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Quantification Of Marine Sediment Properties From Planar And Volumetric Pore Geometries, Allen Hagerman Reed
Quantification Of Marine Sediment Properties From Planar And Volumetric Pore Geometries, Allen Hagerman Reed
LSU Doctoral Dissertations
Pore geometry and topology are important determinants of sediment physical properties, such as porosity and permeability. They also influence processes that occur in the sediment, such as acoustic propagation, attenuation, and dispersion, single- and multi-phase fluid flow, and hydrodynamic dispersion. This study uses images to evaluate pore geometry and topology of ooid (subspherical particles) and siliclastic (angular quartz) sand that was collected from the marine environment south of Bimni Bahamas and Ft. Walton Beach, FL, respectively. Image analysis techniques and predictive tools enable insight into the relationships among sediment pore geometry, topology, and physical properties for these differently shaped sands. …
An Investigation Of The 150-Hour Requirement In Developing Personal Competencies In Accounting Education, Laura Davis Delaune
An Investigation Of The 150-Hour Requirement In Developing Personal Competencies In Accounting Education, Laura Davis Delaune
LSU Doctoral Dissertations
This study investigated if accounting graduates from Louisiana State University, a public institution, perceived that their accounting curriculum enhanced the development of their personal competencies of professional demeanor, problem solving/decision making, interaction, leadership, and communication. A survey mailed to accounting graduates who graduated from Fall 1999 to Spring 2002 was used to gather the data for the study. Responses from graduates with different curricular paths were compared to determine if significant differences existed in their perceptions of the development of their personal competencies. Results revealed that no significant difference exists in the perception of the development of personal competencies among …
Development Of Dynamic Travel Demand Models For Hurricane Evacuation, Haoqiang Fu
Development Of Dynamic Travel Demand Models For Hurricane Evacuation, Haoqiang Fu
LSU Doctoral Dissertations
Little attention has been given to estimating dynamic travel demand in transportation planning in the past. However, when factors influencing travel are changing significantly over time – such as with an approaching hurricane - dynamic demand and the resulting variation in traffic flow on the network become important. In this study, dynamic travel demand models for hurricane evacuation were developed with two methodologies: survival analysis and sequential choice model. Using survival analysis, the time before evacuation from a pending hurricane is modeled with those that do not evacuate considered as censored observations. A Cox proportional hazards regression model with time-dependent …
Analysis Of Bacterial Diversity And Biogeography At The Central Arizona-Phoenix Long Term Ecological Research (Cap Lter) Site, Brian Anthony Rash
Analysis Of Bacterial Diversity And Biogeography At The Central Arizona-Phoenix Long Term Ecological Research (Cap Lter) Site, Brian Anthony Rash
LSU Doctoral Dissertations
The limiting factor involved in past assessments of soil bacterial diversity when using culture-independent techniques has often been the lack of sampling and replication. As a result, analyses of community structural shifts across soil environments have lacked statistical power. In this study, 23 16S rRNA gene clone libraries consisting of over 11,000 clones were constructed from soils at the Central Arizona Phoenix Long Term Ecological Research (CAP LTER) site. Subsequent ARDRA fingerprinting and partial 16S rRNA gene sequencing allowed for a more robust investigation of various components that may explain any observed variations in bacterial species composition. The designated land …
The Influence Of State Merit-Based Aid On Access And Educational Experiences: An Exploration Of The Louisiana Tuition Opportunity Program For Students (Tops), Roderick L. Smothers
The Influence Of State Merit-Based Aid On Access And Educational Experiences: An Exploration Of The Louisiana Tuition Opportunity Program For Students (Tops), Roderick L. Smothers
LSU Doctoral Dissertations
Access to higher education at the beginning of the new millennium faces unprecedented challenges. Although many of those challenges have been identified and addressed through research and federal and state policies, there still exists an inherent gap in the current and potential future success of today’s college students. This is particularly true for minority and lower-income students. Some of the identified challenges include: lack of financial assistance, persisting through and graduating from college, pre-college preparation, socioeconomic status, and family support/motivation. This study focuses primarily on the financial barriers that impede the process of providing equal access to all students, which …
