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2013

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Articles 61 - 90 of 7289

Full-Text Articles in Engineering

Predicting Voltage Abnormality Using Power System Dynamics, Nagendrakumar Beeravolu Dec 2013

Predicting Voltage Abnormality Using Power System Dynamics, Nagendrakumar Beeravolu

LSU New Orleans Theses and Dissertations

The purpose of this dissertation is to analyze dynamic behavior of a stressed power system and to correlate the dynamic responses to a near future system voltage abnormality. It is postulated that the dynamic response of a stressed power system in a short period of time-in seconds-contains sufficient information that will allow prediction of voltage abnormality in future time-in minutes. The PSSE dynamics simulator is used to study the dynamics of the IEEE 39 Bus equivalent test system. To correlate dynamic behavior to system voltage abnormality, this research utilizes two different pattern recognition methods one being algorithmic method known as …


Rocket Motor Diagnostics Using Tunable Diode Laser Spectroscopy For Chemically Non-Reacting Air/Water Vapor Mixture In Internal Flow, Wesley Carleton Dec 2013

Rocket Motor Diagnostics Using Tunable Diode Laser Spectroscopy For Chemically Non-Reacting Air/Water Vapor Mixture In Internal Flow, Wesley Carleton

LSU New Orleans Theses and Dissertations

This research is for the implementation of non-intrusive measurement techniques in the study of high temperature pipe flow. A low pressure, laboratory scale hybrid rocket motor simulator was built to achieve high temperatures with various gases. A quartz test section was designed, built, and implemented into the existing test setup to accommodate the laser beam of the existing Tunable Diode Laser Absorption Spectrometer (TDLAS) system which was designed to observe water vapor. A super-heated water vapor injector was designed to obtain the desired water vapor concentrations. Flow characteristics were simultaneously recorded using the existing TDLAS system and the DAQ system …


Beluga Whale Vocalizations, Michael T. Johnson Dec 2013

Beluga Whale Vocalizations, Michael T. Johnson

Dr. Dolittle Project: A Framework for Classification and Understanding of Animal Vocalizations

Sound files:

A Chirp; A Whistle ; B Chirp; B Whistle: Buzz; C Whistle; CH6 A Chirp; D Whistle; Down Warble; Down Whistle; E Whistle; Voca


Sensible Heat Balance And Heat-Pulse Method Applicability To In Situ Soil-Water Evaporation, Andrew C. Trautz, Kathleen M. Smits, Paul Schulte, Tissa H. Illangasekare Dec 2013

Sensible Heat Balance And Heat-Pulse Method Applicability To In Situ Soil-Water Evaporation, Andrew C. Trautz, Kathleen M. Smits, Paul Schulte, Tissa H. Illangasekare

Civil Engineering Faculty Publications - Archive

A combined heat-pulse and sensible heat balance method can be used to determine evaporation using temperature measurements and thermal property estimations. The objective of this study was to investigate the applicability of the combined heat-pulse and sensible heat balance method by comparing laboratory experimental data to both an analytical and a multiphase heat and mass transfer model. A bench-scale laboratory experiment was performed to measure soil thermal and hydraulic properties at fine spatial and temporal resolutions. Comparisons of experimental and numerical results confirmed the applicability of the heat-pulse and sensible heat balance methods to determine evaporation rates. Results showed close …


Network Interdependency Modeling For Risk Assessment On Built Infrastructure Systems, Vhance V. Valencia Dec 2013

Network Interdependency Modeling For Risk Assessment On Built Infrastructure Systems, Vhance V. Valencia

Theses and Dissertations

As modern infrastructures become more interconnected, the decision-making process becomes more difficult because of the increased complexity resulting from infrastructure interdependencies. Simulation and network modeling provide a way to understand system behavior as a result of interdependencies. One area within the asset management literature that is not well covered is infrastructure system decay and risks associated with that decay. This research presents an enhanced version of Haimes' input-output inoperability model (IIM) in the analysis of built infrastructure systems. Previous applications of the IIM characterized infrastructure at the national level utilizing large economic databases. This study develops a three-phased approach that …


Temperature-Dependent Dielectric And Thermal Properties Of Whey Protein Gel And Mashed Potato, Jiajia Chen, Krishnamoorthy Pitchai, Sohan Birla, Ricardo Gonzalez, David Jones, Jeyamkondan Subbiah Dec 2013

