Open Access. Powered by Scholars. Published by Universities.®

Operations Research, Systems Engineering and Industrial Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

University of Nebraska - Lincoln

Discipline
Keyword
Publication Year
Publication
Publication Type

Articles 631 - 660 of 764

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

In-Channel Sediment Basins: An Alternative To Dam-Style Debris Basins, Wendy S. Gist, Scott E. Stonestreet, Ronald R. Copeland Jan 1992

In-Channel Sediment Basins: An Alternative To Dam-Style Debris Basins, Wendy S. Gist, Scott E. Stonestreet, Ronald R. Copeland

United States Army: Publications

In-channel sediment basins were designed, in lieu of a traditional debris basin, to capture large sediment loads at the upstream end of a proposed flood control channel. A numerical model, HEC-6, was used to size the basins.


Numerical Modeling Of Reservoir Tailrace Hydraulics For Water Quality And Habitat Analysis, Brad R. Hall, John Nestler Jan 1992

Numerical Modeling Of Reservoir Tailrace Hydraulics For Water Quality And Habitat Analysis, Brad R. Hall, John Nestler

United States Army: Publications

The Waterways Experiment Station has developed dynamic numerical hydraulic and water quality simulation models of the Missouri River reaches downstream of Fort Peck, Garrison, and Fort Randall Dams in support of Master Water Control Manual studies. The numerical modeling approach is to compute spatial and temporal variations in stage and discharge in each of these reaches using UNET, a one-dimensional dynamic flow model. Hydraulic and geometric parameters calculated by UNET are then linked with transport algorithms in the CE-QUAL-RIV1 numerical model for computing spatial and temporal variation in water temperature and dissolved oxygen in each of the modeled reaches. Parameters …


Development Of A Comprehensive Modeling System For Remediation Of Contaminated Groundwater, Jeffrey P. Holland Jan 1992

Development Of A Comprehensive Modeling System For Remediation Of Contaminated Groundwater, Jeffrey P. Holland

United States Army: Publications

The U.S. Army Engineer Waterways Experiment Station (WES) has proposed development of a Groundwater Modeling System (GMS) for simulating groundwater flow, the transport/fate of subsurface contaminants, and the efficacy of remedial actions. The GMS is proposed to support the needs of the U.S. Army in three main areas: site characterization, contamination assessment, and evaluation of remediation alternatives. To do this, the GMS will include numerical algorithms for simulating the hydrogeologic and biogeochemical processes that must be considered when developing remediation programs for Army and other sites. An essential feature of the GMS will be user interfaces which augment model application …


Modeling Dredged Material Disposed In Open Water, B. H. Johnson, D. N. Mccomas, D. C. Mcvan Jan 1992

Modeling Dredged Material Disposed In Open Water, B. H. Johnson, D. N. Mccomas, D. C. Mcvan

United States Army: Publications

Physical model disposal tests at a 1:50 scale have been conducted to provide guidance on numerical model developments and to provide data sets for numerical model verification. These tests have been conducted with a model split-hull barge and a multibin hopper vessel. Both stationary and moving disposals have been monitored. Results imply that the bulk behavior of the disposal material in both the descent and bottom surge phases can be approximately scaled to the prototype. Visual observations have resulted in modifications to an existing numerical model such that the disposal is represented by a series of downward convecting clouds from …


An Acoustic Impedance Method For Subbottom Material Characterization, Richard G. Mcgee, Robert F. Ballard, Jr. Jan 1992

An Acoustic Impedance Method For Subbottom Material Characterization, Richard G. Mcgee, Robert F. Ballard, Jr.

United States Army: Publications

This paper discusses modified seismic reflection technique tailored to the characterization of bottom and subbottom materials. The application of acoustic impedance principles has resulted in the development of a method for rapidly determining the type and density of subbottom materials scheduled for dredging. Acoustic theory is discussed only in sufficient detail to enable the reader to understand basic concepts.


