• 제목/요약/키워드: 김대성

검색결과 384건 처리시간 0.038초

극단화소 기반의 Hyperion 데이터 밴드선택 (Extrema-based Band Selection for Hyperion Data)

  • 한동엽;김대성;김용일
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2006년도 춘계학술발표회 논문집
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    • pp.193-198
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    • 2006
  • Among 242 Hyperion bands, there are 46 bands that contain completely no information and some other bands with various kinds of noise. It is mainly due to the atmosphenc absorption and the low signal-to-noise ratio. The visual inspection for selecting clean and stable bands is a simple practice, but is a manual, inefficient, and subjective Process. Though uncalibrated, overlapping, and all deep water absorption bands are removed, there still exist noisy bands. In this paper, we propose that the extrema ratio be measured for noise estimation and the unsupervised band selection be performed using the Expectation-Maximization algorithm. The Hyperion data were classified into 5 categories according to the image quality by visual inspection, and used as the reference data. The accuracy of the proposed method was compared with signal-to-noise ranking and entropy ranking. As a result, the proposed mettled was effective as preprocessing step for band selection.

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화소간 유사도 측정 기법을 이용한 하이퍼스펙트럴 데이터의 무감독 변화탐지에 관한 연구 (A Study on the Unsupervised Change Detection for Hyperspectral Data Using Similarity Measure Techniques)

  • 김대성;김용일
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2006년도 춘계학술발표회 논문집
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    • pp.243-248
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    • 2006
  • In this paper, we propose the unsupervised change detection algorithm that apply the similarity measure techniques to the hyperspectral image. The general similarity measures including euclidean distance and spectral angle were compared. The spectral similarity scale algorithm for reducing the problems of those techniques was studied and tested with Hyperion data. The thresholds for detecting the change area were estimated through EM(Expectation-Maximization) algorithm. The experimental result shows that the similarity measure techniques and EM algorithm can be applied effectively for the unsupervised change detection of the hyperspectral data.

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자동 캡 세척장치 개발에 관한 연구 (A Study on the Development of Automatic Cap-Washing M/C)

  • 신성우;김대성;이춘만
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.1849-1852
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    • 2005
  • An automatic cap-washing machine is developed for rinse and dry of synthetic resin cap which is used in spring water bottle. This machine should be achieved all processes washing and drying, array, transfer automatically. A cap is washed by an ozonized water and pure water first. Next, a cap is dried by a hot wind drying equipment. In this paper, structural and modal analysis for the cap-washing machine is carried out to check the design criterion of the machine. The analysis is carried out by FEM simulation using the commercial software, CATIA V5. And a fictitious mass properties was used for the analysis of the machine. Finally, the machine performance is shown to be satisfactory.

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소형경량 $1.5{\mu}m$ 대역 발진용 레이저 매질 및 포화 흡수체의 비교분석 (Comparative Analysis on Laser Material and Saturable Absorber for Compact Lightweight $1.5{\mu}m$ Wavelength Radiation)

  • 박도현;오승일;배효욱;김대성
    • 한국군사과학기술학회지
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    • 제7권4호
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    • pp.91-99
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    • 2004
  • Laser materials for eyesafe wavelength generation and Q-switching crystals for short pulse operation were studied and compared with each other. Er,Yb:phosphate glass as a laser material and $Co^{2+}:MgA1_2O_4$ as a saturable absorber were found to be an effective pair for a compact, light-weight passively Q-switched eyesafe laser operation. Simplified rate equation was used to estimate pulse parameters of the diode-pumped passively Q-switched laser.

직동력 고응답 엑츄에이터 구동용 표면부착형 영구자석형 동기 전동기의 슬롯 수에 따른 특성 연구 (Characteristics of SPMSM for electro-hydraulic actuator according to the slot number)

  • 권순오;이병화;이정종;김대성;김범중;홍정표
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.824_825
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    • 2009
  • This paper deals with the characteristics of SPMSM for hydraulic actuator according to the slot number. As a design variable, slot number affects the winding configuration and this leads to the total variation of motor characteristic. Therefore number of slot should be cautiously determined. Three SPMSMs are designed and THD of back emf, cogging torque, and torque ripple are compared. Among three SPMSMs, 36slots with 12 pole is chosen for further development considering motor characteristics and manufacturing.

