Evidence for the weak steric hindrance scenario in the supercooled-state reorientational dynamics

We use molecular-dynamics computer simulations to study the translational and reorientational dynamics of a glass-forming liquid of dumbbells. For sufficiently elongated molecules the standard strong steric hindrance scenario for the rotational dynamics is found. However, for small elongations we find a different scenario -- the weak steric hindrance scenario -- caused by a new type of glass transition in which the orientational dynamics of the molecule's axis undergoes a dynamical transition with a continuous increase of the non-ergodicity parameter. These results are in agreement with the theoretical predictions by the mode-coupling theory for the glass transition.Comment: 4 pages, 3 figures, Phys. Rev. Lett. in pres

Dynamics in a supercooled liquid of symmetric dumbbells: Reorientational hopping for small molecular elongations

We present extensive molecular dynamics simulations of a liquid of symmetric dumbbells, for constant packing fraction, as a function of temperature and molecular elongation. For large elongations, translational and rotational degrees of freedom freeze at the same temperature. For small elongations only the even rotational degrees of freedom remain coupled to translational motions and arrest at a finite common temperature. The odd rotational degrees of freedom remain ergodic at all investigated temperature and the temperature dependence of the corresponding characteristic time is well described by an Arrhenius law. Finally, we discuss the evidence in favor of the presence of a type-A transition temperature for the odd rotational degrees of freedom, distinct from the type-B transition associated with the arrest of the translational and even rotational ones, as predicted by the mode-coupling theory for the glass transition.Comment: 4 pages, 3 figure

Additive bases arising from functions in a Hardy field

A classical additive basis question is Waring's problem. It has been extended to integer polynomial and non-integer power sequences. In this paper, we will consider a wider class of functions, namely functions from a Hardy field, and show that they are asymptotic bases.Comment: 11 pages, reference problem fixe

Compatibility between Text Mining and Qualitative Research in the Perspectives of Grounded Theory, Content Analysis, and Reliability

The objective of this article is to illustrate that text mining and qualitative research are epistemologically compatible. First, like many qualitative research approaches, such as grounded theory, text mining encourages open-mindedness and discourages preconceptions. Contrary to the popular belief that text mining is a linear and fully automated procedure, the text miner might add, delete, and revise the initial categories in an iterative fashion. Second, text mining is similar to content analysis, which also aims to extract common themes and threads by counting words. Although both of them utilize computer algorithms, text mining is characterized by its capability of processing natural languages. Last, the criteria of sound text mining adhere to those in qualitative research in terms of consistency and replicability

‘Peer Critique’ in Debate: A Pedagogical Tool for Teaching Architectural Design Studio

Post-digital architectural education aims to empower future architects by developing open-mindedness and technical skills for the design of non-standard spatial configurations. Students can learn through exploration and experimentation, using three-dimensional graphic design software to generate initial designs and quality feedback, with a mixed model of peers and panel judges assessing final projects. Ratings of individual contributions and performance are commonly found in literature on peer assessment, but qualitative comments from peers can also provide good information on strengths and weaknesses. This study shows that peer critique in the form of debate can be an effective pedagogical tool for educators to provide quality feedback to the presenting group. This paper explores how architecture students responded to this method in a design studio for a master’s degree in architecture in a university in Hong Kong. Interviews were audio-recorded, transcribed and subsequently analysed using the coding system of qualitative software NVivo 11. The responses of the students were positive, although they experienced differences in feedback from different stakeholders

Szemer\'edi's theorem in the primes

Green and Tao famously proved in 2005 that any subset of the primes of fixed positive density contains arbitrarily long arithmetic progressions. Green had previously shown that in fact any subset of the primes of relative density tending to zero sufficiently slowly contains a 3-term term progression. This was followed by work of Helfgott and de Roton, and Naslund, who improved the bounds on the relative density in the case of 3-term progressions. The aim of this note is to present an analogous result for longer progressions by combining a quantified version of the relative Szemer\'edi theorem given by Conlon, Fox and Zhao with Henriot's estimates of the enveloping sieve weights.Comment: 11 page

Assessing unidimensionality: A comparison of Rasch Modeling, Parallel Analysis, and TETRAD

The evaluation of assessment dimensionality is a necessary stage in the gathering of evidence to support the validity of interpretations based on a total score, particularly when assessment development and analysis are conducted within an item response theory (IRT) framework. In this study, we employ polytomous item responses to compare two methods that have received increased attention in recent years (Rasch model and Parallel analysis) with a method for evaluating assessment structure that is less well-known in the educational measurement community (TETRAD). The three methods were all found to be reasonably effective. Parallel Analysis successfully identified the correct number of factors and while the Rasch approach did not show the item misfit that would indicate deviation from clear unidimensionality, the pattern of residuals did seem to indicate the presence of correlated, yet distinct, factors. TETRAD successfully confirmed one dimension in the single-construct data set and was able to confirm two dimensions in the combined data set, yet excluded one item from each cluster, for no obvious reasons. The outcomes of all three approaches substantiate the conviction that the assessment of dimensionality requires a good deal of judgment. Accessed 19,548 times on https://pareonline.net from October 08, 2007 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right

Corporate Governance and Responsible Bankers: Lesson Learned from Lehman Brothers' Minibonds Saga

The focus of this research is the case of Lehman Brothers’ Minibonds Saga in Hong Kong which directly followed the current economic crisis. Such a study is important to identify the problems faced by Hong Kong since the collapse of Lehman Brothers in US and to reflect on the lessons learned from the case. The research then seeks to identify the enablers in respect of responsibilities from economic, legal, ethical, social and management/administration perspectives contributed to the Minibonds case, by which explore the important role corporate social responsibility plays in the financial market. The research approach adopted in this dissertation includes empirical interviews and secondary data analysis. The findings from this research provide evidence that there is inherent market inefficiency in the banking sector. The main conclusions drawn from this study suggest the important role corporate social responsibility plays in the financial market in Hong Kong and highlight that effective corporate governance system should be embedded with corporate social responsibilities so as to bridge the existing information gap and restore the current trust crisis achieve market efficiency within the banking sector of Hong Kong. This dissertation recommends that ethical and responsible behavior in management practices is essential to restore trust and achieve market efficiency in the financial market