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Post-Processing Resolution Enhancement Of Open Skies Photographic Imagery, Daniel E. Sperl Mar 2000

Post-Processing Resolution Enhancement Of Open Skies Photographic Imagery, Daniel E. Sperl

Theses and Dissertations

The Treaty on Opens Skies allows any signatory nation to fly a specifically equipped reconnaissance aircraft anywhere over the territory of any other signatory nation. For photographic images, this treaty allows for a maximum ground resolution of 30 cm. The National Air Intelligence Center (NAIC), which manages implementation of the Open Skies Treaty for the US Air Force, wants to determine if post-processing of the photographic images can improve spatial resolution beyond 30 cm, and if so, determine the improvement achievable. Results presented in this thesis show that standard linear filters (edge and sharpening) do not improve resolution significantly and …

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Monotonic And Fatigue Loading Behavior Of An Oxide/Oxide Ceramic Matrix Composite, Steven G. Steel Mar 2000

Monotonic And Fatigue Loading Behavior Of An Oxide/Oxide Ceramic Matrix Composite, Steven G. Steel

Theses and Dissertations

This thesis evaluates an oxide/oxide ceramic matrix composite, N720/A, for high temperature aerospace applications. The composite consists of a porous alumina matrix reinforced by ten plies of Nextel 720 fibers in a balanced 8 harness satin weave. Monotonic tensile and fatigue tests were performed at room temperature and 1200 °C. The effect of moisture on 1200 °C fatigue life was also examined. Modulus, maximum and minimum strain, and stress-strain hysteresis were monitored to characterized fatigue damage. Retained strength of all specimens that survived 100000 fatigue cycles was tested. Microscopy and fractography were used to examine damage and fracture surfaces. N720/A …

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Sensitivity Studies On A Limited Area Mesoscale Model: An Examination Of Lateral Boundary Placement, Grid Resolution And Nesting Type, Robert A. Stenger Mar 2000

Sensitivity Studies On A Limited Area Mesoscale Model: An Examination Of Lateral Boundary Placement, Grid Resolution And Nesting Type, Robert A. Stenger

Theses and Dissertations

With the advances of computer technology in recent years, limited area mesoscale models are being used to produce operational forecasts on a broader scale worldwide than ever before. The past limitations of computational resources have caused previous research efforts to focus more on model physics, thus creating a gap in the number of sensitivity studies conducted on these models. This research is intended to bridge a gap in the apparent paucity of sensitivity studies on the limited area model (LAM). The Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model 5 was utilized to conduct sensitivity studies on lateral boundary …

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The Air Force Institute Of Technology (Afit) Micro Electro-Mechanical Systems (Mems) Interferometric Gyroscope (Mig), Jeremy P. Stringer Mar 2000

The Air Force Institute Of Technology (Afit) Micro Electro-Mechanical Systems (Mems) Interferometric Gyroscope (Mig), Jeremy P. Stringer

Theses and Dissertations

With the invention of Micro Electro-Mechanical Systems (MEMS) it has become possible to fabricate micro-inertial sensors. These new sensors have application in creating autonomous guided weapons systems. New technologies like Micro Unmanned Aerial Vehicles (UAVs), which cannot use conventional inertial sensors, rely on technologies like micro-inertial sensors to operate. Also, such sensors have the capability to reduce both power and space consumption on conventional aircraft. This technology is not yet mature, and current micro-inertial sensors do not have the accuracy required for highly precise navigation. To try to increase the accuracy of micro-inertial sensors, researchers are turning toward micro-optical gyroscopes. …

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Organizational And Individual Effects On The Reporting Of Wrongdoing In The Workplace, Brian M. Stumpe Mar 2000

Organizational And Individual Effects On The Reporting Of Wrongdoing In The Workplace, Brian M. Stumpe

