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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Reliability and Validity of the Chinese Version Assessment of Promoting the Emergence of Advance Knowledge (PEAK), Direct Training Module

Cheng, Hua 01 December 2017 (has links)
The Mandarin Chinese version of the first PEAK module (Direct Training) assessment was created and compared to the English version, by examining alternate-form reliability and cross-cultural validity. Thirty-two typically developing children under 10 years old (19 males and 13 females) residing in USA, Canada, and mainland China were recruited and assessed by bilingual parents with both language versions of PEAK-DT assessments. Statistical results show that the two language versions had strong correlations between the PEAK raw scores (r = .98), the component raw scores (r ranged .93 to .98), and the component age-referenced scores (r ranged .77 to .93). Equivalence between the two versions was also demonstrated by high test-retest percentage of agreement on all items as well as scored items, (88%, and 92% respectively). No significant testing effects were observed across the test-retest intervals, and no differences were observed in terms of the assessors’ English proficiency. Furthermore, 183 out of the 184 items in the PEAK-DT assessments rejected the null hypothesis of One-Sample Chi-square test (p < .05 at confidence level of 95%), indicating that the globally high percentage of agreement from both versions was the result of valid translation. In summary, the Chinese version of the PEAK-DT assessment exhibited cross-cultural reliability and validity, which may lay the foundation for the future research on the use of the PEAK system with the Chinese community.
12

APPLICABILITY OF MASS SPECTROMETRY TO DETECT COELUTING IMPURITIES IN HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

ANTONOVICH, ROBERT STEVEN 16 September 2002 (has links)
No description available.
13

Geology of the Granite Peak stock area, Whetstone Mountains, Cochise County, Arizona

DeRuyter, Vernon Donald January 1979 (has links)
No description available.
14

Landform studies in the Peak District of Derbyshire

Pitty, Alistair F. January 1966 (has links)
No description available.
15

Peak Travel in a Megacity: Exploring the Role of Infrastructure Saturation on the Suppression of Automobile Use

January 2014 (has links)
abstract: Contrary to many previous travel demand forecasts there is increasing evidence that vehicle travel in developed countries may be peaking. The underlying causes of this peaking are still under much debate and there has been a mobilization of research, largely focused at the national scale, to study the explanatory drivers but research focused at the metropolitan scale, where transportation policy and planning are frequently decided, is relatively thin. Additionally, a majority of this research has focused on changes within the activity system without considering the impact transportation infrastructure has on overall travel demand. Using Los Angeles County California, we investigate Peak Car and whether the saturation of automobile infrastructure, in addition to societal and economic factors, may be a suppressing factor. After peaking in 2002, vehicle travel in Los Angeles County in 2010 was estimated at 78 billion and was 20.3 billion shy of projections made in 2002. The extent to which infrastructure saturation may contribute to Peak Car is evaluated by analyzing social and economic factors that may have impacted personal automobile usage over the last decade. This includes changing fuel prices, fuel economy, population growth, increased utilization of alternate transportation modes, changes in driver demographics , travel time and income levels. Summation of all assessed factors reveals there is at least some portion of the 20 billion VMT that is unexplained in all but the worst case scenario. We hypothesize that the unexplained remaining VMT may be explained by infrastructure supply constraints that result in suppression of travel. This finding has impacts on how we see the role of hard infrastructure systems in urban growth and we explore these impacts in the research. / Dissertation/Thesis / M.S. Civil Engineering 2014
16

The effect of sprint interval training on non-invasively determined peak cardiac output and the role of biological sex

Bostad, William January 2023 (has links)
Sprint interval training (SIT) increases peak oxygen uptake (VO2peak) but the mechanistic basis is unclear. The Fick principle broadly attributes increases in VO2peak to changes in peak cardiac output (Qpeak) and/or peak arteriovenous oxygen difference (peak a-vO2diff). The main purpose of this thesis was to investigate the role of Qpeak, measured non-invasively using inert gas rebreathing (IGR), on SIT-induced changes in VO2peak. It also considered the time course of these responses and the influence of biological sex. The SIT protocol involved 3 x 20-s “all out” sprints performed within a 10-min session of low-intensity cycling. Study 1 measured Qpeak after 2, 6, and 12 weeks of SIT and found it was increased after 12 weeks and associated with the change in VO2peak. Peak a-vO2diff, estimated based on the Fick equation (peak a-vO2diff = VO2peak/Qpeak), was also increased after SIT and associated with the change in VO2peak. Study 2 found that a novel constant-load protocol elicited Qpeak values that were non-inferior to an established step protocol, within a margin of 0.5 L/min. Both protocols elicited VO2 values at Qpeak that were similar to VO2peak. The constant load protocol had similar day-to-day repeatability as the VO2peak test (typical error = 6.6 and 6.4%, respectively). Study 3 investigated an exploratory finding from Study 1 that suggested Qpeak was increased in male but not female participants. The design was similar, but Study 3 employed suggested best practices for making sex-based comparisons. Contrary to our hypothesis, Qpeak was unchanged after 12 weeks of SIT and there was no sex-based difference. Like Study 1, peak a-vO2diff was increased and correlated with VO2peak. This thesis advances knowledge regarding the influence of SIT on Qpeak determined non-invasively and highlights the need for more mechanistic work to comprehensively assess the basis for the increase in VO2peak. / Thesis / Candidate in Philosophy / Sprint interval training (SIT) is a form of exercise that involves brief bursts of near-maximal to “all out” efforts separated by short recovery periods. The method improves cardiorespiratory fitness — an important health marker that is quantified as the highest amount of oxygen used by the body during strenuous exercise (VO2peak) — but the mechanisms are not well understood. This thesis examined the effect of SIT on peak cardiac output (Qpeak), which is the highest rate of blood pumped by the heart each minute, and the relationship to changes in VO2peak. Qpeak was measured non-invasively by having participants breathe an inert gas mixture. Two separate 12-week training studies confirmed that SIT increased VO2peak but yielded conflicting results regarding the role of Qpeak. The findings also suggest that the capacity of skeletal muscles to extract oxygen is increased after SIT. Biological sex does not appear to influence SIT-induced changes in Qpeak or VO2peak.
17

