• Title/Summary/Keyword: Spectral graph

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A New Shape-Based Object Category Recognition Technique using Affine Category Shape Model (Affine Category Shape Model을 이용한 형태 기반 범주 물체 인식 기법)

  • Kim, Dong-Hwan;Choi, Yu-Kyung;Park, Sung-Kee
    • The Journal of Korea Robotics Society
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    • v.4 no.3
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    • pp.185-191
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    • 2009
  • This paper presents a new shape-based algorithm using affine category shape model for object category recognition and model learning. Affine category shape model is a graph of interconnected nodes whose geometric interactions are modeled using pairwise potentials. In its learning phase, it can efficiently handle large pose variations of objects in training images by estimating 2-D homography transformation between the model and the training images. Since the pairwise potentials are defined on only relative geometric relationship betweenfeatures, the proposed matching algorithm is translation and in-plane rotation invariant and robust to affine transformation. We apply spectral matching algorithm to find feature correspondences, which are then used as initial correspondences for RANSAC algorithm. The 2-D homography transformation and the inlier correspondences which are consistent with this estimate can be efficiently estimated through RANSAC, and new correspondences also can be detected by using the estimated 2-D homography transformation. Experimental results on object category database show that the proposed algorithm is robust to pose variation of objects and provides good recognition performance.

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Distance Measurement Method using Deviation Due to Infrared Spectral Reflectance (적외선 분광 반사율에 의한 편차를 활용한 거리 측정 방법)

  • Mo, Gwi-hwan;Yang, Jae-hyeok;Kim, Su-min
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.10a
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    • pp.262-265
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    • 2021
  • The purpose of this development is to prevent accidents in the telephone poles caused by bird nests in advance. It is a sensor node installed on a telephone pole to recognize a bird's nest. This is to remove the bird before it builds a nest and lays eggs. It is in the system that recognizes the bird nest by the change of the distance when the sensor is first installed and the distance value measured thereafter. In this paper, we have designed and tested infrared rays with concrete, iron plate, wood, and plastic bag are targeted. This is an object that can be detected within a telephone pole was tested. The value of the spectrum detected by the spectral reflectance was obtained through a photodiode. Through the standard deviation graph of these values, it became possible to predict the target of the object and measure the distance. As a result of this experiment, target information (concrete, iron plate, wood, plastic bag) about dangerous substances in the telephone pole was acquired through the infrared sensor. Through this, it is expected that it will contribute to the establishment of a safe power grid and a coexistence environment with nature through power grid monitoring.

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AUTOMATIC IMAGE SEGMENTATION OF HIGH RESOLUTION REMOTE SENSING DATA BY COMBINING REGION AND EDGE INFORMATION

  • Byun, Young-Gi;Kim, Yong-II
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.72-75
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    • 2008
  • Image segmentation techniques becoming increasingly important in the field of remote sensing image analysis in areas such as object oriented image classification. This paper presents a new method for image segmentation in High Resolution Remote Sensing Image based on Seeded Region Growing (SRG) and Edge Information. Firstly, multi-spectral edge detection was done using an entropy operator in pan-sharpened QuickBird imagery. Then, the initial seeds were automatically selected from the obtained edge map. After automatic selection of significant seeds, an initial segmentation was achieved by applying SRG. Finally the region merging process, using region adjacency graph (RAG), was carried out to get the final segmentation result. Experimental results demonstrated that the proposed method has good potential for application in the segmentation of high resolution satellite images.

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Joint Mode Selection and Resource Allocation for Mobile Relay-Aided Device-to-Device Communication

  • Tang, Rui;Zhao, Jihong;Qu, Hua;Zhu, Zhengcang;Zhang, Yanpeng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.3
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    • pp.950-975
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    • 2016
  • Device-to-Device (D2D) communication underlaying cellular networks is a promising add-on component for future radio communication systems. It provides more access opportunities for local device pairs and enhances system throughput (ST), especially when mobile relays (MR) are further enabled to facilitate D2D links when the channel condition of their desired links is unfavorable. However, mutual interference is inevitable due to spectral reuse, and moreover, selecting a suitable transmission mode to benefit the correlated resource allocation (RA) is another difficult problem. We aim to optimize ST of the hybrid system via joint consideration of mode selection (MS) and RA, which includes admission control (AC), power control (PC), channel assignment (CA) and relay selection (RS). However, the original problem is generally NP-hard; therefore, we decompose it into two parts where a hierarchical structure exists: (i) PC is mode-dependent, but its optimality can be perfectly addressed for any given mode with additional AC design to achieve individual quality-of-service requirements. (ii) Based on that optimality, the joint design of MS, CA and RS can be viewed from the graph perspective and transferred into the maximum weighted independent set problem, which is then approximated by our greedy algorithm in polynomial-time. Thanks to the numerical results, we elucidate the efficacy of our mechanism and observe a resulting gain in MR-aided D2D communication.

