• 한국CDE학회논문집
• /
• 제18권2호
• /
• pp.104-112
• /
• 2013

Computer-based modeling and simulation (M&S) techniques have become an essential component in the development of new weapons systems. M&S techniques provide a means to simulate military training, strategies, military doctrines, and weapons acquisition processes. This paper proposes a small scale engagement scenario generation method. This work also includes a process for scenario generation and visualization. The proposed scenario generation methodology employs the Timed-FSA (finite state automata) and DFS (depth first search) algorithms. The proposed scenario generation method is verified using a one-on-one combat engagement scenario between two submarines. In addition, we suggest a scenario generation process including whole scenario generation and scenario visualization.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제8권1호
• /
• pp.83-101
• /
• 2016

This paper suggests an event-based scenario manager capable of creating and editing a scenario for shipbuilding process simulation based on multibody dynamics. To configure various situation in shipyards and easily connect with multibody dynamics, the proposed method has two main concepts: an Actor and an Action List. The Actor represents the anatomic unit of action in the multibody dynamics and can be connected to a specific component of the dynamics kernel such as the body and joint. The user can make a scenario up by combining the actors. The Action List contains information for arranging and executing the actors. Since the shipbuilding process is a kind of event-based sequence, all simulation models were configured using Discrete EVent System Specification (DEVS) formalism. The proposed method was applied to simulations of various operations in shipyards such as lifting and erection of a block and heavy load lifting operation using multiple cranes.

• 자동차안전학회지
• /
• 제4권1호
• /
• pp.5-11
• /
• 2012

This paper discusses the evaluation of the safety impact of the Adaptive Cruise Control (ACC) system in Korea. To evaluate the safety impact, this paper suggests an analysis method by using the test scenario and field operational test data. The test scenario is composed to represent the main component factor of the ACC system and ACC related accident situation such as rear-end collision, lane-change, and road-curvature, etc. Also, from the field operation test data, the system's potential to increase the safety can be measured ideally. Besides, field operational testdata was used to revise the expected safety impact value as Korean road conditions. By using the proposed evaluation method, enhanced safety impact of the ACC system can be estimated scientifically.

• 한국농공학회논문집
• /
• 제55권4호
• /
• pp.73-82
• /
• 2013

The main objective of this study was to evaluate Representative Concentration Pathways (RCP) scenarios-based flood risk at a Si-Gun level. A bias correction using a quantile mapping method with the Generalized Extreme Value (GEV) distribution was performed to correct future precipitation data provided by the Korea Meteorological Administration (KMA). A series of proxy variables including CN80 (Number of days over 80 mm) and CX3h (Maximum precipitation during 3-hr) etc. were used to carry out flood risk assessment. Indicators were normalized by a Z-score method and weighted by factors estimated by principal component analysis (PCA). Flood risk evaluation was conducted for the four different time periods, i.e. 1990s, 2025s, 2055s, and 2085s, which correspond to 1976~2005, 2011~2040, 2041~2070, and 2071~2100. The average flood risk indices based on RCP4.5 scenario were 0.08, 0.16, 0.22, and 0.13 for the corresponding periods in the order of time, which increased steadily up to 2055s period and decreased. The average indices based on RCP8.5 scenario were 0.08, 0.23, 0.11, and 0.21, which decreased in the 2055s period and then increased again. Considering the average index during entire period of the future, RCP8.5 scenario resulted in greater risk than RCP4.5 scenario.

• Journal of Electrical Engineering and Technology
• /
• 제11권1호
• /
• pp.47-54
• /
• 2016

Microgrids offer several reliability benefits, such as the improvement of load-point reliability and the opportunity for reliability-differentiated services. The primary goal of this work is to investigate the impacts of operating condition on the reliability index for microgrid system. It relies on a component failure rate model which quantifies the relationship between component failure rate and state variables. Some parameters involved are characterized by subjective uncertainty. Thus, fuzzy numbers are introduced to represent such parameters, and an optimization model based on Fuzzy Chance Constrained Programming (FCCP) is established for reliability index calculation. In addition, we present a hybrid algorithm which combines scenario enumeration and fuzzy simulation as a solution tool. The simulations in a microgrid test system show that reliability indices without considering operating condition can often prove to be optimistic. We also investigate two groups of situations, which include the different penetration levels of microsource and different confidence levels. The results support the necessity of considering operating condition for achieving accurate reliability evaluation.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제9권3호
• /
• pp.1014-1034
• /
• 2015

Location information of sensor nodes plays a critical role in many wireless sensor network (WSN) applications and protocols. Although many localization algorithms have been proposed in recent years, they usually target at dense networks and perform poorly in sparse networks. In this paper, we propose two component-based localization algorithms that can localize many more nodes in sparse networks than the state-of-the-art solution. We first develop the Basic Common nodes-based Localization Algorithm, namely BCLA, which uses both common nodes and measured distances between adjacent components to merge components. BCLA outperforms CALL, the state-of-the-art component-based localization algorithm that uses only distance measurements to merge components. In order to further improve the performance of BCLA, we further exploit the angular information among nodes to merge components, and propose the Component-based Localization with Angle and Distance information algorithm, namely CLAD. We prove the merging conditions for BCLA and CLAD, and evaluate their performance through extensive simulations. Simulations results show that, CLAD can locate more than 90 percent of nodes in a sparse network with average node degree 7.5, while CALL can locate only 78 percent of nodes in the same scenario.

