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Change Orders And Lessons Learned, Paul Goodrum, Timothy R. B. Taylor, William Lester, Alex McCoy, Mohammed M. Uddin, Yongwei Shan 2010 University of Kentucky

Change Orders And Lessons Learned, Paul Goodrum, Timothy R. B. Taylor, William Lester, Alex Mccoy, Mohammed M. Uddin, Yongwei Shan

Kentucky Transportation Center Research Report

Many times, change is necessary for the success of a project. “Change, defined as any event that results in a modification of the original scope, execution time, or cost of work, happens on most projects due to the uniqueness of each project and the limited resources of time and money available for planning” (Hanna, Camlic, Peterson,& Nordheim, 2002). While change orders are necessary to address unforeseen conditions and other unavoidable or unanticipated occurrences, they tend to negatively affect construction. In most public works, change orders are the main reason for construction delays and cost overruns (Wu, Hsieh, & Cheng, 2005). Change ...


Hydrodynamic Modeling Of San Elijo Lagoon, California, Mary Elizabeth nee Friedmann Bourgoyne 2010 Louisiana State University and Agricultural and Mechanical College

Hydrodynamic Modeling Of San Elijo Lagoon, California, Mary Elizabeth Nee Friedmann Bourgoyne

LSU Master's Theses

Decisions on where to concentrate management efforts need to be guided by an ability to accurately simulate and predict physical and ecological changes. Many restoration projects experience difficulties due to a lack of understanding of the ecological response and evolution of wetland systems (Goodwin et al., 2001). There are several approaches that can be taken in analyzing a system. The appropriate selection should be based on the available data, the spatial scale of the wetland, and the physical processes governing the system (Goodwin and Kamman, 2001). Predictive tools are essential for good long-term management (Goodwin et al., 2001). The objective ...


Experimental Study On Single Cement Fracture Exposed To Co2 Saturated Brine Under Dynamic Conditions, Tevfik Yalcinkaya 2010 Louisiana State University and Agricultural and Mechanical College

Experimental Study On Single Cement Fracture Exposed To Co2 Saturated Brine Under Dynamic Conditions, Tevfik Yalcinkaya

LSU Master's Theses

Carbon capture and storage is one of the technologies that could help reduce CO2 concentration in the atmosphere while contributing to cutback of Greenhouse Gas emissions. Depleted oil and gas fields are favorable targets for CO2 storage because existing wells can be readily used as injection wells. However, a number of abandoned wells also serve as gateway to the reservoir which should be considered in the context of effective Carbon capture and storage. Wellbore cement is a very essential element in wellbore systems that serve as a barrier between different zones in the subsurface. The fractures inside wellbore cement sheath ...


Effect Of Management Awareness Of Safety Climate Concept On Organizational Safety Climate, Christopher Michael Holzner 2010 Louisiana State University and Agricultural and Mechanical College

Effect Of Management Awareness Of Safety Climate Concept On Organizational Safety Climate, Christopher Michael Holzner

LSU Master's Theses

Safety research and practice have shifted focus away from accident rates and accident causal information to a more proactive approach that may predict organizational safety trends. This proactive approach involves the concept of an organizational safety culture and the use of surveys to measure organizational safety climate or „snapshot‟ of the organizational safety culture. Surveys were administered to line workers, supervisors, and managers at a modular home manufacturing company before and after safety climate information was presented to supervisors and managers in an attempt to measure the effect of the supervisors‟ and managers‟ increased awareness of the factors that define ...


Net Radiation Dynamics: Performance Of 20 Daily Net Radiation Models As Related To Model Structure And Intricacy In Two Climates, Suat Irmak, Denis Mutiibwa, José O. Payero 2010 University of Nebraska-Lincoln

Net Radiation Dynamics: Performance Of 20 Daily Net Radiation Models As Related To Model Structure And Intricacy In Two Climates, Suat Irmak, Denis Mutiibwa, José O. Payero

Biological Systems Engineering: Papers and Publications

We compared daily net radiation (Rn) estimates from 19 methods with the ASCE‐EWRI Rn estimates in two climates: Clay Center, Nebraska (sub‐humid) and Davis, California (semi‐arid) for the calendar year. The performances of all 20 methods, including the ASCE‐EWRI Rn method, were then evaluated against Rn data measured over a non‐stressed maize canopy during two growing seasons in 2005 and 2006 at Clay Center. Methods differ in terms of inputs, structure, and equation intricacy. Most methods differ in estimating the cloudiness factor, emissivity (α), and calculating net longwave radiation (Rnl ...


