• Journal of Intelligence and Information Systems
• /
• 제11권1호
• /
• pp.169-189
• /
• 2005

In order to derive a better classifier with a limited number of training examples, active teaming alternately repeats the querying stage fur category labeling and the subsequent learning stage fur rebuilding the calssifier with the newly expanded training set. To relieve the user from the burden of labeling, especially in an on-line environment, it is important to minimize the number of querying steps as well as the total number of query examples. We can derive a good classifier in a small number of querying steps by using only a small number of examples if we can select multiple of diverse, representative, and ambiguous examples to present to the user at each querying step. In this paper, we propose a cluster-based batch query selection method which can select diverse, representative, and highly ambiguous examples for efficient active learning. Experiments with various text data sets have shown that our method can derive a better classifier than other methods which only take into account the ambiguity as the criterion to select multiple query examples.

• The KIPS Transactions:PartD
• /
• 제10D권6호
• /
• pp.927-934
• /
• 2003

Database query optimates the selectivety of a query to find the most efficient access plan. Multi-dimensional selectivity estimation technique is required for a query with multiple attributes because the attributes are not independent each other. Histogram is practically used in most commercial database products because it approximates data distributions with small overhead and small error rates. However, histogram is inadequate for a query with multiple attributes because it incurs high storage overhead and high error rates. In this paper, we propose a novel method for multi-dimentional selectivity estimation. Compressed information from a large number of small-sized histogram buckets is maintained using the discrete cosine transform. This enables low error rates and low storage overheads even in high dimensions. Extensive experimental results show adventages of the proposed approach.

• Journal of KIISE:Databases
• /
• 제36권1호
• /
• pp.30-43
• /
• 2009

Broadcast in the wireless environment has drawn much attention because it is capable of sending data to clients regardless of the number of clients. Most previous researches have aimed at obtaining an independent data item in a minimum time. But, they have not been researched on simultaneously receiving dependent data items in a query. In addition, these papers have only researched allocation problem that have not been came out data items in a query in same time and different channels. The access probability of each data item based on query request probability have not been reflected. This paper proposes a new method of allocating data items and simultaneously minimizing average response time required in receiving all the dependent data items in a query. Our performance analysis shows that our proposed method gives better average response time over the existing methods.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 대한산업공학회/한국경영과학회 1991년도 춘계공동학술대회 발표논문 및 초록집; 전북대학교, 전주; 26-27 Apr. 1991
• /
• pp.309-310
• /
• 1991

• The KIPS Transactions:PartD
• /
• 제13D권1호
• /
• pp.11-22
• /
• 2006

As we are to deal with more and more XML documents, research on storing and managing XML documents in databases are actively conducted. Employing RDBMS or ORDBMS as a repository of XML documents is currently regarded as most practical. The query results out of XML documents stored in databases could be cached for query performance though the cost of cache consistency against the update of the underlying data is incurred. In this paper, we assume that an ORDBMS is used as a repository for the XML query cache as well as its underlying XML documents, and that XML query cache is refreshed in a deferred way with the update log. When the same XML document was updated multiple times, the deferred refresh of the XML query cache may Bet inefficient. We propose an algorithm that removes or filters such duplicate updates. Based on that, the optimal SQL statements that are to be executed for XML query cache consistency are generated. Through experiments, we show the efficiency of our proposed deferred refresh of XML query cache.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제12권3호
• /
• pp.1168-1188
• /
• 2018

