Earticle

Metro Ethernet has recently attracted remarkable attention due to its simplicity and low cost. Although Ethernet is the dominant technology in the Local Area Network (LAN) which usually handles small number of nodes, when deploying in Metropolitan Area Networks (MANs), it faces certain challenges. One major challenge is its broadcasting based address resolution scheme. A broadcast-based address resolution scheme triggers many broadcast messages in a network, and hence make the Ethernet unscalable. This paper proposes a cache scheme, called Caching on Forwarding Table (CFT), to reduce broadcast messages for Metro Ethernet. CFT caches end user's Address Resolution Protocol (ARP) entries by inserting an IP address in each forwarding entry. If an ARP request is answered by a cached entry, the broadcast is stopped. Hence CFT can significantly reduce the broadcast messages in the network. We also discuss how to cache ARP entries in a Metro Ethernet using End User Enabled MAC-in-MAC (MiM) scheme. The simulation results show that CFT can effectively decrease the communication messages for address resolution and make Metro Ethernet more scalable.

Objectives: The purpose of this study was to identify the effects of aromatherapy on an anxiety of nursing students at the first time practice about intravenous injection. To learn intravenous injection skill is one of the most stressful situations for the nursing students. We expected that aromatherapy used as nursing intervention will be helpful to decrease their anxiety. Method: Subjects of this study were fifty-five nursing students who attended in fundamental of nursing class. The experiment and data collection were conducted on May 25, 2010. Anxiety was measured by five variables, systolic and diastolic blood pressure, pulse, McNair's tension-anxiety scale, and VAS for anxiety. Treatment of this study was aroma lamp inhalation using lavender, chamomile, and sweet-orange essential oil. Data were analyzed using PASW. Results: There were significant differences in pulse between experimental and control groups just before practice. And degree of increase in systolic blood pressure and pulse rate were significantly low in the experimental group. Conclusions: Aroma lamp inhalation, an easy to use intervention was useful to decrease anxiety in practice of intravenous injection.

The quality of spinning forming parts is closely related to the selection of spinning forces. In this paper, we use the finite element numerical simulation technology, establish a three-dimensional model and carry out a finite element analysis, to realize the simulation of variations of tube spinning parts’ spinning forces with composite bars. This method provides a theoretical basis for selecting an accurate spinning force, and has a great significance for improving the spinning forming quality and productivity.

Real-Time (RT) applications, which manipulate important volumes of data, need to be managed with RT databases that deal with time-constrained data and time-constrained transactions. In spite of their numerous advantages, RT databases development remains a complex task, since developers must study many design issues related to the RT domain. In this paper, we tackle this problem by proposing RT design patterns that allow the modeling of structural and behavioral aspects of RT databases. We show how RT design patterns can provide design assistance through architecture reuse of reoccurring design problems. In addition, we present an UML profile that represents patterns and facilitates further their reuse. This profile proposes, on one hand, UML extensions allowing to model the variability of patterns in the RT context and, on another hand, extensions inspired from the MARTE (Modeling and Analysis of Real-Time Embedded systems) profile.