• Title/Summary/Keyword: Neighborhood method

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Development of Adaptive Spatial Filter to Improve Noise Characteristics of PET Images (PET 영상의 잡음개선을 위한 적응적 공간 필터 개발)

  • Woo, S. K.;Choi, Y.;Im, K. C.;Song, T. Y.;Jung, J. H.;Lee, K. H.;Kim, S. E.;Choe, Y. S.;Park, C. C.;Kim, B. T.
    • Journal of Biomedical Engineering Research
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    • v.23 no.3
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    • pp.253-261
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    • 2002
  • A spatially adaptive falter was formulated to imrove PET image qualify and the Performance of the filter was evaluated using simulation and phantom and human PET studies. In the proposed filter. if a pixel was identified as the edge Pixel, the Pixel value was Preserved. Otherwise a Pixel was replaced by the mean of the pixel values weighted by 2:7: 2. A Pixel was identified as the edge Pixel. if it satisfies the following conditions : the number of ADs (absolute difference between center and neighborhood pixels) which is smaller than THl (($pix_max{\times}0.1/log_2(NPM)$, NPM : mean of 6 neighborhood pixels excluding minimum and maximum) is 8-k and the number of ADs which is lager than TH2 ($NPM{\times}0.1$) is k. where k : 2, 3, …, 6. The results of this study demonstrate the superior performance of the Proposed titter compared to Gaussian fitter, weight median filter and subset averaged median filter. The proposed tittering method is simple but effective in increasing uniformity and contrast with minimal degradation of spatial resolution of PET images and thus. is expected to Provide improved diagnositc quality PET images .

Spatial Analysis of the Difference between Real Crime and Fear of Crime (도시내 범죄발생과 범죄 두려움 위치의 공간적 차이 분석)

  • Heo, Sun-Young;Moon, Tae-Heon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.4
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    • pp.194-207
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    • 2011
  • This study tries to find the possibility to prevent crime by improving urban spatial environment through the analysis of spatial environment property that mutually coincides or differs by comparing the place where crime actually occurs and the place where citizen is afraid of crime. The method of study is as follows. First, the ontents scope and method of study was established by theoretic investigation of case study related to crime. Second, as crime cannot be prevented by police power only, CPSCP(Citizen Participation System for Crime Prevention) was developed so that all citizen can cooperatively participate in the crime prevention anytime and anywhere. Third, the data on the place where people feel fear in the region was collected by directly indicating the place where citizen is afraid of crime in the space by utilizing CPSCP. Fourth, the place where crime actually occurs and the place where citizen is afraid of crime are redundantly analyzed for comparative analysis of 2 places. The result shows that environmental design improving physical environment of urban space is necessary to prevent crime and to eliminate the fear of crime. The CPSCP developed by this study which will be advanced to U-crime prevention system will contribute to making citizen's own neighborhood a smart safety city autonomously.

Infrared Image Sharpness Enhancement Method Using Super-resolution Based on Adaptive Dynamic Range Coding and Fusion with Visible Image (적외선 영상 선명도 개선을 위한 ADRC 기반 초고해상도 기법 및 가시광 영상과의 융합 기법)

  • Kim, Yong Jun;Song, Byung Cheol
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.11
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    • pp.73-81
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    • 2016
  • In general, infrared images have less sharpness and image details than visible images. So, the prior image upscaling methods are not effective in the infrared images. In order to solve this problem, this paper proposes an algorithm which initially up-scales an input infrared (IR) image by using adaptive dynamic range encoding (ADRC)-based super-resolution (SR) method, and then fuses the result with the corresponding visible images. The proposed algorithm consists of a up-scaling phase and a fusion phase. First, an input IR image is up-scaled by the proposed ADRC-based SR algorithm. In the dictionary learning stage of this up-scaling phase, so-called 'pre-emphasis' processing is applied to training-purpose high-resolution images, hence better sharpness is achieved. In the following fusion phase, high-frequency information is extracted from the visible image corresponding to the IR image, and it is adaptively weighted according to the complexity of the IR image. Finally, a up-scaled IR image is obtained by adding the processed high-frequency information to the up-scaled IR image. The experimental results show than the proposed algorithm provides better results than the state-of-the-art SR, i.e., anchored neighborhood regression (A+) algorithm. For example, in terms of just noticeable blur (JNB), the proposed algorithm shows higher value by 0.2184 than the A+. Also, the proposed algorithm outperforms the previous works even in terms of subjective visual quality.

