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Relationships Among Self-esteem, Psychological and Cognitive Flexibility, and Psychological Symptomatology

Description: Previous findings on the relationship between self-esteem and psychological outcomes are inconsistent. Therefore it appears that self-esteem, while related to crucial variables, does not provide a clear, direct, and comprehensive prediction of psychological symptoms. Thus, it was hypothesized that the relationship between self-esteem and symptomatology would be moderated by broader measures of how one interacts with emotional and cognitive stimuli.The purpose of this study was to examine the influence of self-esteem, psychological flexibility, and cognitive flexibility on psychological symptomatology. A sample of 82 undergraduate students at the University of North Texas completed self-report questionnaires measuring low self-esteem, psychological flexibility, measured inversely as inflexibility, cognitive flexibility, and psychological symptoms. Results of the study suggest that self-esteem (?= -0.59, p < 0.001) and flexibility (both psychological (?= 0.36, p = 0.001) and cognitive (?= 0.21, p < 0.05) are significant predictors of psychological symptoms. In other words, self-esteem is positively correlated with psychological symptoms, while psychological and cognitive flexibility are negatively correlated with psychological symptoms. Neither form of flexibility moderated the relationship between self-esteem and psychological symptoms in this sample. The findings of the current study are discussed as well as suggestions for further research related to self-esteem, psychological and cognitive flexibility, and their impact on psychological outcomes.
Date: December 2012
Creator: Al-Jabari, Rawya, M.
Partner: UNT Libraries

Influence of wing flexibility on force-time relation in shock strut following vertical landing impact

Description: Report presenting testing to determine the force developed in a shock strut as a function of the flexibility of the attached wing structure. Both the experiment and analysis indicated that wing flexibility had some effect on the shape and peak value of the force-time curve in a shock strut.
Date: November 1949
Creator: McPherson, Albert E.; Evans, J., Jr. & Levy, Samuel
Partner: UNT Libraries Government Documents Department

The flexible rectangular wing in roll at supersonic flight speeds

Description: From Summary: "The problem of the loss in rolling effectiveness at supersonic flight speeds is considered for the case of the rectangular wing. Equations are obtained from which can be calculated either the loss in rate of roll due to flexibility or the torsional stiffness required to maintain a given rate of roll, for two assumed variations of the spanwise distribution of torsional stiffness. A computation form and figures are provided so that calculations can be made without reference to the details of the analysis."
Date: December 1948
Creator: Tucker, Warren A. & Nelson, Robert L.
Partner: UNT Libraries Government Documents Department

The effect of torsional flexibility on the rolling characteristics at supersonic speeds of tapered unswept wings

Description: From Summary: "An analysis is presented of the effect of torsional flexibility on the rolling characteristics at supersonic speeds of tapered unswept wings with partial-span constant-percent-chord ailerons extending inboard from the wing tip. The geometric variables considered are aspect ratio, taper ratio, aileron span, and aileron chord. The shape of the wing-torsional-stiffness curve is assumed and the twisting moment is considered to result solely from the pressure distribution caused by aileron deflection, so that the necessity of using a successive-approximation method is avoided."
Date: March 8, 1949
Creator: Tucker, Warren A. & Nelson, Robert L.
Partner: UNT Libraries Government Documents Department

A correlation of results of flight investigation with results of an analytical study of effects of wing flexibility on wing strains due to gusts

Description: An analytical study of the effects of wing flexibility on wing strains due to gusts has been made for four spanwise stations of a four-engine bomber airplane, and the results have been correlated with results of a previous flight investigation.
Date: 1958
Creator: Shufflebarger, C. C.; Payne, Chester B. & Cahen, George L.
Partner: UNT Libraries Government Documents Department

Hydrodynamic impact of a system with a single elastic mode 2: comparison of experimental force and response with theory