Temperature-Dependent Dielectric And Thermal Properties Of Whey Protein Gel And Mashed Potato, Jiajia Chen, Krishnamoorthy Pitchai, Sohan Birla, Ricardo Gonzalez, David Jones, Jeyamkondan Subbiah

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Temperature-dependent dielectric properties (dielectric constant and dielectric loss factor) and thermal properties (thermal conductivity and specific heat capacity) of whey protein gel and mashed potato were measured from -20°C to 100°C. A dielectric properties measurement system and a multipoint temperature calibration protocol were developed. The system consists of an impedance analyzer, a high-temperature coaxial cable, a high-temperature coaxial probe, a micro-climatic chamber and a metal sample holder. Calibrations at two temperatures (25°C and 85°C) were sufficient to accurately measure the dielectric properties of foods from frozen to hot temperatures. Both dielectric constant and dielectric loss factor rapidly increased from -20°C …


Mobile Sensor Data Mining, Jeff Lockhart Fcrh '13 Dec 2013

Mobile Sensor Data Mining, Jeff Lockhart Fcrh '13

The Fordham Undergraduate Research Journal

At an ever increasing rate, the smartphones and other devices people carry with them in their everyday lives are packed with sensors and processing power. This provides an unprecedented opportunity to apply data mining techniques to people’s activities as they go about their daily lives, without changing their routine. The goal of the Wireless Sensor Data Mining (WISDM) Project is to explore the possibilities of data mining on these powerful mobile platforms.1 Data mining involves extracting knowledge from data using computer algorithms. A major sensor in these devices is the tri-axial accelerometer originally included for screen rotation and advanced gaming. …


Data Management In Cloud Environments: Nosql And Newsql Data Stores, Katarina Grolinger, Wilson A. Higashino, Abhinav Tiwari, Miriam Am Capretz Dec 2013

Data Management In Cloud Environments: Nosql And Newsql Data Stores, Katarina Grolinger, Wilson A. Higashino, Abhinav Tiwari, Miriam Am Capretz

Electrical and Computer Engineering Publications

: Advances in Web technology and the proliferation of mobile devices and sensors connected to the Internet have resulted in immense processing and storage requirements. Cloud computing has emerged as a paradigm that promises to meet these requirements. This work focuses on the storage aspect of cloud computing, specifically on data management in cloud environments. Traditional relational databases were designed in a different hardware and software era and are facing challenges in meeting the performance and scale requirements of Big Data. NoSQL and NewSQL data stores present themselves as alternatives that can handle huge volume of data. Because of the …


Water Vapor Movement In Freezing Aggregate Base Materials, Maile Anne Rogers Dec 2013

Water Vapor Movement In Freezing Aggregate Base Materials, Maile Anne Rogers

Theses and Dissertations

The objectives of this research were to 1) measure the extent to which water vapor movement results in water accumulation in freezing base materials; 2) evaluate the effect of soil stabilization on water vapor movement in freezing base materials; 3) determine if the corresponding changes in water content are sufficient to cause frost heave during winter; 4) determine if the corresponding changes in water content are sufficient to cause reductions in stiffness during spring; 5) evaluate relationships between selected material properties, freezing conditions, and the occurrence and impact of water vapor movement; and 6) numerically simulate heat and water movement …


A Dynamic Optimization Framework With Model Predictive Control Elements For Long Term Planning Of Capacity Investments In A District Energy System, Jose Luis Mojica Velazquez Dec 2013

A Dynamic Optimization Framework With Model Predictive Control Elements For Long Term Planning Of Capacity Investments In A District Energy System, Jose Luis Mojica Velazquez

Theses and Dissertations

The capacity expansion of a district heating system is studied with the objective of evaluating the investment decision timing and type of capacity expansion. District energy is an energy generation system that provides energy, such as heat and electricity, generated at central locations and distributed to the surrounding area. The study develops an optimization framework to find the optimal investment schedule over a 30 year horizon with the options of investing in traditional heating sources (boilers) or a next-generation combined heat and power (CHP) plant that can provide heat and electricity. In district energy systems, the investment decision on the …


Battery Energy Storage Systems To Mitigate The Variability Of Photovoltaic Power Generation, Heath Alan Gurganus Dec 2013

