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Purpose The purpose of this study is to examine the effect of students’ self-regulation, co-regulation and behavioral engagement on their performance in flipped learning environments in higher education. Design/methodology/approach The subjects were college students taking an education course offered at a 4-year university in South Korea. Structural equation modeling was adopted to analyze 221 student responses. Findings The findings indicated that the more students self-regulated, the more likely they were to engage in co-regulation with other students in the class. Students’ self-regulation and co-regulation also significantly affected their behavioral engagement. Finally, students’ self-regulation positively affected their academic performance, while co-regulation and behavioral engagement did not affect their performance. Originality/value Based on these findings, this study provides meaningful implications for scholars and practitioners on how to select and use more appropriate instructional and evaluation strategies to improve students’ positive behavior, engagement and performance in a flipped learning environment.

김수환 추기경 선종 이후 그를 기억하기 위한 작업과 연구는 교회 안팎에서 다양하게 이루어져왔다. 추기경에 대한 다각적 연구 사례는 그의 영성과 나눔 정신이 교회 내뿐만 아니라 한국 사회로 확산될 수 있다는 가능성을 열어주었다. 그럼에도 불구하고 종교지도자이자 사회의 지도자로서 그가 지닌 권위의 힘, 즉 카리스마에 대한 연구는 없었다. 더구나 항상 미소를 짓고 있는 추기경의 모습은 늘 당연하다고 여겼을 뿐 연구할 주제라고 생각하지는 않았다. 따라서 본 연구에서는 지금까지 간과되어 왔던 김수환 추기경의 카리스마와 당연하다고 여겨왔던 그의 웃음에 주목하였다. 이를 위하여 먼저 막스 베버의 권위와 카리스마 개념을 살펴보았다. 베버는 신학적 개념인 카리스마를 한 개인이 지닌 ‘권위’의 한 양태를 일컫는 개념으로 새롭게 해석했다. 또한 권위의 한 유형인 카리스마적 권위를 전통적 권위와 합리적-법적 권위와 비교하였다. 베버의 카리스마 개념에서 볼 때, 추기경은 제도권 안에 있는 종교 지도자로서 전통적, 합리적-법적 종교적 권위보다 카리스마적인 종교적 권위가 더욱 크게 드러난 지도자라고 할 수 있다. 그의 삶과 어록을 통해 이러한 카리스마적 종교적 권위를 구체적으로 살펴보았다. 나아가 베버가 말한 카리스마의 일상화 개념을 토대로 은퇴 뒤 퇴색된 추기경의 카리스마적 종교적 권위를 웃음이라는 주제로 새롭게 해석하였다. 추기경의 이미지라 할 수 있는 ‘인자한 미소’를 웃음의 유형에서 학문적 의미를 찾고, 그 웃음을 영성적 관점에서 고찰했다. 마지막으로 막스 베버의 카리스마에 대한 비판적 고찰을 통해 개인에게 집중된 카리스마적 권위를 아이젠슈타트와 쉴스의 이론을 토대로 카리스마의 확산 개념을 살펴보았다. 이로써 추기경의 카리스마가 현재적으로 구현될 인간상을 ‘가톨릭 시민’이라 명명하고, 나아가 가톨릭 시민교육의 필요성을 제안했다.

The synthesis and biological evaluation as potential urotensin-II receptor antagonists of a series of 5-arylfuran-2-carboxamide derivatives 1, bearing a 4-(3-chloro-4-(piperidin-4-yloxy)benzyl)piperazin-1-yl group, are described. The results of a systematic SAR investigation of furan-2-carboxamides with C-5 aryl groups possessing a variety of aryl ring substituents led to identification of the 3,4-difluorophenyl analog 1y as a highly potent UT antagonist with an IC50 value of 6 nM. In addition, this substance was found to display high metabolic stability, and low hERG inhibition and cytotoxicity, and to have an acceptable PK profile.

Recently, magnetic multilayer systems have received again a great attention owing to their suitability for the generation of magnetic chiral spin structure. In this study, we experimentally investigated the interfacial Dzyaloshisnkii-Moriaya interaction (DMI) and the spin-Hall angle (SHA) of magnetic Co/Gd/Pt multilayers with respect to the repetition number $N$ of the multilayers. The DMI and SHA are important variables that govern the stability and mobility of a homochiral spin structure, respectively. The experimental results show that the ratio between the DMI and the dipole energy from the domain wall gradually decreases as $N$ increases, which is expected to be hard to achieve homochiral spin structure for larger $N$ and the values of SHA remain constant irrespective of $N$. The observed SHA invariance indicates that the Pt layers in repetition have a negligible effect on the SHA.