Description: From Summary: "Hydrodynamic impact tests were made on an elastic model approximating a two-mass spring system to determine experimentally the effects of structural flexibility on the hydrodynamic loads encountered during seaplane landing impacts and to correlate the results with theory. A flexible seaplane was represented by a two-mass spring system consisting of a rigid prismatic float connected to a rigid upper mass by an elastic structure. The model had a ratio of sprung mass to hull mass of 0.6 and a natural frequency of 3.0 cycles per second. The tests were conducted in smooth water at fixed trims and included both high and low flight-path angles and a range of velocity. Theoretical and experimental comparisons indicated that the theoretical results agreed well with the experimental results."
Date: January 30, 1951
Creator: Miller, Robert W. & Merten, Kenneth F.
Partner: UNT Libraries Government Documents Department

The effects of flexibility on the longitudinal and lateral directional response of a large airplane

Description: Report presenting longitudinal and lateral-directional frequency responses determined from transient flight data excited by control pulses for a large flexible swept-wing airplane over a wide range of flight conditions. The effects of structural modes on the frequency response at various locations on the airplane are shown. Results regarding the low-frequency response, longitudinal transfer-function coefficients, lateral response, lateral-directional transfer-function coefficients, experimental technique, and high-frequency responses are provided.
Date: May 27, 1955
Creator: Cole, Henry A., Jr.; Brown, Stuart C. & Holleman, Euclid C.
Partner: UNT Libraries Government Documents Department

A comparison of theoretical and experimental wing bending moments during seaplane landings

Description: Report presenting a smooth-water-landing investigation with a small seaplane to obtain experimental wing-bending-moment time histories together with time histories of the various parameters necessary for the prediction of wing bending moments during hydrodynamic impact. Experimental results were compared with calculated results, including inertia-load effects and the effects of air-load variation during impact.
Date: April 1950
Creator: Merten, Kenneth F.; RodrÍguez, José L. & Beck, Edgar B.
Partner: UNT Libraries Government Documents Department

Integration of Phenotypic Metadata and Protein Similarity in Archaea Using a Spectral Bipartitioning Approach

Description: In order to simplify and meaningfully categorize large sets of protein sequence data, it is commonplace to cluster proteins based on the similarity of those sequences. However, it quickly becomes clear that the sequence flexibility allowed a given protein varies significantly among different protein families. The degree to which sequences are conserved not only differs for each protein family, but also is affected by the phylogenetic divergence of the source organisms. Clustering techniques that use similarity thresholds for protein families do not always allow for these variations and thus cannot be confidently used for applications such as automated annotation and phylogenetic profiling. In this work, we applied a spectral bipartitioning technique to all proteins from 53 archaeal genomes. Comparisons between different taxonomic levels allowed us to study the effects of phylogenetic distances on cluster structure. Likewise, by associating functional annotations and phenotypic metadata with each protein, we could compare our protein similarity clusters with both protein function and associated phenotype. Our clusters can be analyzed graphically and interactively online.
Date: January 1, 2009
Creator: Hooper, Sean D.; Anderson, Iain J; Pati, Amrita; Dalevi, Daniel; Mavromatis, Konstantinos & Kyrpides, Nikos C
Partner: UNT Libraries Government Documents Department

A correlation of results of a flight investigation with results of an analytical study of effects of wing flexibility on wing strains due to gusts

Description: Report presenting a study of the effects of wing flexibility on wing strains due to gusts for four spanwise stations of a four-engine bomber airplane and a correlation with previous testing results. Results regarding the power spectre, peak counts, amplification factors, statistical reliability, input disturbance, frequency-response functions, output response, and amplification factors are provided.
Date: August 1957
Creator: Shufflebarger, C. C.; Payne, Chester B. & Cahen, George L.
Partner: UNT Libraries Government Documents Department

Goddard rattler-jamming mechanism for quantifying pressure dependence of elastic moduli of grain packs

