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2012

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Articles 631 - 660 of 1093

Full-Text Articles in Civil and Environmental Engineering

Impacts Of Changes In Land Use And Land Cover On Atmospheric Chemistry And Air Quality Over The 21st Century, S. Wu, L. J. Mickley, J. O. Kaplan, D. J. Jacob Feb 2012

Impacts Of Changes In Land Use And Land Cover On Atmospheric Chemistry And Air Quality Over The 21st Century, S. Wu, L. J. Mickley, J. O. Kaplan, D. J. Jacob

Michigan Tech Publications, Part 1

The effects of future land use and land cover change on the chemical composition of the atmosphere and air quality are largely unknown. To investigate the potential effects associated with future changes in vegetation driven by atmospheric CO 2 concentrations, climate, and anthropogenic land use over the 21st century, we performed a series of model experiments combining a general circulation model with a dynamic global vegetation model and an atmospheric chemical-transport model. Our results indicate that climate-and CO 2-induced changes in vegetation composition and density between 2100 and 2000 could lead to decreases in summer afternoon surface ozone of up …


The Influence Of Boreal Biomass Burning Emissions On The Distribution Of Tropospheric Ozone Over North America And The North Atlantic During 2010, M. Parrington, P. I. Palmer, D. K. Henze, D. W. Tarasick, E. J. Hyer, R. C. Owen, D. Helmig, C. Clerbaux, K. W. Bowman, M. N. Deeter, E. M. Barratt, P. F. Coheur, D. Hurtmans, Z. Jiang, M. George, J. R. Worden Feb 2012

The Influence Of Boreal Biomass Burning Emissions On The Distribution Of Tropospheric Ozone Over North America And The North Atlantic During 2010, M. Parrington, P. I. Palmer, D. K. Henze, D. W. Tarasick, E. J. Hyer, R. C. Owen, D. Helmig, C. Clerbaux, K. W. Bowman, M. N. Deeter, E. M. Barratt, P. F. Coheur, D. Hurtmans, Z. Jiang, M. George, J. R. Worden

Michigan Tech Publications, Part 1

We have analysed the sensitivity of the tropospheric ozone distribution over North America and the North Atlantic to boreal biomass burning emissions during the summer of 2010 using the GEOS-Chem 3-D global tropospheric chemical transport model and observations from in situ and satellite instruments. We show that the model ozone distribution is consistent with observations from the Pico Mountain Observatory in the Azores, ozonesondes across Canada, and the Tropospheric Emission Spectrometer (TES) and Infrared Atmospheric Sounding Instrument (IASI) satellite instruments. Mean biases between the model and observed ozone mixing ratio in the free troposphere were less than 10 ppbv. We …


Customer Relationship Management And Firm Performance: An Empirical Study Of Freight Forwarder Services, Kuo-Chung Shang, Chin-Shan Lu Feb 2012

Customer Relationship Management And Firm Performance: An Empirical Study Of Freight Forwarder Services, Kuo-Chung Shang, Chin-Shan Lu

Journal of Marine Science and Technology–Taiwan

This study empirically identifies customer relationship management (CRM) and examines its impacts on firm performance in the context of freight forwarder services. Using data collected from a survey of 144 freight forwarding firms in Taiwan, a structural equation modeling exercise was conducted to identify crucial CRM dimensions and their influences on the perceived financial performance. Results indicated that CRM dimensions such as customer response and profit interaction are found to have significantly positive effects on the perceived financial performance aspects of profit and growth rate. This research not only investigates crucial CRM but also proposes a model for empirical studies …


The Relationship Between Accelerated Migration Time In Acmt And Ponding Time In Ponding Test For Cement-Based Materials, Yu-Sheng Chen, Ming-Chih Li, Yi-Wen Chan, Chung-Chia Yang Feb 2012

The Relationship Between Accelerated Migration Time In Acmt And Ponding Time In Ponding Test For Cement-Based Materials, Yu-Sheng Chen, Ming-Chih Li, Yi-Wen Chan, Chung-Chia Yang

Journal of Marine Science and Technology–Taiwan

The salt ponding test has been widely used in recent year to evaluate the durability of cement-based materials. However, the duration of more than 90 days salt ponding is considered as time-consuming. In this study, the electrochemical technique (ACMT; Accelerated Chloride Migration Test) is applied to accelerate the movement of chloride ion in the cement-based materials to reduce the duration of testing time. The chloride profiles are obtained from ponding test with various ponding times and ACMT with different accelerated migration times. The total amount of chloride in specimens are calculated from the profiles and compared. Based on the total …


