• Title/Summary/Keyword: directional selectivity

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The Three Directional Separable Processing Method for Double-Density Wavelet Transformation Improvement (이중 밀도 웨이브렛 변환의 성능 향상을 위한 3방향 분리 처리 기법)

  • Shin, Jong Hong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.2
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    • pp.131-143
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    • 2012
  • This paper introduces the double-density discrete wavelet transform using 3 direction separable processing method, which is a discrete wavelet transform that combines the double-density discrete wavelet transform and quincunx sampling method, each of which has its own characteristics and advantages. The double-density discrete wavelet transform is nearly shift-invariant. But there is room for improvement because not all of the wavelets are directional. That is, although the double-density DWT utilizes more wavelets, some lack a dominant spatial orientation, which prevents them from being able to isolate those directions. The dual-tree discrete wavelet transform has a more computationally efficient approach to shift invariance. Also, the dual-tree discrete wavelet transform gives much better directional selectivity when filtering multidimensional signals. But this transformation has more cost complexity Because it needs eight digital filters. Therefor, we need to hybrid transform which has the more directional selection and the lower cost complexity. A solution to this problem is a the double-density discrete wavelet transform using 3 direction separable processing method. The proposed wavelet transformation services good performance in image and video processing fields.

Learning-possibility for neuron model in Medical Superior Temporal area

  • Sekiya, Yasuhiro;Zhu, Hanxi;Aoyama, Tomoo;Tang, Zheng
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.516-516
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    • 2000
  • We propose a neuron model that is possible to learn three-dimensional movement. The neuron model by imitating structure of a neuron, has the system resemble a neuron. We considered a neuron system based on the arguments, and wished to examine whether the system had reasonable function. Koch, Poggio and Torre believed that inhibition signal would shunt excitation signal on the dendrites. They believed that excitation signal operated input-signals and inhibition did as delayed ones. Thus, they were sure that function for directional selectivity was arisen by the shunting. Koch's concept is so important; therefore, we construct the neuron system with their concept. The neuron system makes the shunting function; thus, the model may have a function for directional selectivity. We initialized the connections and the dendrites by random data, and trained them by the back-propagation algorithm for three-dimensional movement. We made sure the defection of three-dimensional movement in the system.

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A Directional Relay Algorithm Using Positive-Sequence Superimposed Quantity for Transmission Line Protection (정상 성분 변화량을 이용한 송전선로 보호용 방향 계전 알고리즘)

  • 이명수;유석구
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.52 no.4
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    • pp.226-233
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    • 2003
  • Directional elements are fundamental to protection scheme security and selectivity, performing such critical tasks as supervising distance elements and controlling overcurrent elements. But, conventional operating principles for directional detection based on negative or zero sequence quantify do not satisfy the requirements for improved sensitivity and fast operation under any fault conditions. In this paper, new algorithm for directional elements is proposed. The proposed algorithm use the positive-sequence superimposed voltages and currents in order to be used in all fault conditions. Also, because this algorithm uses a voltage compensation method. it can be well operated under strong source conditions.

Dual-tree Wavelet Discrete Transformation Using Quincunx Sampling For Image Processing (디지털 영상 처리를 위한 Quincunx 표본화가 사용된 이중 트리 이산 웨이브렛 변환)

  • Shin, Jong Hong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.7 no.4
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    • pp.119-131
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    • 2011
  • In this paper, we explore the application of 2-D dual-tree discrete wavelet transform (DDWT), which is a directional and redundant transform, for image coding. DDWT main property is a more computationally efficient approach to shift invariance. Also, the DDWT gives much better directional selectivity when filtering multidimensional signals. The dual-tree DWT of a signal is implemented using two critically-sampled DWTs in parallel on the same data. The transform is 2-times expansive because for an N-point signal it gives 2N DWT coefficients. If the filters are designed is a specific way, then the sub-band signals of the upper DWT can be interpreted as the real part of a complex wavelet transform, and sub-band signals of the lower DWT can be interpreted as the imaginary part. The quincunx lattice is a sampling method in image processing. It treats the different directions more homogeneously than the separable two dimensional schemes. Quincunx lattice yields a non separable 2D-wavelet transform, which is also symmetric in both horizontal and vertical direction. And non-separable wavelet transformation can generate sub-images of multiple degrees rotated versions. Therefore, non-separable image processing using DDWT services good performance.

Dynamic properties of the retinal neurons by using of the intracellular recording method (세포내 기록법으로써 검출한 망막 신경원의 동적 특성)

  • 이성종;정창섭;배선호
    • Progress in Medical Physics
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    • v.9 no.2
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    • pp.95-104
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    • 1998
  • The dynamic properties of the 3rd-order neuron of the retina was investigated by using conventional intracellular recording techniques. Experiments were performed in the superfused retina-eyecup preparation of the channel catfish, Ictalurus punctatus. The cornea, iris, lens, and vitreous were removed by absorption with Kimwipe tissue under the dissection microscope thereby exposing the retina in a hemi -eyecup. The electrical signal was amplified by electrometer, viewed on oscilloscope. Regular signals from the cells were recorded on a penwriter and stored by data recorder and computer. Full-field, spot or annular light stimuli were generated on a computer monitor and focused onto the retina. Baclofen hyperpolarized the dark membrane potential, suppressed sustained component and enhanced transient component of the ON-sustained cell with a large transient component, but did not affect the surround antagonism of the cell. Baclofen selectively suppressed responses evoked by moving bar light stimuli on the ON-OFF transient cell. The results suggest that transient cells have directional selectivity in the inner retina. These dynamic properties of amacrine and ganglion cells were modulated by baclofen. Therefore, it is presumed that there is baclofen-induced directional selectivity in ON-OFF transient cells in the catfish retina.

