Semantic technologies for mobile Web and ... - Semantic Scholar

Semantic technologies for mobile Web and personalized ranking of mobile Web search results Evangelos Sakkopoulos Computer Engineering and Informatics Dpt. University of Patras, GR-26504, Rio Patras, Greece [email protected]

Abstract The semantic Web has brought exciting new possibilities for information access. Semantic Web is already adopted in several application domains. Our main objective is to critically present solutions using semantic Web technologies to provide successful mobile Web services. Aim of this work is also to introduce a novel semantically enriched personalization technique for the accelerating market of mobile environment introducing an enhanced data structure and web algorithm. A prototype has been implemented and proved effective. Furthermore, performance evaluation is also both encouraging and promising.

1. Introduction The Web was designed to be a universal space of information and mainly offers unstructured and semi-structured natural language data. The Semantic Web (Berners-Lee et al 2001, Dieter et al 2003, Sicilia 2006,) is specifically a web of machine readable information whose meaning is well defined. The ontologies (Dogac et al, 2002) for the Semantic Web are an emerging technology which offers a promising infrastructure as far as the harmonization of the heterogeneous representations of web resources is concerned. In this direction, ontologies offer a common understanding of a domain that can be a mean of communication among application systems and people. Semantic web technology is already adopted in several web based applications and solutions (Makris et al 2006, Sakkopoulos et al 2006, Kanellopoulos et al 2007, Sicilia et al 2006) marking in this way a new era in the Internet technologies. However, the application of such Web oriented and semantic Web based techniques is not straight forward in the domain of mobile solutions. Heterogeneous representations of web resources are common in the accelerating mobile web solutions area. In fact, according to the Gardner Group analysis (2004), there will be a high rate of change in the capabilities

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of mobile technology, infrastructure and telecommunications networks. No single technology will be suitable for all applications because each provides different trade-offs in terms of bandwidth, range and cost. Consequently, many types of short-range wireless networks will coexist in most organizations. Important considerations on the path to mobility are wireless LAN access and roaming between wireless LAN and mobile networks. These allow business users to wirelessly access corporate data at the office or at hotspots, such as airports or hotels, as well as in the wide area with mobile access. (Terziyan, 2001) Enterprise users are already able to have personalized, seamless access to enterprise applications and services from any place and any time, regardless of the devices employed, in order to make contextualized decisions in behalf of the enterprises using vendor proprietary solution as in (Terziyan, 2001). However, there is a need to standardize views to commercial operations and help users to reach consensus between any buyer and any seller about general and specific features of their business relationships. Towards this direction the multilevel profiling framework discussed in (Ericsson Enterprise, 2002) is able to manage ontologies, which are necessary for a semantic realization of mobile services. In this way it is possible to facilitate the concept of m-commerce as a public mobile electronic commerce, which is based on the assumption that every person in the society in some way more or less participates in public business process (public commerce or (pcommerce) in (Ericsson Enterprise, 2002). The main objective of this work is first to present an survey of promising approaches that unify semantic Web technologies with a number of different mobile operations such as location based services, time sensitive information seeking, entertainment, banking, payment, ticketing and personalization of searching. Furthermore, initial work on a novel approach that investigates the effects of semantic Web techniques for the personalization of mobile data centric solutions is presented. Aim of this work is to present an effective alternative that will provide limited and targeted searching/browsing results using semantics. In the sequel, the paper will be organized in the following sections. In section 2, we critically present, categorize and compare a number of semantically enriched solutions for mobile applications and services, in the new semantic based context. In section 3, we introduce a novel algorithmic approach and a prototype that personalizes effectively the query results for mobile environments using an enhanced flavour of biased skip list data structure and

Semantic technologies for mobile Web and personalized ranking of mobile Web search results 3

ODP categorical metadata in the case of bursty access patterns. Finally, section 5 concludes the paper and presents future steps.