Theses and Dissertations

The study focuses on the organizational context in which the act of whistle-blowing occurs within organizations. The study suggests that many aspects of the context in which whistle-blowing actually occurs may be within the span of control of managers. Thus, management can possibly take steps to after certain aspects of the organizational context and ensure that organizational members are willing to report wrongdoing observed within their organization. To fulfill this objective, the study analyzes survey responses taken from military members' and civilian employees' responses to a 1997 survey distributed throughout the Aeronautical Systems Center (ASC), Wright Patterson Air Force Base …

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A Pharmacokinetic Study Of The Effects Of Stress On Chemical Exposure, Sierra H. Suhajda Mar 2000

A Pharmacokinetic Study Of The Effects Of Stress On Chemical Exposure, Sierra H. Suhajda

Theses and Dissertations

Following the Gulf War there were many concerns raised about human exposure to the combination of chemicals and stress. Stress causes several changes in basic functions of a human body, from breathing and blood flow changes to hormonal and enzyme changes, and increased permeability of the blood-brain barrier. Each of these changes can strongly influence chemical uptake, distribution, and accumulation in the body. The purpose of this thesis was to model and predict the changes that will occur when stress is combined with chemical exposure. Physiologically-based pharmacokinetic (PBPK) modeling is one tool that can be used to visualize, predict, and …

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Simulations Of Flowing Supercritical N-Decane, Jeffery T. Thornburg Mar 2000

Simulations Of Flowing Supercritical N-Decane, Jeffery T. Thornburg

Theses and Dissertations

The Air Force is interested in the research of supercritical jet and rocket fuels, as well as the effects of thermally induced fuel degradation. As future flight vehicles travel at ever increasing Mach numbers, greater heat loads will be imposed upon the fuel. The primary purpose of this study is to develop a computational model for predicting fuel decomposition and bulk fuel temperatures in a stimulated heated flow reactor. The System for Thermal Diagnostic Studies (STDS), located in the Air Force Research Laboratory's Fuels Branch, is used to analyze fuels under supercritical temperatures and pressures. Computational simulations of the STDS …

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A Study Of Morning Radiation Fog Formation, Jimmie L. Trigg Jr. Mar 2000

A Study Of Morning Radiation Fog Formation, Jimmie L. Trigg Jr.

Theses and Dissertations

This research focuses on developing a linear regression formula that forecasters in the Midwest can use to accurately anticipate the formation of radiation fog. This was accomplished in three stages. First a study of the surface and upper air parameters and processes required to develop radiation fog were identified and explored. Next, a linear regression technique was applied to the 23 parameters identified. The top four indicators were then reprocessed and a new linear regression equation was developed. Finally, the new regression equation was compared to an existing fog forecasting technique. The existing forecast technique selected was the 2nd Weather …

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Improving Uav Handling Qualities Using Time Delay Compensation, Andrew J. Thurling Mar 2000

Improving Uav Handling Qualities Using Time Delay Compensation, Andrew J. Thurling

Theses and Dissertations

This research investigated control loop time delay and its effect on UAV handling qualities. Compensation techniques to improve handling qualities in the presence of varying amounts of time delay were developed and analyzed. One technique was selected and successfully flight-tested on a UAV. Flight-testing occurred at a constant flight condition with varying levels of additional time delay introduced into the control loop. Research pilots performed a pitch tracking task and gave Cooper-Harper ratings and comments. Tracking errors were used as a quantitative measure of Pilot/Display/UAV system performance. Predictive pitch compensation was found to significantly reduce pilot workload and improve Cooper-Harper …

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Simulation Evaluation Of The Combat Value Of A Standoff Precision Airdrop Capability, Michael W. Varner Mar 2000

Simulation Evaluation Of The Combat Value Of A Standoff Precision Airdrop Capability, Michael W. Varner

Theses and Dissertations

This project is a simulation evaluation of the developmental standoff precision airdrop (SOPAD) capability. SOPAD is a new technology under consideration to deliver supplies to forward-deployed units using either a semi-rigid wing or a guided parafoil. These delivery systems allow airdrop of supplies from altitudes of 25,000 feet and distances 25 miles from the delivery point. Using global positioning system guidance, on board navigational computers, and automatic steering mechanisms, the delivery system flies to the target following a designated flight plan. The concept includes delivering supplies to remote and potentially hostile areas without endangering the supply aircraft. In addition, supplies …