Analysis of Land Cover Characteristics with Object-Based Classification Method - Focusing on the DMZ in Inje-gun, Gangwon-do - (객체기반 분류기법을 이용한 토지피복 특성분석 - 강원도 인제군의 DMZ지역 일원을 대상으로 -)

  • Na, Hyun-Sup;Lee, Jung-Soo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.2
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    • pp.121-135
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    • 2014
  • Object-based classification methods provide a valid alternative to traditional pixel-based methods. This study reports the results of an object-based classification to examine land cover in the demilitarized zones(DMZs) of Inje-gun. We used land cover classes(7 classes for main category and 13 classes for sub-category) selected from the criteria by Korea Ministry of Environment. The average and standard deviation of the spectrum values, and homogeneity of GLCM were chosen to map land cover types in an hierarchical approach using the nearest neighborhood method. We then identified the distributional characteristics of land cover by considering 3 topographic characteristics (altitude, slope gradient, distance from the Southern Limited Line(SLL)) within the DMZs. The results showed that scale 72, shape 0.2, color 0.8, compactness 0.5 and smoothness 0.5 were the optimum weight values while scale, shape and color were most influenced parameters in image segmentation. The forests (92%) were main land cover type in the DMZs; the grassland(5%), the urban area (2%) and the forests (broadleaf forest: 44%, mixed forest: 42%, coniferous forest: 6%) also occupied mostly in land cover classes for sub-category. The results also showed that facilities and roads had higher density within 2 km from the SLL, while paddy, field and bare land were distributed largely outside 6 km from the SLL. In addition, there was apparent distinction in land cover by topographic characteristics. The forest had higher density at above altitude 600m and above slope gradient $30^{\circ}$ while agriculture, bare land and grass land were distributed mainly at below altitude 600m and below slope gradient $30^{\circ}$.

Analysis on the Stress of Hydraulic Cylinder for Large Vessel by Boundary Element Method (대형선박용 유압실린더에서 경제요소법을 이용한 응력해석)

  • 김옥삼
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.31 no.4
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    • pp.423-434
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    • 1995
  • It was used boundary element method(BEM) and analysed axisymmetric problem to solve hydraulic cylinder for large vessel acting uniform internal pressure(25N/m super(2)) within elastic limit. This paper was utilized the carbon steel tubes for machine structural purposed model, inner radius was 150mm and outer radius was 250mm, axial length was semi-infinite and the isoparametric element was used. The important results obtained in this study were summarized as follows. Radial, tangential and shearing stress occured the maximum stresses(48, -20 and 34MPa) at the inner radius and the minimum stresses(32, -4 and 18MPa) at the outer radius of the hydraulic cylinder for large vessel. But negative signs have meaning compressive stress and stress diminution ratio was about 0.15MPa/mm. The use of isoparametric element raised accuracy and the increment of input data lessened the error in internal point but computer run-time was increased. The double node was improved the internal solutions to settle discontinuity at corner and the double exponential formula lessened error of stress value at boundary neighborhood. And then coincidence between the analytical and exact results is found to be fairly good, showing that the proposed analytical by BEM is reliable.