2. The new context of mobile web There will be a high rate of change in the capabilities of mobile technology, infrastructure and telecommunications networks. No single technology will be suitable for all applications because each provides different trade-offs in terms of bandwidth, range and cost. Consequently, many types of short-range wireless networks will coexist in most organizations. (Gardner Group, 2004) Important considerations on the path to mobility are wireless LAN access and roaming between wireless LAN and GPRS networks. These allow business users to wirelessly access corporate data at the office or at hotspots, such as airports or hotels, as well as in the wide area with GPRS access. (Ericsson Enterprise 2002) Table 1. Comparative list of semantic approaches implemented for the mobile web

Authors

Title

Key Issues

Contribution

ƒData clustering ƒSemantic caching mechanism which query based and allows data to be cached as a collection not item based of possibly related blocks, each of ƒBetter response which is the result of a previously time, cache hit rate evaluated query ƒBetter ƒTransforming projection-selection answerability queries to reuse cached data blocks ƒCache replacement techniques based on the semantics of cached data Qun Ren Using semantic ƒFacilitate ƒSemantic cache replacement strategy Margaret H. caching to disconnection Furthest Away Replacement (FAR), Dunham manage location ƒImprove system which utilizes the semantic locality in dependent data in performance terms of locations mobile ƒConcept of moving direction as a factor computing for cache replacement James D. ƒTakes advantage of new metadata Wireless spatio- ƒPerforming Carswell efficient mobile standards to enable semantic, user, and semantic Keith Gardiner transactions on context-aware device adapted transactions on Marco queries. multimedia datasets multimedia ƒUpdating of a ƒPresentation of system MoCHA Neumann datasets context-sensitive (Mobile Cultural Heritage Adventures) multimedia spatial database. Ken. C. K. Lee Semantic query H. V. Leong caching in a mobile environment

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ƒIntroduction of a ƒA framework of dynamic semantic Pei-Hung Dynamic Hsieh semantic location new location model location modeling (DSLM) that (LM represents the exemplifies certain integration of Soe-Tsyr Yuan modeling in enterprise business models mobile enterprise inclusive objects and their ƒA proposed location model that applications relationships in a surmounts the problems encountered in space). static location models Haibo Hu Dik- Semantic ƒSemantic location ƒThe result of the proposed modeling Lun Lee (Hu et Location model which process is a location hierarchy and an al 2004) Modeling for preserves topology exit hierarchy, which completely Location and distance preserve the topology and distance Navigation in semantics to semantics between locations. Mobile support location ƒSound theoretical foundation to define Environment navigation the model ƒFacilitation of ƒSeries of novel algorithms to construct programmatic the model. model construction ƒPresentation of real modeling process example. and maintenance Norman M. A semantic web ƒDirect application ƒIntroduction of customizable agents Sadeh environment for of Semantic Web mechanisms capable of (semi-) Ting-Chak context-aware m- technologies for automatically discovering and Chan commerce context-aware accessing user personal resources (e.g. Linh Van, mobile services. calendar, location tracking OhByung functionality, food preferences) and Kwon Web services. Kazuaki Takizawa Ken C.K. Lee Semantic Data ƒSelf answerability ƒIntroduction of three semantic-based Hong Va Access in an of queries. broadcasting schemes in associating Leong Asymmetric descriptions with clusters of data items, Antonio Si Mobile to improve the self answerability. Environment ƒComparison of performance with the base case of attribute-based broadcast scheme through a simulation model. Jason J. Jung Template-Based ƒBound usage of e- ƒIntroduction of framework to extract GeunSik Jo mail user-relevant pieces of information E-mail (Jung et 2003) Summarization communication from each e-mail text. ƒAutomatically generated templates bandwidth. for Wireless ƒSemantic based on semantic tagging are applied Devices. summarization of to discriminate which parts of the text wireless e-mail should be extracted. ƒIn experiments, this system has shown an average removal of 74% redundant textual information and a maximum accurate filling of 93% of the template slots by collecting e-mails from DBWorld.

