Does enjoying friendship help or impede academic achievement? Academic and social intrinsic value profiles predict academic achievement

We examine the intrinsic value students placed on schoolwork (i.e. academic intrinsic value) and social relationships (i.e. social intrinsic value). We then look at how these values predict middle and high school achievement. To do this, we came up with four profiles based on cluster analyses of 6,562 South Korean middle school students. The four are made up of students who are (1) high in both academic and social intrinsic values (Both-High), (2) high in academic and low in social intrinsic value (Academic), (3) low in academic and high in social intrinsic value (Social) and (4) low in both academic and social intrinsic values (Both-Low). For middle schoolers, the highest academic achievement scores belong to students fitting the Academic profile. For high schoolers, however, such scores belong to two profile groups – the Academic and Both-High profiles. The findings suggest that one component fundamentally important to academic achievement is academic intrinsic value.     

Development and Validation of Measures of Secondary Science Teachers’ PCK for Teaching Photosynthesis

This paper describes procedures by which two types of measures of Pedagogical Content Knowledge (PCK) were developed and validated: (a) PCK Survey and (b) PCK Rubric. Given the topic-specificity of PCK, the measures centered on photosynthesis as taught in high school classrooms. The measures were conceptually grounded in the pentagon model of PCK and designed to measure indispensable PCK that can be applied to any teacher, in any teaching context, for the given topic. Because of the exploratory nature of the study, the measures focus on two key components of PCK: (a) knowledge of students’ understanding in science and (b) knowledge of instructional strategies and representations. Both measures have established acceptable levels of reliability as determined by internal consistency and inter-rater agreement. Evidence related to content validity was gathered through expert consultations, while evidence related to construct validity was collected through analysis of think-aloud interviews and factor analyses. Issues and challenges emerging from the course of the measure development, administration, and validation are discussed with strategies for confronting them. Directions for future research are proposed in three areas: (a) relationships between PCK and teaching experiences, (b) differences in PCK between science teachers and scientists, and (c) relationships between PCK and student learning.     

Effects of collaborative activities on group identity in virtual world

The purpose of this study was to analyze the effects of collaborative activities on group identity in a virtual world such as Second Life. To achieve this purpose, this study adopted events that promoted participants' interactions using tools inherent in Second Life. The interactive tools given to the control group in this study included ‘permissions to move, copy, edit’, ‘give item’, ‘chat’, and ‘send instant message’. In addition to these tools, special tools of ‘give item for praise’ and ‘pollster’ were given to the experimental group. The two groups were compared using scores of group identity, which has nine subcategories. The experimental group showed higher scores in five subcategories than the control group. Thus, we concluded that the use of tools for facilitating participants' interactions is effective for the formation of group identity.     

Unsupervised word sense disambiguation for Korean through the acyclic weighted digraph using corpus and dictionary

Word sense disambiguation (WSD) is meant to assign the most appropriate sense to a polysemous word according to its context. We present a method for automatic WSD using only two resources: a raw text corpus and a machine-readable dictionary (MRD). The system learns the similarity matrix between word pairs from the unlabeled corpus, and it uses the vector representations of sense definitions from MRD, which are derived based on the similarity matrix. In order to disambiguate all occurrences of polysemous words in a sentence, the system separately constructs the acyclic weighted digraph (AWD) for every occurrence of polysemous words in a sentence. The AWD is structured based on consideration of the senses of context words which occur with a target word in a sentence. After building the AWD per each polysemous word, we can search the optimal path of the AWD using the Viterbi algorithm. We assign the most appropriate sense to the target word in sentences with the sense on the optimal path in the AWD. By experiments, our system shows 76.4% accuracy for the semantically ambiguous Korean words.     

