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Light sources in the wavelength range below 300nm have attracted extensive attention due to their applications in instrumentation and in disinfection of water, air and surface. Nitride-semiconductor-based, light emitting diodes (LEDs) are of especially great interest due to numerous advantages compared to conventional mercury lamps. Although significant progress of more than 9mW of quasi-CW power around 260nm at room temperature has been achieved from devices with Al x Ga 1−x N heterostructures pseudomorphically grown on native AlN substrate [1], those devices still have relatively low photon extraction efficiencies (estimated to be around 4%). In particular, half of the generated photons are directed towards the p-contact and absorbed by the smaller bandgap p-GaN. The other half of the photons, which are directed toward the exit surface, will experience absorption in AlN substrate due to point defects which create states within the bandgap of the AlN material. In addition, only a small fraction of those photons actually reaching the exit surface will escape due to the relatively large refractive index difference between AlN and air resulting in a narrow escape cone.

A skyline of a d-dimensional dataset contains the points that are not dominated by any other point on all dimensions. Due to its usefulness, a skyline query has recently received a considerable attention in several applications. However, as the number of dimensions increases, the probability of one point dominating another point becomes very low. In consequence, the number of points in the skyline becomes tremendous. To remedy this disadvantage, the k-dominant skyline has been introduced, which relaxes the domination relationship. Although the number of k-dominant skyline points is smaller than the number of skyline points, some important points in the dataset may be excluded from the result of a k-dominant skyline query due to the cyclic dominance relationship. With this problem in mind, we introduce a novel types of skyline queries, called the scored k-dominant skyline query. A scored k-dominant skyline is computed from skyline points by utilizing the notions of (i) k-dominance relationship and (ii) k-dominant score. We also present the search algorithm for the scored k-dominant skyline. Finally, we demonstrate the effectiveness of the scored k-dominant skyline through a set of simulations by using both real dataset and synthetic dataset.

Nowadays, XML has been favored as a means of sharing and distributing data, due to its open-architectural feature. XML-GL, a graphical query language for XML document, has the advantage of structuring and defining itself. By incorporating UML, an XML document can become object-oriented and can be represented by graphical means. This paper proposes an efficient query modelling of XML-GL using UML class diagram and OCL. In order to restrict properly the modeled object the Object Constraint Language(OCL) is used. By using proposed technique, we can store and manage XML documents as object-oriented data. And, we search XML documents more efficiently by a proposed query modeling technique using UML class diagram.

Search engine requirements increase as Internet use increases. Various types of forms must be requiring different search techniques. In case of academic writing (theses or professional scientific publications), quoted data from other documents must be appropriately handled. The occurrence of keywords in referenced documents, quoted in many documents in common, each highly weighted, attributes a disproportionately high weight to that keyword in the document. The more often a document is quoted, the more reliable the common portions of the referenced documents are ascribed to be. An algorithmic method of numerically ranking the importance of the pages is important to the search techniques. The quoted relations are sampled in the list of referenced documents and the statistics of the quoted relations were calculated. The technique renewing the keyword weight of referenced documents reflects the keyword weights of the quoted documents.

A series of business processes, based on Wf-XML, executing cooperatively and sharing information among customers, suppliers and business partners are used in electronic commerce. Wf-XML (Workflow-XML) is an asynchronous Web service protocol. A language defining XML-based protocol is suggested for the mutual linkage of the workflow engine. In this paper, the model is proposed to model the UML diagram on the resource model provided in Wf-XML to link different workflow engines. It facilitates understanding workflow for links and cooperation between enterprises.

With the rapid growth of mobile Internet, offering seamless connectivity and high-speed multimedia services in different types of wireless networks are important features in next generation wireless networks (4G networks). Many researchers envision that the 4G networks will consist of many radio access technologies which integrate into all IP-based networks while providing seamless handoffs across the heterogeneous wireless networks. Mobile IP is a prominent solution to handle mobile nodespsila movement in IP-based networks. However, Mobile IP suffers from long handoff latency since it is designed to support the macromobility of a mobile node. Therefore, it is necessary to devise a scheme that offers seamless connectivity during Mobile IP handoffs across the heterogeneous wireless networks. In this paper, we propose a client-based handoff management system for multi-networks to provide end-users with seamless connectivity across heterogeneous wireless networks. Our proposed system is designed as a common network interface at a client side and provides transparent services to IP/MIP layers regardless of used wireless technologies. With this system, we also present vertical handoff performance over a loosely coupled cdma2000/WLAN experimental test-bed. The experimental results show that our system enables a mobile node to handoff seamlessly across different types of wireless networks without any modifications to the existing IP/MIP stack and core network.

