• Communications for Statistical Applications and Methods
• /
• v.16 no.1
• /
• pp.21-29
• /
• 2009

Engle and Russell (1998) proposed the ACD(Autoregressive Conditional Duration) model to explain the relationship between the prices and the duration times of the stocks. In this paper, we first introduce the various types of the ACD models such as the linear ACD, log ACD and Box-Cox ACD models and we evaluate the performance of the models for analysing the transaction data of the stocks in Korea.

• Journal of Information Science Theory and Practice
• /
• v.10 no.1
• /
• pp.73-88
• /
• 2022

This exploratory study aims to understand the potential of log data analysis and expand its utilization in user research methods. Transaction log data are records of electronic interactions that have occurred between users and web services, reflecting information-seeking behavior in the context of digital libraries where users interact with the service system during the search for information. Two ways were used to analyze South Korea's National Digital Science Library (NDSL) log data for three days, including 150,000 data: a log pattern analysis, and log context analysis using statistics. First, a pattern-based analysis examined the general paths of usage by logged and unlogged users. The correlation between paths was analyzed through a χ² analysis. The subsequent log context analysis assessed 30 identified users' data using basic statistics and visualized the individual user information-seeking behavior while accessing NDSL. The visualization shows included 30 diverse paths for 30 cases. Log analysis provided insight into general and individual user information-seeking behavior. The results of log analysis can enhance the understanding of user actions. Therefore, it can be utilized as the basic data to improve the design of services and systems in the digital library to meet users' needs.

• Journal of the Korean Society for information Management
• /
• v.17 no.2
• /
• pp.139-153
• /
• 2000

This article focuses on a transaction log analysis of the DISCOVER online catalog user interface at Duksung Women's University Library. The results show that the most preferred access point is the title field with rate of 59.2%. The least used access point is the author field with rate of 11.6%. Keyword searching covers only about 16% of all access points used. General failure rate of searching is 13.9% with the highest failure rate of 19.8% in the subject field and the lowest failure rate of 10.9% in author field.

• Journal of KIISE:Databases
• /
• v.27 no.1
• /
• pp.129-140
• /
• 2000

We propose the ARIES/RL which extends the with 're-logging' technique to manage the limited online 1og space efficiently even though 1ong-duration transactions exist. Re-logging isa technique that log records used in transaction rollback and restart recovery are copied forward in the log whenever the online log is not sufficient for keeping logs of on-going transactions It does not hurt the advantages of ARIES. Moreover, it handles log space efficiently in executing long-duration transactions. We also present the evaluation result of ARIES/RL and show that ARIES/RL handles online log efficiently.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.6 no.2
• /
• pp.107-118
• /
• 2010

This paper proposes a digital forensic method to a file creation transaction using a journal file($LogFile) on NTFS File System. The journal file contains lots of information which can help recovering the file system when system failure happens, so knowledge of the structure is very helpful for a forensic analysis. The structure of the journal file, however, is not officially opened. We find out the journal file structure with analyzing the structure of log records by using reverse engineering. We show the digital forensic procedure extracting information from the log records of a sample file created on a NTFS volume. The related log records are as follows: bitmap and segment allocation information of MFT entry, index entry allocation information, resident value update information($FILE_NAME, $STANDARD_INFORMATION, and INDEX_ALLOCATION attribute etc.).

• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 2003.11a
• /
• pp.621-626
• /
• 2003

Mining association rules in web log files can be divided into two steps: 1) discovering frequent item sets in web data; 2) extracting association rules from the frequent item sets found in the previous step. This paper suggests an algorithm for finding frequent item sets efficiently The essence of the proposed algorithm is to transform transaction data files into matrix format. Our experimental results show that the suggested algorithm outperforms the Apriori algorithm, which is widely used to discover frequent item sets, in terms of scan frequency and execution time.

• The Journal of the Korea Contents Association
• /
• v.19 no.5
• /
• pp.187-193
• /
• 2019

Key-value storage engines are an essential component of growing demand in many computing environments, including social networks, online e-commerce, and cloud services. Recent key-value storage engines offer many features such as transaction, versioning, and replication. In a key-value storage engine, transaction processing provides atomicity through Write-Ahead-Logging (WAL), and a synchronous commit method for transaction processing flushes log data before the transaction completes. According to our observation, flushing log data to persistent storage is a performance bottleneck for key-value storage engines due to the significant overhead of fsync() calls despite the various optimizations of existing systems. In this article, we propose a group synchronization method to improve the performance of the key-value storage engine. We also design and implement a transaction scheduling method to perform other transactions while the system processes fsync() calls. The proposed method is an efficient way to reduce the number of frequent fsync() calls in the synchronous commit while supporting the same level of transaction provided by the existing system. We implement our scheme on the WiredTiger storage engine and our experimental results show that the proposed system improves the performance of key-value workloads over existing systems.

• The Transactions of the Korea Information Processing Society
• /
• v.7 no.6
• /
• pp.1753-1765
• /
• 2000

As the areas of computer application are expanded, real-time application environments that must process as many transactions as possible within their deadlines, such as a stock transaction systems, ATM switching systems etc, have been increased recently. The reason why the conventional database systems can't process soft real-time applications is the lack of prediction and poor performance on processing transaction's deadline. If transactions want to access data stored at the secondary storage, they can not satisfy requirements of real-time applications because of the disk delay time. This paper designs a main-memory database prototype systems to be suitable to real-time applications and then this system can produce rapid results without disk i/o as all of the information are loaded in main memory database. In thesis proposed the improved techniques with respect to logging, checkpointing, and recovering in our environment. In order to improve the performance of the system, a) the frequency of log analysis and redo processing is reduced by the proposed redo technique at system failure, b) database consistency is maintained by improved fuzzy checkpointing. The performance model is proposed which consists of two parts. The first part evaluates log processing time for recovery and compares with other research activities. The second part examines checkpointing behavior.

• Journal of the Korean Society for information Management
• /
• v.32 no.4
• /
• pp.289-305
• /
• 2015

This study aims to investigate information seeking behavior of Popshoes users. Transaction logs of Popshoes, a major Korean shopping search engine, were analyzed. These transaction logs were collected over 3 months period, from January 1 to March 31, 2015. The results of this study show that Popshoes users behave in a simple and passive way. In the total sessions, more users chose to browse a directory than typing and submitting a query. However, queries played a more crucial role in important decision makings such as search results clicks and product purchases than directory browsing. The results of this study can be implemented to the effective development of shopping search engines.

• Journal of Korea Multimedia Society
• /
• v.6 no.4
• /
• pp.707-713
• /
• 2003

Convenience and promptness of the internet have been not only making the electronic commerce grow rapidly in case of website, analyzing a navigation pattern of the users has been also making personalization and customization techniques develop rapidly for providing service accordant to individual interestingness. Web personalization and customization skill has been utilizing various methods, such as web log mining to use web log data and web mining to use the transaction of users etc, especially e-CRM analyzing a navigation pattern of the users. In this paper, We measure exact duration time of the users in web page and web site, compute weight about duration time each page, and propose a way to comprehend e-loyalty through the computed weight.