4 resultados para electric variables measurement

em Digital Commons at Florida International University


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The two-photon exchange phenomenon is believed to be responsible for the discrepancy observed between the ratio of proton electric and magnetic form factors, measured by the Rosenbluth and polarization transfer methods. This disagreement is about a factor of three at Q 2 of 5.6 GeV2. The precise knowledge of the proton form factors is of critical importance in understanding the structure of this nucleon. The theoretical models that estimate the size of the two-photon exchange (TPE) radiative correction are poorly constrained. This factor was found to be directly measurable by taking the ratio of the electron-proton and positron-proton elastic scattering cross sections, as the TPE effect changes sign with respect to the charge of the incident particle. A test run of a modified beamline has been conducted with the CEBAF Large Acceptance Spectrometer (CLAS) at Thomas Jefferson National Accelerator Facility. This test run demonstrated the feasibility of producing a mixed electron/positron beam of good quality. Extensive simulations performed prior to the run were used to reduce the background rate that limits the production luminosity. A 3.3 GeV primary electron beam was used that resulted in an average secondary lepton beam of 1 GeV. As a result, the elastic scattering data of both lepton types were obtained at scattering angles up to 40 degrees for Q2 up to 1.5 GeV2. The cross section ratio displayed an &epsis; dependence that was Q2 dependent at smaller Q2 limits. The magnitude of the average ratio as a function of &epsis; was consistent with the previous measurements, and the elastic (Blunden) model to within the experimental uncertainties. Ultimately, higher luminosity is needed to extend the data range to lower &epsis; where the TPE effect is predicted to be largest.

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Post-Soviet Ukraine is in a time of upheaval and transition. Internal relations between pro-Western and pro-Russian supporters have deteriorated in the light of recent political events of Euro Revolution, Russia's occupation of the Crimean peninsula, and the militant confrontations in the southeastern regions of the country. In the light of these developments, intercultural competence is greatly needed to alleviate domestic tensions and enable effective intercultural communication with the representatives of different cultures within the country and beyond its borders.^ This study established a baseline of psychometric estimates of intercultural competence of Ukrainian higher education faculty. A sample of 276 professors of different academic majors from one university in Western Ukraine participated in the research. The Global Perspective Inventory (GPI; Merrill, Braskamp, & Braskamp, 2012) was chosen as a research instrument to measure intercultural competence of the faculty members. The GPI takes into account cognitive, intrapersonal, and interpersonal domains, each of which contains two scales reflective of theories of cultural development and intercultural communication – Cognitive-Knowing, Cognitive-Knowledge, Intrapersonal-Identity, Intrapersonal-Affect, Interpersonal-Social Responsibility, and Interpersonal-Social Interaction. Because the research instrument has neither been previously used as a measure of intercultural competence, nor administered in Ukraine, it was cross-validated using a Table of Specification (Newman, Lim, & Pineda, 2013) and two sets of factor analyses. As a result, a modified version of the GPI was created for use in Ukraine.^ Multiple linear regression analyses were used to test relationships between the participants' GPI scores on intercultural competence, and several independent variables that consisted of academic discipline, intercultural experience, and how long the participants taught at the university. The analyses determined a positive relationship between the scores on three out of six scales of the original version and two out of five scales of the modified version of the GPI and all the independent variables simultaneously. The relationship between the faculty responses on the six scales of both GPI versions and the independent variables controlling for each other produced mixed results. A unique role of intercultural professional development in predicting intercultural competence was discussed.^

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Post-Soviet Ukraine is in a time of upheaval and transition. Internal relations between pro-Western and pro-Russian supporters have deteriorated in the light of recent political events of Euro Revolution, Russia’s occupation of the Crimean peninsula, and the militant confrontations in the southeastern regions of the country. In the light of these developments, intercultural competence is greatly needed to alleviate domestic tensions and enable effective intercultural communication with the representatives of different cultures within the country and beyond its borders. This study established a baseline of psychometric estimates of intercultural competence of Ukrainian higher education faculty. A sample of 276 professors of different academic majors from one university in Western Ukraine participated in the research. The Global Perspective Inventory (GPI; Merrill, Braskamp, & Braskamp, 2012) was chosen as a research instrument to measure intercultural competence of the faculty members. The GPI takes into account cognitive, intrapersonal, and interpersonal domains, each of which contains two scales reflective of theories of cultural development and intercultural communication – Cognitive-Knowing, Cognitive-Knowledge, Intrapersonal-Identity, Intrapersonal-Affect, Interpersonal-Social Responsibility, and Interpersonal-Social Interaction. Because the research instrument has neither been previously used as a measure of intercultural competence, nor administered in Ukraine, it was cross-validated using a Table of Specification (Newman, Lim, & Pineda, 2013) and two sets of factor analyses. As a result, a modified version of the GPI was created for use in Ukraine. Multiple linear regression analyses were used to test relationships between the participants’ GPI scores on intercultural competence, and several independent variables that consisted of academic discipline, intercultural experience, and how long the participants taught at the university. The analyses determined a positive relationship between the scores on three out of six scales of the original version and two out of five scales of the modified version of the GPI and all the independent variables simultaneously. The relationship between the faculty responses on the six scales of both GPI versions and the independent variables controlling for each other produced mixed results. A unique role of intercultural professional development in predicting intercultural competence was discussed.

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My study investigated internal consistency estimates of psychometric surveys as an operationalization of the state of measurement precision of constructs in industrial and organizational (I/O) psychology. Analyses were conducted of samples used in research articles published in the Journal of Applied Psychology between 1975 and 2010 in five year intervals (K = 934) from 480 articles yielding 1427 coefficients. Articles and their respective samples were coded for test-taker characteristics (e.g., age, gender, and ethnicity), research settings (e.g., lab and field studies), and actual tests (e.g., number of items and scale anchor points). A reliability and inter-item correlations depository was developed for I/O variables and construct groups. Personality measures had significantly lower inter-item correlations than other construct groups. Also, internal consistency estimates and reporting practices were evaluated over time, demonstrating an improvement in measurement precision and missing data.