Numerically Predicting Seepage Gradient Forces And Erosion: Sensitivity To Soil Hydraulic Properties, Garey A. Fox, Derek M. Heeren, Glenn V. Wilson, E. J. Langendoen, Amanda K. Fox, Maria L. Chu-Agor 2010 Oklahoma State University - Main Campus

Numerically Predicting Seepage Gradient Forces And Erosion: Sensitivity To Soil Hydraulic Properties, Garey A. Fox, Derek M. Heeren, Glenn V. Wilson, E. J. Langendoen, Amanda K. Fox, Maria L. Chu-Agor

Biological Systems Engineering: Papers and Publications

Research has suggested that streambank seepage can be an important mechanism of bank instability; however, limited information is available on the level of soil characterization necessary to accurately predict seepage gradient forces and erosion. The objective of this research was to quantify the expected range of predicted seepage gradients for various degrees of site characterization. Uncertainty analysis on seepage gradient predictions was performed relative to variability in soil hydraulic properties. A two-dimensional unsaturated/saturated groundwater flow model was used to simulate a homogeneous soil layer for sand and loamy sand soils packed at various bulk densities, ρb. A pedotransfer ...


Opto-Electrophoretic Detection Of Bio-Molecules Using Conducting Chalcogenide Glass Sensors, Zhiyong Yang, Megan K. Fah, Kelly A. Reynolds, Jonathan D. Sexton, Mark R. Riley, Marie-Laure Anne, Bruno Bureau, Pierre Lucas 2010 University of Arizona

Opto-Electrophoretic Detection Of Bio-Molecules Using Conducting Chalcogenide Glass Sensors, Zhiyong Yang, Megan K. Fah, Kelly A. Reynolds, Jonathan D. Sexton, Mark R. Riley, Marie-Laure Anne, Bruno Bureau, Pierre Lucas

Biological Systems Engineering: Papers and Publications

Novel telluride glasses with high electrical conductivity, wide infrared transparency and good resistance to crystallization are used to design an opto-electrophoretic sensor for detection and identification of hazardous microorganisms. The sensor is based on an attenuated total reflectance element made of Ge-As-Te glass that serves as both an optical sensing zone and an electrode for driving the migration of bio-molecules within the evanescent wave of the sensor. An electric field is applied between the optical element and a counter electrode in order to induce the migration of bio-molecules carrying surface charges. The effect of concentration and applied voltage is tested ...


On The Dynamics Of Canopy Resistance: Generalized Linear Estimation And Relationships With Primary Micrometeorological Variables, Suat Irmak, Denis Mutiibwa 2010 University of Nebraska-Lincoln

On The Dynamics Of Canopy Resistance: Generalized Linear Estimation And Relationships With Primary Micrometeorological Variables, Suat Irmak, Denis Mutiibwa

Biological Systems Engineering: Papers and Publications

The 1‐D and single layer combination‐based energy balance Penman‐Monteith (PM) model has limitations in practical application due to the lack of canopy resistance (rc) data for different vegetation surfaces. rc could be estimated by inversion of the PM model if the actual evapotranspiration (ETa) rate is known, but this approach has its own set of issues. Instead, an empirical method of estimating rc is suggested in this study. We investigated the relationships between primary micrometeorological parameters and rc and developed seven models to estimate rc for a nonstressed maize canopy on an ...


Surfactant-Induced Flow Behavior Effects In Gas Condensate Reservoirs, Bikash Deep. Saikia 2010 Louisiana State University and Agricultural and Mechanical College

Surfactant-Induced Flow Behavior Effects In Gas Condensate Reservoirs, Bikash Deep. Saikia

LSU Master's Theses

Natural gas, which accounts for a quarter of world’s energy, has been a major energy source because of its abundance and less impact on environment. With explorations at higher depth, pressure and temperature, the share of gas condensate reservoirs to global gas production is increasing. A unique production challenge associated with these reservoirs is the condensate blockage problem, which is the buildup of condensate liquid saturation around wellbore as a result of drawdown below dew point pressure. Mitigation of this problem requires in depth understanding of the multiphase flow of liquid and gas. Surfactants are well known in the ...


