• 한국해양공학회지
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• 제29권2호
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• pp.143-153
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• 2015

This paper presents the results of an experimental study on the motion of an FPSO (Floating production storage and off-loading) and the characteristics of the mooring systejavascript:confirm_mark('abe', '1');m according to the turret position. Model tests of a turret-moored FPSO were carried out in the Ocean Engineering basin of KRISO. The FPSO was moored using an internal turret and catenary mooring. The models (1/60 scale) that were prepared included the FPSO, turret, and mooring lines. The experiments were conducted in irregular waves and combined environments, with waves, currents, and winds. A time-domain simulation was performed using OrcaFlex. The motion response and mooring line tension from the present calculations were compared with the results of experiments, and the agreement was fairly good. In addition, the results showed that the weathervaning stability was improved when the position of the turret was moved in the bow direction.

• 생명과학회지
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• 제16권7호
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• pp.1229-1234
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• 2006

배지에 tetracycline이 없으면 사멸하는 평활근세포 (FADD-SMC)를 이용하여 metalloproteinase (MMP)와 사멸세포의 상관관계를 조사하였다. FADD-SMC를 tetracycline이 없는 배지에서 배양하는 경우 핵이 조각으로 잘라졌고 인산화한 p38과 ERK가 증가하고 MMP-9의 발현과 활성이 증가한 반면, cyclin D와 cyclin D의 발현은 감소하였다. 그리고 죽는 FADD-SMC에서 MMP-9의 발현은 immunofluorescen로 재확인하였다. MMP-9의 증가는 MAPK 억제제인 PD098059와 p38 MAPK 억제제인 SB203S80에 의하여 감소하였다. 그리고 MMP 억제제인 BB94는 FADD-SMC의 사멸을 감소시켰다.

• 한국어교육
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• 제28권1호
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• pp.113-139
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• 2017

Since the enactment of the "Framework Act on the Korean Language (herein after "Act ), researchers have focused their studies on measuring whether the Act played a huge role in providing Korean education. This can be confirmed by many, that the Act has indeed played a huge part in providing Korean language education. However, little attention was given to the validity of the education curriculum for prospective Korean language teachers as provided by the Act. Therefore, this survey has been conducted to provide an insight to teachers' perception of the Korean language curriculum for prospective teachers and will test whether such perception meets the standards in which the Act has been enacted. In this survey, we have received response on the importance of each domain and subject in the areas of Korean language education as viewed by the Korean language teachers. The results revealed the importance in the following order: Teaching Practice, Korean Linguistics, Korean Educational Linguistics, General Linguistics, and Korean Culture. These results strongly suggest that there is a need for the current curriculum, laid out by the Act, to be reconsidered to stress different levels of importance and time assignment for each category. The survey analysis shows the disparity in importance within the curriculum between the Act and the views in which the Korean language teachers perceive Korean language education. While further research is needed to confirm the analysis of this survey, this area of research will be instrumental in determining the suggestive shapes of the curriculum governed by the Act in the years to come.

• 아시안잔디학회지
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• 제20권2호
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• pp.213-221
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• 2006

본 연구는 토양 수분함량을 즉시 파악할 수 있는 Time Domain Radiometer(TDR)과 식물의 광합성 시 잎에서 반사되는 Reflectance를 통하여 식물의 상태를 파악할 수 있는 Multi-spectral radiometer(MSR)를 사용하여 난지형 잔디인 'Sea Isle 1' Seashore paspalum 과 'Floratam' St. Augustinegrass를 대상으로 토양수분함량과 Reflectance와의 상관관계를 파악하고자 시작하였다. 본 연구를 통해 토양 수분함량이 660, 694 wavelengths와 NDVI, LAI, stress index에서 높은 상관관계를 가지고 있음을 알 수 있었다. 이는 Sensor-based technology가 잔디의 수분요구 시점을 미리 파악할 수 있는 기술의 기초 자료로서 활용될 수 있으며 여러 다른 Sensor-based technology를 이용한 연구로 확대될 수 있을 것이다.

