Evaluating a range of learning schedules: hybrid training schedules may be as good as or better than distributed practice for some tasks

We investigated theoretically and empirically a range of training schedules on tasks with three knowledge types: declarative, procedural, and perceptual-motor. We predicted performance for 6435 potential eight-block training schedules with ACT-R's declarative memory equations. Hybrid training schedules (schedules consisting of distributed and massed practice) were predicted to produce better performance than purely distributed or massed training schedules. The results of an empirical study (N = 40) testing four exemplar schedules indicated a more complex picture. There were no statistical differences among the groups in the declarative and procedural tasks. We also found that participants in the hybrid practice groups produced reliably better performance than ones in the distributed practice group for the perceptual-motor task – the results indicate training schedules with some spacing and some intensiveness may lead to better performance, particularly for perceptual-motor tasks, and that tasks with mixed types of knowledge might be better taught with a hybrid schedule.     

Miniaturized Battery‐Free Wireless Systems for Wearable Pulse Oximetry

Development of unconventional technologies for wireless collection and analysis of quantitative, clinically relevant information on physiological status is of growing interest. Soft, biocompatible systems are widely regarded as important because they facilitate mounting on external (e.g., skin) and internal (e.g., heart and brain) surfaces of the body. Ultraminiaturized, lightweight, and battery‐free devices have the potential to establish complementary options in biointegration, where chronic interfaces (i.e., months) are possible on hard surfaces such as the fingernails and the teeth, with negligible risk for irritation or discomfort. Here, the authors report materials and device concepts for flexible platforms that incorporate advanced optoelectronic functionality for applications in wireless capture and transmission of photoplethysmograms, including quantitative information on blood oxygenation, heart rate, and heart rate variability. Specifically, reflectance pulse oximetry in conjunction with near‐field communication capabilities enables operation in thin, miniaturized flexible devices. Studies of the material aspects associated with the body interface, together with investigations of the radio frequency characteristics, the optoelectronic data acquisition approaches, and the analysis methods capture all of the relevant engineering considerations. Demonstrations of operation on various locations of the body and quantitative comparisons to clinical gold standards establish the versatility and the measurement accuracy of these systems, respectively.     

Binder removal and microstructure with burnout conditions in BaTiO3 based Ni-MLCCs

The burnout conditions in multilayer ceramic capacitors (MLCCs) have been investigated to optimize the binder removal condition and to control the microstructure during the burnout process. MLCCs showed a delamination for the heating rate of 7 °C/min at 200 °C, and 6 °C/min at 250 °C and 300 °C in the ambient atmosphere. The heating rate affected the pore size distribution and mean pore size, showing the smaller and larger mean pore size in the reducing and at higher temperature, respectively. The cumulative pore surface area was dependent on the burnout temperature rather than the heating rate. The minimum pore surface area could be obtained at 300 °C with the heating rate of 3 °C/min, in which the pores were connected to be an open structure. The atmosphere and temperature affected the burnout microstructure related to the binder removal without the effect of the heating rate.     

Dispersant-Ethyl Cellulose Binder Interactions at the Ni Particle-Dihydroterpineol Interface

The interaction of a dispersant and a binder at the Ni particle surface is investigated to identify their influence on the dispersion stability of Ni particles in dihydroterpineol (DHT). Six different commercial dispersants are used to obtain a highly dispersed Ni suspension, and ethyl cellulose (EC) is used as a binder for the preparation of a Ni paste. The effectiveness of the dispersants on the dispersion stability of the Ni particles in DHT is evaluated by measuring the rheological behavior of the Ni suspension. Hypermer KD3 and RE610, among six different commercial dispersants, are found to be an effective dispersant for the Ni particles in DHT without EC. However, upon the addition of EC, different rheological behaviors of the Ni suspensions are shown according to the added dispersants. EC does not affect the rheological behavior of the RE610-stabilized Ni suspension. On the other hand, the addition of EC increases the apparent and relative viscosities of the Hypermer KD3-stabilized Ni suspension and causes a transition in rheological behavior from shear thinning behavior to shear thickening behavior. The adsorption results reveal that the deterioration in the stability of the Hypermer KD3-stabilized Ni suspension with the addition of EC is due to the partial displacement of the preadsorbed Hypermer KD3 by the EC. The influence of the interactions between the dispersant and binder on the dispersion stability of the Ni pastes is also confirmed via observations of the variations in the agglomerated particle size with the addition of EC.     

Enhancement of electro‐optical properties in holographic polymer‐dispersed liquid crystal films by incorporation of multiwalled carbon nanotubes into a polyurethane acrylate matrix

Holographic polymer‐dispersed liquid crystal (HPDLC) films were fabricated with varying amounts of multiwalled carbon nanotubes (MWCNTs) to optimize the electro‐optical performance of the HPDLC films. The MWCNTs were well dispersed in the prepolymer mixture up to 0.5 wt%, implying that polyurethane acrylate (PUA) oligomer chains wrap the MWCNTs along their length, resulting in high diffraction efficiency and good phase separation. The hardness and elastic modulus of the polymer matrix were enhanced with increasing amounts of MWCNTs because of the reinforcement effect of the MWCNTs with intrinsically good mechanical properties. The increased elasticity of the PUA matrix and the immiscibility between the matrix and the liquid crystals (LCs) gradually increased the diffraction efficiency of the HPDLC films. However, the diffraction efficiency of HPDLC films with more than 0.05 wt% MWCNTs was reduced, caused by poor phase separation between the matrix and LCs because of the high viscosity of the reactive mixture. HPDLC films showing a low driving voltage (<3 V µm^?1), a fast response time (<10 ms) and a high diffraction efficiency (>75%) could be obtained with 0.05 wt% MWCNTs at 40 wt% LCs. Copyright © 2010 Society of Chemical Industry     

Inula britannica fermented with probiotic Weissella cibaria D30 exhibited anti-inflammatory effect and increased viability in RAW 264.7 cells

Food Science and Biotechnology - The objective of this study was to increase the bioavailability of Inula britannica (IB) through fermentation with probiotic Weissella cibaria D30, and to evaluate...     

The antecedents and consequences of technology standardizations in Korean IT small and medium-sized enterprises

With rapid changes in the business environment, leading or utilizing technology standards may help firms gain better performance through competitive advantage. Such activities related to technology standards are likely to provide numerous opportunities or benefits to small and medium-sized enterprises (SMEs) in the highly technological divide among firms. However, few studies have paid attention to drivers, obstacles, and results of technology standards activities in SMEs. Consequently, this study bridges this research gap by identifying the factors influencing technology standardizations, which in turn contribute to firm performance in SMEs. The analytic results of survey data collected from 250 SMEs in the Korean IT sector reveal that all technology standardizations have an effect firm performance. Benefits from standards, R&D capability, and insufficient resources are influential factors of all technology standardizations. However, support of related institutes only affects inbound standardization. This study discusses theoretical and practical implications on technology standardizations in SMEs based on these findings.