• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.4
• /
• pp.848-854
• /
• 2015

There are a lot of encryption methods to secure database proposed recently. Those encryption methods can protect the sensitive data of users effectively, but it deteriorates the search performance of database query. In this paper, we proposed the selective element encryption method in order to complement those drawbacks. In addition, we compared the performance of the proposed method with that of tuple level encryption method using the various queries. As a result, we found that the proposed method, which use the selective element encryption with bloom filter as a index, has better performance than the other encryption method.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.9 no.7
• /
• pp.1555-1560
• /
• 2005

The presentation of query results is usually made with an external tool or a report generator but, because the methods of preparing and storing presentations have not been standardized, there are many difficulties for other applications to use query results. Thus, it is necessary for a multimedia data query language to define presentation in a standardized method. In this paper we designed extented SQL is based on SMIL 2.0, which support the proposed presentation model effectively. Furthermore this study proposed methods of using query results in various multimedia applications.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.3C
• /
• pp.249-255
• /
• 2007

In general, a large amount of the memory accesses are required for the CAVLC decoding in H.264/AVC. It is a serious problem for the applications such as a DMB and videophone services because the considerable power is consumed for accessing the memory. In order to solve this problem, we propose an efficient decoding method for the coeff-token which is one of the syntax elements of CAVLC. In this paper, the variable length code table is re-designed with the new codewords which are defined by investigating the architecture of the conventional codeword for the coeff_token element. A new coeff_token decoding method is developed based on the suggested table. The simulation results show that the proposed algorithm achieves an approximately 85% memory access saving without video-quality degradation, compared to the conventional CAVLC decoding.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.4
• /
• pp.720-726
• /
• 2009

There are coexisting various kinds of data in the large scale database system, the maintenance problem of freshness of data is emerging important issue that provide correctness and usefulness information to users. Most solution of this problem depends on how execute effectively required refreshing query within timely time. In this paper, we propose the refreshing scheduling algorithm to retain the freshness of data and fairness of starvation of requested refresh queries. Our algorithm recompute a rate of goal refreshing a every period to assign execution time of requested refreshing query so that we can keep the freshness and fairness of data by using proposed algorithm. We implement the web sites to showing the results of refreshing process of dynamic and semi-dynamic and static data.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.6C
• /
• pp.561-569
• /
• 2003

In this paper, for my linear orthogonal space-time block including the orthogonal space-time codes introduced by Alamouti［1］, Tarokh［14］, and Xia［11］, the exact expression for the pairwise error probability in the slow Rayleigh fading channel is derived in terms of the message symbol distance between two message vectors rather than the codeword symbol distance between two transmitted codeword matrices. Using the one-dimensional component symbol error probability, the exact closed form expressions for the symbol error probability of linear orthogonal space-time codes are derived for QPSK, 16-QAM, 64-QAM, and 256-QAM.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.05a
• /
• pp.169-170
• /
• 2017

In this paper, we analyze contents of formal and non - standardized data to understand what factors affect the ratings of drama. The formalized data collection collected 19 items from the four areas of drama information, person information, broadcasting information, and audience rating information of each broadcasting company. In order to collect unstructured data, crawling techniques were used to collect bulletin boards, pre - broadcast blogs and post - broadcast blogs for each drama. From the collected data, it was found that the differences according to broadcasting time, the start time, genre, and day of broadcasting were similar among broadcasting companies.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.3A
• /
• pp.173-179
• /
• 2002

In this paper, we suggest more precise performance analysis method of turbo interleavers based on two criteria; performance bounds like Union Bound and weight frequency of codewords. In order to present our new method, we employ block pseudo random, and so-called prime interleavers in compliance of 3GPP standard, respectively, We also applied this method to S-random interleavers that have different window size, S. 3GPP complied turbo encoder, decoder, and AWGN channel are implemented by using MATLAB for our performance analysis. According to our analysis, both criteria should be taken into account coincidently to predict the performance of newly designed interleavers.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.10C
• /
• pp.1363-1369
• /
• 2004

LDPC(Low Density Parity Check) codes are described by bipartite graphs with bit nodes and parity-check nodes. Tanner derived minimum distance bounds of the regular LDPC code in terms of the eigenvalues of the associated adjacency matrix. In this paper we generalize the Tanner's results. We derive minimum distance bounds applicable to both regular and blockwise-irregular LDPC codes. The first bound considers the relation between bit nodes in a minimum-weight codeword, and the second one considers the connectivity between parity nodes adjacent to a minimum-weight codeword. The derived bounds make it possible to describe the distance property of the code in terms of the eigenvalues of the associated matrix.

• Journal of Korean language education
• /
• v.29 no.2
• /
• pp.1-23
• /
• 2018

This study aims to analyze words and phrases which are frequently used in newsletters from Korean elementary schools. In order to achieve this goal, high frequent words from school newsletters were selected and classified into content and function words, and the domains of the words were looked up. For this study 1,000 school newsletters were collected in the areas of Busan, Ulsan and Gyeongnam. In terms of parts of speech, nouns, especially common nouns, most frequently appeared in the school newsletters followed by verbs and adjectives. This result shows that for immigrant women who have basic knowledge on Korean language, it is useful to give translated words to get the message of school letters. Furthermore, school related terms such as facilities, regulations and activities of school and Chinese-based vocabularies are found in school newsletters. In case of verbs, the words which contain the meaning of requests and suggestions are used the most. Adjectives which are related to positive value and evaluation, and describing weather and season is frequently used as well.

• Annual Conference on Human and Language Technology
• /
• 2019.10a
• /
• pp.276-279
• /
• 2019

의존 구문 분석은 문장을 구성하는 성분들 간의 의존 관계를 분석하고 문장의 구조적 정보를 얻기 위한 기술이다. 의미역 결정은 문장에서 서술어에 해당하는 어절을 찾고 해당 서술어의 논항들을 찾는 자연어 처리의 한 분야이다. 두 기술은 서로 밀접한 상관관계가 존재하며 기존 연구들은 이 상관관계를 이용하기 위해 의존 구문 분석의 결과를 의미역 결정의 자질로써 사용한다. 그러나 이런 방법은 의미역 결정 모델의 오류가 의존 구문 분석에 역전파 되지 않으므로 두 기술의 상관관계를 효과적으로 사용한다고 보기 어렵다. 본 논문은 포인터 네트워크 기반의 의존 구문 분석 모델과 병렬화 순환 신경망 기반의 의미역 결정 모델을 멀티 태스크 방식으로 학습시키는 통합 모델을 제안한다. 제안 모델은 의존 구문 분석 및 의미역 결정 말뭉치인 UProbBank를 실험에 사용하여 의존 구문 분석에서 UAS 0.9327, 의미역 결정에서 PIC F1 0.9952, AIC F1 0.7312의 성능 보였다.