The magnetic exchange interaction is one of the key factors governing the basic characteristics of magnetic systems. In contrast to the symmetric nature of the Heisenberg exchange interaction, the interfacial Dzyaloshinskii-Moriya interaction (DMI) generates an antisymmetric exchange interaction, which offers challenging opportunities in spintronics with intriguing antisymmetric phenomena. The role of the DMI, however, is still under debate, because largely distinct strengths of the DMI have been measured for different magnetic objects, particularly chiral magnetic domain walls (DWs) and nonreciprocal spin waves (SWs). In this paper, by carefully examining the measurement principles, we demonstrate that both the DWs and SWs experience the same strength of the DMI. The key factor in this demonstration is to identify the appropriate experimental conditions by excluding all possible artifacts that causes additional undesired symmetric and antisymmetric contributions in chiral DW dynamics. The present demonstration, therefore, verifies the universality of the DMI between different magnetic dynamics as an intrinsic exchange interaction and also, guarantees the compatibility of several DMI-measurement schemes recently proposed.

To achieve better chemical affinity between conducting polyaniline (PANI) and soft magnetic carbonyl iron (CI) microspheres, we initially attached hydroxyl groups to the surface of CI using p -toluenesulfonic acid monohydrate. The PANI-coated CI composite particles were then fabricated via a chemical oxidation polymerization method. Both the aniline monomer and anilinium cation tended to surround the activated surface of the CI microspheres due to hydrogen bonding and electrostatic interactions, providing a better core-shell shape of the CI/PANI particles. Crystallinity of the product particles and bonding between CI and PANI were measured by X-ray diffraction and FT-IR spectroscopy, respectively, while the shell morphology and thermal stability were measured by scanning electron microscope and thermogravimetric analysis, respectively, confirming the successful coating performance. Viscoelastic behaviors of the MR fluid prepared by suspending the magnetic particles in medium oil were measured via a rotation rheometer under an induced magnetic field. It also exhibited a typical MR flow behavior, which was analyzed using various rheological models. Its sedimentation was detected using a Turbiscan, showing a 60% and 11% improved dispersion stability at 200 min and 900 min, respectively, compared to the pure CI particles by decreasing the density mismatch between composite particle and silicone oil.

Magnetic materials exhibiting perpendicular magnetic anisotropy (PMA) have an important role in the development of high-density magnetic random-access memory and domain-wall devices. Exotic physical phenomena result from spin-orbit coupling, such as PMA and the interfacial Dzyaloshinskii-Moriya interaction (iDMI), at interfaces between nonmagnetic (NM) and ferromagnetic (FM) materials. We report on the NM Pt thickness dependence of PMA and iDMI in Ta/Pt/CoFeSiB/Ta films and the MgO thickness dependence of PMA in Ta/Pt/CoFeSiB/MgO/Ta films. We selected amorphous FM CoFeSiB because of its lower saturation magnetization (560 emu/cm3) than that of Co or CoFeB, which may be beneficial for lowering the current density for switching. All samples were deposited by dc magnetron sputtering and annealed at 300 °C for 1 h. The Ta(3)/Pt(5)/CoFeSiB(1.5)/Ta(5) (nm) film exhibited PMA in the as-deposited state as well as after heat treatment. This structure possessed an iDMI energy density of 0.386 mJ/m2.

We investigate the spin dynamics including Gilbert damping in the ferromagnetic nanowire arrays. We have measured the ferromagnetic resonance of ferromagnetic nanowire arrays using vector-network analyzer ferromagnetic resonance (VNA-FMR) and analyzed the results with the micromagnetic simulations. We find excellent agreement between the experimental VNA-FMR spectra and micromagnetic simulations result for various applied magnetic fields. We find that the demagnetization factor for longitudinal conditions, Nz (Ny) increases (decreases) as decreasing the nanowire width in the micromagnetic simulations. For the transverse magnetic field, Nz (Ny) increases (decreases) as increasing the nanowire width. We also find that the Gilbert damping constant increases from 0.018 to 0.051 as the increasing nanowire width for the transverse case, while it is almost constant as 0.021 for the longitudinal case., Comment: 7 Figures