Social Network Aggregators are used to maintain and manage manifold accounts over multiple online social networks. Displaying the Activity feed for each social network on a common dashboard has been the status quo of social aggregators for long, however retrieving the desired data from various social networks is a major concern. A user inputs the query desiring the specific outcome from the social networks. Since the intention of the query is solely known by user, therefore the output of the query may not be as per user's expectation unless the system considers 'user-centric' factors. Moreover, the quality of solution depends on these user-centric factors, the user inclination and the nature of the network as well. Thus, there is a need for a system that understands the user's intent serving structured objects. Further, choosing the best execution and optimal ranking functions is also a high priority concern. The current work finds motivation from the above requirements and thus proposes the design of a query processing system to retrieve information from social network that extracts user's intent from various social networks. For further improvements in the research the machine learning techniques are incorporated such as Latent Dirichlet Algorithm (LDA) and Ranking Algorithm to improve the query results and fetch the information using data mining techniques.The proposed framework uniquely contributes a user-centric query retrieval model based on natural language and it is worth mentioning that the proposed framework is efficient when compared on temporal metrics. The proposed Query Processing System to Retrieve Information from Social Network (QPSSN) will increase the discoverability of the user, helps the businesses to collaboratively execute promotions, determine new networks and people. It is an innovative approach to investigate the new aspects of social network. The proposed model offers a significant breakthrough scoring up to precision and recall respectively.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• 제32권4A호
• /
• pp.358-364
• /
• 2007

RFID, Radio Frequency Identification, technology is a contactless automatic identification technology using radio frequency. For this RFID technology to be widely spread, the problem of multiple tag identification, which a reader identifies a multiple number of tags in a very short time, has to be solved. Up to the present, many anti-collision algorithms have been developed in order to solve this problem, and those can be largely divided into ALOHA based algorithm and tree based algorithm. In this paper, two new anti-collision algorithms combining the characteristics of these two categories are presented. And the performances of the two algorithms are compared and evaluated in comparison with those of typical anti-collision algorithms: 18000-6 Type A, Type B, Type C, and query tree algorithm.

• The KIPS Transactions:PartB
• /
• 제12B권2호
• /
• pp.191-202
• /
• 2005

The Semantic Web Services is a next-generation Web technology that supports Web services, based on the semantic Web technologies. Until now, the researches on semantic Web services may be foiled on the semantic Web document management and the inference engine to efficiently process the semantic Queries. However, in order to realize the principle semantic Web environment it is necessary to provide a semantic query interface though which users and/or agents can efficiently request semantic information. In this regard, we propose the Semantic Query Adapter(SQA) to provide a high query transparency with users, especially when querying about a complex semantic information. We first design the procedural user query interface based on a graphic view, by analyzing DAML-S Profile documents. And then, we builds a module which a user input query transforms its corresponding RDQL. We also propose the multiple semantic query generating procedure as a new method to solve the disjunctive query problem of the RDQL primitive.

• Database Research
• /
• 제34권3호
• /
• pp.69-85
• /
• 2018

Many researches proposed federated query engines to perform query on several homogeneous or heterogeneous datasets simultaneously that significantly improve the quality of query results. The existing techniques allow querying only over a few heterogeneous datasets considering the static binding using the non-standard query. However, we observe that a simultaneous system considering the integration of heterogeneous metadata standards can offer better opportunity to generalize the query over any homogeneous and heterogeneous datasets. In this paper, we propose a transparent federated engine (DRAZ) to query over multiple data sources using SPARQL. In our system, we first develop the ontology for a non-RDF metadata standard based on the metadata kernel dictionary elements, which are standardized by the metadata provider. For a given SPARQL query, we translate any triple pattern into an API call to access the dataset of corresponding non-RDF metadata standard. We convert the results of every API call to N-triples and summarize the final results considering all triple patterns. We evaluated our proposed DRAZ using modified Fedbench benchmark queries over heterogeneous metadata standards, such as DCAT and DOI. We observed that DRAZ can achieve 70 to 100 percent correctness of the results despite the unavailability of the JOIN operations.

• Journal of information and communication convergence engineering
• /
• 제9권3호
• /
• pp.260-265
• /
• 2011

In RFID System, when multiple tags respond simultaneously, a collision can occur. A method that solves this collision is referred to anti-collision algorithm. In 13.56MHz RFID system, STAC protocol is defined as an anti-collision algorithm for multiple tag reading. In STAC protocol, there is no differentiation between the collided tags and others in the identification process. Therefore, tags may never be successfully identified because its responses may always collide with others. This situation may cause the tag starvation problem. This paper proposes a fair identification scheme for STAC protocol. In the proposed scheme, if the number of collided slots is large during a query round, the reader broadcasts a CollisionRound command to begin a collision round. During the collision round, the reader identifies only tags that are experienced collision during the previous query round.