Alexandros XafopoulosUniversity College London | UCL · Institute of Education
Alexandros Xafopoulos
MA EduTech (UCL, UK), BSc CompSci, BTh (AUTh, GR)
+ Leading a Python & Coding Support Team with 7.5K+Joins
+ https://discord.gg/8NWMugHkzm
About
17
Publications
20,141
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77
Citations
Introduction
+Private Online Univ. Python Tutor - IDSP Founding Coordinator & Facilitator - MA EduTech Grad from UCL IOE, UK - CompSci & Theo Grad (1st) from AUTh, GR - Past Scholar of IKY, OTE, & Research Committee of AUTh - Past Researcher-Programmer @ AIIA lab of AUTh - Past Visiting Researcher @ TICSP, FI - 2 Chapter, 2 Elsevier Journal, & 4 Conf. peer-reviewed Papers - 4 Conf. Presentations, 2 acad. Seminar Talks - ~95 Cits. - Research interests in Programming & E-Learning.
Additional affiliations
June 2016 - October 2016
August 2015 - present
Alexandros' Tuition
Position
- Private Online University Programming Tutor
Description
- Tutoring undergraduates, postgraduates, & professionals mainly in Python & Java.
August 2001 - August 2001
Education
September 2014 - August 2017
December 2002 - July 2014
September 1995 - January 2000
Publications
Publications (17)
This chapter investigates the highly researched and debated key issue of electronic collaboration (e-collaboration) in the learning process, onwards called e-collaborative learning (e-CL), in a holistic overview. The structure of the chapter is as follows. First of all, it clarifies the meaning and context of e-CL, and compares it with analysed rel...
This paper deals with language identification in the domain of web documents. The proposed system is built on hidden Markov models (HMMs) that enable the modeling of character sequences. Furthermore, the use of HMMs provides the means for language tracking, that is, language identification across the segments of a multilingual document.
This paper investigates the way that electronic collaborative learning (e-CL) affords the learning process regarding human, pedagogy, content, and framework aspects. By e-CL the communicative shared-knowledge building process with shared-knowledge building goals using networked electronic devices is denoted. As for the human aspect, e-CL enables tu...
Outline: • Framework • Preprocessing - • Features (Extraction, Noise Compensation-Channel Equalization, Selection) • Matching - Modeling • Decision Making - • Performance Evaluation • Experimental Results • References
This study investigates the Systems Thinking Approach to Educational Technology (STAET) in China and contrasts it with its rival academic view for Educational Technology known as Electrifying Education (EE). Although the two views share the same goal, to optimise the learning process in the education system, their basic difference is the different...
This chapter investigates the highly topical issue of electronic collaborative learning (e-CL) in a holistic overview. First of all, a clarification of the term and context of e-CL is provided comparing it with similar concepts. Second, the human elements and communities of e-CL are examined, together with their roles and aspects. Third, the suppor...
This article investigates the highly topical issue of electronic collaborative learning (e-CL) in a holistic overview. First of all, a clarification of the term and context of e-CL is provided comparing it with similar concepts. Second, the human elements and communities of e-CL are examined, together with their roles and aspects. Third, the suppor...
This chapter investigates the highly researched and debated key issue of electronic collaboration (e- collaboration) in the learning process, onwards called e-collaborative learning (e-CL), in a holistic overview. The structure of the chapter is as follows. First of all, it clarifies the meaning and context of e-CL, and compares it with analysed re...
This study suggests a supportive Computer Programming tutoring scheme at the UCL Computer Science Department for undergraduates facing serious programming challenges. The kinds of the latter challenges are investigated and a tutoring scheme based on these is designed. The scheme is supported and funded by the UCL ChangeMakers initiative. This effor...
The self-organizing map algorithm has been used successfully in document organization. We now propose using the same algorithm for document retrieval. Moreover, we test the performance of the self-organizing map by replacing the linear Least Mean Squares adaptation rule with the marginal median. We present two implementations of the latter variant...
Automatic language identification in written text documents is an issue which deserves significant attention in the context of the ever-growing volume of web documents. This paper deals with language identification in the domain of electronic texts related to tourism. The proposed system is built on Hidden Markov Models (HMMs) that enable the model...
Automatic language identification in written text documents is an
issue which deserves significant attention in the context of the ever-growing
volume of web documents. This paper deals with language identification
in the domain of electronic texts related to tourism. The proposed
system is built on Hidden Markov Models (HMMs) that enable the model...
Three simple speaker verification techniques based on vector quantization, sphericity models and dynamic time warping, respectively, are developed and tested using the same experimental protocol. Two types of feature vectors, the linear prediction derived cepstral coefficients and the mel-frequency cepstral coefficients are considered. The efficien...
In this paper we present a method for document organization and retrieval based on statistical language modeling. The proposed method, which is based on the vector model, uses nonlinear interpolation to provide more accurate statistical estimators of the conditional probabilities employed for encoding the context of each word. An information retrie...
