• 대한산업공학회지
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• 제37권3호
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• pp.264-270
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• 2011

A new method for creating a logical data model is proposed. The logical data model developed by the method defines table, primary key, foreign key, and fields. The framework of the logical data model is constructed by modeling the relationships between events and their related entity types. The proposed method consists of a series of objective and quantitative decisions such as maximum cardinality of relationships and functional dependency between the primary key and attributes. Even beginners to database design can use the methology as long as they understand such basic concepts about relational databases as primary key, foreign key, relationship cardinality, parent-child relationship, and functional dependency. The simple and systematic approach minimizes decision errors made by a database designer. In practial database design the method creates a logical data model in Boyce-Codd normal form unless the user of the method makes a critical decision error, which is very unlikely.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.244-245
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• 2021

Design VE (Value Engineering) has been basic design and implementation design separately, but due to the recent change in guidelines, it is changing to implement only once in the implementation design stage. However, in the implementation design stage, construction costs, plans, and specifications based on the volume details are almost completed. Therefore, it is effective to perform the function analysis step after identifying information analysis and key issues through CostModeling based on functional center for the selected target in the process of implementing the VE performance procedure.

• 산업공학
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• 제16권spc호
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• pp.45-48
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• 2003

Entity-relationship modeling for designing relational database is a very complicated thinking process that requires extensive knowledge and experiences. It is very likely that designers make mistakes in this process. In order to minimize the mistakes, a systematic method to guide the thinking process is needed. In this research, an entity-relationship modeling system is developed, which resolves the whole process of information modeling, data modeling, and functional dependency relationship analysis into small and simple decision-making steps. Therefore, it can reduce the possibility of making decision errors and improve the efficiency of the modeling process. It's functionality and efficiency is verified through some modeling examples. It is expected that the modeling system can be commercialized, if some functions are added, such as detection, warning, and correction of decision errors, and educational help.

• 정보통신설비학회논문지
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• 제9권1호
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• pp.13-18
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• 2010

As the importance of non-functional requirements has increased, many researchers have become interested in the software development process for non-functional requirements including the notation, modeling, and assessment of non-functional requirements. However, the characteristics of non-functional requirements are so sophisticated and there are many topics which have not been solved until now. In order to address one of the unsolved problems, we propose a systematic software development process to support the management of non-functional requirements. The process consists of six steps, each of which is composed of detailed activities. Using the proposed process, the non-functional requirements can be managed and modeled more effectively and systematically than previous ones.

• International Journal of CAD/CAM
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• 제3권1_2호
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• pp.13-17
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• 2003

Hybrid method of representing geometric entities as combination of boundary (B-rep) and functional (F-rep) representations is presented which can be used as a basis of solid modeling kernel. It contains whole functionality of classic B-rep kernel, and also supports enveloping (sweep of solid body). Principles and keysolutions are considered. Example of a real task that comes from gearing is provided.

• 한국항공우주학회지
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• 제37권5호
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• pp.450-456
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• 2009

수동형 진동제어 방식과 같이 시스템이 안정되며, 수동형에 비해 높은 제진 효과가 기대되는 반능동 진동제어 방식은 시스템의 안정화가 요구되는 우주구조물의 제진방법에 유효한 진동제어 방식중 하나이다. 본 논문에서는 유연우주트러스구조물의 진동제어를 위해 고안된 반능동 댐퍼내 작동유체의 질량을 모델링에 고려했을 경우의 제진특성을 분석하였고 댐퍼내 작동유체의 점성이 부족감쇠를 유지 할 경우, 작동유체 질량 적용에 따른 반능동 댐퍼의 제진효과를 확인하였으며 이를 토대로 반능동 댐퍼의 성능향상을 위한 설계방법을 제시하였다.

• 대한안전경영과학회지
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• 제15권3호
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• pp.133-141
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• 2013

As a work analysis technique, Work Domain Analysis (WDA) aims to identify the design knowledge structure of a work domain that human operators interact with through human-system interfaces. Abstraction hierarchy (AH) is a multi-level, hierarchical knowledge representation framework for modeling the functional structure of any kinds of systems. Thus, WDA based on AH aims to identify the functional knowledge structure of a work domain. AH has been used in a range of work domains and problems to model their functional knowledge structure and has proven its generality and usefulness. However, many of researchers and system designers have reported that it is never easy to understand the concepts underlying AH and use it effectively for WDA. This would be because WDA is a form of work analysis that is different from other types of work analysis techniques such as task analysis and AH has several unique characteristics that are differentiated from other types of function analysis techniques used in systems engineering. With this issue in mind, this paper introduces the concepts of WDA based on AH and offers a comprehensive list of references. Next, this paper proposes a set of principles for effectively applying AH for work domain analysis, which are developed based on the author's experiences, consultation with experts, and literature reviews.

• 한국CDE학회논문집
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• 제12권3호
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• pp.163-170
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• 2007

A torque converter, connected to a transmission/transaxle input shaft, connects, multiplies and interrupts the flow of engine torque into the transmission. Damper springs are usually equipped in a torque converter to convert stably the torque power supplied from engine. Damper Springs generally have the most flexible design variables among vehicle transmission parts, so that they could be effective design factors to improve the entire vehicle's performance. Damper spring, however, has geometric complexity after it equipped in a torque converter. For that reason, modeling a damper spring requires expert's knowledge to determine many design parameters and satisfy the functional requirements at the same time. In this paper, we introduce an optimum design method applied in detailed-design stage to reduce design process and financial loss caused by adequate design. Many design variables have to be classified and structuralized for Optimization. This also could make designer concentrate on functional requirements of damper spring, not on design possibility. In addition, modeling an assembled spring has technical restriction with primitives of the current major CAD solutions because of complexity of assembled spring shape. Thus, one of modeling solution presented in this paper since detailed and exact modeling is important for CAE or DMU.

• 한국시뮬레이션학회논문지
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• 제19권2호
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• pp.157-164
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• 2010

우수하고 신뢰성 있는 통신 시스템의 개발을 위해 시스템에 대한 기능 검증과 성능 평가가 모두 필수적인데 반해 이들은 주로 형식 언어 도구를 이용한 기능 모델링과 전문 네트워크 성능 평가 도구에 의한 성능 모델링을 통해 개별적으로 수행되어 왔다. 그러나 한 시스템을 별도로 중복하여 모델링 하는 것은 비용의 증가와 모델 간 불일치를 가져오게 된다. 본 논문은 이 문제를 해결하기 위해 SDL-OPNET 코-시뮬레이션을 통해 SDL로 설계된 통신 프로토콜의 성능을 평가하는 통합 설계 기법을 제안한다. 제안 기법은 Tau의 환경함수와 OPNET의 외부시스템 모듈을 이용하는 코-시뮬레이션 시스템의 설계 방법을 제시한다. InRes 프로토콜이 예로 사용되어 제안 기법의 적용가능성과 효용성을 보여준다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1591-1598
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• 2011

The objective of this paper is to study how to apply the functional models in the design reviews and the validation of the subsequent design specifications and standards in the urban rail transit standardization program. The functional models can be obtained based on the requirements. Specifically, the requirements are first represented by the use case and sequence diagrams and then the results are transformed into the functional models using the Systems Modeling Language (SysML) diagrams and the FFBD (Functional Flow Block Diagram) and others. Based on the results of the study, it can be checked whether the original requirements have been reflected properly in the designs. Also, it can be seen that how the possible changes in the requirements affect the functions and thus how the designs should be changed accordingly.