• Journal of Information Technology Applications and Management
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• 제11권1호
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• pp.53-67
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• 2004

We propose an advanced transaction scheduling protocol to improve the concurrency and to guarantee the mobility for the mobile database management systems. Mobility, portability, and wireless link In mobile computing environment can cause certain drawbacks, and thus it is more difficult to solve the concurrency control problems. However, a locking scheme should be used to guarantee the data consistency and to prevent the data conflicts. It is well known that data consistency is guaranteed by standard transaction scheduling schemes like two-phase locking (2PL). It has two of operation, lock and unlock. But 2PL does not give solution for mobile system. Altruistic Locking (AL) and classifying transactions, we adapt, can give solution for the previous problems. AL, as an advanced protocol, has attempted to reduce delay effects associated with lock release moment by the use of donation. In this paper, we extend those approaches and classify the transactions to reduce delay effects of short-lived transaction caused by long-lived transaction. In addition, we show efficient solution for the case of disconnection occurrence. Our protocol, namely, Mobile Altruistic Locking (MAL) is shown to be efficiently used in order to reduce delay effects and to guarantee database consistency in a state of the slippery connection in mobile database systems.

• 무역상무연구
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• 제29권
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• pp.143-172
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• 2006

This study focuses on the risk management of "Digital Goods" appeared with the progress of information technology(IT) in international transaction. As a result of that digital goods have a lot of uncertainty between the general goods or service which have been deal with object of international transaction broadly because digital goods hold uniqueness. In this study, the author give a definition of "Digital Goods" and make an examination of uniqueness of that in international transaction. Next, six risks are defined base on risk theory and risk analysis matrix applying risk mapping model is made. Conclusionally, risk transfer as insurance is adequate to manage business risk, security risk, credit risk and legal risk. Meanwhile, risk avoidance is adequate to manage reputation risk and market risk. But, this study have following three limits. Firstly, concerning definition of the risk, real case is not applied owing to lack of transaction data. Secondly, measuring of the risk is not based on absolute data but relative data. Lastly, suggesting way of risk management is not concrete and practical to international trader of digital goods.

• 한국멀티미디어학회논문지
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• 제12권1호
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• pp.41-49
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• 2009

오늘날 대부분의 스마트카드는 자바카드 플랫폼을 채택한 자바카드가 표준안으로 자리매김 하고 있다. 자바카드는 전원이 차단되면 작업 중이던 데이터가 손실되는 문제점을 가지고 있다. 데이터 손실의 해결책으로 트랜잭션 개념이 사용되지만, 한 번에 하나의 트랜잭션 처리만을 허용하므로, 트랜잭션이 필요한 작업들은 이전에 작업 중인 트랜잭션이 끝날 때까지 대기해야 하고, 이는 자바 카드의 성능을 저하시키는 요인이다. 본 논문에서는 자바 카드의 수행 성능을 향상시키기 위한 방안으로 다중 트랜잭션 버퍼에서 트랜잭션을 수행할 수 있도록 이중 잠금 규칙을 규정하고, 이 규칙에 따라 트랜잭션을 처리함으로써 트랜잭션 처리 성능을 개선시키고자 한다. 이러한 연구 결과를 통해 데이터의 안전성을 놀이고 트랜잭션이 필요한 데이터의 대기 시간을 줄이고 자바 카드의 수행 속도를 증가 시킬 수 있다.

• 한국전자통신학회논문지
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• 제7권4호
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• pp.873-879
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• 2012

최근에 클라우드 컴퓨팅 패러다임은 다양한 응용에서 받아들여지고 있다. 클라우드 환경의 데이터 관리 시스템은 대용량의 데이터와 확장성을 지원하는 능력이 요구된다. 대용량의 데이터를 다루기 위해 일관성과 트랜잭션의 제약을 완화하는 것이 필요하고, 확장성을 지원하기 위해 구성 요소의 가감을 허용해야 한다. 이 논문에서는 클라우드 환경에서 트랜잭션을 처리할 때 필요한 시스템 모델과 확장가능한 모듈 관리 알고리즘에 대하여 제안한다. 시스템 모델은 트랜잭션 관리 모듈과 데이터 관리 모듈로 구성된다. 모듈 관리 알고리즘은 불필요한 재분배가 발생하지 않고, 기존 모듈의 부하를 덜어줄 수 있다. 성능 분석 결과, 모듈의 확장으로 응답 시간을 향상시키고 트랜잭션 철회율을 감소시킬 수 있음을 알 수 있었다.