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A New Scheme to Improve High Impedance Fault Detection Capability Using Directional Over-Current Ground Relay (방향지락과전류계전기를 이용한 고저항지락사고 검출능력의 향상방안)

  • Lee, Seung-Jae;Lim, Jong-Yun;Kim, Il-Dong;Han, Kyoung-Nam
    • Proceedings of the KIEE Conference
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    • 1997.07c
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    • pp.1000-1002
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    • 1997
  • In this paper we proposes a scheme which can improve the detecting capability of the high impedance fault of the conventional distance relaying. It utilizes the directional ground overcurrent relay called HIFR together with the distance relay in order to secure the security and selectivity.

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Improvement of Double Density Discrete Wavelet Transformation with Enhancement of Directional Selectivity (방향의 선택성 향상을 통한 이중 밀도 이산 웨이브렛 변환의 성능 개선)

  • Lim, Joong-Hee;Shin, Jong-Hong;Jee, Inn-Ho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.2
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    • pp.221-232
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    • 2012
  • The double-density discrete wavelet transform(DWT) is an improvement upon the critically sampled DWT with important additional properties. It employs one scaling function and two distinct wavelets, which are designed to be offset from one another by one half. And it is overcomplete by a factor of two. Also, this transformation is nearly shift-invariant. But there is room for improvement because not all of the wavelets are directional. That is, although the double-density DWT utilizes more wavelets, some lack a dominant spatial orientation, which prevents them from being able to isolate those directions. Proposed method is a DWT that combines the double-density DWT and quincunx sampling, each of which has its own characteristics and advantages. Especially, the quincunx sampling treats the different directions more homogeneously. As a result, since proposed method can generate sub-images of multiple degrees rotated versions, this method provides an improved performance in image processing fields.

METHOD FOR REAL-TIME EDGE EXTRACTION USING HARDWARE OF LATERAL INHIVITION TYPE OF SPATIAL FILTER

  • Serikawa, Seiichi;Morita, Kazuhiro;Shimomura, Teruo
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.236-239
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    • 1995
  • It is useful to simulate the human visual function for the purpose of image-processing. In this study, the hardware of the spatial filter with the sensitivity of lateral inhibition is realized by the combination of optical parts with electronic circuits. The diffused film with the characteristics of Gaussian type is prepared as a spatial filter. An object's image is convoluted with the spatial filter. From the difference of the convoluted images, the zero-cross position is detected at video rate. The edge of object is extracted in real-time by the use of this equipment. The resolution of edge changes with the value of the standard deviation of diffused film. In addition, it is possible to extract a directional edge selectively when the spatial filter with directional selectivity is used instead of Gaussian type of spatial filter.

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Quincunx Sampling Method For Improvement of Double-Density Wavelet Transformation (이중 밀도 웨이브렛 변환의 성능 향상을 위한 Quincunx 표본화 기법)

  • Lim, Joong Hee;Shin, Jong Hong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.1
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    • pp.171-181
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    • 2012
  • This paper introduces the double-density discrete wavelet transform(DWT) using quincunx sampling, which is a DWT that combines the double-density DWT and quincunx sampling method, each of which has its own characteristics and advantages. The double-density DWT is an improvement upon the critically sampled DWT with important additional properties: Firstly, It employs one scaling function and two distinct wavelets, which are designed to be offset from one another by one half. Secondly, the double-density DWT is overcomplete by a factor of two, and Finally, it is nearly shift-invariant. In two dimensions, this transform outperforms the standard DWT in terms of denoising; however, there is room for improvement because not all of the wavelets are directional. That is, although the double-density DWT utilizes more wavelets, some lack a dominant spatial orientation, which prevents them from being able to isolate those directions. A solution to this problem is a quincunx sampling method. The quincunx lattice is a sampling method in image processing. It treats the different directions more homogeneously than the separable two dimensional schemes. Proposed wavelet transformation can generate sub-images of multiple degrees rotated versions. Therefore, This method services good performance in image processing fields.

A neuron model that a moving object can be recognized in the planer region

  • Sekiya, Yasuhiro;Aoyama, Tomoo;Tamura, Hiroki;Tang, Zheng
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.149.6-149
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    • 2001
  • We propose a neuron model that has the interactions between excitation and inhibition. By adopting the knowledge of the physiology, the neuron model by imitating structure of a neuron, has the system resemble a neuron. We considered a neuron system based on the arguments, and wished to examine whether the system had reasonable function Koch, Poggio and Torre believed that inhibition signal would shunt excitation signal on the dendrites. They believed that excitation signal operated input signals and inhibition did as delayed ones. Thus, they were sure that function for directional selectivity was arisen by the shunting. We construct the neuron system with Koch's concept. Our neuron model has 3-layer structure and ...

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