• Journal of the Korea Computer Industry Society
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• v.3 no.7
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• pp.921-926
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• 2002

B+-Tree is the most popular indexing method in DBMS to manage large size data in more efficiency. However the existing B+-Tree has shortcomings in there is overhead on DISK/IO when the first time of constructing DB or of making Index, and it lessens the concurrency if there are frequent delete operations so that the index structure also should be changed frequently. To solve these problems almost DBMS is using batch construction method and lazy deletion method. But to apply B+-Tree, which is using batch construction method and lazy deletion method, into DBMS the technique for controlling and recovering concurrency is necessary, but its researching is still unsatisfactory so that there is a problem on applying it into actual systems. On this paper I suggest the technique for controlling and recovering concurrency how to implement the batch construction method and the lazy deletion method in actual DBMS. Through the suggested technique there is no cascade rollback by using Pending list, it enhances the concurrency by enabling insertion and deletion for base table on every reconstruction, and it shortens transaction response time for user by using system queue which makes the batch constructing operation is processed not in user's transaction level but in system transaction level.

• The Journal of the Korea Contents Association
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• v.13 no.2
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• pp.498-504
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• 2013

Recently, the frequency of typhoons have increased due to the effects of climate change. As a result, in mountain streams, it has caused streamflow increase upstream and frequent water surface elevation downstream. This study analyzed the effects of the heavy rainfalls caused by Typhoon Sanba, which had a direct impact on Korea between September 17 and 18, on the water level variations downstream in mountainous streams. In addition, the drainage basin of Samcheok Oship stream was chosen as the object of this study. This study analyzed the flood level by applying HEC-RAS model. The observed water level measured in 2012 and the water level simulated by HEC-RAS model showed similar results. In addition, the simulation results showed the maximum flood level was 5.32m the mean flow velocity was 2.33m/sec and the maximum channel water depth was 7.51m. The analysis showed that the heavy rainfalls caused by Typhoon Sanba had an impact on the water surface elevation in Oship stream. The final results from this study will give a reasonable and important data to perform the Design of Hydraulic Structure.

• Journal of KIISE:Software and Applications
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• v.26 no.10
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• pp.1247-1259
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• 1999

본 논문에서는 한국어 문장형성원리를 간결하게 제시할 수 있도록 X-바 이론의 중심어 개념을 도입한 한국어 자질기반 문법을 제안한다. 제안하는 문법은 어절에 관계없이 나타나는 한국어의 문법현상을 명확히 설명할 수 있도록 어절 대신 형태소를 기본단위로 한다. 그리고, 한국어의 구문범주가 지닌 의미정보와 기능정보를 자질을 이용하여 독립적으로 표현하며, 구문범주간의 결합관계를 바탕으로 하는 자질연산을 수행하여 문장을 분석한다. 또한, 한국어의 부분자유어순과 생략현상에 대해 견고하게 분석할 수 있도록 자질연산을 이진결합중심의 CNF(Chomsky Normal Form)로 제한한다. 이렇게 구성된 한국어 자질기반 문법은 규칙을 직관적이고도 간단하게 기술하며, 한국어의 다양한 문장들을 견고하게 분석한다. SERI Test Suites 97과 신문기사에서 746문장을 추출하여 실험한 결과 94%~99%의 적용율을 보였다.Abstract In this paper, we propose a Korean feature-based grammar(KFG) which adopts the X-bar theoretic notion of headedness for a precise representation of Korean syntactic structure. In order to explain various language phenomena in a given sentence, we use not the word but the morpheme as a constituent unit of KFG. We use features manifesting both the syntactic information and the semantic information of Korean syntactic categories, and feature operations based on the association relationship between two categories. In addition, we restrict feature operations to CNF(Chomsky Normal Form) binary form, which provides a robust representation for properties in Korean such as the frequent ellipsis and the partial free-order. The KFG is intuitive, simple, and versatile in representing most Korean sentences. The experimental result shows 94%~99% coverage on 746 sentences extracted from SERI Test Suites 97 and newspaper sentences.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6458-6465
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• 2015

Frequent change of mobile applications has become a burden to management of mobile services. Therefore, the development of mobile Web services, which the central management is easy, has increased. Tools which developers, as well as general users can easily develop, have been developed for mobile Web services. However, researches of standardized metamodel for implementing mobile Web service dynamically by general users is the inadequate situation. In this paper, we propose a dynamic metamodel for developing mobile Web services. The dynamic metamodel consists of a mobile Web pages, mobile Web page instance and dynamic connection using XDPL structure. we study a connection metamodel for condition connection, split connection and join connection, and combile entire metamodel, finally. Also, we carry out a case study in order to verify the suitability of metamodel by based on XPDL.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.7A
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• pp.569-580
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• 2012

In this paper, an enhanced initial ranging algorithm for large-cell coverage fixed wireless communication system is proposed. In typical wireless communication system such as WiBro, because a round-trip delay between a transmitter and a receiver is within one OFDM (Orthogonal Frequency Division Multiplexing) symbol duration, a frequency-domain differential correlation method is generally used. However, the conventional method cannot be applied due to an increase of a maximum time delay in large-cell system. In case of an accumulative differential method, estimation errors can occur because of frequent sign transitions. In this paper, therefore, we propose an algorithm which can estimate a total timing offset in a ranging channel structure for 15 km cell. The proposed method can improve performance by sign comparison based sign error correction rule between the estimated values and using a weighting scheme based on channel correlation, the number of accumulations, and the noise reduction effect in normalization process. Also, it can estimate the integer timing offset of symbol duration by comparing peak-powers after compensating for the fractional timing offset of symbol duration.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3A
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• pp.296-305
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• 2010