Battery Energy Storage Systems To Mitigate The Variability Of Photovoltaic Power Generation, Heath Alan Gurganus

Dissertations and Theses

Methods of generating renewable energy such as through solar photovoltaic (PV) cells and wind turbines offer great promise in terms of a reduced carbon footprint and overall impact on the environment. However, these methods also share the attribute of being highly stochastic, meaning they are variable in such a way that is difficult to forecast with sufficient accuracy. While solar power currently constitutes a small amount of generating potential in most regions, the cost of photovoltaics continues to decline and a trend has emerged to build larger PV plants than was once feasible. This has brought the matter of increased …


Condition Assessment Of Decommissioned Bridge Decks Treated With Waterproofing Membranes And Asphalt Overlays, Eric Scott Sumsion Dec 2013

Condition Assessment Of Decommissioned Bridge Decks Treated With Waterproofing Membranes And Asphalt Overlays, Eric Scott Sumsion

Theses and Dissertations

The objective of this research was to assess the condition of four decommissioned bridge decks treated with waterproofing membranes and asphalt overlays following the completion of their service lives. Large samples were cut from each of the bridge decks immediately prior to demolition and taken to the Brigham Young University Highway Materials Laboratory, where extensive sampling and testing was performed. Methods used to evaluate the condition of the bridge deck samples included visual inspection, hammer sounding, Schmidt rebound hammer testing, resistivity testing, half-cell potential testing, linear polarization testing, cover depth measurement, and chloride concentration measurement. The samples were removed from …


Developing Guidelines For Including Mobility-Based Performance Specifications In Highway Construction Contracts, Shawn J. Larson Dec 2013

Developing Guidelines For Including Mobility-Based Performance Specifications In Highway Construction Contracts, Shawn J. Larson

Theses and Dissertations

Construction zones can greatly affect the traffic flow on roadways, especially when lane closures are required. Traditionally, the Utah Department of Transportation (UDOT) has used traffic management specifications that only allow lane closures and road work to be done during predetermined hours or specifications that require a certain number of lanes to be open at all times. Recently, mobility-based work-zone traffic flow maintenance has been considered. This method requires continuous monitoring of mobility-based performance data and a mechanism to send alerts to the contractors when the mobility data does not meet the standards set by the specifications. UDOT recently tested …


A Kinetic Study Of Aqueous Calcium Carbonate, Derek Daniel Harris Dec 2013

A Kinetic Study Of Aqueous Calcium Carbonate, Derek Daniel Harris

Theses and Dissertations

Amorphous calcium carbonate (ACC) precipitation is modeled using particle nucleation, growth, and aggregation. The particles are tracked in terms of their radial size and particle density using direct quadrature method of moments (DQMOM). Four separate nucleation models are implemented and are compared to experimental data. In discord with a recent study, it is shown that classical nucleation, coupled with equilibrium chemistry, is in good agreement with experimental data. Novel nucleation mechanisms are presented which fit the experimental data with slightly greater accuracy. Using equilibrium chemistry it is shown that the equilibrium value of ACC is pKeq = 7.74 at 24C, …


Frost Susceptibility Of Base Materials Treated With Asphalt Emulsion, Noelle Anderson Dec 2013

Frost Susceptibility Of Base Materials Treated With Asphalt Emulsion, Noelle Anderson

Theses and Dissertations

The objective of this research was to investigate emulsion-treated base (ETB) frost susceptibility in terms of both freeze-thaw cycling and frost heave. The research performed in this study involved laboratory testing of ETB materials sampled from both the Redwood Road and 7800 South reconstruction projects in northern Utah. The effects of freeze-thaw cycling were evaluated by comparing the stiffness and strength of tested specimens to the same properties of control specimens not subjected to freeze-thaw cycling. Frost heave testing enabled evaluation of the effects of emulsion content and degree of curing on the volumetric stability of ETB materials during sustained …


2013 Fall Engr333 Project Final Report, 2013 Fall Engr333 Dec 2013

2013 Fall Engr333 Project Final Report, 2013 Fall Engr333

ENGR 333

During the fall of 2013, the Engineering 333 class was asked the question, “what would it take for Calvin College to operate a biofuel vehicle from campus resources?” The three primary considerations included:

  • Determining the optimal biofuel feedstock in terms of availability, transportation, and processing.
  • Selecting a biofuel vehicle for conversion or purchase to operate on the selected feedstock.
  • Designing the infrastructure and process required for operating the selected biofuel vehicle. The design and research described below proposes an environmentally sustainable and cost-effective method for integrating a biofuel vehicle into Calvin’s existing infrastructure.