The properties of reactive hot melt polyurethane adhesives (RHAs) modified by dihydroxyl-terminated reactive acrylic macromonomers were examined and compared with those of RHAs modified with a non-reactive commercial acrylic copolymer. The melt viscosity and initial bond strength was increased when a portion of the polyols and tackifier was replaced by macromonomers or acrylic copolymers, which have higher glass transition temperatures. When RHA was modified by macromonomer, the storage modulus at low shear rate was reduced and set time was increased, which suggests that the chain entanglement was diminished by short-chain branches created by the macromonomers.

In this paper, we develop a fast and efficient face image browsing system on CE (Consumer Electronics) devices. Our system adopts three methods such as facial region de- tection and facial feature extraction, facial vector cluster- ing, and DB handling for face metadata. Given photos, a facial region detection algorithm is applied to each photo and then Gabor-Wavelet features of fiducial points in each detected face are extracted. Next, a facial vector clustering algorithm makes all the facial features, which corresponds to faces, be clustered in an appropriate manner. In general, a face recognition algorithm requires a registration proce- dure, i.e., a user should register face images as the gallery, but our system clusters daily photos automatically. Finally, the DB is updated in order to browse photos by face meta- data in realtime. This paper presents the developed algo- rithms of the three methods in detail and an easy and effi- cient user interface for a face image browsing system on CE devices with its snapshots.

In this paper, we present a simple way of estimating the integer frequency offset of orthogonal frequency division multiplexing (OFDM) system over a rapidly time-varying channel By utilizing the channel responses of neighboring subcarriers within one pilot symbol, the frequency offset estimator is derived. We show by simulation that the proposed estimator can accurately estimate the integer frequency offset with reduced computational burden.

The increase of mobile devices is addressing a mobility support to facilitate handovers of mobile devices. Mobile IPv6 (MIPv6) has been proposed by IETF to solve this problem in the Internet. But, in MIPv6, there is a time interval that a mobile node (MN) cannot send or receive any packets during the handovers. The time interval is long enough for packets to be lost so that it is intolerable to be used for real-time traffics. Therefore, it is necessary to find out the method to reduce a handover latency. For this reason, Fast Handovers for Mobile IPv6 (FMIPv6) protocol has been proposed to reduce the MIPv6 handover latency. In FMIPv6, there are two operation modes due to the unpredictability of MN's mobility; the predictive mode and the reactive mode. In this paper, we discuss two modes of FMIPv6 and compare their performance with MIPv6 in a real test-bed network. The performance result shows that FMIPv6 has better handover performance than MIPv6 does. But, it also shows that FMIPv6 still suffers from the handover disruption time due to the IEEE 802.11 MAC layer handover. I. INTRODUCTION

The need for the efficient handling of digital multimedia contents has increased tremendously as both home and mobile CE (Consumer Electronics) devices are equipped with large embedded storage such as hard disks or flash memories and are capable of handling enormous amounts of multimedia data. This paper presents Mint, an efficient multimedia contents management system for CE devices. It provides novel intuitive browsing and search interfaces by arranging multimedia data for various metadata. The system consists of the metadata extractors and the metadata core that are applicable to diverse hardware platforms and operating systems. Being applied to several CE devices has proved the usefulness of the system, especially for such devices as the digital TVs, set-top boxes and mobile phones.

We investigate the design of three low-complexity joint estimation algorithms (LJEAs) for frequency offset and carrier phase. The principles of the proposed LJEAs are based on the linear interpolation of correlation values in the main-lobe of the frequency and phase spectra of the received signal. With these algorithms, the estimation ranges, /spl Delta/f/sub d//spl times/T/sub s/, are less than 1/2N/sub s/ and 1/N/sub s/ which are comparable to conventional algorithms (f/sub d/ is the frequency offset, T/sub s/ is the symbol period, N/sub s/ is the burst length). The proposed LJEAs require only 2N/sub s/ or 4N/sub s/ complex multiplications which are very simple compared with conventional algorithms. Nevertheless the estimation accuracies of the LJEAs are as good as those of the conventional algorithms.

We integrate FinFET DRAM in sub-60nm feature size. To avoid severe passing gate effects in FinFET cell array, we introduce a local damascene gate structure. Threshold voltage control of the ultra thin body transistors is successfully achieved by adopting p+ boron in-situ doped poly-silicon gate on the FinFET cells. As a result, very stable and uniform operation of FinFET cells is realized. The local damascene FinFET with p+ gate can become a highly feasible mainstream DRAM technology for sub-60nm low-power high-speed devices

