• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.11
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• pp.903-910
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• 2020

This paper introduces a simulator to assess the impacts of the wind and the airframe vibration on the performance of the Active Electronically Scanned Array (AESA) radar mounted in an aircraft. The AESA radar is mounted on the nose cone of an aircraft, and vibration occurs due to the drag force. This vibration affects the behavior of the AESA radar and can cause phase errors in signal. The simulator adopts the geometric model for nose cone, the mathematical models on the rigid-body dynamics of the aircraft, the average/turbulent winds, and the mode/ambient vibrations to compute the position and the attitude of the radar accurately. Numerical studies reflecting a set of test scenarios were conducted to demonstrate the effectiveness of the developed simulator.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.213-213
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• 2011

남강은 낙동강에 유입되는 지류 중 가장 큰 하천으로서 낙동강 하류의 수질에 매우 큰 영향을 미치고 있다. 남강댐은 저수 용량에 비해 유역면적이 주요 저수지들에 비하여 월등하게 크므로 홍수시 순간적으로 다량의 유량 및 오염물질이 방류되어 낙동강에 유입되는 특성을 가지고 있다. 남강댐은 서북측에서 유입되는 경호강과 남쪽에서 댐축과 가까이 유입되는 덕천강이 공간적으로 멀리 떨어져 있음으로 인해, 주요 유입물질이 유입되는 시기에 횡방향 및 종방향으로 농도차이를 나타내고 있으며, 과거에 설치되었던 댐이 수중에 존재함으로 인해 국지적인 정체현상이 발생하고 있다. 남강은 현재 경남권은 물론, 거제 및 부산권의 용수원을 공급하거나 예정으로 있으므로 수질관리에 가장 큰 우선순위를 두어야 한다. 남강댐의 합리적인 수질관리를 위해서는 호 내의 공간적 시간적 수질변화에 대한 이해와 수질변화 여건에 있으며 이용되는 만큼 호 내의 정밀한 유체거동 해석이 필수적이다. 본 연구에서는 남강댐의 수리-수질 특성을 진단하고 예측하기 위하여 3차원 수리동역학 모델인 EFDC와 수질모델인 WASP을 연계하여 사용하였다. 유량 경계조건은 한국수자원공사 및 국가수자원관리 종합 정보시스템(WAMIS)의 남강댐 운영 자료를 바탕으로 남강댐의 유입량과 유출량 자료를 작성하였다. 남강으로 유입되는 지천 및 호 내의 수온, SS 및 수질농도 등은 환경부의 물환경정보시스템의 월 측정자료를 사용하였으며, 기상조건은 진주 기상대의 자료를 사용하였다. 본 연구에서 가용한 입력자료를 이용하여 남강댐의 수리 및 수질 및 부유물질 특성을 모의하였으며 EFDC-WASP 모델을 이용하여 성공적인 보정이 가능한 것을 확인하였다. 그러나 자세한 분석과 대책을 수립하기 위해서는 남강댐의 유입 수질 및 유량 자료에 대한 실질적인 모니터링이 수행되는 것이 필요하다고 판단된다.

• The KIPS Transactions:PartD
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• v.12D no.7 s.103
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• pp.993-1000
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• 2005

Recently, software quality evaluation based on ISO/IEC 9126 and ISO/IEC 14598 has been widely accepted in various areas. However, these standards for software quality do not provide practical guidelines to apply the quality model and the evaluation process of software product=5. And the qualify management in most software projects has been conducted by managing defects without applying the standards for software qualify. Thus, we present a quantitative quality evaluation approach of artifacts in the Component Based Development (CBD). Particularly, our evaluation approach allows most of the standard evaluation process and adopts a quantitative quality model which uses the weights of quality characteristics obtained through carefully selected questionnaires for stakeholder and Analytic Hierarchical Process(AHP). Moreover, we have also examined the proposed evaluation approach with applying the checklists for the artifacts of the CBD to a small-scale software project. As a result, we believe that the proposed approach will be helpful for acquiring the high quality software.

• The KIPS Transactions:PartD
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• v.17D no.5
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• pp.359-370
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• 2010

As web 2.0 becomes one of the important architecture styles, more web applications adopt single page structure instead of multiple web pages and navigations between pages. A single page web application client, called a mashup client in this paper, interfaces more than one services and allows users to navigate in the page. A mashup client page includes complicated functions and has to handle various styles of services and user requirements, and therefore is usually developed manually. In this paper, we propose a model driven code generation approach for in-page navigations. We propose a page model and view navigation design approach, applying REST service architecture patterns. Then, we consider type conditions for each view to have service calls or navigation controls. Also, we developed an XForms page code generation system to demonstrate the efficiency of the proposed method. The developed system generates mashup client pages including navigation controls between services and views. This system can generate ready to use codes from service specifications, so this can help to reduce the development overhead. Moreover, our approach is based on formal model and navigation patterns so the generated result code is simple and easy to understand, and includes only the necessary controls. Therefore, the proposed approach can be more effective for the case of a large number of services.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.8
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• pp.243-250
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• 2020

Knowledge graph-based question answering not only requires deep understanding of the given natural language questions, but it also needs effective reasoning to find the correct answers on a large knowledge graph. In this paper, we propose a deep neural network model for effective reasoning on a knowledge graph, which can find correct answers to complex questions requiring multi-hop inference. The proposed model makes use of highly expressive bilinear graph neural network (BGNN), which can utilize context information between a pair of neighboring nodes, as well as allows bidirectional feature propagation between each entity node and one of its neighboring nodes on a knowledge graph. Performing experiments with an open-domain knowledge base (Freebase) and two natural-language question answering benchmark datasets(WebQuestionsSP and MetaQA), we demonstrate the effectiveness and performance of the proposed model.

