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Use of Analog Computers for Simulating the Movement of Isotopes in Ecological Systems
No Description Available.
Diffusion of Slow Electrons in Gases
The properties of electrons in a gas and an external electric field, e.g., agitation velocity, free path, energy lost per collision, and collision cross sections, were determined for electrons of energy less than 2 ev in a large number of gases. The computations were made from previously measured values for Townsend's energy factor or the ratio of electron agitation energy to molecule thermal energy. Results are presented for hydrogen, nitrogen, carbon dioxide, methane, ethylene, cyclopropane, and argon. (D.L.C.)
A Study of the Kinetic and Mechanical Properties of a Stabilized Beta Phase Plutonium Alloy
The elements Sn, Mg, Ti, Zr, Hf, Si, Cd, and U were alloyed with plutonium to determine their effect on stabilization of the beta phase. Zirconium was found to be the ' most effective. Kinetic studies were conducted on Pu-Zr alloys having 0.24, 0.65, and 1.7 at.% Zr contents. The beta to alpha transformation in the Pu-Zr alloys was somewhat similar to that in unalloyed plutonium. The main difference being that time, temperature, transformation curves of the alloys were shifted to the right as the zirconium concentration increased. It was determined that the amount of beta phase retained at room temperature increased as the zirconium concentration increased. The minimum amount of Zr needed to stabilize the beta phase of plutonium at room temperature was determined to be 2.0 at.%. A 2.4 at.% Zr addition stabilized the beta phase of plutonium at atmospheric pressure from room temperature to 265 deg C. During mechanical property testing it was determined that the stabilized beta Pu-2.4 at.% Zr alloy was brittle from room temperature to 230 deg C. Both tensile and compression strengths of the beta stabilized alloy were greater than the unalloyed beta phase of plutonium. A brittle-ductile transition was noted between 130 and 180 deg C on the Pu-0.65 at.% Zr alloy. Age hardening studies were conducted at room temperature with a Pu -2.4 at.% Zr alloy. A slight aging effect was noted due to the precipitation of an intermetallic compound. Compression tests on the Pu-2.4 at.% Zr alloy indicated that below 80 deg C the stabilized beta phase started to transform to alpha phase during the application of compressive loads. (auth)
RECOMBINATION STATISTICS FOR THE NEUTRON-INDUCED BASE CURRENT COMPONENT.
No Description Available.
Theory of ordering transformations in metals and minerals
This dissertation presents an investigation of ordering in FCC based systems using the pair potential approximation in the ground state and mean field limits. The theoretical approach is used to explain the occurrence of observed equilibrium phases and characteristics of thermodynamic instabilities, in particular, spinodal ordering and decomposition. It is shown that the stability of non-integer domain sizes in long period superstructures such as Al{sub 3}Ti and Ag{sub 3}Mg may result from the tendency of a system to reduce the number of non-dominant ordering waves, thus producing domain sizes that have rational fraction form n/m. This conclusion is used to explain the domain size stability with respect to variations in temperature and electron concentration. The cation ordering in the precipitate phases in calcite and dolomite is analyzed by analogy with ordering in FCC based metals. The ordered phases in calcite and dolomite are shown to be consistent with pair potential minima at {l brace}100{r brace} and {l brace}1/2, 1/2, 1/2{r brace} positions in reciprocal space respectively. 32 refs., 6 figs.
INTERACTION OF TWO-DIMENSIONAL, STRATIFIED, TURBULENT AIR--WATER AND STEAM-- WATER FLOWS.
No Description Available.
Transient Temperature Distributions in a Thermally Orthotropic Plate With Non-Uniform Surface Heating
ent temperature variation in a thermally orthotropic plate which is subjected to an arbitrary heating rate distribution along one face with all other surfaces being insulated. Dimensionless temperature histories and distributions determined from this solution are presented for the special, but representative, case of a linearly varying heating rate distribution on plates with varying degrees of thermal orthotropy. These results establish quantitatively the value of a material with high planar and low normal thermal conductivities for applications where it is desired to maintain minimum temperatures on the rear or unheated surface of a heat shield when the heated surface is subjected to a very non-uniform heating rate distribution. The applicability of simplifying assumptions in analyzing such a system is discussed. Experimental temperature measurements in a pyrolytic graphite plate heated by an oxyacetylene flame were made to verify the analytical results. Achievement of satisfactory agreement wss found to be dependent upon use of thermal property values differing from those presently available for this material. This is not unusual in that differences in production methods are known to introduce substantial property variations in anisotropic materials such as pyrolytic graphite. (auth)
LOW TEMPERATURE COOPERATIVE BEHAVIOR OF THE RARE EARTH SALTS GdCl$sub 3$ AND PrCl .
No Description Available.
Spectroscopy of transition metal species in rare gas matrices. I. Vanadium metal. II. Sulfides. III. Carbonyl complexes. IV. Dinitrogen complexes. V. Homonuclear diatomic compounds
No Description Available.
