• Title/Summary/Keyword: 초기곡선

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A Conceptual Framework of IoT Case Study (IoT 사례분석을 위한 개념적 틀 제시)

  • Jeon, Ka Young;Lee, Jang Hyuk;Oh, Jungsuk
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.10 no.3
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    • pp.123-131
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    • 2015
  • With a prospective of rapid deployment of IOT, a systematic approach to derive a business strategy for various possible scenarios of IOT applications is in great demand. In this paper, a conceptual framework that can be utilized for the purpose of assessing the market potential and of setting up an initial business strategy for IOT deployment is suggested. The framework consists of utilization of well-known value curve analysis, ecosystem analysis and house of quality tools. The value curve analysis is utilized to identify value-enhancing components of consumers as well as relative strengths of suppliers. The ecosystem analysis is used to identify relevant players of the supply chain and their mutual relationships. The house of quality is suitable for developing the initial business strategy of the supplier by converting consumer requirements identified by value curve analysis into technical requirements for the supplier. In this paper, we applied our proposed framework to two services that have high potentiality of being benefited by IOT: car-sharing service and telehealth service.

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Automatic Identification of the Lumen Border in Intravascular Ultrasound Images (혈관 내 초음파 영상에서 내강 경계면 자동 분할)

  • Park, Jun-Oh;Ko, Byoung-Chul;Park, Hee-Jun;Nam, Jae-Yeal
    • The KIPS Transactions:PartB
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    • v.19B no.3
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    • pp.201-208
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    • 2012
  • Accurately segmenting lumen border in intravascular ultrasound images (IVUS) is very important to study vascular wall architecture for diagnosis of the cardiovascular diseases. After each of IVUS image is transformed to a polar coordinated image, initial points are detected using wavelet transform. Then, lumen border is initialized as the set of important points using non parametric probability density function and smoothing function by removing outlier initial points occurred by noises and artifacts. Finally, polynomial curve fitting is applied to obtain real lumen border using filtered important points. The evaluation of proposed method was performed with related method and the proposed method produced accurate lumen contour detection when compared to another method in most types of IVUS images.

Suspended Time Dependent Meat Weight Increase of Oysters, Crassostrea gigas, in Pukman Bay, Korea (북만의 양식 참굴, Crassostrea gigas의 수하시기에 따른 육중량 변화)

  • 정우건;조상만;조창환
    • The Korean Journal of Malacology
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    • v.15 no.1
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    • pp.41-47
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    • 1999
  • From September 1994 to April 1996, we observed the suspending time dependant meat increase (dry weight) for oysters at Pukman Bay in Korea. The oysters which suspended in September increased to 5 g in meat weight (dry weight) by January. Ones in June increased rapidly but lessened during summer and this stagnation of meat increase extended to autumn. It took long time to compensate for the loss of meat weight owing to spawning. Oysters suspended in July or August showed low growth or stagnation due to the high water temperature and spawning activities after suspending. However, meat weight showed sudden increasement after December and achieved 5 g at the late farm period. The meat increase of oysters suspended in October or November was very slow during entire growing period. Most of them did not achieved 5 g during farm period. The negative correlation was observed between meat growth and water temperature in September. Also, there was a high correlation between meat growth and chlorophyll-a. It was believed that deficiency of food organisms in the water column lead slow growth in terms of meat growth, particularly right after transplanting seed oysters to the farm. Our study suggests that proper time for transplanting oysters is between August and mid-September. However, the data indicate that good growth of oysters is depending upon amount of food available in the water column.

