• Title/Summary/Keyword: Cascading

검색결과 170건 처리시간 0.03초

Family of Cascade-correlation Learning Algorithm (캐스케이드-상관 학습 알고리즘의 패밀리)

  • Choi Myeong-Bok;Lee Sang-Un
    • Journal of the Korean Institute of Intelligent Systems
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    • 제15권1호
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    • pp.87-91
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    • 2005
  • The cascade-correlation (CC) learning algorithm of Fahlman and Lebiere is one of the most influential constructive algorithm in a neural network. Cascading the hidden neurons results in a network that can represent very strong nonlinearities. Although this power is in principle useful, it can be a disadvantage if such strong nonlinearity is not required to solve the problem. 3 models are presented and compared empirically. All of them are based on valiants of the cascade architecture and output neurons weights training of the CC algorithm. Empirical results indicate the followings: (1) In the pattern classification, the model that train only new hidden neuron to output layer connection weights shows the best predictive ability; (2) In the function approximation, the model that removed input-output connection and used sigmoid-linear activation function is better predictability than CasCor algorithm.

Tracking the Source of Cascading Cyber Attack Traffic Using Network Traffic Analysis (네트워크 트래픽 분석을 이용한 연쇄적 사이버공격 트래픽의 발생원 추적 방법)

  • Goo, Young-Hoon;Choi, Sun-Oh;Lee, Su-Kang;Kim, Sung-Min;Kim, Myung-Sup
    • The Journal of Korean Institute of Communications and Information Sciences
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    • 제41권12호
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    • pp.1771-1779
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    • 2016
  • In these days, the world is getting connected to the internet like a sophisticated net, such an environment gives a suitable environment for cyber attackers, so-called cyber-terrorists. As a result, a number of cyber attacks has significantly increased and researches to find cyber attack traffics in the field of network monitoring has also been proceeding. But cyber attack traffics have been appearing in new forms in every attack making it harder to monitor. This paper suggests a method of tracking down cyber attack traffic sources by defining relational information flow of traffic data from highest cascaded and grouped relational flow. The result of applying this cyber attack source tracking method to real cyber attack traffic, was found to be reliable with quality results.

A Study on the Adaptive Technique for Artifact Cancelling in Electroencephalogram Analysis System (뇌파 분석 시스템에서의 Artifact 제거를 위한 적응 기법에 관한 연구)

  • 유선국;김기만;남기현
    • Journal of Biomedical Engineering Research
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    • 제18권4호
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    • pp.389-396
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    • 1997
  • Several types of electrical artifact seen on electroencephalogram( EEG) records are described. Those are the EOG and the PVC roller pump noise, and so on. An adaptive digital filtering of the electroencephalogram( EEG) is a successful way of suppressing mains interference, but it affects some of the frequency components of the signal, whore artifacts may not be acceptable in some cafes of automatic EEG processing. Thus we studied the method for cancelling these artifacts. This proposed method does not use the reference channel, and is realized by connecting the linear predictor and the fixed FIR filter for the EOG artifact, and by cascading the linear predictor and the noise canceller for the pump artifact. The simulation results illustrate the performances of the proposed method in terms of the capability of interferences suppression. In the results we obtained about 20 dB noise reduction.

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A 500MSamples/s 6-Bit CMOS Folding and Interpolating AD Converter (500MSamples/s 6-비트 CMOS 폴딩-인터폴레이팅 아날로그-디지털 변환기)

  • Lee Don-Suep;Kwack Kae-Dal
    • Journal of the Korea Institute of Information and Communication Engineering
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    • 제8권7호
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    • pp.1442-1447
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    • 2004
  • In this paper, a 6-Bit CMOS Folding and Interpolating AD Converter is presented. The converter is considered to be useful as an integrated part of a VLSI circuit handling both analog and digital signals as in the case of HDD or LAN applications. A built-in analog circuit for VLSI of a high-speed data communication requires a small chip area, low power consumption, and fast data processing. The proposed folding and interpolating AD Converter uses a very small number of comparators and interpolation resistors, which is achieved by cascading a couple of folders working in different principles. This reduced number of parts is a big advantage for a built-in AD converter design. The design is based on 0.25m double-poly 2 metal n-well CMOS process. In the simulation, with the applied 2.5V and a sampling frequency of 500MHz, the measurements are as follows: power consumption of 27mw, INL and DNL of $\pm$0.1LSB, $\pm$0.15LSB each, SNDR of 42dB with an input signal of 10MHz.