• Journal of Korean Society of Steel Construction
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• v.15 no.5 s.66
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• pp.509-518
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• 2003

In this study, we carried out nonlinear analysis according to various interface nonlinear models by interaction magnitude, and analyzed interface behavior such as distribution of tangential traction and relative slip in steel-concrete composite structure. As a result of this study, tangential traction and relative slip of interface is rapidly increased at the steel plate-concrete interface, especially at the neutral region, rather than tensile, as opposed to the T beam-concrete interface. In transverse direction, it has gradually reduced to go outside from loading position. In longitudinal direction, it was minimum at the central region near the loading point, maximum at 0.6-0.7L from support and gradually reduced as it nears support. Moreover, as the load is increased, the failure of interface gradually expands from the maximum tangential traction position to the entire region. It is expected to provide fundamentality for interface behavior and load-carrying mechanism, and for the design of bending and shear connection of steel-concrete composite structure.

• Journal of Internet Computing and Services
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• v.10 no.4
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• pp.177-187
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• 2009

Typical RFID-device applications have provided users to each vendor-specific interface for supporting control and management of RF-tags and readers within their managed domain. Also, typical RFID-business applications have been implemented by using each event-data structure of RF-readers or RFID middlewares. RFID infrastructure managers, thus, are difficult to handle individual control and management specifications for managed RF-tags, devices and systems. Most RFID application services, also, are attached to providing visibility and traceability of an RF-tag item. To solve these problems, this paper proposes an RFID service management policy information model which supports to define unified control and management for heterogeneous RFID devices, middlewares and applications. This paper describes an example procedure that an RFID service management policy definition based on the proposed model is adaptively transformed and executed on a specific RFID sub-infrastructure.

• Journal of Technology Innovation
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• v.22 no.2
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• pp.247-285
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• 2014

Despite the important role of the transformational leadership and Creative Climate to achieve firms' sustainable competitive advantage, there has been limited empirical studies linking the transformational leadership and creative climate in employee's innovative performance. This study investigated the impact of transformational leadership on innovative performance based on employees of R&D department in IT services. This paper also investigated the mediating role of creative climate and moderating role of employee's innovative tendency in this relationship. Main findings of our empirical analysis are as follows. While the relationships between transformational leadership and innovative performance was positively associated, creative climate had positive effect on innovative performance. As expected, we also found that the creative climate had positively mediated the relationship between transformational leadership and innovative performance. Also, the innovative tendency has statistically significant moderating effect on this relationship. Based on the findings, we have suggested theoretical and practical implications while future research directions with limitations of the research are discussed.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.402-402
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• 2012

최근 반도체 공정 중 fluorocarbon (CxHyFz) 가스와 함께 플라즈마 밀도가 큰 유도결합형 플라즈마을 사용한 식각장비가 많이 사용되고 있다. 특히 저 유전상수 값을 가지는 박막을 밀도가 큰 플라즈마와 함께 fluorocarbon 가스를 이용하여 식각을 하게 되면 매우 복잡한 현상이 생긴다. 따라서 식각률에 대한 모델을 세우고 적용하는 일이 매우 어렵다. 본 연구에서는 CF4가스를 Ar가스와 함께 혼합하고 기판 플라즈마와 유도결합형 플라즈마를 동시에 가진 식각장비를 사용하여, 저 유전상수 값을 갖는 박막을 식각하였다. 또한, 간단한 식각모델인 Langmuir adsorption model를 이용하여 식각률(Etch rate)에 대한 합리적인 이해를 얻기 위해, 기판과 유도결합형 플라즈마의 파워에 따른 식각률을 계산하고, 식각모델에서 사용되는 매개변수인 이온플럭스(Ion Flux)와 식각수율(Etch yield)을 연구하였다. 기판의 플라즈마 파워가 20에서 100 W 증가하면서 식각률이 269에서 478 nm/min로 증가하였으며, 식각수율이 0.4에서 0.59로 증가하는 것을 관찰하였다. 반면에 기판의 플라즈마 파워 증가에 따라 이온 플럭스는 3.8에서 $4.7mA/cm^2$로 변화가 크지 않았다. 또한, 유도결합형 플라즈마의 파워가 100에서 500 W 증가하면서, 식각률이 117에서 563 nm/min로 증가하였으며, 이온플럭스가 1.5에서 $6.8mA/cm^2$으로 변화하였다. 그러나, 식각수율은 0.46에서 0.48로 거의 변화하지 않았다. 그러므로 저 유전상수 값을 가지는 박막 식각의 경우, 기판의 플라즈마는 식각수율을 증가시키며 유도결합형 플라즈마는 이온 플럭스를 증가시켜 박막 식각에 기여하는 것으로 사료된다.

• Journal of Internet Computing and Services
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• v.10 no.5
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• pp.153-163
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• 2009

It is necessary to identify the use cases of the supplier systems in order to define new service using their functions. Current use case modeling techniques, however, do not represent the external use cases clearly, because the external system is represented only by an actor. This ambiguity of the modeling technique declines the comprehensiveness of the model, and does not limit the scope of the target system explicitly. In this paper, we propose the extended use case modeling technique for service-oriented computing. This modeling technique enables the definition of external use cases and components. They are used to limit the boundary of the target system, and the relationship between them are modeled by the realization of external use cases. The proposed technique uses UML stereotype extension mechanism. so the compatibility with current use case modeling technique is preserved.