• 전자공학회논문지SC
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• 제42권4호
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• pp.35-44
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• 2005

생체인식 기술 중 변별력과 활용성, 편리성이 뛰어난 얼굴인식 기술은 출입통제나 금융관련 업무 처리와 같이 보안관련 응용분야에서 필요성이 급속도로 요구되고 있다. 따라서 얼굴인식 알고리즘의 발전과 더불어 현 기술의 상태를 파악하고 발전 방향을 제시하기 위한 성능 시험 방법에 대한 연구 또한 중대한 이슈로 부각되고 있다. 본 연구에서는 얼굴인식 시스템의 성능 시험을 위한 프로토콜의 설계 기준을 제시하고 XM2VTS 데이터베이스를 사용하여 PCA를 기반으로 한 인식 시스템을 디자인하여 Identification 시나리오와 Verification 시나리오 상에서 성능 시험 결과를 제시한다.

• 한국항해학회지
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• 제15권3호
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• pp.1-11
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• 1991

As increasing needs of marine transportation , world merchant fleet and ship's size were enlarged and it caused frequent disasters in human lives and natural environment. By the reason of the above, they started to establish the Vessel Traffic System (VTS) at the European coast in 1960' and most of advanced contries established and managed it to prevent the sea traffic accidents in these days. The concept of traffic control at sea can be divided into three types. First, the initial gathering of informations about ship's identity and movement etc.. Second, monitoring of the traffic flow and amendment of instructions. Third , organization and direction of ships by allocating routes and speeds. Where the goal of traffic control is safety of traffics and developing effectiveness of navigation channel, if traffic volume is less tan channel capacity then the above first or second level of control would be sufficient but if it is bigger than that , more positive policy of control should be adopted as same as third type of the above. In this paper where the strategy of VTS is focused on the control of traffic density to be spread equality, as possible , all over the navigation channels and also improvement of effectiveness , it suggests algorithm to assign the vessels to the channels with balanced traffic density , and other algorithms using D.P. to sequence the vessels assigned to one channel in optimum order which decreases the mean waiting time in sense of channel effectiveness with numerical examples.

• 한국멀티미디어학회논문지
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• 제19권8호
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• pp.1377-1385
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• 2016

Conventional X-band marine radar has been used as one of the effective tools for collecting and retrieving ocean surface information parameters for three decades. Several wave information extracting algorithms have been designed in such a way that they can be utilized for efficiently estimating sea surface wave parameters such as current velocities, wave direction, significant wave heights in VTS (Vessel Traffic Service). However, their performances are still restricted. For the purpose of overcoming the performance limits, in this paper, first the conventional algorithms are analyzed and their performances are compared, and then a new control algorithm is proposed. Furthermore, we try to improve the estimation performances of typical wave parameters including wave directions and significant wave heights by introducing linear regression model in the process of computing wave information extraction. Through several simulations with the X-band radar images, it is shown that the proposed method is very effective in estimating the wave information compared to the real measured buoy data.

• 정보보호학회논문지
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• 제20권5호
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• pp.133-138
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• 2010

본 논문은 얼굴과 음성 정보를 사용한 다중 바이오 인증에서, 특정 단계의 융합과 결정 단계의 융합을 동시에 수행하는 다단계 융합 방법을 제안한다. 얼굴과 음성 특징을 1차 융합한 얼굴 음성 융합특징에 대해 Support Vector Machines(SVM)을 생성한 후, 이 융합특징 SVM 인증기의 결정과 얼굴 SVM 인증기의 결정, 음성 SVM 인증기의 결정들을 다시 2차 융합하여 최종 인증 여부를 결정한다. XM2VTS 멀티모달 데이터베이스를 사용하여 특징 단계 융합, 결정 단계 융합, 다단계 융합 인증을 비교 실험한 결과, 제안한 다단계 융합에 의한 인증이 가장 우수한 성능을 보였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전력기술부문
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• pp.12-14
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• 2007

A voltage transformer (VT) is used to transform a high voltage into a low voltage as an input for a metering device or a protection relay. VTs use an iron core which maximizes the flux linkage. The primary current of the VT has non-fundamental components caused by the hysteresis characteristics of the iron core. It causes a voltage drop in the winding impedances resulting in the error of the VT. This paper describes a compensation algorithm for the VT. The proposed algorithm can compensate the secondary voltage of VT by calculating the primary current from the exciting current of the hysteresis loop in the voltage transformer. In this paper, the exciting branch was divided into a non-linear core loss resistor and a non-linear magnetizing inductor. The performance of the proposed algorithm was validated under various conditions using EMTP generated data. Test results show that the proposed compensation algorithm can improve the accuracy of the VT significantly.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2010년도 추계학술대회
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• pp.180-181
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• 2010