Inverted Indexes for XML Updates and Full-Text Retrievals in Relational Model (관계형 모델에서 XML 변경과 전문 검색을 지원하기 위한 역 인덱스 구축 기법)

  • Cheon, Yun-Woo;Hong, Dong-Kweon
    • The KIPS Transactions:PartD
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    • 제11D권3호
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    • pp.509-518
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    • 2004
  • Recently there has been some efforts to add XML full-text retrievals and XML updates into new standardization of XML queries. XML full-text retrievals plays an important role in XML query languages. of like tables in relational model an XML document has complex and unstructured natures. We believe that when we try to get some information from unstructured XML documents a full-text retrieval query is much more convenient approach than a regular structured query XML update is another core function that an XML query have to have. In this paper we propose an inverted index to support XML updates and XML full-text queries in relational environment. Performance comparisons exhibit that our approach maintains a comparable size of inverted indexes and it supports many full-text retrieval functions very well. It also shows very stable retrieval performance especially for large size of XML documents. Foremost our approach handles XML updates efficiently by removing cascading effects.

Open-Loop Pipeline ADC Design Techniques for High Speed & Low Power Consumption (고속 저전력 동작을 위한 개방형 파이프라인 ADC 설계 기법)

  • Kim Shinhoo;Kim Yunjeong;Youn Jaeyoun;Lim Shin-ll;Kang Sung-Mo;Kim Suki
    • The Journal of Korean Institute of Communications and Information Sciences
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    • 제30권1A호
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    • pp.104-112
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    • 2005
  • Some design techniques for high speed and low power pipelined 8-bit ADC are described. To perform high-speed operation with relatively low power consumption, open loop architecture is adopted, while closed loop architecture (with MDAC) is used in conventional pipeline ADC. A distributed track and hold amplifier and a cascading structure are also adopted to increase the sampling rate. To reduce the power consumption and the die area, the number of amplifiers in each stage are optimized and reduced with proposed zero-crossing point generation method. At 500-MHz sampling rate, simulation results show that the power consumption is 210mW including digital logic with 1.8V power supply. And the targeted ADC achieves ENOB of about 8-bit with input frequency up to 200-MHz and input range of 1.2Vpp (Differential). The ADC is designed using a $0.18{\mu}m$ 6-Metal 1-Poly CMOS process and occupies an area of $900{\mu}m{\times}500{\mu}m$

Motion Adaptive Temporal-Spatial Noise Reduction Scheme with Separated Pre- and Post-Spatial Filter (분리된 전처리 및 후처리 광간영역 필터를 가진 움직임 적응적 시공간영역 잡음 제거 기법)

  • Kim, Sung-Deuk;Lim, Kyoung-Won
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • 제46권5호
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    • pp.40-47
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    • 2009
  • A motion adaptive video noise reduction scheme is proposed by cascading a temporal filter and a spatial filter. After a noise-robust motion detection is performed with a pre-spatial filter, the strength of the motion adaptive temporal filter is controlled by the amount of temporal movement. In order to fully utilize the temporal correlation of video signal, noisy input image is processed first by the temporal filter, therefore, image details of temporally stationary region are quite well preserved while undesired noises are suppressed. In contrast to the pre-spatial filter used for the robust motion detection, the cascaded post-spatial filter removes the remained noises by considering the strength of the temporal filter and the spatial self-similarity search results obtained from the pre-spatial filter.