Synchronization Algorithm and Demodulation using the Phase Transition Detection in the DSP based MPSK Receiver (DSP 기반 MPSK 수신기에서 위상천이 검출을 이용한 동기 알고리즘과 복조)

  • Lee Jun-Seo;Maing Jun-Ho;Ryu Heung-Gyoon;Park Cheol-Sun;Jang Won
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.15 no.10 s.89
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    • pp.952-960
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    • 2004
  • PSK(Phase Shift Keying) is useful because of the power and spectral efficient modulation. In this paper, no additional hardware will be needed to support various transmit mode in the suggested DSP scheme. We design and implement the synchronization algorithm for M-ary PSK(M=2, 4) demodulator based on DSP scheme, instead of complex analog PSK demodulator. TMS320C6203 is used as DSP. We check the all kinds of waveforms via the graph view window after software programming the emulation on the DSP tool. The result of implementation proves that demodulator using the suggested algorithm has equal performance with demodulator using analog circuits.

Responding to the Spectral Voice of the Outcast: Reading of William Wordsworth's "The Thorn"

  • Kang, Heewon
    • Cross-Cultural Studies
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    • v.36
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    • pp.37-59
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    • 2014
  • William Wordsworth's "The Thorn" revolves around the following questions: Who is Martha? Why does she go to the mountain top and repeat her doleful cry? To these questions, it gives us two different kinds of answers; one derives from the villagers, and the other from the narrator. This essay attempts to examine how the answers exemplify two different critical approaches to the problem of community, using Jacques Lacan's account of sexual difference in his seminar on Encore as a guiding thread of analysis. The important thing to retain here is that sexual difference in Lacan's seminar on Encore does not so much indicate biological determinations as two distinct forms of relating to the other which are intimately bound up with the question of how a community is constructed and maintained. The first form, called "masculine," suggests that it is a radical exception to a community that makes possible the community as a field of totality or sameness; the second form, called "feminine," shows that each of the subjects cannot be regarded as a member of a closed community which is guaranteed by the exceptionality, but as an exception that is radically singular. This in turn leads us to consider the possibility that the masculine form has to do with the villagers' effort to distinguish themselves from Martha and the feminine form with the way in which the narrator confronts and represents her. In the course of his formulation of sexuation graph, Lacan stresses that the masculine side must be supplemented by the feminine side, which allows us to elaborate on why, concerning Martha, the narrator does not just keep the completely different position from the villagers'. This is to say that the villagers' representation of Martha as an exception to the community should be supplemented by the narrator's attempt to tell Martha's story as the villagers do and at the same time to capture something of her enigmatic unrepresentability. Bearing in mind Charles Shepherdson's elaboration of traumatic memory, this essay also tries to clarify how the narrator preserves and even transmits something of Martha's truth that is embodied in her uncontrollable and unassimilable cry.

An Efficient Datapath Placement Algorithm to Minimize Track Density Using Spectral Method (스팩트럴 방법을 이용해 트랙 밀도를 최소화 할 수 있는 효과적인 데이터패스 배치 알고리즘)

  • Seong, Gwang-Su
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.37 no.2
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    • pp.55-64
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    • 2000
  • In this paper, we propose an efficient datapath placement algorithm to minimize track density. Here, we consider each datapath element as a cluster, and merge the most strongly connected two clusters to a new cluster until only one cluster remains. As nodes in the two clusters to be merged are already linearly ordered respectively, we can merge two clusters with connecting them. The proposed algorithm produces circular linear ordering by connecting starting point and end point of the final cluster, and n different linear ordering by cutting between two contiguous elements of the circular linear ordering. Among the n different linear ordering, the linear ordering to minimize track density is final solution. In this paper, we show and utilize that if two clusters are strongly connected in a graph, the inner product of the corresponding vectors mapped in d-dimensional space using spectral method is maximum. Compared with previous datapath placement algorithm GA/S $A^{[2]}$, the proposed algorithm gives similar results with much less computation time.