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Optical Metrology Of Adaptive Membrane Mirrors, John W. Wagner Mar 2000

Optical Metrology Of Adaptive Membrane Mirrors, John W. Wagner

Theses and Dissertations

Current space-based imaging platforms are significantly constrained in both size and weight by the launch vehicle. Increased payload size and weight results in increased cost and a decrease in launch responsiveness. The USAF Scientific Advisory Board (SAB) identified "Large lightweight structures for optics and antennas" as a revolutionary primary technology to be developed for the Air Force of the 21st Century. A membrane primary mirror in a space-based imaging system has the ability to overcome current payload constraints and meet evolutionary needs of the future. The challenge of membrane optics in space is the process of implementing adaptive optics technology …

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Enhancing A Virtual Distributed Library User Interface Via Server-Side User Profile Caching, Jason T. Ward Mar 2000

Enhancing A Virtual Distributed Library User Interface Via Server-Side User Profile Caching, Jason T. Ward

Theses and Dissertations

Various Department of Defense (DoD) agencies archive terabytes of intelligence imagery and electrooptical signature data. The Air Force Research Laboratory, Sensors Directorate (AFRL/SN), is tasked with creating and managing a virtual distributed library that facilitates secure, detailed queries across these distributed holdings using the internally developed Advanced Query Tool (AQT). In this research, a methodology is proposed to utilize user profiling techniques to augment a digital library. As part of this methodology, product-oriented usability analysis metrics are introduced that quantitatively verify the usability of an interface. The methodology is applied to the AFRL/SN's Virtual Distributed Laboratory AQT and subsequently analyzed …

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Improving The Analyst And Decision-Maker’S Perspective Through Uncertainty Visualization, Evan T. Watkins Mar 2000

Improving The Analyst And Decision-Maker’S Perspective Through Uncertainty Visualization, Evan T. Watkins

Theses and Dissertations

This thesis constructs the Taxonomy of Uncertainty and an approach for enhancing the information in decision support systems. The hierarchical categorization of numerous causes for uncertainty defines the taxonomy, which fostered the development of a technique for visualizing uncertainty. This technique is fundamental to expressing the multi-dimensional uncertainty that can be associated with any object. By including and intuitively expressing uncertainty, the approach facilitates and enhances intuition and decision-making without undue information overload. The resulting approach for enhancing the information involves recording uncertainty, identifying the relevant items, computing and visualizing uncertainty, and providing interaction with the selection of uncertainty. A …

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Explicitly Modeling Hierarchically Heterogeneous Software Architectures In An Object-Oriented Formal Transformation System, Darin L. Williams Mar 2000

Explicitly Modeling Hierarchically Heterogeneous Software Architectures In An Object-Oriented Formal Transformation System, Darin L. Williams

Theses and Dissertations

Formal software transformation systems are software development environments typified by the semi-automated application of a series of correctness-preserving transformations to formal data models. The range of software architectures such systems are capable of producing is often restricted by the limited ability to accept high-level design inputs as constraints on the transformation process. When architectural inputs are acceptable, often the modeling language excludes the explicit representation of architectural constructs and provides, at best, an extremely limited architectural analysis capability. This research defines a high-level taxonomy of software architectures and proposes a way to explicitly model a broad class of architectures by …

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Use Of Genetic Algorithms To Characterize Groundwater Contamination Source Areas, Chaz M. Williamson Mar 2000

Use Of Genetic Algorithms To Characterize Groundwater Contamination Source Areas, Chaz M. Williamson

Theses and Dissertations

In this work, genetic algorithms (GAs) were used to help interpret tracer breakthrough curves from partitioning interwell tracer tests (PITTs) conducted at Hill AFB, Utah by researchers from the University of Florida. Two transport models were developed to simulate tracer transport in the test cells. One model assumed the cell consisted of multiple layers, and that transport in each layer could he described by the one-dimensional advective/dispersive equation. The second model also assumed multiple layers, and modeled transport in the individual layers as advective transport through 100 tubes. Transport times were represented by a stochastic (lognormal) distribution. The model solutions …

