• 한국정보통신학회논문지
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• 제16권4호
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• pp.812-820
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• 2012

본 논문에서는 지능형 감시 시스템에 부합하는 기울기 히스토그램 및 폐색 추적을 통한 다중보행자 추적 시스템을 제안한다. 먼저, 연속 영상에서 보행자의 특징을 이용하여 보행자를 검출한다. 보행자의 특징을 획득하기 위해 HOG(Histogram of Oriented Gradient)를 기반으로 기울기의 방향성을 이용한 블록별 히스토그램을 생성하고, Linear-SVM(Support Vector Machine)의 학습을 통해 보행자만을 분류한다. 다음으로 보행자의 위치정보를 이용하여 추적을 행한다. 마지막으로 추적이 끝날 경우 내용기반 검색이 가능한 움직임 궤적 디스크립터를 생성한다. 실험을 통해 제안한 방법이 기존 방법보다 빠르고 정확한 움직임 추적에 효과적임을 증명하였다.

• 전자공학회논문지SC
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• 제46권4호
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• pp.70-76
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• 2009

본 연구에서는 자동차 사고나 뇌졸중 둥에 의해 경추 이하의 마비나 손, 발 등의 움직임이 자유롭지 못한 사람들의 컴퓨터 사용을 돕고자 손이나 발을 이용하지 않고 머리의 움직임과 눈의 깜박임만으로 컴퓨터 마우스 제어가 가능한 장치를 제안하였다. 마우스의 위치는 각속도 센서를 이용하여 머리의 움직임으로 추정하고, 눈 깜빡임에 의한 클릭과 더블 클릭은 광센서의 시야를 방해하지 않는 위치에 장착하여 커 클위치와 이벤트를 검출하였다. 제안한 마우스의 공간 이동 능력과 이벤트 검출을 비교한 실험에서는 좌우, 상하 이동은 기존 마우스와 비교하여 속도 면에서는 큰 차이는 없었으나, 정확도가 조금 떨어지는 이유로 인하여 정확한 위치로 이동시키는데 소요시간이 3$\sim$4배 정도 더 필요하였다. 데드 존을 갖는 비선형 상대 좌표계 방식을 이용하여 주기적으로 적분 에러를 제거해야 하는 문제를 해결하였고, 이동 거리와 속도를 함께 고려하여 직관적인 마우스 포인터 제어가 가능하도록 하였다. 주변광의 영향을 최소화하도록 광원 제어 회로를 설계하여 외부 광원의 변화에도 마우스 이벤트 검출이 영향을 받지 않았다.

• 한국식품과학회지
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• 제45권2호
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• pp.156-160
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• 2013

우리나라에서 미승인 품목인 유전자변형 감자 EH92-527-1를 검출하기 위한 duplex PCR 검사법이 개발되었다. 감자의 내재유전자로 UDP-glucose pyrophosphorylase (UGP)가 선별되었고, 14개 다른 작물을 이용하여 특이성이 확인되었다. 유전자변형 감자에 삽입된 T-DNA 영역과 감자 게놈 사이의 연결 부위를 증폭하도록 프라이머 EH92-F/R 쌍이 제작되었고, 몇 개의 다른 유전자 변형 작물을 이용하여 특이성이 확인되었다. 서론에서 언급한 바와 같이 BASF사에서 각 개발된 유전자변형 감자 EH92-527-1과 BPS-A1020-5가 GBSS 유전자를 동일하게 포함하고 있으나 본 연구에서 개발한 검사법은 event-specific primers를 이용하였기 때문에 유전자변형 감자 EH92-527-1에만 특이성을 나타낸다. 이와 같이 개발된 duplex PCR 검사법의 검정한계치는 약 0.05%이다. 이러한 duplex PCR 검사법이 우리나라에 미승인 유전자변형 감자의 모니터링에 유용하게 사용될 것으로 판단한다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권9호
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• pp.5495-5501
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• 2013