Semantic technologies for mobile Web and personalized ranking of mobile Web search results 5 ƒCombination of the user's notion of relevance together with semantic author annotations and structural document characteristics. ƒUse of XML technology documents that are automatically adapted to fit both personal user profiles and device constraints Young-Hoon Mobile Q&A ƒUse of popular ƒMobile Q&A ontology for inference Yu Agent System Q&A boards for execution by using the ontology that Based on the Jason J. Jung sharing consists of RDF and RDFS, i.e. the Kyoung-Sin Semantic Web in information. knowledge representation language of Noh Wireless Internet semantic web and the similarity GeunSik Jo measure algorithm on the class (Yu et al 2004) property Akiyo WebCarousel: ƒMobile web ƒWeb search results are shown by Nadamoto Automatic searching synthesized speech synchronized with Hiroyuki Presentation and ƒMobile web related images in a repeated manner by Kondo Semantic carousels. browsing Katsumi Restructuring of ƒDynamic reorganization of search Tanaka Web Search results into carousels is done by Result for Mobile discovering 'semantic' relationships Environments between Web pages Panu Korpipää, An Ontology for ƒEfficient utilisation ƒOntology, i.e. semantic interface, to the Jani Mobile Device of the information sensor data provided by a mobile Mäntyjärvi Sensor-Based gained from the device. Context sensors embedded Awareness in the devices. Ken C. K. Lee A Semantic ƒDatabase ƒSemantic-based broadcast approach Hong Va Broadcast communication to which attaches a semantic description Leong Scheme for a numerous mobile to each broadcast unit, called a chunk, Antonio Si Mobile clients. to facilitate supplementary querries to Environment the DB. based on ƒHeuristic to schedule the broadcast Dynamic order of the chunks to improve the Chunking tuning time and access time. ƒNew metric called a data affinity index. Belle L. Tseng Video ƒVideo ƒAn MPEG-7 compliant annotation Ching-Yung Summarization summarization and interface ƒSemantic summarization middleware Lin and semantic ƒReal-time MPEG-1/2 video transcoder John R. Smith Personalization personalization on PCs for Pervasive content delivery. ƒApplication interface on color/blackMobile Devices and-white Palm-OS PDAs Zuji Mao ƒNext-generation ƒMultiTree database architecture A distributed Christos global mobile consists of a number of database database Douligeris roaming support. subsystems, each of which is a threearchitecture for level tree structure and is connected to global roaming in the others only through its root. next-generation ƒMemory-resident direct file and T-tree, mobile networks are proposed for the location databases.

M. Wagner W. Kießling W.-T. Balke

Progressive Content Delivery for Mobile EServices

ƒProgressive delivery of Web documents in mobile Internet Services

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Niina Mallat Matti Rossi Virpi Kristiina Tuunainen

ƒAdopting new and ƒInvestigates emerging mobile financial New architectures for innovative mobile applications, including both mobile financial payments and banking services, financial showing how the new financial services: Mobile applications and services can be deployed in mobile banking services service provisioning networks and identifying the main methods. players in the emerging mobile financing value chain.

Enterprise users are able to have personalized, seamless access to enterprise applications and services from any place and any time, regardless of the devices employed, in order to make contextualized decisions in behalf of the enterprises using vendor proprietary solution as in (Ericsson Enterprise 2002). However, there is a need to standardize views to commercial operations and help users to reach consensus between any buyer and any seller about general and specific features of their business relationships. Towards this direction the multilevel profiling framework discussed in (Terziyan 2001) is able to manage ontologies, which are necessary for a semantic realization of mobile services. In this way it is possible to facilitate the concept of m-commerce as a public mobile electronic commerce, which is based on the assumption that every person in the society in some way more or less participates in public business process (public commerce or (p-commerce) in (Terziyan 2001). Additionally, in (Korpipää et al 2003) the ontology introduced promotes the rapid development of mobile applications, more efficient use of resources, as well as reuse and sharing of information between communicating entities. In a more technical paradigm, to deliver multiple copies of database information, partial broadcasting is usually adopted. When a broadcast session contains only a subset of the database items, a client might not be able to obtain all its items from the broadcast and is forced to request additional ones from the server on demand. Semantic-based broadcast approach (Lee et al 2000) attaches a semantic description to each broadcast unit, called a chunk. It allows a client to determine if a query can be answered entirely using a broadcast as well as defining the precise nature of the remaining items in the form of a “supplementary” query. Furthermore, advances in spatially enabled semantic computing can provide situation aware assistance for mobile users. This intelligent and context-aware technology presents the right information at the right time, place and situation by exploiting semantically referenced data for knowledge discovery. (Carswell et al 2004). Towards the improvement of self-answerability of queries, extensive experimentation in (Lee et al 2002) shows that the adaptive chunking scheme appears to perform slightly better among the three chunkbased semantic broadcast schemes.