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A study of Improvement on the Road Drainage Poor Site (도로배수 취약구간의 개선방안에 대한 연구)

  • Lee, Man-Seok;Kim, Heung-Rae;Lee, Kyung-Ha;Kang, Min-Soo;Song, Min-Tae
    • International Journal of Highway Engineering
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    • v.13 no.2
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    • pp.125-131
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    • 2011
  • This research aims to investigate the cause of the occurrence of a weak road drainage section scientifically and specifically through a site survey for a poorly drained section occurring due to rainfalls during road operation. This paper deeply reviewed the existing research results and current situation data on the poorly drained sections accumulated in Korea Expressway Corporation in order to investigate the cause of the occurrence of a weak road drainage section, and deeply verified and analyzed the weak sections for the road surface drainage facilities and the other road drainage facilities by visiting the expressway controlled by the 6 local headquarters and 33 branches of Korea Expressway Corporation. As a result of site surveys for the weak road drainage sections, i) in a road surface section, occurrence of ponding in the road shoulder pavement due to slope changes, bad collection of water in the collecting well at a median strip, shortage of road shoulder dike height, and inferior construction, etc. was analyzed to be the main cause of the occurrence of poorly drained sections, and ii) in a road neighborhood section, the occurrence of pavement height difference in a main road and shoulder section due to inferior ditches on a slope and the bad drain age at the inlet and outlet of a culvert due to soil deposits, debris, etc. were analyzed to be the main cause of the occurrence of weak sections. Proposed as a plan to improve the poorly drainage section of road were i)calculation of capacity through material changes at the ditch, enhancement of vertical sections and hydraulic analysis in terms of construction and other aspects, ii)derivation of a combined slope considering a slope and a vertical linearity and maintenance of proper distance between drainage structures in a vertical concave section in terms of geometrical structure, and iii)calculation of the drainage facility installation interval using a minutely rainfall intensity formula and a non-uniform flow analysis technique in terms of hydraulics and hydrologics and prompt removal of rainfalls from the road surface according to a linear drainage method.

Development of Family Nursing Phenomena in Korea by Retrospective Method of ICNP (ICNP의 후향적 개발방법에 의한 한국가족현상)

  • Yun, Sun-Nyeong;Kim, Hyeon-Suk;Gwon, Yeong-Suk;Park, Gyeong-Min;Kim, Hwa-Jung;Lee, Ji-Hyeon;Go, Yeong-Ae;So, Ae-Yeong;Yang, Sun-Ok;Jeon, Gyeong-Ja;Lee, In-Suk;Kim, Yeom-Im;Kim, Eun-Hui
    • Research in Community and Public Health Nursing
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    • v.10 no.2
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    • pp.275-290
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    • 1999
  • The Objectives of this study were to identify family nursing phenomena at the community in Korea and to contribute to build up family domain of International Classification for Nursing Practice. The method of this study was used retrospective one among three methods to develop ICNP during the period from April 1997 to June 1999. The procedure was to choose nursing phenomena using preliminary terms(stepl) from the reports on family nursing care of the nursing students of 5 junior colleges of nursing and 5 colleges of nursing. The study group members identified 3 common family nursing phenomena with 5 characteristics related to each phenomenon. In order to consensus the appropriate characteristics of a phenomenon(step2), 17 study group members had regrouped nursing phenomena and scored its characteristics 5 times. The essential characteristics of each family phenomenon were selected above 3.5 mean score from related characteristics(step 3). Finally, 17 phenomena were named preferred terms such as following, that was selected after investigated preliminary terms(step4). Family nursing phenomena in Korea are named as Lack of family interaction in community. Social isolation. Lack of social support system in community. Disturbance in parent role, Disturbance in marital role, Dissatisfaction of sexual life, Disturbance in family communication, Inappropriate family coping, Lack of family intimacy, Inappropriate family power structure, Family violence. Unhealthy life style. Deficit of financial management skill and support. Inadequate care a sick member. Insecure safety and hygiene in neighborhood, Inadequate home-sanitation. Inadequate home-making. Family nursing phenomena in Korea were partially confirmed family architecture of ICNP, Beta version. by this study. Further study on Family nursing phenomena in Korea will be required to support evidence through literature review of nursing classifications or field studies.

