• 제목/요약/키워드: Local Value

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복잡한 FLIR 영상에서의 소형 표적 탐지 기법 (Small Target Detection Method under Complex FLIR Imagery)

  • 이승익;김주영;김기홍;구본호
    • 한국멀티미디어학회논문지
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    • 제10권4호
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    • pp.432-440
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    • 2007
  • 본 논문에서는 복잡한 배경을 가지는 전방 관측 열상(FLIR; forward looking infrared) 영상에서의 소형 표적 탐지 기법을 제안하였다. 제안한 기법에서는 먼저 이전 프레임과 현재 프레임의 차를 구하여 표적의 움직임 정보를 획득할 뿐만 아니라 시간적으로 발생하는 배경 잡음을 제거한다. 이때 먼 거리에서 다가오는 표적이나 속도가 느린 표적의 경우 차 영상 내에서의 표적의 움직임 정보는 매우 작은 명암도 값을 가진다. 이런 작은 명암도 값을 두드러지게 하여 표적 탐지를 용이하게 하기 위하여 프레임 차 영상에 국부 감마교정을 행한다. 이렇게 표적이 개선된 영상에서 국부적인 통계적인 특성을 이용하여 탐지 지표를 계산한 후 가장 낮은 탐지 지표 값을 탐지하고자하는 표적으로 선정한다. 실험을 통하여 제안한 기법이 표적의 탐지성능이 기존의 탐지기법보다 우수하였음을 확인하였다.

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층상구조에서 지진파 전파경로를 고려하여 수정된 경험 Green 함수를 이용한 지반운동 모사 (Site-Specific Ground Motions based on Empirical Green`s Function modified for the Path Effects in Layered Media)

  • 조남대;박창업
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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    • pp.19-27
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    • 2001
  • Seismic parameters fur computation of ground motions in Southern Korea are obtained from recently recorded data, and site-independent regional and site-dependent local strong ground motions are predicted using efficient computational techniques. For the computation of ground motions, we devised an efficient procedure to compute site-independent $x_{q}$ and dependent $x_{s}$ values separately. The first step of this procedure is to use the coda normalization method far computation of site independent Q or corresponding $x_{q}$ value. The next step is the computation of $x_{s}$, values fur each site separately using the given $x_{q}$ value. For computation of ground motions the empirical Green's function (EGF) is modified to account fur the depth and distance variations of subevents on a finite fault plane using the theoritical Green's function. It is computed using wavenumber integration technique in layered media. The site dependent ground motions at seismic stations in southeastern local area were properly simulated using the modified empirical Green's function method in layered medium. The proposed method and procedures fur estimation of site dependent seismic parameters and ground motions could be efficiently used in the low and moderate seismicity regions.ons.s.ons.

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곡선부에서 차륜 마모 저감을 위한 차륜답면 형상 설계 (Design of Wheel Profile to Reduce Wear of Railway Wheel)

  • 최하영;이동형;송창용;이종수
    • 한국정밀공학회지
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    • 제29권6호
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    • pp.607-612
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    • 2012
  • The wear problem of wheel flange occurs at sharp curves of rail. This paper proposes a procedure for optimum design of a wheel profile wherein flange wear is reduced by improving an interaction between wheel and rail. Application of optimization method to design problem mainly depends on characteristics of design space. This paper compared local optimization method with global optimization according to sensitivity value of objective function for design variables to find out which optimization method is appropriable to minimize wear of wheel flange. Wheel profile is created by a piecewise cubic Hermite interpolating polynomial and dynamic performances are analyzed by a railway dynamic analysis program, VAMPIRE. From the optimization results, it is verified that the global optimization method such as genetic algorithm is more suitable to wheel profile optimization than the local optimization of SQP (Sequential Quadratic Programming) in case of considering the lack of empirical knowledge for initial design value.