Liquid Core Waveguide Sensors With Single And Multi-Spot Excitation, Lynnell Uilani Wai Yee Zempoaltecatl Dec 2013

Liquid Core Waveguide Sensors With Single And Multi-Spot Excitation, Lynnell Uilani Wai Yee Zempoaltecatl

Theses and Dissertations

Using silicon based microfabrication and materials, a photonic platform, capable of single bioparticle analysis, has been developed. This platform combines liquid and hollow core waveguides on the micron-scale (5 µm x 12 µm) to isolate femtoliter sized sample volumes. Fluorescence excitation and signals in the visible range are directed into and out of the sample volume at an orthogonal angle to maximize signal-to-noise. In order to guide light in a low-index material antiresonant reflecting optical waveguides (ARROWs) were incorporated into the platform. This thesis reveals the development path of these structures over several device generations including innovations in material, geometries, …


Reduced Row Echelon Form And Non-Linear Approximation For Subspace Segmentation And High-Dimensional Data Clustering, Akram Aldroubi, Ali Sekmen Dec 2013

Reduced Row Echelon Form And Non-Linear Approximation For Subspace Segmentation And High-Dimensional Data Clustering, Akram Aldroubi, Ali Sekmen

Computer Science Faculty Research

Given a set of data W={w1,…,wN}∈RD drawn from a union of subspaces, we focus on determining a nonlinear model of the form U=⋃i∈ISi, where {Si⊂RD}i∈I is a set of subspaces, that is nearest to W. The model is then used to classify W into clusters. Our approach is based on the binary reduced row echelon form of data matrix, combined with an iterative scheme based on a non-linear approximation method. We prove that, in absence of noise, our approach can find the number of subspaces, their dimensions, and an orthonormal basis for each subspace Si. We provide a comprehensive analysis …


Multiplexed Fiber-Ring Laser Sensors For Ultrasonic Detection, Tongqing Liu, Lingling Hu, Ming Han Dec 2013

Multiplexed Fiber-Ring Laser Sensors For Ultrasonic Detection, Tongqing Liu, Lingling Hu, Ming Han

Department of Electrical and Computer Engineering: Faculty Publications

We propose and demonstrate a multiplexing method for ultrasonic sensors based on fiber Bragg gratings (FBGs) that are included inside the laser cavity of a fiber-ring laser. The multiplexing is achieved using add-drop filters to route the light signals, according to their wavelengths, into different optical paths, each of which contains a separate span of erbium-doped fiber (EDF) as the gain medium. Because a specific span of EDF only addresses a single wavelength channel, mode completion is avoided and the FBG ultrasonic sensors can be simultaneously demodulated. The proposed method is experimentally demonstrated using a two-channel system with two sensing …


Modified Sodium Diuranate Process For The Recovery Of Uranium From Uranium Hexafluoride Transport Cylinder Wash Solution, Austin Dean Meredith Dec 2013

Modified Sodium Diuranate Process For The Recovery Of Uranium From Uranium Hexafluoride Transport Cylinder Wash Solution, Austin Dean Meredith

Theses and Dissertations

Uranium hexafluoride (UF6) containment cylinders must be emptied and washed every five years in order to undergo recertification, according to ANSI standards. During the emptying of the UF6 from the cylinders, a thin residue, or heel, of UF6 is left behind. This heel must be removed in order for recertification to take place.

To remove it, the inside of the containment cylinder is washed with acid and the resulting solution generally contains three or four kilograms of uranium. Thus, before the liquid solution can be disposed of, the uranium must be separated. A modified sodium diuranate …


Fundamental Experimental Studies In Scaling, Blast Mitigation And Material Processing, Xing Zhao Dec 2013

Fundamental Experimental Studies In Scaling, Blast Mitigation And Material Processing, Xing Zhao

Theses and Dissertations

In this work, two separate research efforts are discussed. They include experimental studies in (1) Scaling and Blast Mitigation and (2) Scaling in Friction Stir Extrusion. In both studies, the primary experimental measurement method is three-dimensional digital image correlation (3D-DIC), a non-contacting full-field measurement method that is applicable for both high-rate loading and quasi-static loading conditions.

