• Title/Summary/Keyword: 역 필터

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Shadow Regulation of Online Copyright Protection and Its Implications (온라인상 저작권 보호에 관한 그림자규제와 시사점)

  • Kim, Ho
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.4
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    • pp.289-294
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    • 2019
  • Although regulation generally shall be based on the law, many regulations are not based on legislation. Shadow regulation that is not mandatory but functions as regulation may be developed and enforced by non-govermental body. This article examines shadow regulations of copyright protection online of the US, the EU and the UK and draws their implications for Korea. In case of self-regulation, the following factors shall be considered: to acquire the technology to filter copyright infringement and to solve the problems arising from the application of it, to prevent the infringement of freedom of expression, to ensure the appropriateness of the sanctions imposed on the alleged copyright infringement, to ensure the participation or monitoring of internet subscribers in the negotiation between the internet industry and copyright holders, and to clarify the government's role and responsibility.

Wideband Multi-bit Continuous-Time $\Sigma\Delta$ Modulator with Adaptive Quantization Level (적응성 양자화 레벨을 가지는 광대역 다중-비트 연속시간 $\Sigma\Delta$ 모듈레이터)

  • Lee, Hee-Bum;Shin, Woo-Yeol;Lee, Hyun-Joong;Kim, Suh-Wan
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.11
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    • pp.1-8
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    • 2007
  • A wideband continuous-time sigma delta modulator for wireless application is implemented in 130nm CMOS. The SNR for small input signal is improved using a proposed adaptive quantizer which can effectively scale the quantization level. The modulator comprises a second-order loop filter for low power consumption, 4-bit quantizer and DAC for low jitter sensitivity and high linearity. Designed circuit achieves peak SNR of 51.36B with 10MHz signal Bandwidth and 320MHz sampling frequency dissipating 30mW.

Estimation of Surface Spectral Reflectance using A Population with Similar Colors (유사색 모집단을 이용한 물체의 분광 반사율 추정)

  • 이철희;서봉우;안석출
    • Journal of Korea Multimedia Society
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    • v.4 no.1
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    • pp.37-45
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    • 2001
  • The studies to estimate the surface spectral reflectance of an object have received widespread attention using the multi-spectral camera system. However, the multi-spectral camera system requires the additional color filter according to increment of the channel and system complexity is increased by multiple capture. Thus, this paper proposes an algorithm to reduce the estimation error of surface spectral reflectance with the conventional 3-band RGB camera. In the proposed method, adaptive principal components for each pixel are calculated by renewing the population of surface reflectances and the adaptive principal components can reduce estimation error of surface spectral reflectance of current pixel. To evaluate performance of the proposed estimation method, 3-band principal component analysis, 5-band wiener estimation method, and the proposed method are compared in the estimation experiment with the Macbeth Color Checker. As a result, the proposed method showed a lower mean square error between the estimated and the measured spectra compared to the conventional 3-band principal component analysis method and represented a similar or advanced estimation performance compared to the 5-band wiener method.

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A Study on Implementation and Performance Evaluation of Wideband Receiver for the INMARSAT-B Satellite Communications System (INMARSAT-B형 위성통신용 광대역 수신단 구현 및 성능평가에 관한 연구)

  • 전중성;임종근;김동일;김기문
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.1
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    • pp.166-172
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    • 2001
  • A RF wideband receiver for INMARSAT-B satellite communications system was composed of low noise amplifier and high gain amplifier, The low noise amplifier used to the resistive decoupling circuit for input impedance matching and self-bias circuits for low noise. The high gain amplifier consists of matched amplifier type to improve receiver gain. The active bias circuit can be used to provide temperature stability without requiring the large voltage drop or relatively high-dissipated power needed with a bias stabilization resistor. The bandpass filter was used to reduce a spurious level. As a result, the characteristics of the receiver implemented here show more than 60 dB in gain and less than 1.8:1 in input and output voltage standing wave ratio(VSWR), especially the carrier to noise ratio which is input signal level -126.7 dB m at 1537.5 MHz is a 45.23 dB /Hz at a 1.02 kHz.

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Direction-of-Arrival Estimation in Broadband Signal Processing : Rotation of Signal Subspace Approach (광대역 신호 처리에서의 도래각 추정 : Rotation of Signal Subspaces 방법)

  • Kim, Young-Soo
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.7
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    • pp.166-175
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    • 1989
  • In this paper, we present a method which is based on the concept of the rotation of subspaces. This method is highly related to the angle (or distance) between subspaces arising in many applications. An effective procedures is first derived for finding the optimal transformation matrix which rotates one subspace into another as closely as possible in the least squares sense , and then this algorithm is applied to the solution to general direction-of-arrival estimation problem of multiple broadband plane waves which may be a mixture of incoherent, partially coherent or coherent. In this typical application, the rotation of signal subspaces (ROSS) algorithm is effectively developed to achieve the high performance in the active systems for the case in which the noise field remains invariant with the measurement of the array spectral density matrix (or data matrix). It is not uncommon to observe this situation in sonar systems. The advantage of this techniques is not to require the preliminary processing and spatial prefiltering which is used in Wang-Kaveh's CSS focusing method. Furthermore, the array's geometry is not restricted. Simulation results are presented to illustrate the high performance achieved with this new approach relative to that obtained with Wang-Kaveh's CSS focusing method for incoherent sources and forward-backward spatial smoothed MUSIC for coherent sources including the signal eigenvector method (SEM).

