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Quantitative analysis of the electric dipole on finite sized graphite sheets
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| Pengarang | : | David Groh |
| Nama Majalah/Jurnal | : | American Journal of Physics |
| Volume / Edisi | : | 77 (No. 12) |
| Halaman | : | 1107-1111 |
| Abstrak | : | Graphite sheets are commonly used in introductory physics laboratories to model electric potential patterns for systems such as dipoles and parallel plates. Usually, silvered ink pens are used to draw patterns on the sheets and appropriate voltages are then applied. Quantitative experiments are often done at the intermediate level. Students are often puzzled by the failure of the patterns to confirm to the theoretical figure in the manual that came with the kit. I discuss measuring difficulties and some of the common theoretical methods for analyzing edge effects on the sheets. |
On thermionic emission and the use of vacuum tubes in the advanced physics laboratory
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | American Journal of Physics |
| Volume / Edisi | : | 77 (No. 12) |
| Halaman | : | 1102-1106 |
| Abstrak | : | Two methods are outlined for measuring the charge-to-mass ratio of the electron using thermionic emission as exploited in vacuum tube technology. One method employs the notion of the space charge in the vacuum tube diode as described by the Child–Langmuir equation; the other method uses the electron trajectories in vacuum tube pentodes with cylindrical electrodes under conditions of orthogonally related electric and magnetic fields (the Hull magnetron method). The vacuum diode method gave (averaged over the vacuum diodes studied), and the Hull magnetron method gave (averaged over both pentodes and the anode voltages studied). These methods afford opportunities for students to determine the ratio without using the Bainbridge tube method and to become familiar with phenomena not normally covered in a typical experimental methods curriculum. |
A water wave analog of the Casimir effect
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | American Journal of Physics |
| Volume / Edisi | : | 77 (No. 12) |
| Halaman | : | 1095-1101 |
| Abstrak | : | Two rigid plates are vertically suspended by thread such that they are parallel to and opposite each other. The plates are partially submerged in a dish of liquid that is attached to the top of a vertical shake table. When the shake table is driven with noise in a frequency band, random surface waves are parametrically excited, and the plates move toward each other. The reason for this attraction is that the waves carry momentum, and the wave motion between the plates is visibly reduced. The behavior is analogous to the Casimir effect, in which two conducting uncharged parallel plates attract each other due to the zero-point spectrum of electromagnetic radiation. The water wave analog can be readily demonstrated and offers a visual demonstration of a Casimir-type effect. Measurements of the force agree with the water wave theory even at large wave amplitudes, where the theory is expected to break down. The water wave analog applies to side-by-side ships in a rough sea and is distinct from the significant attraction that can be caused by a strong swell. |
Corpora, Locally Sourced: An Approach to Addressing the Specific Needs of ESL Writing Programs
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Tesol Quarterly |
| Volume / Edisi | : | 58 (No. 3) |
| Halaman | : | 1215-1226 |
| Abstrak | : | This paper discusses the development and implementation of a locally-sourced corpus to address the specific needs of an ESL writing program. The paper begins with a description of the motivation and development of the Corpus of Ohio Learner and Teacher English (COLTE), a large in-house corpus consisting of assessed ESL student writing and teacher feedback from first-year writing courses. The paper illustrates research conducted within the local context using the COLTE and discusses how the program's corpus-based approach influenced curricular revisions and instructional practice. It addresses the evaluation of these efforts, challenges encountered, and considerations for building and using corpora at the program level. The paper concludes by arguing that stakeholders within programs can work collaboratively to build and use locally-sourced corpora grounded in their specific setting to explore local practices and address the English language learning and teaching needs of their own particular context. |
Benefits and Challenges of Using Do-it-yourself Corpora for Academic Writing Development
| Pengarang | : | Charles, Maggie |
| Nama Majalah/Jurnal | : | Tesol Quarterly |
| Volume / Edisi | : | 58 (No. 3) |
| Halaman | : | 1205-1214 |
| Abstrak | : | The term "do-it-yourself (DIY) corpora" is used here to refer to cor-pora that are compiled by students for their own use, specifically in academic writing. Students may investigate their custom-built corpus of expert texts for language features such as vocabulary, collocations, discourse structure, rhetorical functions, or language patterns and they may examine a corpus of their own texts for editing and revising purposes. This paper first presents the theoretical underpinnings of DIY cor-pus-building and reviews the literature before discussing some of the benefits and challenges of the approach. It concludes with some prac-tical considerations for would-be adopters. |
Expanding Methodological Approaches in DDL Research
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Tesol Quarterly |