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Multiagent Systems Engineering: A Methodology For Analysis And Design Of Multiagent Systems, Mark F. Wood Mar 2000

Multiagent Systems Engineering: A Methodology For Analysis And Design Of Multiagent Systems, Mark F. Wood

Theses and Dissertations

This thesis defines a methodology for the creation of multiagent systems, the Multiagent Systems Engineering (MaSE) methodology. The methodology is a key issue in the development of any complex system and there is currently no standard or widely used methodology in the realm of multiagent systems. MaSE covers the entire software lifecycle, starting from an initial prose specification, and creating a set of formal design documents in a graphical style based on a formal syntax. The final product of MaSE is a diagram describing the deployment of a system of intelligent agents that communicate through structured conversations. MaSE was created …

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A Greedy Multiple-Knapsack Heuristic For Solving Air Mobility Command’S Intratheater Airlift Problem, Nicholas J. Zeisler Mar 2000

A Greedy Multiple-Knapsack Heuristic For Solving Air Mobility Command’S Intratheater Airlift Problem, Nicholas J. Zeisler

Theses and Dissertations

This research develops a methodology using a greedy heuristic to solve Air Mobility Command's intratheater airlift scenario as a multiple knapsack problem. The objective is to maximize throughput in a theater given a vehicle mixture and assignment scheme. The model allows for a heterogeneous, user defined vehicle mix in a theater consisting of up to five bed down locations and up to seven forward operating locations. First, we preprocess routes, eliminating the large number of unattractive route choices in the problem. Then using a greedy heuristic, we select routes and assign them to aircraft located at any or all of …

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A Performance Analysis Of A Joint Lmds/ Satellite Communication Network, Ronald J. Zwickel Mar 2000

A Performance Analysis Of A Joint Lmds/ Satellite Communication Network, Ronald J. Zwickel

Theses and Dissertations

The goal of this research is to provide a performance analysis of a joint terrestrial/ satellite communication network. The systems of interest are the Local Multipoint Distribution Service (LMDS) terrestrial system and the proposed Teledesic satellite network. This analysis is performed using the OPNET network simulation tool. Simulations are run for twelve separate scenarios involving three factors which include: number of users, modulation type, and Quality of Service (QoS). The key metrics for characterizing simulation scenarios are the end-to-end delay, bit error rate, and average system throughput. The results obtained display the benefit of improved throughput, approximately 20 Mbps for …

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Active And Adaptive Control For Payload Launch Vibration Isolation, Julian R. Jarosh Mar 2000

Active And Adaptive Control For Payload Launch Vibration Isolation, Julian R. Jarosh

Theses and Dissertations

The Department of Defense has identified launch vibration isolation as a major research interest. Reducing the loads a satellite experiences during launch will greatly enhance its reliability and lifetime, and reduce payload structural mass. DoD space programs stand to benefit significantly from advances in vibration isolation technology. This study explores potential hybrid vibration isolation using active and adaptive control with a passive vibration isolator. The active control methods are Proportional-Integral-Derivative (PID) control and a skyhook damper. Lyapunov analysis is used to develop the structural adaptive control scheme. Simulink and Matlab simulations investigate these control methodologies on a lumped mass dynamic …

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Empirical Evaluation Of The Civil Engineer Career Pyramid And Career Guidance, Travis K. Leighton Mar 2000

Empirical Evaluation Of The Civil Engineer Career Pyramid And Career Guidance, Travis K. Leighton

Theses and Dissertations

Air Force civil engineer officers rely on published guidance to assist in establishing their career objectives. This thesis uses empirical data to evaluate the published Air Force career guidance. The data set is comprised of complete duty histories from all active duty lieutenant colonels in the civil engineer career field. The guidance implies a career path to become a civil engineer squadron commander but provides no empirical validation. This thesis follows a rigorous procedure to objectively evaluate the Air Force guidance. The guidance is translated into 24 research questions based on its main tenets. Each duty occurrence is categorized by …