Noise Considerations in Nuclear Pulse Amplifiers
The effects of certain pulse-shaping networks on the signal-to-noise ratio of a nuclear pulse amplifier were considered. The shaping networks discussed are: equal RC-integrating and RC-differentiating time constant, single- delay-line clipper and RC integrator, and doubledelay-line clipper and RC integrator. The effects of these networks on the signal, when high count rates and overload pulses are present, were also considered. Equations and curves were developed for the energy resolution (signal-tonoise ratio) and resolving time (related to the ability to operate at high counting rates) of the networks. Experimental results are shown for the energy resolution of the types of pulse- shaping networks considered. (auth)
A. The Preparation of Dilute, Dry, Nonaqueous Solutions of Molecular Iodine Inoculated With Iodine-131. B. The Distribution of Molecular Iodine Between Cyclohexane and Aqueous Solutions.
No Description Available.
A Theoretical Study of the Transient Operation and Stability of Two-Phase Natural Circulation Loops
Mathematical models of the time-dependent behavior of two-phase natural- circulation loops were used to predict the operation and to explain the unusual instability sometimes observed. The initial results obtained for a loop similar to the Univ. of Minnesota loop were used to formulate a more complex and accurate model, and the predicted transient behavior was in close agreement with the experimental results from the Minnesota loop. For a 300psia, high-pressure loop, unstable oscillatory behavior was predicted under certain conditions and stable behavior under others. Closed unstable regions rather than limits were predicted, and the specifications of stability in terms of a single parameter were found to be impossible. The great difference in oscillatory frequencies observed at low and high pressures was found to be due largely to the system geometry. The criterion for the absence of oscillations was found to be similar to one of the criteria for stability of chemical reaction systems. (D.L.C.)
Fall and winter movements and activity of muskrats in east-central Minnesota
No Description Available.
THICKNESS CORRECTIONS FOR NEUTRON-ACTIVATED GOLD FOILS.
No Description Available.
Formal analysis of name accessing in programming languages. [R]
No Description Available.
Low Temperature Thermoluminescence of Gamma Irradiated Potassium Dihydrogen Phosphate
Thermoluminescence in potassium dihydrogen phosphate (KDP) induced by Co/ sup 60/ gamma irradiation at liquid nitrogen temperature (-198 deg C) was investigated. Glow curves in the temperature range --196 to 0 deg C were measured for a series of gamma exposure dosages ranging from 10/sup 4/ roentgen to 5 x 10/sup 6/ roentgen. The heating rate used for glow curve measurements was 12 deg C per minute. Twice recrystallized Mallinckrodt reagent grade potassium dihydrogen phosphate, with a grain size between 100 and 170 mesh, was used for most samples. In the case of the powder samples, the glow curve for an exposure dose of 10/sup 4/ roentgen exhibited two peaks in this temperature range, one at approximately --78 deg C and the other at approximately -146 deg C. The -78 deg C peak split into two distinct peaks with increasing dosage. At still higher doses an additional peak at about -9 deg C became evident. This peak may, however, be due to aluminum oxide. Calculation of the trap depth, E, and the frequency factor, s, associated with the --78 deg C peak, by the approximate method of Grossweiner yielded values of 0.485 ev and 9.97 x 10/sup 10/ sec/sup -1/ for E and s, respectively. Calculation of the trap depth corresponding to this glow peak was also made using the method described by Bonfiglioli, Brovetto, and Cortese. The value obtained was approximates -0.2 ev. Treatment of the --148 deg C glow peak by the method of Bonfiglioli, Brovetto, and Cortese gave values of approximates 0.1, approximates 0.35, and approximates 0.2 ev for glow curves resulting from exposure doses of 10/sup 4/, 10/sup 5/, and 10/sup 6/ roentgens, respectively. Glow curves were measured for two KDP single crystals, each exposed to 10/sup 4/, 10/sup 5/, and 10/sup 6/ roentgens with subsequent …
Americium and plutonium in water, biota, and sediment from the central Oregon coast
Plutonium-239, 240 and americium-241 were measured in the mussel Mytilus californianus from the region of Coos Bay, OR. The flesh of this species has a plutonium concentration of about 90 fCi/kg, and an Am-241/Pu-239, 240 ratio that is high relative to mixed fallout, ranging between two and three. Transuranic concentrations in sediment, unfiltered water, and filterable particulates were also measured; none of these materials has an Am/Pu ratio as greatly elevated as the mussels, and there is no apparent difference in the Am/Pu ratio of terrestrial runoff and coastal water. Sediment core profiles do not allow accumulation rates or depositional histories to be identified, but it does not appear that material characterized by a high Am/Pu ratio has ever been introduced to this estuary. Other bivalves (Tresus capax and Macoma nasuta) and a polychaete (Abarenicola sp.) do not have an elevated Am/Pu ratio, although the absolute activity of plutonium in the infaunal bivalves is roughly four times that in the mussels.
The Specific Heat of Dysprosium Metal Between 0.4 and 4 K
Submitted to Illinois Inst. of Tech., Chicago. A He/sup 3/ cryostat was built to measure the specific heat of rare earth metals which have a component, at low temperatures, attributable to the electrons in the incomplete 4f shell. The specific heat of dysprosium from 0.4 to 4.2 deg K was measured. Pertinent theories about specific heats are outlined. The apparatus included the cryostat, vacuum and He/sup 3/ systems, calorimeter, carbon thermometer, heater, and magnetic thermometer. The experimental procedure is described and results are presented in graphic and tabular form. The specific heat rose sharply below 1 deg K. An anomalous hump was centered about 2.35 deg K. (M.C.G.)
