Research has shown that using debate in higher education as a pedagogical tool has effect on promoting higher order and critical thinking (Camp & Schnader, 2010; Ng et al., 2004; Roy & Macchiette, 2005; Ryan & College, 2006). Debate has been implemented in various disciplines with adult learners, such as psychology (Budesheim & Lundquist, 1999), medicine (Koklanaris, Mackenzie, Fino, Arsland, & Seubert, 2008 ), political science (Omelicheva, 2005), marketing (Roy & Macchiette, 2005), accounting (Camp & Schnader, 2010), science & technology (Scott, 2008). Based on the previous studies, students viewed the use of debate as a new and innovative way to teaching and learning, while being more informative, and eye-opening (Kennedy, 2009; Munakata, 2010). The non-traditional method of teaching also increased students motivation and interest level (Munakata, 2010) as it gave a real sense of drama (Roy & Macchiette, 2005, p. 271). However, in teacher preparation, the implementation of debate as a pedagogical tool to promote learning as well as the research on this topic is relatively limited (Erduran, Ardac, & Yakmaci-Guzel, 2006; Ng, Lan, & They, 2004; Munakata, 2010; Sadler, 2006).  This study aims to implement debate as pedagogical tool to enhance pres-service teachers learning on the subject matter and investigate the effect of using debate in teacher training in Singapore context. The following research questions were posed in the study: (1) whether debate stimulated students thinking on the subject matter more than textbook readings and lectures (traditional teacher-directed methods), (2) to which extent students found debate helpful to their learning on the subject matter, (3) to which extent debate helped students to make connections between the subject matter and the real life, and (4) what was the qualitative feedback from students in their learning through the debate activity. Fifty-six pre-service teachers participated in a course evaluation survey to provide feedback on their learning. The results have shown that 83.9% of teachers agree that debate stimulated their thinking more than textbook readings and lectures, while 14.3% of teachers felt neutral, and 1.8% of teachers strongly disagree. Eighty two percent of teachers found debate very helpful to their learning while 16.1% felt neutral. In addition, 80.4% of teachers agree that debate helps them to make connections between the subject matter and the real life experiences while 17.9% of teachers felt neutral. Several observations emerged from students qualitative feedback on using debate in learning. Students expressed that the debate activity helped them to expand the understanding of the subject matter, retention of crucial concepts and knowledge, and comprehension of essential issues on the subject matter. Students felt debate helped them to understand different perspectives, and reduce bias. Some students reported change of their positions and perspectives after the debate. More importantly, many students stated that debate helped them develop critical thinking and higher order thinking skills in comparison to traditional methods.

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The drain-induced barrier lowering (DIBL) effect in 4H-SiC MESFETs has been studied using the physical drift and diffusion model. Our simulation results showed that the high drain voltage typically applied in short-channel 4H-SiC MESFETs could substantially reduce the channel barrier and result in large threshold voltage shift. It is also found that the DIBL effect is more dependent on the ratio of the gate length to channel thickness (Lg/a), rather than the channel thickness itself. In order to minimize the DIBL effect, the ratio of Lg/a should be kept greater than 3 for practical 4H-SiC MESFETs.

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We study light trapping and parasitic losses in hydrogenated amorphous silicon thin film solar cells fabricated by plasma-enhanced chemical vapor deposition on nanostructured back reflectors. The back reflectors are patterned using polystyrene assisted lithography. By using O2 plasma etching of the polystyrene spheres, we managed to fabricate hexagonal nanostructured back reflectors. With the help of rigorous modeling, we study the parasitic losses in different back reflectors, non-active layers, and last but not least the light enhancement effect in the silicon absorber layer. Moreover, simulation results have been checked against experimental data. We have demonstrated hexagonal nanostructured amorphous silicon thin film solar cells with a power conversion efficiency of 7.7% and around 34.7% enhancement of the short-circuit current density, compared with planar amorphous silicon thin film solar cells.