• 한국통신학회논문지
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• 제31권4B호
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• pp.285-290
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• 2006

엔터프라이즈 애플리케이션 개발을 위한 분산 아키텍처를 개발할 때는 여러 고려 사항 중에서 계층(tier)의 응집력(cohesion)을 높이고 계층간 연결 결합력(coupling)을 낮추기 위해 페이지 작성자와 소프트웨어 개발자의 역할을 명확히 분리하는 것과 비즈니스 로직의 단위가 되는 엔터티(entity)를 정의하고 데이터베이스 연결과 트랜잭션 처리에 엔터티의 사용 및 역할에 대해 정의하는 것이 우선적으로 필요하다. 이 논문에서는 DONSL(Data Server of Non SQL query) 아키텍처를 제시하여 이러한 문제점을 해결하고자 한다. 이 아키텍처는 웹 티어 오브젝트 모델링 방법을 사용하며 계층(tier)간의 결합도를 낮추고, 데이터베이스 연결에 반드시 사용되는 DAO(Data Access Object)와 엔터티를 효과적으로 분리하여 이러한 문제점을 해결 한다. 핵심 내용으로 DAO에서 엔터티 객체를 제거하는 방안을 통해 DAO 개발을 용이하게 하는 방법과 SQL 질의 자동 생성을 통해 트랜잭션 처리 자동화 방법, 그리고 트랜잭션 처리시 AET(Automated Executed Transaction)와 MET(Manual Executed Transaction)를 효율적으로 운용하는 방법에 대해 제시하고 시스템을 구현하였다.

• 농촌의학ㆍ지역보건
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• 제49권1호
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• pp.59-70
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• 2024

Objectives: This research analyzed and compared housing transaction prices and depression rates according to housing types before and after the COVID-19 pandemic. Methods: Data on housing transaction prices and depression rates from 2018 to 2022 in 25 districts of Seoul, South Korea, were utilized. Dummy variables were employed to account for potential confounders influencing the relationship between the variables. Statistical analysis was conducted using R, and the relationship between depression rates and housing transaction prices was examined through Ordinary Least Squares (OLS) and panel data regression analysis. Results: The results of OLS and one-way random effects models indicated a significant relationship between apartment (p<.05) and officetel (p<.001) transaction prices and depression. However, detached/semi-detached and row/townhouse transaction prices did not exhibit a significant relationship with depression. Conclusion: It was observed that as apartment and officetel transaction prices increased in Seoul before and after the COVID-19 pandemic, depression rates also increased. Considering that changes in housing prices by housing type in South Korea may impact the mental health of local residents, it is deemed necessary to consider healthy housing and housing prices as comprehensive determinants of mental health.

• 지식경영연구
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• 제21권1호
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• pp.117-136
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• 2020

In the studies for the recommender systems which solve the information overload problem of users, the use of transactional data has been continuously tried. Especially, because the firms can easily obtain transactional data along with the development of IoT technologies, transaction-based recommender systems are recently used in various areas. However, the use of transactional data has limitations that it is hard to reflect domain knowledge and they do not directly show user preferences for individual items. Therefore, in this study, we propose a method applying the word embedding in the transaction-based recommender system to reflect preference differences among users and domain knowledge. Our approach is based on SAR, which shows high performance in the recommender systems, and we improved its components by using FastText, one of the word embedding techniques. Experimental results show that the reflection of domain knowledge and preference difference has a significant effect on the performance of recommender systems. Therefore, we expect our study to contribute to the improvement of the transaction-based recommender systems and to suggest the expansion of data used in the recommender system.

• 한국경영과학회지
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• 제27권4호
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• pp.29-39
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• 2002

The transaction tables of the existing association algorithms have two column attributes : It is composed of transaction identifier (Transaction_id) and an item identifier (item). In this kind of structure, as the volume of data becomes larger, the performance for the SQL query statements came applicable decreases. Therefore, we propose advanced association rules algorithm of n-items which can transact multiple items (Transaction_id, Item 1, Item 2…, Item n). In this structure, performance hours can be contracted more than the single item structures, because count can be computed by query of the input transaction tables. Our experimental results indicate that performance of the n items structure is up to 2 times better than the single item. As a result of this paper, the proposed algorithm can be applied to internet shopping, searching engine and etc.

• 한국국방경영분석학회지
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• 제22권1호
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• pp.81-96
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• 1996

In a relational database environment, partitioning of data is directly concerned with the amount of data that needs to be required in a query or transaction. In this paper, we consider non-overlapping, vertical partitioning. Vertical partitioning algorithm in this paper is composed of two phases. In phase 1, we cluster the attributes with zero-one integer program that maximize affinity among attributes. The result of phase 1 is called 'Initial Fragments'. In phase 2, we modify Initial Fragments that is not directly considered by cost factors, making use of a transaction-based partitioning method. A transaction-based partitioning method is partitioning attributes according to a set of transactions. In this phase we select logical accesses which needs to be required in a transaction as comparison criteria. In phase 2, proposed algorithm consider only small number of modification of Initial Fragments in phase 1. This algorithm is so insensible to number of transactions and of attributes that it can applied to relatively large problems easily.

• 무역학회지
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• 제46권2호
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• pp.93-106
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• 2021

This study analyzes trade communication methods by comparing and analyzing payment methods and procedures of L/C and BPO transactions. As a result of the study, BPO transaction is validated based on the combination results of the confirmed baseline and data set unlike the L/C transaction. Therefore, BPO is superior to L/C transaction in that there is no confrontation between the parties over the matching results. And it can proceed with certain transaction that is paid first and proved later. In addition, the process of accepting data mismatches results in a confirmation of the payment commitment considering the intention of the importer. This allows flexible disposition of documents in response to the post payment situation as long as the documents are held by the exporter, which can be said to be superior to the L/C transaction.