Background: Alu elements are one of the most common repetitive sequences that now constitute more than 10% of the human genome and potential targets for epigenetic alterations. Correspondingly, methylation of these elements can result in a genome-wide event that may have an impact in cancer. However, studies investigating the genome-wide status of Alu methylation in cancer remain limited. Objectives: Oral squamous cell carcinoma (OSCC) presents with high incidence in South-East Asia and thus the aim of this study was to evaluate the Alu methylation status in OSCCs and explore with the possibility of using this information for diagnostic screening. We evaluated Alu methylation status in a) normal oral mucosa compared to OSCC; b) peripheral blood mononuclear cells (PBMCs) of normal controls comparing to oral cancer patients; c) among oral epithelium of normal controls, smokers and oral cancer patients. Materials and Methods: Alu methylation was detected by combined bisulfite restriction analysis (COBRA) at 2 CpG sites. The amplified products were classified into three patterns; hypermethylation ($^mC^mC$), partial methylation ($^uC^mC+^mC^uC$), and hypomethylation ($^uC^uC$). Results: The results demonstrate that the $%^mC^mC$ value is suitable for differentiating normal and cancer in oral tissues (p=0.0002), but is not significantly observe in PBMCs. In addition, a stepwise decrease in this value was observed in the oral epithelium from normal, light smoker, heavy smoker, low stage and high stage OSCC (p=0.0003). Furthermore, receiver operating characteristic (ROC) curve analyses demonstrated the potential of combined $%^mC$ or $%^mC^mC$ values as markers for oral cancer detection with sensitivity and specificity of 86.7% and 56.7%, respectively. Conclusions: Alu hypomethylation is likely to be associated with multistep oral carcinogenesis, and might be developed as a screening tool for oral cancer detection.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 추계종합학술대회 B
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• pp.265-269
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• 2008

Home health care with compact wearable units sounds to be a convenient solution for the elderly people living independently. This paper presents a method to detect fall from the other activities of daily living and also to classify those activities. This kind of ambulatory monitoring enables them to get an emergency help in the case of the fatal fall event and can provide their general health status by observing the activities being performed in daily life. A tri-axial accelerometer sensor is used to get the acceleration anomalies associated with the user's movements. The three axis acceleration data are transferred to the base station sensor node via an IEEE 802.15.4 compliant zigbee module. The base station sensor node sends the data to base station PC for an offline processing. This work shows the feature set preparation using the principal component analysis (PCA) for the designing of neural network. The work includes the most common activities of daily living (ADL) like Rest, Walk and Run along with the detection of fall events from ADL. The angle from the vertical is found to be the most significant feature parameter for classification of fall while mean, standard deviation and FFT coefficients were used as the feature parameter for classifying the other activities under consideration. The accuracy for detection of fall events is 86%. The overall accuracy for ADL and fall is 94%.

• 전력전자학회논문지
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• 제6권2호
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• pp.173-179
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• 2001

본 논문은 배전계통의 전력품질 개선을 위한 순시 전압강하 보상기의 제어 알고리즘에 대한 연구를 수행하였다. 특별히 순시적인 전압강하의 원인중 가장 대표적인 1선 지락사고 시에 발생하는 불평형과 비대칭 문제를 해석하기 위하여 새로운 대칭성분 검출 기법을 제안하였다. 제안되 방법은 간단한 연산만을 사용하며, 전압보상을 위한 대칭성분의 제어 기준값이 별도의 위상검출 과정을 거치지 않고도 직류 값으로 표현되도록 하였다. 그리고 기준전압의 발생 시에 IEC에서 규정하고 있는 UF와 MF를 사용하도록 하였다. 제안된 제어기법을 사용하면 보상장치는 매우 빠른 응답특성을 가지고 보상된 전압 파형의 총고조파왜형률(THD)도 매우 낮게 된다. 마지막으로 EMTDC 시뮬레이션과 실험을 통하여 제안된 방법의 타당성을 입증하였다.

• Safety and Health at Work
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• 제3권2호
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• pp.92-100
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• 2012

Objectives: The French National Occupational Diseases Surveillance and Prevention Network (RNV3P) is a French network of occupational disease specialists, which collects, in standardised coded reports, all cases where a physician of any specialty, referred a patient to a university occupational disease centre, to establish the relation between the disease observed and occupational exposures, independently of statutory considerations related to compensation. The objective is to compare the relevance of disproportionality measures, widely used in pharmacovigilance, for the detection of potentially new disease ${\times}$ exposure associations in RNV3P database (by analogy with the detection of potentially new health event ${\times}$ drug associations in the spontaneous reporting databases from pharmacovigilance). Methods: 2001-2009 data from RNV3P are used (81,132 observations leading to 11,627 disease ${\times}$ exposure associations). The structure of RNV3P database is compared with the ones of pharmacovigilance databases. Seven disproportionality metrics are tested and their results, notably in terms of ranking the disease ${\times}$ exposure associations, are compared. Results: RNV3P and pharmacovigilance databases showed similar structure. Frequentist methods (proportional reporting ratio [PRR], reporting odds ratio [ROR]) and a Bayesian one (known as BCPNN for "Bayesian Confidence Propagation Neural Network") show a rather similar behaviour on our data, conversely to other methods (as Poisson). Finally the PRR method was chosen, because more complex methods did not show a greater value with the RNV3P data. Accordingly, a procedure for detecting signals with PRR method, automatic triage for exclusion of associations already known, and then investigating these signals is suggested. Conclusion: This procedure may be seen as a first step of hypothesis generation before launching epidemiological and/or experimental studies.