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Computational electroencephalography analysis for characterizing brain networks

  • Sunwoo, Jun-Sang;Cha, Kwang Su;Jung, Ki-Young
    • Annals of Clinical Neurophysiology
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    • v.22 no.2
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    • pp.82-91
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    • 2020
  • Electroencephalography (EEG) produces time-series data of neural oscillations in the brain, and is one of the most commonly used methods for investigating both normal brain functions and brain disorders. Quantitative EEG analysis enables identification of frequencies and brain activity that are activated or impaired. With studies on the structural and functional networks of the brain, the concept of the brain as a complex network has been fundamental to understand normal brain functions and the pathophysiology of various neurological disorders. Functional connectivity is a measure of neural synchrony in the brain network that refers to the statistical interdependency between neural oscillations over time. In this review, we first discuss the basic methods of EEG analysis, including preprocessing, spectral analysis, and functional-connectivity and graph-theory measures. We then review previous EEG studies of brain network characterization in several neurological disorders, including epilepsy, Alzheimer's disease, dementia with Lewy bodies, and idiopathic rapid eye movement sleep behavior disorder. Identifying the EEG-based network characteristics might improve the understanding of disease processes and aid the development of novel therapeutic approaches for various neurological disorders.

Study on the Effect of Emissivity for Estimation of the Surface Temperature from Drone-based Thermal Images (드론 열화상 화소값의 타겟 온도변환을 위한 방사율 영향 분석)

  • Jo, Hyeon Jeong;Lee, Jae Wang;Jung, Na Young;Oh, Jae Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.40 no.1
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    • pp.41-49
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    • 2022
  • Recently interests on the application of thermal cameras have increased with the advance of image analysis technology. Aside from a simple image acquisition, applications such as digital twin and thermal image management systems have gained popularity. To this end, we studied the effect of emissivity on the DN (Digital Number) value in the process of derivation of a relational expression for converting DN to an actual surface temperature. The DN value is a number representing the spectral band value of the thermal image, and is an important element constituting the thermal image data. However, the DN value is not a temperature value indicating the actual surface temperature, but a brightness value indicating high and low heat as brightness, and has a non-linear relationship with the actual surface temperature. The reliable relationship between DN and the actual surface temperature is critical for a thermal image processing. We tested the relationship between the actual surface temperature and the DN value of the thermal image, and then the radiation adjustment was performed to better estimate actual surface temperatures. As a result, the relation graph between the actual surface temperature and the DN value similarly show linear pattern with the relation graph between the radiation-controlled non-contact thermometer and the DN value. And the non-contact temperature after adjusting the emissivity was closer to the actual surface temperature than before adjusting the emissivity.

A Study on the Characteristics of Summer Water Temperature Fluctuations by Spectral Analysis in Coast of Korea in 2016 (스펙트럼 분석을 통한 2016년 하계 한국연안의 수온변동 특성에 관한 연구)

  • Seo, Ho-San;Jeong, Yong-Hyun;Kim, Dong-Sun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.2
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    • pp.186-194
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    • 2020
  • In this study, spectral analysis was conducted to identify environmental factors af ecting short-term changes in water temperature in the East, West and South coasts of Korea. The data used in the spectrum analysis is the 2016 summer water temperature, air temperature, tide level and wind data provided by Korea Hydrographic & Oceanographic Agency. In power spectrum results, peaks of water temperature and tide level were observed at same periods in West Sea (Incheon, Pyeungteak, Gunsan and Mokpo) and South Sea (Wando, Goheung, Yeosu, Tongyeong and Masan) where mean tidal range was more than 100 cm. On the other hand, periodicity of water temperature did not appear in East Sea and Busan where the mean tidal range was small. Coherence analysis showed that water temperature was highly correlated with tide in West Sea and three stations(Wando, Goheung and Tongyeong) of South Sea. Especially, correlation between water temperature and tide level in Wando and Tongyeong presented 0.96 at semi-diurnal period. Water temperature in Yeosu seems to have influenced by tide and inflow of fresh water. In Masan, water temperature is influenced by south wind, tide and inflow of fresh water. In East Sea, influence of tide on water temperature is small due to current and small tidal range. As a result of comparing the time series graph, stations where the correlation between water temperature and tide is high show that relatively cold water was inputted at flood tide and flow out at ebb tide. short-term variation of water temperature was affected by tide, but long-term variation over a month was affected by air temperature.