Response of Shortgrass Plains Vegetation to Chronic and Seasonally Administered Gamma Radiation
In order to determine the effect of radiation on the structure of native shortgrass plains vegetation, an 8750 Ci 137Cs source was installed on the Central Plains Experimental Range near Nunn, Colorado; The experimental area was divided into 6 treatment sectors, a control, 2 sectors for chronic exposure (irradiation initiated April 1969 and continuing as of August 1971), and one each for spring, summer and late fall seasonal semi-acute (30 day), exposures which were administered during April, July and December, 1969, respectively. Community structure was measured by coefficient of community and diversity index. Yield was determined by clipping plots in September 1970 and visual estimates in September 1969 and 1970 for the grass-sedge component of the vegetation. Individual species sensitivity was determined by density data recorded in April, June and September of 1969 and 1970 and by a phenological index recorded at weekly intervals during the 1969 and 1970 growing seasons. The response of the vegetation was similar whether determined by coefficient of community or diversity with diversity being a more sensitive measure of effects. In the chronically exposed sectors, the exposure rate which resulted in a 50 per cent reduction in these 2 parameters (CC50 or D50) was still decreasing the second growing season and was approximately 18 R/hr for the CC50 as of June 1970 and 10 R/hr for the D50 as of September 1970. For the seasonally exposed sectors, the late fall period (December, 1969) was the most sensitive, summer (July, 1969) the least sensitive and spring (April, 1969) intermediate with CC50 and D50 values of 195 and 90, 240 and 222, and 120 and 74 R/hr for the spring, summer and late fall exposed sectors, respectively. Yield and density data indicated a rapid revegetation of the spring and summer exposed sectors during 1970 as a result …
THE EFFECTIVE ALPHA ACTIVITY OF $sup 238$Pu DIOXIDE MICROSPHERES.
No Description Available.
X-Ray Mass Absorption Coefficients and Quantitative Microanalysis of Metallurgical Systems, Including Refractory Metal-Interstitial Compounds.
No Description Available.
Dynamic Simulation of Multi-Pass Pressurized Water Nuclear Power Plants by Analog Computer Techniques
A kinetic model of the primary loop of a multi-pass pressurized water reactor power plant is developed to evaluate, by analog computer techniques, the transient response characteristics under conditions of steam generator load and reactor control rod perturbations. Using the 2-pass 28 Mw(t) SM-2 reactor as a typical plant, transient behavior patterns are illustrated and examined for a variety of load inputs, variations in plant constants, and analog model simplifications. (auth)
Solid State Neutron Detectors
No Description Available.
Parametrization of net radiation at the surface using data from the Wangara experiment
Hourly Wangara boundary layer data (Clark et al., 1971) was used to substantiate previously derived empirical equations of the surface radiation budget. These equations only require measurements taken by a surface observer in order to be evaluated. A parameterization was made for infrared (IR) radiation. From this procedure, a residual radiation was obtained from the measured daytime net radiation data in order to approximate short wave (SW) radiation. Diurnal trends in radiation and other related meteorological parameters were also evaluated. For IR radiation, the Brunt equation was found to adequately represent effective radiation without clouds. IR attenuation (K-values) of 0.89, 0.64, and 0.51 were calculated for low, middle, and high clouds, respectively. A modification of Beer's Law was derived to evaluate the residual radiation under clear skies as suggested by Flowers et al. (1969) for SW radiation. With the surface albedo assumed at 0.15, a mean turbidity coefficient of 0.16 was determined. Also, the square root of the optical air mass was found to best represent the data in this equation. An analysis of SW cloud attenuation coefficients (C-values) from the residual radiation proved inconclusive. Of considerable importance is the finding that cloud attenuation of the residual radiation behaved nonlinearly. Whereas solutions as high as the fourth order fit the data at noon, quadratic solutions fit well near sunset and sunrise. Overall; relative deviations during the day of the combined parameterization were approximately 20% at noon and just less than 30% for periods up to one hour before sunset or sunrise. Predictions within these one-hour periods, however, contained considerable error, partially due, to the scatter and small magnitude of the measurements. Diurnal trends in surface radiation and other meteorological parameters were established.
REACTIONS OF IODINE ACTIVATED BY RADIATIVE NEUTRON CAPTURE AND ISOMERIC TRANSITION WITH GASEOUS AND CONDENSED STATE POLYHALOMETHANES.
No Description Available.
Low temperature heat capacity of lutetium and lutetium hydrogen alloys
The heat capacity of high purity electrotransport refined lutetium was measured between 1 and 20/sup 0/K. Results for theta/sub D/ were in excellent agreement with theta values determined from elastic constant measurements. The heat capacity of a series of lutetium-hydrogen solid solution alloys was determined and results showed an increase in ..gamma.. from 8.2 to about 11.3 mJ/g-atom-K/sup 2/ for hydrogen content increasing from zero to about one atomic percent. Above one percent hydrogen ..gamma.. decreased with increasing hydrogen contents. The C/T data showed an increase with temperature decreasing below about 2.5/sup 0/K for samples with 0.1 to 1.5 atomic percent hydrogen. This accounts for a large amount of scatter in theta/sub D/ versus hydrogen content in this range. The heat capacity of a bulk sample of lutetium dihydride was measured between 1 and 20/sup 0/K and showed a large increase in theta/sub D/ and a large decrease in ..gamma.. compared to pure lutetium.