Outline: • Framework • Preprocessing - • Features (Extraction, Noise Compensation-Channel Equalization, Selection) • Matching-Modeling • Decision Making - • Performance Evaluation • Experimental Results • References
A variant of the WEBSOM architecture for information retrieval is proposed in this paper. WEBSOM is based on the self-organizing map that employs a linear LMS adaptation rule for updating the weight vector of each neuron. Accordingly, the weight vector converges asymptotically to the conditional cluster mean of the feature vectors assigned to the c...
This thesis is a 3D approach of the broad scientific field of automatic speaker recognition.
-In breadth: by presenting its relation with other relative scientific fields and noting its kinds.
-In length: by presenting the stages of the procedure and its mathematical and algorithmic background.
-In depth: by presenting a practical application with...
Questions
Questions (12)
+Greetings. I have recently completed a Master's dissertation at UCL entitled 'Path Analysis of Student Engagement and Performance in an Online Postgraduate Course', being a small-scale quantitative research project in about 25,000 words. Please offer me your suggestion on potential publishers. Many thanks.
+Greetings. I have recently submitted an edited book proposal to IGI Global entitled 'Structural Equation Modelling in Digital Higher Education'. Please let me know if one of you or someone you know would be interested in being the second editor. Many thanks.
+Welcome.
The human person appears to have a linking power, which enables the person to link to the functions of another living being. Following are some attributes of these linking functions or links.
Regarding the kind of functions the links can be made to functions of living beings, such as controlling, conceptualising, knowing, reasoning, speaking, emotion feeling, wanting, sensing (seeing, hearing, smelling, tasting, touching), moving & living.
Regarding place the links can be made on-site or in a distance.
Regarding time in the same or in a different time, that is past or future.
Regarding the quantity of outgoing links multiple links can be made in the same time in pseudo-parallel using a kind of context switching between them.
Regarding the quantity of incoming links links can be made to 1, some or all of the functions of the other being.
Regarding the kind of the target the links can be made to the same or to a different being.
The whole scenery in a great degree resembles & reminisces about several technological appliances & their functions, mainly computers & their networks, videoconferencing, television, telephone and others.
The human history is full of examples of activations of these linking functions.
The major challenge & question is how & when these linking functions are activated.
Please share your opinion, experience or references as regards the above reasoning so that it is improved.
Thank you.
[ Featured references:
]
+Welcome.
Total physical response (TPR) [1] & Suggestopedia [2], developed by J. Asher & G. Lozanov respectively, are two teaching methods used mostly in language education. The first employs physical learning activities & realia, whereas the second peripheral learning, trust & baroque music.
Please share with us a) your experience, direct or indirect providing any results, or b) opinion, e.g. advantages, disadvantages, comparisons, propositions, predictions, or c) interesting references, with respect to the above two methods.
You may also consider the following questions:
Under what circumstances are these techniques more effective?
Could these techniques be applied to support bilingual or multilingual education?
How could technology assist the implementation of these methods?
Could these techniques be effectively applied to educational fields other than language?
Thank you.
[ Featured references:
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+Welcome.
Robots can support education in terms of both teaching & learning.
First, in teaching they can be t1) teachers, t2) teacher assistants, t3) teacher programmable objects, that is constructed in hardware, or programmed in software, or t4) a combination. A key research area in this approach is the creation of robots resembling humans physically, mentally and emotionally. [1] (Educational robots)
Second, in learning they can also be l1) students, l2) student assistants, l3) student programmable objects or l4) a combination. [2] (Educational robotics) As students they could be involved in team learning activities or even VLEs/LMSs & virtual worlds. (New? proposal)
Please share with us a) your experience, direct or indirect providing any results, or b) opinion, e.g. advantages, disadvantages, comparisons, propositions, predictions, or c) interesting references, with respect to the above three perspectives.
Thank you.
[ Featured references:
4. http://www.scientificamerican.com/article/4-robots-that-teach-children-science-and-math-in-engaging-ways/ (Abedallah)
]
+Virtual worlds [1] can be defined as interactive 3D virtual environments, where the users take the form of visible avatars. They can support collaborative education.
What is more, they can be used with VLEs/LMSs, as in the case of the Sloodle project, aiming to combine Second Life with moodle, that is two of the mostly used environments in the realms of virtual worlds & VLEs/LMSs respectively.
Please share your experience, direct or indirect, or opinion, e.g. advantages, disadvantages, predictions, or interesting references, with respect to the above.
Please share with us a) your experience, direct or indirect providing any results, or b) opinion, e.g. advantages, disadvantages, comparisons, propositions, predictions, or c) interesting references, with respect to the above three perspectives.
You may consult [2].
Thank you.
[ Featured references:
3. http://eprints.usq.edu.au/21389/ (Lindy)
]
+Welcome.