선박에서 항해사의 안전운항을 효과적으로 지원하고 충돌사고를 방지하기 위해 다중선박의 충돌 위험도를 추정하는 알고리즘을 개발하였다. 선박 충돌위험도 추정 알고리즘은 선박들의 항행정보로서, AIS 정보를 사용하고, 퍼지 이론을 이용하여 충돌위험도를 계산한다. 지난 연구에서는, 고안된 알고리즘의 성능을 검증하기 위해 울산항 해상교통관제(VTS) 센터로부터 수집된, 실제 울산항에서 운행된 선박들의 AIS데이터를 기반으로 검증 시뮬레이션을 수행한 바 있다. 본 논문에서는 선박 충돌위험도 추정 알고리즘을 좀 더 정밀하게 검증하기 위해, 실제 해상충돌사고 데이터에 적용해 보고자 하였다. 이를 위해, 2009년 부산항에서 발생한 석유제품 운반선과 화물선간의 충돌사고에 대한 AIS 데이터를 수집하였고, 이를 이용하여 선박운항 시뮬레이터 기반, 재생 시뮬레이션을 수행하였다. 본 논문에서는 선박 충돌위험도 추정 알고리즘의 특징과, 실제 선박 충돌사고의 AIS 데이터에 대한 재생 시뮬레이션 결과에 대해 소개하였다.

• 한국항해항만학회지
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• 제34권10호
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• pp.727-733
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• 2010

해양사고에서 선박간의 충돌사고가 많은 부분을 차지하고 있으며, 상당수가 인적오류에 의해 발생되고 있다. 본 논문에서는 선박에서 항해사의 안전운항을 효과적으로 지원하고 충돌사고를 방지하기 위해 다중선박의 충돌 위험도를 추정하는 알고리즘을 개발하였다. 선박 충돌위험도 추정 알고리즘은 선박들의 항행정보로서 AIS 정보를 사용하고 퍼지 이론을 이용하여 충돌위험도를 계산한다. 지난 연구에서는 고안된 알고리즘의 성능을 검증하기 위해 울산항 해상교통관제(VTS) 센터로부터 실제 울산항에서 운행된 선박들의 AIS데이터를 수집하였고, 이를 기반으로 검증 시뮬레이션을 수행한 바 있다. 본 논문에서는 선박 충돌위험도 추정 알고리즘을 좀더 정밀하게 검증하기 위해 실제 해상충돌사고 데이터에 적용해 보고자 하였다. 이를 위해, 2009년 부산항에서 발생한 석유제품 운반선과 화물선간의 충돌사고에 대한 AIS 데이터를 수집하였고 이를 이용하여 선박운항 시뮬레이터 기반 재생 시뮬레이션을 수행하였다. 시뮬레이션 결과, 실제 사고 상황에 적용할 경우 충돌 사고가 일어나기 전에 충돌 위험을 표시하여 충돌사고를 경고할 수 있음을 확인할 수 있었다.

• 한국항해항만학회지
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• 제27권6호
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• pp.645-652
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• 2003

A virtual vessel traffic control system is introduced to contribute to prevent a marine accident such as collision and stranding from happening. Existing VTS has its limit. The virtual vessel traffic control system consists of both data acquisition by satellite remote sensing and a simulation of traffic environment stress based on the satellite data, remotely sensed data And it could be used to provide timely and detailed information about the marine safety, including the location, speed and direction of ships, and help us operate vessels safely and efficiently. If environmental stress values are simulated for the ship information derived from satellite data, proper actions can be taken to prevent accidents. Since optical sensor has a high spatial resolution, JERS satellite data are used to track ships and extract their information. We present an algorithm of automatic identification of ship size and velocity. It lastly is shown that based on ship information extracted from JERS data, a qualitative evaluation method of environmental stress is introduced.

• 음성과학
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• 제11권2호
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• pp.247-257
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• 2004

There has been many research efforts to overcome the problems of speech recognition in the noisy conditions. Among them, the model-based compensation methods such as the parallel model combination (PMC) and vector Taylor series (VTS) have been found to perform efficiently compared with the previous speech enhancement methods or the feature-based approaches. In this paper, a data-driven model compensation approach that adapts the HMM(hidden Markv model) parameters for the noisy speech recognition is proposed. Instead of assuming some statistical approximations as in the conventional model-based methods such as the PMC, the statistics necessary for the HMM parameter adaptation is directly estimated by using the Baum-Welch algorithm. The proposed method has shown improved results compared with the PMC for the noisy speech recognition.

• 한국항해항만학회지
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• 제39권5호
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• pp.377-384
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• 2015

The interpolation of missing AIS data can be used for recovering the lost data of a ship's state which is then able to produce useful information for VTS stations or other ships. Previous research has introduced some interpolating methods however there are some problems with regard to missing AIS data. This paper proposes one new method which includes linear interpolation, cubic Hermit interpolation and an identification mechanism to overcome some of those limitations, first AIS data regarding ship position, COG, SOG and HDG is divided into separate time series, then the characteristic of the missing data is investigated into through using an identification mechanism, an appropriate interpolation is selected to fit all the time series which matches the characteristics. Numerical experiments are carried out using real AIS data to validate the algorithm of this approach and the results are compared with the previous method, after which the actual missing area is suggested to be interpolated by the proposed method. The interpolation results show this approach can be applied well in practice.