measures.  

Code of Federal Regulations, 2011 CFR

...effluent limitations, (3) Minimize erosion to the extent possible. (b) Sediment...reclamation techniques are applied to reduce erosion and control sediment. Sediment control...disturbed areas so as not to cause additional erosion; (6) Using straw dikes,...

2011-07-01

430

30 CFR 817.45 - Hydrologic balance: Sediment control measures.  

Code of Federal Regulations, 2013 CFR

...effluent limitations, (3) Minimize erosion to the extent possible. (b) Sediment...reclamation techniques are applied to reduce erosion and control sediment. Sediment control...disturbed areas so as not to cause additional erosion; (6) Using straw dikes,...

2013-07-01

431

Effects of grazing management on stream bank erosion  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cattle grazing in riparian areas may contribute to sediment and nutrient loading of surface waters. A project was conducted to establish the effects of cattle grazing on stream bank erosion. Six 30-acre cool-season grass pastures, each bisected by a 642-foot stream segment, were assigned one of thr...

432

Mechanics of interrill erosion with wind-driven rain  

Technology Transfer Automated Retrieval System (TEKTRAN)

The vector physics of wind-driven rain (WDR) differs from that of wind-free rain, and the interrill soil detachment equations in the Water Erosion Prediction Project (WEPP) model were not originally developed to deal with this phenomenon. This article provides an evaluation of the performance of the...

433

Mechanics of Interrill Erosion with Wind-Driven Rain (WDR)  

Technology Transfer Automated Retrieval System (TEKTRAN)

This article provides an evaluation analysis for the performance of the interrill component of the Water Erosion Prediction Project (WEPP) model for Wind-Driven Rain (WDR) events. The interrill delivery rates (Di) were collected in the wind tunnel rainfall simulator facility of the International Cen...

434

Erosive diseases of the vulva.  

PubMed

Vesicobullous and inflammatory diseases produce vulvar erosions that may exhibit nonspecific morphology and represent a diagnostic challenge. An approach to arriving at the correct diagnosis is presented. Most common etiologies are reviewed. PMID:20883917

Pipkin, Clare

2010-10-01

435

A Wind Erosion Equation1  

Microsoft Academic Search

ABSTRACT The amount of erosion, E, expressed in tons per acre per annum, that will occur from a given agricultural field can be expressed in terms of equivalent variables as: E = , is field length along the prevailing wind erosion direction, and V is equivalent quantity of vegetative cover. The 5 equivalent variables are obtained,by grouping,some,and,converting,others of the,11 primary

N. P. Woodruff; F. H. Siddoway

1965-01-01

436

Test Your Stream Erosion IQ  

NSDL National Science Digital Library

Test Your Stream Erosion IQ is an online activity for students to examine topographical maps of stream erosion, and identify the type of landforms that would be created by the stream channels shown on the maps. From the elevation contour lines, students decide if the dome, mountain peak, U-shaped canyon, irregular, or V-shaped canyon landforms are represented. There are also photographs to illustrate the landforms.

437

Stimulation Controls and Mitigation of Induced Seismicity for EGS Project: Examples from the Newberry EGS Demonstration Project (Invited)  

NASA Astrophysics Data System (ADS)

