title: Analytical description of nonlinear acoustic waves in the solar chromosphere

authors: Litvinenko, Yuri E.

subjects: mathematics

abstract: Vertical propagation of acoustic waves of finite amplitude in an isothermal, gravitationally stratified atmosphere is considered. Methods. Methods of nonlinear acoustics are used to derive a dispersive solution, which is valid in a long-wavelength limit, and a non-dispersive solution, which is valid in a short-wavelength limit. The influence of the gravitational field on wave-front breaking and shock formation is described. The generation of a second harmonic at twice the driving wave frequency, previously detected in numerical simulations, is demonstrated analytically. Results. Application of the results to three-minute chromospheric oscillations, driven by velocity perturbations at the base of the solar atmosphere, is discussed. Numerical estimates suggest that the second harmonic signal should be detectable in an upper chromosphere by an instrument such as the Fast Imaging Solar Spectrograph installed at the 1.6-m New Solar Telescope of the Big Bear Observatory.

text: Analytical description of nonlinear acoustic waves in the solar chromosphere Vertical propagation of acoustic waves of finite amplitude in an isothermal, gravitationally stratified atmosphere is considered. Methods. Methods of nonlinear acoustics are used to derive a dispersive solution, which is valid in a long-wavelength limit, and a non-dispersive solution, which is valid in a short-wavelength limit. The influence of the gravitational field on wave-front breaking and shock formation is described. The generation of a second harmonic at twice the driving wave frequency, previously detected in numerical simulations, is demonstrated analytically. Results. Application of the results to three-minute chromospheric oscillations, driven by velocity perturbations at the base of the solar atmosphere, is discussed. Numerical estimates suggest that the second harmonic signal should be detectable in an upper chromosphere by an instrument such as the Fast Imaging Solar Spectrograph installed at the 1.6-m New Solar Telescope of the Big Bear Observatory.

year: 2017

title: Interview with Michael Apple: The biography of a public intellectual

authors: Peters, Michael A.

abstract: Michael W. Apple is the John Bascom Professor of Curriculum and Instruction and Educational Policy Studies in the Departments of Curriculum and Instruction (CI) and Educational Policy Studies (EPS) at the University of Wisconsin-Madison School of Education where he has taught since 1970. Michael Apple is one of the foremost educational theorists in the world and a public intellectual who is deeply committed to empowerment and transformation of people through education. Professor Apple specializes in understanding and analyzing the relations between education and power. He has made major contributions to the fields of cultural politics, curriculum theory and research, and critical teaching. He has been a tireless advocate and activist-theorist for development of democratic schools over four decades. He began teaching in elementary and secondary schools in New Jersey where he grew up and served as president of the local teachers' union. He has spent his career working with educators, unions, dissident and disadvantaged groups throughout the world on democratizing educational policy and practice. Professor Apple's research centers on the limits and possibilities of critical educational policy and practice in a time of conservative restoration.

text: Interview with Michael Apple: The biography of a public intellectual Michael W. Apple is the John Bascom Professor of Curriculum and Instruction and Educational Policy Studies in the Departments of Curriculum and Instruction (CI) and Educational Policy Studies (EPS) at the University of Wisconsin-Madison School of Education where he has taught since 1970. Michael Apple is one of the foremost educational theorists in the world and a public intellectual who is deeply committed to empowerment and transformation of people through education. Professor Apple specializes in understanding and analyzing the relations between education and power. He has made major contributions to the fields of cultural politics, curriculum theory and research, and critical teaching. He has been a tireless advocate and activist-theorist for development of democratic schools over four decades. He began teaching in elementary and secondary schools in New Jersey where he grew up and served as president of the local teachers' union. He has spent his career working with educators, unions, dissident and disadvantaged groups throughout the world on democratizing educational policy and practice. Professor Apple's research centers on the limits and possibilities of critical educational policy and practice in a time of conservative restoration.

year: 2015

title: Eke Panuku, Eke Tangaroa: He Taonga Tuku Iho

authors: Apanui, Ngahiwi

subjects: Panuku

abstract: He aha te Māori? He aha i kīia ai tētahi āhuatanga, tētahi mahi, tētahi tangata, tētahi whakahaere rānei he Māori? Ko te whāinga o te rangahau nei he rapa huarahi e āhei ai te whakautu i ēnei pātai. Me te huhua hoki o te whakaaro mō ēnei pātai, i huri ahau ki ngā mātanga, ngā pūkenga hoki o te ao mātauranga Māori hei taunaki i te whakautu ki te pātai. 
Ka tūhura te rangahau nei i te rētōtanga o te ao Māori, ka titiro hoki ki te āhua i Māori ai ētahi āhuatanga me te whakautu, he ahurea Māori i Māori ai tētahi āhuatanga, tētahi mahi, tētahi tangata, tētahi whakahaere rānei – ko te pū ahurea Māori tēnei. Ka titiro anō hoki te rangahau nei ki te whakaaro Māori hei tūāpapa mō te pū ahurea Māori, te wāhanga ki ngā kaupapa tuku iho me te whakaatu a te tikanga i te kaupapa. 
Ko te hua o te rangahau nei, he tuku i te rauemi e taea ai te tangata te tautuhi me te ine i te pū ahurea Māori hei ārahi i te aromātaitanga o ngā mahi Māori.

text: Eke Panuku, Eke Tangaroa: He Taonga Tuku Iho He aha te Māori? He aha i kīia ai tētahi āhuatanga, tētahi mahi, tētahi tangata, tētahi whakahaere rānei he Māori? Ko te whāinga o te rangahau nei he rapa huarahi e āhei ai te whakautu i ēnei pātai. Me te huhua hoki o te whakaaro mō ēnei pātai, i huri ahau ki ngā mātanga, ngā pūkenga hoki o te ao mātauranga Māori hei taunaki i te whakautu ki te pātai. 
Ka tūhura te rangahau nei i te rētōtanga o te ao Māori, ka titiro hoki ki te āhua i Māori ai ētahi āhuatanga me te whakautu, he ahurea Māori i Māori ai tētahi āhuatanga, tētahi mahi, tētahi tangata, tētahi whakahaere rānei – ko te pū ahurea Māori tēnei. Ka titiro anō hoki te rangahau nei ki te whakaaro Māori hei tūāpapa mō te pū ahurea Māori, te wāhanga ki ngā kaupapa tuku iho me te whakaatu a te tikanga i te kaupapa. 
Ko te hua o te rangahau nei, he tuku i te rauemi e taea ai te tangata te tautuhi me te ine i te pū ahurea Māori hei ārahi i te aromātaitanga o ngā mahi Māori.

year: 2015