Development of a void ratio-moisture ratio-net stress framework for the prediction of the volumetric behavior of unsaturated granular materials

Despite extensive research on the behavior of unsaturated fine-grained materials, there is still a lack of understanding of the volumetric behavior of unsaturated granular materials. In this research, a model has been developed to predict the fundamental volumetric behavior of unsaturated granular materials through loading and wetting state paths. In this regard, a loading-wetting surface was developed in a space of void ratio-moisture ratio-net stress. A distinctive feature of the proposed model is the relative simplicity in obtaining the model parameters using conventional geotechnical testing equipment. Two types of recycled granular materials, commonly applied in unbound pavements were used, namely, recycled crushed brick (CB) and excavation waste rock (WR). The uniqueness of the developed surface was evaluated by employing a number of loading and wetting state paths. The results indicate that the developed surface is unique in its loading state paths; however, it only shows uniqueness in its wetting state paths for stress levels greater than 2000 kPa. The proposed model seeks to introduce the application of the unsaturated soil mechanics theory, for predicting the behavior of granular materials in the field, by providing a practical and cost-effective methodology.     

Development and validation of New Media Literacy Scale (NMLS) for university students

Along with the emergence of new media technologies, individuals are now expected not only to consume but also produce, share and criticize digital contents. Being new media literate, they also need to know socio-cultural and emotional aspects of new media beyond its technical characteristics. New media literacy (NML) involves a series of crucial skills needed for living and working in the mediated and participatory society of 21st century. Although there has been a growing interest in the conceptualization of NML, the literature lacks a measuring instrument to operationalize NML. This study attempts to fill this gap by developing and validating a NML scale (NMLS) for university students. The sample included 1226 students at a state university in Turkey. Both exploratory and confirmatory factor analyses as well as item analyses including internal consistency coefficients, item-total correlations, and item discrimination powers were conducted to determine construct validity and reliability. Consistent with the adopted theoretical framework, the 35-item NMLS comprised four factors: Functional Consumption, Critical Consumption, Functional Prosumption, and Critical Prosumption. Potential applications of NMLS for measuring students’ new media competencies were discussed within the pedagogical and research contexts.     

Enhancing Virtual Reference: Techniques and Technologies to Engage Users and Enrich Interaction

Virtual reference service has become ubiquitous in academic libraries. The increased adoption of chat technology brings to light some of the challenges of providing high-quality reference service. The lack of a personal connection, increased transaction time, and technical problems are often cited. Techniques, such as conducting a reference interview or using online communication conventions, can make virtual reference as effective as face-to-face reference. Additionally, inclusion of video or Web annotation in the virtual reference session can add an element of personalization that might otherwise be missing. Virtual reference can be an emotionally rich, engaging, and effective form of reference service if these techniques and technologies are adopted.     

The Information Literacy Challenge

Abstract

Technological changes are occurring rapidly. As one result, students entering college are bringing very disparate computer skills and attitudes. Some students are reluctant to embrace new technologies; others demand electronic resources for all assignments. By considering the computer access and Internet resources available to elementary school students today, we can only imagine what our users of tomorrow will expect from libraries. Although college students may arrive at our libraries with increased computer skills, their knowledge of electronic information may be lacking. Definitions of information literacy and an overview of information literacy skills are outlined. The Digital Information Literacy program at The University of Texas at Austin, as well as the technological environment and facilities at the institution, serve as a case study for integrating information literacy skills into traditional services and partnerships.     

Enhanced photocatalytic degradation performance of organic contaminants by heterojunction photocatalyst BiVO4/TiO2/RGO and its compatibility on four different tetracycline antibiotics

Photocatalytic performance of four tetracycline antibiotics using BiVO₄/TiO₂/RGO composites was investigated. To make full use of catalysis, optimum preparation conditions involved RGO content, solution pH and hydrothermal temperature on the structure forming of BiVO₄/TiO₂/RGO composites were investigated. Subsequently, the obtained visible light-driven photocatalyst was used to degrade four kinds of tetracycline antibiotics involved tetracycline (TC), chlortetracycline (CTC), oxytetracycline (OTC) and doxycycline (DXC) for wastewater treatment. Results showed that BiVO₄/TiO₂/RGO photocatalyst exhibited excellent photocatalytic activity and high compatibility due to the enhanced separation efficiency of photo-generated carriers with high reduction and oxidation capability. The degradation process of four kinds of tetracycline antibiotics was traced and detected through identifying intermediates produced in the reaction system. And a possible catalytic mechanism for BiVO₄/TiO₂/RGO photocatalyst was put forward based on band gap structure of BiVO₄ and TiO₂.     

What makes you a digital native? Is it enough to be born after 1980?

The purpose of this study is to determine levels of technological proficiency among university students to see if they should be characterized as “digital natives.” For this purpose, rather than using types and frequency of technology use to characterize a digital native, the Digital Native Assessment Scale (DNAS) developed by Teo (2013) was employed. This scale has an established reliability and validity measure. It measures several factors (e.g., grew up with technology, comfortable with multi-tasking, reliant on graphics for communication, thrive on instant gratifications and rewards, etc.) relating to accepted characteristics of a digital native. The participants in the study were 560 university students, 278 of whom were from Turkey and 282 from Kyrgyzstan. The findings indicate that these university students actively used computers and the Internet. The statistical results show that digital natives can be characterized by including their academic year (Freshman, Sophomore, etc.), national culture, and experiences with technology (computers, tablet PCs, and the Internet). The results also indicate that there are no significant differences in the participants' perceptions of themselves as digital natives due to their gender or academic disciplines.     

The Dirty Details of Gopher Maintenance

Abstract

This paper describes the details of maintaining an Internet information service, focusing on the experience of Documents Center staff in the University of Michigan Library with the “Department of Commerce Economic Data (UMich)” gopher area. Described are the evolution of the service, the logistics of obtaining and posting the files, developing staff skills and knowledge, file selection, and provision of enhanced access and assistance. Long term considerations are discussed. Internet information services differ from more traditional library services and materials maintenance because they require special skills, equipment, and constant reassessment. Despite this, the benefits of providing such services are significant for the academic library's clientele, its staff, and the Internet community overall.     

Temperature stable 0.35Ag2MoO4-0.65Ag0.5Bi0.5MoO4 microwave dielectric ceramics with ultra-low sintering temperatures

In this study, the novel temperature-stable (1-x)Ag₂MoO₄-xAg_0.5Bi_0.5MoO₄ microwave dielectric ceramics were prepared by a modified solid-state reaction method. The phase composition, microstructures and microwave dielectric properties of the (1-x)Ag₂MoO₄-xAg_0.5Bi_0.5MoO₄ ceramics were investigated. All the compounds can be sintered well at ultra-low temperatures (<540 °C). The XRD and SEM analysis indicate that the Ag₂MoO₄ and the Ag_0.5Bi_0.5MoO₄ can coexist with each other. When x = 0.65, the ceramics exhibit the best microwave dielectric properties with a relative permittivity of 23.9, a Q × f value of 16,200 GHz (at 7.3 GHz) and a near-zero TCF value of -2.4 ppm/°C at 520 °C. The results indicate that temperature-stable (1-x)Ag₂MoO₄-xAg_0.5Bi_0.5MoO₄ ceramics are promising candidates for low temperature co-fired ceramics (LTCC) applications.