Creating an EGS reservoir depends upon injection induced seismicity (IIS) to create fracture permeability and allow the reservoir to be mapped using passive microseismic monitoring. However, in some cases, the seismicity induced through the stimulation has been felt by surrounding populations and in one case caused sufficient concern to force shut-down of the project. AltaRock Energy, Inc. is working with universities, national labs and consultants on the Newberry Volcano EGS Demonstration Project (Funded in part through a grant from the US DOE: DE-EE0002777). This project will attempt to stimulate a very low permeability existing deep geothermal well with high temperature to develop a circulating geothermal system that be able to sustain production of economic quantities of hot water and steam for power production. In order to allay concerns that IIS might become hazardous at Newberry, AltaRock Energy has agreed to a robust series of safeguards and mitigation controls. The safeguards detail how the EGS stimulation will be monitored and under what circumstances the stimulation should be safely reduced or halted to avoid perceptible seismic events that would alarm or possibly cause damage to the local community. The International Energy Agency (IEA) Implementing Agreement for a Cooperative Programme on Geothermal Energy Research and Technology, or Geothermal Implementing Agreement (GIA), developed an induced seismicity mitigation protocol which has been adopted by the US Department of Energy for their funded EGS Demonstration Projects. AltaRock is the process of making this protocol site specific for the Newberry project.The Notice of Intent (NOI) to the BLM for the Newberry EGS Demonstration includes plans to conduct an induced seismicity hazards and risk assessment. These plans include implementing the Protocol for Induced Seismicity Associated with Geothermal System (Majer et al., 2008), adopted by the International Energy Agency. The theory of IIS has recently advanced due to the data and experience collected at EGS projects worldwide. One of the most promising areas of research has been the development of a seismogenic index by Dr. Serge Shapiro and colleagues at Freie Universität Berlin. This index (Table 1) may provide a means to relate measurable geomechanical parameters and total injected volume to the probability of generating a seismic event with a magnitude greater than a tolerable threshold.Table 1: Seismogenic Indices 1Estimated from Figure 3 of Shapiro et al. (2010). 2Values will be determined for other sites based on additional data gathering, sensitivity analysis and consultation with Dr. Shapiro.

Petty, S.; Cladouhos, T. T.; Osborn, W.; Iovenitti, J.

2010-12-01

438

Public Information Campaign: Soil Erosion, Conservation, and Watershed Health  

NSDL National Science Digital Library

Students in groups of two create a 4-minute educational video, brochure, and poster on an aspect of soil erosion, soil conservation, and/or watershed health for agricultural regions within the midwestern states. This is a half term project and the materials are presented in a forum towards the end of the semester. The project is aimed to help students learn to pitch science to a wide audience and provide practice (indirectly) applying scientific principles to conservation efforts.

Szramek, Kathryn

439

A homotopy algorithm for digital optimal projection control GASD-HADOC  

NASA Technical Reports Server (NTRS)

The linear-quadratic-gaussian (LQG) compensator was developed to facilitate the design of control laws for multi-input, multi-output (MIMO) systems. The compensator is computed by solving two algebraic equations for which standard closed-loop solutions exist. Unfortunately, the minimal dimension of an LQG compensator is almost always equal to the dimension of the plant and can thus often violate practical implementation constraints on controller order. This deficiency is especially highlighted when considering control-design for high-order systems such as flexible space structures. This deficiency motivated the development of techniques that enable the design of optimal controllers whose dimension is less than that of the design plant. A homotopy approach based on the optimal projection equations that characterize the necessary conditions for optimal reduced-order control. Homotopy algorithms have global convergence properties and hence do not require that the initializing reduced-order controller be close to the optimal reduced-order controller to guarantee convergence. However, the homotopy algorithm previously developed for solving the optimal projection equations has sublinear convergence properties and the convergence slows at higher authority levels and may fail. A new homotopy algorithm for synthesizing optimal reduced-order controllers for discrete-time systems is described. Unlike the previous homotopy approach, the new algorithm is a gradient-based, parameter optimization formulation and was implemented in MATLAB. The results reported may offer the foundation for a reliable approach to optimal, reduced-order controller design.

Collins, Emmanuel G., Jr.; Richter, Stephen; Davis, Lawrence D.

1993-01-01

440

Feedback control of a solid-state qubit using high-fidelity projective measurement.  

PubMed

We demonstrate feedback control of a superconducting transmon qubit using discrete, projective measurement and conditional coherent driving. Feedback realizes a fast and deterministic qubit reset to a target state with 2.4% error averaged over input superposition states, and allows concatenating experiments more than 10 times faster than by passive initialization. This closed-loop qubit control is necessary for measurement-based protocols such as quantum error correction and teleportation. PMID:23368293

Ristè, D; Bultink, C C; Lehnert, K W; DiCarlo, L

2012-12-14

441

Three Gorges Reservoir Area: soil erosion under natural condition vs. soil erosion under current land use  

NASA Astrophysics Data System (ADS)