Multiple Scattering Of Sh Waves By An Embedded Truncated Circular Cavity, Deng-How Tsaur, Kao-Hao Chang Feb 2012

Multiple Scattering Of Sh Waves By An Embedded Truncated Circular Cavity, Deng-How Tsaur, Kao-Hao Chang

Journal of Marine Science and Technology–Taiwan

The region-matching technique is implemented to derive a series solution to the SH-wave scattering problem of an embedded truncated circular cavity. An introduced auxiliary boundary partitions the whole analyzed region into two subregions, whose displacement fields are expressed as a superposition of appropriate wavefunctions. Taking advantage of the method of images, the zero-stress boundary condition on the horizontal ground surface is satisfied automatically. Suitable Graf’s addition formulas facilitate the enforcement of boundary conditions on the artificial interface and curved cavity surface for determining the expansion coefficients. Effects of several parameters on steady-state surface motions are discussed. Transient changes in underground …


Ultimate Load-Bearing Capacity Of Self-Anchored Suspension Bridges, Chin-Sheng Kao, Chang-Huan Kou, Wen-Liang Qiu, Jeng-Lin Tsai Feb 2012

Ultimate Load-Bearing Capacity Of Self-Anchored Suspension Bridges, Chin-Sheng Kao, Chang-Huan Kou, Wen-Liang Qiu, Jeng-Lin Tsai

Journal of Marine Science and Technology–Taiwan

This paper presents a method of reduced stiffness coupled with step increments to simulate the nonlinear problem that occurs when a material is in the elasto-plastic stage. A set of equations was developed and used to analyze the ultimate loadbearing capacity and the failure process of a self-anchored suspension bridge. Also investigated here were the effects on the load-bearing capacity due to variations in the strength and stiffness of the four substructures and due to broken hangers. The results showed that variations in the material strength and the structural stiffness of the substructures can lead to different degrees of influence …


Research On Optimization Of Hull Lines For Minimum Resistance Based On Rankine Source Method, Bao-Ji Zhang Feb 2012

Research On Optimization Of Hull Lines For Minimum Resistance Based On Rankine Source Method, Bao-Ji Zhang

Journal of Marine Science and Technology–Taiwan

In order to obtain the hull form with the excellent resistance performance, the optimal design program of hull lines with the independent intellectual property is developed. An optimal design method is proposed based on the minimum total resistance and on NGA, SGA and NLP. The fore-body is optimized with total resistance as the objective function, (in which total resistance can be expressed as sum of wave resistance and friction resistance), with the parameter of hull form modification function as design variables, with an appropriate displacement as a constraint. At last, the numerical optimization examples for s60 ships are provided, which …


Fuzzy Decision On Optimal Collision Avoidance Measures For Ships In Vessel Traffic Service, Chien-Min Su, Ki-Yin Chang, Chih-Yung Cheng Feb 2012

Fuzzy Decision On Optimal Collision Avoidance Measures For Ships In Vessel Traffic Service, Chien-Min Su, Ki-Yin Chang, Chih-Yung Cheng

Journal of Marine Science and Technology–Taiwan

This article proposes a new collision avoidance decision method for ships, allowing ships at risk of collision to take timely collision avoidance measures to ensure safe passage. Through vessel traffic service (VTS) collision alert system, an analysis can be made for the probability of a ship collision and an early warning can be issued. For ships in potential collision danger, the proposed method will use Microsoft Visual Studio to establish a knowledge base of international regulations for preventing collisions at sea. Thus, based on an analysis of the situation when encountering other ships, the knowledge base will suggest an appropriate …


Papaya (Carica Papaya) Seed As A Low-Cost Sorbent For Zinc Removal, Siew-Teng Ong, Shiau-Ping Yip, Pei-Sin Keng, Siew-Ling Lee, Yung-Tse Hung Feb 2012

Papaya (Carica Papaya) Seed As A Low-Cost Sorbent For Zinc Removal, Siew-Teng Ong, Shiau-Ping Yip, Pei-Sin Keng, Siew-Ling Lee, Yung-Tse Hung

Civil and Environmental Engineering Faculty Publications

The potential of using papaya seed as a sorbent for the removal of Zn from aqueous solution was investigated. The sorption characteristics of the sorbent was studied under various experimental conditions, such as pH, contact time, concentration of Zn(II), agitation rate and sorbent’s particle size. The equilibrium data have been studied using Langmuir, Freundlich and Brunauer-Emmett-Teller equations. The best correlation was obtained using Langmuir isotherm with the regression coefficient value of 0.9799 and maximum sorption capacity of 19.88 mg/g. The effective pH for the maximum uptake of Zn(II) was at pH 5.0. An increase in percentage uptake of Zn(II) can …


Steel Building Assessment In Post-Earthquake Fire Environments With Fiber Optical Sensors, Genda Chen, Ying Huang, Hai Xiao Feb 2012

Steel Building Assessment In Post-Earthquake Fire Environments With Fiber Optical Sensors, Genda Chen, Ying Huang, Hai Xiao

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.