International trends in health science librarianship part 11: Japan and Korea

This is the 11th in a series of articles exploring international trends in health science librarianship. The previous article in this series looked at the Far East (Greater China, Hong Kong and Taiwan). The current issue surveys developments in Japan and Korea. The next issue will explore trends in South Asia (India, Pakistan, Bangladesh and Sri Lanka). Next year all four issues will be devoted to trends in four regions in Africa (Southern Africa, East Africa, West Africa and North Africa. JM     

Bubble-free and pulse-free fluid delivery into microfluidic devices

The bubble-free and pulse-free fluid delivery is critical to reliable operation of microfluidic devices. In this study, we propose a new method for stable bubble-free and pulse-free fluid delivery in a microfluidic device. Gas bubbles are separated from liquid by using the density difference between liquid and gas in a closed cavity. The pulsatile flow caused by a peristaltic pump is stabilized via gas compressibility. To demonstrate the proposed method, a fluidic chamber which is composed of two needles for inlet and outlet, one needle for a pinch valve and a closed cavity is carefully designed. By manipulating the opening or closing of the pinch valve, fluids fill up the fluidic chamber or are delivered into a microfluidic device through the fluidic chamber in a bubble-free and pulse-free manner. The performance of the proposed method in bubble-free and pulse-free fluid delivery is quantitatively evaluated. The proposed method is then applied to monitor the temporal variations of fluidic flows of rat blood circulating within a complex fluidic network including a rat, a pinch valve, a reservoir, a peristaltic pump, and the microfluidic device. In addition, the deformability of red blood cells and platelet aggregation are quantitatively evaluated from the information on the temporal variations of blood flows in the microfluidic device. These experimental demonstrations confirm that the proposed method is a promising tool for stable, bubble-free, and pulse-free supply of fluids, including whole blood, into a microfluidic device. Furthermore, the proposed method will be used to quantify the biophysical properties of blood circulating within an extracorporeal bypass loop of animal models.     

Motivational beliefs and cognitive processes in mathematics achievement, analyzed in the context of cultural differences: a Korean elementary school example

The relations among students’ motivational beliefs, cognitive processes, and academic achievement were investigated. A 51-item questionnaire together with a mathematics achievement test was administered to 459 fifth graders in Korean elementary school mathematics classrooms. Results indicated that, in general, students’ cognitive processes related closely to competence beliefs, task values, and achievement goals, and more importantly their success or failure in mathematics achievement was closely linked to competence beliefs, performance-avoidance goals, and persistence strategies. Positive evidence of performance-approach goals was observed in math learning relative to task goals. As expected, performance-avoidance goals turned out to be detrimental to students’ math learning. These findings are generally congruent with the motivational theories and support the position that students should be encouraged to adopt task goals and actively involve themselves in math class activities. However, it also behooves us to recognize the potential benefits of performance-approach goals in different cultural contexts, such as the Korean elementary school math classrooms.     

Refillable and magnetically actuated drug delivery system using pear-shaped viscoelastic membrane

We report a refillable and valveless drug delivery device actuated by an external magnetic field for on-demand drug release to treat localized diseases. The device features a pear-shaped viscoelastic magnetic membrane inducing asymmetrical deflection and consecutive touchdown motion to the bottom of the dome-shaped drug reservoir in response to a magnetic field, thus achieving controlled discharge of the drug. Maximum drug release with 18 ± 1.5 μg per actuation was achieved under a 500 mT magnetic flux density, and various controlled drug doses were investigated with the combination of the number of accumulated actuations and the strength of the magnetic field.     

Flight dynamics of the screw kick in rugby

This paper describes the aerodynamic forces and the flight trajectory for the screw (spiral) kick in rugby. The screw kick is defined as that which causes the ball to spin on its longitudinal axis. The aerodynamic forces acting on a rugby ball spinning on its longitudinal axis were measured in a wind tunnel using a six-component strut type balance. It was found that the drag, the lift and the pitching moment depend on the angle of attack, while the side force (Magnus force) depends on both the spin rate and the angle of attack in the range where the wind speed lies between 15 and 30 m s^-1 and the spin rate is between 1 and 10 revolutions per second. Moreover, the flight trajectory was obtained by integrating the full nonlinear six degrees of freedom equations of motion on the basis of aerodynamic data. In a simulation, a ball spinning on its longitudinal axis tended to hook toward or away from the touchline even if the velocity and angular velocity vectors were parallel to the touchline. The direction of the hook depends on the direction of the angular velocity vector. The initial direction of the hook depends on the relationship between the flight path angle and the pitch angle as well as the direction of the angular velocity vector.