The design and study of pedagogical paper recommendation

For learners engaging in senior-level courses, tutors in many cases would like to pick some articles as supplementary reading materials for them each week. Unlike researchers ‘Googling’ papers from the Internet, tutors, when making recommendations, should consider course syllabus and their assessment of learners along many dimensions. As such, simply ‘Googling’ articles from the Internet is far from enough. That is, learner models of each individual, including their learning interest, knowledge, goals, etc. should be considered when making paper recommendations, since the recommendation should be carried out so as to ensure that the suitability of a paper for a learner is calculated as the summation of the fitness of the appropriateness of it to help the learner in general. This type of the recommendation is called a Pedagogical Paper Recommender.In this thesis, we propose a set of recommendation methods for a Pedagogical Paper Recommender and study the various important issues surrounding it. Experimental studies confirm that making recommendations to learners in social learning environments is not the same as making recommendation to users in commercial environments such as Amazon.com. In such learning environments, learners are willing to accept items that are not interesting, yet meet their learning goals in some way or another; learners’ overall impression towards each paper is not solely dependent on the interestingness of the paper, but also other factors, such as the degree to which the paper can help to meet their ‘cognitive’ goals.It is also observed that most of the recommendation methods are scalable. Although the degree of this scalability is still unclear, we conjecture that those methods are consistent to up to 50 papers in terms of recommendation accuracy. The experiments conducted so far and suggestions made on the adoption of recommendation methods are based on the data we have collected during one semester of a course. Therefore, the generality of results needs to undergo further validation before more certain conclusion can be drawn. These follow up studies should be performed (ideally) in more semesters on the same course or related courses with more newly added papers. Then, some open issues can be further investigated. Despite these weaknesses, this study has been able to reach the research goals set out in the proposed pedagogical paper recommender which, although sounding intuitive, unfortunately has been largely ignored in the research community. Finding a ‘good’ paper is not trivial: it is not about the simple fact that the user will either accept the recommended items, or not; rather, it is a multiple step process that typically entails the users navigating the paper collections, understanding the recommended items, seeing what others like/dislike, and making decisions. Therefore, a future research goal to proceed from the study here is to design for different kinds of social navigation in order to study their respective impacts on user behavior, and how over time, user behavior feeds back to influence the system performance

Phase Noise of Nanoelectromechanical Systems

Nanoelectromechanical systems (NEMS) are microelectromechanical systems (MEMS) scaled down to nanometer range. As the size of the NEMS resonators is scaled downward, some fundamental and nonfundamental noise processes will impose sensitivity limits to their performance. In this work, we first present theory of phase noise mechanism of NEMS to examine both fundamental and nonfundamental noise processes. Fundamental noise processes considered here include thermomechanical noise, momentum-exchange noise, adsorption-desorption noise, diffusion noise, and temperature-fluctuation noise. For nonfundamental noise processes, we develop a formalism to consider the Nyquist-Johnson noise from transducer-amplifier implementations. As an initial step to experimental exploration of these noise processes, we describe and analyze several phase-locked loop schemes based on NEMS at very high frequency and ultrahigh frequency bands. In particular, we measure diffusion noise of NEMS arising from xenon atoms adsorbed on the device surface using the frequency modulation phase-locked loop. The observed spectra of fractional frequency noise and Allan deviation agree well with the prediction from diffusion noise theory. Finally, NEMS resonators also provide unprecedented sensitivity for inertial mass sensing. We demonstrate in situ measurement in real time with mass floor of ~20 zg. Our best mass sensitivity corresponds to ~7 zeptograms, equivalent to ~30 xenon atoms or the mass of an individual 4 kDa molecule. Detailed analysis of the ultimate sensitivity of such devices based on these experimental results indicates that NEMS can ultimately provide inertial mass sensing of individual intact, electrically neutral macromolecules with single-Dalton sensitivity.</p

Observations and Analysis of High-Resolution Magnetic Field Structures in Molecular Clouds