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Semantic web technologies have already joined multiple implementations of current m-business reality. Community has shown interest in several semantic aspects of mobile technology. In the sequel, different services coupled with semantic technologies are presented. Location-Based Services. Location-based services (LBS) are information services that exploit knowledge about where an information device user is located. The next-generation mobile network will support terminal mobility, personal mobility, and service provider portability, making global roaming seamless. A location-independent personal telecommunication number (PTN) scheme is conducive to implementing such a global mobile system (Mao et al 2004). There is a need for incorporation of design and performance of highthroughput database technologies into the forthcoming mobile systems to ensure that future systems will be able to carry efficiently the anticipated loads. Exploitation of the localized nature of calling and mobility patterns, the proposed architecture effectively reduces the database loads as well as the signaling traffic incurred by the location registration and call delivery procedures. Through the Location Model Platform of information sharing, enterprises are empowered to discover the potential business partners and estimate the values of their cooperation, enhancing their competitive advantages in a market when appropriate partnerships are formed.(Hsieh et al 2003) Semantic caching scheme is used to access location dependent data It introduced the concept of moving direction as a factor for cache replacement (Ren et al 2000). According to the client’s velocity, all the data records in the cache can be divided into two sets. One contains all the objects that are in the direction of the client’s movement, named “in” set. The other contains the rest of objects, named “out” set. Time-Sensitive Information. M-commerce can be effective for information such as sports results, flight information and tourist information. An example of the latter is MoCHA (Mobile Cultural Heritage Adventures) that allows the mobile cultural heritage consumer to explore a personally tailored view of Dublin's treasured artefacts, historical events and districts in an interactive and intuitive way directly on their spatially enabled PDA (Carswell et al 2004). In order to boost delivery of such information, proposed mechanisms exist for transforming projection-selection queries to reuse cached data blocks (Ken et al 1999). This avoids transmitting unwanted data items over low bandwidth wireless channels. Another example of assistance to users in carrying out different tasks such as planning an evening out, organizing a study group or filtering incoming messages can be found in (Sadeh et al 2003). In WebCarousel (Nadamoto et al 2001) the web search results are shown by

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synthesized speech synchronized with related images in a repeated manner by carousels. Entertainment. Consumers can leverage m-commerce for uses such as downloaded games (mostly Java) and favourite web page links. Music and Video delivery have potentials but need at least 3G performance and lower prices to become attractive. Progressive delivery of Web documents in mobile Internet Services proposed in (Wagner et al 2002) allows focused delivery of entertainment data in a cost-effective sense. Use of XML technology documents that are automatically adapted to fit both personal user profiles and device constraints may enhance the web browsing entertaining experience. A case of video delivery enhanced by semantic annotation is (Tseng et al 2002). A Video annotation tool, VideoAnn, can be used to annotate semantic labels associated with video shots and to annotate the video content with the units of temporal shots or spatial regions. The clients can access the summarized video based on their preferences, time, keywords, as well as the transmission bandwidth and the remaining battery power on the pervasive devices A new way of organizing Web search results is found in (Nadamoto et al 2001). A way of viewing those results passively in the mobile environment which has limited display and limited interaction is also presented. Banking, Payment and Ticketing. A broad overview of mobile payment (micropayment and macropayment) and mobile banking services is presented in (Mallat et al 2004). Modest success has been realized in applications that have an element of mobility and immediacy, such as parking, road congestion charging or commuting.