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Facial Contour Extraction in PC Camera Images using Active Contour Models (동적 윤곽선 모델을 이용한 PC 카메라 영상에서의 얼굴 윤곽선 추출)

  • Kim Young-Won;Jun Byung-Hwan
    • Proceedings of the Korea Contents Association Conference
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    • 2005.11a
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    • pp.633-638
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    • 2005
  • The extraction of a face is a very important part for human interface, biometrics and security. In this paper, we applies DCM(Dilation of Color and Motion) filter and Active Contour Models to extract facial outline. First, DCM filter is made by applying morphology dilation to the combination of facial color image and differential image applied by dilation previously. This filter is used to remove complex background and to detect facial outline. Because Active Contour Models receive a large effect according to initial curves, we calculate rotational degree using geometric ratio of face, eyes and mouth. We use edgeness and intensity as an image energy, in order to extract outline in the area of weak edge. We acquire various head-pose images with both eyes from five persons in inner space with complex background. As an experimental result with total 125 images gathered by 25 per person, it shows that average extraction rate of facial outline is 98.1% and average processing time is 0.2sec.

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Fracture Behavior of Concrete and Equivalent Crack Length Theory (콘크리트의 파괴거동규명과 등가균열(等價龜裂)길이 이론확립(理論確立)에 관한 연구)

  • Oh, Byung Hwan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.7 no.2
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    • pp.59-68
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    • 1987
  • Several series of fracture tests were conducted to explore the fracture characteristics and to determine the fracture energy of concrete. A stable three-point bend test was employed to generate the load-deflection curves. The fracture energy may then be calculated from the area under the complete load-deflection curve. The initial notch-to-beam depth ratio (${\alpha}_0$/H) was varied from zero to 0.6. The prediction formula for the fracture energy of concrete is also derived and is found to depend on the tensile strength and aggregate size. The proposed fracture energy formula can be used for the fracture analysis of concrete structures. The present study also devises an equivalent crack length concept to predict the maximum failure loads of concrete beams. A simple formula for the equivalent crack length is proposed.

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Evaluation of Reliability Hydrologic Investigation in Imha Basin Using Distributed Model (GIS 기반 분포형 유출모형을 이용한 임하댐 유역의 수문조사 신뢰도 검증)

  • Kim, Myung-Hyun;An, Hyung-Mo;Kim, Chang-Soon;Lee, Myung-Hyun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2010.05a
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    • pp.1104-1108
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    • 2010
  • 최근 수자원의 효율적인 배분을 위한 수자원관리의 중요성에 대한 인식과 하천의 환경적 기능에 대한 사회적 요구 증대로 수자원 기초조사에 의해 수집되어진 자료의 활용빈도가 다양한 분야에서 증가하고, 높은 신뢰도와 정확도를 요구하고 있다. 개발된 수위-유량 관계식의 신뢰도 검증은 일반적으로 지점별 수위-유량 관계식과 수위자료에 의해 산정된 유하량을 유역의 면적평균 강우량을 이용하여 산정한 유출률과 비교 분석하는 수문학적 방법에 의해 이루어지고 있는 실정이다. 최근에는 공간적인 비균질성을 고려하여 유출과정에서 운동역학적인 이론을 기반으로 물의 흐름을 수리학적으로 추적해 나가는 물리적 기반의 분포형 유출모형의 활용도가 높아지고 있음에 따라 본 연구에서는 낙동강수계 임하댐유역을 대상으로 물리적 기반의 분포형 모형인 $Vflo^{TM}$을 적용하여 유출량을 산정하고, K-water에서 수자원 환경기초조사 성과로 개발된 임하댐 상류 영양 수위관측소의 수위-유량 관계 곡선식을 이용하여 산정된 유출량과 비교함으로써 수자원기초조사 성과의 신뢰도를 검증하였다. 분포형 유출모형 적용에 필요한 매개변수 추출을 위해 GIS 기법을 이용하여 DEM, 토지피복도, 토양도에서 $Vflo^{TM}$의 입력인자인 경사도, 흐름방향, 조도계수, 수리전도도, 유효공극률, 토양심도를 추출 산정하였으며, 임하댐 유역의 8개 우량관측소 시우량자료를 이용하여 강우의 공간적인 통계 특성을 잘 반영하는 크리깅(Kriging) 기법에 의한 분포형 강우를 생성하였다. 또한, 본 모형을 통해 검증된 초기함수조건 등의 유역의 특성을 이용한 단기유량예측을 통하여 홍수량 예측 및 수문조사 효율성 향상에 매우 중요한 역할을 할 것으로 기대된다.

