Surface Hardening of Ti-15V-3Al-3Cr-3Sn Alloy after Cyclic Hydrogenation and Subsequent Solution Treatment

The as-received and preheated (1000°C-30 min. and 500°C-30 min.) sheets of Ti-15V-3Al-3Cr-3Sn alloy (Ti-153) were treated according to the predetermined process including a cyclic electrolytic hydrogenation (at 50 mA/cm2 for 1 hr and at 5 mA/cm2 for 10 hrs) combining a subsequent solution treatment to see the effects of various operating parameters on the evolution of microstructure and the variations of hardness. The hardening effect deriving from solid-solution strengthening of hydrogen eventually overrode that from precipitation hardening. The maximum hardness elevation was from 236.9 to 491.1 VHN

Performance evaluation of an enhanced distributed channel access protocol under heterogeneous traffic

Recently there have been considerable interests focusing on the performance evaluation of IEEE 802.11e Medium Access Control (MAC) protocols, which were proposed for supporting Quality of Services (QoS) in Wireless Local Area Networks (WLANs). Different from most existing work, this study has conducted comprehensive performance evaluation and analysis of the IEEE 802.11e Enhanced Distributed Channel Access (EDCA) protocol in the presence of heterogeneous network traffic including non-bursty Poisson, bursty ON/OFF, and self-similar traffic generated by wireless multimedia applications. The performance results on throughput, access delay and medium utilization have demonstrated that the protocol is able to achieve satisfying QoS differentiation for heterogeneous multimedia traffic. On the other hand the results have showed that IEEE 802.11e EDCA suffering from the low medium utilization due to the overhead generated by transmission collisions and back-off processes. 1

Optical Space Switches in Data Centers: Issues with Transport Protocols

A number of new architectures for data centre networks employing reconfigurable, SDN controlled, all-optical networks have been reported in recent years. In most cases, additional capacity was added to the system which unsurprisingly improved performance. In this study, a generalised network model that emulates the behaviour of these types of network was developed but where the total capacity is maintained constant so that system behaviour can be understood. An extensive emulated study is presented which indicates that the reconfiguration of such a network can have a detrimental impact on Transmission Control Protocol (TCP) congestion control mechanisms that can degrade the performance of the system. A number of simple scheduling mechanisms were investigated and the results show that an on-demand scheduling mechanism could deliver a throughput increase of more than ∼50% without any increase in total installed network capacity. These results, therefore, indicate the need to link the network resource management with new datacentre network architectures

Study of the Behavior of Titanium Alloys as the Cathode for Photovoltaic Hydrogen Production

CP-Ti and Ti-153 were adopted in this study to observe their electrochemical behavior in serving as the cathode for photovoltaic hydrogen production. The designed cyclic hydrogenation-solution heat treating processes were performed to increase the hydrogen uptake for both alloys. The results are as follows. (1) Both arsenic trioxide and thiourea showed hydrogenation promotive effect on CP-Ti, while thiourea was an inhibitor for Ti-153 under the applied conditions. (2) Arsenic trioxide showed hydrogenation promotive effect on both Ti-153 and CP-Ti in this study. (3) Ti-153 demonstrated superiority to CP-Ti when serves as the cathode for photovoltaic hydrogen production. The hydrogen mass payload for Ti-153 is 68 times larger than that for CP-Ti

Work in Progress – Establishing a Master Program in Cyber Physical Systems: Basic Findings and Future Perspectives

© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This paper reports on the basic findings and future perspectives of a capacity building project funded by the European Union. The International Master of Science on Cyber Physical Systems (MS@CPS) is a collaborative project that aims to establish a master program in cyber physical systems (CPS). A consortium composed of nine partners proposed the project. Three partners are European and from Germany, UK and Sweden; while the other six partners are from the South Mediterranean region and include: Palestine, Jordan and Tunisia. The consortium is led by the University of Siegen in Germany who also manages the implementation of the work packages. CPS is an emerging engineering subject with significant economic and societal implications, which motivated the consortium to propose the establishment of a master program to offer educational and training opportunities at graduate level in the fields of CPS. In this paper, CPS as a field of study is introduced with an emphasis on its importance, especially with regard to meeting local needs. A brief description of the project is presented in conjunction with the methodology for developing the courses and their learning outcomes

Knowledge, attitudes and practices with regard to the presence, transmission, impact, and control of cystic echinococcosis in Sidi Kacem Province, Morocco

BACKGROUND: This study is a component of a large research project on five major neglected zoonotic diseases (NZDs) including cystic echinococcosis and was undertaken in the Province of Sidi Kacem over a period of four years (April 2009-March 2013). METHODS: Questionnaires were administered at community level in a total of 27 communes and visits were made to all of the 10 abattoirs situated in the Province, to collect qualitative data on determinants of transmission for disease in humans and animals. More specifically, community knowledge, attitudes and practices related to cystic echinococcosis were assessed, as well as the extent to which local customs and behaviours may promote transmission. Abattoir infrastructure and practices, and their role in perpetuating disease transmission were also critically evaluated. RESULTS: The results show that only 50 % of people have heard of the disease, and of those, only 21 % are aware of the dog’s role in disease transmission. Sixty-seven per cent of respondents stated that dogs are fed ruminant organs deemed unfit for human consumption. Owned dogs have access to the family home, including the kitchen, in 39 % of households. The extent of this close proximity between humans and animals is even more pertinent when one considers that dogs are omnipresent in the community, with an average of 1.8 dogs owned per household. The unrestricted access of dogs to abattoirs is a huge issue, which further promotes disease transmission. CONCLUSION: This study would suggest that the high prevalence of cystic echinococcosis in humans and animals in Morocco is largely due to three factors: 1) abundance of dogs 2) engagement in risky behaviour of the local population and 3) poor abattoir infrastructure and practices. This has serious implications in terms of the socio-economic impact of the disease, especially for rural poor communities. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s40249-015-0082-9) contains supplementary material, which is available to authorized users