3. Personalization for the mobile web searching In this section, we introduce a new approach that personalizes the web searching results in mobile environments taking advantage of the web pages’ categorical metadata (dmoz- ODP). We particulary focus on the case of bursty web search patterns. Our aim is to present a more effective algorithm to rank web search results for mobile environments. It is difficult for mobile gadgets to display ordinary the web search results, as they usually have limited dimensions in their displays. Our approach achieves to narrow down the possible and available results in order to facilitate the final choice made by the user. When the results matching a user’s query are of a size, it is possible in most cases to complicate their manipulation. As a consequence the typical web search engine results should be further processed, so that they are presented in a way that can help users evaluate all available alternatives and perform relative comparisons before proceeding to further browsing. This is

Semantic technologies for mobile Web and personalized ranking of mobile Web search results 9

especially the case where the mobile devices are utilized as shopping assistants while searching in the Internet and perform online shopping (Haübl et al 2000). Personalization on search results has already been studied previously in a number of cases (Jansen et al 2000, Henziger 2003). Successful cases also include techniques where semantic/ metadata pre-processing of the results has been utilized effectively. The latter cases include techniques that map user queries on semantic categories (Liu et al 2002) or alternatively group the results into categories (Dumais et al 2001). In the work of Makris et al 2007 an novel procedure has been introduced to personalize search results based on their semantic correlation as this derives from the ODP (dmoz.org) categorical metadata assigned to each web page result. The Open Directory (ODP) powers the core directory services for the Web's largest and most popular search engines and portals, including AOL Search, Google, Lycos, HotBot, and hundreds of others.( dmoz.org/about.html).

3.1 Bursty web category browsing pattern In bursty cases, a few web pages results’ categories get “hot” for short periods of time and are accessed very frequently in a limited temporal space. Such patterns have been also observed in various Internet applications in a number of studies (Zhou et al 2004, Ergün et al 2001, Lin et al 1997). In bursty web search pattern cases, the user attempts to find specific results that belong to limited categories of interest within a short time period. As a consequence an efficient retrieval and storing mechanism is needed to keep the users’ personalized categories and frequent results.

3.2 The proposed algorithm There are a number of self-adjusting or biased data structures (Sleator et al 1985) that are designed to exploit such biases, and provide similar (amortized) search times (eq. 2,3). These data structures perform complex balancing schemes which hinder their practical performance. In this work, we deploy and port a new flavour of the biased skip list by Ergün et al 2001 (BSL – section 3.3) that avoids such balancing operations, and employs a novel lazy maintenance scheme to provide fast insertion and deletion of categories in the preference list of the users’ search results.

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As a consequence, whenever we refer to bursty accesses to web search results, we implicitly detect the specific category (or group of categories closely related at the ODP graph) that the browsed page belongs to. (e.g. Retailers for Storage devices for which the ODP respective category is Top-ComputersHardware-Storage-Retailers or Pizza in my neighbourhood -island Corfu- for which ODP categorizes the results in Regional-Europe-Greece-PrefecturesCorfu-Business and Economy-Restaurants and Bars). In order to construct our user profiles on the enhanced BSL logic, we utilize the idea of (Makris et al 2007) for a personalized graph of ODP categories per user. Specifically, we refine the BSL approach introducing a “biasing category results in favour of latest frequently visited category” procedure (section 3.4). As a result, we achieve to narrow effectively the selection list whenever a user is actively searching repeatedly in semantically close category results. The proposed algorithm approach includes the following steps depicted at figure 1. 1. While (!Categories of interest chosen == true) 2. Implicitly or explicitly store in user profile the pages and respective categorical metadata of search results browsed 3. Construct personalized subgraph G’ from the ODP categorical graph G assigning a weight β(v) to each category v for each user utilizing function (eq. 1) 4. Store personalized subgraph on Biased Skip List data structure 5. While (Exists(bursty web category accesses pattern) == true) 6. Bias category results in favour of latest frequently visited category utilizing (eq. 4) 7. If session == alive 8. return to 3 and further update personalized G’ 9. else //(session lifespan ends) 10. return to 1 // for a new user session Fig. 1. Personalization algorithm for mobile devices in bursty access pattern cases.

