The Perceived Attributes of Wi-Fi Technology and the Diffusion Gap among University Faculty Members: A Case Study

The purpose of this case study is to investigate and understand the perceived attributes of Wi-Fi technology and the diffusion gap among university faculty members. Rogers’ diffusion theory provides the theoretical framework to guide the qualitative study. Semi-structured interviews were used to collect data. The participants were 16 faculty members (nine adopters and seven non-adopters) from six colleges at a midwestern state university. Findings from this study show the differences between early adopters and non-adopters (the mainstream) in these aspects: knowledge and skill of technology, teaching practices, teaching philosophy, and technology needs. These different perceptions toward Wi-Fi technology lead to diffusion “gap” between early adopters and the mainstream. This diffusion gap implies that a different support infrastructure is needed for mainstream faculty to integrate technology for teaching and learning. An institution needs to act as a change agent to promote further technology adoption by the mainstream faculty

Vegetation restoration in Northern China: A contrasted picture

China started a long- term effort to mitigate desertification and ensure the sustainability of its environment by implementing multiple large- scale national ecological restoration projects since 1978, but their success has been highly debated for a long time. Here, we estimated the change of vegetation fraction cover (VFC) in the Three- North Shelterbelt Programme (TNSP) region over the past three decades on the basis of the Normalized Difference Vegetation Index dataset from the Global Inventory Monitoring and Modeling System. We evaluate the national strategy of vegetation restoration in North China by comparing rainfall patterns, vegetation change, and national ecological restoration programs on the basis of the Global Meteorological Forcing Dataset and the China Forestry Statistical Yearbooks. We find that the western, central, and eastern parts of the TNSP region exhibited a distinct increase in vegetation coverage. The western region had the highest increase of annual precipitation, but this did not result in the highest VFC increase. We infer that ecological restoration activities are the factor leading to the observed increase in VFC in the eastern and central region compared with the western region. The low survival rate of planted trees in the forest of the TNSP region indicates that it is necessary to improve the mode of vegetation restoration to obtain optimal returns and avoid excessive investment. The success of new strategies, for example, natural restoration and quasinatural afforestation are promising as an alternative method. China’s experiences in reforestation will be very beneficial for other countries to promote land degradation mitigation and vegetation improvement in the arid and semiarid areas.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154888/1/ldr3314_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154888/2/ldr3314.pd

Modelling generalisation and power dissipation of flexible-wheel suspension concept for planetary surface vehicles

Flexible-wheel (FW) suspension concept has been regarded to be one of the novel technologies for future planetary surface vehicles (PSVs). This study develops generalised models for fundamental stiffness and damping properties and power consumption characteristics of the FW suspension with and without considering wheel-hub dimensions. Compliance rolling resistance (CRR) coefficient is also defined and derived for the FW suspension. Based on the generalised models and two dimensionless measures, suspension properties are analysed for two FW suspension configurations. The sensitivity analysis is performed to investigate the effects of the design parameters and operating conditions on the CRR and power consumption characteristic of the FW suspension. The modelling generalisation permits analyses of fundamental properties and power consumption characteristics of different FW suspension designs in a uniform and very convenient manner, which would serve as a theoretical foundation for the design of FW suspensions for future PSVs

Editors' perspectives: road vehicle suspension design, dynamics, and control

This paper provides an overview of the latest advances in road vehicle suspension design, dynamics, and control, together with the authors' perspectives, in the context of vehicle ride, handling, and stability. The general aspects of road vehicle suspension dynamics and design are discussed, followed by descriptions of road-roughness excitations with a particular emphasis on road potholes. Passive suspension system designs and their effects on road vehicle dynamics and stability are presented in terms of in-plane and full-vehicle arrangements. Controlled suspensions are also reviewed and discussed. The paper concludes with some potential research topics, in particular those associated with the development of hybrid and electric vehicles

The Partial Discharge Evolution Characteristics of 10kV XLPE Cable Joint

The evolution of partial discharge (PD) with time can provide a deep understanding on the insulation status of power cables. It is of great significance for intelligent operation and maintenance of power cables. In this paper, the PD pulse signal in the 10kV cable joint during accelerated electrical aging under 20kV AC voltage was acquired in the real-time for about 160h. The characteristic parameters of partial discharge–pulse number, average voltage, maximum voltage and energy per second were extracted. The results show that the phase of partial discharge is mainly concentrated at 30°-90° and 200°-270°, which can be characterized as internal discharge. PD characteristic parameters gradually increased after 50h. The pulse number, energy per second and the average voltage of PD pulse reached a peak between 60-80h. Then these parameters reached a steady state between 80-130h and showed a steep rise after 130h. The maximum voltage of PD pulse shows a steep rise at about 70h from 0.1V to 0.3V. It rises sharply from 0.3V to 0.5V after about 120h and then enters a relatively stable oscillation stage. The evolution rules of the PD characteristic parameters comply well with the electrical tree growth states-initiation period, lag period and rapid growth period. Furthermore, model for predicting and evaluating the insulation state based on BP neural network are established and the prediction accuracy is verified. The proposed models can provide early warning for the cable joint before the insulation failure, so as to ensure timely maintenance or replacement

Hdp Code: A Horizontal-Diagonal Parity Code to Optimize i/o Load Balancing

Abstract-With higher reliability requirements in clusters and data centers, RAID-6 has gained popularity due to its capability to tolerate concurrent failures of any two disks, which has been shown to be of increasing importance in large scale storage systems. Among various implementations of erasure codes in RAID-6, a typical set of codes known as Maximum Distance Separable (MDS) codes aim to offer data protection against disk failures with optimal storage efficiency. However, because of the limitation of horizontal parity or diagonal/anti-diagonal parities used in MDS codes, storage systems based on RAID-6 suffers from unbalanced I/O and thus low performance and reliability. To address this issue, in this paper, we propose a new parity called Horizontal-Diagonal Parity (HDP), which takes advantages of both horizontal and diagonal/anti-diagonal parities. The corresponding MDS code, called HDP code, distributes parity elements uniformly in each disk to balance the I/O workloads. HDP also achieves high reliability via speeding up the recovery under single or double disk failure. Our analysis shows that HDP provides better balanced I/O and higher reliability compared to other popular MDS codes