• Computers and Concrete
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• 제33권4호
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• pp.425-443
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• 2024

Floods are among the most common natural hazards in urban areas. To mitigate the problems caused by flooding, unstructured data such as images and videos collected from closed circuit televisions (CCTVs) or unmanned aerial vehicles (UAVs) have been examined for flood management (FM). Many computer vision (CV) techniques have been widely adopted to analyze imagery data. Although some papers have reviewed recent CV approaches that utilize UAV images or remote sensing data, less effort has been devoted to studies that have focused on CCTV data. In addition, few studies have distinguished between the main research objectives of CV techniques (e.g., flood depth and flooded area) for a comprehensive understanding of the current status and trends of CV applications for each FM research topic. Thus, this paper provides a comprehensive review of the literature that proposes CV techniques for aspects of FM using ground camera (e.g., CCTV) data. Research topics are classified into four categories: flood depth, flood detection, flooded area, and surface water velocity. These application areas are subdivided into three types: urban, river and stream, and experimental. The adopted CV techniques are summarized for each research topic and application area. The primary goal of this review is to provide guidance for researchers who plan to design a CV model for specific purposes such as flood-depth estimation. Researchers should be able to draw on this review to construct an appropriate CV model for any FM purpose.

• 한국통신학회논문지
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• 제29권3C호
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• pp.374-386
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• 2004

유방암은 최근에 빠르게 증가하고 있는 여성 암중의 하나이며 그 발명원인이 불명확하여 조기 검출만이 생존율을 높일 수 있는 유일한 방법이다. 본 논문에서는 효율적으로 미소석회질의 의심 영역을 검출할 수 있는 방법에 대하여 설명한다. 본 논문에서는 디지털 마모램 영상에 대한 통계적 분석으로부터 일반적인 미소석회질의 특성을 분석한 후 분석된 자료를 이용하여 다단 신경망을 구성한 후 의심영역으로 간주되는 ROI를 검출한다. ROI 검출을 위하여 4단계로 구성되는 알고리즘을 제안하며 전처리 과정, 다단계 thresholding, 선형필터를 이용한 1차 미소석회질 선별작업, 다단계 신경망을 이용한 2차 미소석회질 검출이 포함된다. 선형필터를 이용한 1차 선별작업에서는 모든 미소석회질을 검출할 수 있었고 유방조직 제거를 통한 신경망에서의 작업처리 감소율이 86％로 나타났다. 2단 신경망을 이용한 2차 미소석회질 검출단계에서 첫 번째 신경망에서는 미소석회질의 형태적 특성을 기반으로 11개의 특징 값들을 정의하였으며 모든 데이터에 대한 실험 결과 평균 96.66％의 인식률을 보였다. 그리고 두 번째 신경망에서는 첫 번째 인식 결과 값과 미소석회질의 군집특성을 이용하기 위해 첫 번째 인식결과를 토대로 조사된 군집분포 여부를 특징 값으로 사용하였으며 그 결과 1차 신경망보다 높은 평균 98.26％의 인식률을 보였다.

• 인터넷정보학회논문지
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• 제4권6호
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• pp.57-67
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• 2003

최근 멀티미디어 처리 기술과 광학 기술의 발달과 더불어 얼굴 영상 정보를 이용한 응용 시스템에 대한 관심이 증대되고 있다. 기존의 얼굴 정보와 관련한 연구들은 대부분 정면 영상을 해석하여 사람을 식별하거나 영상의 표정을 분석하는데 초점을 두어왔으며 임의의 얼굴 영상의 방향성에 대한 연구는 부족한 실정이다. 특히, 한대의 카메라로 연속 촬영된 이미지들을 이용하는 기존의 방향성 검출 기법에서는 초기 영상이 정면 영상이어야 하는 제약점을 가진다. 본 논문에서는 얼굴의 특징 정보를 이용하여 임의의 얼굴 영상의 방항성을 검출하는 기법을 제안한다. 제안된 기법에서는 두 눈과 입술의 특징점을 기반으로 얼굴 사다리꼴을 정의하고, 얼굴 사다리꼴의 좌$.$우 면적을 비교한 통계 데이터를 이용하여 얼굴 영상의 좌.우 방향성을 계산하는 방향성 함수를 정의한다. 제안된 얼굴 영상의 검출 기법은 얼굴 영상의 방향성에 따라 얼굴 영상의 좌$.$우 여백을 안정적으로 설정하는 영상의 자동 배치 응용에 효과적으로 활용될 수 있다.

• 대한산업공학회지
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• 제29권2호
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• pp.165-171
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• 2003

Visual search in an unstructured search field is a fruitful research area for computational modeling. Search models that describe relationship between search time and probability of target detection have been used for prediction of human search performance and provision of ideal goals for search training. Until recently, however, most of models were focused on detecting a single target in a search field, although, in practice, a search field includes multiple targets and search models for multiple targets may differ from search models for a single target. This study proposed a random search model for multiple targets, generalizing a random search model for a single target which is the most typical search model. To test this model, human search data were collected and compared with the model. This model well predicted human performance in visual search for multiple targets. This paper also proposed how to determine optimal stopping time in multiple-target search.