Overtopping Protection Alternatives For Dams, Noel R. Oswalt Jan 1992

Overtopping Protection Alternatives For Dams, Noel R. Oswalt

United States Army: Publications

A reevaluation of design floods for dam safety within the united states showed that the need to modify dams to accommodate larger floods has greatly increased in recent years. The occurrence of larger design floods would result in overtopping of the dams at many existing reservoirs due to insufficient storage or release capacity. When the addition of storage or release capacity becomes impractical or too costly, dam owners must sometimes resort to providing overtopping protection.
An ASCE Hydraulics Division Task committee on Alternatives for Overtopping Protection for Dams was established in 1991 to inventory and evaluate modification alternatives for new, …


A Numerical Simulation Approach To Estimating Disposal Site Stability, Norman W. Sheffner Jan 1992

A Numerical Simulation Approach To Estimating Disposal Site Stability, Norman W. Sheffner

United States Army: Publications

A systematic methodology is described for estimating the long-term response of a dredged material site to local environmental forcings. The methodology is based on the development of user-accessible data bases of wave and current time series and the subsequent application of these boundary conditions to coupled hydrodynamic, sediment transport, and bathymetry change models. The approach was developed to provide an estimate of long-term material fate for use in determining whether an existing or proposed disposal site will be dispersive or nondispersive over periods of time on the order of months to years.


Reduced Recharge Capacity Of A Pump And Treat System, Cynthia L. Teeter, Douglas Gunnison, Norman R. Francingues, Mark E. Zappi Jan 1992

Reduced Recharge Capacity Of A Pump And Treat System, Cynthia L. Teeter, Douglas Gunnison, Norman R. Francingues, Mark E. Zappi

United States Army: Publications

The North Boundary treatment system at Rocky Mountain Arsenal (RMA), Commerce City, Colorado, involves pumping of contaminated groundwater from an unconfined aquifer from one side of a soil-bentonite (SB) slurry wall to three pulsed-bed activated carbon adsorbers and prefilter and postfilter systems. The treated water is injected into the unconfined aquifer on the other side of the slurry wall via 38 recharge wells and 15 recharge trenches, collectively referred to as the recharge system. Recharge capacity of the recharge system has declined over time, limiting the operating capacity of the system. Two probable causes for reduction of the recharge systems …


Design Of Pneumatic Diffuser System, Steven C. Wilhelms, Charles W. Downer, Richard E. Price Jan 1992

Design Of Pneumatic Diffuser System, Steven C. Wilhelms, Charles W. Downer, Richard E. Price

United States Army: Publications

During non-generation periods, leakage through the wicket gates of a hydroturbine often results in very poor quality water (low or zero dissolved oxygen) in the tailrace of the hydropower facility. Generally, the leakage rate is relatively small, usually about 5-10 cfs per turbine. A bottom-mounted diffuser system was designed based on laboratory-measured and manufacturer-supplied specifications about the gas transfer characteristics of the bubble plume generated by an 11- inch flexible head diffuser. The design criteria and the overall effectiveness of the system were evaluated in field tests at Lake Eufaula, Oklahoma. The analysis of field data is reported herein.


Treatment Of Contaminated Groundwater Using Chemical Oxidation, Mark E. Zappi, Beth C. Fleming, M. John Cullinane Jan 1992

Treatment Of Contaminated Groundwater Using Chemical Oxidation, Mark E. Zappi, Beth C. Fleming, M. John Cullinane

United States Army: Publications

Chemical oxidation was evaluated for treatment of a groundwater contaminated with trichloroethylene, acetone, and other organic compounds as measured by the biochemical oxygen demand (BOD) test. Results indicated that maximum contaminant removal was obtained using a combination of hydrogen peroxide, high intensity ultraviolet light, and the addition of tungsten trioxide under acidic conditions.


Verification Techniques Used In Modeling Charleston Harbor, South Carolina, Samuel B. Heltzel Jan 1992

Verification Techniques Used In Modeling Charleston Harbor, South Carolina, Samuel B. Heltzel

United States Army: Publications

Verification to field data provides a means to assess a model's ability to reproduce behavior of the natural system being modeled. Often neither time nor funds are available to collect extensive sets of field data, and alternate techniques are required. This study used the results of a laterally averaged model to provide limited verification for a two-dimensional depthaveraged hydrodynamic and sediment model.