Recent high-angular-resolution (up to 0.7") dust polarization observations toward star forming regions are summarized. With the Sub-Millimeter Array, the emission from the dense structures is traced and resolved. The detected magnetic field morphologies vary from hourglass-like structures to isolated patches depending on the evolutionary stage of the source. These observed features have also served as a testbed to develop new analysis methods, with a particular focus on quantifying the role of the magnetic field in the star formation process.Comment: 4 pages, 2 figures; To appear in Proceedings of Magnetic Fields in the Universe: From Laboratory and Stars to Primordial Structures Aug. 21st - 27th 2011, Zakopane, Poland Eds. M. Soida, K. Otmianowska-Mazur, E.M. de Gouveia Dal Pino & A. Lazaria

Supervisor Perceptions of Their Multicultural Training Needs for Working with English Language Learning Supervisees

The counselor education and supervision profession has embraced the need to prepare multiculturally competent supervisors (American Counseling Association, 2005; Bernard & Goodyear, 2013; Inman & Ladany, 2014). However, literature dealing with training supervisors to work with linguistically diverse supervisees is limited and supervisors\u27 training needs for effectively supervising linguistically diverse supervisees are not yet clearly addressed. The aim of this qualitative study was to develop a theory which explained supervisors\u27 perceptions of their multicultural training needs for working with English language learning supervisees. Constructivist grounded theory was utilized in this effort to analyze the data gathered from 10 supervisors who speak English as their first language and are providing clinical supervision in a CACREP program. Three superordinate themes as well as five themes and 17 subthemes were constructed and explained. The first superordinate theme, institutional level, had one theme emerge, which was institutional change. Institutional change involved two subthemes: improve infusion of competence with ELL in CACREP Standards and enhance advocacy for ELLs. The second superordinate theme that emerged was professional collaboration. One theme under this superordinate theme was enhanced collaboration. The third superordinate theme involved supervisor competence. The theme in this area included multicultural awareness, multicultural knowledge, and multicultural skills. Multicultural awareness involved six subthemes: awareness of increasing numbers and diversity of ELLs, recognize challenges and opportunities presented by linguistic differences, recognize probable similarities, recognize power differential, recognize cognitive complexity required for bicultural (or polycultural) competence, and understand languages are not semantically equivalent. Multicultural knowledge involved three subthemes: have a framework or have evidence-based knowledge to work with ELL supervisees, distinguish levels of acculturation, and knowledge of ELL cultures. Multicultural skills had five subthemes emerge. These subthemes were navigate dual language relationships, employ multicultural counseling skills in supervising ELLs, assess communication styles and outcomes, supervisors and supervisees are both teachers and learners, and facilitate parallel process. Possible implications of this research and suggestions for future study were provided

Identifying and Evaluating the Universe of Outlets for Information Systems Research: Ranking the Journals

We use a survey instrument to identify the universe of journal publication outlets for information systems (IS) research, to identify the IS journals, and to observe the value of the outlets to IS researchers. In an online survey we asked IS researchers to rate the value of IS publication outlets and to categorize them into IS journals, allied discipline journals, and professional and managerial magazines and journals. 1129 validated and non-duplicate respondents rated 326 journals, which we present in three rank-ordered lists, one for each of IS journals, allied discipline journals, and professional and managerial magazines and journals. In addition, we graphically present trends in the ranking of five selected journals from 1991 through 2003. This is the first attempt to identify the universe of IS journal publishing outlets, the first to rank the value of IS journals separately, and the first attempt to rank the value of IS publication outlets without pre-selecting the set of journals to be ranked

Electro-diffusion in a plasma with two ion species

Electric field is a thermodynamic force that can drive collisional inter-ion-species transport in a multicomponent plasma. In an inertial confinement fusion (ICF) capsule, such transport causes fuel ion separation even with a target initially prepared to have equal number densities for the two fuel ion species. Unlike the baro-diffusion driven by ion pressure gradient and the thermo-diffusion driven by ion and electron temperature gradients, electro-diffusion has a critical dependence on the charge-to-mass ratio of the ion species. Specifically, it is shown here that electro-diffusion vanishes if the ion species have the same charge-to-mass ratio. An explicit expression for the electro-diffusion ratio is obtained and used to investigate the relative importance of electro- and baro-diffusion mechanisms. In particular, it is found that electro-diffusion reinforces baro-diffusion in the deuterium and tritium mix, but tends to cancel it in the deuterium and helium-3 mix.Comment: Submitted to Phys. Plasmas on 2012-03-06 (revised version 05/13/2012