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Chemical Mechanical Polishing Optimization For 4h-Sic, Craig L. Neslen Mar 2000

Chemical Mechanical Polishing Optimization For 4h-Sic, Craig L. Neslen

Theses and Dissertations

Scratch free surfaces are required for substrates used in epitaxial growth. Silicon carbide (SiC) is a substrate material that is used in the epitaxial growth of SiC, GaN, and InGaN electronic devices. Preliminary chemical mechanical polishing (CMP) studies of 1 3/8" 4H-SiC wafers were performed in an attempt to identify the polishing parameter values that result in a maximum material removal rate and thus reduce substrate polishing time. Previous studies reported increased material removal rates associated with increasing polishing temperature, slurry pH, pressure, and polishing pad speed. In the current study, the effects of temperature, slurry pH, polishing pressure, and …

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Self-Reported Teacher Job Satisfaction And Perception Of Administrative Listening Skills, John David Tackett Jan 2000

Self-Reported Teacher Job Satisfaction And Perception Of Administrative Listening Skills, John David Tackett

Theses and Dissertations

The purpose of the study was to determine the existence of a relationship between teacher self-reported job satisfaction and the perception of administrative listening skills. Thirty secondary schools were chosen from the three largest school districts in central Arkansas. Twenty-nine schools participated in the study. As defined by the Arkansas Department of Education, the term secondary includes grades seven through twelve; therefore, three levels of schools were included in the sample: high school, junior high school, and middle school. The predictor variable was administrative listening and the criterion variable was job satisfaction with supervision. Instrumentation included the Leadership Behavior Description …

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Advanced Practice Analysis Of Physical Therapy In Women’S Health, Jean M. Irion Jan 2000

Advanced Practice Analysis Of Physical Therapy In Women’S Health, Jean M. Irion

Theses and Dissertations

The primary purpose of this study was to determine the knowledge, skills, and behaviors of advanced physical therapy practitioners in women's health. The study also sought to identify patient populations/diagnoses served by advanced physical therapist practitioners in women's health. A three-round modified Delphi research technique was used to obtain consensus from a panel of experts. The panel was comprised of highly qualified physical therapists with extensive knowledge and experience in the practice area of women's health. A panel of academic experts was used to review the third-round results of the study. The panel of experts answered a survey which included …

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A Study Of Discipline Policies And Dropout Rates In Selected North Dakota Public Schools, Carol A. Jabs Jan 2000

A Study Of Discipline Policies And Dropout Rates In Selected North Dakota Public Schools, Carol A. Jabs

Theses and Dissertations

No abstract provided.

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Analysis Of The Livestock Production System Of The Poroma Community In The 2 Section Of The Oropeza Province, Department Of Chuquisaca, Freddy Claudio Ramí­Rez Serrudo Jan 2000

Analysis Of The Livestock Production System Of The Poroma Community In The 2 Section Of The Oropeza Province, Department Of Chuquisaca, Freddy Claudio Ramí­Rez Serrudo

Theses and Dissertations

This study was performed in the Poroma community of the Oropeza Province, in the department of Chuquisaca. The Poroma community is characterized by a high poverty level among its members due to a number of different factors. Some of the major factors include: a restricted market, small farms, an absence of support systems, and a lack of support for agricultural development. This lack of support is seen in areas such as: research, roads, electricity, technical assistance, marketing systems, organization, and institutions that support rural development. Numerous studies on the production systems of farmers have described and analyzed the agricultural components …

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Evaluation Of 4 Small Doses Of Fertilizer In Growing Maize (Zea Mays L.) In Two Communities Of San Juan Ermita, Chiquimula, Victor Estuardo Villalta Garcia Jan 2000

Evaluation Of 4 Small Doses Of Fertilizer In Growing Maize (Zea Mays L.) In Two Communities Of San Juan Ermita, Chiquimula, Victor Estuardo Villalta Garcia

