Teaching time telling and examining the relative effects of rate-building and rate-controlled practice on the retention and generalization of the time cues

The present study aimed at replicating some of the procedures used in the existing empirical research on teaching time telling in a population which has not previously been used, i.e., adults with mild intellectual disabilities. The first part aimed to train three adults with mild intellectual disability and with minimal skills to tell the time to the nearest 5 min interval. The target skill was trained in 12 phases and each phase consisted of acquisition training, discrimination training and review training. A multiple-probe design was used over phases. The results showed that the procedures used in the training were effective in establishing time telling with these intellectually disabled adults. The training had brought about 55 to 67 percent improvements in the time telling skills of all three participants and the target behaviour was acquired by all the participants in 48 to 65 days, with at least 30 min of training each day. The common discrimination errors encountered, the general effectiveness of the training program, the application and the social relevance of the trained skill are discussed. The second part of this study aimed at comparing the relative effects of “fast practice”, “slow practice” and “no practice” on the retention and generalization of the time telling skills, when amount of practice and reinforcement was controlled across conditions. An Alternating Treatments, repeated measure, within-subjects design was used. The results indicated that, while periods without practicing led to the deterioration in the accuracy of skill, retention or generalization of the skill was not enhanced by rate-building to a fluency performance standard over the same amount of rate-controlled practice. Limitations of the study to provide firm conclusions are discussed

Security Toolbox for Detecting Novel and Sophisticated Android Malware

This paper presents a demo of our Security Toolbox to detect novel malware in Android apps. This Toolbox is developed through our recent research project funded by the DARPA Automated Program Analysis for Cybersecurity (APAC) project. The adversarial challenge ("Red") teams in the DARPA APAC program are tasked with designing sophisticated malware to test the bounds of malware detection technology being developed by the research and development ("Blue") teams. Our research group, a Blue team in the DARPA APAC program, proposed a "human-in-the-loop program analysis" approach to detect malware given the source or Java bytecode for an Android app. Our malware detection apparatus consists of two components: a general-purpose program analysis platform called Atlas, and a Security Toolbox built on the Atlas platform. This paper describes the major design goals, the Toolbox components to achieve the goals, and the workflow for auditing Android apps. The accompanying video (http://youtu.be/WhcoAX3HiNU) illustrates features of the Toolbox through a live audit.Comment: 4 pages, 1 listing, 2 figure

Direct microscopic evidence of shear induced graphitization of ultrananocrystalline diamond films

The origin of ultralow friction and high wear resistance in ultrananocrystalline diamond (UNCD) films is still under active debate because of the perplexed tribochemistry at the sliding interface. Herein, we report a comparative study on surface topography and nanoscale friction of tribofilms, in wear tracks of two sets of UNCD films having different structural characteristics. Despite both the films display ultralow coefficient of friction, the UNCD films grown under Ar atmosphere (UNCDAr) exhibit a high wear resistance while the wear rate is higher for the films grown in N2 (UNCDN). Frictional force microscopic (FFM) investigations clearly reveal the manifestation of shear induced graphitization on both the films. However, the wear track of UNCDAr films have a large network of a few layer graphene (FLG) structures over the amorphous carbon tribofilms while only isolated clusters of FLG structures are present in the wear track of UNCDN films. Here, we demonstrate the direct micro-/nanoscopic evidence for the formation of large network of ~ 0.8 - 6 nm thick FLG structures, as a consequence of shear induced graphitization and discuss their decisive role in ultralow friction and wear.Comment: 33 pages, 8 figures, 1 Tabl

Electrical transport in magnesium aluminate

The conductivity of MgAl2O4 has been measured at 1273, 1473 and 1673 K as a function of the partial pressure of oxygen ranging from 105 to 10−14 Pa. The MgAl2O4 pellet, sandwiched between two platinum electrodes, was equilibrated with a flowing stream of either Ar + O2, CO + CO2 or Ar + H2 + H2O mixture of known composition. The gas mixture established a known oxygen partial pressure. All measurements were made at a frequency of 1 kHz. These measurements indicate pressure independent ionic conductivity in the range 1 to 10−14 Pa at 1273 K, 10−1 to 10−12 Pa at 1473 K and 10−1 to 10−4 Pa at 1673 K. The activation energy for ionic conduction is 1·48 eV, close to that for self-diffusion of Mg2+ ion in MgAl2O4 calculated from the theoretical relation of Glyde. Using the model, the energy for cation vacancy formation and activation energy for migration are estimated

Transfer of Vertical Graphene Nanosheets onto Flexible Substrates towards Supercapacitor Application

Vertical graphene nanosheets (VGNs) are the material of choice for next-generation electronic device applications. The growing demand for flexible devices in electronic industry brings in restriction on growth temperature of the material of interest. However, VGNs with better structural quality is usually achieved at high growth temperatures. The difficulty associated with the direct growth on flexible substrates can overcome by adopting an effective strategy of transferring the well grown VGNs onto arbitrary flexible substrates through soft chemistry route. Hence, we demonstrated a simple, inexpensive and scalable technique for the transfer of VGNs onto arbitrary substrates without disrupting its morphology and structural properties. After transfer, the morphology, chemical structure and electronic properties are analyzed by scanning electron microscopy, Raman spectroscopy and four probe resistive methods, respectively. Associated characterization investigation indicates the retention of morphological, structural and electrical properties of transferred VGNs compared to as-grown one. Furthermore the storage capacity of the VGNs transferred onto flexible substrates is also examined. A very lower sheet resistance of 0.67 kOhm/sq. and excellent supercapacitance of 158 micro-Farrad/cm2 with 91.4% retention after 2000 cycles confirms the great prospective of this damage-free transfer approach of VGNs for flexible nanoelectronic device application

A Decade of Supply Chain Management Literature: Past, Present and Future Implications

This study covers a decade of academic research in the Supply Chain Management (SCM) field, offering an in-depth analytical review focused on the existing trends and gaps in the supply chain literature. Nine academic journals were investigated and a subject categorization is developed for SCM research. A content analysis was then conducted on 405 articles, focusing on the categories covered within the SCM literature, various levels of the chain examined and sample populations and industries studied, as well as the research methods employed. Finally, a conceptual framework of the most highly researched categories in SCM indicates that there is a need for more research that seeks to understand the nature of multiple links in SCM chains and networks, as opposed to focusing on dyadic and inter-firm relationships