| Volume / Edisi | : | 58 (No. 3) |
| Halaman | : | 1193-1204 |
| Abstrak | : | This paper analyses the methodologies in 148 empirical data-driven learning studies for L2 English in prestige journals to examine best practice. Manual coding and corpus analysis of key words and n-grams from the past 5 years (2018–2022) explore the field as a whole and how methodologies have evolved, suggesting improvements and future avenues for research. |
Corpora in English Language Teacher Education: Research, Integration, and Resources
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Tesol Quarterly |
| Volume / Edisi | : | 58 (No. 3) |
| Halaman | : | 1181-1192 |
| Abstrak | : | For some time, arguments have been made that for the increased successful use of corpus linguistics (CL), in the form of Data-Driven Learning (DDL; Johns, 1991) in the second language classroom, teacher education programs must play a central role by providing the necessary instruction and triggers. Three means of integrating corpora into teacher education have been identified (Le?ko-Szyma?ska, 2022): as a tool for language awareness, as pedagogically-focussed instruction for DDL, and as a fully-fledged CL course. It is difficult to gauge the effectiveness of these three approaches because we can only rely on the relatively few, but growing, number of research studies that are published. Naturally, the existing studies are based on relatively small numbers of participants, rely mainly on data collected through questionnaires and self-reports, and rarely trace the extended effects of the instruction after the student teachers leave the programs. It is also hard to generalize from these accounts as they are deeply imbedded in their institutional curricula and their local teacher education traditions. Nonetheless, they provide a foundation for the discussion in this paper which proposes a tripartite framework for the integration of instructional CL into language teacher education programs. This consists of corpus literacies, corpus-based language pedagogy, and corpus-based reflective practice. In addition, we present a summary of some useful published resources that can be used to support the integration of such a framework. |
Learner Corpora in Corpus-Informed Instruction: Moving Toward an Asset- and Genre-Based Model
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Tesol Quarterly |
| Volume / Edisi | : | 58 (No. 3) |
| Halaman | : | 1166-1180 |
| Abstrak | : | Learner corpora have been used extensively in corpus research to identify gaps and errors within learner writing but have rarely been directly used in corpus-informed instruction (CII). Importantly, scholars in CII have pointed out that “it is as important to see what learners can do as well as what they can't” when using learner corpora (Boulton & Thomas, 2012; p. 13). Learner corpora can also offer greater alignment with the genres students are writing (Seidlhofer, 2002). In our Brief Report, we take up Lu, Casal, and Liu's (2021) call for greater synergy of genre and corpus pedagogy by examining the impact of using a learner corpus to enhance students' language awareness and genre-specific knowledge within an English as an Additional Language (EAL) first-year writing classroom. We also move beyond error analysis to encourage an asset-based model to learner CII (Staples, 2022). |
Creating Anti-Oppressive Digital Spaces for Social Justice Language Education
| Pengarang | : | Hart, Deniz Ortactepe |
| Nama Majalah/Jurnal | : | Tesol Quarterly |
| Volume / Edisi | : | 57 (No. 1) |
| Halaman | : | 285-297 |
| Abstrak | : | Contemporary moves towards social justice education and digital pedagogies require language educators to examine the ways digital learning platforms reinforce economic, social, and cultural inequities, and to explore how to instead offer anti-oppressive pedagogies for diverse online communities. In this Teaching Issues essay, I draw from the principles of critical pedagogy to argue that non-linear, non-modular and multimodal digital learning platforms created on content-management systems (CMS) can provide anti-oppressive pedagogical affordances for 1) dismantling teacher-student power relations, 2) cultivating a sense of a digital learning community, and 3) promoting intersectionality within language teacher education programs. Next, I present a discussion of the challenges involved in designing an anti-oppressive, transformative digital learning space, and of several critical questions teacher educators can reflect upon while designing their own virtual environments. |
Developing Preservice Bilingual Teachers’ Transformative Agency
| Pengarang | : | Chang, Sharon |
| Nama Majalah/Jurnal | : | Teaching and Teacher Education |
| Volume / Edisi | : | 137 (No. 137) |
| Halaman | : | 1–10 |
| Abstrak | : | U.S. bilingual educators struggle with English hegemonic ideology and inadequate ethnolinguistic resources. Using the theoretical framework of transformative agency by double stimulation, this qualitative case study investigated how preservice Chinese and Spanish bilingual teachers actively confronted such struggles during their practicum experiences to improve their culturally responsive pedagogies. Four types of warping actions were found: amplifying bilingual instruction, formulating support for bilingual learning, generating new bilingual pedagogical knowledge, and taking charge of their own professional growth as bilingual teachers. The study concludes that preservice teachers’ transformative agency can be pedagogically facilitated with mediational tools offered through formative intervention research methods. (100 words). |