• 한국시뮬레이션학회논문지
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• 제15권1호
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• pp.87-95
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• 2006

사이버 공격에 대한 새로운 보안시스템의 성능을 검증하기 위해서는 실 네트워크상에서의 검증이 필요하다. 하지만 현실적으로 대규모 분산 네트워크 환경에서의 검증은 어렵다. 이에 성능 검증을 위해 대규모 가상 네트워크 시뮬레이션 시스템이 필요하다. 본 논문에서는 대규모 네트워크를 표현할 수 있고, 프로세스 기반 사건 중심 시뮬레이션 시스템인 SSFNet을 사용하였다. 하지만 대규모 분산 네트워크상에서 보안시스템의 시뮬레이션을 SSFNet에서 수행할 수가 없다. 확장된 SSFNet내에는 IDS(Intrusion Detection System)의 보안모듈이 구성요소로 추가되었다. 추가적으로 IDS는 Snort의 기능을 모델링하여 구현하였다. 네트워크 시뮬레이션의 패킷을 쉽게 조작할 수 있도록 자바언어를 사용하여 패킷조작기를 개발하였다. 최종적으로 개발된 IDS와 패킷 조작기를 기능 검증을 위해 시뮬레이션을 수행하였다. 확장된 SSFNet은 향후 대규모 네트워크의 보안 시스템 시뮬레이터로 사용할 수 있다.

• Smart Structures and Systems
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• 제12권2호
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• pp.97-119
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• 2013

This paper presents numerical and experimental results on the use of guided waves for structural health monitoring (SHM) of crack growth during a fatigue test in a thick steel plate used for civil engineering application. Numerical simulation, analytical modeling, and experimental tests are used to prove that piezoelectric wafer active sensor (PWAS) can perform active SHM using guided wave pitch-catch method and passive SHM using acoustic emission (AE). AE simulation was performed with the multi-physic FEM (MP-FEM) approach. The MP-FEM approach permits that the output variables to be expressed directly in electric terms while the two-ways electromechanical conversion is done internally in the MP-FEM formulation. The AE event was simulated as a pulse of defined duration and amplitude. The electrical signal measured at a PWAS receiver was simulated. Experimental tests were performed with PWAS transducers acting as passive receivers of AE signals. An AE source was simulated using 0.5-mm pencil lead breaks. The PWAS transducers were able to pick up AE signal with good strength. Subsequently, PWAS transducers and traditional AE transducer were applied to a 12.7-mm CT specimen subjected to accelerated fatigue testing. Active sensing in pitch catch mode on the CT specimen was applied between the PWAS transducers pairs. Damage indexes were calculated and correlated with actual crack growth. The paper finishes with conclusions and suggestions for further work.

• International Journal of Automotive Technology
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• 제6권2호
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• pp.107-117
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• 2005

A distributed hardware-in-the-loop simulation (HILS) platform is developed for designing an automotive engine control system. The HILS equipment consists of a widely used PC and commercial-off-the-shelf (COTS) I/O boards instead of a powerful computing system and custom-made I/O boards. The distributed structure of the HILS system supplements the lack of computing power. These features make the HILS equipment more cost-effective and flexible. The HILS uses an automatic code generation extension, REAL-TIME WORKSHOP$^{ (RTW$^{) of MATLAB$^{ tool-chain and RT-LAB$^{, which enables distributed simulation as well as the detection and generation of digital event between simulation time steps. The mean value engine model, which is used in control design phase, is imported into this HILS. The engine model is supplemented with some I/O subsystems and I/O boards to interface actual input and output signals in real-time. The I/O subsystems are designed to imitate real sensor signals with high fidelity as well as to convert the raw data of the I/O boards to the appropriate forms for proper interfaces. A lot of attention is paid to the generation of a precise crank/ earn signal which has the problem of quantization in a conventional fixed time step simulation. The detection of injection! command signal which occurs between simulation time steps are also successfully compensated. In order to prove the feasibility of the proposed environment, a simple PI controller for an air-to-fuel ratio (AFR) control is used. The proposed HILS environment and I/O systems are shown to be an efficient tool to develop various control functions and to validate the software and hardware of the engine control system.