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A Critical Assessment of the Economical Value of Road on Housing Prices Using Contingent Valuation Method - focus on the road construction plan of 47th of Suwon si - (조건부가치추정법을 이용한 도로의 경제가치 추정에 관한 실증적 연구 - 수원시 47번 도로건설계획을 중심으로)

  • Park, Ki-Hak
    • Environmental and Resource Economics Review
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    • v.21 no.4
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    • pp.999-1024
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    • 2012
  • The Purpose of this study was to assess the willingness to pay(WTP) for the new road construction plan(slip road of urban highway which was advertising extensively to reduce the time to the core of metropolitan area) on housing prices using contingent valuation method(CVM). And this study was an empirical study which was based on the consciousness of residents whose apartment was within the Suwon Si's new plan of 47th road construction zone. In this study, it was revealed that the resident's WTP for the plan of new road construction which was built on the neighborhood of apartment was within the 10 percent of housing prices that was similar to the standard declared price of MLTM(Ministry of Land, Transport and Maritime Affairs). And also revealed that the difference of sale prices of real estate company was 24 percent. The statistical assessment results show that both the resident's characteristic variables such as gender, incomes, size of apartment and the accessability variables such as distance to parks, schools, department stores, living facilities were positive effects on the prices of apartments significantly. Finally, the house has depreciated than that of MLTM and WTO since torpedoed the road construction plan. These results imply that, we have to take capital appreciation of the property into account due to road construction since the accessibility was very significantly positive internal effects on the apartment housing prices.

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Simulation Study on E-commerce Recommender System by Use of LSI Method (LSI 기법을 이용한 전자상거래 추천자 시스템의 시뮬레이션 분석)

  • Kwon, Chi-Myung
    • Journal of the Korea Society for Simulation
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    • v.15 no.3
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    • pp.23-30
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    • 2006
  • A recommender system for E-commerce site receives information from customers about which products they are interested in, and recommends products that are likely to fit their needs. In this paper, we investigate several methods for large-scale product purchase data for the purpose of producing useful recommendations to customers. We apply the traditional data mining techniques of cluster analysis and collaborative filtering(CF), and CF with reduction of product-dimensionality by use of latent semantic indexing(LSI). If reduced product-dimensionality obtained from LSI shows a similar latent trend of customers for buying products to that based on original customer-product purchase data, we expect less computational effort for obtaining the nearest-neighbor for target customer may improve the efficiency of recommendation performance. From simulation experiments on synthetic customer-product purchase data, CF-based method with reduction of product-dimensionality presents a better performance than the traditional CF methods with respect to the recall, precision and F1 measure. In general, the recommendation quality increases as the size of the neighborhood increases. However, our simulation results shows that, after a certain point, the improvement gain diminish. Also we find, as a number of products of recommendation increases, the precision becomes worse, but the improvement gain of recall is relatively small after a certain point. We consider these informations may be useful in applying recommender system.

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Pattern Recognition Improvement of an Ultrasonic Sensor System Using Neuro-Fuzzy Signal Processing (초음파센서 시스템의 패턴인식 개선을 위한 뉴로퍼지 신호처리)

  • Na, Seung-You;Park, Min-Sang
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.12
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    • pp.17-26
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    • 1998
  • Ultrasonic sensors are widely used in various applications due to advantages of low cost, simplicity in construction, mechanical robustness, and little environmental restriction in usage. But for the application of object recognition, ultrasonic sensors exhibit several shortcomings of poor directionality which results in low spatial resolution of objects, and specularity which gives frequent erroneous range readings. The time-of-flight(TOF) method generally used for distance measurement can not distinguish small object patterns of plane, corner or edge. To resolve the problem, an increased number of the sensors in the forms of a linear array or 2-dimensional array of the sensors has been used. Also better resolution has been obtained by shifting the array in several steps using mechanical actuators. Also simple patterns are classified based on analyzing signal reflections. In this paper we propose a method of a sensor array system with improved capability in pattern distinction using electronic circuits accompanying the sensor array, and intelligent algorithm based on neuro-fuzzy processing of data fusion. The circuit changes transmitter output voltages of array elements in several steps. A set of different return signals from neighborhood sensors is manipulated to provide enhanced pattern recognition in the aspects of inclination angle, size and shift as well as distance of objects. The results show improved resolution of the measurements for smaller targets.

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