An Operational Policy For A Single Vendor Multi Buyer Integrated Inventory Supply Chain System Considering Shipping Time, Chiranjit Saha 2010 Louisiana State University and Agricultural and Mechanical College

An Operational Policy For A Single Vendor Multi Buyer Integrated Inventory Supply Chain System Considering Shipping Time, Chiranjit Saha

LSU Master's Theses

Since its introduction, the concept of integrated inventory supply chain has received a considerable amount of attention. The majority of studies in the last three decades revealed an increase in holding cost as product moves further down the chain or up the chain. A recent study Hoque (2008) considered vendor’s setup cost and inventory holding cost. Some research also considered fixed transportation cost, which is unrealistic. This study focuses on a single-vendor, multi-buyer scenario and presents three models. First, two models illustrate the transferring of equally-sized batches. Then, a third model considers the transferring of unequally-sized batches in a ...


Nonlinear Circuit Analysis Via Perturbation Methods And Hardware Prototyping, Kofi Odame, P. E. Hasler 2010 Dartmouth College

Nonlinear Circuit Analysis Via Perturbation Methods And Hardware Prototyping, Kofi Odame, P. E. Hasler

Open Dartmouth: Peer-reviewed articles by Dartmouth faculty

Nonlinear signal processing is necessary in many emerging applications where form factor and power are at a premium. In order to make such complex computation feasible under these constraints, it is necessary to implement the signal processors as analog circuits. Since analog circuit design is largely based on a linear systems perspective, new tools are being introduced to circuit designers that allow them to understand and exploit circuit nonlinearity for useful processing. This paper discusses two such tools, which represent nonlinear circuit behavior in a graphical way, making it easy to develop a qualitative appreciation for the circuits under study.


The Effects Of Lean On Employees' Affective Attitude In A Modular Homebuilding Manufacturer, Digvesh Khot 2010 Louisiana State University and Agricultural and Mechanical College

The Effects Of Lean On Employees' Affective Attitude In A Modular Homebuilding Manufacturer, Digvesh Khot

LSU Master's Theses

Many organizational problems are related to job dissatisfaction, job-related stress, and lack of commitment in workers. Employees’ Affective Attitude (EAA) involves these three factors: job satisfaction, job stress, and commitment. This research is aimed at measuring the impact of Lean concepts on EAA factors. While providing an overview of Lean production and construction, this study focuses on one fundamental Lean concept, Kaizen. This thesis describes a case study showcasing the application of Lean concepts through Kaizen events and its impact on EAA for a modular homebuilder company. Based on previous literature a conceptual model was developed describing the potential links ...


Empirically Evaluating And Developing Alarm Rate Standards For Liquid Pipeline Control Room Operators, Glen David Uhack II 2010 Louisiana State University and Agricultural and Mechanical College

Empirically Evaluating And Developing Alarm Rate Standards For Liquid Pipeline Control Room Operators, Glen David Uhack Ii

LSU Master's Theses

The liquid and gas pipeline community has recently been faced with the challenge of new governmental regulations set forth by congress which are being implemented by PHMSA (an arm of the DOT). These new governmental regulations need to understand the role of the human in the loop as part of alarm management systems. To investigate alarm rate standards a repeated measures design was developed that included a series of ten (10) simulated liquid pipeline operator scenarios utilizing high fidelity liquid pipeline simulation software (Stoner Pipeline Simulator). A total of 39 participants volunteered for this study. Participants completed two subsets of ...


Solid-Liquid Separation Technologies In The Conversion Of Bagasse To Liquid Fuel, Keith Miller 2010 Louisiana State University and Agricultural and Mechanical College

Solid-Liquid Separation Technologies In The Conversion Of Bagasse To Liquid Fuel, Keith Miller

LSU Master's Theses

Development of liquid biofuels has entered a new phase of large scale pilot demonstrations. A number of plants in operation or under construction face the engineering challenges of creating a viable plant design, scaling up, and optimizing various unit operations. It is well-known that separation technologies account for 50-70% of both capital and operating costs. Processes vary in terms of selection of unit operations; however, solid-liquid separations are likely to be a major contributor to the overall project costs. A typical process for ethanol production from biomass includes several solid-liquid separation steps. The nature of biomass derived materials makes it ...


Identifying A Computer Forensics Expert: A Study To Measure The Characteristics Of Forensic Computer Examiners, Gregory H. Carlton, Reginald Worthley 2010 California State Polytechnic University

Identifying A Computer Forensics Expert: A Study To Measure The Characteristics Of Forensic Computer Examiners, Gregory H. Carlton, Reginald Worthley

Journal of Digital Forensics, Security and Law

The usage of digital evidence from electronic devices has been rapidly expanding within litigation, and along with this increased usage, the reliance upon forensic computer examiners to acquire, analyze, and report upon this evidence is also rapidly growing. This growing demand for forensic computer examiners raises questions concerning the selection of individuals qualified to perform this work. While courts have mechanisms for qualifying witnesses that provide testimony based on scientific data, such as digital data, the qualifying criteria covers a wide variety of characteristics including, education, experience, training, professional certifications, or other special skills. In this study, we compare task ...