Apparently, the current most prominent human-induced example for large scale environmental impact is the Three Gorges Dam in China. The flooding alongside the Yangtze River, and its tributaries results in a vast loss of settlement and farmland area with productive, fertile valley soils. Due to the associated high land use dynamic on uphill-sites, the soil resources are underlying high land use pressure. Within our study, the soil erosion under natural conditions is compared to the soil erosion under current land use after the impoundment. Both were modeled using the empirical Universal Soil Loss Equation (USLE) which is able to predict long-term annual soil loss with limited data. The database consists of digital terrain data (45 m resolution DEM, erosive slope length based on Monte-Carlo-Aggregation according to Behrens et al. (2008)), field investigations of recent erosion forms, and literature studies. The natural disposition to soil erosion was calculated considering the USLE factors R, S, and K. The soil erosion under current land use was calculated taking into account all USLE factors. The study area is the catchment of the Xiangxi River in the Three Gorges Reservoir area. Within the Xiangxi Catchment (3,200 km²) the highly dynamic backwater area (580 km²), and two micro-scale study sites (Xiangjiaba with 2.8 km², and Quyuan with 88 km²) are considered more detailed as they are directly affected by the river impoundment. Central features of the Xiangxi Catchment are the subtropical monsoon climate, an extremely steep sloping relief (mean slope angle 39°, SD 22.8°) artificially fractured by farmland terraces, and a high soil erodibility (mean K factor 0.37, SD 0.13). On the catchment scale the natural disposition to soil erosion makes up to mean 518.0 t ha-1 a-1. The maximum potential soil loss of 1,730.1 t ha-1 a-1 under natural conditions is reached in the Quyuan site (mean 635.8 t ha-1 a-1) within the backwater area (mean 582.9 t ha-1 a-1). In the Xiangjiaba site (mean 640.1 t ha-1 a-1) the maximum soil erosion of 1,115.4 t ha-1 a-1 under natural conditions is negligible lower. Compared to these erosion rates the mean soil loss under current land use is considerably lower (Xiangxi Catchment: mean 161.5 t ha-1 a-1; Backwater area: mean 166.3 t ha-1 a-1; Quyuan: mean 211.2 t ha-1 a-1; Xiangjiaba: mean 158.6 t ha-1 a-1). However, soil loss of maximum 2,662.2 t ha-1 a-1 for Xiangxi Catchment, 2,397.9 t ha-1 a-1 for the backwater area, 1,689.9 t ha-1 a-1 for Quyuan site, and 957.1 t ha-1 a-1 for Xiangjiaba site are also potentially possible. According to the Chinese Soil Erosion Rate Standard (cf. Xu et al., 2008) almost 44 % of the area of the Xiangxi Catchment show extreme (> 80 t ha-1 a-1) soil erosion which mainly occur in the backwater area. Our results show that the Xiangxi Catchment is already highly prone to soil erosion under natural conditions. In places, the current land use in the mountainous relief of the Xiangxi Catchment still increases the potential soil erosion to an extreme high level. However, mean potential soil loss rates under current land use lie under those due to the natural disposition. This is due to the fact that the natural disposition to soil erosion does not consider the complete topography factor (LS factor), that effects the potential soil loss (R² = 0.77) by the human-influenced erosive slope length through farmland terraces. Moreover, our results indicate an urgent need of proper management and conservation decisions in order to reduce soil erosion against the background of a high land use dynamic in a region with low carrying capacity (Beattie, 2002). Literature Beattie, J. (2002): Dam Building, Dissent, And Development: The Emergence Of The Three Gorges Project. New Zealand Journal of Asian Studies, Vol. 4(1): 138-158. Behrens, T., Schmidt, K. and Scholten, T. (2008). An approach to remove uncertainties in nominal environmental covariates and soil class maps. In: Hartemink, A. E., McBratney, A. and M. de L. Mendoca-Santos (2008): Digital Soil Mapping for regions and coun

Schönbrodt, Sarah; Behrens, Thorsten; Scholten, Thomas

2010-05-01

442

Area specificity and topography of thalamocortical projections are controlled by ephrin/Eph genes.  

