• 융합보안논문지
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• 제10권2호
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• pp.11-17
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• 2010

최근의 기술 발전은 무선 통신의 발달과 새로운 센서 기술은 저비용, 저전력 다기능 센서노드의 개발을 가능케 했으며, 더불어 소형화, 근거리 무선 통신 등을 통하여, 소형의 센서 노드들을 군집화되고 있다. 본 연구에서는 모바일 센서들의 위치를 반복적으로 추적하기 위한 셀 내 위치 측정을 고려한다. 반복적인 위치 추적을 통하여 센서들의 위치를 좀 더 정확하게 추정할 수 있다. 이를 위하여 본 연구에서는 수신신호세기를 이용하여 모바일 노드의 정확성을 실험하고 분석한다.

• 품질경영학회지
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• 제33권3호
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• pp.91-104
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• 2005

Tolerance analysis plays an important role in design and manufacturing stages for reducing manufacturing cost by improving producibility. In most production processes encountered in practice, a process mean may shift or drift in the long run although process is in control. This study discusses the feasibility of three most common inflation factors(Bender, Gilson and Six Sigma) as a correction to Root Sum of Squares(RSS) method to compensate heuristically for a shift of process mean and nonnormal component distributions from simulation experiments and proposes the guidelines for choosing the inflation factor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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• pp.181-182
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• 2008

In this paper, we present the design of an electromagnetic scanning mirror with rotated serpentine springs. We considered three types of torsional springs: simple beam springs (SBS), classic serpentine springs (CSS), and rotated serpentine springs (RSS). The analysis was done for an electrical resistance, differences in the mode-frequency, and resonances regarding to spring thickness. Electromagnetic coils under the mirror plate were also analyzed for power consumption and the mechanical deflection. From the analysis result, RSS and electromagnetic coils were designed for the silicon scanning mirror.

• 제어로봇시스템학회논문지
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• 제14권8호
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• pp.824-836
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• 2008

Relaxed static stability(RSS) concept has been applied to improve aerodynamic performance of modern version supersonic jet fighter aircraft. Therefore, flight control systems are necessary to stabilize an unstable aircraft, and provides adequate handling qualities and achieve performance enhancements. Standard FCSDVP (Flight Control System Design and Verification Process) is provided to reduce development period of the flight control system. In addition, if this process is employed in developing flight control system, it reduces the trial and error for development and verification of flight control system. This paper addresses the flight control system design and verification process for the RSS aircraft utilizing design goal based on military specifications, linear and nonlinear system design and verification based on universal software, handling quality test based on HILS(Hardware In-the-Loop Simulator) environment, and ground and flight test results to verify aircraft dynamic flight responses.

• International Journal of Aeronautical and Space Sciences
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• 제8권1호
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• pp.21-31
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• 2007

Relaxed Static Stability (RSS) concept has been applied to improve aerodynamic performance of modern version supersonic jet fighter aircraft. The T-50 advanced supersonic trainer employs the RSS concept in order to improve the aerodynamic performance. And the flight control system stabilizes the unstable aircraft and provides adequate handling qualities. The T-50 longitudinal control laws employ a proportional-plus-integral type controller based on a dynamic inversion method. The longitudinal dynamic modes consist of short period with high frequency and phugoid mode with low frequency. The design goal of longitudinal control law is optimization of short period damping ratio and frequency using Lower Order Equivalent System (LOES) complying the requirement of MIL-F-8785C. This paper addresses phugoid mode characteristics such as damping ratio and natural frequency that is affected by the nonlinear control laws such as angle of attack limiter, auto pitch attitude command system and autopilot of pitch attitude hold.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권1호
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• pp.87-107
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• 2015

Considering the localization estimation issue in mixed line-of-sight (LOS)/non-LOS(NLOS) environments based on received signal strength (RSS) measurements in wireless sensor networks, a grid-based correlation method based on the relationship between distance and RSS is proposed in this paper. The Maximum-Likelihood (ML) estimator is appended to further improve the localization accuracy. Furthermore, in order to reduce computation load and enhance performance, an improved recursively version with NLOS mitigation is also proposed. The most advantages of the proposed localization algorithm is that, it does not need any prior knowledge of the propagation model parameters and therefore does not need any offline calibration effort to calibrate the model parameters in harsh environments, which makes it more convenient for rapid implementation in practical applications. The simulation and experimental results evidence that the proposed localization algorithm exhibits good localization performance and flexibilities for different devices.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2003년도 추계학술발표논문집 (중)
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• pp.861-864
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• 2003

RSS(RDF Site Summary)는 웹 사이트의 콘텐츠를 간단하게 기술하고 RSS 수집기는 사용자에게 이를 적절한 형식으로 보여준다. 그러나 현재의 RSS는 자신의 콘텐츠에 대해서만 기술하고 있어서 웹 자원의 검색 측면에서 볼 때 사용자는 그와 유사한 콘텐츠를 갖는 다른 웹 사이트를 찾는데 또 다른 노력을 들여야 한다. 본 논문에서는 현재의 RSS에 다른 웹 사이트로 연결되는 추가적인 요소를 통하여 웹 자원의 탐색에 RSS를 이용할 것을 제안한다.

• Communications for Statistical Applications and Methods
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• 제14권3호
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• pp.641-648
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• 2007

We propose the new sampling method, called modified ranked ordering set sampling (MROSS). Kim and Kim (2003) suggested the sign test using the ranked ordering set sampling (ROSS), and showed that the asymptotic relative efficiency (ARE) of ROSS against RSS for sign test increases as sample size does. We propose the estimator for the population mean using MROSS. The relative precision (RP) of estimator of the population mean using MROSS method with respect to the usual estimator using modified RSS is higher, and when the underlying distribution is skewed, the bias of the proposed estimator is smaller than that of several ranked set sampling estimators.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.7-10
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• 2002

The diagnosis of faults of machine tool, which is controlled by CNC and PLC, is generally based on ladder diagram of PLC. Because sequential controls for CNC and servo motor are mostly processed in PLC. However, when fault is occurred, a searching for logical relation to fault reasons is required a lot of fault experiences and times, because PLC program has step structure. In this paper, FDS(Fault Diagnosis System) is developed and implemented to machine tool with open architecture controller in order to find the reason of fault lastly and correctly. The diagnosed reasons for fault are tele-serviced on web through developed RSS(Remote Service System). The operationability and usefulness of developed system are evaluated on specially manufactured machine tool with open architecture CNC. The results of this research can be the model of remote monitoring and fault diagnosis system of machine tool with open architecture CNC.

• 인터넷정보학회논문지
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• 제19권2호
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• pp.9-15
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• 2018

This paper proposes an energy efficient adaptive relay station ON/OFF scheme with different frequency reuse factors (FRFs) to enhance the system throughput and reduce the transmission energy consumption for the transparent mode of 2-hop cellular relay networks (CRNs) based on orthogonal frequency division multiple access and time division duplex. In the proposed scheme, the base station turns on or off the relay stations (RSs) when they are overutilized and undertuilized based on the traffic density of the cell coverage, respectively. Through the simulation results, we show that the proposed scheme outperforms the conventional CRN in terms of the energy consumption with the same system throughput. Further, in order to increase the system throughput with low energy consumption, the best way is FRF 1 when the number of operating RSs is up to 4 and FRF 2 otherwise.