Polariton effects in naphthalene crystals
The experimental verification of the two-step nature of energy dissipation of photon energy by a crystal is the subject of this dissertation. The ..cap alpha..(O,O) Davydov component of the lowest energy singlet transition in pure strain-free napthalene single crystals is shown to exhibit an increase in absorption with increasing temperature, due to an increase in polariton damping via polariton-phonon scattering processes. (GHT)
Evaluation of a Behavior Skills Package to Teach Caregivers to Manage Disruptive Behavior during Medical and Dental Appointments
Adults with developmental disabilities that live in large residential settings experience complications due to problem behavior when attending routine medical/dental appointments. This may result in sedation for clients for even the most routine medical/dental appointments. The purpose of this project was to develop a comprehensive staff training program that incorporated best practices to teach direct-support professionals behavior management techniques and best practices for transporting clients to and from routine medical/dental appointments. 4 direct-support professionals at a large residential care facility participated in this project. Multiple probes were conducted utilizing standard role-play exercises to evaluate caregiver acquisition of 16 specific skills related to client information, best practices for client transport, and behavior management. The results indicated that behavior skills training (BST) resulted in caregiver acquisition of all 16 skills during role-play exercises.
College Readiness and Dual Credit Participation of Alternative High School Students
The purpose of this study was to explore the extent to which alternative schools add value to the college readiness of their students, as well as to measure the capacity of alternative school students to successfully complete dual credit courses while enrolled at the alternative school. This mixed methods study utilized an exploratory approach with a descriptive research design to explore the extent to which alternative schools produce college-ready students. The Texas Success Initiative Assessment was used to measure participants' academic readiness levels in mathematics, reading, and writing. Additionally, participants had the opportunity to provide their own perspectives on their college readiness levels through a student survey and semi-structured face-to-face interview. The results of this study reveal that the college readiness levels of alternative high school students varied across academic areas. Of the tested participants, 41.1% were college ready in reading, 52.1% in writing, and 16.7% in mathematics. Additionally, the findings reveal that dual credit course participation was not a viable option because of course prerequisites and the amount of time needed to complete dual credit courses. Results of this study expand on the literature to provide a better understanding of the effectiveness of alternative school programs, the college readiness levels of alternative high school students, and the capacity of alternative high school students to successfully complete college coursework while in high school.
Return to Sport: Improving Athletes' Confidence and Mindset Post-ACL Surgery
This study explored the impact of three psychological interventions over seven weeks - goal setting (GS), GS and imagery (IM), and GS and mindful self-compassion (MSC) - on 20 athletes' (Mage = 16.75 years) pain, cognitive appraisal, depression reinjury anxiety, psychological readiness to return to sport, and range of motion (ROM). IM and GS interventions have demonstrated initial effectiveness; however, no study has examined MSC in relation to post-ACL recovery. All athletes experienced significant decrease in pain (F(2) = 97.30, p = .000) from Week 1 to Week 7 and a significant increase in ROM from Week 2 to Week 7 (F(1) = 77.93, p = .000). All athletes experienced significantly higher depression at Week 1 compared to both Week 2 and Week 7 (F(2) = 9.01, p = .001), and significantly higher difficulty coping with their injury at Weeks 1 and 2 compared to Week 7 (F(2) = 6.32, p = .005). There were no statistically significant effects found between the intervention groups at Weeks 1, 2, and 7. However there were moderate effect sizes between interventions which suggest MSC and IM could help athletes cope with their injury during the first few weeks after surgery, and GS may contribute towards less depression at seven weeks post-surgery. Limitations include small sample size, low power, and use of self-report measures. Results have implications for orthopedic surgeons, physical therapists, and health professionals working with athletes recovering from serious sport injury.
It's Going to be Different, but It's Going to be Okay: Caregiver Perspectives on Autism, Culture and Accessing Care
Through ethnography influenced by public health and anthropological theory, I explored the cultural perceptions of autism among eight caregivers whose children received services from a local Dallas-Fort Worth autism treatment organization. Participant observations and semi-structured interviews with caregivers and program employees provided a rich and nuanced view into the state of care currently available in the DFW area while also highlighting areas for improvement. This research will be used to not only identify the barriers faced by North Texas Families while seeking out care,but also the strategies the organization uses when connecting with families from different backgrounds.