Phase I Development Of An Aesthetic, Precast Concrete Bridge Rail, Scott Rosenbaugh, Ronald K. Faller, Robert W. Bielenberg, Dean L. Sicking, John D. Reid Feb 2012

Phase I Development Of An Aesthetic, Precast Concrete Bridge Rail, Scott Rosenbaugh, Ronald K. Faller, Robert W. Bielenberg, Dean L. Sicking, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.


The Bridge Newsletter Spring 2012, Missouri University Of Science And Technology Feb 2012

The Bridge Newsletter Spring 2012, Missouri University Of Science And Technology

The Bridge Newsletter

-Light-weight foam could cushion expensive bridge repairs
-New Chancellor
-The house of the future today
-High-tech approach to project management


Strength And Fatigue Of Three Glass Fiber Reinforced Composite Bridge Decks With Mechanical Deck To Stringer Connections, Andrew Gleason, Peter Dusicka Feb 2012

Strength And Fatigue Of Three Glass Fiber Reinforced Composite Bridge Decks With Mechanical Deck To Stringer Connections, Andrew Gleason, Peter Dusicka

Civil and Environmental Engineering Faculty Publications and Presentations

Replacement of the steel grating deck on the lift span of the Morrison Bridge in Portland, OR, will utilize glass fiber reinforced polymer (FRP) panels to address ongoing maintenance issues of the deteriorated existing deck, improve driver safety and introduce bridge water runoff treatment. This report outlines the testing methods and results of an experimental program aimed primarily at evaluating a new open cell deck. While most FRP panels are connected via shear studs that are grouted within isolated pockets, the panels in this case were bolted directly to the steel stringers. Two different FRP deck options were evaluated for …


Railroad Subgrade Support And Performance Indicators: A Review Of Available Laboratory And In-Situ Testing Methods, Michael T. Mchenry, Jerry G. Rose Feb 2012

Railroad Subgrade Support And Performance Indicators: A Review Of Available Laboratory And In-Situ Testing Methods, Michael T. Mchenry, Jerry G. Rose

Kentucky Transportation Center Research Report

The quality and support of the subgrade portion of a railroad trackbed are vital to the overall performance of the track structure. The subgrade is an integral component of the track structure and its performance properties must be considered in order to effectively assess its influence on subsequent track quality. European and Asian railways are particularly advanced in implementing subgrade performance indicators into their track designs and assessments. As train speed and tonnage increase in the U.S., the evaluation and influence of subgrade performance will become even more paramount. There are numerous means of measuring and predicting subgrade performance. Both …


Micromechanical Study Of Two-Phase Flow During Air Sparging, Shengyan Gao Jan 2012

Micromechanical Study Of Two-Phase Flow During Air Sparging, Shengyan Gao

Dissertations

Air sparging (AS) is an in-situ soil/groundwater remediation technology, which involves the injection of pressurized air/oxygen through an air sparging well below the region of contamination. The efficiency of the in-situ sparging system is mainly controlled by the extent of contact between injected air and contaminated soil and pore fluid. Hence, characterizing the mechanisms governing movement of air through saturated porous media is therefore critical to the design of an effective cleanup treatment. However, in spite of the success of air sparging as a remediation technique for the clean-up of contaminated soils, to date, the fundamental mechanisms or the physics …


Development Of Gis Database For Hayward Fault, Olugbope Maku Jan 2012

Development Of Gis Database For Hayward Fault, Olugbope Maku

Theses

Earthquake activity and its attendant effects on the earth surface have been a major concern for some time now, especially considering their negative effects in loss of human life, property damage including the emotional impact on witnesses. This study focuses on the Hayward Fault, located in the heart of population center in Contra Costa County of the San Francisco Bay Area, California.