This numerical model investigation used the US Army Corps of Engineers TABS-MD numerical modeling system for open channel flow and sedimentation. Boundary conditions and a verification data set were obtained from the laterally averaged numerical model FIne-Grained Bed …


Properties Of Solidified/Stabilized Chromium Contaminated Soil, Beth C. Fleming, M. John Cullinane, Jr Jan 1992

Properties Of Solidified/Stabilized Chromium Contaminated Soil, Beth C. Fleming, M. John Cullinane, Jr

United States Army: Publications

Solidification/stabilization (S/S) of chromium contaminated soils is influenced by the oxidation state of the chromium. The sum of the hexavalent chromium and trivalent chromium represent the total chromium concentration which is used to determine whether the soil meets the criteria for chromium in the Toxicity Characteristic Leaching Procedure (TCLP) or whether the levels of chromium in applicable extractions are below the drinking water standard. Hexavalent chromium is the more mobile form of chromium and also the more toxic.
Seven vendors and the U.S. Army Engineer Waterways Experiment Station (WES) evaluated SIS treatment of chromium contaminated soils collected from a Superfund …


Flow Impingement Velocities, Snake River, Wyoming, Stephen T. Maynord Jan 1992

Flow Impingement Velocities, Snake River, Wyoming, Stephen T. Maynord

United States Army: Publications

Flow impingement, which occurs when approach channels direct flow into a bank line at large acute angles, results in flow concentration along bank lines, which creates large forces on bank material or bank protection. As part of studies conducted to determine the required riprap size for impinged flow, velocities were measured on the Snake River near Jackson, Wyoming. High velocities and steep water-surface slopes were observed at each impingement site.


Revised Hydraulic Design Of The Los Angeles County Flood Control System, Michael E. Mulvihill, Scott E. Stonestreet Jan 1992

Revised Hydraulic Design Of The Los Angeles County Flood Control System, Michael E. Mulvihill, Scott E. Stonestreet

United States Army: Publications

The US Army Engineer District, Los Angeles, recently completed a study regarding the adequacy of an existing flood control system in Los Angeles County. Results of this study indicate that the level of protection afforded by the system is as low as 25-year in heavily urbanized areas. The Corps of Engineers plans to increase the capacity in two mainstem channels, raising the level of protection to greater than 1OO-year, by constructing parapet walls on top of existing levees and modifying constrictive bridges. A physical model study will be conducted to aid in analysis of complex design problems and will provide …


Levee/Floodwall Freeboard Design For An Urban Flood Control Project, Daniel B. Pridal, Edward F. Sing Jan 1992

Levee/Floodwall Freeboard Design For An Urban Flood Control Project, Daniel B. Pridal, Edward F. Sing

United States Army: Publications

A methodology for the design of levee/floodwall freeboard using evolving guidelines based on the concept of superiority is presented. A case study illustrating the application of the freeboard design guidelines to the Truckee Meadows Project is shown. The Truckee Meadows Project provides a 100 year level of flood protection through the Reno-Sparks, Nevada metropolitan area along an approximate ten mile reach of the Truckee River. Major features of the project include levees, floodwalls, channel modifications, bridge replacement or reconstruction, a detention basin, and drainage improvements. The project is presently in the Preconstruction, Engineering and Design (PED) Phase within the Sacramento …


Removal Of Extremely Low Levels Of Munitions In A Drinking Water Supply, R. Mark Bricka, Wayne Sharp Jan 1992

Removal Of Extremely Low Levels Of Munitions In A Drinking Water Supply, R. Mark Bricka, Wayne Sharp

United States Army: Publications

Past military operations have resulted in the contamination of soils by chemical munitions such as RDX, HMX and TNT (contaminant description, page 2) . The migration of water through the soils can transport the contaminants into groundwater and contaminate drinking water sources . Many military munitions are known or suspected to be carcinogenic and, therefore, must be removed from drinking water .


Analyses Of Special Hazards And Flooding Problems In Tropical Island Environments, Robert C. Macarthur, Douglas L. Hamilton, Michael D. Harvey, Hudson W. Kekaula Jan 1992

Analyses Of Special Hazards And Flooding Problems In Tropical Island Environments, Robert C. Macarthur, Douglas L. Hamilton, Michael D. Harvey, Hudson W. Kekaula

United States Army: Publications

Data and results summarized in this paper show that development of urban projects and design of flood control works in tropical island catchments must consider clear water flooding as well as special hazards such as landslides, flow bulking, high sediment concentrations, mud and debris flows and flow avulsions. The needs for and methods to estimate peak flows, event volumes and the potential extent and depths of flooding during severe storm events in urbanizing tropical environments are described.


Contaminant Groundwater Interception - Rma, S. Paul Miller, William L. Murphy Jan 1992

Contaminant Groundwater Interception - Rma, S. Paul Miller, William L. Murphy

United States Army: Publications

Resolution of groundwater contamination is the major environmental concern at most contamination sites. At some sites immediate control is required to prevent further damage. This paper describes a pioneer groundwater interception and treatment system developed and evaluated at a major Army installation.