PubMed

The mechanisms generating precise connections between specific thalamic nuclei and cortical areas remain poorly understood. Using axon tracing analysis of ephrin/Eph mutant mice, we provide in vivo evidence that Eph receptors in the thalamus and ephrins in the cortex control intra-areal topographic mapping of thalamocortical (TC) axons. In addition, we show that the same ephrin/Eph genes unexpectedly control the inter-areal specificity of TC projections through the early topographic sorting of TC axons in an intermediate target, the ventral telencephalon. Our results constitute the first identification of guidance cues involved in inter-areal specificity of TC projections and demonstrate that the same set of mapping labels is used differentially for the generation of topographic specificity of TC projections between and within individual cortical areas. PMID:12895420

Dufour, Audrey; Seibt, Julie; Passante, Lara; Depaepe, Vanessa; Ciossek, Thomas; Frisén, Jonas; Kullander, Klas; Flanagan, John G; Polleux, Franck; Vanderhaeghen, Pierre

2003-07-31

443

The Autonomous Blimp Project of LAAS-CNRS: Achievements in Flight Control and Terrain Mapping  

Microsoft Academic Search

In this paper we provide a progress report of the LAAS-CNRS project of autonomous blimp robot development, in the context of field robotics. Hardware developments aimed at designing a generic and versatile experimental platform are first presented. On this base, the flight control and terrain mapping issues, which constitute the main thrust of the research work, are presented in two

Emmanuel Hygounenc; Il-kyun Jung; Philippe Souères; Simon Lacroix

2004-01-01

444

78 FR 64909 - Southwestern Region: Invasive Plant Control Project, Carson and Santa Fe National Forests, New...  

Federal Register 2010, 2011, 2012, 2013

...Control Project, Carson and Santa Fe National Forests, New Mexico...NOI) in the Federal Register (65 FR 78464) to prepare an environmental...plants in the Carson and Santa Fe National Forests. The agency...carson/landmanagement Santa Fe National Forest:...

2013-10-30

445

Role of projection in the control of bird flocks Daniel J. G. Pearcea,b  

E-print Network

Role of projection in the control of bird flocks Daniel J. G. Pearcea,b , Adam M. Millera) Swarming is a conspicuous behavioral trait observed in bird flocks, fish shoals, insect swarms, and mammal that such local interactions alone are insufficient to explain the organization of large flocks of birds

Turner, Matthew

446

Interface control document between PFP Transition Project and Solid Waste Disposal Division  

SciTech Connect

This interface control document between Plutonium Finishing Plant (PFP) Transition Project and Solid Waste Disposal (SWD) establishes the functional responsibilities of each division where interface exist between the two divisions. The document includes waste volumes and timing for use in planning the proper waste management capabilities.

Venetz, T.J.

1995-01-13

447

Audio Conductor The Audio Conductor project aims to give users control  

E-print Network

Audio Conductor The Audio Conductor project aims to give users control of prerecorded music in real and gyroscope data back to a central unit. The central unit consists of an FPGA, which manages the audio and song selection can be recognized. The tempo of the output audio is then modified to match the user

Hero, Alfred O.

448

Statistical control of manufacturing cycle time and project time: lessons from statistical process control  

Microsoft Academic Search

A manufacturing cycle includes all activities from order processing to shipping. The benefits of reducing cycle time includes increased productivity and added competitive advantage. This paper proposes a new approach to the control of cycle time variability in the short-term and the reduction of cycle time in the long-term. It has been said that when the control and stability of

PAUL M. SWAMIDASS; CLYDE MAJERUS

1991-01-01

449

Examine an example of wave erosion  

NSDL National Science Digital Library

This series of photographs presents an example of wave erosion to middle and high school students. The five images, dated from 1890 to 1990, depict the demise of an actual sea stack near Newport, Oregon. The introduction explains how sea stacks begin as part of an outcropping of land such as a cliff and how they are gradually eroded by the waves. A pop-up window shows the location the original sea stack on a map of the United States. Movie controls allow students to repeat or pause the succession of images, which can give students more time to analyze and compare the images. Copyright 2005 Eisenhower National Clearinghouse

Education, Terc. C.; Littell, Mcdougal

2003-01-01

450

The shape and erosion of pebbles  

E-print Network

The shapes of flat pebbles may be characterized in terms of the statistical distribution of curvatures measured along their contours. We illustrate this new method for clay pebbles eroded in a controlled laboratory apparatus, and also for naturally-occurring rip-up clasts formed and eroded in the Mont St.-Michel bay. We find that the curvature distribution allows finer discrimination than traditional measures of aspect ratios. Furthermore, it connects to the microscopic action of erosion processes that are typically faster at protruding regions of high curvature. We discuss in detail how the curvature may be reliable deduced from digital photographs.