Levels of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans in Soil and Pine needle near Industry Complex in Changwon City

  • Kim Sang-Jo;Kim Sung-Yong;Ok Gon
    • 한국환경과학회지
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    • 제14권7호
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    • pp.629-637
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    • 2005
  • Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were investigated in soil and pine needle samples taken from 16 sites of industrial and residential areas in Changwon, Korea to assess their distribution levels and to suggest the influence of industrial activities, PCDDs/DFs levels in the soil samples ranged from 0.57 to 20.79 pg I-TEQ/g dry weight with a mean value of 4.20 pg I-TEQ/g dry weight. PCDDs/DFs levels in the pine needle samples ranged from 0.39 to 8.75 pg I-TEQ/g dry weight with a mean value of 4.09 pg I-TEQ/g dry weight. In both soil and pine needle samples, the PCDDs/DFs concentrations in the industrial area sites were higher than those in the residential area sites. Homologue profiles in pine needle samples showed different patterns compared with soil samples. Based on the results of principal component analysis (PCA), it was confirmed that pine needles reflected a direct influence from local potential sources of PCDDs/DFs, showing a much higher degree of reflection than in soils. Pine needles are very useful as an indicator for monitoring or estimating the contamination of PCDDs/DFs in other areas which have been impacted by point pollution sources.

올린 도서관 현상설계에서 나타난 근대건축의 공간적 특성에 관한 연구 - 장소적 질서와 형태적 상징을 중심으로 - (A Study on the Spatial Characteristics of Modern Architecture found from the Olin Library Competition - Focused on the Local Order and Morphological symbols -)

  • 임종엽;김윤겸
    • 교육시설 논문지
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    • 제22권4호
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    • pp.15-25
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    • 2015
  • The Olin Library in St. Louis was an important design competition for the United States in the 1950's, the rear of America's modern architecture. The participants of this competition were a variety of representative architects and groups of its time. With the library's functional rationality, the Olin Library competition was legible of the aspects of modern architectural flow. The competition required two demands. The first demand was absolute importance in character definition of place, which was to satisfy the site conditions approached from campus design. Secondly was related to interpretation of morphological symbolism in an architectural matter. The experiments of American modern architecture started to change its ideal goal gradually ; accommodating the altering public's code, at the same time, maintaining the original modern value was the reason to changing the ideal goal. As a turning point, the Olin Library should be understood as an important work, which divulged the value change of architectural interpretation.

Energy-Efficient Adaptive Dynamic Sensor Scheduling for Target Monitoring in Wireless Sensor Networks

  • Zhang, Jian;Wu, Cheng-Dong;Zhang, Yun-Zhou;Ji, Peng
    • ETRI Journal
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    • 제33권6호
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    • pp.857-863
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    • 2011
  • Due to uncertainties in target motion and randomness of deployed sensor nodes, the problem of imbalance of energy consumption arises from sensor scheduling. This paper presents an energy-efficient adaptive sensor scheduling for a target monitoring algorithm in a local monitoring region of wireless sensor networks. Owing to excessive scheduling of an individual node, one node with a high value generated by a decision function is preferentially selected as a tasking node to balance the local energy consumption of a dynamic clustering, and the node with the highest value is chosen as the cluster head. Others with lower ones are in reserve. In addition, an optimization problem is derived to satisfy the problem of sensor scheduling subject to the joint detection probability for tasking sensors. Particles of the target in particle filter algorithm are resampled for a higher tracking accuracy. Simulation results show this algorithm can improve the required tracking accuracy, and nodes are efficiently scheduled. Hence, there is a 41.67% savings in energy consumption.

등각사상과 평균값좌표계를 이용한 정점 법선벡터 계산법 (Vertex Normal Computation using Conformal Mapping and Mean Value Coordinates)

  • 김형석;김호숙
    • 한국정보통신학회논문지
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    • 제13권3호
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    • pp.451-457
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    • 2009
  • 컴퓨터그래픽스에서 다루어지는 대부분의 물체들은 메쉬 형태로 표현된다. 보다 다양한 형태로의 변형이나 현실감 있는 렌더링을 얻기 위해서는 정점에서의 올바른 법선벡터 계산이 필수적이다. 이에 대한 기존 연구들은 정점의 기하학적 특성을 단순하게 반영하는 가중치를 사용하였다. 본 논문에서는 국지적 기하학 특성을 종합적으로 반영하는 등각사상과 이웃 정점과의 상호관계를 연속적으로 표현할 수 있는 중간값 좌표계를 사용하는 방법을 제안한다. 논문에서 제시된 방법이 기존 다른 방법에 비해서 보다 정확한 법선벡터를 계산할 수 있음을 실험을 통해서 알 수 있다.