Optimization Of A Skewed Logistic Distribution With Respect To The Kolmogorov-Smirnov Test, James Charles Finney
Optimization Of A Skewed Logistic Distribution With Respect To The Kolmogorov-Smirnov Test, James Charles Finney
LSU Doctoral Dissertations
The four-parameter kappa distribution (Hosking 1994) was analyzed with respect to the various possible shapes of the probability density function. The general form for the cumulative distribution function when both h and k are non-zero is: F(x) = { 1 - h [ 1 - k ( x - ξ ) / α ]1/k }1/h. The parameters h and k work together to define the function's shape, ξ affects location, and α is the scale parameter. A method of selecting parameters to minimize the Kolmogorov-Smirnov test statistic, D, was developed. The technique was first described for the …
Foreland Basins: Lithospheric Flexure, Plate Strength And Regional Stratigraphy, John Londono
Foreland Basins: Lithospheric Flexure, Plate Strength And Regional Stratigraphy, John Londono
LSU Doctoral Dissertations
Foreland basin subsidence through time is reproduced in this study, as the flexure of an elastic beam in an inviscid fluid under the vertical stress, caused by discrete-distributed loads. Thus, seismostratigraphic data from the Timor Sea peripheral foreland basin, in northwestern Australia, and the Putumayo retroarc foreland basin in the Colombian Andes, are forward modeled, at chronostratigraphic intervals, to assess the evolving geodynamic conditions of the basins. Results show that the accommodation in foreland basins varies as the depositional basement is vertically adjusted according to the regionally isostatic compensation of the lithosphere. Distributed tectonic (thrust belts) and sedimentary loads that …
Applications Of The Titanium Catalyzed Cyclocarbonylation Towards Natural Product Syntheses, Jongtae Yang
Applications Of The Titanium Catalyzed Cyclocarbonylation Towards Natural Product Syntheses, Jongtae Yang
LSU Doctoral Dissertations
Recently an efficient methodology, a hetero Pauson-Khand reaction, based on titanium-catalyzed cyclocarbonylation of tethered enals for the general preparation of ¥ã-butyrolactone rings, which are typically embedded in polycyclic systems of many natural products was reported. To demonstrate this new strategy, the total syntheses of the natural products asteriscanolide and ginkgolide were investigated. The first part of this work is dedicated to synthetic efforts toward the total synthesis of asteriscanolide. Approaches highlighted by the [2,3]-Wittig rearrangement, the thermal silyloxy-Cope rearrangement, and a titanium-catalyzed cyclocarbonylation, which is the pivotal step to afford the ¥ã-butyrolactone ring. This study firmly established the utility of …
Ceria-Zirconia Oxide High Temperature Desulfurization Sorbent, Kwang Bok Yi
Ceria-Zirconia Oxide High Temperature Desulfurization Sorbent, Kwang Bok Yi
LSU Doctoral Dissertations
High temperature desulfurization of highly reducing coal-derived gases using ceria and ceria-zirconia sorbents is the primary object of this dissertation research. If H2S concentration is reduced to less than 1 ppmv the product gas may be used with fuel cells and downstream catalytic process. CeO2 is reduced to a non-stoichiometric oxide, which is superior to CeO2 in removing H2S. Moreover, ZrO2 addition to CeO2 to form a solid solution, Ce1-xZrxO2, increases the reducibility of CeO2. This should also result in improved desulfurization performance. Pure CeO2 and sorbents, both commercially available and prepared at LSU, were tested. XRD analysis indicated that …
The Significance Of Selected Piano Compositions By Pancho Vladigerov, Boriana Kojouharova Buckles
The Significance Of Selected Piano Compositions By Pancho Vladigerov, Boriana Kojouharova Buckles
LSU Doctoral Dissertations
This study examines selected compositions for piano by Pancho Vladigerov - the Three Pieces for Piano, Opus 15, Bulgarian Rhapsody, Opus 16, Shumen Miniatures, Opus 29, and Improvisation and Toccata, from Episodes, Opus 36. These pieces strongly represent the various periods and stylistic trends of the composer. They are also among Vladigerov's most popular and frequently performed piano compositions. The first chapter provides a brief biography of Pancho Vladigerov and an overview of his most important compositions. Chapter Two contains an overview of the solo piano works of Vladigerov. Chapter Three examines the selected piano compositions from a formal and …
Influence Of The Marsh Edge On The Structure And Trophic Ecology Of The Fish And Macroinvertebrate Community In A Louisiana Estuarine Ecosystem, Guillermo Duque
Influence Of The Marsh Edge On The Structure And Trophic Ecology Of The Fish And Macroinvertebrate Community In A Louisiana Estuarine Ecosystem, Guillermo Duque
LSU Doctoral Dissertations