Location Estimation and Geo-Correlated Information Trends
A tremendous amount of information is being shared every day on social media sites such as Facebook, Twitter or Google+. However, only a small portion of users provide their location information, which can be helpful in targeted advertising and many other services. Current methods in location estimation using social relationships consider social friendship as a simple binary relationship. However, social closeness between users and structure of friends have strong implications on geographic distances. In the first task, we introduce new measures to evaluate the social closeness between users and structure of friends. Then we propose models that use them for location estimation. Compared with the models which take the friend relation as a binary feature, social closeness can help identify which friend of a user is more important and friend structure can help to determine significance level of locations, thus improving the accuracy of the location estimation models. A confidence iteration method is further introduced to improve estimation accuracy and overcome the problem of scarce location information. We evaluate our methods on two different datasets, Twitter and Gowalla. The results show that our model can improve the estimation accuracy by 5% - 20% compared with state-of-the-art friend-based models. In the second task, we also propose a Local Event Discovery and Summarization (LEDS) framework to detect local events from Twitter. Many existing algorithms for event detection focus on larger-scale events and are not sensitive to smaller-scale local events. Most of the local events detected by these methods are major events like important sports, shows, or big natural disasters. In this work, we propose the LEDS framework to detect both bigger and smaller events. LEDS contains three key steps: 1) Detecting possible event related terms by monitoring abnormal distribution in different locations and times; 2) Clustering tweets based on their key terms, …
Ex-Offender Reentry: An Analysis of Current Policies and Programs
Recidivism rates among ex-offender populations have consistently remained high. With over 600,000 ex-offenders being released from prison each year, reducing the rate of recidivism among the ex-offender class has become a highly debated issue. Ensuring ex-offenders successfully reintegrate into the community post-incarceration may help to reduce recidivism rates. Through a qualitative thematic analysis, this study examined various policies and program that may impact recidivism rates among ex-offenders. The policies and programs reviewed in this study were categorized among six main themes which were identified in prior literature as the most crucial elements needed for successful reintegration. The findings indicate that while many policy changes have been made to positively impact ex-offender reintegration by allowing initial access to services post-release from prison, more should be done to ensure ex-offenders actually receive needed services.
School System Improvement through Building Leadership, Adult Learning, and Capacity: A Consideration of Instructional Rounds as a Systemic Improvement Practice
The problem of the study was determining the supportive conditions related to instructional rounds (rounds) to understand better what conditions may allow for sustained systemic improvement over time. Three Texas school districts were studied to understand the perceptions of district leaders, principals, teacher leaders, and teachers with regard to the sustainability of instructional rounds as a systemic improvement practice, the supportive conditions necessary for sustainability, the salient characteristics that differentiated rounds from other improvement practices, and the potential of rounds to build organizational capacity. Observation of network rounds visits and document analysis was conducted to determine alignment of perception with observation and documents. Findings include perceptions, themes, and critical factors for the sustainability of rounds as an effective systemic improvement practice. Supportive conditions emerged as the most significant perception expressed by the participants. Implications for action for school districts beginning or continuing implementation of instructional rounds are suggested based upon findings from participant perceptions and observation of networks. Suggestions for future research are shared. With supportive conditions in place, instructional rounds has the potential to serve as an effective systemic improvement practice.
Practices that Influence Instructional Coaches' Perceptions of Effectiveness
As instructional coaches are being implemented across the country, their purpose is reviewed, as well as which types of instructional coaching tend to have the most impact on teachers' instructional growth. In this study, I explored instructional coaching and coaches' perceived effectiveness as they work with teachers. A look at the effect of non-evaluative feedback with an instructional coach, and how that helps sustain teachers' pedagogical practice, is taken into consideration as coaches' work towards developing teacher efficacy. I examined instructional coaching through the conceptual framework of professional development and change. This qualitative study included a focus group, personal narratives, and individual interviews to analyze the components of successful instructional coaching models, and how well instructional coaches feel supported as they work with teachers. Findings demonstrated that instructional coaches perceive their work with teachers to be effective and provided information on the practices and conditions that surround their work. The information gained from the study provides a resource for district leaders to evaluate a current coaching model program, or implement a new coaching model program, within their district.