• 대기
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• 제25권2호
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• pp.367-374
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• 2015

Korean Peninsula has high potential for occurrence of aviation turbulence. A Korean aviation Turbulence Guidance (KTG) system focused on the Korean Peninsula, named Korean-Peninsula KTG (KP-KTG) system, is developed using the high resolution (horizontal grid spacing of 1.5 km) Local Data Assimilation and Prediction System (LDAPS) of the Korea Meteorological Administration (KMA). The KP-KTG system is constructed first by selection of 15 best diagnostics of aviation turbulence using the method of probability of detection (POD) with pilot reports (PIREPs) and the LDAPS analysis data. The 15 best diagnostics are combined into an ensemble KTG predictor, named KP-KTG, with their weighting scores computed by the values of area under curve (AUC) of each diagnostics. The performance of the KP-KTG, represented by AUC, is larger than 0.84 in the recent two years (June 2012~May 2014), which is very good considering relatively small number of PIREPs. The KP-KTG can provide localized turbulence forecasting in Korean Peninsula, and its skill score is as good as that of the operational-KTG conducting in East Asia.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.369-372
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• 2008

Recently, landslides have frequently occurred on natural slopes during periods of intense rainfall. With a rapidly increasing population on or near steep terrain in Korea, landslides have become one of the most significant natural hazards. Thus, it is necessary to protect people from landslides and to minimize the damage of houses, roads and other facilities. To accomplish this goal, many landslide prediction methods have been developed in the world. In this study, a simple landslide prediction system that enables people to escape the endangered area is introduced. The system is focused to debris flows which happen frequently during periods of intense rainfall. The system is based on the wireless sensor network (WSN) that is composed of sensor nodes, gateway, and server system. Sensor nodes comprising a sensing part and a communication part are developed to detect ground movement. Sensing part is designed to measure inclination angle and acceleration accurately, and communication part is deployed with Bluetooth (IEEE 802.15.1) module to transmit the data to the gateway. To verify the feasibility of this landslide prediction system, a series of experimental studies was performed at a small-scale earth slope equipped with an artificial rainfall dropping device. It is found that sensing nodes installed at slope can detect the ground motion when the slope starts to move. It is expected that the landslide prediction system by wireless senor network can provide early warnings when landslides such as debris flow occurs.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.328-330
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• 2003

The land cover of burned area has changed dramatically since Daxinganling forest fire in Northeastern China during May 6 ? June 4, 1987. This research focused on determining the burn severity and assessment of forest recovery. Burned severity was classified into three levels from June 1987 Landsat TM data acquired just after the fire. A regression model was established between the forest canopy closure from 1999 forest stand map and the NDVI values from June 2000 Landsat ETM+ data. The map of canopy closure was got according to the regression model. And vegetation cover was classified into four types according to forest closure density. The change matrix was built using the classified map of burn severity and vegetation recovery. Then the change conversions of every forest type were analyzed. Results from this research indicate: forest recovery status is well in most of burned scars; and vegetation change detection can be accomplished using postclassification comparison method.

• 대한원격탐사학회지
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• 제11권2호
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• pp.59-73
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• 1995

The study is focused on the analysis of geomorphological environment changes of alluvial bar in lower Kum river using satellite-based multitemporal/multisensor data. Landsat datas for environment changes analysis consists of Landset MSS(2 scenes) and Landset TM(7 scenes) acquired from 1979 to 1994. This study is to develop the analysis techniques for the environment change detection of using ratio, classification, false color composite etc, of Landsat data especially useful to the geomorphological study of tidal flats and river channels. The results of this study can be summarized as follows : 1. The lower Kum River alluvial bar have had rapid geomorphological changes after the construction of the temporary dam to block the river flowing in 1983. The most alluvial bar located in the river has both bankway growth, especially the allurival bar in the Lower Kum River had grown between 1983 to 1990. 2. After construction of the estuarine barrage, no remarkable geomorphological changes have been found in Kum River area but the growth and formation of new underwater bar has continued. The enormous materials was needed for the growth and formations of new underwater barrier oslands and bar would be supplied from the sea bottom and river sediment to diminish of stream velocity after construction of the estuarine barrage.

• Journal of Plant Biotechnology
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• 제46권2호
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• pp.61-70
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• 2019

There is vast genetic diversity of Myanmar Mangoes. This study mainly focused on indigenous thirteen different mango landraces cultivated in central area of Myanmar, Kyauk-se District and their fruit characteristics by 18 descriptors together with genetic relationship among them by 12 SSR markers. Based on the morpho-physical characters, a wide variation among accessions was found. Genetic characterization of thirteen mango genotypes resulted in the detection of 302 scorable polymorphic bands with an average of 4.33 alleles per locus and an average polymorphism information content (PIC) of 0.7. All the genotypes were grouped into two major clusters by UPGMA cluster analysis and a genetic similarity was observed in a range of 61 ~ 85%. This study may somehow contribute insights into the identification of regional mango diversity in Myanmar and would be useful for future mango breeding program.

• 전자통신동향분석
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• 제38권6호
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• pp.62-74
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• 2023

In response to diverse external stimuli, sensory receptors generate spiking nerve signals. These generated signals are transmitted to the brain along the neural pathway to advance to the stage of recognition or perception, and then they reach the area of discrimination or judgment for remembering, assessing, and processing incoming information. We review research trends in neuromorphic sensory perception technology inspired by biological sensory perception functions. Among the various senses, we consider sensory nerve decoding technology based on sensory nerve pathways focusing on touch and smell, neuromorphic synapse elements that mimic biological neurons and synapses, and neuromorphic processors. Neuromorphic sensory devices, neuromorphic synapses, and artificial sensory memory devices that integrate storage components are being actively studied. However, various problems remain to be solved, such as learning methods to implement cognitive functions beyond simple detection. Considering applications such as virtual reality, medical welfare, neuroscience, and cranial nerve interfaces, neuromorphic sensory recognition technology is expected to be actively developed based on new technologies, including combinatorial neurocognitive cell technology.