• ETRI Journal
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• 제38권6호
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• pp.1197-1206
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• 2016

Performing continuous skyline queries of dynamic data sets is now more challenging as the sizes of data sets increase and as they become more volatile due to the increase in dynamic updates. Although previous work proposed support for such queries, their efficiency was restricted to small data sets or uniformly distributed data sets. In a production database with many concurrent queries, the execution of continuous skyline queries impacts query performance due to update requirements to acquire exclusive locks, possibly blocking other query threads. Thus, the computational costs increase. In order to minimize computational requirements, we propose a method based on a multi-layer grid structure. First, relational data object, elements of an initial data set, are processed to obtain the corresponding multi-layer grid structure and the skyline influence regions over the data. Then, the dynamic data are processed only when they are identified within the skyline influence regions. Therefore, a large amount of computation can be pruned by adopting the proposed multi-layer grid structure. Using a variety of datasets, the performance evaluation confirms the efficiency of the proposed method.

• 대한조선학회논문집
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• 제55권3호
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• pp.243-251
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• 2018

In the shipyard, a lot of data is generated, stored, and managed during design, construction, and operation phases to build ships and offshore structures. However, it is difficult to handle such big data efficiently using existing data-handling technologies. As the big data technology is developed, the ship and offshore industries start to focus on the existing big data to find valuable information from it. In this paper, the material requirement estimation method of offshore structure piping materials using big data analysis is proposed. A big data platform for the data analysis in the shipyard is introduced and it is applied to the analysis of material requirement estimation to solve the problems in piping design by a designer. The regression model is developed from the big data of piping materials and verified using the existing data. This analysis can help a piping designer to estimate the exact amount of material requirement and schedule the purchase time.

• 한국컴퓨터정보학회논문지
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• 제10권3호
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• pp.183-188
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• 2005

블록암호알고리즘의 기본 구조인 Feistel 구조는 순차처리 구조이므로 병렬처리가 곤란하다. 그러므로 본 논문은 이러한 순차처리 구조를 변형하여 Feistel 구조가 병렬처리가 가능하도록 하였다. 이를 이용하여 본 논문은 병렬 Feistel 구조를 가지는 DES를 설계하였다. 제안된 병렬 Feistel 구조는 자체의 구조적 문제 때문에 pipeline 방식을 사용할 수 없어 데이터 처리속도와 데이터 보안사이에서 trade-off관계를 가질 수밖에 없었던 DES등과 같은 블록암호알고리즘의 성능을 크게 향상 시킬 수 있었다. 그러므로 Feistel 구조를 적용한 SEED, AES의 Rijndael, Twofish 등에 제안된 방식을 적용할 경우 지금보다 더욱 우월한 보안 기능 및 고속의 처리능력을 발휘하게 될 것이다.

• Asian Journal of Business Environment
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• 제2권2호
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• pp.23-26
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• 2012

Purpose - The study on the consumption structure of urban residents can help us to understand demand law and to grasp the changing consumption trend of people. Consumption structure is an important indicator reflecting the people's living standard. It is of realistic significance to study urban consumption structure. Research data and methodology - This study is carried out with data connected with urban residents from Shandong Statistical Yearbook for the period 2000-2010 analyzing eight commodity groups. The almost ideal demand system (AIDS) is one of the important models related to consumption structure. Results - This paper shows that firstly gives a brief introduction to AIDS. Then it makes an empirical analysis on the urban residents' consumption structure in Shandong province, China on the basis of AIDS model. Conclusions - the authorities are supposed to control the prices of HC, Foodstuff and Housing and encourage the consumption of HC, Housing, EE accordingly. At the same time, local government should increase the supply of goods connected with housing, HA, HC, and EE so as to attract more consumption from the urban residents in Shandong.

• 한국정보처리학회논문지
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• 제5권7호
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• pp.1883-1895
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• 1998

Java 프로그램밍 언어는 general-purpose concurrent object-oriented 언어로 알려져 있다. Java 언어는 개념과 구문 모두가 매우 간결하고 통일되어 있으며 인터넷 환경에서 최대한 활용되도록 하기 위하여 가상기계 개념을 도입하여 목적코드를 생성한다. 프로그래밍 언어에서 가장 중요한 부분이 data type 부분이다. Java 언어는 primitive type과 reference type을 지원한다. Primitive type과 reference type을 지원한다. Primitive type에는 boolean type integral type이 있다. Integral type에는 character, byte, short integer, integer, long integer, single-precision 과 double-precision floating point number가 있다. Reference type에는 class type, interface type, array type이 있다. 그러나 Java 언어는 general-purpose 프로그래밍 언어가 일반적으로 지원하는 structure type을 지원하지 않는다. 대신에 class type이 structure type을 포함하여 지원하는 구조로 되어 있다. 그러나 class type과 structure type은 서로 상이한 data type으로 판단된다. 따라서 Java 언어가 general-purpose의 성격을 가지기 위해서는 structure type을 명시적으로 지원하는 것이 바람직하다고 생각된다. 이 논문은 structure type을 Java 언어에 포함시킬 것을 제안한다.