Adaptation Of Pyflag To Efficient Analysis Of Seized Computer Data Storage, Aleksander Byrski, Wojciech Stryjewski, Bartłomiej Czechowicz 2010 AGH University of Science and Technology

Adaptation Of Pyflag To Efficient Analysis Of Seized Computer Data Storage, Aleksander Byrski, Wojciech Stryjewski, Bartłomiej Czechowicz

Journal of Digital Forensics, Security and Law

Based on existing software aimed at investigation support in the analysis of computer data storage seized during investigation (PyFlag), an extension is proposed involving the introduction of dedicated components for data identification and filtering. Hash codes for popular software contained in NIST/NSRL database are considered in order to avoid unwanted files while searching and to classify them into several categories. The extension allows for further analysis, e.g. using artificial intelligence methods. The considerations are illustrated by the overview of the system's design.


Clustering Spam Domains And Destination Websites: Digital Forensics With Data Mining, Chun Wei, Alan Sprague, Gary Warner, Anthony Skjellum 2010 University of Alabama, Birmingham

Clustering Spam Domains And Destination Websites: Digital Forensics With Data Mining, Chun Wei, Alan Sprague, Gary Warner, Anthony Skjellum

Journal of Digital Forensics, Security and Law

Spam related cyber crimes have become a serious threat to society. Current spam research mainly aims to detect spam more effectively. We believe the identification and disruption of the supporting infrastructure used by spammers is a more effective way of stopping spam than filtering. The termination of spam hosts will greatly reduce the profit a spammer can generate and thwart his ability to send more spam. This research proposes an algorithm for clustering spam domains extracted from spam emails based on the hosting IP addresses and tracing the IP addresses over a period of time. The results show that many ...


Computer Forensic Functions Testing: Media Preparation, Write Protection And Verification, Yinghua Guo, Jill Slay 2010 University of South Australia

Computer Forensic Functions Testing: Media Preparation, Write Protection And Verification, Yinghua Guo, Jill Slay

Journal of Digital Forensics, Security and Law

The growth in the computer forensic field has created a demand for new software (or increased functionality to existing software) and a means to verify that this software is truly forensic i.e. capable of meeting the requirements of the trier of fact. In this work, we review our previous work---a function oriented testing framework for validation and verification of computer forensic tools. This framework consists of three parts: function mapping, requirements specification and reference set development. Through function mapping, we give a scientific and systemized description of the fundamentals of computer forensic discipline, i.e. what functions are needed ...


Developing Voip Honeypots: A Preliminary Investigation Into Malfeasant Activity, Craig Valli 2010 Edith Cowan University

Developing Voip Honeypots: A Preliminary Investigation Into Malfeasant Activity, Craig Valli

Journal of Digital Forensics, Security and Law

30 years ago PABX systems were compromised by hackers wanting to make long distance calls at some other entities expense. This activity faded as telephony became cheaper and PABX systems had countermeasures installed to overcome attacks. Now the world has moved onto the provision of telephony via broadband enabled Voice over Internet Protocol (VoIP) with this service now being provided as a replacement for conventional fixed wire telephony by major telecommunication providers worldwide. Due to increasing bandwidth it is possible for systems to support multiple voice connections simultaneously. The networked nature of the Internet allows for attackers of these VoIP ...


Higate (High Grade Anti-Tamper Equipment) Prototype And Application To E-Discovery, Yui Sakurai, Yuki Ashino, Tetsutaro Uehara, Hiroshi Yoshiura, Ryoichi Sasaki 2010 Tokyo Denki University

Higate (High Grade Anti-Tamper Equipment) Prototype And Application To E-Discovery, Yui Sakurai, Yuki Ashino, Tetsutaro Uehara, Hiroshi Yoshiura, Ryoichi Sasaki

Journal of Digital Forensics, Security and Law

These days, most data is digitized and processed in various ways by computers. In the past, computer owners were free to process data as desired and to observe the inputted data as well as the interim results. However, the unrestricted processing of data and accessing of interim results even by computer users is associated with an increasing number of adverse events. These adverse events often occur when sensitive data such as personal or confidential business information must be handled by two or more parties, such as in the case of e-Discovery, used in legal proceedings, or epidemiologic studies. To solve ...


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