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Digital image watermarking techniques using multiresolution wavelet transform in Sequency domain (다해상도 웨이브렛 변환을 사용한 주파수 영역에서의 디지털 영상 워터마킹 기법)

  • 신종홍;연현숙;지인호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.12A
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    • pp.2074-2084
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    • 2001
  • la this paper, a new digital watermarking algorithm using wavelet transform in frequency domain is suggested. The wavelet coefficients of low frequency subband are utilized to embed the watermark, After the original image is transformed using discrete wavelet transform, their coefficients are transformed into efficient1y in Sequency domain. DCT and FFT transforms are utilized in this processing. Watermark image of general image format is transformed using DCT and the hiding watermark into wavelet coefficients is equally distributed in frequency domain. Next, these wavelet coefficients are performed with inverse transform. The detection process of watermark is performed with reverse direction to insertion process. In this paper, we developed core watermark technologies which are a data hiding technology to hide unique logo mark which symbolizes the copyright and a robust protection technology to protect logo data from external attack like as compression, filtering, resampling, cropping. The experimental results show that two suggested watermarking technologies are invisible and robust.

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Design of High Frequency Boosting Circuits Compensating for Hearing Loss (청력 보정을 위한 고주파 증폭 회로 설계)

  • Lee, Kwang;Jung, Young-Jin
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.3
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    • pp.138-144
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    • 2017
  • In this paper, we propose a high frequency boosting circuits compensating for age-related hearing loss. The frequency response of this hearing loss is quite similar to that of a low-pass filter of which the critical frequency get lower with age. Therefore the voltage gain of this compensation circuits increase proportionally to the frequency of signals when the frequency is higher than the critical frequency and the voltage is constant irrespective of the frequency of signals when the frequency is lower than the critical frequency. The proposed circuits consist of a differential circuit and a unity gain amplifier. Because the critical frequency of the proposed circuits is controlled simply in the shape of a volume control lever, the aged people can adjust the high frequency boosting level easily according to one's hearing loss level. The critical frequency is continuously controllable in the whole audible frequency band and the gain of this high frequency boosting circuits is above 80dB at 10kHz.

Design of VHF-Band Wideband 4-Way 90° Power Divider (VHF 대역용 광대역 4분기 90° 전력분배기 설계)

  • Lee, Kyu-Song;Oh, Seung-Hyeub
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.6
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    • pp.516-525
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    • 2009
  • This paper described the design and fabrication of broadband 4-way $90^{\circ}$ power divider which has a $90^{\circ}$ phase difference between output ports in 20${\sim}$100 MHz VHF-band. A 4-way $90^{\circ}$ power divider was designed using 4-way in-phase power divider which consisted of three 2-way in-phase power dividers and two second-order all pass filters which gives $90^{\circ}$ phase difference between output ports. The measured insertion loss was less then 6.6 dB, return loss and isolation were better than 19 dB, and phase error between $90^{\circ}$ phase difference outputs was less than ${\pm}$1$^{\circ}$.

A Curve Lane Detection Method using Lane Variation Vector and Cardinal Spline (차선 변화벡터와 카디널 스플라인을 이용한 곡선 차선 검출방법)

  • Heo, Hwan;Han, Gi-Tae
    • KIPS Transactions on Software and Data Engineering
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    • v.3 no.7
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    • pp.277-284
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    • 2014
  • The detection method of curves for the lanes which is powerful for the variation by utilizing the lane variation vector and cardinal spline on the inverse perspective transformation screen images which do not required the camera parameters are suggested in this paper. This method detects the lane area by setting the expected lane area in the s frame and next s+1 frame where the inverse perspective transformation and entire process of the lane filter are adapted, and expects the points of lane location in the next frames with the lane variation vector calculation from the detected lane areas. The scan area is set from the nextly expected lane position and new lane positions are detected within these areas, and the lane variation vectors are renewed with the detected lane position and the lanes are detected with application of cardinal spline for the control points inside the lane areas. The suggested method is a powerful method for curved lane detection, but it was adopted to the linear lanes too. It showed an excellent lane detection speed of about 20ms in processing a frame.

A Study on Fabrication and Performance Evaluation of Wideband Receiver using Bias Stabilized Resistor for the Satellite Mobile Communications System (바이어스 안정화 저항을 이용한 이동위성 통신용 광대역 수신단 구현 및 성능 평가에 관한 연구)

  • 전중성;김동일;배정철
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.3 no.3
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    • pp.569-577
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    • 1999
  • A wideband RF receiver for satellite mobile communications system was fabricated and evaluated of performance in low noise amplifier and high gain amplifier. The low noise amplifier used to the resistive decoupling and self-bias circuits. The low noise amplifier is fabricated with both the RF circuits and the self-bias circuits. Using a INA-03184, the high gain amplifier consists of matched amplifier type. The active bias circuitry can be used to provide temperature stability without requiring the large voltage drop or relatively high-dissipated power needed with a bias stabilized resistor. The bandpass filter was used to reduce a spurious level. As a result, the characteristics of the receiver implemented here show more than 55 dB in gain, 50.83 dBc in a spurious level and less than 1.8 : 1 in input and output voltage standing wave ratio(VSWR), especially the carrier to noise ratio is a 43.15 dB/Hz at a 1 KHz from 1537.5 MHz.

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