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Experimental Study for Fracture Characteristic of New Building Materials with Recycled Ash (석탄회 재활용 건설신소재 개발을 위한 파괴특성에 관한 실험적 연구)

  • Jo Byung-Wan;Park Jong-Bin;Keo Ja-Gab
    • Journal of the Korea Concrete Institute
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    • v.17 no.2 s.86
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    • pp.255-261
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    • 2005
  • Immense quantities of coal combustion by-products are produced every year, and only a small fraction of them are currently utilized. The purpose of this study is to investigate reused techniques of coal ash in the construction field, which may contribute to the savings of building materials and conservation of environment. From the results of the compressive strength test, the elastic modulus was experimentally proposed. Also, based on the three- point-bending test, the fracture parameters - notch sensitivity, fracture energy, and initial compliance were experimentally proposed. As a result, the strength and fracture characteristics were lower than those of concrete or mortar. Also, the study showed that the deflection at a fracture decreased as the age increased and as the notch depth rate decreased. However, it was judged that its use as a building material could be expected if further research is carried out.

Automatic Brain Segmentation for 3D Visualization and Analysis of MR Image Sets (MR영상의 3차원 가시화 및 분석을 위한 뇌영역의 자동 분할)

  • Kim, Tae-Woo
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.2
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    • pp.542-551
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    • 2000
  • In this paper, a novel technique is presented for automatic brain region segmentation in single channel MR image data sets for 3D visualization and analysis. The method detects brain contours in 2D and 3D processing of four steps. The first and the second make a head mask and an initial brain mask by automatic thresholding using a curve fitting technique. The stage 3 reconstructs 3D volume of the initial brain mask by cubic interpolation and generates an intermediate brain mask using morphological operation and labeling of connected components. In the final step, the brain mask is refined by automatic thresholding using curve fitting. This algorithm is useful for fully automatic brain region segmentation of T1-weighted, T2-weighted, PD-weighted, SPGR MRI data sets without considering slice direction and covering a whole volume of a brain. In the experiments, the algorithm was applied to 20 sets of MR images and showed over 0.97 in comparison with manual drawing in similarity index.

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Rotation and Scale Invariant Face Detection Using Log-polar Mapping and Face Features (Log-polar변환과 얼굴특징추출을 이용한 크기 및 회전불변 얼굴인식)

  • Go Gi-Young;Kim Doo-Young
    • Journal of the Institute of Convergence Signal Processing
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    • v.6 no.1
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    • pp.15-22
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    • 2005
  • In this paper, we propose a face recognition system by using the CCD color image. We first get the face candidate image by using YCbCr color model and adaptive skin color information. And we use it initial curve of active contour model to extract face region. We use the Eye map and mouth map using color information for extracting facial feature from the face image. To obtain center point of Log-polar image, we use extracted facial feature from the face image. In order to obtain feature vectors, we use extracted coefficients from DCT and wavelet transform. To show the validity of the proposed method, we performed a face recognition using neural network with BP learning algorithm. Experimental results show that the proposed method is robuster with higher recogntion rate than the conventional method for the rotation and scale variant.

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Development of Estimation Algorithm of Latent Ability and Item Parameters in IRT (문항반응이론에서 피험자 능력 및 문항모수 추정 알고리즘 개발)

  • Choi, Hang-Seok;Cha, Kyung-Joon;Kim, Sung-Hoon;Park, Chung;Park, Young-Sun
    • Communications for Statistical Applications and Methods
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    • v.15 no.3
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    • pp.465-481
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    • 2008
  • Item response theory(IRT) estimates latent ability of a subject based on the property of item and item parameters using item characteristics curve(ICC) of each item case. The initial value and another problems occurs when we try to estimate item parameters of IRT(e.g. the maximum likelihood estimate). Thus, we propose the asymptotic approximation method(AAM) to solve the above mentioned problems. We notice that the proposed method can be thought as an alternative to estimate item parameters when we have small size of data or need to estimate items with local fluctuations. We developed 'Any Assess' and tested reliability of the system result by simulating a practical use possibility.