Habitat degradation of saltmarsh ecosystems reduces the suitability of the marsh as permanent environments for resident species and seasonal nursery grounds for transient fauna. This study was conducted in Terrebonne-Timbalier bays near Cocodrie, Louisiana. Fishes and macroinvertebrates were collected using a drop sampler in marsh-edge and open-water habitat types, in three locations (i.e., pond, channel, and bay), and four seasons (Fall of 2000, Winter of 2000-2001, and Spring and Summer of 2001). The specific objectives of this study were: (1) to determine the difference in composition and structure of fish and macroinvertebrate communities, (2) to establish the food habits of …
William Faulkner And The Oral Text, Gregory Alan Borse
William Faulkner And The Oral Text, Gregory Alan Borse
LSU Doctoral Dissertations
The disjunction between the oral and the literate in the works of William Faulkner reveals the different ways these distinct modes of organization combine to structure a text. The oral in Faulkner's fiction makes its presence known not only as offset speech but also as a mode of action and narrative whose logic is conjunctive rather than disjunctive. According to the literate mode, a form organizes novelistic matter. According to the oral mode, forces that function as signs rather than organizers of their form rule the action and narrative. When the disjunction between the oral and the literate is so …
Small And Large Strain Monitoring Of Unsaturated Soil Behavior By Means Of Multiaxial Testing And Shear Wave Propagation, Oscar F. Porras Ortiz
Small And Large Strain Monitoring Of Unsaturated Soil Behavior By Means Of Multiaxial Testing And Shear Wave Propagation, Oscar F. Porras Ortiz
LSU Doctoral Dissertations
The deformation and strength behavior of dry and saturated soils is controlled by the effective stresses as defined by Terzaghi. However, Terzaghi’s definition of the effective stresses fails for unsaturated soils, as capillarity force influence is also important. The effects of capillarity forces in soil are evaluated by the concept of matrix suction. Several techniques are used to evaluate soil suction however their applications involve difficult calibrations and tedious methodology. Furthermore, suction is a microscopic property and it is influenced by interparticle soil attraction, which can change by sampling disturbance. This research program evaluates the effect of suction on stiffness …
Design And Operating Strategies For Bioreactors Treating Dynamically Varying Concentrations Of Gas-Phase Volatile Organic Compounds (Vocs), Congna Li
LSU Doctoral Dissertations
The dynamically varying concentrations of volatile organic compounds (VOCs) in most waste gas streams present a challenge in design and operation of biofilters treating such off-gases. Studies described in this dissertation were directed toward development and experimental testing of two design modifications/operating strategies that have the potential to improve biofilter performance during unsteady-state loadings. In the first design modification studied, activated carbon was incorporated into biofilter packing media and a novel periodic operating strategy, Sequencing Batch Biofilter (SBB) operation, was tested under “normal” and various “shock” loading conditions treating methyl ethyl ketone contaminated air. Results demonstrate how the operational flexibility …
Cost Effective And Sequential Methods For Teaching Educational Paraprofessionals To Implement Behavior Management Strategies In Preschool Classrooms, Natalie Jan Slider
Cost Effective And Sequential Methods For Teaching Educational Paraprofessionals To Implement Behavior Management Strategies In Preschool Classrooms, Natalie Jan Slider
LSU Doctoral Dissertations
This study examined the efficacy of cost effective and sequential training methods for teaching educational paraprofessionals to implement behavior management strategies in preschool classrooms. Investigation of the effects of increasingly complex and time consuming methods of training on both paraprofessional and student behaviors were evaluated. Training methods employed included written take-home manuals and summary cards, modeling videotapes, and performance feedback. Training materials included three behavior management strategies (e.g., instruction-giving, praise, and time out) that have shown to have extensive support in the empirical literature (Brophy, 1981; Budd, Riner, & Brockman, 1983; Flanagan, Adams, & Forehand, 1979; O’Dell, Krug, Patterson, & …
Spatial Econometric Analysis Of Louisiana Rural Real Estate Values, Patricia Soto
Spatial Econometric Analysis Of Louisiana Rural Real Estate Values, Patricia Soto
LSU Doctoral Dissertations