• 한국해양공학회지
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• 제33권3호
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• pp.214-221
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• 2019

A series of model tests was performed to evaluate the survivability of an articulated tower-type buoy structure under harsh environmental conditions. The buoy structure consisted of three long pipes, a buoyancy module, and top equipment. The scale model was made of acrylic pipe and plastic with a scale ratio of 1/22. The experiments were carried out at the ocean engineering basin of KRISO. The performance of the buoy structure was investigated under waves only and under combined environmental conditions from sea state (SS) 5 to 7. A nonlinear time-domain numerical simulation was conducted using the mooring analysis program OrcaFlex. The survivability of the buoy was analyzed based on three factors: the pitch motion, submergence of the top structure, and anchor reaction force. The model test results were directly compared to the results of numerical simulations. The effects of the sea state and combined environment on the performance of the buoy structure were investigated.

• 인터넷정보학회논문지
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• 제23권1호
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• pp.87-93
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• 2022

군(軍) PC의 99%는 윈도우 운영체제를 사용하고 있어 안전한 국방사이버공간을 유지하기 위해서는 윈도우 기반 악성코드의 탐지 및 대응이 상당히 중요하다. 본 연구에서는 윈도우 PE(Portable Executable) 포맷의 악성코드를 탐지할 수 있는 모델을 제안한다. 탐지모델을 구축함에 있어서는 탐지의 정확도보다는 급증하는 악성코드에 효율적으로 대처하기 위한 탐지모델의 신속한 업데이트에 중점을 두었다. 이에 학습 속도를 향상시키기 위해 복잡한 전처리 과정 없이 최소한의 시퀀스 데이터만으로도 악성코드 탐지가 가능한 Bidirectional LSTM(Long Short Term Memory) 네트워크를 기반으로 탐지모델을 설계하였다. 실험은 EMBER2018 데이터셋을 활용하여 진행하였으며, 3가지의 시퀀스 데이터(Byte-Entropy Histogram, Byte Histogram, String Distribution)로 구성된 특성 집합을 모델에 학습시킨 결과 90.79%의 Accuracy를 달성하였다. 한편, 학습 소요시간은 기존 탐지모델 대비 1/4로 단축되어 급증하는 신종 악성코드에 대응하기 위한 탐지모델의 신속한 업데이트가 가능함을 확인하였다.

• 대한전자공학회논문지SD
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• 제48권8호
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• pp.33-44
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• 2011

본 연구에서는 AMBA 3.0 AXI 프로토콜을 사용하여 고성능 및 저전력이 요구되는 MPSoC에 적합한 하이브리드 온-칩 버스구조를 설계하였다. AXI의 채널 중에서 트래픽이 많은 쓰기데이터 채널 및 읽기데이터 채널은 Crossbar 버스구조로 설계하여 고속 처리를 가능하게 하였다. 또한 MPSoC에서의 컴포넌트 추가에 따른 오버헤드(회로크기, 연결회선, 전력소모 등)를 줄이기 위해 트래픽이 적은 주소 채널과 쓰기 응답 채널은 Shared 버스구조로 공유하도록 설계하였다. 본 연구에서는 Hybrid 버스구조의 검증을 위해 Shared 버스구조 및 Crossbar 버스구조와 함께 시간, 공간, 파워 영역에서 각각 비교 실험하였다. $16{\times}16$ 버스 실험에서 Hybrid 버스구조는 Crossbar 버스구조와 비교해서 마스터의 대기시간은 약 9%, 전체 실행시간은 약 4%의 차이에 그쳐 비슷한 성능을 보여준다. 반면 오버헤드에서는 Crossbar 버스구조와 비교하여 회로 크기는 47%, 연결 회선 수는 52%, 동적 전력 소모는 66%의 감소 효과를 보인다. 따라서 본 연구에서 설계한 하이브리드 온-칩 버스구조는 Crossbar 버스 구조와 비교하여 고성능 및 저전력이 요구되는 MPSoC 인터커넥션에 매우 효과적임을 보이고 있다.

• 대한기계학회논문집A
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• 제34권5호
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• pp.619-628
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• 2010

차세대 의료기기 시장을 변화시킬 것으로 기대되는 형상기억합금(SMA) 기반의 최소침습용 의료기기는 시술자의 손동작과 같은 유연성과 섬세함을 구현할 수 있는 장점이 있다. 그러나 SMA의 비선형 열전기적 특성으로 인해 SMA 기반 차세대 의료기기 엑추에이터는 자유로운 방향조종 구현이 제한적이고 상용화에 있어서 큰 한계성으로 작용한다. 본 논문은 SMA의 효과적인 온도제어를 위해 전류-온도간의 개방루프 계단응답을 분석하고 1차 미분방정식 해와 비교하여 온도제어에 필요한 파라미터 $t_1$을 도출한 뒤 실험적으로 그 기능을 검증하였다. 또한 $t_1$은 전류를 입력으로 온도를 출력으로 하는 시불변 선형계의 특성함수의 폴(pole)이므로 주파수에 의한 온도제어에 관계된 파라미터인 것으로 나타났다. 본 논문의 결과는 SAM 기반의 차세대 의료기기 액추에이터의 효과적인 위치제어 설계에 응용될 수 있다.