• 한국CDE학회논문집
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• 제5권3호
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• pp.215-223
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• 2000

The product data exchange between heterogeneous CAB and PDM systems is a crucial issue for the integration of product development systems. STEP offers an efficient mechanism of product data exchange between heterogeneous systems. This paper introduces a UML-based mapping methodology for the product data models. The suggested mapping method has been applied to exchange the product structure data between CAD and PDM systems. Based on the STEP methods, we developed an interface module between a CAD system and a PDM system.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.65-65
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• 2003

After many genome projects, algorithms and software to process explosively growing biological information have been developed. To process huge amount of biological information, high performance computing equipments are essential. If we use the remote resources such as computing power, storages etc., through a Grid to share the resources in the Internet environment, we will be able to obtain great efficiency to process data at a low cost. Here we present the performance improvement of the protein secondary structure prediction (PSIPred) by using the Grid platform, distributing protein sequence data on the Grid where each computer node analyzes its own part of protein sequence data to speed up the structure prediction. On the Grid, genome scale secondary structure prediction for Mycoplasma genitalium, Escherichia coli, Helicobacter pylori, Saccharomyces cerevisiae and Caenorhabditis slogans were performed and analyzed by a statistical way to show the protein structural deviation and comparison between the genomes. Experimental results show that the Grid is a viable platform to speed up the protein structure prediction and from the predicted structures.

• Journal of Ship and Ocean Technology
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• 제9권3호
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• pp.23-32
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• 2005

Ship STEP(Standard for the Exchange of Product Model Data) which is composed of AP 215 (Ship Arrangement), AP 216(Ship Hull Form), AP 218 (Ship Structure), has been developed more than last 10 years and it is now at the stage just before IS(International Standard). It is expected that ship STEP would be used for the seamless data exchange among various CAD/CAM/CAE systems of shipbuilding process. In this paper the huge and complicated data structure of ship STEP is briefly reviewed at the level of ARM(Application Reference Model) and some abstract test cases which will be included as part of the standards are introduced. Basically ship STEP has common data model to be used without losing compatibility among those three different ship AP's, and it is defined as the modeling framework. Typical cases of data exchange during shipbuilding process, such as hull form data exchange between design office and model basin, midship structure data between shipbuilding yard and classification society are reviewed and STEP physical data are generated using commercial geometric modeling kernel. Test cases of ship arrangement at initial design stage and hydrodynamic data of crude oil carrier are also included.

• International Journal of Computer Science & Network Security
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• 제21권9호
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• pp.247-260
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• 2021

Data modeling is a process of developing a model to design and develop a data system that supports an organization's various business processes. A conceptual data model represents a technology-independent specification of structure of data to be stored within a database. The model aims to provide richer expressiveness and incorporate a set of semantics to (a) support the design, control, and integrity parts of the data stored in data management structures and (b) coordinate the viewing of connections and ideas on a database. The described structure of the data is often represented in an entity–relationship (ER) model, which was one of the first data-modeling techniques and is likely to continue to be a popular way of characterizing entity classes, attributes, and relationships. This paper attempts to examine the basic ER modeling notions in order to analyze the concepts to which they refer as well as ways to represent them. In such a mission, we apply a new modeling methodology (thinging machine; TM) to ER in terms of its fundamental building constructs, representation entities, relationships, and attributes. The goal of this venture is to further the understanding of data models and enrich their semantics. Three specific contributions to modeling in this context are incorporated: (a) using the TM model's five generic actions to inject processing in the ER structure; (b) relating the single ontological element of TM modeling (i.e., a thing/machine or thimac) to ER entities and relationships; and (c) proposing a high-level integrated, extended ER model that includes structural and time-oriented notions (e.g., events or behavior).

• 지구물리와물리탐사
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• 제11권1호
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• pp.26-33
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• 2008

큰 입사각을 가진 탄성파 반사법과 굴절법 자료의 분석은 지각 규모의 구조 연구에서 중요한 역할을 한다. 그러나, 관측된 자료로부터 적합한 속도 구조 모델을 바로 얻는 것은 상당히 어려운 일이며, 지각 구조 분석은 본질적으로 비선형 문제이기 때문에 구조 모델을 단계적으로 향상 시켜야만 한다. 광각 지각 구조 모델링에는 위상식별과 시행착오 전진 모델링과 같은 몇 가지 주관적인 과정들이 있다. 광각 자료 분석에서 이러한 주관적인 과정들은 결과 모델들의 유일성과 신뢰성을 감소시키기 때문에, 분석절차에서 주관성을 감소시키는 것이 중요하다. 이러한 관점에서, 우리는 지각 구조 모델의 개발에 사용될 PASTEUP과 MODELING이라는 2개의 소프트웨어를 설명하고 있다. PASETUP은 기록 단면도의 도시, 광각 탄성파 자료 분석 그리고 위상 피킹을 쉽게 해주는 대화식 응용프로그램이다. PASETUP은 신호대잡음 비를 향상시키고 위상식별을 도와주는 분석 기능과 다양한 필터를 갖추고 있다. MODELLING은 속도모델의 편집과 파선 모델링을 위한 대화식 응용프로그램이다. MODELING에 의해 계산된 주행시간은 PASTEUP에서 관찰된 파형과 바로 비교될 수 있다. 이것은 지각구조 분석에서 가장 주관적인 과정 중 하나인 주행시간 피킹이 필요 없기 때문에 지각 구조 모델링에서 주관성을 감소시킨다. MODELING은 편집 가능한 층서구조 모델을 다중 채널 탄성파(MCS) 반사파 자료의 시간 단면도와 비교할 수 있는 왕복 주시로 변환할 수 있다. 반사파 자료와 광각 자료의 구조 모델 사이의 직접 비교는 모델에 좀 더 신뢰성을 부여한다. 게다가 PASTEUP과 MODELING 둘다 큰 자료를 다루기에 효과적인 도구이다. 이 소프트웨어들은 광각 탄성파 자료를 이용한 좀 더 그럴듯한 지각-규모의 구조 모델을 개발하는데 도움을 준다.