Magneto-responsive polyaniline (PANI)-coated magnetic carbonyl iron (CI) microspheres were synthesised using a dispersion polymerisation process. The CI particles were initially modified using dopamine as a chemical grafting agent to strengthen the affinity between PANI and the CI particles. The surface morphology of the fabricated core-shell structured particles was confirmed by scanning electron microscopy. The chemical composition of the dopamine-modified CI particles was examined by X-ray energy dispersive spectroscopy, and the magnetic properties of the particles were analysed using a vibrating sample magnetometer. The magnetorheological (MR) characteristics of the CI-PANI particle-based MR fluid dispersed in silicone oil were measured using a rotational rheometer, which exhibited a typical liquid-like to solid-like phase transition. The sedimentation stability of the microspheres was analysed further using a Turbiscan apparatus with better dispersion stability than pure CI particles.

The purpose of this study is to examine implications of pre-service science teacher training by analyzing science field integration and connection between learning content presented in 'Integrated Science' for high school students based on the 2015 revised science curriculum, and in pre-service science learning materials (textbooks) of the college of education. For this study, the 2015 revised 'Integrated Science' curriculum and 11 types of pre-service science teachers' learning materials related to physics, chemistry, biological science, and earth science were selected. The results were as follows. Most of the learning content presented in the 2015 revised 'Integrated Science' curriculum had integrated two or more science fields. Also, almost all learning content presented in the 2015 revised 'Integrated Science' curriculum were included in pre-service science teachers' education content, with educational content for chemistry introduced at the highest rate. The textbooks for pre-service science teachers had the most learning contents of 'Energy and Environment' domain of 'Integrated Science' for high school students. Accordingly, these results suggest that 'integrated science materials' should be developed for proper the curriculum implementation. Also, training courses for science teachers responsible for 'Integrated Science' are required. Furthermore, a revised curriculum for the college of education and a method to link with certification examinations for secondary school teachers are needed.

We investigate the interfacial Dzyaloshinskii-Moriya interaction (iDMI) and the perpendicular magnetic anisotropy (PMA) in the annealed inversion symmetry breaking structures (Pt/Co (CoFeB)/AlO x and Ta/CoFeB/AlO x) by Brillouin light scattering. The iDMI energy density of Pt/Co and Pt/CoFeB samples decreases while increasing annealing temperature, but the iDMI energy density of Ta/CoFeB sample slightly increases by increasing annealing temperature. By applying the thermal annealing process, PMA energies slightly increase at the Pt/Co interface; however, Pt/CoFeB, (Ta/CoFeB) structures are dramatically decreased (increased) by the annealing process. The effects of the annealing show complicate variation for iDMI and PMA for each structure; however, we find overall weak correlations between iDMI and PMA despite different materials and annealing process.

We report systematic measurements of the interfacial Dzyaloshinskii-Moriya interaction (iDMI) by employing Brillouin light scattering in Pt/Co/AlOx and Ta/Pt/Co/AlOx structures. By introducing a tantalum buffer layer, the saturation magnetization and the interfacial perpendicular magnetic anisotropy are significantly improved due to the better interface between heavy metal and ferromagnetic layer. From the frequency shift between Stokes- and anti-Stokes spin-waves, we successively obtain considerably larger iDM energy densities (Dmax-=-1.65-±-0.13 mJ/m2 at tCo-=-1.35-nm) upon adding the Ta buffer layer, despite the nominally identical interface materials. Moreover, the energy density shows an inverse proportionality with the Co layer thickness, which is the critical clue that the observed iDMI is indeed originating from the interface between the Pt and Co layers.