Geographical Information System (GIS) has proved to be a valuable tool in recent years in the study and analysis of earthquakes to complement emergency response efforts. GIS has been adapted to estimate the impact of the geologic hazards …


Slides: Unconventional Gas And Oil – Potential Air Emissions, John Imse Jan 2012

Slides: Unconventional Gas And Oil – Potential Air Emissions, John Imse

Air Quality Impacts from Oil and Gas Development (January 27)

Presenter: John Imse, Hydrogeologist, ENVIRON International Corporation presents an overview of the current methods for developing a shale play and the typical site operations

10 slides


Slides: Air Monitoring And Litigation Update, John Jacus Jan 2012

Slides: Air Monitoring And Litigation Update, John Jacus

Air Quality Impacts from Oil and Gas Development (January 27)

Presenter: John Jacus, Partner, Davis Graham & Stubbs LLP, reviews recent litigation aimed at oil and gas development activities with respect to air emissions impacts, and also several recent and ongoing studies and ambient monitoring efforts focused upon air emissions from oil and gas activities

23 slides


Slides: Air Quality - Oil And Gas Development, Paul R. Tourangeau Jan 2012

Slides: Air Quality - Oil And Gas Development, Paul R. Tourangeau

Air Quality Impacts from Oil and Gas Development (January 27)

Presenter: Paul Tourangeau, Assistant General Counsel, DCP Midstream, LP and former Director, Colorado Air Pollution Control Division, addresses regulatory requirements and policies related to air emissions from the oil and gas sector, including recent and current initiatives at the state and federal level

8 slides


Slides: Hydrofracking: Air Issues And Community Exposure, Debra A. Kaden Jan 2012

Slides: Hydrofracking: Air Issues And Community Exposure, Debra A. Kaden

Air Quality Impacts from Oil and Gas Development (January 27)

Presenter: Debra Kaden, Ph.D., Toxicologist, ENVIRON International Corporation, discusses air concentrations of chemicals of potential health concern surrounding oil and gas development activities, as well as temporal and spatial patterns of these chemicals in the ambient environment. Such information is necessary to evaluate possible health impacts of the drilling process on air in surrounding communities.

19 slides


Agenda: Air Quality Impacts From Oil And Gas Development, University Of Colorado Boulder. Natural Resources Law Center Jan 2012

Agenda: Air Quality Impacts From Oil And Gas Development, University Of Colorado Boulder. Natural Resources Law Center

Air Quality Impacts from Oil and Gas Development (January 27)

Oil and gas development and hydraulic fracturing have received enormous attention over the past few years, and most of that attention has focused on the potential impacts of such development on water quality. However, the potential impacts on air quality from oil and gas development have received far less public and media attention and discussion. This two-hour program will assess the current scientific knowledge, regulatory requirements and policies regarding the impacts on air quality from oil and gas development and will address current initiatives at the state and national levels to further regulate and control those impacts.


Estimation Of Performance Indices For The Planning Of Sustainable Transportation Systems, Pankaj Maheshwari, Alexander Paz, Pushkin Kachroo Jan 2012

Estimation Of Performance Indices For The Planning Of Sustainable Transportation Systems, Pankaj Maheshwari, Alexander Paz, Pushkin Kachroo

Graduate Publications & Presentations

What is sustainable transportation system?

Fulfill the needs of current generations without compromising the ability of future generations

Utilize resources without compromising their health and productivity Leads to development that improves quality of life

Assimilate economic, ecological, social, and bio-physical components of resource ecosystems

Minimize the use of renewable and non-renewable resources, provide affordability and equity between generations


A Global Assessment Of The Water Footprint Of Farm Animal Products, Mesfin Mekonnen, Arjen Y. Hoekstra Jan 2012

A Global Assessment Of The Water Footprint Of Farm Animal Products, Mesfin Mekonnen, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

The increase in the consumption of animal products is likely to put further pressure on the world’s freshwater resources. This paper provides a comprehensive account of the water footprint of animal products, considering different production systems and feed composition per animal type and country. Nearly one-third of the total water footprint of agriculture in the world is related to the production of animal products. The water footprint of any animal product is larger than the water footprint of crop products with equivalent nutritional value. The average water footprint per calorie for beef is 20 times larger than for cereals and …


Canopy Radiation Transmission For An Energy Balance Snowmelt Model, Vinod Mahat, David G. Tarboton Jan 2012

Canopy Radiation Transmission For An Energy Balance Snowmelt Model, Vinod Mahat, David G. Tarboton