Description: An analysis is presented to show how it is possible for unconsolidated granular packings to obey overall non-Hertzian pressure dependence due to the imperfect and random spatial arrangements of the grains in these packs. With imperfect arrangement, some gaps that remain between grains can be closed by strains applied to the grain packing. As these gaps are closed, former rattler grains become jammed and new stress-bearing contacts are created that increase the elastic stiffness of the packing. By allowing for such a mechanism, detailed analytical expressions are obtained for increases in bulk modulus of a random packing of grains with increasing stress and strain. Only isotropic stress and strain are considered in this analysis. The model is shown to give a favorable fit to laboratory data on variations in bulk modulus due to variations in applied pressure for bead packs.
Date: January 5, 2009
Creator: Pride, Steven R. & Berryman, James G.
Partner: UNT Libraries Government Documents Department

Progress update on the US photovoltaic manufacturing technology project

Description: The Photovoltaic Manufacturing Technology (PVMaT) project is helping the U.S. photovoltaic (PV) industry extend its world leadership role in manufacturing and stimulate the commercial development of PV modules and systems. Initiated in 1990, PVMaT is being carried out in several directed and staggered phases to support industry`s continued progress. Thirteen subcontracts awarded in FY 1996 under Phase 4A emphasize improvement and cost reduction in the manufacture of full-system PV products. Areas of work in Phase 4A included, but were not limited to, issues such as improving module-manufacturing processes; system and system-component packaging, integration, manufacturing, and assembly; product manufacturing flexibility; and balance-of-system development with the goal of product manufacturing improvements. These Phase 4A, product-driven manufacturing research and development (R&amp;D) activities are now completing their second phase. Progress under these Phase 4A and remaining Phase 2B subc ontracts from the earlier PVMaT solicitation are summarized in this paper. Evaluations of the success of this project have been carried out in FY 1995 and late FY 1996. This paper examines the 1997 cost/capacity data that have been collected from active PVMaT manufacturers.
Date: October 1, 1997
Creator: Mitchell, R.L.; Witt, C.E. & Thomas, H.P.
Partner: UNT Libraries Government Documents Department

An overview of the NREL/SNL flexible turbine characterization project

Description: There has been a desire to increase the generating capacity of the latest generation of wind turbine designs. In order to achieve these larger capacities, the dimensions of the turbine rotors are also increasing significantly. These larger structures are often much more flexible than their smaller predecessors. This higher degree of structural flexibility has placed increased demands on available analytical models to accurately predict the dynamic response to turbulence excitation, In this paper we present an overview and our progress to date of a joint effort of the National Renewable Energy Laboratory (NREL) and the Sandia National Laboratory (SNL). In this paper we present an overview and status of an ongoing program to characterize and analytically model the dynamics associated with the operation of one of the most flexible turbine designs currently available, the Cannon Wind Eagle 300 (CWE-300). The effort includes extensive measurements involving a detailed inventory of the turbine's physical properties, establishing the turbine component and fill-system vibrational modes, and documenting the dynamic deformations of the rotor system and support tower while in operation.
Date: September 1, 1998
Creator: Bir, Gunjit; Kelley, Neil; McKenna, Ed; Osgood, Richard; Sutherland, Herbert & Wright, Alan
Partner: UNT Libraries Government Documents Department

Standardized approach for developing probabilistic exposure factor distributions

Description: The effectiveness of a probabilistic risk assessment (PRA) depends critically on the quality of input information that is available to the risk assessor and specifically on the probabilistic exposure factor distributions that are developed and used in the exposure and risk models. Deriving probabilistic distributions for model inputs can be time consuming and subjective. The absence of a standard approach for developing these distributions can result in PRAs that are inconsistent and difficult to review by regulatory agencies. We present an approach that reduces subjectivity in the distribution development process without limiting the flexibility needed to prepare relevant PRAs. The approach requires two steps. First, we analyze data pooled at a population scale to (1) identify the most robust demographic variables within the population for a given exposure factor, (2) partition the population data into subsets based on these variables, and (3) construct archetypal distributions for each subpopulation. Second, we sample from these archetypal distributions according to site- or scenario-specific conditions to simulate exposure factor values and use these values to construct the scenario-specific input distribution. It is envisaged that the archetypal distributions from step 1 will be generally applicable so risk assessors will not have to repeatedly collect and analyze raw data for each new assessment. We demonstrate the approach for two commonly used exposure factors--body weight (BW) and exposure duration (ED)--using data for the U.S. population. For these factors we provide a first set of subpopulation based archetypal distributions along with methodology for using these distributions to construct relevant scenario-specific probabilistic exposure factor distributions.
Date: March 2003
Creator: Maddalena, Randy L.; McKone, Thomas E. & Sohn, Michael D.
Partner: UNT Libraries Government Documents Department