D. J. Durian; H. Bideaud; P. Duringer; A. Schroder; C. M. Marques

2006-07-05

451

An Economic Analysis of Erosion and Sedimentation in Lavon Reservoir Watershed  

E-print Network

potential agricultural NPS pollution controls in the watershed above Lavon Reservoir. The study focuses on: (a) effects of erosion controls on farm income, (b) off-side sediment damages in the watersheds; (c) costs of administering and enforcing alternative...

Taylor, C. R.; Reneau, D. R.; Harris, B. L.

452

An Economic Analysis of Erosion and Sediment Damage in the Lower Running Draw Watershed  

E-print Network

of a study on the economic impact of implementing potential agricultural NPS pollution controls in Lower Running Water Draw watershed. The study focuses on: (a) the effects of erosion control on farm income, (b) off-site sediment damages...

Reneau, D. R.; Taylor, C. R.; Harris, B. L.; Lacewell, R. D.; Mueller, P. E.

453

BCAUS Project description and consideration of separation of data and control  

NASA Technical Reports Server (NTRS)

The commonly stated truths that data may be segregated from program control in generic expert system shells and that such tools support straightforward knowledge representation were examined. The ideal of separation of data from program control in expert systems is difficult to realize for a variety of reasons. One approach to achieving this goal is to integrate hybrid collections of specialized shells and tools instead of producing custom systems built with a single all purpose expert system tool. Aspects of these issues are examined in the context of a specific diagnostic expert system application, the Backup Control Mode Analysis and Utility System (BCAUS), being developed for the Gamma Ray Observatory (GRO) spacecraft. The project and the knowledge gained in working on the project are described.

Bush, Joy L.; Weaver, Steven J.

1989-01-01

454

Surface Erosion and Flow  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Released 7 April 2003

The mottled surface texture and flow features observed in this THEMIS image suggest materials may be, or have been, mixed with ice. There is also evidence in some areas for infilling of sediments as crater rims and ridges appear covered.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

Image information: VIS instrument. Latitude 45.3, Longitude 48.8 East (311.2 West). 19 meter/pixel resolution.

2003-01-01

455

Composite Erosion by Computational Simulation  

NASA Technical Reports Server (NTRS)

Composite degradation is evaluated by computational simulation when the erosion degradation occurs on a ply-by-ply basis and the degrading medium (device) is normal to the ply. The computational simulation is performed by a multi factor interaction model and by a multi scale and multi physics available computer code. The erosion process degrades both the fiber and the matrix simultaneously in the same slice (ply). Both the fiber volume ratio and the matrix volume ratio approach zero while the void volume ratio increases as the ply degrades. The multi factor interaction model simulates the erosion degradation, provided that the exponents and factor ratios are selected judiciously. Results obtained by the computational composite mechanics show that most composite characterization properties degrade monotonically and approach "zero" as the ply degrades completely.

Chamis, Christos C.

2006-01-01

456

Revisiting the golden triangle of cost, time and quality: the role of NPV in project control, success and failure  

Microsoft Academic Search

The paper examines the relationship between project budgets, cash flow, cost control and time schedules. It considers the theoretical effect that each can have on the net present value (NPV) of a project. The paper proposes that investment appraisal techniques, such as NPV, can and should be used as an ongoing monitor of project health. Finally, the theoretical points are

Paul D Gardiner; Kenneth Stewart

2000-01-01

457

Slope erosion estimation in the river basin of the boreal zone of the East Russian Plain  

NASA Astrophysics Data System (ADS)