Non-Isothermal Laser Treatment of Fe-Si-B Metallic Glass
Metallic glasses possess attractive properties, such as high strength, good corrosion resistance, and superior soft magnetic performance. They also serve as precursors for synthesizing nanocrystalline materials. In addition, a new class of composites having crystalline phases embedded in amorphous matrix is evolving based on selective crystallization of metallic glasses. Therefore, crystallization of metallic glasses and its effects on properties has been a subject of interest. Previous investigations from our research group related to laser assisted crystallization of Fe-Si-B metallic glass (an excellent soft magnetic material by itself) showed a further improvement in soft magnetic performance. However, a fundamental understanding of crystallization and mechanical performance of laser treated metallic glass was essential from application point of view. In light of this, the current work employed an integrated experimental and computational approach to understand crystallization and its effects on tensile behavior of laser treated Fe-Si-B metallic glass. The time temperature cycles during laser treatments were predicted using a finite element thermal model. Structural changes in laser treated Fe-Si-B metallic glass including crystallization and phase evolution were investigated with the aid of X-ray diffraction, differential scanning calorimetry, resistivity measurements, and transmission electron microscopy. The mechanical behavior was evaluated by uniaxial tensile tests with an InstronTM universal testing machine. Fracture surfaces of the metallic glass were observed using scanning electron microscopy and site specific transmission electron microscopy. Fe-Si-B metallic glass samples treated with lower laser fluence (<0.49 J/mm2) underwent structural relaxation while higher laser flounces led to partial crystallization. The crystallization temperature experienced an upward shift due to rapid heating rates of the order of 104 K/s during laser treatments. The heating cycle was followed by termination of laser upon treatment attainment of peak temperature and rapid cooling of the similar order. Such dynamic effects resulted in premature arrest of the crystallite growth leading …
Corbicula fluminea Invasion as a Secondary Effect of Hydrilla verticillata Management via Triploid Grass Carp (Ctenopharyngodon idella)
A study of Asian clam (Corbicula fluminea Müller) colonization in relation to changes in aquatic vegetation community as a result of management of Hydrilla verticillata (L. f.) Royle with grass carp was conducted at the Lewisville Aquatic Ecosystem Research Facility (LAERF), Lewisville, TX, from April 2015 through October 2016. Percent vegetation cover, C. fluminea abundance and water quality metrics (pH, turbidity, conductivity, DO, calcium, chlorophyll a) from 16 experimental subjects were analyzed. Treatments included four replicated grass carp stocking densities; 1-control with no fish stocked (n = 4), 2-low density of 40-43 fish per vegetated ha (n = 4), 3-medium density of 72-81 fish per vegetated ha (n = 4) and 4-high density of 110-129 fish per vegetated ha (n = 4). Data analysis showed statistical significance in the relation of C. fluminea abundance to percent vegetation cover (multiple linear regression, r2 = 0.820), grass carp stocking densities (two-way analysis of variance, p = <0.001) and chlorophyll a (multiple linear regression, r2 = 0.339). Findings of this research indicate the possibility that management of hydrilla had enabled establishment of secondary invasive species.
Arduino Based Hybrid MPPT Controller for Wind and Solar
Renewable power systems are becoming more affordable and provide better options than fossil-fuel generation, for not only the environment, but a benefit of a reduced cost of operation. Methods to optimize charging batteries from renewable technologies is an important subject for off-grid and micro-grids, and is becoming more relevant for larger installations. Overcharging or undercharging the battery can result in failure and reduction of battery life. The Arduino hybrid MPPT controller takes the advantage of solar and wind energy sources by controlling two systems simultaneously. The ability to manage two systems with one controller is better for an overall production of energy, cost, and manageability, at a minor expense of efficiency. The hybrid MPPT uses two synchronous buck DC-DC converters to control both wind and solar. The hybrid MPPT performed at a maximum of 93.6% efficiency, while the individual controller operated at a maximum 97.1% efficiency when working on the bench test. When designing the controller to manage power production from a larger generator, the inductor size was too large due to the frequency provided by the Arduino. A larger inductor means less allowable current to flow before the inductor becomes over saturated, reducing the efficiency of the controller. Utilizing a different microcontroller like the PIC16C63A produces a much faster frequency, which will reduce the inductor size needed and allow more current before over saturation.
The Effects of Multicultural Discussions and Supervisory Working Alliance on Multicultural Counseling Competence
This study examined the influence of multicultural training, multicultural discussions in supervision, and the supervisory working alliance on multicultural counseling competence. The sample consisted of 57 doctoral counseling interns, doctoral graduate students and post-doctoral students in counseling and clinical psychology. Participants completed several instruments including a demographic questionnaire, the Supervisory Working Alliance Inventory - Trainee, and the Multicultural Counseling Inventory. They filled out two questionnaires created for this study, one assessing multicultural discussions in supervision and another quantifying their multicultural training experience. Data analyses included multiple hierarchical regression, utilizing the Hayes PROCESS macro. Multicultural discussions in supervision moderated the relationship between the supervisory working alliance and multicultural counseling competence, but did not significantly moderate the relationship between multicultural training and multicultural counseling competence. Findings suggest that when multicultural discussions in supervision are positive, they significantly increases the strength of the relationship between good supervisory working alliance and multicultural counseling competence in psychology trainees. The findings may inform supervision practices and improve multicultural counseling competence in psychology graduate student trainees.
How Does It Feel to be Creative? A Phenomenological Investigation of the Creative Experience in Kinetic Places
How does it feel to be creative? Such a question, when approached from a phenomenological perspective, reveals new understandings about the embodied experience of creativity, and how it feels as it is being lived. This investigation begins with a provocative contrast of two environments where creativity is thought to manifest itself: school art classrooms, where creativity is often legislated from an authority figure, and New Orleans Second Line parades, where creativity is organically and kinetically expressed. A thorough review of the literature on creativity focuses on education, arts education, creative economies, psychology, and critical theorists, collectively revealing a cognitive bias and striking lack of consideration for community, freedom, and the lived experience of being creative. Further discussions in the literature also neglect sites of creativity, and the impact that place (such as a school classroom) can have upon creativity. The phenomenological perspectives of Merleau-Ponty, Heidegger, Bachelard, and Trigg support a methodological lens to grasp embodied knowledge, perceptions of placedness on creativity, and the interdependent frictions between freedom, authenticity, movement and belonging. The research method includes investigations in New Orleans in archives, examination of visual and material culture, participation in cultural practice, and formal and informal interviews. Further, the phenomena of walking and wandering became a methodology for embodied data collection that clarified the emerging rich experiences and descriptions of how it feels to be creative, especially how it feels to be creative in a creative place. What is also revealed are intense frictions, such as the tension between perceptions of personal freedom and a high demand for authenticity in terms of New Orleans traditions, that opens the space and fuels the inspiration for the abundance of creativity found in New Orleans culture.