Scaling and Blast Mitigation Studies:

A series of properly scaled structures was subjected to buried blast loading conditions via detonation of a small explosive buried in saturated sand. Using high speed stereo-vision systems to record the deformations of selected regions on the upper surface …


Applying Best Practices To Florida Local Government Retrofit Programs, Florida Solar Energy Center, Janet Mcilvaine Dec 2013

Applying Best Practices To Florida Local Government Retrofit Programs, Florida Solar Energy Center, Janet Mcilvaine

FSEC Energy Research Center®

In some communities, local government and non-profit entities have funds to purchase and renovate distressed, foreclosed homes for resale in the affordable housing market. Numerous opportunities to improve whole house energy efficiency are inherent in these comprehensive renovations. BA-PIRC worked together in a multiyear field study making recommendations in individual homes, meanwhile compiling improvement costs, projected energy savings, practical challenges, and labor force factors surrounding common energy-related renovation measures. The field study, Phase 1 of this research, resulted in a set of best practices appropriate to the current labor pool and market conditions in central Florida to achieve projected annual …


Network Burst Monitoring And Detection Based On Fractal Dimension With Adaptive Time-Slot Monitoring Mechanism, Hsiao-Wen Tin, Shao-Wei Leu, Shun-Hsyung Chang, Gene Eu Jan Dec 2013

Network Burst Monitoring And Detection Based On Fractal Dimension With Adaptive Time-Slot Monitoring Mechanism, Hsiao-Wen Tin, Shao-Wei Leu, Shun-Hsyung Chang, Gene Eu Jan

Journal of Marine Science and Technology–Taiwan

This study proposed an approach to measure the burstiness of network traffic based on fractal dimensions (FDs). By definition, burstiness is the degree of variation in network traffic. This study defined two types of FDs: (1) the FD of network traffic that describes the flow variation of network traffic, and (2) the FD of the range that describes the degree of flow dispersal. The proposed method uses an adaptive time-slot monitoring mechanism to monitor the network. The relevant FDs are derived from measurements obtained during each time slot in a monitoring window. This study conducted experiments using NS2 simulation data. …


The Least Squares Trefftz Method And The Method Of External Source For The Eigenfrequencies Of Waveguides, Hui-Ming Fang, Chia-Ming Fan, Yan-Cheng Liu, Sung-Shan Hsiao Dec 2013

The Least Squares Trefftz Method And The Method Of External Source For The Eigenfrequencies Of Waveguides, Hui-Ming Fang, Chia-Ming Fan, Yan-Cheng Liu, Sung-Shan Hsiao

Journal of Marine Science and Technology–Taiwan

In this study, the least squares Trefftz method (LSTM) is adopted for analyzing the eigenfrequencies problems governed by homogeneous Helmholtz equations. The Trefftz method, one kind of boundary-type meshless collocation methods, does not need mesh generation and numerical quadrature. Since the system of linear algebraic equations obtained by Trefftz method is highly ill-conditioned, the least squares method is adopted to stabilize the numerical scheme in this study. In the eigenproblem, the response amplitudes from an external source are used to determine the resonant frequencies. By adding an external source, the homogeneous boundary condition becomes inhomogeneous. Then we can employ the …


An Effective Illumination Compensation Method For Face Recognition, Yea-Shuan Huang, Chu-Yung Li Dec 2013

An Effective Illumination Compensation Method For Face Recognition, Yea-Shuan Huang, Chu-Yung Li

Journal of Marine Science and Technology–Taiwan

Face recognition is very useful in many applications, such as safety and surveillance, intelligent robot, and computer login. The reliability and accuracy of such systems will be influenced by the variation of background illumination. Therefore, how to accomplish an effective illumination compensation method for human face image is a key technology for face recognition. Our study uses several computer vision techniques to develop an illumination compensation algorithm to processing the single channel (such as grey level or illumination intensity) face image. The proposed method mainly consists of three processing modules: (1) Homomorphic Filtering, (2) Ratio Image Generation, and (3) Anisotropic …