INTRODUCTION Multi-factor controls of erosion processes determine the complexity of erosion-affected hillslope geosystem functioning. Relationships between erosion and its major controls change in geographical space, so that slope erosion regimes vary regionally, being determined by landscape conditions. Problems with the quantitative assessment of all types of soil erosion from raindrop to gullies still require a satisfactory solution. In this paper we propose to consider the entire complexity of hillslope erosion processes as a unit termed "basin erosion". The focus of this paper is on the methodological aspects of revealing the roles different landscape conditions play in causing basin erosion. The East Russian Plain was chosen as the investigation region due to the wide distribution of a spectrum of erosion processes in the region. It is also where the so-called "Erosion Pole" of European Russia is situated. During the last 200 years arable land cover has increased by 40-60% and now comprises about 80-85% of basins area. The period of most intensive agriculture in the region began about 200 years ago. Different combinations of natural and anthropogenic conditions create geocomplexes of different taxonomic levels known as "landscapes". Depending on the degree to which erosion processes are generalized in an investigation, it is necessary to use different geosystem taxon as the basic unit. To evaluate the role different landscape factors play in the development of human-accelerated basin erosion, a landscape map of the East Russian Plain was created. DATA The study territory is located within the forest, forest-steppe and northern part of steppe landscape zone of the Russian Plain and comprises more than 130 000 km2. The total number of parameters used for landscape regionalization comprised more than 50 (including: hydro-climatic, geomorphological, anthropogenic, lithological and landscape-geophysical); 3331 river basins were examined with an average catchment area of 40 km2. METHODS The method of "self-organizing maps of Kohonen" was used as the main approach for automatic regionalization. RESULTS Spatial analyses of soil erosion and gullying intensity in the study region based on available information allows us to conclude that: maximum basin erosion is characteristic for upland landscapes of broad-leaved forest zones (Sub-boreal) and the southern part of mixed forest zone; its intensity decreases in both western and eastern directions; to the north and to the south from upland landscapes of broad-leaved forest zones we can also observe lowering of basin erosion intensity; in the north it happens because of lower agricultural activity, and to the south it is due to development of chernozem soils more stable to erosion; and zonality is typical for soil erosion processes.

Yermolaev, O.

2012-04-01

458

Channels and Erosion  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Released 20 June 2003

The dissected and eroded channel observed in this THEMIS image taken of plains materials southwest of the volcano Elysium Mons shows typical erosional islands and depositional features. The interesting thing about this channel is that it appears to start out of nowhere. The MOLA context image shows that the channel originates from a fissure within the ground, whose origin is likely volcanic, but may also be related to volatile processes.

Image information: VIS instrument. Latitude 19.5, Longitude 126.8 East (233.2 West). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2003-01-01

459

Deposition + Erosion = Textures  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Released 7 May 2003

Toward the westernmost extent of the Medusae Fossae Formation, a 5000+ km long belt of eroding sediments, the interleaving of erosional surfaces produces dramatic textural variations. In the lower third of this image, the cross-hatched MFF layer is being stripped back from a surface that was already heavily eroded before the MFF layer was deposited. Also, note the sinuous and, in places, dendritic ridges that are either linear dunes or inverted channels.

Image information: VIS instrument. Latitude -3.9, Longitude 154.1East (205.9). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2003-01-01

460

Erosion from a complex watershed  

E-print Network

tora". Engineer'ing EROS1ON FROM A COMPLEX WATERSHED A Thesis by HSIEN-CHIEN KUH Approved as to style and content by: (Chai rman of Committee) (Head of Oepartm nt) (M. mber) (I'lembet ) ( mber) August 1976 ABSTRACT Erosion From a Complex... Watershed. (August, 1976) Hsien-chien Kuh, B. S. , Tamkang College of Arts and Science, Tamsui, Taiwan, Republic of China Chairman of Advisory Committee: Dr. E. A. Hiler Erosion from watersheds is a complex and accumulated process and a major source...

Kuh, Hsien-chien

2012-06-07

461

Wind, rain and soil erosion rates on bare and plant covered agriculture plots at the experimental station of El Teularet -Sierra de Enguera, Eastern Spain  

NASA Astrophysics Data System (ADS)