The authors in (Makris et al 2007) proposed different methods for constructing the personalized subgraph G’ of the ODP categorical metadata. The main idea is to keep a user-based personalized version of the ODP categories graph G carefully selected and as limited as possible. This subgraph can be constructed by tracking user preferences implicitly (using the visited web page results) or explicitly (asking the user to choose categories of interest per session). Every web page category v in the personalized G’ graph is assigned a semantically based weight β(v)>0. These weights are used in order to post-categorize pages returned to the end user. The most practical of

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the proposed approaches is called “semi-offline”, where category weights are only updated after a number of user web searching sessions (i.e. per day or per week). Category weights are updated according to the following relation:

β (v) = β (v) +

out deg ree( v )

in deg ree( v )

i =1

i =1

∑ d (v, vi )β (vi ) +

∑ d (vi , v)β (vi )

(1),

where d(u,v) = 1/outdegree(u,v) (Makris et al 2007).

3.3 Biased skip lists BSL require O(n) space, and can be constructed in O(n) expected time when categories are given in sorted order. The categories are ranked 1 through n according to how frequently or recently they have been accessed. Searching for a category k takes O(log r(k)) expected time

(2),

where r(k) denotes the rank of the category in each user profile. Because the maximum rank is n, all operations have O(log n) expected worst case

(3),

as with Skip Lists and other efficient data structures – which is optimal. In (Ergün et al 2001) the most recently accessed (MRA) scheme is utilized in the cases of highly bursty access patterns. Eq. 2,3 can be further improved in the cases where categories do not remain in the data structure for a long time, but instead have short lifespans. Once inserted, these categories are rapidly accessed a few times, then deleted after a short period. As a result, their MRA ranks always remain close to 1. To facilitate more efficient implementation of insertions and deletions, we adopt (Ergün et al 2001) who proposed a lazy updating scheme of levels and allow flexibility in class sizes. The MRA implementation of BSL facilitates insertion or deletion of a category k in amortized O(log rmax(k)) time, where rmax(k) is the maximum rank of category k in its lifespan. In bursty patterns, when a category is hot, it is accessed a large number of times rapidly. This means that, according to the MRA scheme, the category maintains a small rank compared to the number of keys in the data structure. Thus, having the running times depend on the rank rather than the total number of categories yields significant gains.

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3.4 Biasing category results in favour of latest frequently visited category In the case the bursty event, the accessed category is ranked in the user profile biased according to the following weight βnew. When the category is already first in the rank no updates are needed. k

β newx = β currentx +

∑ ( 2 • existsβ (i) ) i =1

i

2k +1 − 3

(

)

• β newmax − β current x (4)

where exists(β(i)) equals 1 if the category is chosen in the ith access during the bursty pattern visits. Therefore, it exists whenever a new access is made to the category at the ith visit, where i∈[1,m] and m equals the total number of visits in the current bursty web access session.

3.5 Prototype on Personal digital assistants and initial results. A prototype has been delivered at the Windows Mobile 5 platform and .NET and browser scripting technologies have been utilized. The proposed algorithm has been used to personalize the Google and Google Directory search results as shown in the figure 2 below. Notice that the re-ranked results include indication of original ordering/ranking delivered by Google search engine before personalization. We have to mention that the presented approach is still on-going work. However the initial application performance results are promising (the inline browser re-ranking of results and implementation of the enhanced BSL is feasible and effective on the limited resources of a WM5 PDA) and evaluation is encouraging. We have evaluated the performance of our approach as well as its effectiveness in personalizing the search results by measuring how higher the web page results of preferred categorical metadata are re-ranked with respect to their initial Google ranking. The evaluation has been performed using synthetic data according to the following bursty web access scenario parameters: a) 8-10 categories from the top-3 ODP category levels were chosen for each user profile as preferred,

