Using cluster validation criterion to identify optimal feature subset and cluster number for document clustering

This paper presents a cluster validation based document clustering algorithm, which is capable of identifying an important feature subset and the intrinsic value of model order (cluster number). The important feature subset is selected by optimizing a cluster validity criterion subject to some constraint. For achieving model order identification capability, this feature selection procedure is conducted for each possible value of cluster number. The feature subset and the cluster number which maximize the cluster validity criterion are chosen as our answer. We have evaluated our algorithm using several datasets from the 20Newsgroup corpus. Experimental results show that our algorithm can find the important feature subset, estimate the cluster number and achieve higher micro-averaged precision than previous document clustering algorithms which require the value of cluster number to be provided.     

Social constructivism, projective identity, and learning: case study of nathan

In this paper we consider the significant issue of identity and how it relates to learning. Importantly, we narrow down the study in terms of how projective identity interplays with learning from the point of view of the learner and his/her social community. Self and community cannot be divorced. In order to illustrate this concept, we describe a case study involving an 11 years old boy in a learning context commonly referred to as an informal learning environment. This environment would include the community in which projective identity evolves. The trajectory of identity projection can be conceived in Ricoeurian terms of a plot where actors perform actions in role playing situations. This plot metaphor is consistent to the many interactions within MMPOGs and fictional worlds currently in existence. We conceive of an identity projection framework as our contributions to knowledge.     

Engaging Students with Art-Based S-R-C (Sense of Belonging,Resistance, and Coalition Building) Strategies for Anti-Racism

In this article, we discuss our struggles and efforts to respond to Asian American and Pacific Islander (AAPI) hate crimes and anti-Asian racism, as well as explore ways to address the issues of anti-Asian racism, violence, myths, and stereotypes in the art classroom. We researched and learned from contemporary Asian American artists, attended anti-racism virtual talks, and examined various anti-racism pedagogical approaches. As an outcome of our research to confront anti-racism, we developed S-R-C strategies to engage students with art-based anti-racism, which include facilitating a sense of belonging (S), resisting anti-Asian racism (R), and coalescing with other minority groups and allies (C). These strategies were developed to fully embrace the equity, diversity, and inclusivity of AAPI sequentially and holistically. This article also reports how we use the S-R-C strategies to guide our pre-service art teachers to confront anti-Asian racism and advocate for anti-racism teaching practices.     

Teachers’ and Children’s Differing Views on Relationships and Their Associations with Academic Outcomes

Early Childhood Education Journal - Preschool children’s relationships with their teachers play an important role in their learning and development. Despite this importance, extant research...     

College students’ motivation and learning strategies profiles and academic achievement: a self-determination theory approach

The development of effective self-regulated learning strategies is of interest to educationalists. In this paper, we examine inherent individual difference in self-regulated learning based on Motivated Learning for Learning Questionnaire (MLSQ) using the cluster analytic approach and examine cluster difference in terms of self-determination theory related variables. The sample of the study consisted of 238 junior college students from 12 intact classes. Two adaptive clusters and two maladaptive clusters were uncovered based on the MLSQ, with the adaptive clusters showing better academic grades. Results from the one-way MANOVA showed that the four clusters differed significantly in terms of their needs satisfaction, behavioural regulations, enjoyment, effort and value. The findings supported the importance of needs satisfaction in the development of self-regulated learning behaviour.     

Relative position keeping in satellite formation flying with input saturation

This paper studies a relative position keeping problem in satellite formation flying with input saturation. The relative motion dynamics is designed with polytopic-type uncertainties by considering elliptic and noncoplanar formation, and unknown angular rate and acceleration within some boundary. A composite nonlinear feedback control law is developed by using a low-and-high gain control scheme with an algebraic Riccati inequality (ARI). In the presence of input saturation and disturbances, finite-gain _L∞$L_{\infty }$ stability of the relative motion dynamics is ensured using the proposed control law. Additionally, the domain of attraction for the stability is evaluated by formulating an optimization problem. Through numerical simulations, the validity of the proposed scheme is illustrated.     

昼夜浮影

日光拨开黑夜的长发,夜影裹起白昼的身躯。光与影欢乐又悲伤,无自觉地浮起、飘落,都是纷纷的美丽。黑夜敛起了忧郁的目光,白昼舞落了欢愉的长袖。光与影不相为伴,所见的,都是炫目的纯净。     

The effect of caffeine ingestion on human neutrophil oxidative burst responses following time-trial cycling

Abstract

Following fixed-duration exercise of submaximal intensity, caffeine ingestion is associated with an attenuation of the exercise-induced decline in N-formyl-methionyl-phenyl-alanine (f-MLP) stimulated neutrophil oxidative burst. However, the response following high-intensity exhaustive exercise is unknown. Nine endurance-trained male cyclists ingested 6 mg caffeine or placebo per kilogram of body mass 60 min before cycling for 90 min at 70% of maximal oxygen consumption ([Vdot]O_2max) and then performing a time-trial requiring an energy expenditure equivalent to 30 min cycling at 70% maximum power output. Time-trial performance was 4% faster in the caffeine than in the placebo trial (P = 0.043). Caffeine was associated with an increased plasma adrenaline concentration after 90 min of exercise (P = 0.046) and immediately after the time-trial (P = 0.02). Caffeine was also associated with an increased serum caffeine concentration (P < 0.01) after 90 min of exercise and immediately after the time-trial, as well as 1 h after the time-trial. However, the f-MLP-stimulated neutrophil oxidative burst response fell after exercise in both trials (P = 0.002). There was no effect of caffeine on circulating leukocyte or neutrophil counts, but the lymphocyte count was significantly lower on caffeine (20%) after the time-trial (P = 0.003). Our results suggest that high-intensity exhaustive exercise negates the attenuation of the exercise-induced decrease in neutrophil oxidative burst responses previously observed when caffeine is ingested before exercise of fixed duration and intensity. This may be associated with the greater increase in adrenaline concentration observed in the present study.     

The Diffusion and Transmission of Cricket among European,Indigenous and Migrant Communities in the British Straits Settlements and Malay States during the Late Eighteenth and Nineteenth Century, 1786–1899

The British colonised Penang in 1786, Malacca in 1895 and Singapore in 1819. In 1874, the British, through its Residents, came to control the Governments of Perak, Selangor and Sungei Ujong, and wherever they went, they indulged in their leisure pursuits such as horse riding and cricket. This research attempts to show how the immigrant Malay Eurasian, Chinese and Tamil communities come into contact with the different British and European communities and were introduced to cricket. The process of diffusion and acceptance becomes evident when the local populations in turn set up their own sports clubs and cricket clubs. The study tries to identify the various means of the cultural transmission of sports by the different ethnic groups during British colonial rule from 1876 to 1899.     

Two sides of the same coin: video annotations and in-video questions for active learning

Educational technology research and development - Video in education has become pervasive. Globally, educators are recording instructional videos to augment their students’ learning and, in...