Flight investigation of the effect of transient wing response on wing strains of a four-engine bomber airplane in rough air

Description: Report presenting a flight investigation on a four-engine bomber airplane to determine the effects of wing flexibility on wing strains developed in flight through clear-air turbulence. Amplification of the effects appeared to be a function of gust-gradient distance and was not significantly affected by airspeed or weight.
Date: June 1953
Creator: Murrow, Harold N. & Payne, Chester B.
Partner: UNT Libraries Government Documents Department

Elastic buckling under combined stresses of flat plates with integral waffle-like stiffening

Description: Theory and experiment were compared and found in good agreement for the elastic buckling under combined stresses of long flat plates with integral waffle-like stiffening in a variety of configurations. For such flat plates, 45 degree waffle stiffening was found to be the most effective of the configurations for the proportions considered over the widest range of combinations of compression and shear.
Date: January 1954
Creator: Dow, Norris F.; Levin, L. Ross & Troutman, John L.
Partner: UNT Libraries Government Documents Department

Effects of airplane flexibility on wing strains in rough air at 5,000 feet as determined by flight tests of a large swept-wing airplane

Description: Report presenting a flight investigation of a large swept-wing bomber airplane in rough air at 5,000 feet to determine the effects of wing flexibility on wing bending and shear strains. Aeroelastic effects were found to be large, particularly at the outboard measuring stations. Results regarding the bending strains and shear strains are provided.
Date: September 1957
Creator: Rhyne, Richard H. & Murrow, Harold N.
Partner: UNT Libraries Government Documents Department

The Relative Contribution of Flexibility of the Back and Hamstring Muscles in the Performance of the Sit and Reach Component of the AAHPERD Health Related Fitness Test in Girls Thirteen to Fifteen Years of Age

Description: The purpose of the study was to quantify the relative contribution of low back flexibility and hamstring flexibility in the sit and reach test item of the AAHPERD Health Related Fitness Test in order to examine the validity of the sit and reach test. Subjects were 100 female students, 13 to 15 years of age in physical education classes. Hamstring flexibility was measured using the Leighton flexometer. Spinal mobility was measured using a tape measure. The sit and reach test was performed according to instructions given in the AAHPERD Test Manual. Data were analyzed using correlation, linear regression, and multiple regression. Conclusions of the investigation were (1) hamstring flexibility is moderately related to the sit and reach test, (2) low back flexibility has a very small relationship to the sit and reach test, and (3) the sit and reach test is an inadequate measure of low back and hamstring flexibility.
Date: August 1985
Creator: Baker, Alice Ann
Partner: UNT Libraries

The Relationship of the Sit and Reach Test to Criterion Measures of Hamstring and Back Flexibility in Adult Males and Females

Description: The purpose of this study was to examine the criterion-related validity of the sit and reach test as a measure of hamstring and low back flexibility in adult males and females. Subjects were 52 males and 52 females, 20 to 45 years of age. Hamstring flexibility was measured using a goniometer. Spinal flexibility was measured using a tape measure and an inclinometer. The sit and reach test was performed according to the AAHPERD Health Related Fitness Test Manual. Data were analyzed using correlations and appropriate descriptive statistics. Conclusions of the investigation were: 1) in adult males 20 to 45, the sit and reach test is a valid measure of hamstring flexibility but has questionable validity as a measure of low back flexibility, 2) in adult females 20 to 45, the sit and reach test is a moderately valid measure of hamstring flexibility and is not a valid measure of low back flexibility.
Date: August 1987
Creator: Langford, Nancy Jane
Partner: UNT Libraries