Geology of the Squaw Peak porphyry copper-molybdenum deposit, Yavapai County, Arizona

Roe, Robert Ralph, 1950- January 1976 (has links)
No description available.
18

AN INVESTIGATION OF THE VALIDITY OF PEAK-T: AN ASSESSMENT OF RELATIONAL RESPONDING, NORMATIVE SAMPLING, AND IQ

Walker, Brooke 01 December 2018 (has links)
Assessing higher-level verbal repertoires of individuals with autism and related intellectual disabilities is crucial due to the language and cognitive deficits experienced by this population as well as is the need for valid assessment tools for data-driven and individualized treatment. In addition to, curricula or instructional protocols that produce changes toward improvement of language and cognitive skills are vital to the overall well being of these individuals. Several assessments and instructional guides are available to behavior analysts however few have demonstrated evidence of validity, reliability, and/or utility in its effectiveness in producing causal changes in higher-level cognition and adaptive ability. The presentation will present correlational data between PEAK-T with IQ (WISC-V) as well as provide preliminary normative sample data of PEAK-T-PA with neuro-typical children.
19

Geochronologic Constraints On The Timing Of Metamorphism And Exhumation Of The Tillotson Peak Complex In Northern Vermont

Aiken, Cheyne 01 January 2018 (has links)
The Tillotson Peak Complex (TPC) in northern Vermont records high-pressure (HP) subduction zone metamorphism that occurred during the Ordovician Taconic Orogeny, and subsequent retrograde metamorphism and deformation that occurred during the Silurian Salinic Orogeny. Previous studies have documented a polymetamorphic history, with peak metamorphic pressures possibly up to 2.5 GPa and temperatures of 550°C. Prior to this research, constraints on the timing of metamorphism in the TPC were limited to a single Middle Ordovician 40Ar/39Ar total fusion age for glaucophane. This study integrates 40Ar/39Ar step heating analyses of multiple mineral phases and U-Pb dating of titanite with field and microstructural observations to further constrain the subduction–exhumation history of the TPC. Microstructural and petrologic analyses in thin section on samples of felsic gneiss, pelitic schist, amphibolite, and blueschist suggest deformation during varied P-T conditions. The earliest and highest-pressure metamorphic event documented in the TPC samples is associated with inclusions in garnet and white mica in S1 quartz microlithons. Inclusions of paragonite, titanite, and omphacite in garnets, locally defining S1, suggest that some blueschist may have formed in the retrograde path in association with the S2 foliation. A greenschist-facies metamorphic overprint in most samples is also associated with S2, primarily defined by epidote, white mica, and chlorite. E-W trending F2 intrafolial folds are commonly rootless in outcrop, locally defined by blueschist–eclogite-facies fold noses. Kinematic indicators relative to S2 and L2 stretching lineations give a predominantly top-to-the-E shear sense. S3 crenulation cleavage development is related to folding about E-W trending F3 folds that define the map pattern of the Tillotson Peak Complex. Locally developed S4 crenulations are axial planar to the NW-trending Gilmore Antiform. Additionally, D4 deformation and metamorphism is recorded by microfractures in garnet and epidote, as well as chlorite pseudomorphs after garnet. 40Ar/39Ar step heating of multiple phases and U-Pb dating of titanite yielded ages corresponding with the Taconian to the Salinic orogenies. Ages of ~485–480 Ma are attributed to prograde–peak metamorphism (M1) and S1 development. Ages that span ~471–456 Ma are interpreted to document retrograde M2 metamorphism through greenschist to locally blueschist-facies metamorphic conditions during exhumation and S2 development. Correlation of D3 microstructures in these samples with map-scale folds suggest that E–W trending folds developed in the range of ~455–445 Ma, recorded by minimum apparent ages in the field area, and locally as plateau ages along the margin of the TPC. Younger ages ~435–405 Ma are observed locally in apparent age gradients, and are interpreted to reflect metamorphic overprinting that resulted in the chlorite pseudomorphs after garnet and the growth of actinolite, which may be related to the timing of folding about the Gilmore Antiform. Results presented here suggest the impact of Acadian retrograde metamorphism and deformation on rocks of the TPC may be less significant than previous work suggests.
20

Precoding in MIMO, OFDM to reduce PAPR (Peak to Average Power Ratio)

Ishaq, Muhammad Irfan, Khan, Yasir Ali, Gul, Muhammad Talha January 2012 (has links)
One of the critical issues of systems utilizing Orthogonal Frequency Division Multiplexing (OFDM) is the high peak to the average power ratio of OFDM signals. We have used Precoding as a way to mitigate the PAPR problem. Furthermore the performance of Precoded OFDM in fading multi-path channels has been studied. This thesis is based on an efficient technique for reducing the PAPR of OFDM signals. The proposed technique is data-independent and thus, does not require new processing and optimization for each transmitted OFDM block. The reduction in PAPR of the OFDM signal is obtained through a proper selection of a Precoding scheme that distributes the power of each modulated symbol over the OFDM block. The obtained results show that this Precoding scheme is an attractive solution to the PAPR problem of OFDM signals.

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