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경사진 평판에서 2차원 충돌 제트의 유동 특성에 관한 연구 (A Study on the Flow Characteristics of a Two - Dimensional Oblique Plate Impinging Jet)

  • 윤순현;김경문;김대성
    • Journal of Advanced Marine Engineering and Technology
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    • 제21권1호
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    • pp.37-42
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    • 1997
  • Turbulent flow characteristics of a two - dimensional oblique plate impinging jet(OPIJ) were experimentally investigated. The jet mean velocity and turbulent intensity profIles were also measured along the plate. The jet Reynolds numbers(Re, based on the nozzle width)ranged from 10, 000 to 35, 000, the nozzle - to - plate distance(H/B) from 2 to 16, and the oblique angle (a) from 60 to 90 degree. It has been found that the stagnation point shifted toward the minor flow region as the oblique angle decreases and the position of the stagnation point nearly coin¬cided with that of the maximum turbulent intensity.

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미요시근육병 환자에서 밝혀진 Dysferlin 유전자 돌연변이 (Identification of a Dysferlin Gene Mutation in One Patient Showing Clinical Manifestation of Miyoshi Myopathy)

  • 지명구;김남희;김대성;최영철
    • Annals of Clinical Neurophysiology
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    • 제11권2호
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    • pp.59-63
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    • 2009
  • Miyoshi myopathy (MM) is caused by the mutations of dysferlin gene (DYSF), which impairs the function of dysferlin protein causing muscle membrane dysfunction. We report a patient showing the MM phenotype who has a sister with LGMD 2B phenotype, along with the results of the immunohistochemical and molecular analyses of the DYSF gene. Immunohistochemical analysis noted negative immunoreactivity against dysferlin. Direct DNA sequencing of whole exons of DYSF gene revealed heterozygous nonsense mutations (c.610C>T + c.2494C>T). To our knowledge, this is the first reported MM case with this very combination of heterozygous mutations.

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호흡곤란을 초기 증상으로 내원한 근육위축가쪽경화증 환자에서 침근전도검사 후 발생한 기흉 (Pneumothorax Following Needle Electromyography in a Patient with Amyotrophic Lateral Sclerosis Who Presented with Respiartory Failure As an Initial Symptom)

  • 이승안;이현석;김대성
    • Annals of Clinical Neurophysiology
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    • 제10권1호
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    • pp.62-65
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    • 2008
  • We report a patient with amyotrophic lateral sclerosis (ALS) who developed a pneumothorax after needle electromyography (EMG), probably of the intercostal muscles. Needle EMG on intercostal muscles has a high risk of pneumothorax, not only because electromyographers are unfamiliar to its technique, but also due to its close anatomical location to the pleural cavity. In our patient, advanced intercostal muscle atrophy due to disease process would have increased the risk further.

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버스 윈도우 필라 부재의 형상 최적 설계기술 개발 (Development of Optimum Design Technique for Bus Window Pillar Member)

  • 김명한;김대성;임석현;서명원;배동호
    • 한국자동차공학회논문집
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    • 제7권6호
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    • pp.156-164
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    • 1999
  • The body structure of a bus is generally assembled by using various spot welded box sectional members. The shape of window pillar joint is ordinarily built up by T-type member. It has been shown that T-type member has problems like high stress concentrations, low fatigue strength and low structural rigidity. In this study, to solve these problems a new approach to optimize the design of the bus window pillar joint was tried by FEM analysis and experiments. To describe the shape of the gusset connecting the vertical and horizontal members of the T-type window pillar joint B-spline curve was adopted and this curve was optimized . It was found that the new model developed could effectively improve fatigue durability an structural rigidity.

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요배근력 촉정 및 L_5/S_1$ 요추부하 평가에 관한 연구 (A Study on the Measurement of Back Power and the Evaluation of Compression Force at the L_5/S_1$)

  • 양성환;김대성;박범
    • 한국안전학회지
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    • 제12권3호
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    • pp.161-165
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    • 1997
  • Recently, industrial accidents have been getting great damage to an enterprise management directly and indirectly, the industrial injuries of conventional type are decreasing : on the other hand, musculoskeletal injuries are trending to a rapid increase. This shows that most of carrying works have been performing in almost all production process and convey objects, machine equipment and work method. Then, they are made by unfitted design which doesn't consider physical condition of workers, so it causes them to bring about forceful motion. In this paper, it was used NIOSH standard the data of spot. The ergonomic design of machine equipment and the evaluation of biomechanical compression force at theL_5/S_1$and back power, intend to provide the basis which can be applied, compared, and analyzed between before process improvement and after.

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