Theses and Dissertations

Corral de Piedra and Salitron are two communities located in the municipality of San Juan Ermita, which is in the department of Chiquimula, Guatemala. In both communities, the land has very sloped topography with slope grades ranging from 12 to 55%. Agriculture is the main production activity with corn (Zea mays L.) and beans (Phaseolus vulgaris) being the crops of greatest economic importance. These crops are planted through a system of sequential association commonly called relay. First, corn is planted at the beginning of the rainy season (May or June). Once it has completed its reproductive cycle, beans are planted …

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The Availability And The Use Of Basic Services In Relation To The Nutritional Status, Acute Diarrhetic Diseases And Acute Respiratory Infections In Children Under Five Years Of Age In Three Rural Communities Of The Imbabura Province During The 1998-1999 Period, Margarita Caicedo Ceron Jan 2000

The Availability And The Use Of Basic Services In Relation To The Nutritional Status, Acute Diarrhetic Diseases And Acute Respiratory Infections In Children Under Five Years Of Age In Three Rural Communities Of The Imbabura Province During The 1998-1999 Period, Margarita Caicedo Ceron

Theses and Dissertations

To a large degree, the political and economic conditions of third world countries influence poverty levels, especially in rural areas. This poverty affects the availability of basic services, such as potable water, refuse elimination, housing, and sewage systems. As a consequence of these deficiencies, more diseases are transmitted through the water and environment. These diseases include acute diarrhea and acute respiratory infections in children younger than five years of age. Consequently, it is important to have available water and sewage elimination to control these diseases among children and the general population.

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Evaluation Of Forty-Two Corn (Zea Mays L.) Genotypes And Their Tolerance To Drought In Chiquimula, Servin Ardany Flores Galdámez Jan 2000

Evaluation Of Forty-Two Corn (Zea Mays L.) Genotypes And Their Tolerance To Drought In Chiquimula, Servin Ardany Flores Galdámez

Theses and Dissertations

The Corral de Piedra community is located in Chiquimula, Guatemala. The main agricultural activities are corn and bean production, small-scale gardens, and small animal production, such as poultry and pigs. The crop areas are predominantly located on lands with slopes between 12 and 55%, presenting low fertility conditions and poor moisture retention capabilities. In addition, local crop varieties have low productivity potentials and the winter season is characterized by poorly distributed and erratic periods of rain. The Benson Institute introduced a technology transfer model to increase and diversify agricultural production, while preserving current natural resources. An integral part of this …

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Agro-Socio-Economic Evaluation Of Three Rural Communities In The Colta Canton Of The Chimborazo Province, Ivan Asaquibay Paucar Jan 2000

Agro-Socio-Economic Evaluation Of Three Rural Communities In The Colta Canton Of The Chimborazo Province, Ivan Asaquibay Paucar

Theses and Dissertations

The faculty of natural resources, School of Agricultural Engineering of ESPOCH, with an agreement since 1992 with the Benson Institute of Brigham Young University has been working with the development of small scale production before its diffusion it is necessary to know the real social- economic conditions and the technological levels of the most important harvests of the communities, that when this model is involved in the aspects that affect the production. For this reason this investigation was made necessary in which the following objectives were raised: 1. Evaluate the social-economic conditions of the communities of San Lorenzo of Cahuiña, …

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Application Of Dietary Guidelines For Guatemala In Three Rural Communities Of Chiquimula, Sandra Liseth Salazar Donis Jan 2000

Application Of Dietary Guidelines For Guatemala In Three Rural Communities Of Chiquimula, Sandra Liseth Salazar Donis

Theses and Dissertations

In Guatemala, nutritional problems are directly related to the difficulty to purchase food fit for human consumption due to low family incomes as well as low nutritional education. This situation motivated the realization of the present study whose main objective was to apply the dietary guidelines for Guatemala in three rural communities of Chiquimula. All three communities were previously aided by Benson Institute efforts to promote changes in eating behavior. The sample was comprised of mothers from the El Pinalito, El Guayabo, and Maraxco communities of the department of Chiquimula. There were eight mothers, four literate and four illiterate, from …

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