Secondary users should sense the licensed spectrum bands in order to protect the primary users from interference. However, periodic and frequent sensing for immediate detection of primary users usually gives rise to much sensing overhead, and thus will quickly drain the battery as well as deteriorate the performance of a secondary user. To overcome such problems, we focus on the method reducing sensing overhead of each secondary user and propose a distributed fair sensing scheme that the multiple users within a certain area, so-called sensing zone, sense the spectrum bands in a fairly distributed manner and share the results among the users within respective sensing zone. The design of the frame structure for the proposal is also demonstrated while considering the sensing requirements for protecting primary users. The performance results by numerical analyses and computer simulations show that our proposed sensing scheme significantly reduces the sensing overhead of each user compared to the conventional sensing scheme and also satisfies the given sensing requirements for primary user protection.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.3
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• pp.316-320
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• 2008

Data dissemination schemes for wireless sensor networks, where sinks and event targets might be mobile, has been one of the active research fields. For doing that, stationary nodes gathered data on behalf of mobile sinks and the relayed data in previous studies. their schemes, however, lead to frequent query flooding and report congestion problems over sink moving. We propose a data dissemination protocol to solve both the query flooding and the report congestion problem. Our scheme improves the two shortcomings through sink location management. Finally, we prove effectiveness of our protocol through computer simulations.

• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.662-667
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• 2020

Epidermal growth factor receptor (EGFR) mutations are not only genetic markers for diagnosis but also biomarkers of clinical-response against tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC). Among the EGFR mutations, the in-frame deletion mutation in EGFR exon 19 kinase domain (EGFR exon 19-del) is the most frequent mutation, accounting for about 45% of EGFR mutations in NSCLCs. Development of sensitive method for detecting the EGFR mutation is highly required to make a better screening for drug-response in the treatment of NSCLC patients. Here, we developed a fluorometric tandem gene amplification assay for sensitive detection of low-abundance EGFR exon 19-del mutant genomic DNA. The method consists of pre-amplification with PCR, thermal cycling of ligation by Taq ligase, and subsequent rolling circle amplification (RCA). PCR-amplified DNA from genomic DNA samples was used as splint DNA to conjugate both ends of linear padlock DNA, generating circular padlock DNA template for RCA. Long stretches of ssDNA harboring multiple copies of G-quadruplex structure was generated in RCA and detected by thioflavin T (ThT) fluorescence, which is specifically intercalated into the G-quadruplex, emitting strong fluorescence. Sensitivity of tandem gene amplification assay for detection of the EGFR exon 19-del from gDNA was as low as 3.6 pg, and mutant gDNA present in the pooled normal plasma was readily detected as low as 1% fraction. Hence, fluorometric detection of low-abundance EGFR exon 19 deletion mutation using tandem gene amplification may be applicable to clinical diagnosis of NSCLC patients with appropriate TKI treatment.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.4
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• pp.33-42
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• 2000

This study is carried out to investigate plant community structure, actual vegetation map and flora for examining the relationship between naturally introduced vegetation and surrounding vegetation in Hamtae coal-mined spoil lands. According to the analysis of vegetation, surrounding vegetation was divided into five plant community groups : Pinus koraiensis community, Pinus densiflora - Quercus mongolica community, Q. mongolica - Deciduous broadleaved trees community, Betula schmidtii - B. davurica community, Larix leptolepis community. Robinia pseudo-acacia, which had been planted, was dominant species in coal-mined spoil lands. Young trees, which were naturally introduced, such as B. schmidtii, B. davurica etc., partially appeared with the high density($15{\sim}19ea/100m^2$) in coal-mined spoil lands. The flora of this area was listed as 54 taxa; 22 families, 42 genus, 50 species, 3 varieties and 1 forma. Especially Spodiopogon sibiricus, Miscanthus sinensis, Arundinella hirta, Artemisia capillaris, Artemisia iwayomogi and Youngia denticulata appeared with the high frequency. It is estimated that the proper way for harmonious and effective revegetation is to target B. schmidtii - B. davurica communities and to seed B. schmidtii - B. davurica mixing highly frequent herbaceous species.

• Smart Media Journal
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• v.1 no.2
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• pp.12-22
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• 2012

Today we are witnessing an increasingly widespread use of cameras in our lives for video surveillance, robot vision, and mobile phones. This has led to a renewed interest in computer vision in general and an on-going boom in human activity recognition in particular. Although not particularly fancy per se, human gait is inarguably the most common and frequent action. Early on this decade there has been a passing interest in human gait recognition, but it soon declined before we came up with a systematic analysis and understanding of walking motion. This paper presents a set of DBN-based models for the analysis of human gait in sequence of increasing complexity and modeling power. The discussion centers around HMM-based statistical methods capable of modeling the variability and incompleteness of input video signals. Finally a novel idea of extending the discrete state Markov chain with a continuous density function is proposed in order to better characterize the gait direction. The proposed modeling framework allows us to recognize pedestrian up to 91.67% and to elegantly decode out two independent gait components of direction and posture through a sequence of experiments.