Supportive Systems for Building Capacity of the Elementary Instructional Coach
The purpose of this qualitative case study was to examine the systems in place to build the capacity of elementary instructional coaches in a fast-growth district. Through syntheses of research from educational scholars, the conceptual framework was developed with a focus on building capacity of instructional coaches in an ever-changing environment of fast-growth through the lens of professional learning communities, human and social capital, and support from district and campus administration. This study assessed the perceptions of six instructional coaches, six principals, and six district leaders from Rose ISD regarding the school district's support for building the capacity of instructional coaches within the elementary instructional coaching program. The three-part data collection process included document analysis, in-depth interviews, and focus group interviews to support triangulation of data. Through the a priori coding process, the following four themes emerged that highlight key components needed to support district leaders in establishing systems to build the capacity of instructional coaches in an ever-changing environment caused by fast growth: structured time for professional learning, program clarity, collaborative support systems, and implementation of a professional learning community framework. This study revealed a specific need to further understand systems for monitoring and evaluating the effectiveness of the instructional coaching program in an ever-changing environment of a fast-growth district.
When to Say It: Establishing a Verbal Cue
Dog trainers sometimes teach verbal cues by saying the cue as the dog is performing the desired behavior. However, there is disagreement about when to say the cue. In this study, a pet dog was trained to go to three different apparatus, the cue for each of which was given at a different time, in a multi-element design. The cue "hoop" was given just as the dog began to move to the hoop apparatus. The cue "carrier" was given as the dog was stepping into the carrier apparatus. The cue "platform" was given after the dog was sitting on the platform apparatus. To test if the dog had learned the cues, the trainer had the dog sit and gave the cue. During testing, if only the correct apparatus was present, the dog responded to all three cues. However, when all three apparatus were present, the dog only responded correctly to the "hoop" cue. This suggests that giving the cue just as the learner is beginning to perform the desired behavior is the most effective teaching method.
Musical Priming and Operant Selection
Language is a cultural construct, and the relationship between words is taught. Priming research has long investigated the relationship between related and unrelated words. Similar research has been seen in music relationships, but most of these investigate harmonic relations despite the melodic relationship being the one listeners are mostly likely to describe. Further, these studies typically measure existing relationships and do not attempt to teach a new relationship, nothing that most adults are experienced musical listeners. This study seeks to establish a new melodic relationship (the enigmatic Scale) in addition to a familiar one (the major Scale) while measuring response time to the musical sequences. A baseline was conducted in which participants listened to a musical sequence and selected via response box if the final note is consonant (major Scale) or dissonant (enigmatic Scale). Following baseline a training section occurred in which participants heard sequences ranging from 2-7 notes and were provided feedback for correct and incorrect responses. Following completion of the training participants completed a post-test identical to baseline. Behavioral results are discussed in relation to Palmer's (2009) concept of the repertoire.
Shear and Bending Strength of Cold-Formed Steel Solid Wall Panels Using Corrugated Steel Sheets for Mobile Shelters
The objective of this thesis is to determine if the single sided resistance spot weld (RSW) can be used as a feasible connection method for cold formed steel (CFS) shear walls subject to lateral force of either seismic or wind loads on mobile shelters. The research consisted of three phases which include: a design as a 3D BIM model, connection tests of the resistance spot weld, and full-scale testing of the designed solid wall panels. The shear wall testing was conducted on specimens with both resistance spot weld and self-drilling screws and the results from tests gave a direct comparison of these connections when the solid wall panel was subjected to in-plane shear forces. The full-scale tests also included 4-point bending tests which was designed to investigate the wall panel's resistance to the lateral loads applied perpendicularly to the surface. The research discovered that the singled sided resistance spot weld achieved similar performance as the self-drilling screws in the applications of CFS wall panels for mobile shelters. The proposed single sided resistance spot weld has advantages of low cost, no added weight, fast fabrication, and it is a feasible connection method for CFS wall panels.