The general purpose of this study was to conduct a spatial analysis of the dynamics of rural land values in Louisiana. Specifically, spatial econometric procedures and hedonic price analysis were used to evaluate the impact of land characteristics on land prices across rural land markets in Louisiana. Initially, hedonic models were estimated by ordinary least squares (OLS) procedures to test for the presence of spatial autocorrelation using Lagrange Multiplier tests. Results suggested that there was spatial autocorrelation in the error terms. Hedonic models were then estimated using maximum likelihood (ML) spatial error techniques. Log likelihood numbers and likelihood ratio tests …
A Basic Interpretative Analysis Of Instrumental Music Education Majors' Approaches To Score Study In Varying Musical Contexts, Jeremy S. Lane
A Basic Interpretative Analysis Of Instrumental Music Education Majors' Approaches To Score Study In Varying Musical Contexts, Jeremy S. Lane
LSU Doctoral Dissertations
The purposes of this qualitative study were to 1) provide a holistic description of procedures used by undergraduate instrumental music education majors (N = 21) in music score study tasks; 2) examine relationships among these procedures and their use in varying musical contexts; 3) examine relationships among score study tendencies, education level, and overall musical ability; and 4) provide general comparisons of undergraduate music education majors’ score study procedures and those implied by expert conductors’ major disciplinary ways of thinking. Each subject participated in two one-on-one interview sessions with the investigator. During each session, subjects “thought out loud” as they …
Internal Revenue Service Restructuring And Reform Act Of 1998: A Test Of New Public Management, William Meriwether Vandenburgh
Internal Revenue Service Restructuring And Reform Act Of 1998: A Test Of New Public Management, William Meriwether Vandenburgh
LSU Doctoral Dissertations
The enactment of the 1998 Internal Revenue Service (IRS) Reform Act resulted directly from perceived lapses in the federal taxation administration, which was publicly highlighted in Congressional hearings. Congress reacted by fundamentally altering the IRS’s implementation of the Internal Revenue Code (for the first time since 1952). The Joint Committee on Taxation noted that the overall objective of the 1998 IRS Reform Act was to have “a well-run IRS [which] is critical to the operation of our tax system.” From a public administration paradigm, the IRS moved from a traditional tax management methodology to a New Public Management (NPM) methodology. …
Transfer Functions Of Streptomyces Plasmid Pij101: Insights Into A Novel Bacterial Conjugation System, Matthew John Ducote
Transfer Functions Of Streptomyces Plasmid Pij101: Insights Into A Novel Bacterial Conjugation System, Matthew John Ducote
LSU Doctoral Dissertations
For Streptomyces plasmid pIJ101 to mediate DNA transfer, only the clt locus and the Tra protein are required, though three non-essential spread functions increase the radial distance of plasmid dissemination among recipients after the initial lateral transfer event. clt is a contiguous 54-bp sequence within an intrinsically curved plasmid region that contains inverted and direct repeats; biochemical and genetic methods described here indicate that single-stranded cleavage reminiscent of most conjugative plasmids does not occur at clt. clt therefore likely promotes plasmid transfer by interacting with the pIJ101 Tra protein or host-encoded factors in a transient, novel DNA-processing event or by …
Flesh And Spirit Onstage: Chronotopes Of Performance In Medieval English Theatre, Gregory Lee Cavenaugh
Flesh And Spirit Onstage: Chronotopes Of Performance In Medieval English Theatre, Gregory Lee Cavenaugh
LSU Doctoral Dissertations
This study uses Mikhail Bakhtin's chronotope, which is the informing principle of one's experience of space and time, to explore different relations among space, time, actors, and audience in medieval theatre. Relations between the material and spiritual worlds as understood in the Middle Ages are considered in the context of relations between performers and audience members with two goals. First, I explore how the ontological status of the metaworld created through performance changed in the context of specific chronotopes. Second, I explore how diverse religious discourses affected medieval modes of representation. This study posits three chronotopes of performance informing medieval …
A Theory Of Effective Computer-Based Instruction For Adults, Janis Sue Lowe
A Theory Of Effective Computer-Based Instruction For Adults, Janis Sue Lowe
LSU Doctoral Dissertations
Computer-based instruction (CBI) was considered the technological phenomenon to revolutionize education and training. Today, the Internet and computer technology are reported to have significantly altered the education landscape (Johnson & Aragon, 2002). The rapid advances in technology, the need for lifelong learning, and the growth of non-traditional students have encouraged the use of the computer as a method of instructional delivery. Evaluating the effectiveness of CBI as a whole technology is very difficult. The inability to measure effectiveness is attributable in part to the fact that CBI is not just one component, but a complex range of services and activities …
