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Purpose: Rapid sintering technology has become one of the most direct methods for shortening the manufacturing time of zirconia restorations. This study aimed to explore the aging resistance of rapid-sintered 5 mol% yttria-partially-stabilized zirconia (5Y-PSZ).Methods: Specimens were made from two types of 5Y-PSZ material and subjected to rapid sintering (RS) and conventional sintering (CS). After in vitro aging for 5 h, morphology observation, grain size measurement, and phase composition analysis were performed. The mechanical properties were evaluated by biaxial, three-point flexural tests, and the Vickers microhardness test. Results were analyzed by 3-way ANOVA.Results: Both the RS group and the CS group had a dense microstructure. The tested zirconia ceramics had different grain sizes, which were affected by the interaction between the sintering method and aging. Both groups revealed the same characteristic peaks of the cubic phase after aging. Regardless of the sintering method used, there was no significant difference in the mechanical properties of the tested zirconia before and after aging.Conclusion: The rapid-sintered 5Y-PSZ materials had a microstructure, phase composition and mechanical properties similar to those of conventional sintered materials. The characteristics of the materials prepared using the two sintering methods did not change significantly after aging. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jss.2006.09.041 Byline: Chun-Chuan Yang, Yung-Chi Wang, Chih-Wen Tien Keywords: Synchronized multimedia; SMIL2.0; Real-time synchronization model Abstract: A novel synchronization model namely Extended Real-Time Synchronization Model (E-RTSM) for modeling SMIL2.0 temporal behaviors is proposed in this paper. E-RTSM deals with event-based/non-deterministic synchronization as well as schedule-based synchronization in SMIL2.0. Converting of the temporal relationship of a SMIL2.0 document to E-RTSM is presented. Moreover, design of the E-RTSM-based data-retrieving engine for SMIL2.0 presentations is also proposed in the paper. The data-retrieving engine estimates the worst-case playback time of each object at the parsing stage and applying an error compensation mechanism at run-time to adjust the estimated playback time as well as the schedule of the fetching requests for data retrieval. Performance measurements from the real implementation of the E-RTSM-based data-retrieving engine for SMIL2.0 presentations have demonstrated the efficiency of the proposed technique. Author Affiliation: Multimedia and Communications Laboratory, Department of Computer Science and Information Engineering, National Chi-Nan University, 1, University Road, Puli, Nantou County 545, Taiwan, ROC Article History: Received 25 November 2005; Revised 30 September 2006; Accepted 30 September 2006

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.comnet.2006.10.007 Byline: Chun-Chuan Yang (a), Chun-Shian Tsai (b), Junn-Yen Hu (a)(b), Tzu-Chien Chuang (a)(b) Keywords: 802.16; BWA; Mobility management; Wireless overlay network; Vertical handoff Abstract: In this paper, we investigate the characteristics of IEEE 802.16 and conclude that it is better to equip BS (base station) and SS (subscriber station) with Layer 3 functionality. Therefore, an 802.16 network can act as the backbone network of different subnets for better deployment. Based on the two IEEE Specifications, 802.16-2004 and 802.16e, we propose two kinds of paradigms of the 802.16 network technology for mobile networking. In the first paradigm, a novel concept called middle-domain mobility management in between macro- and micro-domain for 802.16-2004 is proposed. The management scheme of middle-domain is designed to accommodate different micro-mobility protocols in an 802.16-2004 network environment. Moreover, a mathematical analysis and simulation study are presented for performance evaluation. In the second paradigm, by comparing with traditional overlay networks (e.g. GPRS/WLAN), we have found that the characteristics for the 802.16e/802.11 overlay network are actually different from traditional overlay networks. To provide more efficient vertical handoff, a novel protocol called speed-based vertical handoff scheme (SVH) is proposed. A Simulation study has demonstrated that SVH can achieve a better performance than its WLAN-first counterpart in terms of less signaling and fewer packet losses. Author Affiliation: (a) Department of Computer Science and Information Engineering, National Chi Nan University, #1, University Road, PULI, Nantao 545, Taiwan, ROC (b) Department of Computer Science and Information Engineering, Chung Chou Institute of Technology, Taiwan, ROC Article History: Received 2 May 2006; Revised 4 October 2006; Accepted 13 October 2006 Article Note: (footnote) [star] This work was supported in part by the National Science Council, Taiwan, R.O.C., under grant no. NSC94-2219-E-260-004.

We propose an enhancement of Mobile IP (MIP) called MIP with Home Agent Handover (HH-MIP) to enjoy most of the advantages of Route Optimization MIP (ROMIP) but with only a small increase of signaling overhead. In HH-MIP, the concept of Temporary HA (THA) is proposed and the mobile host (MH) registers the new CoA with its THA rather than its original HA. Since the THA of an MH is selected to be close to the current location of MH, HH-MIP reduces the handoff latency and shortens the signaling path of registration as well. Moreover, HH-MIP adopts an aggressive approach in selecting THA for an MH, that is, whenever an MH is moving away from its HA or previous THA, the MH triggers the handover of THA. Theoretical analysis demonstrates that the proposed scheme enjoys small handoff latency as well as routing efficiency, and the signaling cost of the proposed scheme is significantly less than that in ROMIP.

LTE-Advanced (LTE-A) offloading is concerned about alleviating traffic congestion for the LTE-A network, which includes the core network and the radio access network (RAN). Due to the scarcity of the radio resource, offloading for the LTE-A RAN is more critical, for which an efficient way is to integrate Wi-Fi with LTE-A to form a heterogeneous RAN environment. An LTE-A UE (User Equipment) with the wi-fi interface can therefore access the Internet via an LTE-A base station of Evolved Node B (eNB) or a wi-fi Access Point (AP). In this paper, wireless network selection for UEs with delay-sensitive traffic in the heterogeneous RAN of LTE-A and wi-fi is addressed. Based on the queueing model of M/G/1, a novel network selection and offloading scheme, namely Delay-Sensitive Network Selection and Offloading (DSO), is proposed. The average system time at LTE-A eNBs and wi-fi APs calculated according to M/G/1 is used for network selection as well as offloading operations in DSO. The benefit of DSO in terms of satisfying the delay budget of UEs and load balancing is demonstrated by the simulation study. [ABSTRACT FROM AUTHOR]

By introduction of relay nodes, LTE-Advanced can provide enhanced coverage and capacity at cell edges and hot-spot areas. The authors have been researching the issue of power saving in mobile communications technology such as WiMax and Long Term Evolution (LTE) for some years. Based on the previous idea of load-based power saving, two strategies each with associated schemes to integrated relay nodes and user equipment in power saving are proposed in the paper. Simulation study shows the benefit of the proposed schemes in terms of better power saving than the standard-based scheme at the cost of moderately increased delay. Extended discussion about the impact of different load distribution among user equipments and the impact of a worse backhaul link on power saving is also presented in the paper. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]