Soil erosion is being scientifically researched for more tan one century, but there is some knowledge lacks that should be researched. Within the factors of the soil erosion wind and rain were studied, but little is know about the impact of the combination of both. Soil erosion by wind was mainly studied on drylands and agriculture land (Sterk and Spaan, 1997; Bielders et al., 2002; Rajot et al., 2003; Zobeck et al., 2003). Soil erosion by water was studied in many ecosystems but it is especially active on agriculture land (Cerdà et al., 2009) and under Mediterranean climatic conditions (Cerdà et al., 2010). The importance of wind on soil erosion is base in the fact that rainstorms occurs with wind, adding a driving component to the falling raindrops. The influence of wind on raindrops is clear, but there is not measurements and there is no information of this influence under field conditions with natural rainfall events.This paper aims to determine the interaction between wind and rain as factors of the soil losses under Mediterranean climatic conditions and different agriculture managements and land uses. Since 2003, the El Teularet-Serra de Enguera Soil Erosion Experimental Station located in Eastern Spain is measuring the soil losses in plots under different land uses and land managements. The station is devoted to study the soil water erosion processes under rain-fed agriculture fields and the rangelands by means of simulated rainfall experiments and plots of different sizes. The soil erosion measure ments are done by means of 13 plots, each of them composed of 5 subplots of 1, 2, 4, 16 and 48 m2 under different land uses and managements. Two plots are covered by two different types of shrubs: Quercus coccifera and Ulex parviflorus, respectively. Three plots reproduce the use of herbicides, one is ploughed, and three plots follow conservation practices (oats and beans with no-tillage, with tillage, and with a vege- tation cover of weeds). Other plots are covered with straw, chipped branches of olive and with a geotextil developed specifically to control erosion on agricultural fields. The Soil Erosion Experimental Station of the El Teularet-Serra de Enguera is located in Eastern Spain. The station is devoted to study the soil water erosion processes under rain-fed agriculture fields and the rangelands. Agriculture is the main source of sedi ments on the mountainous areas of Spain due to the current management. The exper imental station of the El Teularet-Sierra de Enguera is composed also of a meteorological station with tipping-bucket raingauges (0.2 mm), and sensors that measure soil and air moisture and temperature, wind direction and speed and the sun radiation connected to a data-logger that record these data every five minutes. This paper will review the data collected during the period 2004 to 2011 in order to determine if the wind direction and wind speed determined the soil erosion rates. In this way it will be clarified the infliuence of wind on the soil erosion processes.The results will be compared to the measurement collected at the Montesa experimental station devoted to the study of soil erosion on citrus orchards. The experimental setup within the citrus plantation is being supported by the research project CGL2008- 02879/BTE.

Cerdà, A.; Azorin-Molina, C.; Iserloh, Th.

2012-04-01

462

Galveston Island and erosion  

E-print Network

. VITA 73 74 80 85 97 101 115 LIST OF TABLES Table Page 1. Ai rphoto Scale Determination with the Aid of a Base Map . . 16 2. Actual-vs-l4easured Photo Scale and Resulting Error 3. Tropical Cyclones Affecting the Texas Coast from 1952...-1983 17 64 4. Projected Sea-level Rise 72 5. Potential Sand Sources and Sinks for Galveston Island . . . . 80 Al. Vegetation-line Changes on West Beach from July 3, 1977 to September 22, 1983; Impact of Recent Storm Events AZ. Changes...

Bolleter, Jim Mason

2012-06-07

463

Erosional consequence of saltcedar control.  

PubMed

Removal of nonnative riparian trees is accelerating to conserve water and improve habitat for native species. Widespread control of dominant species, however, can lead to unintended erosion. Helicopter herbicide application in 2003 along a 12-km reach of the Rio Puerco, New Mexico, eliminated the target invasive species saltcedar (Tamarix spp.), which dominated the floodplain, as well as the native species sandbar willow (Salix exigua Nuttall), which occurred as a fringe along the channel. Herbicide application initiated a natural experiment testing the importance of riparian vegetation for bank stability along this data-rich river. A flood three years later eroded about 680,000 m(3) of sediment, increasing mean channel width of the sprayed reach by 84%. Erosion upstream and downstream from the sprayed reach during this flood was inconsequential. Sand eroded from channel banks was transported an average of 5 km downstream and deposited on the floodplain and channel bed. Although vegetation was killed across the floodplain in the sprayed reach, erosion was almost entirely confined to the channel banks. The absence of dense, flexible woody stems on the banks reduced drag on the flow, leading to high shear stress at the toe of the banks, fluvial erosion, bank undercutting, and mass failure. The potential for increased erosion must be included in consideration of phreatophyte control projects. PMID:19548024

Vincent, Kirk R; Friedman, Jonathan M; Griffin, Eleanor R

2009-08-01

464

Rain Erosion-Does the Rate of Water Effect Erosion?  

NSDL National Science Digital Library

This activity is a guided inquiry investigation where students gather data on rate of water falling on erosion. Student will interpret their data, and develop a conclusion from the data. The data will lead to further questions, which can be developed by the students.

Johnson, Kyle