Acuta Enews December 1991, Vol. 20, No. 12 Dec 1991

Acuta Enews December 1991, Vol. 20, No. 12

ACUTA Newsletters

In This Issue

10-XXX gives occasion for fraud

President's Message

YaleNET, a variety of services

Think ahead to prevent fraud

MOREnet links 12 campuses

Positions available


Material Handling In A Flexible Manufacturing Systems Processing Part Families, Paul Savory, Gerald Mackulak, Jeff Cochran Dec 1991

Material Handling In A Flexible Manufacturing Systems Processing Part Families, Paul Savory, Gerald Mackulak, Jeff Cochran

Department of Industrial and Management Systems Engineering: Faculty Publications

The objective of this simulation study is to analyze the system performance of a six machine flexible manufacturing system cell in which a material handling system is to be incorporated. The analysis focuses on determining the production potential of the cell by grouping common parts into "families". To accomplish this, computer simulation models are developed using the SIMAN simulation language.

Initially the manufacturing cell is modeled with no material handling system to get an upper bound estimate of production output. We next explore the impact that an automatic guided vehicle (AGV) has on system performance of the manufacturing system cell. …


Acuta Enews November 1991, Vol. 20, No. 11 Nov 1991

Acuta Enews November 1991, Vol. 20, No. 11

ACUTA Newsletters

In This Issue

President's message

Distance learning in Maine

FCC backs phone-line video

Pooling purchasing power

Area code shortage

Positions available


Acuta Enews October 1991, Vol. 20, No. 10 Oct 1991

Acuta Enews October 1991, Vol. 20, No. 10

ACUTA Newsletters

In This Issue

President's message

Wireless alternative to cable

AT&T donates computers

ACUTA budget for 1991-92

Voice messaging is "hit"

Publications Editor profiled


Acuta Enews September 1991, Vol. 20, No. 9 Sep 1991

Acuta Enews September 1991, Vol. 20, No. 9

ACUTA Newsletters

In This Issue

0+ fraud alive and well

AOS rules don't move north

Call screening not mandated

Workshop in Atlanta

Five Ps paying off

Business Manager profile


Acuta Enews August 1991, Vol. 20, No. 8 Aug 1991

Acuta Enews August 1991, Vol. 20, No. 8

ACUTA Newsletters

In This Issue

President's column

Business meeting

Regional meetings

User groups

Director's column

Workshop in Atlanta


Acuta Enews July 1991, Vol. 20, No. 7 Jul 1991

Acuta Enews July 1991, Vol. 20, No. 7

ACUTA Newsletters

In This Issue

ACUTA Forum

Unblocking 1-0-XXX

President's farewell

Affordable fiber to the desk

Value of utility bill audits

$60 million math/science network


Acuta Enews June 1991, Vol. 20, No. 6 Jun 1991

Acuta Enews June 1991, Vol. 20, No. 6

ACUTA Newsletters

In This Issue

Panel to focus on fraud

Interactive video bandwidth

Aggregator requirements

Telex can still be useful

Penn State still pioneering

Positions availabe


Acuta Enews May 1991, Vol. 20, No. 5 May 1991

Acuta Enews May 1991, Vol. 20, No. 5

ACUTA Newsletters

In This Issue

Golf outing set for St. Louis

Network ties islands together

Reorganization at Chicago

Recycling phone books

Party Line

Call for nominations


Acuta Enews April 1991, Vol. 20, No. 4 Apr 1991

Acuta Enews April 1991, Vol. 20, No. 4

ACUTA Newsletters

In This Issue

ACUTA Forum

Travel cards save money

Reorganization at Chicago

Regional Directors elected

Enchancing campus safety

Drew's Knowledge Initiative


Acuta Enews March 1991, Vol. 20, No. 3 Mar 1991

Acuta Enews March 1991, Vol. 20, No. 3

ACUTA Newsletters

In This Issue

Telecom graduate study

Greenville Tech outgrows PBX

World-calling discounts

Call for Presentations

Update on Hawaii

Listing of exhibitors


Acuta Enews February 1991, Vol. 20, No. 2 Feb 1991

Acuta Enews February 1991, Vol. 20, No. 2

ACUTA Newsletters

In This Issue

ACUTA gains new tax status

Stopping a runaway dialer

Just what is an engineer?

FCC ruling awaited

Party Line

In-house accounting