The Jigsaw teaching technique [1] supports team learning & empathy by engaging all students in two kinds of groups given a topic. First, the topic is segmented into N aspects or parts. Second, the students in their, one out of N, expert group focus on one aspect of the topic. Third, in their jigsaw group they learn all aspects of the topic. As in a jigsaw puzzle, each piece, that is each student's part, is essential for the completion of the process.
The e-Jigsaw could be the online, or even blended, implementation of this technique.
Please share with us your experience or opinion or interesting references with regard to this technique considering also the following questions:
Could you mention any implementations of the technique?
At which ages is this technique more effective?
How can technology support or complement, as e-Jigsaw, this technique?
Could this technique be analysed into categories?
Thank you.
[ Featured references:
3. http://www.jigsaw.org/#steps (Shanthi)
]
+Welcome.
Having as a guide the 'Berlin Model' ('Berliner Modell' in German) [1] & the 'ADDIE Model' [2] of the instructional process please share your opinion or experience or interesting references on any of the following questions.
Which factors of the instructional process, being 2 conditional & 4 decisional according to the 'Berlin Model', & which of its design phases, being 5 according to the 'ADDIE Model', have been mostly impacted by technology?
How has technology impacted each of these factors & design phases?
You may consult [3] (SAMR model), [4, § Introduction], [5, § Features of Online Learning Environment], [6] (Trialogical learning model), [7] (TPACK model), [8] (R2D2 model).
Which model could be more suitable than the 'Berlin Model', as regards the correlated factors, & the 'ADDIE Model', as regards the design phases, of the instructional process?
Thank you.
[ Featured references:
9. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3725874/ (Russell)
]
+Welcome.
The instructional approaches could be classified in terms of the conditional factors place & time as well as other factors.
Firstly, as regards place they can be implemented P1) in a classroom, called face-to-face (F2F), P2) in a distance, called online or virtual or distant, which can be further discriminated into P2a) long distance & P2b) short distance ones or P3) both in a classroom & in a distance (either in parallel or in different occasions), called blended or hybrid.
Secondly, regarding time they can be implemented T1) in the same time, called synchronous or live or real-time, T2) in different time, called asynchronous or on demand & T3) both in the same & in different time (in parallel or in different occasions), which let be called semi-synchronous.
Thirdly, with regard to other factors (such as manner, goal & content) there are numerous further classifications, e.g. open or not, which are out of the scope of this question.
Finally, from the combination of the above result 9 main alternatives: 1) F2F synchronous, i.e. on-site classes, 2) long distance synchronous, i.e. Web live classes, e.g. with videoconferencing or instant messaging, 3) long distance asynchronous, e.g. Web blogs, forums or wikis, 4) long distance semi-synchronous, e.g. MOOCs, 5) short distance synchronous, i.e. intranet live classes, 6) short distance asynchronous, e.g. intranet blogs, forums or wikis, 7) short distance semi-synchronous, e.g. VLEs/LMSs, 8) blended synchronous, i.e. both on-site & online classes & 9) blended semi-synchronous, e.g. both on-site classes & VLEs/LMSs or flipped classes.
Please share your opinion or remarks on the above classification so that it is improved.
Thank you.
+Welcome.
Code-switching [1] can be defined as the alternation between languages or dialects in speaking or writing in a grammatically overall consistent manner. It usually appears in 3 types, that is extrasentential, intrasentential or intraword.
Although it was previously considered as a lower level use of language, lately it is scholarly regarded a normal, natural or even beneficial phenomenon in bilingual or multilingual environments and societies, especially in education and language teaching. There are also those who advocate that not only should it be used as a strategy [2] but also taught as a goal, for example a communicative skill or competence [3].
Please share with us your experience with or opinion on or interesting references to the use of code-switching in education.
Thank you.
[ Featured references:
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+Welcome.
Assistive technology [1] can be defined as the technology used to assist people with disabilities. This question explores the effectiveness of assistive technology used in collaborative environments, which may be called collaborative assistive technology, and especially VLEs/LMSs, such as moodle.
Please consider making reference to 1) the kind of special education, 2) the name of VLE/LMS you consider, 3) whether it is an adapted conventional VLE/LMS or an ad hoc developed from scratch 4) anything else you consider noteworthy (e.g. characteristics of the whole setting, assessments, comparisons, results) & 5) interesting references.
Thank you.
[ Featured references:
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+Welcome.
Educational e-portfolio [1] applications facilitate students' reflection on their learning or courses. Through this reflection learning is supported. This approach is referred to as 'learning through reflection'. Please answer to any of the following questions beginning with the first ones.
Which educational e-portfolio web applications have you used or learned about? Could you provide a ranking or suggestion? Which is their type, for example commercial, open source or ad hoc? Do they feature interoperability with VLEs/LMSs? Do they offer social networking? What does their content management system provide (blogs, resumes, file management, views)?
You may also provide any interesting references.
Thank you.
[ Featured references:
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