Modeling Event-Based Coupled Hydrologic And Mass Transport In Small Urban Watersheds, Yuhong Sheng
Modeling Event-Based Coupled Hydrologic And Mass Transport In Small Urban Watersheds, Yuhong Sheng
LSU Doctoral Dissertations
To investigate the event-based coupled hydrologic and mass transport processes of particulate matter and their eventual fate in unit operations/processes, several methodologies were developed. Discrete rainfall-runoff events data were collected at two similar urban watersheds for model calibration and verification. A mathematically and physically-based criterion was proposed to differentiate rainfall-runoff events between either mass-limited or flow-limited. Statistical techniques of Logistic Regression and Discriminant Analysis were utilized to derive classification rules for event categories based on hydrologic data only. With watersheds assumed as either lumped systems or distributed systems, physically-based semi-empirical models were developed to simulate particulate mass delivery process during …
The Spectral Conforming Model And Its Applications, Jaeho Shim
The Spectral Conforming Model And Its Applications, Jaeho Shim
LSU Doctoral Dissertations
It has been observed that finite element or finite difference model of order can approximate with fair accuracy less than one-third of the eigenvalues of the underlying continuous system corresponding to the low spectrum. The new discrete model, namely the spectral conforming model, is developed to predict the eigenvalues of continuous systems in both the low and high spectra. The spectral conforming models are developed using an inverse vibration method. The classical vibration problem is the direct method. In the direct approach, the characteristic behaviors of the system, i.e. frequency response, natural frequency, and steady state response are analyzed and …
A New Broad Spectrum Disinfectant Suitable For The Food Industry, Giovanna Aita Dequeiroz
A New Broad Spectrum Disinfectant Suitable For The Food Industry, Giovanna Aita Dequeiroz
LSU Doctoral Dissertations
A unique biocide composition (patent pending) that is formed from a hydrogen peroxide and sodium hypochlorite mixture was investigated. A biocidal "complex" is formed by adding the peroxide to the hypochlorite in an amount so that the weight ratio of the peroxide to the hypochlorite is no less than 1:10. The chemical structure of this biocidal "complex" is uncertain but we postulate that it is a semi-stable complex, whose stability is disrupted by heat, acid, U/V exposure and the presence of organic matter (i.e., microbes) The antimicrobial activity of the biocidal "complex" is most likely a combination effect between oxidation …
Routes Of Freedom: Slave Resistance And The Politics Of Literary Geography, Judith Louise Kemerait
Routes Of Freedom: Slave Resistance And The Politics Of Literary Geography, Judith Louise Kemerait
LSU Doctoral Dissertations
This dissertation integrates rhetorical, historical, and spatial analysis in an effort to expand our understanding of the cultural work performed by antebellum narratives that take slavery in the United States as their subject matter. Specifically, it focuses on the complicated relationship between place and human praxis as revealed in five texts: The Confessions of Nat Turner, Harriet Beecher Stowe’s Dred, Martin R. Delany’s Blake, Frederick Douglass’s “The Heroic Slave,” and Herman Melville’s Benito Cereno. In my attention to literary geographies, I trace spatial patterns in which considerations of organized resistance and slave rebellion are repeatedly placed in “wild-spaces” such as …
The Effect Of Program Commitment On The Degree Of Participative Congruence And Managerial Performance In A Budgeting Setting, Kevin T. Breaux
The Effect Of Program Commitment On The Degree Of Participative Congruence And Managerial Performance In A Budgeting Setting, Kevin T. Breaux
LSU Doctoral Dissertations
The purpose of this research endeavor is to investigate the effect that the degree of participative congruence has on the relationship between program commitment and managerial performance. The degree of participative congruence (Clinton and Hunton 2001) is a new measure of participation designed to determine the amount of congruence between the perceived need for participation and the degree of participation allowed. This study used a questionnaire to evaluate the antecedents of and effects of the degree of participative congruence (DPC) in a budgeting setting. In order to investigate these effects, the questionnaire was mailed to a sample of 1,500 AICPA …
Leaf Litter Processing By Macrodetritivores In Natural And Restored Neotropical Mangrove Forests, Gary Eugene Raulerson