Analysis of the Degraded Performance and Restoration Plan of Lfieline Systems Considering Interdependency in the Post-disaster (라이프라인 시스템 상호의존성을 고려한 기능 저하 평가 및 복구계획 분석)

  • Lee, Seulbi;Park, Moonseo;Lee, Hyun-Soo;Hwang, Sungjoo
    • Korean Journal of Construction Engineering and Management
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    • 제15권4호
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    • pp.139-149
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    • 2014
  • Lifeline service disruptions can have significant impacts on local community in the aftermath natural disaster. Although effective restoration strategies with accurate damage assessment are required, the internal complexity of lifeline networks and their interdependency makes the understanding restoration process of lifeline systems a difficult issue. Additionally, the limitations of previous research relating the influence assessment of lifeline to community disaster resilience, highlight the need for understanding of lifeline networks. Therefore, this paper presents an agent-based model to discover emergent behavior and evaluate the interdependency and resiliency in lifeline networks. This research will provide basic guideline of resource allocation in order to mitigate cascading failures of the post disaster restoration processes.

Design of a Compact Narrow Band Pass Filter Using the Circular CSRR (원형 CSRR를 이용한 소형 협 대역통과 필터 설계)

  • Choi, Dong-Muk;Kim, Dang-Oh;Kim, Che-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • 제34권11A호
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    • pp.918-923
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    • 2009
  • In this paper, a design method of the compact narrow band filter on the microstrip board is proposed using complementary split-ring resonators(CSRRs). The design technique of this filter is based on cascading filter stages consisting of the combination of circular CSRRs, capacitive gaps between patches, and inductive grounded stubs with the meander configuration. By these means, it was possible to get the nearly symmetric frequency responses, adjustable bandwidths, compact sizes. And also excellent characteristic of the out-of-band rejection is achieved in contrast to the conventional filter design technique. The measured insertion shows good results about -4.0dB at the center frequency($f_0=1GHz$) and passband return loss is less than -9.4dB. The 3dB fractional bandwidth(FBW) is approximately 4%. The results of the frequency response measured on the fabricated band pass filter substrate show satisfactory agreement with the simulated frequency responses by the HFSS in the region of interest.

Fast Ambiguity Resolution using Galileo Multiple Frequency Carrier Phase Measurement

  • Ji, Shengyue;Chen, Wu;Zhao, Chunmei;Ding, Xiaoli;Chen, Yongqi
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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    • pp.179-184
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    • 2006
  • Rapid and high-precision positioning with a Global Navigation Satellite System (GNSS) is feasible only when very precise carrier-phase observations can be used. There are two kinds of mathematical models for ambiguity resolution. The first one is based on both pseudorange and carrier phase measurements, and the observation equations are of full rank. The second one is only based on carrier phase measurement, which is a rank-defect model. Though the former is more commonly used, the latter has its own advantage, that is, ambiguity resolution will be freed from the effects of pseudorange multipath. Galileo will be operational. One of the important differences between Galileo and current GPS is that Galileo will provide signals in four frequency bands. With more carrier-phase data available, frequency combinations with long equivalent wavelength can be formed, so Galileo will provide more opportunities for fast and reliable ambiguity resolution than current GPS. This paper tries to investigate phase only fast ambiguity resolution performance with four Galileo frequencies for short baseline. Cascading Ambiguity Resolution (CAR) method with selected optimal frequency combinations and LAMBDA method are used and compared. To validate the resolution, two tests are used and compared. The first one is a ratio test. The second one is lower bound success-rate test. The simulation test results show that, with LAMBDA method, whether with ratio test or lower bound success rate validation criteria, ambiguity can be fixed in several seconds, 8 seconds at most even when 1 sigma of carrier phase noise is 12 mm. While with CAR method, at least about half minute is required even when 1 sigma of carrier phase noise is 3 mm. It shows that LAMBDA method performs obviously better than CAR method.

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