• 한국노년학
• /
• 제31권4호
• /
• pp.1047-1065
• /
• 2011

본 연구는 노인장기요양보험 대상자 및 등급 확대에 따른 대상자 규모와 소요 재정을 추계함으로써 제도의 안정적 발전 및 지속가능성을 제고하고, 향후 정책개발에 기초자료 제공을 목적으로 한다. 연구방법은 문헌조사와 독일, 일본 등 선험국의 대상자 확대 정책을 고찰하여 대상자 확대 전략을 수립하고, 국민건강보험공단의 노인장기요양보험 대상자 증가추이, 노인성 질환대상자 증가 추이 분석, 현행 등급별 대상자의 급여 현황을 파악하여 등급 확대에 따른 재정소요를 예측하였다. 구체적인 방법으로 대상자 및 4등급 확대를 위한 범위 또는 범주를 시나리오별로 구체화하고 세분화된 급여 수준을 분석하여 재정을 추계하였다. 분석결과 대상자는 2010년 31만명에서 2015년 최소 42만명, 최대 57만명이었고, 이에 따른 관리운영비를 제외한 재정은 2010년 2.5조에서 2015년 최소 3.6조, 최대 4.0조인 것으로 추계되었다. 결과적으로 4등급 확대 시기는 제도안정화와 선험국의 선례와 경험을 함께 고려할 때 도입 4년차인 2012년 또는 5년 차인 2013년이 적정할 것으로 보인다. 이로인한 재정은 확대 초기 약 3천억원에서 1조 4천억원이 급여수준에 따라 예측되고, 확대이후 4등급 인정자 및 필요 재정지출은 점차 줄어들 것으로 예측된다. 선험국의 예를 볼때 급격한 4등급 확대보다는 시설 및 인프라가 감당할 수 있고, 재정 부담이 가능한 범위 내에서 확대 규모를 도출하는 것이 바람직할 것으로 판단된다. 본 연구는 시의성 있는 연구를 제시하여 향후 정확한 대상자 확대 및 재정안정화를 추구하도록 방향성을 제시하였다.

• 제어로봇시스템학회논문지
• /
• 제16권8호
• /
• pp.780-785
• /
• 2010

The OPRoS (Open Platform for Robotic Services) framework is proposed as an application runtime environment for service robot systems. For the successful deployment of the OPRoS framework, fault tolerance support is crucial on top of its basic functionalities of lifecycle, thread and connection management. In the previous work [1] on OPRoS fault tolerance supports, we presented a framework-based fault tolerance architecture. In this paper, we extend the architecture with component-based fault tolerance techniques, which can provide more simplicity and efficiency than the pure framework-based approach. This argument is especially true for fault detection, since most faults and failure can be defined when the system cannot meet the requirement of the application functions. Specifically, the paper applies two widely-used fault detection techniques to the OPRoS framework: 'bridge component' and 'process model' component techniques for fault detection. The application details and performance of the proposed techniques are demonstrated by the same application scenario in [1]. The combination of component-based techniques with the framework-based architecture would improve the reliability of robot systems using the OPRoS framework.

• 한국콘텐츠학회논문지
• /
• 제6권1호
• /
• pp.54-63
• /
• 2006

본 논문에서는 레거시 시스템에 대한 기존 도메인 분석의 문제점을 해결하기 위하여 동적 모델링을 기반으로 하는 확장된 워크플로우 메커니즘을 이용한 도메인 분석 방법론을 제안한다. 이 방법론을 WODA(Werldlow Oriented Domain Analysis)라 명명한다. 제안하는 절차를 통해 공통/비공통 컴포넌트를 식별 및 컴포넌트들의 클러스터를 추출할 수 있다. 이를 통해 새로운 시스템을 개발 시 효율적으로 재사용하고자 한다. 동적 분석으로 특정한 시스템에 발생 가능한 시나리오들을 식별한 후, 제안한 컴포넌트 테스트 플랜 매트릭스를 이용해 재사용성이 높은 컴포넌트와 컴포넌트 시나리오를 결정한다. 또한 컴포넌트 가중치 측정을 통해 재사용 가능한 컴포넌트들의 중요성과 빈도수를 인식하고 컴포넌트 시나리오들의 우선순위를 도출 할 수 있다. 구현한 자동화 모델링 도구인 WODA을 통해 UPS(Uninterrupted Power Supply)에 적용 사례를 소개한다.

• Journal of Electrical Engineering and Technology
• /
• 제11권3호
• /
• pp.560-574
• /
• 2016

This paper presents a novel method for power system harmonic estimation based on the Park transform. The proposed method firstly extends the signal to a group of three-phase signals in a-b-c coordinate. Then, a linear fitting based method is adopted to estimate the fundamental frequency. Afterwards, the Park transform is utilized to convert the three-phase signals from a-b-c coordinate to d-q-0 coordinate. Finally, the amplitude and phase of a harmonic component of interest can be calculated using the d-axis and q-axis components obtained. Simulation studies have been conducted using matrix laboratory (MATLAB) and power system computer aided design/electromagnetic transients including direct current (PSCAD/EMTDC). Simulation studies in MATLAB have considered three scenarios, i.e., no-frequency-deviation scenario, frequency-deviation scenario and the scenario in the presence of inter-harminics. The results have demonstrated that the proposed method achieves very high accuracy in frequency, phase and amplitude estimation under noisy conditions, and suffers little influence of the inter-harmonics. Moreover, comparison studies have proved that the proposed method is superior to FFT and Interpolated FFT with the Hanning Window (IpFFTHW). Finally, a popular case in PSCAD/EMTDC has been employed to further verify the effectiveness of the proposed method.