Mobile IPv6, which is a protocol being standardized by IETF for global IP mobility support, is expected to play a key role for future all-IP wireless networks. As the demands for delay sensitive real-time applications increase, the handover latency of mobile IPv6 becomes inadequate for these applications. There have been many proposals, such as fast handovers for mobile IPv6 (FMIPv6), to tackle this problem. However, FMIPv6 only concentrates on the protocol operation while it does not address other issues, such as radio access discovery and candidate access router discovery, that are critical to the handover performance of FMIPv6. Therefore, in this paper, we propose ARIP (access router information protocol), which performs a candidate access router discovery and a radio access network discovery in one protocol suite, to provide an efficient handover framework for MIPv6 and FMIPv6. ARIP is designed to cope with heterogeneous networks as well as homogeneous networks and to be closely coupled with FMIPv6 to provide an efficient handover operation. The performance evaluation of MIPv6, FMIPv6, and FMIPv6 with ARIP is performed in an actual network environment and the performance results show that FMIPv6 with ARIP gives the best performance in terms of handover latency

Documents based on Web have been increased very rapidly according to development of Web technology and the documents are very various in document structure and data type. Therefore, many intelligent information systems have applied document categorization method and semantic relation, which they developed to offer fit documents for the user. But information system in present is unable to offer fit information for personal interesting because of the lack of related knowledge which it specify relationship between concepts based on document content. Also there are unable to interpret the content of information resources due to the lack of knowledge. Therefore, in this paper we want to express hierarchical structure in according to concept degree of different structure and data type of document on Web using ontology method, which it is a specification of a conceptualization. Also we propose an algorithm to classify into the same cluster connected documents of similar meaning and reorganization use to fuzzy function and relation.

In Web-based information systems, separating business process logic from data and presentation logic creates a wide range of advantages. However, this separation is not easily achieved; even the data logic may be not separated from the presentation layer. Therefore it is necessary to define an abstract model for business processes, and then to map the model into a user's dynamic interface using the logic separating strategy. We present a stylesheet method for recognizing the process by extending the XSLT (Extensible Stylesheet Language Transformations) in order to achieve logic separation. This discussion provides an abstract specification of the business process and a scheme that extracts business model factors and their interactions using a Petri-net notation to show the business model from the process point of view. This is an attempt to separate the user interaction from the business process, that is, the separating of the dynamic components of the interaction Web document from the process structure of the Web applications. As a result, the development of service-oriented Web sites is made very easy and can be changed without affecting the other modules by virtue of the modularization concept. This facilitates development and maintenance of Web applications in independent manner.

We measured the characteristics of free space type 16/spl times/16 micro optical switches. Two types of micro mirrors to switch the laser beam were used. One is electrostatic actuation type and the other is mixing (electromagnetic+electrostatic) type. We could lessen the insertion loss by arranging the lenses in zigzag style which shorten the optical path. We compared the insertion losses of the optical switches with that of in-line type bench which has loss from the optical bench part only. The loss from the bench part was about 2 dB while the total insertion loss was about 5 dB and 12 dB for each mirror type. From this result, the main reason of the insertion loss was known to be from the mirror part. The switching time was about 15 msec. and the crosstalk was less than 50 dB for both types of switches.

Currently, automobile information systems lack a search service, because most of them aim at buying and selling. Thus, in this paper, we design and implement CISS (Car Information Service System) to provide efficient retrieval of information about automobiles. In CISS, we collect information about automobiles from the Internet and construct a lattice structure for efficient retrieval, and we provide retrieval convenience by implementing the "Car Browser" that permits gradual refinement of the index terms by browsing through the lattice graph and permitting keyword-based retrieval.

SGML is the international standard for digital documents to be used in fields like intranet, CALS/EC, and so on. On the other hand, there is a notable problem that in spite of having a similar structure and being conceptually the same kind of document, many SGML documents have different DTDs and are stored in different databases. We propose an algorithm that automatically unifies DTDs of these SGML documents using a tree structure and finite automata. Constructing the SGML document database to apply the proposed algorithm reduces the number of database accesses and increases the efficiency of information retrieval. It provides a more effective management and operation environment for SGML document databases.

Currently, the need for information retrieval systems that provide relevant information for specific users is emerging. However, the information retrieval systems of today are rather weak in the respect of reflecting the user's preferences and offering relevant ranked documents. Thus, we propose a method for filtering and document ranking using a user profile and latent structure analysis in order to provide more relevant results that are ordered by relevance. The user profile reflects the preferences of the specific user. We explain our method with examples.

The purpose of this paper is to present a new data structure for viewing large size medical images. The data structure is specifically designed suitable for lossless compression and viewing images interactively even when the channel bandwidth is limited as low as those of modems. Our data structure has been tested on several 2 K/spl times/2 K images by using various baud rates from 9600 to 28800. The thrust of this paper is two fold. First, browsing large image data files through limited bandwidth channels requires progressive transmission. Using conventional data structures, 1/3 more memory space is required to build the hierarchical structure. Our data structure utilizing two-dimensional DPCM embedded with hierarchy does not require extra memory space to build the structure for progressive transmission. The second important aspect of the data structure is the local zooming capability of the data for interactive viewing. This is achieved by rearranging the transmission order of image data so that the data in the region of interest can be transmitted first with the rest of the information on hold to be sent later.