Automatic Location For Multi-Symbology And Multiple 1d And 2d Barcodes, Daw-Tung Lin, Chin-Lin Lin Dec 2013

Automatic Location For Multi-Symbology And Multiple 1d And 2d Barcodes, Daw-Tung Lin, Chin-Lin Lin

Journal of Marine Science and Technology–Taiwan

Multi-symbology barcode location is a practical and challenging issue. Image-based barcode recognition techniques are robust and extendable approaches for reading versatile one-dimensional (1D) and two-dimensional (2D) barcodes. Most methods may work for a single 1D or 2D barcode or rely on a unique pattern to locate a single 1D or 2D barcode. This work proposes a general localization framework for extraction of real barcodes under complex backgrounds when multiple symbology types exist in the same snapshot for 1D barcodes, 2D barcodes, or both. There are five steps of the proposed algorithm: image grayscale conversion, adaptive thresholding, application of a modified …


Physical Models For Simulating Ship Stability And Hydrostatic Motions, Shyh-Kuang Ueng Dec 2013

Physical Models For Simulating Ship Stability And Hydrostatic Motions, Shyh-Kuang Ueng

Journal of Marine Science and Technology–Taiwan

In this paper, efficient physics models are presented for simulating ship hydrostatic motions caused by sea waves, cargoes and flooding water. Based on the stability theory of ship, a ship is regarded as a floating body whose stability is indicated by its gravity, buoyancy and meta centers. These stability centers are influenced by cargoes, sea waves, flooding water and the ship mass. Variations of these stability centers create torques and forces which cause the ship to heave, pitch and roll. Because of the irregularity of the ship shape, analytical solutions of these stability centers do not exist. In this work, …


Traffic Monitoring And Event Analysis Based On Integrated Multivideo And Petri Net Process, Chang-Lung Tsai Dec 2013

Traffic Monitoring And Event Analysis Based On Integrated Multivideo And Petri Net Process, Chang-Lung Tsai

Journal of Marine Science and Technology–Taiwan

Decreasing traffic accidents and events are one of the most important responsibilities for all of the governments in the world. However, it is difficult to exactly measuring the traffic condition. To find out the root cause of traffic accidents and restore the occurrence of traffic events, a traffic monitor and event analysis mechanism based on multi-videos processing and Petri net analysis techniques is proposed. In which, the traffic information is collected through the deployment of cameras at intersection of heavy traffic area. After then, all of the collected information is provided for constructing multiviewpoint traffic model. The significant features are …


A Heat Island Observation Via Modis And Concurrent Helicopter-Borne Ir Imager, Tsung-Hua Kuo, Gin-Rong Liu, Tang-Huang Lin, Chia-Wen Lan, Chi-Ping Huang Dec 2013

A Heat Island Observation Via Modis And Concurrent Helicopter-Borne Ir Imager, Tsung-Hua Kuo, Gin-Rong Liu, Tang-Huang Lin, Chia-Wen Lan, Chi-Ping Huang

Journal of Marine Science and Technology–Taiwan

In this study, observations and aerial surveys were conducted in delineating the heat island patterns. Concurrent datasets from the satellite-borne MODIS sensor and helicopter-borne thermal IR imager were employed. The sampling data in this experiment covered an area exceeding 100 km2 in Taiwan’s western plain. A more than 10°C temperature difference between different sampling points could be observed in this area. The relationship between the surface temperature and vegetation index values was also showed. Results showed that the surface canopy and the air humidity together played an important role in the surface temperature increase.


Integrating Information Into The Engineering Design Process, Michael Fosmire, David Radcliffe Dec 2013

Integrating Information Into The Engineering Design Process, Michael Fosmire, David Radcliffe

Purdue University Press Books

Engineering design is a fundamental problem-solving model used by the discipline. Effective problem-solving requires the ability to find and incorporate quality information sources. To teach courses in this area effectively, educators need to understand the information needs of engineers and engineering students and their information gathering habits. This book provides essential guidance for engineering faculty and librarians wishing to better integrate information competencies into their curricular offerings. The treatment of the subject matter is pragmatic, accessible, and engaging. Rather than focusing on specific resources or interfaces, the book adopts a process-driven approach that outlasts changing information technologies.

After several chapters …