Received 25 March 2015Received in revised form6 May 20151 June 2015Accepted 1 June 2015The purpose of this study is to investigate the learning contents presented in high school science and in pre-service science textbooks of college of education, and to examine educational implications for pre-service science teachers by analysing their connection to each other. High school science is called as ‘convergence science.’ Seven high school science textbooks and eleven science textbooks related to physics, chemistry, biological science, and earth science for pre-service teachers were selected to analyse learning contents. The relationship between high school science with those of college-level science textbooks for pre-service science teachers was found when the learning contents were compared. Science textbooks for pre-service science teachers have the biggest number of learning contents on the chapter ‘Energy and Environment’ of high school science. About 86.6% of learning contents of high school science were introduced on textbooks on science, but pre-service teachers should learn the remainder. The part of learning contents presented in high school science textbooks was higher than the college-level for pre-service science teachers. Moreover, the part of learning contents was included in Engineering & Technology. And these required a special teacher education. Accordingly, the results suggested that learning contents for high school science should be optimized and reduced. Also, various educational programs should be developed and educational curriculum for pre-service science teachers should be revised.

The effect of cooling rate on the thermal stability and soft magnetic properties of [(Fe 0.5 Co 0.5 ) 0.75 B 0.2 Si 0.05 ] 100-x Nb x (x = 5, 6, 7, 8 at. %) system was investigated. The alloys were produced into the form of ribbon and cylindrical rod by melt-spinning and injection casting, respectively. Their structure, thermal, mechanical and soft magnetic properties were investigated by x-ray diffraction, differential scanning calorimetry, universal testing machine and vibrating sample magnetometer, respectively. All of the alloys were identified as fully amorphous by X-ray diffraction. It turned out that the rod samples had exceptionally high saturation fields reaching 3.0 kOe, which is key properties for sensor application. Also, among these Fe,Co-based samples, the Fe 35.25 Co 35.25 B 18.8 Si 4.70 Nb 6 ribbon exhibits the highest saturation magnetization with 142.1 emu/g.

We investigate the role of top and bottom interfaces in inversion symmetry-breaking Pt/Co/AlOx systems by inserting ultra-thin Cu layers. Wedge-type ultrathin Cu layers (0-0.5 nm) are introduced between Pt/Co or Co/AlOx interfaces. Interface sensitive physical quantities such as the interfacial Dzyaloshinskii-Moriya interaction (iDMI) energy density, the interfacial perpendicular magnetic anisotropy (iPMA), and the magneto-optical Kerr effects (MOKE) are systematically measured as a function of Cu-insertion layer thickness. We find that the Cu-insertion layer in the bottom interface (Pt/Co) plays a more important role in iDMI, PMA, and MOKE. In contrast, the top interface (Co/AlOx) noticeably contributes to only PMA, while its contributions to iDMI and MOKE enhancement are less significant. Although the PMA mainly comes from the bottom interface (Pt/Co), the Cu-insertion layers of all interfaces (Pt/Co, Co/AlOx) influence PMA. For iDMI, only the Cu-insertion layer in the bottom interface exerts SOC suppression which leads iDMI energy to decrease rapidly.

The perpendicular magnetic anisotropic property of amorphous CoSiB/Pd multilayers was studied as a function of the thicknesses of the CoSiB and the number of repeated CoSiB/Pd bilayers. In this study, we investigate the effects of thermal annealing on the perpendicular magnetic anisotropic property of the [CoSiB 2, 3, 4, 5 A/Pd 13 A]5 multilayer films. We vary the annealing temperature between from 200 to 350°, with the thicknesses of the CoSiB layer being kept constant. We examine the magnetic properties such as the saturation magnetization and the coercivity. The annealing temperature is closely related to the magnetic property of the CoSiB/Pd multilayers, and the coercivity especially is proportional to the annealing temperature.

We investigated the optical properties of the tris(8-hydroxyquinoline)aluminum (Alq 3 ) organic film with Fabry–Perot microcavity by measuring photoluminescence (PL) and transmittance. We have simulated the phase change on reflection as a function of wavelength. The Fabry–Perot microcavity structures were designed according to the simulation results and the resonant wavelength corresponding to the maximum of PL spectrum of a bare Alq 3 film. These structures were fabricated in three types of microcavities, such as type A [air|metal|Alq 3 |metal|glass], type B [air|dielectric|Alq 3 |dielectric|glass], and type C [air|metal|Alq 3 |dielectric|glass]. A bare Alq 3 layer on glass, [air|Alq 3 |glass], showed a PL peak around 514 nm and its full width at half maximum (FWHM) was about 80 nm. The broad FWHM of the bare Alq 3 film was reduced to 15–27.5, 7–10.5 and 16–16.6 nm for three types by cavity effects. Also, the control of the resonant wavelength can be achieved by the spacer length as well as the phase change on reflection on mirror.