Civil and Environmental Engineering Faculty Publications

To better estimate the radiation energy within and beneath the forest canopy for energy balance snowmelt models, a two stream radiation transfer model that explicitly accounts for canopy scattering, absorption and reflection was developed. Upward and downward radiation streams represented by two differential equations using a single path assumption were solved analytically to approximate the radiation transmitted through or reflected by the canopy with multiple scattering. This approximation results in an exponential decrease of radiation intensity with canopy depth, similar to Beer's law for a deep canopy. The solution for a finite canopy is obtained by applying recursive superposition of …


Modeling Groundwater Levels On The Calera Aquifer Region In Central Mexico Using Modflow, Jairo E. Hernández, Prasanna H. Gowda, Terry A. Howell, Jean L. Steiner, Francisco Mojarro, Ernesto P. Núñez, José R. Avila Jan 2012

Modeling Groundwater Levels On The Calera Aquifer Region In Central Mexico Using Modflow, Jairo E. Hernández, Prasanna H. Gowda, Terry A. Howell, Jean L. Steiner, Francisco Mojarro, Ernesto P. Núñez, José R. Avila

Civil Engineering Faculty Publications and Presentations

A conceptual model for the Calera Aquifer has been created to represent the aquifer system beneath the Calera Aquifer Region (CAR) in the State of Zacatecas, Mexico. The CAR area was uniformly partitioned into a 500 X 500 m grid generating a high resolution model that represented the natural boundaries of the aquifer. A computer model was calibrated and validated to verify output from the model corresponding to situations that matched the historical aquifer performance. Predicted groundwater levels were compared with measured data collected from nine observation wells between 1954 and 2004 to evaluate model performance. The main objective of …


Slides: Natural Gas: Game Changer Or Runner Left On Base? Working To Get It Right In Co!, Gary Graham Jan 2012

Slides: Natural Gas: Game Changer Or Runner Left On Base? Working To Get It Right In Co!, Gary Graham

Drawing the Blueprint for a Sustainable Natural Gas Future (January 18)

Presenter: Dr. Gary Graham, Director, Lands Program, Western Resource Advocates

21 slides


Slides: Drawing The Blueprint For A Sustainable Natural Gas Future, Mark K. Boling Jan 2012

Slides: Drawing The Blueprint For A Sustainable Natural Gas Future, Mark K. Boling

Drawing the Blueprint for a Sustainable Natural Gas Future (January 18)

Presenter: Mark. K. Boling, Executive Vice-President and General Counsel, Southwestern Energy

23 slides


Slides: Current And Proposed Research Activities Addressing Health, Environmental, Economic, And Political Issues Related To Natural Gas Development, University Of Colorado. School Of Public Health. Department Of Environmental And Occupational Health Jan 2012

Slides: Current And Proposed Research Activities Addressing Health, Environmental, Economic, And Political Issues Related To Natural Gas Development, University Of Colorado. School Of Public Health. Department Of Environmental And Occupational Health

Drawing the Blueprint for a Sustainable Natural Gas Future (January 18)

Presenter: Department of Environmental and Occupational Health, University of Colorado School of Public Health

20 slides


Agenda: Drawing The Blueprint For A Sustainable Natural Gas Future, University Of Colorado At Denver. Wirth Chair In Environmental And Community Development Policy, University Of Colorado Boulder. Natural Resources Law Center. Intermountain Oil And Gas Bmp Project Jan 2012

Agenda: Drawing The Blueprint For A Sustainable Natural Gas Future, University Of Colorado At Denver. Wirth Chair In Environmental And Community Development Policy, University Of Colorado Boulder. Natural Resources Law Center. Intermountain Oil And Gas Bmp Project

Drawing the Blueprint for a Sustainable Natural Gas Future (January 18)

A stakeholder-led forum discussing the key topics affecting natural gas as a safe and sustainable energy resource. Participants learned about the current research and related resources at Colorado’s three research universities and participated in designing future research needs.


Lynches Lane Reed & Willow Bed Facility Final Report South Dubin County Council, Liam Mccarton, Sean O'Hogain, Don Mcdonald, Anna Reid Jan 2012

Lynches Lane Reed & Willow Bed Facility Final Report South Dubin County Council, Liam Mccarton, Sean O'Hogain, Don Mcdonald, Anna Reid

Reports

This final report will present results from a two year study to monitor the performance of a hybrid reed willow bed facility at Lynches Lane, in the administrative area of South Dublin County Council (SDCC). Design specifications for the facility are presented. Monitoring results for a two year period including influent and effluent parameters, rainfall, potential evapotranspiration, and soil classification are also presented and discussed. During the two year monitoring period the system achieved a zero discharge. This report will discuss the potential application of similar systems within South Dublin County Council administrative area. This is in the context of …