Modeling of High Strain Rate Compression of Austenitic Shape Memory Alloys
Shape memory alloys (SMAs) exhibit the ability to absorb large dynamic loads and, therefore, are excellent candidates for structural components where impact loading is expected. Compared to the large amount of research on the shape memory effect and/or pseudoelasticity of polycrystalline SMAs under quasi-static loading conditions, studies on dynamic loading are limited. Experimental research shows an apparent difference between the quasi-static and high strain rate deformation of SMAs. Research reveals that the martensitic phase transformation is strain rate sensitive. The mechanism for the martensitic phase transformation in SMAs during high strain rate deformation is still unclear. Many of the existing high strain rate models assume that the latent heat generated during deformation contributes to the change in the stress-strain behavior during dynamic loading, which is insufficient to explain the large stress observed during phase transformation under high strain rate deformation. Meanwhile, the relationship between the phase front velocity and strain rate has been studied. In this dissertation, a new resistance to phase transformation during high strain rate deformation is discussed and the relationship between the driving force for phase transformation and phase front velocity is established. With consideration of the newly defined resistance to phase transformation, a new model for phase transformation of SMAs during high strain rate deformation is presented and validated based on experimental results from an austenitic NiTi SMA. Stress, strain, and martensitic volume fraction distribution during high strain rate deformation are simulated using finite element analysis software ABAQUS/standard. For the first time, this dissertation presents a theoretical study of the microscopic band structure during high strain rate compressive deformation. The microscopic transformation band is generated by the phase front and leads to minor fluctuations in sample deformation. The strain rate effect on phase transformation is studied using the model. Both the starting stress for transformation and …
Understanding the Perceptions and Indications of the Goals and Unique Aspects of the Foundations for Success (FFS) Curriculum Model: A Case Study in a North Texas Private Preschool
This quantitative and qualitative case study examined the educators' perceptions of both the goals and unique aspects of the foundations for success (FFS) curriculum model. Specifically, this study was designed to explain the experiences of 55 early childhood educators and administrators who all had similar exposure to the FFS curriculum model. This study sought to understand the educators' perceptions of the specific goals of using pertinent curriculum and instruction terminology and the parallel process of content language, connecting the importance of developmentally appropriate practices (DAP) and learning standards and readiness for kindergarten. In the same way, the perceptions of the unique aspects of the value based curriculum, the use of reflective supervision and the use of design thinking were gathered and interpreted. This study looked closely into program successes, challenges and future implications of the FFS curriculum model. This study also considered the extent to which future implementations of the model could change the current interdependent relationship between early childhood education and the primary grades. The researcher analyzed the perceptions, utilizing the Likert-value survey instrument responses, the open-ended survey responses, along with the focus group responses to triangulate the findings. Common themes shared across all data collection were evaluated and described. The most apparent themes derived from the findings included the following: the importance of relationships; the importance of accountability and the role language plays; the necessity of the consideration of children's interest for optimal development; and the recognition of intentional planning, revisiting and reflection to the process of the FFS curriculum model. Overall, the FFS curriculum model was determined to be a curriculum model that takes educators on a continuous journey of thinking and learning. Evidence was gathered for the FFS curriculum model that implicated the possibility for replication of the model in other schools, as well as further …
ANALYTICAL AND EXPERIMENTAL STUDIES OF DOUBLE-PIPE COUNTER-FLOW LIQUID METAL HEAT EXCHANGERS.
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Ejection of Large Fragments in High-Energy Nuclear Reactions
Several features of the production of Na/sup 24/ and Mg/sup 28/ fragments produced in the interaction of protons and He ions with Cu, Ag, Au, and U were investigated. Formation cross sections were determined for He ions of different energies between 320 and 880 Mev and for protons of 700 Mev. Thick- target recoil experiments were performed at bombarding energies of 0.7 and 3 Bev for protons, and 880 Mev for He ions. Also given are some recoil measurements of Na/sup 24/ from Al. Analysis of data obtained with target materials heavier than Al showed that for the bombarding energies used, Na/sup 24/ and Mg/sup 28/ are probably produced by the cleavage of the target nucleus into two heavy fragmerts. One of these fragments has a mass approximately equal to the mass Na 4 or Mg/6 and the other contains most of the remaining mass of the target nucleus. However, Na/sup 24/ and Mg/sup 28/ are very probably not slowly evaporated particles nor products of a slow fission process. The experimental information covering fragmentation from photographic emulsion studies and radiochemical studies is discussed. The various mechanisms proposed are considered and a new one suggested. According to this new mechanism Na/sup 24/ Mg/sup 28/ and the more energetic fragments observed in nuclear emulsions are ejected promptiy from the parent nucleus by very complex nucleon-nucleon cascades and by collective effects. (auth)
Effect of Alloying Additions on Corrosion Behavior of Nickel--Molybdenum Alloys in Fused Fluoride Mixtures.
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Slogan Word Count and the Effects on Consumer Behavior
Slogans can be attributed as a way in which to communicate a brand's message to its key consumer. An effectively established brand amongst targeted consumers can in turn generate profitability and ever further promote the brand. The purpose of this paper was to investigate the effectiveness of advertisements that employ vague or precise cosmetic product brand slogans among both male and female consumers. Ultimately, the end goal of marketing is to make a sale. Additionally, the purpose of this study was to determine whether or not the length of a slogan is an influential factor on the participant's motivation to purchase a cosmetic or skincare product. Data was collected through the use of survey in an online social media format, in order to test the effectiveness of different lengths of slogans for slogan recall, brand recall, brand awareness and purchase intention. Prior research and hypotheses were used to predict the concept that shorter more concise or precise slogans in this study would heighten the levels of all measured variables in the study, slogan recall, brand recall, brand awareness and purchase intention. The results of this paper conclude overall vague slogans have the potential to reach higher levels of slogan recall ability , brand recall and the intent to purchase, on the contrary shorter more precise slogans affect brand awareness at a greater level than the lengthier slogans.
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