Leaf Litter Processing By Macrodetritivores In Natural And Restored Neotropical Mangrove Forests, Gary Eugene Raulerson
LSU Doctoral Dissertations
Knowledge of mangrove litter dynamics is crucial to an understanding of the energetic links between mangrove ecosystems and nearby estuaries and coastal waters. Previous research into the role played by macrodetritivores in Neotropical mangrove litter processing has been contradictory. This study used leaf tethering to examine the effects of macrodetritivores on initial rates of mangrove litter degradation in South Florida, USA. Leaf litter dynamics experiments were run in both natural and restored mangrove forests to assess functionality of the restoration projects. Although less important than in some other parts of the world (e.g., the Indo-Pacific), macrodetritivores played a significant role …
Dynamic Performance Of Bridges And Vehicles Under Strong Wind, Suren Chen
Dynamic Performance Of Bridges And Vehicles Under Strong Wind, Suren Chen
LSU Doctoral Dissertations
The record of span length for flexible bridges has been broken with the development of modern materials and construction techniques. With the increase of bridge span, the dynamic response of the bridge becomes more significant under external wind action and traffic loads. The present research targets specifically on dynamic performance of bridges as well as the transportation under strong wind. The dissertation studied the coupled vibration features of bridges under strong wind. The current research proposed the modal coupling assessment technique for bridges. A closed-form spectral solution and a practical methodology are provided to predict coupled multimode vibration without actually …
A National Set Of Competencies For Paraprofessionals In Residential College Or Living/Learning Programs, Debora Elise Baker
A National Set Of Competencies For Paraprofessionals In Residential College Or Living/Learning Programs, Debora Elise Baker
LSU Doctoral Dissertations
A competency model, for supporting student learning, was developed for the paraprofessional position (R.A., Community Assistant, etc.) in residential college or living/learning programs. The researcher developed the model through a two-stage process. In the first stage, the critical incident technique was applied utilizing the experiences of paraprofessionals at 15 different universities to develop an initial set of competencies and related tasks. In the second stage, the Delphi Technique was used to allow faculty and staff from 17 universities to refine and validate the competencies and related tasks. The final competency model includes twelve competencies related to linking hall community programs …
Modeling The Hydrologic And Particulate Loadings From Paved Urban Surfaces, Chad Michael Cristina
Modeling The Hydrologic And Particulate Loadings From Paved Urban Surfaces, Chad Michael Cristina
LSU Doctoral Dissertations
This dissertation details the results of recent investigations concerning non-colloidal particulate matter found in urban rainfall-runoff and urban snowmelt. Three forms of the power law model (PLM) were used to model particle number density. It was found that significant model error could be introduced into PLMs when the median diameter particle was used to estimate the number of particles per interval, but the SSE of continuous PLMs could be significantly reduced through the use of correction factors when the sieve interval was large (P<0.05). Additionally, a multiple PLM analysis may be more appropriate than a single PLM analysis when changes in particle population occur within a single gradation. PLMs were also used to model the relationship between cumulative granulometric mass and cumulative particulate-bound metal mass. The use of such calibrated PLMs provided considerable cost reduction when compared to conventional direct measurements of particulate-bound metal mass. A first flush analysis indicated that only events with average volumetric flow rates approaching 1 L/min/m of drainage width exhibit a rapid depletion of particulate matter consistent with the concentration-based definition of the first flush. An analysis of particle separation mechanisms indicated that 90% of these particles, by mass, could be removed from the discharge with detention times of 30 min and 120 min for snowmelt and rainfall-runoff, respectively, in a typical roadside drainage system. It was also found that the kinematic wave model could accurately model significant aspects of rainfall-runoff events in traffic-impacted watersheds provided that abstractions were incorporated into the modeling process. For this watershed the source of abstraction was attributable to vehicular traffic. For high-intensity events with more than 10 vehicles per runoff volume (VPV) the runoff coefficient varied between 0.6 and 0.9 while for low-intensity events with fewer than 10 VPV the coefficient ranged between 0.2 and 0.4.