충북 u-Health 산업의 국제적 마케팅전략 연구 (International Marketing Strategies for Chungbuk's U-Health Industry)

  • 하대용;오상영
    • 한국산학기술학회논문지
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    • 제8권6호
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    • pp.1655-1661
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    • 2007
  • 최근 유비쿼터스 기술을 응용하여 다양한 산업이 등장하고 있다. 특히 미래 산업으로 관심을 끌고 있는 인류의 건강 관련은 유비쿼터스 시스템과 융합되면서 중요한 산업으로 등장하고 있다. 이를 u-Health산업이라 한다. 국내에서는 지방자치제도에 따라 지역 여건에 맞는 고부가가치 산업을 창출하고자 노력한다. 본 연구는 충북 지역의 특화 산업으로서 u-Health 산업 분야를 가정하고, 제품의 효율적 시장 진입을 위한 마케팅 전략을 연구하였다. 마케팅전략으로는 세계 시장을 대상으로 한 STP 전략를 제시하였다. 전략 구상의 기준은 세계 주요 선진국의 노령화 지수 및 모딜리아니의 생애주기가설을 토대로 연구하였다. 마지막으로 충북 지역에 u-Health 제품 출시가 되지 않은 것을 감안하여 제품 출시 후 활용할 마케팅 믹스 전략 방안을 제시하였다.

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Using Huff Model for Predicting the Potential Chiness Retail Market

  • Su, Shuai;Youn, Myoung-Kil
    • Asian Journal of Business Environment
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    • 제1권1호
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    • pp.9-12
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    • 2011
  • This study aimed to predict retail sales of local markets in Jinan city of China with the Huff model. Using the Huff Model, we examined whether the predicted retail sales of local markets may be different in Jinan, China, from the department stores, supermarkets, shopping centers/shopping malls, and home appliance stores. The probability that a customer shops at location depends upon the store size and the travel time factors calculated by the Huff Model. We found that the predictedretail sales of shopping malls have a greater value than others. People who live in a mid-sized city may have easier access to any stores within the city boundary than people in metropolitan areas. Therefore, people in a mid-sized city are more sensitive to store size, because a bigger store size means greater opportunities, incentivizing consumers to travel further to competing stores after passing by nearer, smaller stores. This study has some limitations. First, the data is somewhat restricted in that the subject stores do not represent all of the stores in Jinan. Second, we cannot compare the estimated market share of the stores and the actual sales data. It is further suggested in this study that more databases be developed throughout such East Asian countries as Korea and Japan and that a different parameter λ value in the Huff Model be utilized for mid-sized cities.

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R-290, R-600a의 수평 이중관형 열교환기내 증발 특성 (Evaporating Heat Transfer Characteristics of R-290, R-600a Inside Horizontal Double Pipe Heat Exchangers)

  • 홍진우;노건상;권옥배;박기원;오후규
    • 설비공학논문집
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    • 제12권3호
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    • pp.309-314
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    • 2000
  • Experimental results for heat transfer characteristics of natural refrigerants R-290, R-600a and HCFC refrigerant R-22 during evaporating inside horizontal double pipe heat exchangers are presented. The experimental apparatus is basically a vapour heat pump system, composed of a compressor, a condenser, expansion devices, a evaporator, and some other peripheral devices. The test sections were horizontal double pipe heat exchangers, which were a pair of smoothed tube, having 10.07 mm ID, 12.07 mm OD, and grooved inner fin tube, having 12.70 mm OD, 0.25 mm fin height, and 75 fins. The local evaporating heat transfer coefficients of natural refrigerants were not much affected with the mass velocity than R-22 and it could be interpreted that the local evaporating heat transfer coefficients of R-22 were increased more than those of R-290, R-600a according to the increment of mass velocity. Moreover, the maximum increment of the heat transfer coefficient was found in R-290. The average heat transfer coefficient was obtained the maximum value in R-290 and the minimum value in R-22. It reveals that the natural refrigerant can be used as a substitute for R-22. In the grooved inner fin tube, 70% of the increment of the heat transfer coefficient was obtained compared to the smoothed tube.

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