• Journal of electromagnetic engineering and science
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• 제16권3호
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• pp.169-181
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• 2016

This work presents a new method for enhancing the performance of a dual band Planer Inverted-F Antenna (PIFA) and its lumped equivalent circuit formulation. The performance of a PIFA in terms of return loss, bandwidth, gain, and efficiency is improved with the addition of the proposed open stub in the radiating element of the PIFA without disturbing the operating resonance frequencies of the antenna. In specific cases, various simulated and fabricated PIFA models illustrate that the return loss, bandwidth, gain, and efficiency values of antennas with longer optimum open stub lengths can be enhanced up to 4.6 dB, 17%, 1.8 dBi, and 12.4% respectively, when compared with models that do not have open stubs. The proposed open stub is small and does not interfere with the surrounding active modules; therefore, this method is extremely attractive from a practical implementation point of view. The second presented work is a simple procedure for the development of a lumped equivalent circuit model of a dual band PIFA using the rational approximation of its frequency domain response. In this method, the PIFA's measured frequency response is approximated to a rational function using a vector fitting technique and then electrical circuit parameters are extracted from it. The measured results show good agreement with the electrical circuit results. A correlation study between circuit elements and physical open stub lengths in various antenna models is also discussed in detail; this information could be useful for the enhancement of the performance of a PIFA as well as for its systematic design. The computed radiated power obtained using the electrical model is in agreement with the radiated power results obtained through the full wave electromagnetic simulations of the antenna models. The presented approach offers the advantage of saving computation time for full wave EM simulations. In addition, the electrical circuit depicting almost perfect characteristics for return loss and radiated power can be shared with antenna users without sharing the actual antenna structure in cases involving confidentiality limitations.

• Asian Pacific Journal of Cancer Prevention
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• 제17권11호
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• pp.4999-5003
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• 2016

The testicular cancer (TCa) incidence is increasing in many countries, with age-standardized incidence rates up to 7.8/100,000 men in the Western world, although reductions in mortality and increasingly high cure rates are being witnessed at the same time. In Africa, where rates are lower, presentation is often late and morbidity and mortality high. Given this scenario, awareness of testicular cancer and practice of testicular self-examination among future first response doctors is very important. This study was conducted to determine knowledge and attitude to testicular cancer, and practice of testicular self-examination (TSE) among final (6th) year medical students. In addition, the effect of an intervention in the form of a single PowerPoint(R) lecture, lasting 40 minutes with image content on testicular cancer and testicular self examination was assessed. Pre and post intervention administration of a self-administered structured pre tested questionnaire was performed on 151 medical students, 101 of whom returned answers (response rate of 66.8%). In the TC domain, there was a high level of awareness of testicular cancer, but poor knowledge of the age group most affected, with significant improvement post intervention (p<0.001). Notable also was the poor awareness of the potential curability of TC, this also being improved following the intervention (p<0.001). A poor level of awareness and practice of testicular self-examination pre-intervention was found considering the nature of the study group..Respondents had surprisingly weak/poor responses to the question "How important to men's health is regular testicular self-examination?" Answers to the questions "Do you think it is worthwhile to examine your testis regularly?" and "Would you be interested in more information on testicular cancer and testicular self-examination?" were also suboptimal, but improved post intervention p<0.001, p<0.001 and p=0.037. Age, gender and marital status were without specific influence. In conclusion, this study showed poor levels of knowledge regarding epidemiology of TCa and its potential curability when detected early. There was also a poor awareness of, practice of, and poor attitudes to TSE. The significant improvement in these parameters post intervention indicates value in educational intervention. We recommend inclusion of TCa coverage and TSE teaching in the secondary school curriculum (targeting adolescents). Greater emphasis should also be given to testicular cancer in the curricula of medical schools and other training institutions for health care personnel.