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For an efficient resource reservation, mobility prediction has been reported as an effective means to decrease call dropping probability and to shorten handoff latency in wireless cellular networks. Several early-proposed handoff algorithms making use of a user's movement history on a cell-by-cell basis work on the assumption that the user's movement is restricted to the indoor locations such as an office or a building. These algorithms do not present a good performance in a micro-cell structure or a metropolis with complicated structure of roads. To overcome this drawback, we propose a new mobility prediction algorithm, which stores and uses the history of the user's positions within the current cell to predict the next cell.

As Service Oriented Architecture is expected to grow in the future e-business, web services are believed to be the ideal platform to integrate various business artifacts disparate platforms and systems. QoS(Quality of Service) of web services in terms of performance, reliability, and availability becomes the key issue when web services model complex and mission-critical applications. In this paper, we propose a simulation-based framework that enables web services to be composed based on their QoS properties. The proposed framework iteratively analyzes the QoS of the composite web services with multiple perspectives until the QoS requirements are met to various service users and providers.

Internet applications are increasingly being equipped with rich multimedia data. Most e-business development tools are quite good at authoring multimedia contents, however they lack explicit support for estimating the performance of the envisioned multimedia system at design time. W-CoSim (Web-based Hardware and Software Co-Simulator) is an EJB-based simulation tool used for validating the architecture and the performance of online multimedia systems at design time. WCoSim has four components: Modeler, Translator, Engine and Scenario. Users start from Modeler to describe systems architecture by means of a UML(Unified Modeling Language) deployment diagram, and then specify hardware & software performance parameters such as the size of audio and video data, execution delay and network topology. All information specified in the Modeler are sent to the Translator, and then automatically converted to Java code. Engine and Scenario are responsible to run the Java code and produce results in the form of text and graphs.

In recent years, due to the improvement in network speed, it has become possible to deliver diverse multimedia applications in near real time, and remote education is an area that can most benefit from such developments. In this way, large numbers of people have the opportunity to learn anywhere and at any time. With remote education, the proper use of multimedia components is an essential factor for achieving higher learning efficiency. However, the main prevailing tools used for contents creation do not explicitly provide a detail-level interface for combining possible media components. Most importantly, an interface that can coordinate the synchronization between hybrid media is required. In this paper, we present two additional types of teaching media, namely slides and handwriting. Moreover, we present an encoder interface that can combine these media with the conventional video streaming format.

The present paper reports more extensive and precise experimental results about the isotope shifts of Sm I in the 635 nm — 690 nm range by Doppler-free saturation absorption spectroscopy using a single-mode diode laser with a small linewidth. We measured newly the isotope shifts and hyperfine structures of 20 transition lines, which are mostly originating from the [4f 66s 2] 7 F J to [4f 66s6p] 9 D o 9 F o and 7 G o levels, with a resolution better than 8 MHz. The measured isotope shifts were resolved into mass shifts and field shifts by King plot analysis. Finally, we could obtain the changes in mean-square nuclear charge radii from field shifts, and they were compared with the previous results.