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b) a two word query was randomly chosen (= a web page title randomly chosen from the pages listed in the categories chosen as preferred) b) during the burst session, 10 web search results were chosen as preferred for each random query. In the end, the proposed solution in the cases of bursty access patterns was overall promoted the relative results with 3.4 higher rankings on average in 10 users for 100 random queries each. This means that the user would have found the requesting results higher in the ranking list, easing in this way its browsing experience in the mobile device. However, further evaluation is planned using real-life subjects/testers. For the overall evaluation of the proposed system, user testing is considered as the most appropriate method as in most web application evaluation cases only real end-users along with advanced users are in position to provide valuable feedback, identify problems and suggest modifications. We also plan a series of extensive evaluation sessions using full lab observation with groups of test users corresponding to the types of target groups, intending to have more precise results on the systems’ performance. We will also prepare a series of more elaborate questionnaires in order to identify system the systems’ usability and performance possible drawbacks.

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Fig. 2. Personalization of Google Directory searching on Windows Mobile 5 for Pocket PC

4. Conclusions and Future Steps Semantic web technologies have already served in a number of cases as a catalyst for improving the mobile application browsing experience. An analytic review of available semantic based solutions have been presented as well as categorized in location-based services, time sensitive service, entertainment services, small payment and ticketing. Metadata can be considered the semantic web’s cornerstone. In fact, categories-metadata are already available for a large number of web search results through the Open Directory Project. Our focus is to utilize the former metadata in order to provide improved experience in the limited display space and keyboard capabilities of the mobile environments. It is even more important than in desktop browsing, to be able to personalize effectively search results in mobile web. Personalization in this context means to narrow down the available search result choices using biased re-ranking based on the metadata and the users’ preferences. We have introduced a novel approach that personalizes effectively the search results in the case of bursty web search access patters for the first time to the author’s best knowledge. In our approach, we have deployed a new flavour of a biased skip list approach

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specialized for bursty access patterns in the case of re-ranking search results using their ODP based metadata-categories. A prototype has been introduced and initial results and performance evaluation have been encouranging and promising. Future steps include further experimentation and performance evaluation using subjects. A practical implication that has also to be considered is the presentation of long and overlapping names of ODP categorical metadata in the search results. Hashing techniques are investigated to overcome this implication. Furthermore, improving more the personalization combining ODP categories with user-preferred ontologies will be studied.

References Berners-Lee, T., Hendler, J., and Lassila, O. (2001). The Semantic Web, Scientific American, Vol. 285, No. 5, pp. 34-43. Carswell, J.D., Gardiner, K., Neumann, M. (2004): "Wireless spatio-semantic transactions on multimedia datasets", Proceedings of the 2004 ACM symposium on Applied computing, 2004, pp. 1201 – 1205 Dieter, F., Hendler, J., Lieberman, H., and Wahlster, W. (2003). Spinning the Semantic Web. Dogac, A., Laleci, G., Kabak, Y., and Cingil, I. (2002). Exploiting Web Services Semantics: Taxonomies vs. Ontologies, IEEE Data Engineering Bulletin, Vol. 25, No. 4. Dumais, S.T., Cutrell, E.and Chen, H., Bringing order to the web: Optimizing search by showing results in context. In Proceedings of CHI'01, Human Factors in Computing Systems, April 2001, pp. 277-283 Ergün, F., Mittra, S., Cenk Sahinalp, S., Sharp, J., Sinha, R.K.: A Dynamic Lookup Scheme for Bursty Access Patterns. INFOCOM 2001, pp. 14441453 Ericsson Enterprise, (2002). The path to the Mobile Enterprise, Available at http://www.ericsson.com/enterprise/library/white_papers/Mobile_enterpri se.pdf Gardner Group, (2004), The mobile business value scenario, Winning in the Mobile and Wireless World, Strategic Planning Series, Chapter 2. Haübl, G., and Trifts, V., “Consumer Decision Making in Online Shopping Environments: The Effects of Interactive Shopping Aids”, Marketing Science 19 (1), 2000, pp. 4-21. Henzinger, M., Algorithmic Challenges in Web Search Engines, Internet Mathematics 1, 1, 2003, pp.115-126

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